FN Thomson Reuters Web of Science™ VR 1.0 PT J AU Schlichthorl, G Park, NG Frank, AJ AF Schlichthorl, G Park, NG Frank, AJ TI Estimation of the charge-collection efficiency of dye-sensitized nanocrystalline TiO2 solar cells SO ZEITSCHRIFT FUR PHYSIKALISCHE CHEMIE-INTERNATIONAL JOURNAL OF RESEARCH IN PHYSICAL CHEMISTRY & CHEMICAL PHYSICS LA English DT Article; Proceedings Paper CT 12th International Conference on Photochemical Conversion and Storage of Solar Energy CY AUG 09-14, 1998 CL BERLIN, GERMANY DE computer simulations; diffusion; charge transfer; transport properties ID MODULATED PHOTOCURRENT SPECTROSCOPY; ELECTRONIC TRANSPORT AB The dependence of the charge collection efficiency on the time constant for recombination tau(oc) and for the combined process of recombination and charge collection tau(sc) is calculated. The respective time constants can be obtained experimentally by intensity modulated photovoltage spectroscopy (IMVS) and intensity modulated photocurrent spectroscopy (IMPS) measurements. A new method is presented to determine tau(oc) and tau(sc) from the steady-state electron-concentration profiles in the TiO2 film n(x) calculated for constant light intensity. The continuity equation is modified to account for charge trapping and detrapping and the nonlinearity of the recombination rate on n. A simple expression is derived for calculating the charge-collection efficiency from the measured values of tau(oc)/tau(sc) and the light intensity dependence of tau(oc). C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Schlichthorl, G (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. RI Park, Nam-Gyu/F-2477-2014 NR 9 TC 14 Z9 14 U1 0 U2 7 PU R OLDENBOURG VERLAG PI MUNICH PA LEKTORAT M/N, K BERBER-NERLINGER, POSTFACH 80 13 60, D-81613 MUNICH, GERMANY SN 0942-9352 J9 Z PHYS CHEM JI Z. Phys. Chemie-Int. J. Res. Phys. Chem. Chem. Phys. PY 1999 VL 212 BP 45 EP 50 PN 1 PG 6 WC Chemistry, Physical SC Chemistry GA 238RP UT WOS:000082724700006 ER PT J AU Lu, HP Xie, XS AF Lu, HP Xie, XS TI Single-molecule spectroscopy studies of molecular dynamics in chemical and biological systems SO ZEITSCHRIFT FUR PHYSIKALISCHE CHEMIE-INTERNATIONAL JOURNAL OF RESEARCH IN PHYSICAL CHEMISTRY & CHEMICAL PHYSICS LA English DT Article; Proceedings Paper CT 12th International Conference on Photochemical Conversion and Storage of Solar Energy CY AUG 09-14, 1998 CL BERLIN, GERMANY DE single molecule; enzyme electron transfer; fluctuation; semiconductor ID ELECTRON-TRANSFER; ROOM-TEMPERATURE; INDIVIDUAL MOLECULES; MICROSCOPY; INTERFACE; ENERGY; ENZYME; SCALE; FILMS AB Single-molecule chemical kinetics of interfacial electron transfer from excited cresyl violet molecules to the conduction band or energetically accessible surface electronic states of indium-tin-oxide (ITO) was studied under ambient conditions. We revealed that the physical origin of multiexponential kinetics of electron transfer in this system is the inhomogeneity of molecular interactions on the semiconductor surface of ITO. Spontaneous and photo-induced spectral fluctuations of single sulforhodamine 101 molecules at the glass-polymer interface were investigated and attributed to transitions between metastable minima in the molecular potential-energy surface. Similar conformational fluctuations are also observed for the active site of the cholesterol oxidase, flavin adenine dinucleotide (FAD), which results in dynamic disorder in the enzymatic reaction of cholesterol oxidase. C1 Pacific NW Natl Lab, William R Wiley Environm Mol Sci Lab, Richland, WA 99352 USA. RP Xie, XS (reprint author), Pacific NW Natl Lab, William R Wiley Environm Mol Sci Lab, POB 999, Richland, WA 99352 USA. NR 42 TC 5 Z9 5 U1 1 U2 3 PU R OLDENBOURG VERLAG PI MUNICH PA LEKTORAT M/N, K BERBER-NERLINGER, POSTFACH 80 13 60, D-81613 MUNICH, GERMANY SN 0942-9352 J9 Z PHYS CHEM JI Z. Phys. Chemie-Int. J. Res. Phys. Chem. Chem. Phys. PY 1999 VL 212 BP 59 EP 66 PN 1 PG 8 WC Chemistry, Physical SC Chemistry GA 238RP UT WOS:000082724700008 ER PT J AU Ellingson, RJ Asbury, JB Ferrere, S Ghosh, HN Sprague, JR Lian, T Nozik, AJ AF Ellingson, RJ Asbury, JB Ferrere, S Ghosh, HN Sprague, JR Lian, T Nozik, AJ TI Sub-picosecond injection of electrons from excited [Ru(2,2 '-bipy-4,4 '-dicarboxy)(2)(SCN)(2)] into TiO2 using transient mid-infrared spectroscopy SO ZEITSCHRIFT FUR PHYSIKALISCHE CHEMIE-INTERNATIONAL JOURNAL OF RESEARCH IN PHYSICAL CHEMISTRY & CHEMICAL PHYSICS LA English DT Article; Proceedings Paper CT 12th International Conference on Photochemical Conversion and Storage of Solar Energy CY AUG 09-14, 1998 CL BERLIN, GERMANY DE dynamics of dye injection; N3; nanocrystalline TiO2; dye sensitization; monocrystalline TiO2; fast laser spectroscopy; ultrafast electron injection ID TITANIUM-DIOXIDE FILMS; RU-DYE MOLECULES; STATES AB We have used femtosecond pump-probe spectroscopy to time resolve the injection of electrons into nanocrystalline TiO2 film electrodes under ambient conditions following photoexcitation of the adsorbed dye, [Ru(4,4'-dicarboxy-2,2'-bipyridine)(2)(NCS)(2)] (N3). Pumping at one of the metal-to-ligand charge transfer absorption peaks and probing the absorption of electrons injected into the TiO2, conduction band at 1.52 mu m and in the range of 4.1 to 7.0 mu m, we have directly observed the arrival of the injected electrons. Our measurements indicate an instrument-limited similar to 50-fs upper limit on the electron injection time under ambient conditions in air. We have compared the infrared transient absorption for noninjecting (blank) systems consisting of N3 in ethanol and N3 adsorbed to films of nanocrystalline Al2O3 and ZrO2, and found no indication of electron injection at probe wavelengths in the mid-IR (4.1 to 7.0 mu m). At 1.52 mu m interferences exist in the observed transient absorption signal for the blanks. C1 Natl Renewable Energy Lab, Ctr Basic Sci, Golden, CO 80401 USA. Emory Univ, Dept Chem, Atlanta, GA 30322 USA. RP Nozik, AJ (reprint author), Natl Renewable Energy Lab, Ctr Basic Sci, Golden, CO 80401 USA. RI Ellingson, Randy/H-3424-2013; Lian, Tianquan/L-8992-2013; Ghosh, Hirendra/J-8776-2012; Nozik, Arthur/A-1481-2012; Nozik, Arthur/P-2641-2016 OI Lian, Tianquan/0000-0002-8351-3690; NR 18 TC 26 Z9 26 U1 0 U2 13 PU R OLDENBOURG VERLAG PI MUNICH PA LEKTORAT M/N, K BERBER-NERLINGER, POSTFACH 80 13 60, D-81613 MUNICH, GERMANY SN 0942-9352 J9 Z PHYS CHEM JI Z. Phys. Chemie-Int. J. Res. Phys. Chem. Chem. Phys. PY 1999 VL 212 BP 77 EP 84 PN 1 PG 8 WC Chemistry, Physical SC Chemistry GA 238RP UT WOS:000082724700010 ER PT J AU Takahashi, S Suzuya, K Kohara, S Koura, N Curtiss, LA Saboungi, ML AF Takahashi, S Suzuya, K Kohara, S Koura, N Curtiss, LA Saboungi, ML TI Structure of 1-ethyl-3-methylimidazolium chloroaluminates: Neutron diffraction measurements and ab initio calculations SO ZEITSCHRIFT FUR PHYSIKALISCHE CHEMIE-INTERNATIONAL JOURNAL OF RESEARCH IN PHYSICAL CHEMISTRY & CHEMICAL PHYSICS LA English DT Article DE room temperature molten salt; chloroaluminates structure; neutron diffraction; ab initio calculations ID TEMPERATURE MOLTEN-SALT; IONIC LIQUIDS; ALUMINUM; ELECTROCHEMISTRY; SPECTROSCOPY; CHLORIDE; MELTS AB The structures of AlCl3-1-ethyl-3-methyl-imidazolium chloride melts in the concentration range of 46-67 mol% AlCl3 were measured by neutron diffraction techniques. Ab initio molecular orbital calculations (6-31G* basis set) were carried out on the isolated ions which are known to form in these melts (AlCl4-, Al2Cl7-, and EMI+) and some of their complexes (AlCl4-... EMI+ and Al2Cl7-... EMI+). The structures and binding energies of AlCl4-... EMI+ and Al2Cl7-... EMI+ are presented. The diffraction patterns derived from the complexes and the isolated ions are compared with the measurements. C1 Argonne Natl Lab, Argonne, IL 60439 USA. RP Takahashi, S (reprint author), Nisshin Steel Co Ltd, Steel & Technol Dev Lab, 7-1 Koya Shinmachi, Chiba 272, Japan. RI Saboungi, Marie-Louise/C-5920-2013 OI Saboungi, Marie-Louise/0000-0002-0607-4815 NR 19 TC 66 Z9 68 U1 3 U2 19 PU R OLDENBOURG VERLAG PI MUNICH PA LEKTORAT M/N, K BERBER-NERLINGER, POSTFACH 80 13 60, D-81613 MUNICH, GERMANY SN 0942-9352 J9 Z PHYS CHEM JI Z. Phys. Chemie-Int. J. Res. Phys. Chem. Chem. Phys. PY 1999 VL 209 BP 209 EP 221 PN 2 PG 13 WC Chemistry, Physical SC Chemistry GA 182HT UT WOS:000079493700004 ER PT J AU Deevi, SC Morris, DG Sikka, VK Schneibel, JH AF Deevi, SC Morris, DG Sikka, VK Schneibel, JH TI Iron aluminides: Alloy design, processing, properties and applications - Preface SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Editorial Material C1 Philip Morris USA, Richmond, VA USA. Univ Neuchatel, CH-2000 Neuchatel, Switzerland. Oak Ridge Natl Lab, Oak Ridge, TN USA. RP Deevi, SC (reprint author), Philip Morris USA, Richmond, VA USA. RI Morris, David/B-2742-2014 NR 0 TC 4 Z9 4 U1 1 U2 3 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0921-5093 J9 MAT SCI ENG A-STRUCT JI Mater. Sci. Eng. A-Struct. Mater. Prop. Microstruct. Process. PD DEC 31 PY 1998 VL 258 IS 1-2 BP XI EP XI PG 1 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 153XA UT WOS:000077857500001 ER PT J AU Savage, MF Srinivasan, R Daw, MS Lograsso, T Mills, MJ AF Savage, MF Srinivasan, R Daw, MS Lograsso, T Mills, MJ TI Dislocation processes and deformation behavior in (Fe,Ni)-Al single crystals SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article; Proceedings Paper CT International Symposium on Iron Aluminides - Alloy Design, Processing, Properties and Applications CY FEB 15-19, 1998 CL SAN ANTONIO, TEXAS SP Mat Sci Crit Technol Sector, Intermetall Mat Comm, ASM Int, Flow & Fracture Comm, TMS DE (Fe,Ni)-Al; dislocation microstructure; single crystals; APB tubes ID DOMAIN BOUNDARY TUBES; ORDERED ALLOYS; FEAL; ADDITIONS; SLIP AB The mechanical properties and the dislocation microstructure of single crystals with a range of compositions within the (Fe,Ni)-Al pseudobinary system have been investigated, with the purpose of bridging the behavior from FeAl to NiAl. Initial experiments are focused on compression testing of [001] oriented single crystals with a family of compositions of the form Fe-x-Ni60-x-Al-40 (where x = 60, 50 and 10 at.%). Measurements of yield strength and work hardening rates have been correlated with overall dislocation morphology, dislocation dissociation width and the presence of APE tubes. (C) 1998 Published by Elsevier Science S.A. All rights reserved. C1 Ohio State Univ, Dept Mat Sci & Engn, Columbus, OH 43210 USA. Clemson Univ, Dept Phys & Astron, Clemson, SC 29634 USA. Ames Lab, Ames, IA 50011 USA. RP Savage, MF (reprint author), Ohio State Univ, Dept Mat Sci & Engn, 116 W 19Th Ave, Columbus, OH 43210 USA. NR 18 TC 14 Z9 15 U1 0 U2 3 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0921-5093 J9 MAT SCI ENG A-STRUCT JI Mater. Sci. Eng. A-Struct. Mater. Prop. Microstruct. Process. PD DEC 31 PY 1998 VL 258 IS 1-2 BP 20 EP 25 DI 10.1016/S0921-5093(98)00911-3 PG 6 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 153XA UT WOS:000077857500004 ER PT J AU Hartig, C Yoo, MH Koeppe, Y Mecking, H AF Hartig, C Yoo, MH Koeppe, Y Mecking, H TI Effect of temperature on elastic constants and deformation behavior in shear tests of Fe-30%Al single crystals SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article; Proceedings Paper CT International Symposium on Iron Aluminides - Alloy Design, Processing, Properties and Applications CY FEB 15-19, 1998 CL SAN ANTONIO, TX SP Mat Sci Crit Technol Sector, Intermetall Mat Comm, ASM Int, Flow & Fracture Comm, TMS ID FE3AL; SUPERDISLOCATIONS; FLOW; FEAL AB Simple shear tests of Fe-30% Al single crystals were performed in order to measure the critical resolved shear stresses (CRSS's) for {110}[111] slip and {112}[111] slip independently and without superimposed normal stresses on the slip planes. The temperature dependence of the CRSS's for slip on {110} was found to be similar to that of the CRSS's observed in compression. For a detailed study of dislocation micromechanics to explain the plastic deformation behavior of Fe-30% Al, discussion is given on the anisotropy of APE energies and that of the elastic compliance constants referred to the respective slip planes. (C) 1998 Elsevier Science S.A. All rights reserved. C1 Tech Univ Hamburg, D-21071 Hamburg, Germany. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Hartig, C (reprint author), Tech Univ Hamburg, D-21071 Hamburg, Germany. RI Hartig, Christian/F-4673-2010 NR 20 TC 9 Z9 9 U1 1 U2 5 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0921-5093 J9 MAT SCI ENG A-STRUCT JI Mater. Sci. Eng. A-Struct. Mater. Prop. Microstruct. Process. PD DEC 31 PY 1998 VL 258 IS 1-2 BP 59 EP 64 DI 10.1016/S0921-5093(98)00917-4 PG 6 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 153XA UT WOS:000077857500010 ER PT J AU Yoshimi, K Saeki, Y Yoo, MH Hanada, S AF Yoshimi, K Saeki, Y Yoo, MH Hanada, S TI Room temperature tensile properties of Fe-Al single crystals strengthened by excess vacancies SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article; Proceedings Paper CT International Symposium on Iron Aluminides - Alloy Design, Processing, Properties and Applications CY FEB 15-19, 1998 CL SAN ANTONIO, TEXAS SP Mat Sci Crit Technol Sector, Intermetall Mat Comm, ASM Int, Flow & Fracture Comm, TMS ID DEFECT CONCENTRATIONS; COOLING RATE; B2 STRUCTURE; B2-TYPE; INTERMETALLICS; STOICHIOMETRY; ALUMINIDES; BEHAVIOR; HARDNESS AB Effects of supersaturated excess vacancies on plastic deformation of Fe-Al were investigated by tensile testing at room temperature for three different single crystals (Fe-33, 41 and 44 mol% Al). Critical resolved shear stresses (CRSSs) of slowly-cooled specimens (as homogenized specimens) and well-annealed specimens (vacancy-eliminated specimens) were almost the same and did not show Al concentration dependence. On the other hand, the CRSS of vacancy-containing specimens (fast-cooled specimens) was significantly higher than that of the others, even for Fe-33 mol% Al, and showed strong Al concentration dependence. The fast-cooled specimens displayed serrated flow behavior during work-hardening at room temperature, and the serrated flow was more intensive at a higher Al composition. Deformation microstructures of Fe-44 mol% Al were examined by TEM, and it was found that dislocations in fast-cooled specimens were inhomogeneously distributed, suggesting jerky motion of slip dislocations. These dislocations were oriented along an unstable direction estimated from dislocation line tension. In addition, there were numerous dislocation loops. A dislocation mechanism of the excess vacancy strengthening is discussed on the basis of the experimental results. (C) 1998 Elsevier Science S.A. All rights reserved. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. Tohoku Univ, Inst Mat Res, Sendai, Miyagi 98077, Japan. Tohoku Univ, Dept Mat Proc, Sendai, Miyagi 98077, Japan. RP Yoshimi, K (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. NR 26 TC 9 Z9 9 U1 0 U2 5 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0921-5093 J9 MAT SCI ENG A-STRUCT JI Mater. Sci. Eng. A-Struct. Mater. Prop. Microstruct. Process. PD DEC 31 PY 1998 VL 258 IS 1-2 BP 75 EP 83 DI 10.1016/S0921-5093(98)00920-4 PG 9 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 153XA UT WOS:000077857500013 ER PT J AU Liu, CT George, EP Maziasz, PJ Schneibel, JH AF Liu, CT George, EP Maziasz, PJ Schneibel, JH TI Recent advances in B2 iron aluminide alloys: deformation, fracture and alloy design SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article; Proceedings Paper CT International Symposium on Iron Aluminides - Alloy Design, Processing, Properties and Applications CY FEB 15-19, 1998 CL SAN ANTONIO, TX SP Mat Sci Crit Technol Sector, Intermetall Mat Comm, ASM Int, Flow & Fracture Comm, TMS DE FeAl alloys; tensile ductility; deformation; fracture; thermal vacancies ID ROOM-TEMPERATURE DUCTILITY; ENVIRONMENTAL EMBRITTLEMENT; HYDROGEN EMBRITTLEMENT; MECHANICAL-PROPERTIES; INTERMETALLIC PHASES; SINGLE-CRYSTALS; WATER-VAPOR; FEAL ALLOYS; STRAIN-RATE; DOPED FEAL AB This paper reviews the deformation, fracture and alloy design of B2 iron aluminides based on FeAl. Moisture-induced environmental embrittlement is shown to be a leading cause of low tensile ductility and brittle cleavage fracture of Fe-rich FeAl alloys at ambient temperatures. With increasing Al concentration, two other factors, namely intrinsic grain-boundary weakness and quenched-in vacancies become important in limiting the tensile ductility of FeAl alloys. FeAl alloys show a yield-strength anomaly at intermediate temperatures. Recent work indicates that the anomaly is a result of hardening by thermal vacancies at elevated temperatures. The understanding of the deformation and fracture behavior has led to the development of FeAl-base alloys and composites with improved metallurgical and mechanical properties for structural applications. These FeAl-based alloys can be prepared by melting and casting or by powder processing. The unique combination of the excellent oxidation and carburization/sulfidation resistance coupled with relatively low material density and good mechanical properties at room and elevated temperatures has sparked industrial interest in FeAl alloys and composites for a number of applications. (C) 1998 Elsevier Science S.A. All rights reserved. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Liu, CT (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, POB 2008, Oak Ridge, TN 37831 USA. RI George, Easo/L-5434-2014; OI Maziasz, Philip/0000-0001-8207-334X; Liu, Chain Tsuan/0000-0001-7888-9725 NR 90 TC 200 Z9 213 U1 5 U2 44 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0921-5093 EI 1873-4936 J9 MAT SCI ENG A-STRUCT JI Mater. Sci. Eng. A-Struct. Mater. Prop. Microstruct. Process. PD DEC 31 PY 1998 VL 258 IS 1-2 BP 84 EP 98 DI 10.1016/S0921-5093(98)00921-6 PG 15 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 153XA UT WOS:000077857500014 ER PT J AU Tortorelli, PF Natesan, K AF Tortorelli, PF Natesan, K TI Critical factors affecting the high-temperature corrosion performance of iron aluminides SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article; Proceedings Paper CT International Symposium on Iron Aluminides - Alloy Design, Processing, Properties and Applications CY FEB 15-19, 1998 CL SAN ANTONIO, TX SP Mat Sci Crit Technol Sector, Intermetall Mat Comm, ASM Int, Flow & Fracture Comm, TMS DE high-temperature corrosion; iron aluminides; oxidation; sulfidation; alumina scales; scale adhesion; oxidation lifetimes ID FE-AL ALLOYS; REACTIVE ELEMENTS; SULFIDATION PROPERTIES; OXIDATION RESISTANCE; BEHAVIOR; SULFUR; METAL; SPALLATION; GROWTH; DISPERSIONS AB Iron aluminides are known to exhibit good-to-excellent corrosion resistance in a number of high-temperature environments. Under most conditions, this resistance derives from the establishment and maintenance of a sound and adherent alumina layer. Consequently the performance of iron aluminides under different aggressive high-temperature can be related to fundamental factors that affect the development, adhesion, and durability (lifetime) of protective alumina. Overall corrosion resistance depends not only on thermodynamic stability of the reaction product in a particular environment and its growth kinetics, hut also on scale integrity and morphology, the chemical and physical nature of the oxide-metal interface, alloy strength, and the specific composition of the iron aluminide. Despite the multiplicity of factors, a relatively simple lifetime prediction model based on aluminum consumption can be used to evaluate the influences of changes in material parameters and to determine approaches to improving high-temperature corrosion resistance of iron aluminides. (C) 1998 Published by Elsevier Science S.A. All rights reserved. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Argonne Natl Lab, Argonne, IL 60439 USA. RP Tortorelli, PF (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. RI Tortorelli, Peter/E-2433-2011 NR 90 TC 167 Z9 171 U1 1 U2 13 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0921-5093 J9 MAT SCI ENG A-STRUCT JI Mater. Sci. Eng. A-Struct. Mater. Prop. Microstruct. Process. PD DEC 31 PY 1998 VL 258 IS 1-2 BP 115 EP 125 DI 10.1016/S0921-5093(98)00924-1 PG 11 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 153XA UT WOS:000077857500017 ER PT J AU Natesan, K AF Natesan, K TI Corrosion performance of iron aluminides in mixed-oxidant environments SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article; Proceedings Paper CT International Symposium on Iron Aluminides - Alloy Design, Processing, Properties and Applications CY FEB 15-19, 1998 CL SAN ANTONIO, TEXAS SP Mat Sci Crit Technol Sector, Intermetall Mat Comm, ASM Int, Flow & Fracture Comm, TMS DE corrosion; iron aluminides; mixed-oxidant; electrospark deposition; gasification; combustion ID FE-AL ALLOYS; OXIDATION; BEHAVIOR AB Iron aluminide intermetallics are being developed for use as structural materials and/or as cladding for conventional engineering alloys. In addition to their strength advantages, these materials exhibit excellent resistance to corrosion in single- and multi-oxidant environments at elevated temperatures through the formation of slow-growing, adherent alumina scales. Even though these intermetallics develop protective oxide scales in single-oxidant environments, the simultaneous presence of several reactants in the environment (typical of practical systems) can lead to development of oxide scales that are non-protective and undergo breakaway corrosion or to non-oxide scales that are detrimental to the performance of underlying ahoy. This paper describes the corrosion performance of Fe-Al intermetallics in environments that contain sulfur, carbon, chlorine, and oxygen and that are typical of industrial applications and power generation systems. Emphasis is on mechanisms of scale development/breakdown, performance envelopes for long-term usage of these materials, approaches to modifying the surfaces of engineering alloys by cladding or coating them with intermetallics, and corrosion experience in practical environments. (C) 1998 Published by Elsevier Science S.A. All rights reserved. C1 Argonne Natl Lab, Div Energy Technol, Argonne, IL 60439 USA. RP Natesan, K (reprint author), Argonne Natl Lab, Div Energy Technol, 9700 S Cass Ave,Bldg 212, Argonne, IL 60439 USA. NR 20 TC 74 Z9 74 U1 1 U2 9 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0921-5093 J9 MAT SCI ENG A-STRUCT JI Mater. Sci. Eng. A-Struct. Mater. Prop. Microstruct. Process. PD DEC 31 PY 1998 VL 258 IS 1-2 BP 126 EP 134 DI 10.1016/S0921-5093(98)00925-3 PG 9 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 153XA UT WOS:000077857500018 ER PT J AU Hosoda, H Yoshimi, K Inoue, K Hanada, S AF Hosoda, H Yoshimi, K Inoue, K Hanada, S TI Effect of wet environment on hardness and yield stress of B2 Fe-Al alloys SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article; Proceedings Paper CT International Symposium on Iron Aluminides - Alloy Design, Processing, Properties and Applications CY FEB 15-19, 1998 CL SAN ANTONIO, TEXAS SP Mat Sci Crit Technol Sector, Intermetall Mat Comm, ASM Int, Flow & Fracture Comm, TMS ID EMBRITTLEMENT; HYDROGEN; METALS AB Effects of wet environment on hardness and yield stress of B2 Fe-Al alloys at room temperature (RT) were investigated. First, change in micro Vickers hardness was measured for annealed Fe-18 mol% Al and Fe-25 mol% Al alloys as a function of the duration spent in: (1) distilled water at RT after a drying treatment; and (2) dry air at 427 K after a wet treatment. An age-hardening-like phenomenon appears for the former case and an age-softening-like phenomenon takes place for the latter case. Such changes in hardness caused by environmental treatments are reversible. Second, room-temperature yield stress and hardness were measured for annealed and vacancy-introduced Fe-44 mol% Al single-crystal alloys, where specimens were kept in various environments for a long time in order to achieve their equilibrium states. It is concluded that, with absorbing hydrogen, annealed Fe-Al alloys are hardened and vacancy-introduced Fe-AL alloys are softened. A new method is proposed for estimating the diffusivity of a solute. Hydrogen diffusivity (D-H) at RT is estimated to be around 10(-11) m(2)/s for Fe18Al and 10(-12) m(2)/s for Fe25Al, suggesting that D-H is lowered with increasing Al content in Fe-Al alloys. (C) 1998 Elsevier Science S.A. All rights reserved. C1 Tohoku Univ, Inst Mat Res, Aoba Ku, Sendai, Miyagi 9808577, Japan. Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. Univ Washington, Dept Mat Sci & Engn, Seattle, WA 98195 USA. RP Hosoda, H (reprint author), Tohoku Univ, Inst Mat Res, Aoba Ku, 2-1-1 Katahira, Sendai, Miyagi 9808577, Japan. EM hhosoda@imr.tohoku.ac.jp NR 23 TC 8 Z9 11 U1 0 U2 2 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0921-5093 J9 MAT SCI ENG A-STRUCT JI Mater. Sci. Eng. A-Struct. Mater. Prop. Microstruct. Process. PD DEC 31 PY 1998 VL 258 IS 1-2 BP 135 EP 145 DI 10.1016/S0921-5093(98)00926-5 PG 11 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 153XA UT WOS:000077857500019 ER PT J AU Schneibel, JH AF Schneibel, JH TI Strengthening of iron aluminides by vacancies and/or nickel SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article; Proceedings Paper CT International Symposium on Iron Aluminides - Alloy Design, Processing, Properties and Applications CY FEB 15-19, 1998 CL SAN ANTONIO, TX SP Mat Sci Crit Technol Sector, Intermetall Mat Comm, ASM Int, Flow & Fracture Comm, TMS DE iron aluminides; solid solution strengthening; thermal vacancies; vacancy migration ID TERNARY ADDITIONS; FEAL; HARDNESS; DEFECTS AB At room temperature, iron aluminides may be strengthened by quenched-in thermal vacancies as well as by solid solution alloying additions. Since the separation of these two effects requires precise vacancy concentration measurements, a novel extrapolation procedure was developed to determine vacancy volume fractions with an accuracy approaching 1 part in 10 000. The rate of removal of quenched-in vacancies during annealing, as well as the hardening by vacancies, were found to be influenced by solid solution additions of Ni to Fe-45 at.% Al. First, yield strength and density measurements showed that nickel slows down the removal of vacancies, making it more difficult to obtain iron aluminides with low vacancy concentrations. Second, in the absence of vacancies, additions of nickel result in substantial strengthening. Third, for high vacancy concentrations (e.g. 0.2 vol.%), nickel additions can cause softening. These results are rationalized in terms of the interaction between the vacancies and the nickel atoms. (C) 1998 Elsevier Science S.A. All rights reserved. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Schneibel, JH (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, POB 2008, Oak Ridge, TN 37831 USA. EM schneibeljh@ornl.gov NR 15 TC 18 Z9 18 U1 0 U2 2 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0921-5093 EI 1873-4936 J9 MAT SCI ENG A-STRUCT JI Mater. Sci. Eng. A-Struct. Mater. Prop. Microstruct. Process. PD DEC 31 PY 1998 VL 258 IS 1-2 BP 181 EP 186 DI 10.1016/S0921-5093(98)00932-0 PG 6 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 153XA UT WOS:000077857500025 ER PT J AU Deevi, SC Swindeman, RW AF Deevi, SC Swindeman, RW TI Yielding, hardening and creep behavior of iron aluminides SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article; Proceedings Paper CT International Symposium on Iron Aluminides - Alloy Design, Processing, Properties and Applications CY FEB 15-19, 1998 CL SAN ANTONIO, TEXAS SP Mat Sci Crit Technol Sector, Intermetall Mat Comm, ASM Int, Flow & Fracture Comm, TMS DE iron aluminides; tensile properties; cyclic deformation; creep properties; modules; structural analysis AB Engineering properties of powder processed iron aluminides (Fe-24 wt.% Al alloy) obtained by hot extrusion and roll compaction of water atomized powder were investigated to assist in the structural analysis of FeAl components exposed to short-time, thermal-mechanical loadings. The test matrix for high-temperature deformation of FeAl incorporated powder processed sheet and bar product forms. Tensile, cyclic, creep and relaxation tests were carried out from room temperature to 750 degrees C on the bar products. Sheets were characterized for their tensile and creep properties. The experimental data were sufficient to provide rules for yielding, hardening and creep in the temperatures range of 23-750 degrees C. The room temperature curve adjusted for the temperature dependence of the modulus may be used for the yield and hardening behavior between 23 and 600 degrees C. Above 600 degrees C, the yield can be obtained from the tensile curve for the temperature of interest. Exposure to 750 degrees C causes sufficient recovery and resets the kinematic and isotropic hardening parameters to their initial values. Variation of Young's modulus with increase of temperature is also presented. Limited creep behavior is also discussed. Structural analysis of the FeAl components can be carried out using finite element modeling techniques with the availability of the tensile, cyclic, relaxation and creep behavior of FeAl at elevated temperatures. (C) 1998 Published by Elsevier Science S.A. All rights reserved. C1 Philip Morris USA, Res Dev & Engn Ctr, Richmond, VA 23234 USA. Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN USA. RP Deevi, SC (reprint author), Philip Morris USA, Res Dev & Engn Ctr, Richmond, VA 23234 USA. NR 19 TC 23 Z9 23 U1 1 U2 5 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0921-5093 J9 MAT SCI ENG A-STRUCT JI Mater. Sci. Eng. A-Struct. Mater. Prop. Microstruct. Process. PD DEC 31 PY 1998 VL 258 IS 1-2 BP 203 EP 210 DI 10.1016/S0921-5093(98)00935-6 PG 8 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 153XA UT WOS:000077857500028 ER PT J AU Sikka, VK Wilkening, D Liebetrau, J Mackey, B AF Sikka, VK Wilkening, D Liebetrau, J Mackey, B TI Melting and casting of FeAl-based cast alloy SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article; Proceedings Paper CT International Symposium on Iron Aluminides - Alloy Design, Processing, Properties and Applications CY FEB 15-19, 1998 CL SAN ANTONIO, TEXAS SP Mat Sci Crit Technol Sector, Intermetall Mat Comm, ASM Int, Flow & Fracture Comm, TMS DE iron aluminide; FeAl; Exo-Melt (TM); melting; casting; aluminide ID IRON ALUMINIDES; EMBRITTLEMENT AB The FeAl-based intermetallic alloys are of great interest because of their low density, low raw material cost, and excellent resistance to high-temperature oxidation, sulfidation, carburization, and molten salts. The applications based on these unique properties of FeAl require methods to melt and cast these alloys into complex-shaped castings and centrifugal cast tubes. This paper addresses the melting-related issues and the effect of chemistry on the microstructure and hardness of castings. It is concluded that the use of the Exo-Melt(TM) process for melting and the proper selection of the aluminum melt stock can result in porosity-free castings. The FeAl alloys can be melted and cast from the virgin and revert stock. A large variation in carbon content of the alloys is possible before the precipitation of graphite flakes occurs. Titanium is a very potent addition to refine the grain size of castings. A range of complex sand castings and two different sizes of centrifugal cast tubes of the alloy have already been cast. (C) 1998 Elsevier Science S.A. All rights reserved. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. Columbia Falls Aluminum Co, Columbia Falls, MT 59912 USA. AFFCO LLC, Anaconda, MT 59711 USA. RP Sikka, VK (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, POB 2008, Oak Ridge, TN 37831 USA. NR 18 TC 40 Z9 47 U1 3 U2 5 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0921-5093 J9 MAT SCI ENG A-STRUCT JI Mater. Sci. Eng. A-Struct. Mater. Prop. Microstruct. Process. PD DEC 31 PY 1998 VL 258 IS 1-2 BP 229 EP 235 DI 10.1016/S0921-5093(98)00938-1 PG 7 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 153XA UT WOS:000077857500031 ER PT J AU Hajaligol, MR Deevi, SC Sikka, VK Scorey, CR AF Hajaligol, MR Deevi, SC Sikka, VK Scorey, CR TI A thermomechanical process to make iron aluminide (FeAl) sheet SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article; Proceedings Paper CT International Symposium on Iron Aluminides - Alloy Design, Processing, Properties and Applications CY FEB 15-19, 1998 CL SAN ANTONIO, TEXAS SP Mat Sci Crit Technol Sector, Intermetall Mat Comm, ASM Int, Flow & Fracture Comm, TMS DE iron aluminide; intermetallics; roll-compaction; powder forming; cold-rolling; sintering AB An innovative combination of roll compaction, and thermomechanical processing allowed manufacture of FeAl alloy intermetallic sheets with 24 wt.% Al content. Green sheets of FeAl were obtained by roll compaction of water atomized FeAl powder with a polymeric binder. Roll compacted green sheets were de-bindered and partially sintered prior to cold rolling through tungsten carbide rolls. Cold rolling decreased the thickness, reduced the level of porosity and work-hardened the sheets. Several intermediate annealings at or above 1100 degrees C were found to be necessary to relieve the work hardening stresses prior to rolling the sheets to a final thickness of 0.20 mm. The annealing temperatures were chosen to be at or above 1100 degrees C to allow concurrent sintering of FeAl necessary for the densification of FeAl sheets. Thermomechanical processing of cold rolled sheets allowed commercial manufacture of FeAl intermetallic sheets without the necessity of hot rolling of a cast FeAl ingot. Fully dense sheets possess fine grain microstructure with an average grain size of 20 mu m. The electrical resistivities of FeAl sheets can be varied from 140 to 155 mu Omega cm(-1), and the high resistivities make them ideally suited for resistive heating applications. Mechanical propel-ties of FeAl sheets are comparable to the properties of hot extruded FeAl alloys. (C) 1998 Elsevier Science S.A. All rights resented. C1 Philip Morris Inc, Ctr Res & Dev, Richmond, VA 23261 USA. Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37387 USA. Ametek Specialty Met Div, Wallingford, CT 06492 USA. RP Hajaligol, MR (reprint author), Philip Morris Inc, Ctr Res & Dev, 4201 Commerce Rd,POB 26581, Richmond, VA 23261 USA. NR 24 TC 45 Z9 45 U1 0 U2 3 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0921-5093 J9 MAT SCI ENG A-STRUCT JI Mater. Sci. Eng. A-Struct. Mater. Prop. Microstruct. Process. PD DEC 31 PY 1998 VL 258 IS 1-2 BP 249 EP 257 DI 10.1016/S0921-5093(98)00941-1 PG 9 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 153XA UT WOS:000077857500034 ER PT J AU Mistler, RE Sikka, VK Scorey, CR McKernan, JE Hajaligol, MR AF Mistler, RE Sikka, VK Scorey, CR McKernan, JE Hajaligol, MR TI Tape casting as a fabrication process for iron aluminide (FeAl) thin sheets SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article; Proceedings Paper CT International Symposium on Iron Aluminides - Alloy Design, Processing, Properties and Applications CY FEB 15-19, 1998 CL SAN ANTONIO, TEXAS SP Mat Sci Crit Technol Sector, Intermetall Mat Comm, ASM Int, Flow & Fracture Comm, TMS DE type casting; iron aluminide; sheet; manufacturing process AB The conversion of iron aluminide powder into a slurry followed by tape casting into a green sheet was investigated. Casting parameters affecting green sheet properties were studied. Application of thermo-mechanical processing including sintering, cold rolling, annealing and heat treating resulted in sheets with a fine-grain structure at essentially 100% of theoretical density. The various microstructures developed throughout the process are described, along with tensile property measurements on the fully dense product. Differences in property with sheets made by other processes are explained, and it is demonstrated that tape casting is a viable method of making thin gauge sheets of iron aluminide with a wide range of compositions. (C) 1998 Elsevier Science S.A. All rights reserved. C1 Philip Morris Inc, Ctr Res & Dev, Richmond, VA 23261 USA. Richard E Mistler Inc, Morrisville, PA 19067 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Ametek Inc, Wallingford, CT 06492 USA. RP Hajaligol, MR (reprint author), Philip Morris Inc, Ctr Res & Dev, POB 26583, Richmond, VA 23261 USA. NR 9 TC 15 Z9 15 U1 1 U2 5 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0921-5093 J9 MAT SCI ENG A-STRUCT JI Mater. Sci. Eng. A-Struct. Mater. Prop. Microstruct. Process. PD DEC 31 PY 1998 VL 258 IS 1-2 BP 258 EP 265 DI 10.1016/S0921-5093(98)00942-3 PG 8 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 153XA UT WOS:000077857500035 ER PT J AU Santella, ML Patterson, AB AF Santella, ML Patterson, AB TI Wetting of iron aluminide alloys by Ag, Au, and Cu SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article; Proceedings Paper CT International Symposium on Iron Aluminides - Alloy Design, Processing, Properties and Applications CY FEB 15-19, 1998 CL SAN ANTONIO, TEXAS SP Mat Sci Crit Technol Sector, Intermetall Mat Comm, ASM Int, Flow & Fracture Comm, TMS DE contact angle; intermetallic alloy; surfaces; wetting; iron aluminide; FeAl; Fe3Al; iron-aluminium alloy ID WELDABILITY AB Because successful integration of alloys into engineering structures often relies on joining technologies this study was done to learn about behavior relevant to brazing of iron aluminide alloys. Brazing processes are largely controlled by the wetting phenomenon, i.e. how well a liquid spreads over the surface of a solid. These experiments involved melting pure silver, copper and gold on the surfaces of Fe0.748Al0.252 and Fe0.589Al0.411 by induction heating in a vacuum chamber. The wetting contact angles were measured as a function of time. These Fe,AI, alloys were wetted by Ag and Au (contact angles, theta < 90 degrees). The Ag and An droplets both dissolved Al from the FexAly substrates. Silver melted near its reference temperature of 960 degrees C and immediately formed a contact angle < 90 degrees, Within minutes, the Ag droplets attained contact angles near 10 degrees. Cold began melting below its reference temperature of 1063 degrees C and this was attributed to Al diffusion into the solid Au. The Au alloy droplets formed contact angles of similar to 10 degrees in < 1 min. Liquid from both Ag and Au droplets penetrated the grain boundaries of the FexAly alloys. A substantial reaction zone also formed under the Ag and Au droplets. In contrast, liquid Cu did not wet the FexAly alloys. (C) 1998 Elsevier Science S.A. Al rights reserved. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Santella, ML (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, POB 2008, Oak Ridge, TN 37831 USA. NR 12 TC 8 Z9 8 U1 1 U2 4 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0921-5093 J9 MAT SCI ENG A-STRUCT JI Mater. Sci. Eng. A-Struct. Mater. Prop. Microstruct. Process. PD DEC 31 PY 1998 VL 258 IS 1-2 BP 270 EP 275 DI 10.1016/S0921-5093(98)00944-7 PG 6 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 153XA UT WOS:000077857500037 ER PT J AU Alexander, DJ Maziasz, PJ Wright, JL AF Alexander, DJ Maziasz, PJ Wright, JL TI Processing and alloying effects on tensile and impact properties of FeAl alloys SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article; Proceedings Paper CT International Symposium on Iron Aluminides - Alloy Design, Processing, Properties and Applications CY FEB 15-19, 1998 CL SAN ANTONIO, TEXAS SP Mat Sci Crit Technol Sector, Intermetall Mat Comm, ASM Int, Flow & Fracture Comm, TMS DE iron-aluminides; B2 phase; FeAl; powder metallurgy; fine-grained microstructure; ductility; impact-toughness ID ROOM-TEMPERATURE; EMBRITTLEMENT; STRENGTH AB Two series of iron aluminide alloys [Fe-36-38Al (at.%)] were produced by ingot metallurgy or powder metallurgy methods, to examine the effects of processing and of slight changes in chemical composition on the microstructure and mechanical properties. For the first series of alloys, the powder metallurgy materials developed a very fine grain size when extruded at 950 or 1000 degrees C, much finer than the initial powder particle size. Extrusion at 1100 degrees C resulted in a coarser grain size. The fine-grained powder alloys showed excellent strength and ductility, and high levels of energy absorption in impact tests. The high levels of energy absorption were caused by extensive crack deflection along the remnant oxide layers from the prior particle boundaries; these boundaries had been elongated and oriented perpendicular to the notch by the extrusion process. The coarse-grained material, which had larger, mon isolated oxide particles, had slightly lower ductility, but had much poorer impact properties, with no crack deflection. Ingot metallurgy alloys of similar composition, extruded at 900 degrees C, had lower strength and ductility than the powder materials. The addition of boron (0.021 at.%) resulted in a change of fracture mode in the impact tests from intergranular to transgranular, which significantly increased the energy absorption. A second series of cast FeAl alloys examined the effect of changes in the levels of Zr, C, and B, as compared to the first series of alloys. Increases in the Zr and C resulted in increases in the strength and slight decreases in the ductility. Numerous flaws, apparently created during machining of the cast material, were observed on the surfaces of the impact specimens, which still showed some energy absorption when tested. Different fracture modes, including cleavage, intergranular, and ductile tearing, were observed on the fracture surfaces of various impact specimens. (C) 1998 Published by Elsevier Science S.A. All rights reserved. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Alexander, DJ (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, POB 2008, Oak Ridge, TN 37831 USA. OI Maziasz, Philip/0000-0001-8207-334X NR 10 TC 21 Z9 23 U1 1 U2 4 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0921-5093 J9 MAT SCI ENG A-STRUCT JI Mater. Sci. Eng. A-Struct. Mater. Prop. Microstruct. Process. PD DEC 31 PY 1998 VL 258 IS 1-2 BP 276 EP 284 DI 10.1016/S0921-5093(98)00945-9 PG 9 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 153XA UT WOS:000077857500038 ER PT J AU Wright, RN Anderson, MT Wright, JK AF Wright, RN Anderson, MT Wright, JK TI Microstructure and properties of an oxide dispersion-strengthened iron aluminide SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article; Proceedings Paper CT International Symposium on Iron Aluminides - Alloy Design, Processing, Properties and Applications CY FEB 15-19, 1998 CL SAN ANTONIO, TEXAS SP Mat Sci Crit Technol Sector, Intermetall Mat Comm, ASM Int, Flow & Fracture Comm, TMS DE Fe3Al; creep; oxide strengthening ID CREEP RESISTANCE; FE3AL; ALLOYS AB Oxide dispersion-strengthened (ODS) iron aluminide alloys based on Fe,AI have been formed by reaction synthesis from elemental powders followed by hot extrusion. The resulting alloys have approximately 2.5% by volume Al2O3 particles dispersed throughout the material. A proper combination of extrusion temperature, extrusion ratio, and post-consolidation heat treatment results in a secondary recrystallized microstructure with grain sizes greater than 25 mm. ODS material with 5%, Cr addition exhibits approximately one order of magnitude increase in time to failure at 650 degrees C compared to a similar alloy without the oxide dispersion. The activation energy for creep in the 5% Cr ODS material is of the order of 220 kJ/mol and the power law creep exponent is approximately 9.8. Transmission electron microscopy examination of the substructure of deformed samples indicates some formation of low angle dislocation boundaries, however, most of the dislocations are pinned at particles. The TEM observations and the value of the creep exponent are indicative of dislocation breakaway from particles as the rate controlling deformation mechanism. The TEM results indicate that particles smaller than approximately 50 nm and larger than approximately 500 nm do not contribute significantly to dislocation pinning. Addition of Nb and Mo along with Cr results in decreased minimum creep rates, however, the time to rupture is greatly reduced due to fracture at low strains initiated at large Nb particles that were not put into solution. (C) 1998 Elsevier Science S.A. All rights reserved. C1 Lockheed Martin Idaho Technol Co, Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. RP Wright, RN (reprint author), Lockheed Martin Idaho Technol Co, Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. OI Wright, Jill/0000-0001-8909-8144 NR 14 TC 9 Z9 9 U1 1 U2 2 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0921-5093 J9 MAT SCI ENG A-STRUCT JI Mater. Sci. Eng. A-Struct. Mater. Prop. Microstruct. Process. PD DEC 31 PY 1998 VL 258 IS 1-2 BP 285 EP 290 DI 10.1016/S0921-5093(98)00946-0 PG 6 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 153XA UT WOS:000077857500039 ER PT J AU Sikka, VK Blue, CA Sklad, SP Deevi, SC Shih, HR AF Sikka, VK Blue, CA Sklad, SP Deevi, SC Shih, HR TI Fabric cutting application of FeAl-based alloys SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article; Proceedings Paper CT International Symposium on Iron Aluminides - Alloy Design, Processing, Properties and Applications CY FEB 15-19, 1998 CL SAN ANTONIO, TEXAS SP Mat Sci Crit Technol Sector, Intermetall Mat Comm, ASM Int, Flow & Fracture Comm, TMS DE iron aluminide; FeAl; cutting; fabric; iron aluminides; nickel aluminides ID DUCTILITY; FRACTURE; MICROSTRUCTURE; DEFORMATION; HARDNESS AB Four intermetallic-based alloys were evaluated for cutting blade applications. These alloys included Fe3Al-based (FAS-II and FA-129), FeAl-based (PM-60) and Ni3Al-based (IC-50). These alloys were of interest because of their much higher work-hardening rates than the conventionally used carbon and stainless steels. The FeAl-based PM-60 alloy was of further interest because of its hardening possibility through retention of vacancies. The vacancy retention treatment is much simpler than the heat treatments used for hardening of steel blades. Blades of four intermetallic alloys and commercially used M2 tool steel blades were evaluated under identical conditions to cut two-ply heavy paper. Comparative results under identical conditions revealed that the FeAl-based alloy PM-60 outperformed the other intermetallic alloys and was equal to or somewhat better than the commercially used M2 tool steel. (C) Elsevier Science B.V. All rights reserved. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. Univ Virginia, Charlottesville, VA 22905 USA. Philip Morris Inc, Ctr Res Dev & Engn, Richmond, VA 23234 USA. Jackson State Univ, Jackson, MS 39217 USA. RP Sikka, VK (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, POB 2008, Oak Ridge, TN 37831 USA. NR 17 TC 4 Z9 5 U1 0 U2 1 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0921-5093 J9 MAT SCI ENG A-STRUCT JI Mater. Sci. Eng. A-Struct. Mater. Prop. Microstruct. Process. PD DEC 31 PY 1998 VL 258 IS 1-2 BP 325 EP 330 DI 10.1016/S0921-5093(98)00952-6 PG 6 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 153XA UT WOS:000077857500045 ER PT J AU Das, SR Trivedi, SP AF Das, SR Trivedi, SP TI Three brane action and the correspondence between N = 4 Yang Mills theory and anti-de Sitter space SO PHYSICS LETTERS B LA English DT Article ID BLACK-HOLES; ABSORPTION; SUPERGRAVITY AB Recently, a relation between N = 4 Super Yang Mills in 3 + 1 dimensions and supergravity in an AdS(5), background has been proposed. In this paper we explore the idea that the correspondence between operators in the Yang Mills theory and modes of the supergravity theory can be obtained by using the D3 brane action. Specifically, we consider two form, gauge fields for this purpose. The supergravity analysis predicts that the operator which corresponds to this mode has dimension six. We show that this is indeed the leading operator in the three brane Dirac-Born-Infeld and Wess-Zumino action which couples to this mode. It is important in the analysis that the brane action is expanded around the anti-de sitter background. Also, the Wess-Zumino term plays a crucial role in cancelling a lower dimension operator which appears in the the Dirac-Born-Infeld action. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Tata Inst Fundamental Res, Bombay 400005, Maharashtra, India. Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. RP Das, SR (reprint author), Tata Inst Fundamental Res, Homi Bhabha Rd, Bombay 400005, Maharashtra, India. NR 26 TC 36 Z9 36 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 J9 PHYS LETT B JI Phys. Lett. B PD DEC 31 PY 1998 VL 445 IS 1-2 BP 142 EP 149 DI 10.1016/S0370-2693(98)01450-6 PG 8 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 158WX UT WOS:000078141400021 ER PT J AU Loinaz, W Wells, JD AF Loinaz, W Wells, JD TI Higgs boson interactions in supersymmetric theories with large tan beta SO PHYSICS LETTERS B LA English DT Article DE Higgs boson; supersymmetry; collider phenomenology ID ELECTROWEAK SYMMETRY-BREAKING; STANDARD MODEL; MASS; PHENOMENOLOGY; UNIFICATION; DECAYS AB We show that radiative corrections to the Higgs potential in supersymmetric theories with large tan beta generically lead to large differences in the light Higgs boson decay branching fractions compared to those of the standard model Higgs boson. In contrast, the light Higgs boson production rates are largely unaffected. We identify Wh associated production followed by Higgs boson decays to photons or to leptons via WW* as potential experimental probes of these theories. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Virginia Tech, Inst Particle Phys & Astrophys, Dept Phys, Blacksburg, VA 24061 USA. Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Loinaz, W (reprint author), Virginia Tech, Inst Particle Phys & Astrophys, Dept Phys, Blacksburg, VA 24061 USA. OI Loinaz, William/0000-0001-7501-5002 NR 33 TC 34 Z9 34 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 J9 PHYS LETT B JI Phys. Lett. B PD DEC 31 PY 1998 VL 445 IS 1-2 BP 178 EP 184 DI 10.1016/S0370-2693(98)01483-X PG 7 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 158WX UT WOS:000078141400026 ER PT J AU Sheen, JP Whiteman, HH AF Sheen, JP Whiteman, HH TI Head and body size relationships in polymorphic tiger salamander larvae from Colorado SO COPEIA LA English DT Article ID AMBYSTOMA-TIGRINUM-NEBULOSUM; INTRASPECIFIC VARIATION; MORPHOLOGICAL VARIATION; WEST TEXAS; CANNIBALISM; DENSITY; MORPHS; SHAPE C1 Harvard Univ, Radcliffe Coll, Cambridge, MA 02138 USA. Rocky Mt Biol Lab, Crested Butte, CO 81224 USA. Savannah River Ecol Lab, Aiken, SC 29802 USA. Murray State Univ, Dept Biol Sci, Murray, KY 42071 USA. RP Sheen, JP (reprint author), Univ Calif Berkeley, Dept Integrat Biol, Berkeley, CA 94720 USA. NR 25 TC 5 Z9 5 U1 0 U2 2 PU AMER SOC ICHTHYOLOGISTS HERPETOLOGISTS PI CHARLESTON PA UNIV CHARLESTON, GRICE MARINE LABORATORY, 205 FORT JOHNSON RD, CHARLESTON, SC 29412 USA SN 0045-8511 J9 COPEIA JI Copeia PD DEC 30 PY 1998 IS 4 BP 1089 EP 1093 DI 10.2307/1447365 PG 5 WC Zoology SC Zoology GA 184VL UT WOS:000079634400036 ER PT J AU Mitchell, JA Reddy, JN AF Mitchell, JA Reddy, JN TI A multilevel hierarchical preconditioner for thin elastic solids SO INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING LA English DT Article DE multilevel; preconditioner; p finite elements; PCG; elastostatics; plates ID FINITE-ELEMENT SPACES; ELLIPTIC PROBLEMS; STRUCTURAL-ANALYSIS; MULTIGRID METHOD; 3 DIMENSIONS; CONSTRUCTION; APPROXIMATION; ALGORITHMS; SOLVERS AB In this study, a multilevel, recursively defined preconditioner, for use with the reconditioned Conjugate Gradient (PCG) algorithm in connection with the finite element analysis of elastostatics is developed. The preconditioner is constructed from a Sequence of hierarchical vector spaces arising from the p-version of the finite element method. Results from parametric studies evaluating the effects of skewed elements,orthotropic material properties, and extreme span ratios, for p = 2 and 3 are given. The results indicate that the preconditioner may be used to produce an efficient solver. The efficiency of the iterative procedure is illustrated using thin elastic solids. Results indicate that the preconditioner developed herein can be used to produce an efficient iterative solver for two- and three-dimensional problems in structural mechanics. (C) 1998 John Wiley & Sons, Ltd. C1 Texas A&M Univ, Dept Mech Engn, College Stn, TX 77843 USA. Sandia Natl Labs, Dept Mech & Mfg Engn, Albuquerque, NM 87185 USA. RP Reddy, JN (reprint author), Texas A&M Univ, Dept Mech Engn, College Stn, TX 77843 USA. RI Reddy, Junuthula/D-7737-2013 OI Reddy, Junuthula/0000-0002-9739-1639 NR 38 TC 7 Z9 7 U1 0 U2 0 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 0029-5981 J9 INT J NUMER METH ENG JI Int. J. Numer. Methods Eng. PD DEC 30 PY 1998 VL 43 IS 8 BP 1383 EP 1400 DI 10.1002/(SICI)1097-0207(19981230)43:8<1383::AID-NME473>3.0.CO;2-V PG 18 WC Engineering, Multidisciplinary; Mathematics, Interdisciplinary Applications SC Engineering; Mathematics GA 148DG UT WOS:000077488600002 ER PT J AU Blaum, K Geppert, C Muller, P Nortershauser, W Otten, EW Schmitt, A Trautmann, N Wendt, K Bushaw, BA AF Blaum, K Geppert, C Muller, P Nortershauser, W Otten, EW Schmitt, A Trautmann, N Wendt, K Bushaw, BA TI Properties and performance of a quadrupole mass filter used for resonance ionization mass spectrometry SO INTERNATIONAL JOURNAL OF MASS SPECTROMETRY LA English DT Article DE computer simulation; ion trajectories; isotopic abundance sensitivity; quadrupole mass spectrometer; resonance ionization mass spectrometry ID ORDER NONLINEAR RESONANCES; COMPUTER-SIMULATION; PAUL TRAP AB The performance of commercial quadrupole mass spectrometers (QMS) with a number of imperfections, as compared to the ideal hyperbolic geometry, has been characterized using the computer simulation program SIMION 3D version 6.0. The analysis of simulated QMS geometries focuses primarily on modeling of the internal potential, the study of field deviations, and the influence of finite length on performance of the QMS. The computer simulation of ion trajectories in the QMS field yields predictions for optimum working conditions and provides estimates for the resolving power and the maximum isotopic abundance sensitivity. Experimental measurements that confirm these expectations are presented. Optimization of the geometry and various operational parameters of the QMS is an important step in the development of a system for highly selective ultratrace determination using laser-based resonance ionization mass spectrometry. (Int J Mass Spectrom 181 (1998) 67-87) (C) 1998 Elsevier Science B.V. C1 Univ Mainz, Inst Phys, D-55099 Mainz, Germany. Univ Mainz, Inst Kernchem, D-55099 Mainz, Germany. Pacific NW Lab, Richland, WA 99352 USA. RP Blaum, K (reprint author), Univ Mainz, Inst Phys, D-55099 Mainz, Germany. RI Mueller, Peter/E-4408-2011; Wendt, Klaus/D-7306-2011; Nortershauser, Wilfried/A-6671-2013 OI Mueller, Peter/0000-0002-8544-8191; Wendt, Klaus/0000-0002-9033-9336; Nortershauser, Wilfried/0000-0001-7432-3687 NR 43 TC 44 Z9 45 U1 0 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 1387-3806 J9 INT J MASS SPECTROM JI Int. J. Mass Spectrom. PD DEC 30 PY 1998 VL 181 BP 67 EP 87 DI 10.1016/S1387-3806(98)14174-X PG 21 WC Physics, Atomic, Molecular & Chemical; Spectroscopy SC Physics; Spectroscopy GA 152FU UT WOS:000077766200008 ER PT J AU Pestovsky, O Bakac, A Espenson, JH AF Pestovsky, O Bakac, A Espenson, JH TI Kinetics and mechanism of the oxidation of 10-methyl-9,10-dihydroacridine by chromium(VI,V,IV): Electron vs hydrogen atom vs hydride transfer SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID NADH MODEL-COMPOUND; ACID-CATALYZED REDUCTION; OXOCHROMIUM(IV) ION; DERIVATIVES; CHEMISTRY; COMPLEXES; ANALOGS; OXYGEN; DIHYDROPYRIDINES; NICOTINAMIDE AB The oxidation of AcrH(2) to AcrH(+) by hydrogen chromate ions in H2O/MeCN (4:1, v/v) is a chain reaction that is strongly inhibited by oxygen. The initiation reaction between AcrH(2) (or AcrD(2)) and H2CrO4 forms AcrH(2)(.+) (or AcrD(2)(.+)) and occurs by a one-electron mechanism, k(H) = k(D) = 4.6 x 10(2) L mol(-1) s(-1) (25 degrees C). The Cr(V) produced along with AcrH(.) (from the acid ionization of AcrH(2)(.+)) are chain-carrying intermediates. The propagating reaction between AcrH(2) and Cr(V), k = 1 x 10(8) L mol(-1) s(-1), is of key importance since it is a branching reaction that yields two chain carriers, AcrH(.) and CrO2+, by hydrogen atom abstraction. The same partners react competitively by hydride ion abstraction, to yield Cr3+ and AcrH(+), k = 1.2 x 10(7) L mol(-1) s(-1), in the principal termination step. The reaction of CrO2+ and AcrH(2), k(H) = 1.0 x 10(4) and k(D) = 4.8 x 10(3) L mol(-1) s(-1), proceeds by hydride ion transfer. The Cr2+ so produced could be trapped as CrOO2+ when O-2 was present, thereupon terminating the chain. AcrH(2) itself reacts with Cr2O72- + H+, k = 5.6 x 10(3) L-2 mol(-2) s(-1), but this step is not an initiating reaction. Two successive electron-transfer steps are believed to occur between Cr2O72- and AcrH(2), yielding Cr-IV + Cr-VI + AcrH(+). C1 Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Chem, Ames, IA 50011 USA. RP Bakac, A (reprint author), Iowa State Univ, Ames Lab, Ames, IA 50011 USA. NR 49 TC 37 Z9 37 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0002-7863 J9 J AM CHEM SOC JI J. Am. Chem. Soc. PD DEC 30 PY 1998 VL 120 IS 51 BP 13422 EP 13428 DI 10.1021/ja9823464 PG 7 WC Chemistry, Multidisciplinary SC Chemistry GA 154DX UT WOS:000077874300019 ER PT J AU Bai, S Hu, JZ Pugmire, RJ Grant, DM Taylor, CMV Rubin, JB Peterson, EJ AF Bai, S Hu, JZ Pugmire, RJ Grant, DM Taylor, CMV Rubin, JB Peterson, EJ TI Solid state NMR and wide angle X-ray diffraction studies of supercritical fluid CO2-treated poly(ethylene terephthalate) SO MACROMOLECULES LA English DT Article ID TENSOR PRINCIPAL VALUES; CARBON-DIOXIDE; CHEMICAL-SHIFT; POLY(ETHYLENE-TEREPHTHALATE) FIBERS; MOLECULAR-ORIENTATION; GLASSY-POLYMERS; C-13 NMR; SPECTROSCOPY; TEMPERATURE; FILMS AB Poly(ethylene terephthalate) (PET) was treated with supercritical fluid (SCF) carbon dioxide to study crystallization of this polymer under SCF conditions. Solid state NMR spectroscopy and wide angle X-ray diffraction; (WAXD) detected dramatic changes in the PET molecular structure and motion after treatment. To fit WAXD data, the powder diffraction pattern for crystalline PET was calculated and is reported here for the first time. The WAXD results indicate an increase in crystallinity from essentially zero in the as-received sample to 62% in the SCF-treated sample. This large increase in the crystallinity of the SCF-treated PET was verified by the NMR relaxation measurements. The X-ray crystallite size, obtained from WAXD, was compared with those obtained from NMR proton spin diffusion measurements. The C-13 signals for aliphatic carbons (centered at 61.5 ppm) in the PET crystalline domain were resolved for the first time in a C-13 cross polarization/magic angle spinning spectrum (CP/MAS) due to the SCF treatment. The C-13 chemical shift tensors for PET were determined experimentally and were also compared to theoretical ab initio calculations. The anisotropic chemical shift data were then interpreted in terms of changes in the molecular conformation in PET as a result of SCF CO2 treatment. It was found that the SCF CO2 treatment is an effective method for enhancing the crystallinity of PET. These results in PET strongly support the previously proposed model for the existence of three motional regimes; crystalline, rigid amorphous, and mobile amorphous. C1 Univ Utah, Dept Chem, Salt Lake City, UT 84112 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Grant, DM (reprint author), Univ Utah, Dept Chem, Salt Lake City, UT 84112 USA. RI Hu, Jian Zhi/F-7126-2012 NR 43 TC 18 Z9 19 U1 1 U2 9 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0024-9297 J9 MACROMOLECULES JI Macromolecules PD DEC 29 PY 1998 VL 31 IS 26 BP 9238 EP 9246 DI 10.1021/ma9715031 PG 9 WC Polymer Science SC Polymer Science GA 153XU UT WOS:000077859300019 ER PT J AU McCoy, JD Curro, JG AF McCoy, JD Curro, JG TI Mapping of explicit atom onto united atom potentials SO MACROMOLECULES LA English DT Article ID INCLUDING INTERNAL-ROTATION; REPULSIVE FORCES; MOLECULAR FLUIDS; PHASE-EQUILIBRIA; LIQUID; SIMULATION; QUANTUM; ALKANES; POLYETHYLENE; ENERGIES AB Reversible work, also known as the potential of mean force, is used to map explicit atom (EA) onto united atom (UA) potentials for CH, CH2, CH3, and CH4 sites. These UA potentials are found to be temperature dependent and to be described by stretched exponential-6 functions. Although this is fairly dissimilar to the Lennard-Jones 6-12 potential, the one may be mapped onto the other by requiring that the second virial coefficients and locations of the potential minimum be equal for the two forms. When this is done, good agreement with standard UA potentials is found. C1 New Mexico Inst Min & Technol, Dept Mat & Met Engn, Socorro, NM 87801 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP New Mexico Inst Min & Technol, Dept Mat & Met Engn, Socorro, NM 87801 USA. RI McCoy, John/B-3846-2010 OI McCoy, John/0000-0001-5404-1404 NR 33 TC 49 Z9 51 U1 0 U2 8 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0024-9297 EI 1520-5835 J9 MACROMOLECULES JI Macromolecules PD DEC 29 PY 1998 VL 31 IS 26 BP 9362 EP 9368 DI 10.1021/ma981060g PG 7 WC Polymer Science SC Polymer Science GA 153XU UT WOS:000077859300033 ER PT J AU Anastassopoulos, DL Vradis, AA Toprakcioglu, C Smith, GS Dai, L AF Anastassopoulos, DL Vradis, AA Toprakcioglu, C Smith, GS Dai, L TI Neutron reflectivity study of end-attached telechelic polymers in a good solvent SO MACROMOLECULES LA English DT Article ID TRIBLOCK COPOLYMER CHAINS; BRUSHES; INTERFACE; SURFACES; FORCES; ADSORPTION; KINETICS; MICA C1 FORTH, GR-71110 Iraklion, Crete, Greece. Univ Patras, Dept Phys, GR-26500 Patras, Greece. Univ Calif Los Alamos Natl Lab, LANSCE, Los Alamos, NM 87545 USA. CSIRO, Div Chem & Polymers, Clayton, Vic 3169, Australia. RP Toprakcioglu, C (reprint author), FORTH, POB 1527, GR-71110 Iraklion, Crete, Greece. NR 18 TC 23 Z9 23 U1 0 U2 6 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0024-9297 J9 MACROMOLECULES JI Macromolecules PD DEC 29 PY 1998 VL 31 IS 26 BP 9369 EP 9371 DI 10.1021/ma980379y PG 3 WC Polymer Science SC Polymer Science GA 153XU UT WOS:000077859300034 ER PT J AU Huang, ZP Wu, JW Ren, ZF Wang, JH Siegal, MP Provencio, PN AF Huang, ZP Wu, JW Ren, ZF Wang, JH Siegal, MP Provencio, PN TI Growth of highly oriented carbon nanotubes by plasma-enhanced hot filament chemical vapor deposition SO APPLIED PHYSICS LETTERS LA English DT Article ID FIELD-EMISSION AB Highly oriented, multiwalled carbon nanotubes were grown on polished polycrystalline and single crystal nickel substrates by plasma enhanced hot filament chemical vapor deposition at temperatures below 666 degrees C. The carbon nanotubes range from 10 to 500 nm in diameter and 0.1 to 50 mu m in length depending on growth conditions. Acetylene is used as the carbon source for the growth of the carbon nanotubes and ammonia is used for dilution gas and catalysis. The plasma intensity, acetylene to ammonia gas ratio, and their flow rates, etc. affect the diameters and uniformity of the carbon nanotubes. (C) 1998 American Institute of Physics. [S0003-6951(98)01952-4]. C1 SUNY Buffalo, Dept Phys, Mat Synth Lab, Buffalo, NY 14260 USA. SUNY Buffalo, Dept Chem, Mat Synth Lab, Buffalo, NY 14260 USA. SUNY Buffalo, Ctr Adv Photon & Elect Mat, Buffalo, NY 14260 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Huang, ZP (reprint author), SUNY Buffalo, Dept Phys, Mat Synth Lab, Buffalo, NY 14260 USA. RI Ren, Zhifeng/B-4275-2014 NR 17 TC 232 Z9 236 U1 4 U2 45 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD DEC 28 PY 1998 VL 73 IS 26 BP 3845 EP 3847 DI 10.1063/1.122912 PG 3 WC Physics, Applied SC Physics GA 152RX UT WOS:000077791500015 ER PT J AU Gungor, MR Maroudas, D Gray, LJ AF Gungor, MR Maroudas, D Gray, LJ TI Effects of mechanical stress on electromigration-driven transgranular void dynamics in passivated metallic thin films SO APPLIED PHYSICS LETTERS LA English DT Article ID BAMBOO LINES; INTERCONNECTS; FAILURE; SIMULATION; MORPHOLOGY; CONDUCTORS; DIFFUSION; SOLIDS; SLITS; AL AB The combined effects of mechanical stress and surface electromigration on the dynamics of transgranular voids in passivated metallic thin films are analyzed based on self-consistent dynamical simulations. Depending on the strength of the electric and stress fields, void morphological instabilities can lead to film failure by propagation from the void surface of either faceted slits or finer-scale crack-like features. Most importantly, there exists a narrow range of applied stress for given strength of electric field over which slit formation can be inhibited completely. (C) 1998 American Institute of Physics. [S0003-6951(98)00352-0]. C1 Univ Calif Santa Barbara, Dept Chem Engn, Santa Barbara, CA 93106 USA. Oak Ridge Natl Lab, Comp Sci & Math Div, Oak Ridge, TN 37831 USA. RP Gungor, MR (reprint author), Univ Calif Santa Barbara, Dept Chem Engn, Santa Barbara, CA 93106 USA. EM dimitris@calypso.ucsb.edu NR 22 TC 32 Z9 32 U1 0 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD DEC 28 PY 1998 VL 73 IS 26 BP 3848 EP 3850 DI 10.1063/1.122913 PG 3 WC Physics, Applied SC Physics GA 152RX UT WOS:000077791500016 ER PT J AU Coronell, DG Hansen, DE Voter, AF Liu, CL Liu, XY Kress, JD AF Coronell, DG Hansen, DE Voter, AF Liu, CL Liu, XY Kress, JD TI Molecular dynamics-based ion-surface interaction models for ionized physical vapor deposition feature scale simulations SO APPLIED PHYSICS LETTERS LA English DT Article ID EMBEDDED-ATOM METHOD; FILMS AB A procedure is presented for incorporating the results of atomistic simulations of ion-surface interactions into integrated circuit topographic simulations of ionized physical vapor deposition (PVD). Energy and angular dependent sticking probabilities for energetic Cu atoms impacting a {111} Cu surface, obtained from molecular dynamics simulations, were implemented in a simple Monte Carlo flux model. The resulting flux-averaged Cu sticking probability was found to vary significantly with position within submicron features and with the feature geometry. This illustrates the shortcomings of a constant (energy and angle independent) sticking probability model for ionized PVD. (C) 1998 American Institute of Physics. [S0003-6951(98)02652-7]. C1 Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Motorola Inc, Semicond Prod Sector, Predict Engn Lab, Los Alamos, NM 87545 USA. Motorola Inc, Semicond Prod Sector, Predict Engn Lab, Austin, TX 78721 USA. RP Kress, JD (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. EM coronell@email.sps.mot.com; jkd@tiz.lanl.gov NR 13 TC 37 Z9 37 U1 0 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD DEC 28 PY 1998 VL 73 IS 26 BP 3860 EP 3862 DI 10.1063/1.122917 PG 3 WC Physics, Applied SC Physics GA 152RX UT WOS:000077791500020 ER PT J AU Abare, AC Mack, MP Hansen, M Speck, JS Coldren, LA DenBaars, SP Meyer, GA Lehew, SL Cooper, GA AF Abare, AC Mack, MP Hansen, M Speck, JS Coldren, LA DenBaars, SP Meyer, GA Lehew, SL Cooper, GA TI Measurement of gain current relations for InGaN multiple quantum wells SO APPLIED PHYSICS LETTERS LA English DT Article ID DIODES AB Pulsed operation of in-plane laser diodes with InGaN multiple quantum well active regions was achieved. For uncoated chemically assisted ion beam etched facets, we obtained threshold current densities as low as 10.6 kA/cm(2). The external differential quantum efficiency dependence on bar length was used to determine the internal optical loss and internal quantum efficiency of these devices and to calculate the modal gain in the device as a function of the terminal current density. Values of facet reflection were determined by a self-consistent analysis. We have measured 90 cm(-1) of modal gain and estimate material gain exceeding 900 cm(-1), at 20 kA/cm(2). (C) 1998 American Institute of Physics. [S0003-6951(98)00652- 4]. C1 Univ Calif Santa Barbara, Dept Elect & Comp Engn & Mat, Santa Barbara, CA 93106 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Abare, AC (reprint author), Univ Calif Santa Barbara, Dept Elect & Comp Engn & Mat, Santa Barbara, CA 93106 USA. RI Speck, James/H-5646-2011 NR 10 TC 8 Z9 8 U1 1 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD DEC 28 PY 1998 VL 73 IS 26 BP 3887 EP 3889 DI 10.1063/1.122925 PG 3 WC Physics, Applied SC Physics GA 152RX UT WOS:000077791500029 ER PT J AU Ren, F Hong, M Chu, SNG Marcus, MA Schurman, MJ Baca, A Pearton, SJ Abernathy, CR AF Ren, F Hong, M Chu, SNG Marcus, MA Schurman, MJ Baca, A Pearton, SJ Abernathy, CR TI Effect of temperature on Ga2O3(Gd2O3)/GaN metal-oxide-semiconductor field-effect transistors SO APPLIED PHYSICS LETTERS LA English DT Article ID N-TYPE GAN; ALGAN/GAN HFETS; FABRICATION AB Ga2O3(Gd2O3) was deposited on GaN for use as a gate dielectric in order to fabricate a depletion metal-oxide-semiconductor field-effect transistor (MOSFET). Analysis of the effect of temperature on the device shows that gate leakage is significantly reduced at elevated temperature relative to a conventional metal-semiconductor field-effect transistor fabricated on the same GaN layer. MOSFET device operation in fact improved upon heating to 400 degrees C. Modeling of the effect of temperature on contact resistance suggests that the improvement is due to a reduction in the parasitic resistances present in the device. (C) 1998 American Institute of Physics. [S0003-6951(98)02752-1]. C1 Univ Florida, Dept Chem Engn, Gainesville, FL 32606 USA. AT&T Bell Labs, Lucent Technol, Murray Hill, NJ 07974 USA. EMCORE Inc, Somerset, NJ 07061 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. Univ Florida, Dept Mat Sci & Engn, Gainesville, FL 32606 USA. RP Ren, F (reprint author), Univ Florida, Dept Chem Engn, Gainesville, FL 32606 USA. RI Hong, Minghwei/C-1433-2010 NR 25 TC 182 Z9 187 U1 4 U2 43 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD DEC 28 PY 1998 VL 73 IS 26 BP 3893 EP 3895 DI 10.1063/1.122927 PG 3 WC Physics, Applied SC Physics GA 152RX UT WOS:000077791500031 ER PT J AU Borrmann, H Campbell, J Dixon, DA Mercier, HPA Pirani, AM Schrobilgen, GJ AF Borrmann, H Campbell, J Dixon, DA Mercier, HPA Pirani, AM Schrobilgen, GJ TI Trigonal bipyramidal M(2)Ch(3)(2-) (M = Sn, Pb; Ch = S, Se, Te) and TlMTe33- anions: Multinuclear magnetic resonance, Raman spectroscopic, and theoretical studies, and the X-ray crystal structures of (2,2,2-crypt-K+)(3)TlPbTe33-center dot 2en and (2,2,2-crypt-K+)(2)Pb(2)Ch(3)(2-)center dot 0.5en (Ch = S, Se) SO INORGANIC CHEMISTRY LA English DT Article ID EFFECTIVE CORE POTENTIALS; MOLECULAR-STRUCTURE; CHALCOGENIDE ANIONS; METAL CLUSTERS; ZINTL ANIONS; ENERGIES; ORBITALS; PB-207; TE-125; SN-119 AB The series of group 14 metal trigonal bipyramidal anions has been extended to the mixed group 13/group 14 metal TlMTe33- anions (M = Sn, Pb), obtained by the reaction of Tl2M2Te3 and K2Te in en or in en/ethylamine mixtures and a stoichiometric excess of 2,2,2-crypt with respect to Kt. The thallium anions were characterized in solution by Sn-119, Tl-205, Pb-207, and Te-125 NMR spectroscopy. The small magnitudes of the relativistically corrected reduced coupling constants, (1)(KM-Ch)(RC) and (1)(KTl-Ch)(RC), observed for the previously reported MzChj2- (Ch Se, Te) and the TlMTe33- anions are consistent with predominantly p-bonded cages, and this observation is supported by local and nonlocal density functional theory (DFT) calculations. Theory indicates M-M and Tl-M interactions of high s character corresponding to Mayer bond orders of 0.13-0.32. The (KM-M)(RC) and (KTl-M)(RC) couplings are unusually large compared to those of the butterfly-shaped Tl(2)Ch(2)(2-) anions and likely arise from higher M-M and Tl-M bond orders, a larger number of coupling pathways, and smaller M-Ch-M and M-Ch-Tl bond angles. The TlPbTe33- anion has also been structurally characterized by X-ray crystallography in (2,2,2-crypt-K+)(3)TlPbTe33- . 2en [monoclinic system, space group P2(1)/c, Z = 4, a = 15.256(5) Angstrom, b = 26.487(9) Angstrom, c = 20.984(8) Angstrom, and beta = 93.03(3)degrees] along with Pb(2)Ch(3)(2-) (Ch = S, Se) in (2,2,2-crypt K+)(2)Pb(2)Ch(3)(2-). 0.5en [Pb2S32-: triclinic system, space group P (1) over bar, Z = 2, a = 10.189(2) Angstrom, b = 11.329(2) Angstrom, c = 23.194(4) Angstrom, alpha = 95.439(14)degrees, beta = 92.562(14)degrees, and gamma = 90.549(14)degrees; Pb2Se32-: triclinic system, space group P (1) over bar, Z = 2, a 10.187(2) Angstrom, b = 11.403(2) Angstrom, 23.360(6) Angstrom, alpha = 95.26(2)degrees, beta = 92.17(2)degrees, and gamma = 90.89(2)degrees]. Density functional theory calculations show that the experimental structures for the M(2)Ch(3)(2-) and TlPbTe33- anions are true minima and reproduce the experimental bond distances and angles. The vibrational frequencies determined by DFT calculations are in good agreement with those determined by Raman spectroscopy and have been used in their assignment. C1 McMaster Univ, Hamilton, ON L8S 4M1, Canada. Pacific NW Lab, William R Wiley Environm Mol Sci Lab, Richland, WA 99352 USA. Max Planck Inst Festkorperforsch, D-70569 Stuttgart, Germany. RP McMaster Univ, Hamilton, ON L8S 4M1, Canada. NR 70 TC 16 Z9 16 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0020-1669 EI 1520-510X J9 INORG CHEM JI Inorg. Chem. PD DEC 28 PY 1998 VL 37 IS 26 BP 6656 EP 6674 DI 10.1021/ic980574t PG 19 WC Chemistry, Inorganic & Nuclear SC Chemistry GA 153NL UT WOS:000077839100016 ER PT J AU Satcher, JH Olmstead, MM Droege, MW Parkin, SR Noll, BC May, L Balch, AL AF Satcher, JH Olmstead, MM Droege, MW Parkin, SR Noll, BC May, L Balch, AL TI Novel square arrangements in tetranuclear and octanuclear iron(III) complexes with asymmetric iron environments created by the unsymmetric bridging ligand N,N,N '-tris((N-methyl)-2-benzimidazolylmethyl)-N '-methyl-1,3-diamino-2-propanol SO INORGANIC CHEMISTRY LA English DT Article ID METHYLOSINUS-TRICHOSPORIUM OB3B; METHANE MONOOXYGENASE; MAGNETIC-PROPERTIES; RIBONUCLEOTIDE REDUCTASE; COORDINATION CHEMISTRY; CRYSTAL-STRUCTURE; OXO; BINUCLEAR; HYDROXYLASE; DIOXYGEN AB The synthesis and characterization of novel tetranuclear and octanuclear iron(III) complexes with structures based on a nearly square arrangement of four iron ions are reported. Reaction of ferric nitrate, Sodium acetate, and the unsymmetrical binucleating ligand HBMDP, where HBMDP is N,N,N'-tris((N-methyl)-2-benzimidazolylmethy)-N'-methyl-1,3-diamino-2-propanol, in acetone/water yields the tetranuclear iron complex [Fe-4(mu-O)(2)(mu-BMDP)(2)(mu-OAc)(2)](4+), which exhibits coordination number asymmetry. The structure of [Fe-4(mu-O)(2)(mu-BMDP)(2)(mu-OAc)(2)](NO3)(3)(OH). 12H(2)O has been determined by single-crystal X-ray diffraction. Each (mu-BMDP) ligand spans two iron(III) ions and causes these ions to become structurally distinct. Within this binuclear unit one iron atom is five-coordinate with distorted square pyramidal geometry and an N2O3 donor set, while the other iron is six-coordinate with distorted octahedral geometry and an N3O3 donor set. Two of these binuclear units are Linked through a pair of oxo and acetato bridges to form the centrosymmetric tetranuclear complex. The coordinatively nonequivalent iron atoms exhibit distinct Mossbauer spectroscopic parameters and produce a pair of doublets at 80 K. The iron(III) centers are coupled antiferromagnetically with a room-temperature moment of 1.9 mu(B) per iron with J = -103.3 cm(-1), zJ' = -105.9 cm(-1). The properties of the unsymmetric cation [Fe-4(mu-O)(2)(mu-BMDP)(2)(mu-OAc)(2)](4+) are similar to those observed for binuclear iron proteins with comparable coordinative inequivalence. Efforts to increase the solubility of [Fe-4(mu-O)(2)(mu-BMDP)(2)(mu-OAc)(2)](4+) by metathesis with sodium tetrafluoroborate resulted in the isolation of crystals of a new octanuclear iron species, [Fe-8(mu-O)(4)(mu-BMDP)(4)(OH)(4)(mu-OAc)(4)](BF4)(3)(OH). 2CH(3)CN . 8H(2)O (2), which has also been characterized by single-crystal X-ray diffraction. The asymmetric unit consists of an Fe-2(mu-O)(mu-BMDP)(mu-OAc) (OH) group which is externally bridged via the oxo ions to form a molecular square with four of the eight iron ions at the corners. Both iron sites are six-coordinate with distorted octahedral geometry. One has an N2O4 donor set; the other has an N3O3 donor set. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Catholic Univ Amer, Dept Chem, Washington, DC 20064 USA. Univ Calif Davis, Dept Chem, Davis, CA 95616 USA. RP Satcher, JH (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RI Parkin, Sean/E-7044-2011 NR 44 TC 36 Z9 36 U1 1 U2 4 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0020-1669 J9 INORG CHEM JI Inorg. Chem. PD DEC 28 PY 1998 VL 37 IS 26 BP 6751 EP 6758 PG 8 WC Chemistry, Inorganic & Nuclear SC Chemistry GA 153NL UT WOS:000077839100028 ER PT J AU Zauche, TH Espenson, JH AF Zauche, TH Espenson, JH TI Oxidation of alcohols by hydrogen peroxide, catalyzed by methyltrioxorhenium (MTO): A hydride abstraction SO INORGANIC CHEMISTRY LA English DT Article ID METHYLRHENIUM TRIOXIDE; MECHANISM; DIMETHYLDIOXIRANE; SECONDARY; KINETICS; ALKANES AB Primary and secondary alcohols are oxidized using hydrogen peroxide as an oxygen donor and methyltrioxorhenium (MTO) as a catalyst. The methylrhenium di-peroxide, CH(3)Re(O)(eta(2)-O(2))(2)(H(2)O), was the dominant and reactive form of the catalyst. Representative rate constants k/L mol(-1) s(-1) are 1.02 x 10(-4) for 4-Me-alpha-methylbenzyl alcohol and 4.9 x 10(-5) for 4-Cl-alpha-methylbenzyl alcohol. There was a kinetic isotope effect of 3.2 for the alpha C-H bond. When sec-phenethyl alcohol was labeled with (18)O, 80% of the oxygen was retained in the ketone. Tests for the possible intervention of a free radical intermediate were carried out; the evidence was entirety negative. A mechanism featuring hydride abstraction is proposed, the first time for the H(2)O(2)/MTO system. Also, a cocatalytic set of reaction conditions has been developed on the synthetic scale, using bromide and MTO as cocatalysts, which cuts the reaction time from hours to minutes. C1 Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Chem, Ames, IA 50011 USA. RP Espenson, JH (reprint author), Iowa State Univ, Ames Lab, Ames, IA 50011 USA. NR 26 TC 44 Z9 44 U1 0 U2 14 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0020-1669 J9 INORG CHEM JI Inorg. Chem. PD DEC 28 PY 1998 VL 37 IS 26 BP 6827 EP 6831 DI 10.1021/ic9806784 PG 5 WC Chemistry, Inorganic & Nuclear SC Chemistry GA 153NL UT WOS:000077839100037 ER PT J AU LaGattuta, KJ Cohen, JS AF LaGattuta, KJ Cohen, JS TI Quasiclassical modelling of helium double photoionization SO JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS LA English DT Article ID NONSEQUENTIAL DOUBLE-IONIZATION; MULTIPLE IONIZATION; FIELD; ATOMS; CLUSTERS AB We applied the method known as fermion molecular dynamics (FMD) to the description of a helium atom interacting with a short pulse of intense, long-wavelength laser radiation, for both linear and circular polarization. We describe the results of these calculations, insofar as they bear on the question of the mechanisms leading to double electron ejection. In the case of linear polarization, boomeranging trajectories leading to double ionization were observed at all laser intensities above threshold. The probability of occurrence was low and almost independent of laser intensity. However, very near to threshold, boomeranging trajectories leading to double ionization were found to occur with a probability comparable to that for all other independent electron (sequential) processes. This produced a shoulder in the curve of double ionization probability versus laser intensity. The size of this shoulder was found to depend on laser wavelength and pulse length. No such trajectories were found for circular polarization. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP LaGattuta, KJ (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 18 TC 43 Z9 43 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0953-4075 J9 J PHYS B-AT MOL OPT JI J. Phys. B-At. Mol. Opt. Phys. PD DEC 28 PY 1998 VL 31 IS 24 BP 5281 EP 5291 DI 10.1088/0953-4075/31/24/010 PG 11 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 155YK UT WOS:000077974200010 ER PT J AU Timmermans, E AF Timmermans, E TI Phase separation of Bose-Einstein condensates SO PHYSICAL REVIEW LETTERS LA English DT Article ID ATOMS; GAS AB We distinguish two types of spatial separation exhibited by atomic trap Bose-Einstein condensates: potential separation, in which case the condensates diffuse into each other as the trap is opened adiabatically, and phase separation, in which case the separation persists in the absence of external potentials. We discuss relevant features of the dynamics and statics of the phase separation of dilute condensates. C1 Harvard Smithsonian Ctr Astrophys, Inst Theoret Atom & Mol Phys, Cambridge, MA 02138 USA. RP Timmermans, E (reprint author), Univ Calif Los Alamos Natl Lab, T-4,MS B-268, Los Alamos, NM 87545 USA. NR 16 TC 262 Z9 264 U1 0 U2 3 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD DEC 28 PY 1998 VL 81 IS 26 BP 5718 EP 5721 DI 10.1103/PhysRevLett.81.5718 PG 4 WC Physics, Multidisciplinary SC Physics GA 152DG UT WOS:000077760200004 ER PT J AU Baltz, AJ Goldhaber, AS Goldhaber, M AF Baltz, AJ Goldhaber, AS Goldhaber, M TI Solar neutrino puzzle: An oscillation solution with maximal neutrino mixing SO PHYSICAL REVIEW LETTERS LA English DT Article ID MATTER OSCILLATIONS; MASS; EARTH AB If, as suggested by the Super-Kamiokande results, nu(mu), and nu(tau) are maximally and "rapidly" (Delta m(2) approximate to 2.2 x 10(-3) eV(2)) mixed, this alone determines the mapping from current to mass eigenstates up to one rotation angle theta mixing nu(e) "more slowly" with a particular, equal-weight combination of nu(mu) and nu(tau). For sin 2 theta = 1, the resulting minimal number of free parameters, yet maximal mixing, shows agreement, with minor modifications, between extant observations of solar neutrinos and predictions by the standard solar model. C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. SUNY Stony Brook, Inst Theoret Phys, Stony Brook, NY 11794 USA. RP Baltz, AJ (reprint author), Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. NR 38 TC 208 Z9 208 U1 1 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD DEC 28 PY 1998 VL 81 IS 26 BP 5730 EP 5733 DI 10.1103/PhysRevLett.81.5730 PG 4 WC Physics, Multidisciplinary SC Physics GA 152DG UT WOS:000077760200007 ER PT J AU He, XG Hou, WS Yang, KC AF He, XG Hou, WS Yang, KC TI Prospects for direct CP violation in exclusive and inclusive charmless B decays SO PHYSICAL REVIEW LETTERS LA English DT Article ID SEMILEPTONIC BRANCHING RATIO; 2-HIGGS-DOUBLET MODELS; PHYSICS AB Within the standard model, CP rate asymmetries for B --> K(-)pi(+,0) could reach 10%. With strong final state phases, they could go up to 20%-30%, even for the (K) over bar(0)pi(-) mode which would have the opposite sign. We can account for K(-)pi(+), (K) over bar(0)pi(-), and phi K rate data with new physics enhanced color dipole coupling and destructive interference. Asymmetries could reach 40%-60% for K pi and phi K modes and are all of the same sign. We are unable to account for the K(-)pi(0) rate. Our inclusive study supports our exclusive results. C1 Natl Taiwan Univ, Dept Phys, Taipei 10764, Taiwan. Univ Melbourne, Sch Phys, Parkville, Vic 3052, Australia. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Acad Sinica, Inst Phys, Taipei, Taiwan. RP He, XG (reprint author), Natl Taiwan Univ, Dept Phys, Taipei 10764, Taiwan. RI He, Xiao-Gang/C-8894-2013; He, Xiao-Gang/P-2242-2015 NR 17 TC 19 Z9 19 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD DEC 28 PY 1998 VL 81 IS 26 BP 5738 EP 5741 DI 10.1103/PhysRevLett.81.5738 PG 4 WC Physics, Multidisciplinary SC Physics GA 152DG UT WOS:000077760200009 ER PT J AU Abe, F Akimoto, H Akopian, A Albrow, MG Amadon, A Amendolia, SR Amidei, D Antos, J Aota, S Apollinari, G Arisawa, T Asakawa, T Ashmanskas, W Atac, M Azzi-Bacchetta, P Bacchetta, N Bagdasarov, S Bailey, MW de Barbaro, P Barbaro-Galtieri, A Barnes, VE Barnett, BA Barone, M Bauer, G Baumann, T Bedeschi, F Behrends, S Belforte, S Bellettini, G Bellinger, J Benjamin, D Bensinger, J Beretvas, A Berge, JP Berryhill, J Bertolucci, S Bettelli, S Bevensee, B Bhatti, A Biery, K Bigongiari, C Binkley, M Bisello, D Blair, RE Blocker, C Bloom, K Busk, S Bodek, A Bokhari, W Bolla, G Bonushkin, Y Bortoletto, D Boudreau, J Breccia, L Bromberg, C Bruner, N Brunetti, R Buckley-Geer, E Budd, HS Burkett, K Busetto, G Byon-Wagner, A Byrum, KL Campbell, M Caner, A Carithers, W Carlsmith, D Cassada, J Castro, A Cauz, D Cerri, A Chang, PS Chang, PT Chao, HY Chapman, J Cheng, MT Chertok, M Chiarelli, G Chiou, CN Chlebana, F Christofek, L Cropp, R Chu, ML Cihangir, S Clark, AG Cobal, M Cocca, E Contreras, M Conway, J Cooper, J Cordelli, M Costanzo, D Couyoumtzelis, C Cronin-Hennessy, D Culbertson, R Dagenhart, D Daniels, T DeJongh, F Dell'Agnello, S Dell'Orso, M Demina, R Demortier, L Deninno, M Derwent, PF Devlin, T Dittmann, JR Donati, S Done, J Dorigo, T Eddy, N Einsweiler, K Elias, JE Ely, R Engels, E Erdmann, W Errede, D Errede, S Fan, Q Feild, RG Feng, Z Ferretti, C Fiori, I Flaugher, B Foster, GW Franklin, M Freeman, J Friedman, J Frisch, H Fukui, Y Gadomski, S Galeotti, S Gallinaro, M Gane, O Garcia-Sciveres, M Garfinkel, AF Gay, C Geer, S Gerdes, DW Giannetti, P Giokaris, N Giromini, P Giusti, G Gold, M Gordon, A Goshaw, AT Gotra, Y Goulianos, K Grassmann, H Groer, L Grosso-Pilcher, C Guillian, G da Costa, JG Guo, RS Haber, C Hafen, E Hahn, SR Hamilton, R Handa, T Handler, R Happacher, F Hao, W Hara, K Hardman, AD Harris, RM Hartmann, F Hauser, J Hayashi, E Heinrich, J Heiss, A Hinrichsen, B Hoffman, KD Hohlmann, M Holck, C Hollebeek, R Holloway, L Huang, Z Huffman, BT Hughes, R Huston, J Huth, J Ikeda, H Incagli, M Incandela, J Introzzi, G Iwai, J Iwata, Y James, E Jensen, H Joshi, U Kajfasz, E Kambara, H Kamon, T Kaneko, T Karr, K Kasha, H Kato, Y Keaffaber, TA Kelley, K Kennedy, RD Kephart, R Kestenbaum, D Khazins, D Kikuchi, T Kim, BJ Kim, HS Kim, SH Kim, YK Kirsch, L Klimenko, S Knoblauch, D Koehn, P Kongeter, A Kondo, K Konigsberg, J Kordas, K Korytov, A Kovacs, E Kowald, W Kroll, J Kruse, M Kuhlmann, SE Kuns, E Kurino, K Kuwabara, T Laasanen, AT Lami, S Lammel, S Lamoureux, JI Lancaster, M Lanzoni, M Latino, G LeCompte, T Leone, S Lewis, JD Lindgren, M Liss, TM Liu, JB Liu, YC Lockyer, N Long, O Loomis, C Loreti, M Lucchesi, D Lukens, P Lusin, S Lys, J Maeshima, K Maksimovic, P Mangano, M Mariotti, M Marriner, JP Martignon, G Martin, A Matthews, JAJ Mazzanti, P McFarland, K McIntyre, P Melese, P Menguzzato, M Menzione, A Meschi, E Metzler, S Miao, C Miao, T Michail, G Miller, R Minato, H Miscetti, S Mishina, M Miyashita, S Moggi, N Moore, E Morita, Y Mukherjee, A Muller, T Murat, P Murgia, S Musy, M Nakada, H Nakaya, T Nakano, I Nelson, C Neuberger, D Newman-Holmes, C Ngan, CYP Nodulman, L Nomerotski, A Oh, SH Ohmoto, T Ohsugi, T Oishi, R Okabe, M Okusawa, T Olsen, J Pagliarone, C Paoletti, R Papadimitriou, V Pappas, SP Parashar, N Parri, A Patrick, J Pauletta, G Paulini, M Perazzo, A Pescara, L Peters, MD Phillips, TJ Piacentino, G Pillai, M Pitts, KT Plunkett, R Pompos, A Pondrom, L Proudfoot, J Ptohos, F Punzi, G Ragan, K Reher, D Reischl, M Ribon, A Rimondi, F Ristori, L Robertson, WJ Robinson, A Rodrigo, T Rolli, S Rosenson, L Roser, R Saab, T Sakumoto, WK Saltzberg, D Sansoni, A Santi, L Sato, H Schlabach, P Schmidt, EE Schmidt, MP Scott, A Scribano, A Segler, S Seidel, S Seiya, Y Semeria, F Shah, T Shapiro, MD Shaw, NM Shepard, PF Shibayama, T Shimojima, M Shochet, M Siegrist, J Sill, A Sinervo, P Singh, P Sliwa, K Smith, C Snider, FD Spalding, J Speer, T Sphicas, P Spinella, F Spiropulu, M Spiegel, L Stanco, L Steele, J Stefanini, A Strohmer, R Strologas, J Strumia, F Stuart, D Sumorok, K Suzuki, J Suzuki, T Takahashi, T Takano, T Takashima, R Takikawa, K Tanaka, M Tannenbaum, B Tartarelli, F Taylor, W Tecchio, M Teng, PK Teramoto, Y Terashi, K Tether, S Theriot, D Thomas, TL Thurman-Keup, R Timko, M Tipton, P Titov, A Tkaczyk, S Toback, D Tollefson, K Tollestrup, A Toyoda, H Trischuk, W de Troconiz, JF Truitt, S Tseng, J Turini, N Uchida, T Ukegawa, F Valls, J van den Brink, SC Vejcik, S Velev, G Vidal, R Vilar, R Vucinic, D Wagner, RG Wagner, RL Wahl, J Wallace, NB Walsh, AM Wang, C Wang, CH Wang, MJ Warburton, A Watanabe, T Watts, T Webb, R Wei, C Wenzel, H Wester, WC Wicklund, AB Wicklund, E Wilkinson, R Williams, HH Wilson, P Winer, BL Winn, D Wolinski, D Wolinski, J Worm, S Wu, X Wyss, J Yagil, A Yao, W Yasuoka, K Yeh, GP Yeh, P Yoh, J Yosef, C Yoshida, T Yu, I Zanetti, A Zetti, F Zucchelli, S AF Abe, F Akimoto, H Akopian, A Albrow, MG Amadon, A Amendolia, SR Amidei, D Antos, J Aota, S Apollinari, G Arisawa, T Asakawa, T Ashmanskas, W Atac, M Azzi-Bacchetta, P Bacchetta, N Bagdasarov, S Bailey, MW de Barbaro, P Barbaro-Galtieri, A Barnes, VE Barnett, BA Barone, M Bauer, G Baumann, T Bedeschi, F Behrends, S Belforte, S Bellettini, G Bellinger, J Benjamin, D Bensinger, J Beretvas, A Berge, JP Berryhill, J Bertolucci, S Bettelli, S Bevensee, B Bhatti, A Biery, K Bigongiari, C Binkley, M Bisello, D Blair, RE Blocker, C Bloom, K Busk, S Bodek, A Bokhari, W Bolla, G Bonushkin, Y Bortoletto, D Boudreau, J Breccia, L Bromberg, C Bruner, N Brunetti, R Buckley-Geer, E Budd, HS Burkett, K Busetto, G Byon-Wagner, A Byrum, KL Campbell, M Caner, A Carithers, W Carlsmith, D Cassada, J Castro, A Cauz, D Cerri, A Chang, PS Chang, PT Chao, HY Chapman, J Cheng, MT Chertok, M Chiarelli, G Chiou, CN Chlebana, F Christofek, L Cropp, R Chu, ML Cihangir, S Clark, AG Cobal, M Cocca, E Contreras, M Conway, J Cooper, J Cordelli, M Costanzo, D Couyoumtzelis, C Cronin-Hennessy, D Culbertson, R Dagenhart, D Daniels, T DeJongh, F Dell'Agnello, S Dell'Orso, M Demina, R Demortier, L Deninno, M Derwent, PF Devlin, T Dittmann, JR Donati, S Done, J Dorigo, T Eddy, N Einsweiler, K Elias, JE Ely, R Engels, E Erdmann, W Errede, D Errede, S Fan, Q Feild, RG Feng, Z Ferretti, C Fiori, I Flaugher, B Foster, GW Franklin, M Freeman, J Friedman, J Frisch, H Fukui, Y Gadomski, S Galeotti, S Gallinaro, M Gane, O Garcia-Sciveres, M Garfinkel, AF Gay, C Geer, S Gerdes, DW Giannetti, P Giokaris, N Giromini, P Giusti, G Gold, M Gordon, A Goshaw, AT Gotra, Y Goulianos, K Grassmann, H Groer, L Grosso-Pilcher, C Guillian, G da Costa, JG Guo, RS Haber, C Hafen, E Hahn, SR Hamilton, R Handa, T Handler, R Happacher, F Hao, W Hara, K Hardman, AD Harris, RM Hartmann, F Hauser, J Hayashi, E Heinrich, J Heiss, A Hinrichsen, B Hoffman, KD Hohlmann, M Holck, C Hollebeek, R Holloway, L Huang, Z Huffman, BT Hughes, R Huston, J Huth, J Ikeda, H Incagli, M Incandela, J Introzzi, G Iwai, J Iwata, Y James, E Jensen, H Joshi, U Kajfasz, E Kambara, H Kamon, T Kaneko, T Karr, K Kasha, H Kato, Y Keaffaber, TA Kelley, K Kennedy, RD Kephart, R Kestenbaum, D Khazins, D Kikuchi, T Kim, BJ Kim, HS Kim, SH Kim, YK Kirsch, L Klimenko, S Knoblauch, D Koehn, P Kongeter, A Kondo, K Konigsberg, J Kordas, K Korytov, A Kovacs, E Kowald, W Kroll, J Kruse, M Kuhlmann, SE Kuns, E Kurino, K Kuwabara, T Laasanen, AT Lami, S Lammel, S Lamoureux, JI Lancaster, M Lanzoni, M Latino, G LeCompte, T Leone, S Lewis, JD Lindgren, M Liss, TM Liu, JB Liu, YC Lockyer, N Long, O Loomis, C Loreti, M Lucchesi, D Lukens, P Lusin, S Lys, J Maeshima, K Maksimovic, P Mangano, M Mariotti, M Marriner, JP Martignon, G Martin, A Matthews, JAJ Mazzanti, P McFarland, K McIntyre, P Melese, P Menguzzato, M Menzione, A Meschi, E Metzler, S Miao, C Miao, T Michail, G Miller, R Minato, H Miscetti, S Mishina, M Miyashita, S Moggi, N Moore, E Morita, Y Mukherjee, A Muller, T Murat, P Murgia, S Musy, M Nakada, H Nakaya, T Nakano, I Nelson, C Neuberger, D Newman-Holmes, C Ngan, CYP Nodulman, L Nomerotski, A Oh, SH Ohmoto, T Ohsugi, T Oishi, R Okabe, M Okusawa, T Olsen, J Pagliarone, C Paoletti, R Papadimitriou, V Pappas, SP Parashar, N Parri, A Patrick, J Pauletta, G Paulini, M Perazzo, A Pescara, L Peters, MD Phillips, TJ Piacentino, G Pillai, M Pitts, KT Plunkett, R Pompos, A Pondrom, L Proudfoot, J Ptohos, F Punzi, G Ragan, K Reher, D Reischl, M Ribon, A Rimondi, F Ristori, L Robertson, WJ Robinson, A Rodrigo, T Rolli, S Rosenson, L Roser, R Saab, T Sakumoto, WK Saltzberg, D Sansoni, A Santi, L Sato, H Schlabach, P Schmidt, EE Schmidt, MP Scott, A Scribano, A Segler, S Seidel, S Seiya, Y Semeria, F Shah, T Shapiro, MD Shaw, NM Shepard, PF Shibayama, T Shimojima, M Shochet, M Siegrist, J Sill, A Sinervo, P Singh, P Sliwa, K Smith, C Snider, FD Spalding, J Speer, T Sphicas, P Spinella, F Spiropulu, M Spiegel, L Stanco, L Steele, J Stefanini, A Strohmer, R Strologas, J Strumia, F Stuart, D Sumorok, K Suzuki, J Suzuki, T Takahashi, T Takano, T Takashima, R Takikawa, K Tanaka, M Tannenbaum, B Tartarelli, F Taylor, W Tecchio, M Teng, PK Teramoto, Y Terashi, K Tether, S Theriot, D Thomas, TL Thurman-Keup, R Timko, M Tipton, P Titov, A Tkaczyk, S Toback, D Tollefson, K Tollestrup, A Toyoda, H Trischuk, W de Troconiz, JF Truitt, S Tseng, J Turini, N Uchida, T Ukegawa, F Valls, J van den Brink, SC Vejcik, S Velev, G Vidal, R Vilar, R Vucinic, D Wagner, RG Wagner, RL Wahl, J Wallace, NB Walsh, AM Wang, C Wang, CH Wang, MJ Warburton, A Watanabe, T Watts, T Webb, R Wei, C Wenzel, H Wester, WC Wicklund, AB Wicklund, E Wilkinson, R Williams, HH Wilson, P Winer, BL Winn, D Wolinski, D Wolinski, J Worm, S Wu, X Wyss, J Yagil, A Yao, W Yasuoka, K Yeh, GP Yeh, P Yoh, J Yosef, C Yoshida, T Yu, I Zanetti, A Zetti, F Zucchelli, S CA CDF Collaboration TI Search for the decays B-s(0),B-d(0)-> e(+/-)mu(-/+) and Pati-Salam leptoquarks SO PHYSICAL REVIEW LETTERS LA English DT Article ID 2 CHARGED LEPTONS; MESON DECAYS; COLLISIONS; DETECTOR AB We have searched for the decays B-s(0) --> e(+/-)mu(-/+) and B-d(0) --> e(+/-)mu(-/+) using a 102 pb(-1) data sample of p (p) over bar collisions at root s = 1.8 TeV collected with the Collider Detector at Fermilab. We set upper limits on the branching fractions of B(B-s(0) --> e(+/-)mu(-/+)) < 6.1(8.2) x 10(-6) and B(B-d(0) --> e(+/-)mu(-/+)) < 3.5(4.5) x 10(-6) at 90(95)% confidence level. Using these limits, we set lower bounds on the corresponding Pati-Salam leptoquark masses and find that M-LQ(B-s(0)) > 20.7(19.3) TeV/c(2) and M-LQ(B-d(0)) > 21.7(20.4) TeV/c(2) at 90(95)% confidence level. C1 Kek Nat Lab High Energy Phys, Tsukuba, Ibaraki 305, Japan. Argonne Natl Lab, Argonne, IL 60439 USA. Univ Bologna, Ist Nazl Fis Nucl, I-40127 Bologna, Italy. Brandeis Univ, Waltham, MA 02254 USA. Univ Calif Los Angeles, Los Angeles, CA 90024 USA. Univ Chicago, Chicago, IL 60637 USA. Duke Univ, Durham, NC 27708 USA. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Florida, Gainesville, FL 32611 USA. Ist Nazl Fis Nucl, Lab Nazl Frascati, I-00044 Frascati, Italy. Univ Geneva, CH-1211 Geneva 4, Switzerland. Harvard Univ, Cambridge, MA 02138 USA. Hiroshima Univ, Higashihiroshima 724, Japan. Univ Illinois, Urbana, IL 61801 USA. McGill Univ, Inst Particle Phys, Montreal, PQ H3A 2T8, Canada. Univ Toronto, Toronto, ON M5S 1A7, Canada. Johns Hopkins Univ, Baltimore, MD 21218 USA. Univ Karlsruhe, Inst Expt Kernphys, D-76128 Karlsruhe, Germany. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. MIT, Cambridge, MA 02139 USA. Univ Michigan, Ann Arbor, MI 48109 USA. Michigan State Univ, E Lansing, MI 48824 USA. Univ New Mexico, Albuquerque, NM 87131 USA. Ohio State Univ, Columbus, OH 43210 USA. Osaka City Univ, Osaka 588, Japan. Univ Padua, Ist Nazl Fis Nucl, Sez Padova, I-35131 Padua, Italy. Univ Penn, Philadelphia, PA 19104 USA. Univ Pisa, Ist Nazl Fis Nucl, I-56100 Pisa, Italy. Scuola Normale Super Pisa, I-56100 Pisa, Italy. Univ Pittsburgh, Pittsburgh, PA 15260 USA. Purdue Univ, W Lafayette, IN 47907 USA. Univ Rochester, Rochester, NY 14627 USA. Rockefeller Univ, New York, NY 10021 USA. Rutgers State Univ, Piscataway, NJ 08855 USA. Acad Sinica, Taipei 11530, Taiwan. Texas A&M Univ, College Stn, TX 77843 USA. Texas Tech Univ, Lubbock, TX 79409 USA. Univ Trieste, Ist Nazl Fis Nucl, Udine, Italy. Univ Tsukuba, Tokyo, Ibaraki 315, Japan. Tufts Univ, Medford, MA 02155 USA. Waseda Univ, Tokyo 169, Japan. Univ Wisconsin, Madison, WI 53706 USA. Yale Univ, New Haven, CT 06520 USA. RP Abe, F (reprint author), Kek Nat Lab High Energy Phys, Tsukuba, Ibaraki 305, Japan. RI Lancaster, Mark/C-1693-2008; Vucinic, Dejan/C-2406-2008; Nomerotski, Andrei/A-5169-2010; Azzi, Patrizia/H-5404-2012; Punzi, Giovanni/J-4947-2012; Chiarelli, Giorgio/E-8953-2012; Warburton, Andreas/N-8028-2013; Paulini, Manfred/N-7794-2014; Introzzi, Gianluca/K-2497-2015; vilar, rocio/D-7454-2014; Tartarelli, Giuseppe Francesco/A-5629-2016; OI Latino, Giuseppe/0000-0002-4098-3502; Wyss, Jeffery/0000-0002-8277-4012; Lancaster, Mark/0000-0002-8872-7292; Bertolucci, Sergio/0000-0003-1738-4736; Bigongiari, Ciro/0000-0003-3293-8522; Azzi, Patrizia/0000-0002-3129-828X; Punzi, Giovanni/0000-0002-8346-9052; Chiarelli, Giorgio/0000-0001-9851-4816; Warburton, Andreas/0000-0002-2298-7315; Paulini, Manfred/0000-0002-6714-5787; Introzzi, Gianluca/0000-0002-1314-2580; Tartarelli, Giuseppe Francesco/0000-0002-4244-502X; Meschi, Emilio/0000-0003-4502-6151 NR 21 TC 18 Z9 18 U1 0 U2 4 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD DEC 28 PY 1998 VL 81 IS 26 BP 5742 EP 5747 DI 10.1103/PhysRevLett.81.5742 PG 6 WC Physics, Multidisciplinary SC Physics GA 152DG UT WOS:000077760200010 ER PT J AU Abe, F Akimoto, H Akopian, A Albrow, MG Amadon, A Amendolia, SR Amidei, D Antos, J Aota, S Apollinari, G Arisawa, T Asakawa, T Ashmanskas, W Atac, M Azzi-Bacchetta, P Bacchetta, N Bagdasarov, S Bailey, MW de Barbaro, P Barbaro-Galtieri, A Barnes, VE Barnett, BA Barone, M Bauer, G Baumann, T Bedeschi, F Behrends, S Belforte, S Bellettini, G Bellinger, J Benjamin, D Bensinger, J Beretvas, A Berge, JP Berryhill, J Bertolucci, S Bettelli, S Bevensee, B Bhatti, A Biery, K Bigongiari, C Binkley, M Bisello, D Blair, RE Blocker, C Bloom, K Busk, S Bodek, A Bokhari, W Bolla, G Bonushkin, Y Bortoletto, D Boudreau, J Breccia, L Bromberg, C Bruner, N Brunetti, R Buckley-Geer, E Budd, HS Burkett, K Busetto, G Byon-Wagner, A Byrum, KL Campbell, M Caner, A Carithers, W Carlsmith, D Cassada, J Castro, A Cauz, D Cerri, A Chang, PS Chang, PT Chao, HY Chapman, J Cheng, MT Chertok, M Chiarelli, G Chiou, CN Chlebana, F Christofek, L Chu, ML Cihangir, S Clark, AG Cobal, M Cocca, E Contreras, M Conway, J Cooper, J Cordelli, M Costanzo, D Couyoumtzelis, C Cronin-Hennessy, D Culbertson, R Dagenhart, D Daniels, T DeJongh, F Dell'Agnello, S Dell'Orso, M Demina, R Demortier, L Deninno, M Derwent, PF Devlin, T Dittmann, JR Donati, S Done, J Dorigo, T Eddy, N Einsweiler, K Elias, JE Ely, R Engels, E Erdmann, W Errede, D Errede, S Fan, Q Feild, RG Feng, Z Ferretti, C Fiori, I Flaugher, B Foster, GW Franklin, M Freeman, J Friedman, J Frisch, H Fukui, Y Gadomski, S Galeotti, S Gallinaro, M Ganel, O Garcia-Sciveres, M Garfinkel, AF Gay, C Geer, S Gerdes, DW Giannetti, P Giokaris, N Giromini, P Giusti, G Gold, M Gordon, A Goshaw, AT Gotra, Y Goulianos, K Grassmann, H Groer, L Grosso-Pilcher, C Guillian, G da Costa, JG Guo, RS Haber, C Hafen, E Hahn, SR Hamilton, R Handa, T Handler, R Happacher, F Hara, K Hardman, AD Harris, RM Hartmann, F Hauser, J Hayashi, E Heinrich, J Hao, W Hinrichsen, B Hoffman, KD Hohlmann, M Holck, C Hollebeek, R Holloway, L Huang, Z Huffman, BT Hughes, R Huston, J Huth, J Ikeda, H Incagli, M Incandela, J Introzzi, G Iwai, J Iwata, Y James, E Jensen, H Joshi, U Kajfasz, E Kambara, H Kamon, T Kaneko, T Karr, K Kasha, H Kato, Y Keaffaber, TA Kelley, K Kennedy, RD Kephart, R Kestenbaum, D Khazins, D Kikuchi, T Kim, BJ Kim, HS Kim, SH Kim, YK Kirsch, L Klimenko, S Knoblauch, D Koehn, P Kongeter, A Kondo, K Konigsberg, J Kordas, K Korytov, A Kovacs, E Kowald, W Kroll, J Kruse, M Kuhlmann, SE Kuns, E Kurino, K Kuwabara, T Laasanen, AT Lami, S Lammel, S Lamoureux, JI Lancaster, M Lanzoni, M Latino, G LeCompte, T Leone, S Lewis, JD Lindgren, M Liss, TM Liu, JB Liu, YC Lockyer, N Long, O Loomis, C Loreti, M Lucchesi, D Lukens, P Lusin, S Lys, J Maeshima, K Maksimovic, P Mangano, M Mariotti, M Marriner, JP Martignon, G Martin, A Matthews, JAJ Mazzanti, P McFarland, K McIntyre, P Melese, P Menguzzato, M Menzione, A Meschi, E Metzler, S Miao, C Miao, T Michail, G Miller, R Minato, H Miscetti, S Mishina, M Miyashita, S Moggi, N Moore, E Morita, Y Mukherjee, A Muller, T Murat, P Murgia, S Musy, M Nakada, H Nakaya, T Nakano, I Nelson, C Neuberger, D Newman-Holmes, C Ngan, CYP Nodulman, L Nomerotski, A Oh, SH Ohmoto, T Ohsugi, T Oishi, R Okabe, M Okusawa, T Olsen, J Pagliarone, C Paoletti, R Papadimitriou, V Pappas, SP Parashar, N Parri, A Patrick, J Pauletta, G Paulini, M Perazzo, A Pescara, L Peters, MD Phillips, TJ Piacentino, G Pillai, M Pitts, KT Plunkett, R Pompos, A Pondrom, L Proudfoot, J Ptohos, F Punzi, G Ragan, K Reher, D Reischl, M Ribon, A Rimondi, F Ristori, L Robertson, WJ Rodrigo, T Rolli, S Rosenson, L Roser, R Saab, T Sakumoto, WK Saltzberg, D Sansoni, A Santi, L Sato, H Schlabach, P Schmidt, EE Schmidt, MP Scott, A Scribano, A Segler, S Seidel, S Seiya, Y Semeria, F Shah, T Shapiro, MD Shaw, NM Shepard, PF Shibayama, T Shimojima, M Shochet, M Siegrist, J Sill, A Sinervo, P Singh, P Sliwa, K Smith, C Snider, FD Spalding, J Speer, T Sphicas, P Spinella, F Spiropulu, M Spiegel, L Stanco, L Steele, J Stefanini, A Strohmer, R Strologas, J Strumia, F Stuart, D Sumorok, K Suzuki, J Suzuki, T Takahashi, T Takano, T Takashima, R Takikawa, K Tanaka, M Tannenbaum, B Tartarelli, F Taylor, W Tecchio, M Teng, PK Teramoto, Y Terashi, K Tether, S Theriot, D Thomas, TL Thurman-Keup, R Timko, M Tipton, P Titov, A Tkaczyk, S Toback, D Tollefson, K Tollestrup, A Toyoda, H Trischuk, W de Troconiz, JF Truitt, S Tseng, J Turini, N Uchida, T Ukegawa, F Valls, J van den Brink, SC Vejcik, S Velev, G Vidal, R Vilar, R Vucinic, D Wagner, RG Wagner, RL Wahl, J Wallace, NB Walsh, AM Wang, C Wang, CH Wang, MJ Warburton, A Watanabe, T Watts, T Webb, R Wei, C Wenzel, H Wester, WC Wicklund, AB Wicklund, E Wilkinson, R Williams, HH Wilson, P Winer, BL Winn, D Wolinski, D Wolinski, J Worm, S Wu, X Wyss, J Yagil, A Yao, W Yasuoka, K Yeh, GP Yeh, P Yoh, J Yosef, C Yoshida, T Yu, I Zanetti, A Zetti, F Zucchelli, S AF Abe, F Akimoto, H Akopian, A Albrow, MG Amadon, A Amendolia, SR Amidei, D Antos, J Aota, S Apollinari, G Arisawa, T Asakawa, T Ashmanskas, W Atac, M Azzi-Bacchetta, P Bacchetta, N Bagdasarov, S Bailey, MW de Barbaro, P Barbaro-Galtieri, A Barnes, VE Barnett, BA Barone, M Bauer, G Baumann, T Bedeschi, F Behrends, S Belforte, S Bellettini, G Bellinger, J Benjamin, D Bensinger, J Beretvas, A Berge, JP Berryhill, J Bertolucci, S Bettelli, S Bevensee, B Bhatti, A Biery, K Bigongiari, C Binkley, M Bisello, D Blair, RE Blocker, C Bloom, K Busk, S Bodek, A Bokhari, W Bolla, G Bonushkin, Y Bortoletto, D Boudreau, J Breccia, L Bromberg, C Bruner, N Brunetti, R Buckley-Geer, E Budd, HS Burkett, K Busetto, G Byon-Wagner, A Byrum, KL Campbell, M Caner, A Carithers, W Carlsmith, D Cassada, J Castro, A Cauz, D Cerri, A Chang, PS Chang, PT Chao, HY Chapman, J Cheng, MT Chertok, M Chiarelli, G Chiou, CN Chlebana, F Christofek, L Chu, ML Cihangir, S Clark, AG Cobal, M Cocca, E Contreras, M Conway, J Cooper, J Cordelli, M Costanzo, D Couyoumtzelis, C Cronin-Hennessy, D Culbertson, R Dagenhart, D Daniels, T DeJongh, F Dell'Agnello, S Dell'Orso, M Demina, R Demortier, L Deninno, M Derwent, PF Devlin, T Dittmann, JR Donati, S Done, J Dorigo, T Eddy, N Einsweiler, K Elias, JE Ely, R Engels, E Erdmann, W Errede, D Errede, S Fan, Q Feild, RG Feng, Z Ferretti, C Fiori, I Flaugher, B Foster, GW Franklin, M Freeman, J Friedman, J Frisch, H Fukui, Y Gadomski, S Galeotti, S Gallinaro, M Ganel, O Garcia-Sciveres, M Garfinkel, AF Gay, C Geer, S Gerdes, DW Giannetti, P Giokaris, N Giromini, P Giusti, G Gold, M Gordon, A Goshaw, AT Gotra, Y Goulianos, K Grassmann, H Groer, L Grosso-Pilcher, C Guillian, G da Costa, JG Guo, RS Haber, C Hafen, E Hahn, SR Hamilton, R Handa, T Handler, R Happacher, F Hara, K Hardman, AD Harris, RM Hartmann, F Hauser, J Hayashi, E Heinrich, J Hao, W Hinrichsen, B Hoffman, KD Hohlmann, M Holck, C Hollebeek, R Holloway, L Huang, Z Huffman, BT Hughes, R Huston, J Huth, J Ikeda, H Incagli, M Incandela, J Introzzi, G Iwai, J Iwata, Y James, E Jensen, H Joshi, U Kajfasz, E Kambara, H Kamon, T Kaneko, T Karr, K Kasha, H Kato, Y Keaffaber, TA Kelley, K Kennedy, RD Kephart, R Kestenbaum, D Khazins, D Kikuchi, T Kim, BJ Kim, HS Kim, SH Kim, YK Kirsch, L Klimenko, S Knoblauch, D Koehn, P Kongeter, A Kondo, K Konigsberg, J Kordas, K Korytov, A Kovacs, E Kowald, W Kroll, J Kruse, M Kuhlmann, SE Kuns, E Kurino, K Kuwabara, T Laasanen, AT Lami, S Lammel, S Lamoureux, JI Lancaster, M Lanzoni, M Latino, G LeCompte, T Leone, S Lewis, JD Lindgren, M Liss, TM Liu, JB Liu, YC Lockyer, N Long, O Loomis, C Loreti, M Lucchesi, D Lukens, P Lusin, S Lys, J Maeshima, K Maksimovic, P Mangano, M Mariotti, M Marriner, JP Martignon, G Martin, A Matthews, JAJ Mazzanti, P McFarland, K McIntyre, P Melese, P Menguzzato, M Menzione, A Meschi, E Metzler, S Miao, C Miao, T Michail, G Miller, R Minato, H Miscetti, S Mishina, M Miyashita, S Moggi, N Moore, E Morita, Y Mukherjee, A Muller, T Murat, P Murgia, S Musy, M Nakada, H Nakaya, T Nakano, I Nelson, C Neuberger, D Newman-Holmes, C Ngan, CYP Nodulman, L Nomerotski, A Oh, SH Ohmoto, T Ohsugi, T Oishi, R Okabe, M Okusawa, T Olsen, J Pagliarone, C Paoletti, R Papadimitriou, V Pappas, SP Parashar, N Parri, A Patrick, J Pauletta, G Paulini, M Perazzo, A Pescara, L Peters, MD Phillips, TJ Piacentino, G Pillai, M Pitts, KT Plunkett, R Pompos, A Pondrom, L Proudfoot, J Ptohos, F Punzi, G Ragan, K Reher, D Reischl, M Ribon, A Rimondi, F Ristori, L Robertson, WJ Rodrigo, T Rolli, S Rosenson, L Roser, R Saab, T Sakumoto, WK Saltzberg, D Sansoni, A Santi, L Sato, H Schlabach, P Schmidt, EE Schmidt, MP Scott, A Scribano, A Segler, S Seidel, S Seiya, Y Semeria, F Shah, T Shapiro, MD Shaw, NM Shepard, PF Shibayama, T Shimojima, M Shochet, M Siegrist, J Sill, A Sinervo, P Singh, P Sliwa, K Smith, C Snider, FD Spalding, J Speer, T Sphicas, P Spinella, F Spiropulu, M Spiegel, L Stanco, L Steele, J Stefanini, A Strohmer, R Strologas, J Strumia, F Stuart, D Sumorok, K Suzuki, J Suzuki, T Takahashi, T Takano, T Takashima, R Takikawa, K Tanaka, M Tannenbaum, B Tartarelli, F Taylor, W Tecchio, M Teng, PK Teramoto, Y Terashi, K Tether, S Theriot, D Thomas, TL Thurman-Keup, R Timko, M Tipton, P Titov, A Tkaczyk, S Toback, D Tollefson, K Tollestrup, A Toyoda, H Trischuk, W de Troconiz, JF Truitt, S Tseng, J Turini, N Uchida, T Ukegawa, F Valls, J van den Brink, SC Vejcik, S Velev, G Vidal, R Vilar, R Vucinic, D Wagner, RG Wagner, RL Wahl, J Wallace, NB Walsh, AM Wang, C Wang, CH Wang, MJ Warburton, A Watanabe, T Watts, T Webb, R Wei, C Wenzel, H Wester, WC Wicklund, AB Wicklund, E Wilkinson, R Williams, HH Wilson, P Winer, BL Winn, D Wolinski, D Wolinski, J Worm, S Wu, X Wyss, J Yagil, A Yao, W Yasuoka, K Yeh, GP Yeh, P Yoh, J Yosef, C Yoshida, T Yu, I Zanetti, A Zetti, F Zucchelli, S CA CDF Collaboration TI Search for Higgs bosons produced in association with a vector boson in p(p)over-bar collisions at root s=1.8 TeV SO PHYSICAL REVIEW LETTERS LA English DT Article ID FERMILAB-TEVATRON; COLLIDER DETECTOR; PARTICLES; PHYSICS AB We search for Higgs bosons produced in association with a massive vector boson in 91 +/- 7 pb(-1) of p(p)over-bar collisions at root s = 1.8 TeV recorded by the Collider Detector at Fermilab. We assume the Higgs scalar H(0) decays to a b(b)over-bar pair with branching ratio beta, and we consider the hadronic decays of the vector boson V(W or Z). Observations are consistent with background expectations. We place 95% confidence level upper limits on sigma(p(p)-over-bar --> H(0)V)beta as a function of the scalar mass (M(H0)) over the range 70 less-than M(H0) less-than 140 GeV/c(2). When combined with an analysis of the case where V is a leptonically decaying W, these limits vary from 23 ph at M(H0) = 70 GeV/c(2) to 17 pb at M(H0) = 140 GeV/c(2). C1 Kek Nat Lab High Energy Phys, Tsukuba, Ibaraki 305, Japan. Argonne Natl Lab, Argonne, IL 60439 USA. Univ Bologna, Ist Nazl Fis Nucl, I-40127 Bologna, Italy. Brandeis Univ, Waltham, MA 02254 USA. Univ Calif Los Angeles, Los Angeles, CA 90024 USA. Univ Chicago, Chicago, IL 60637 USA. Duke Univ, Durham, NC 27708 USA. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Florida, Gainesville, FL 32611 USA. Ist Nazl Fis Nucl, Lab Nazl Frascati, I-00044 Frascati, Italy. Univ Geneva, CH-1211 Geneva 4, Switzerland. Harvard Univ, Cambridge, MA 02138 USA. Hiroshima Univ, Higashihiroshima 724, Japan. Univ Illinois, Urbana, IL 61801 USA. McGill Univ, Inst Particle Phys, Montreal, PQ H3A 2T8, Canada. Univ Toronto, Toronto, ON M5S 1A7, Canada. Johns Hopkins Univ, Baltimore, MD 21218 USA. Univ Karlsruhe, Inst Expt Kernphys, D-76128 Karlsruhe, Germany. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. MIT, Cambridge, MA 02139 USA. Univ Michigan, Ann Arbor, MI 48109 USA. Michigan State Univ, E Lansing, MI 48824 USA. Univ New Mexico, Albuquerque, NM 87131 USA. Ohio State Univ, Columbus, OH 43210 USA. Osaka City Univ, Osaka 588, Japan. Univ Padua, Ist Nazl Fis Nucl, Sez Padova, I-35131 Padua, Italy. Univ Penn, Philadelphia, PA 19104 USA. Univ Pisa, Ist Nazl Fis Nucl, I-56100 Pisa, Italy. Scuola Normale Super Pisa, I-56100 Pisa, Italy. Univ Pittsburgh, Pittsburgh, PA 15260 USA. Purdue Univ, W Lafayette, IN 47907 USA. Univ Rochester, Rochester, NY 14627 USA. Rockefeller Univ, New York, NY 10021 USA. Rutgers State Univ, Piscataway, NJ 08855 USA. Acad Sinica, Taipei 11530, Taiwan. Texas A&M Univ, College Stn, TX 77843 USA. Texas Tech Univ, Lubbock, TX 79409 USA. Univ Trieste, Ist Nazl Fis Nucl, Udine, Italy. Univ Tsukuba, Tokyo, Ibaraki 315, Japan. Tufts Univ, Medford, MA 02155 USA. Waseda Univ, Tokyo 169, Japan. Univ Wisconsin, Madison, WI USA. Yale Univ, New Haven, CT 06520 USA. RP Abe, F (reprint author), Kek Nat Lab High Energy Phys, Tsukuba, Ibaraki 305, Japan. RI Lancaster, Mark/C-1693-2008; Vucinic, Dejan/C-2406-2008; Peters, Michael/B-4973-2009; Nomerotski, Andrei/A-5169-2010; Azzi, Patrizia/H-5404-2012; Punzi, Giovanni/J-4947-2012; Chiarelli, Giorgio/E-8953-2012; Warburton, Andreas/N-8028-2013; Paulini, Manfred/N-7794-2014; Introzzi, Gianluca/K-2497-2015; vilar, rocio/D-7454-2014 OI Azzi, Patrizia/0000-0002-3129-828X; Punzi, Giovanni/0000-0002-8346-9052; Chiarelli, Giorgio/0000-0001-9851-4816; Warburton, Andreas/0000-0002-2298-7315; Paulini, Manfred/0000-0002-6714-5787; Introzzi, Gianluca/0000-0002-1314-2580; NR 22 TC 26 Z9 26 U1 0 U2 3 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD DEC 28 PY 1998 VL 81 IS 26 BP 5748 EP 5753 DI 10.1103/PhysRevLett.81.5748 PG 6 WC Physics, Multidisciplinary SC Physics GA 152DG UT WOS:000077760200011 ER PT J AU Abe, F Akimoto, H Akopian, A Albrow, MG Amadon, A Amendolia, SR Amidei, D Antos, J Aota, S Apollinari, G Arisawa, T Asakawa, T Ashmanskas, W Atac, M Azzi-Bacchetta, P Bacchetta, N Bagdasarov, S Bailey, MW de Barbaro, P Barbaro-Galtieri, A Barnes, VE Barnett, BA Barone, M Bauer, G Baumann, T Bedeschi, F Behrends, S Belforte, S Bellettini, G Bellinger, J Benjamin, D Bensinger, J Beretvas, A Berge, JP Berryhill, J Bertolucci, S Bettelli, S Bevensee, B Bhatti, A Biery, K Bigongiari, C Binkley, M Bisello, D Blair, RE Blocker, C Blusk, S Bodek, A Bokhari, W Bolla, G Bonushkin, Y Bortoletto, D Boudreau, J Breccia, L Bromberg, C Bruner, N Brunetti, R Buckley-Geer, E Budd, HS Burkett, K Busetto, G Byon-Wagner, A Byrum, KL Campbell, M Caner, A Carithers, W Carlsmith, D Cassada, J Castro, A Cauz, D Cerri, A Chang, PS Chang, PT Chao, HY Chapman, J Cheng, MT Chertok, M Chiarelli, G Chiou, CN Chlebana, F Christofek, L Chu, ML Cihangir, S Clark, AG Cobal, M Cocca, E Contreras, M Conway, J Cooper, J Cordelli, M Costanzo, D Couyoumtzelis, C Cronin-Hennessy, D Culbertson, R Dagenhart, D Daniels, T Dell'Agnello, DS Dell'Orso, M Demina, R Demortier, L Deninno, M Derwent, PF Devlin, T Dittmann, JR Donati, S Done, J Dorigo, T Eddy, N Einsweiler, K Elias, JE Ely, R Engels, E Erdmann, W Errede, D Errede, S Fan, Q Feild, RG Feng, Z Ferretti, C Fiori, I Flaugher, B Foster, GW Franklin, M Freeman, J Friedman, J Frisch, H Fukui, Y Gadomski, S Galeotti, S Gallinaro, M Ganel, O Garcia-Sciveres, M Garfinkel, AF Gay, C Geer, S Gerdes, DW Giannetti, P Giokaris, N Giromini, P Giusti, G Gold, M Gordon, A Goshaw, AT Gotra, Y Goulianos, K Grassmann, H Groer, L Grosso-Pilcher, C Guillian, G da Costa, JG Guo, R Haber, C Hafen, E Hahn, SR Hamilton, R Handa, T Handler, R Happacher, F Hara, K Hardman, AD Harris, RM Hartmann, F Hauser, J Hayashi, E Heinrich, J Hao, W Hinrichsen, B Hoffman, KD Hohlmann, M Holck, C Hollebeek, R Holloway, L Huang, Z Huffman, BT Hughes, R Huston, J Huth, J Ikeda, H Incagli, M Incandela, J Introzzi, G Iwai, J Iwata, Y James, E Jensen, H Joshi, U Kajfasz, E Kambara, H Kamon, T Kaneko, T Karr, K Kasha, H Kato, Y Keaffaber, TA Kelley, K Kennedy, RD Kephart, R Kestenbaum, D Khazins, D Kikuchi, T Kim, BJ Kim, HS Kim, SH Kim, YK Kirsch, L Klimenko, S Knoblauch, D Koehn, P Kongeter, A Kondo, K Konigsberg, J Kordas, K Korytov, A Kovacs, E Kowald, W Kroll, J Kruse, M Kuhlmann, SE Kuns, E Kurino, K Kuwabara, T Laasanen, AT Lami, S Lammel, S Lamoureux, JI Lancaster, M Lanzoni, M Latino, G LeCompte, T Leone, S Lewis, JD Limon, P Lindgren, M Liss, TM Liu, JB Liu, YC Lockyer, N Long, O Loomis, C Loreti, M Lucchesi, D Lukens, P Lusin, S Lys, J Maeshima, K Maksimovic, P Mangano, M Mariotti, M Marriner, JP Martin, A Matthews, JAJ Mazzanti, P McIntyre, P Melese, P Menguzzato, M Menzione, A Meschi, E Metzler, S Miao, C Miao, T Michail, G Miller, R Minato, H Miscetti, S Mishina, M Miyashita, S Moggi, N Moore, E Morita, Y Mukherjee, A Muller, T Murat, P Murgia, S Nakada, H Nakano, I Nelson, C Neuberger, D Newman-Holmes, C Ngan, CYP Nodulman, L Nomerotski, A Oh, SH Ohmoto, T Ohsugi, T Oishi, R Okabe, M Okusawa, T Olsen, J Pagliarone, C Paoletti, R Papadimitriou, V Pappas, SP Parashar, N Parri, A Patrick, J Pauletta, G Paulini, M Perazzo, A Pescara, L Peters, MD Phillips, TJ Piacentino, G Pillai, M Pitts, KT Plunkett, R Pompos, A Pondrom, L Proudfoot, J Ptohos, F Punzi, G Ragan, K Reher, D Reischl, M Ribon, A Rimondi, F Ristori, L Robertson, WJ Rodrigo, T Rolli, S Rosenson, L Roser, R Saab, T Sakumoto, WK Saltzberg, D Sansoni, A Santi, L Sato, H Schlabach, P Schmidt, EE Schmidt, MP Scott, A Scribano, A Segler, S Seidel, S Seiya, Y Semeria, F Shah, T Shapiro, MD Shaw, NM Shepard, PF Shibayama, T Shimojima, M Shochet, M Siegrist, J Sill, A Sinervo, P Singh, P Sliwa, K Smith, C Snider, FD Spalding, J Speer, T Sphicas, P Spinella, F Spiropulu, M Spiegel, L Stanco, L Steele, J Stefanini, A Strohmer, R Strologas, J Strumia, F Stuart, D Sumorok, K Suzuki, J Suzuki, T Takahashi, T Takano, T Takashima, R Takikawa, K Tanaka, M Tannenbaum, B Tartarelli, F Taylor, W Tecchio, M Teng, PK Teramoto, Y Terashi, K Tether, S Theriot, D Thomas, TL Thurman-Keup, R Timko, M Tipton, P Titov, A Tkaczyk, S Toback, D Tollefson, K Tollestrup, A Toyoda, H Trischuk, W de Troconiz, JF Truitt, S Tseng, J Turini, N Uchida, T Ukegawa, F Valls, J van den Brink, SC Vejcik, S Velev, G Vidal, R Vilar, R Vucinic, D Wagner, RG Wagner, RL Wahl, J Wallace, NB Walsh, AM Wang, C Wang, CH Wang, MJ Warburton, A Watanabe, T Watts, T Webb, R Wei, C Wenzel, H Wester, WC Wicklund, AB Wicklund, E Wilkinson, R Williams, HH Wilson, P Winer, BL Winn, D Wolinski, D Wolinski, J Worm, S Wu, X Wyss, J Yagil, A Yao, W Yasuoka, K Yeh, GP Yeh, P Yoh, J Yosef, C Yoshida, T Yu, I Zanetti, A Zetti, F Zucchelli, S AF Abe, F Akimoto, H Akopian, A Albrow, MG Amadon, A Amendolia, SR Amidei, D Antos, J Aota, S Apollinari, G Arisawa, T Asakawa, T Ashmanskas, W Atac, M Azzi-Bacchetta, P Bacchetta, N Bagdasarov, S Bailey, MW de Barbaro, P Barbaro-Galtieri, A Barnes, VE Barnett, BA Barone, M Bauer, G Baumann, T Bedeschi, F Behrends, S Belforte, S Bellettini, G Bellinger, J Benjamin, D Bensinger, J Beretvas, A Berge, JP Berryhill, J Bertolucci, S Bettelli, S Bevensee, B Bhatti, A Biery, K Bigongiari, C Binkley, M Bisello, D Blair, RE Blocker, C Blusk, S Bodek, A Bokhari, W Bolla, G Bonushkin, Y Bortoletto, D Boudreau, J Breccia, L Bromberg, C Bruner, N Brunetti, R Buckley-Geer, E Budd, HS Burkett, K Busetto, G Byon-Wagner, A Byrum, KL Campbell, M Caner, A Carithers, W Carlsmith, D Cassada, J Castro, A Cauz, D Cerri, A Chang, PS Chang, PT Chao, HY Chapman, J Cheng, MT Chertok, M Chiarelli, G Chiou, CN Chlebana, F Christofek, L Chu, ML Cihangir, S Clark, AG Cobal, M Cocca, E Contreras, M Conway, J Cooper, J Cordelli, M Costanzo, D Couyoumtzelis, C Cronin-Hennessy, D Culbertson, R Dagenhart, D Daniels, T Dell'Agnello, DS Dell'Orso, M Demina, R Demortier, L Deninno, M Derwent, PF Devlin, T Dittmann, JR Donati, S Done, J Dorigo, T Eddy, N Einsweiler, K Elias, JE Ely, R Engels, E Erdmann, W Errede, D Errede, S Fan, Q Feild, RG Feng, Z Ferretti, C Fiori, I Flaugher, B Foster, GW Franklin, M Freeman, J Friedman, J Frisch, H Fukui, Y Gadomski, S Galeotti, S Gallinaro, M Ganel, O Garcia-Sciveres, M Garfinkel, AF Gay, C Geer, S Gerdes, DW Giannetti, P Giokaris, N Giromini, P Giusti, G Gold, M Gordon, A Goshaw, AT Gotra, Y Goulianos, K Grassmann, H Groer, L Grosso-Pilcher, C Guillian, G da Costa, JG Guo, R Haber, C Hafen, E Hahn, SR Hamilton, R Handa, T Handler, R Happacher, F Hara, K Hardman, AD Harris, RM Hartmann, F Hauser, J Hayashi, E Heinrich, J Hao, W Hinrichsen, B Hoffman, KD Hohlmann, M Holck, C Hollebeek, R Holloway, L Huang, Z Huffman, BT Hughes, R Huston, J Huth, J Ikeda, H Incagli, M Incandela, J Introzzi, G Iwai, J Iwata, Y James, E Jensen, H Joshi, U Kajfasz, E Kambara, H Kamon, T Kaneko, T Karr, K Kasha, H Kato, Y Keaffaber, TA Kelley, K Kennedy, RD Kephart, R Kestenbaum, D Khazins, D Kikuchi, T Kim, BJ Kim, HS Kim, SH Kim, YK Kirsch, L Klimenko, S Knoblauch, D Koehn, P Kongeter, A Kondo, K Konigsberg, J Kordas, K Korytov, A Kovacs, E Kowald, W Kroll, J Kruse, M Kuhlmann, SE Kuns, E Kurino, K Kuwabara, T Laasanen, AT Lami, S Lammel, S Lamoureux, JI Lancaster, M Lanzoni, M Latino, G LeCompte, T Leone, S Lewis, JD Limon, P Lindgren, M Liss, TM Liu, JB Liu, YC Lockyer, N Long, O Loomis, C Loreti, M Lucchesi, D Lukens, P Lusin, S Lys, J Maeshima, K Maksimovic, P Mangano, M Mariotti, M Marriner, JP Martin, A Matthews, JAJ Mazzanti, P McIntyre, P Melese, P Menguzzato, M Menzione, A Meschi, E Metzler, S Miao, C Miao, T Michail, G Miller, R Minato, H Miscetti, S Mishina, M Miyashita, S Moggi, N Moore, E Morita, Y Mukherjee, A Muller, T Murat, P Murgia, S Nakada, H Nakano, I Nelson, C Neuberger, D Newman-Holmes, C Ngan, CYP Nodulman, L Nomerotski, A Oh, SH Ohmoto, T Ohsugi, T Oishi, R Okabe, M Okusawa, T Olsen, J Pagliarone, C Paoletti, R Papadimitriou, V Pappas, SP Parashar, N Parri, A Patrick, J Pauletta, G Paulini, M Perazzo, A Pescara, L Peters, MD Phillips, TJ Piacentino, G Pillai, M Pitts, KT Plunkett, R Pompos, A Pondrom, L Proudfoot, J Ptohos, F Punzi, G Ragan, K Reher, D Reischl, M Ribon, A Rimondi, F Ristori, L Robertson, WJ Rodrigo, T Rolli, S Rosenson, L Roser, R Saab, T Sakumoto, WK Saltzberg, D Sansoni, A Santi, L Sato, H Schlabach, P Schmidt, EE Schmidt, MP Scott, A Scribano, A Segler, S Seidel, S Seiya, Y Semeria, F Shah, T Shapiro, MD Shaw, NM Shepard, PF Shibayama, T Shimojima, M Shochet, M Siegrist, J Sill, A Sinervo, P Singh, P Sliwa, K Smith, C Snider, FD Spalding, J Speer, T Sphicas, P Spinella, F Spiropulu, M Spiegel, L Stanco, L Steele, J Stefanini, A Strohmer, R Strologas, J Strumia, F Stuart, D Sumorok, K Suzuki, J Suzuki, T Takahashi, T Takano, T Takashima, R Takikawa, K Tanaka, M Tannenbaum, B Tartarelli, F Taylor, W Tecchio, M Teng, PK Teramoto, Y Terashi, K Tether, S Theriot, D Thomas, TL Thurman-Keup, R Timko, M Tipton, P Titov, A Tkaczyk, S Toback, D Tollefson, K Tollestrup, A Toyoda, H Trischuk, W de Troconiz, JF Truitt, S Tseng, J Turini, N Uchida, T Ukegawa, F Valls, J van den Brink, SC Vejcik, S Velev, G Vidal, R Vilar, R Vucinic, D Wagner, RG Wagner, RL Wahl, J Wallace, NB Walsh, AM Wang, C Wang, CH Wang, MJ Warburton, A Watanabe, T Watts, T Webb, R Wei, C Wenzel, H Wester, WC Wicklund, AB Wicklund, E Wilkinson, R Williams, HH Wilson, P Winer, BL Winn, D Wolinski, D Wolinski, J Worm, S Wu, X Wyss, J Yagil, A Yao, W Yasuoka, K Yeh, GP Yeh, P Yoh, J Yosef, C Yoshida, T Yu, I Zanetti, A Zetti, F Zucchelli, S CA CDF Collaboration TI Measurement of the lepton charge asymmetry in W-boson decays produced in p(p)over-bar collisions SO PHYSICAL REVIEW LETTERS LA English DT Article ID PARTON DISTRIBUTIONS; HADRON COLLIDERS AB We describe a measurement of the charge asymmetry of leptons from W-boson decays in the rapidity range 0 less-than [y(iota)] < 2.5 using W --> e nu, mu nu events from 110 +/- 7 pb(-1) of data collected by the CDF detector during 1992-1995. The asymmetry data constrain the ratio of d and u quark momentum distributions in the proton over the x range of 0.006 to 0.34 at Q(2) = M(W)(2). The asymmetry predictions that use parton distribution functions obtained from previously published CDF data in the central rapidity region (0.0 less-than [y(iota)] less-than 1.1) do not agree with the new data in the large rapidity region ([y(iota)] greater-than 1.1). C1 Kek Nat Lab High Energy Phys, Tsukuba, Ibaraki 305, Japan. Argonne Natl Lab, Argonne, IL 60439 USA. Univ Bologna, Ist Nazl Fis Nucl, I-40127 Bologna, Italy. Brandeis Univ, Waltham, MA 02254 USA. Univ Calif Los Angeles, Los Angeles, CA 90024 USA. Univ Chicago, Chicago, IL 60637 USA. Duke Univ, Durham, NC 27708 USA. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Florida, Gainesville, FL 32611 USA. Ist Nazl Fis Nucl, Lab Nazl Frascati, I-00044 Frascati, Italy. Univ Geneva, CH-1211 Geneva 4, Switzerland. Harvard Univ, Cambridge, MA 02138 USA. Hiroshima Univ, Higashihiroshima 724, Japan. Univ Illinois, Urbana, IL 61801 USA. McGill Univ, Inst Particle Phys, Montreal, PQ H3A 2T8, Canada. Univ Toronto, Toronto, ON M5S 1A7, Canada. Johns Hopkins Univ, Baltimore, MD 21218 USA. Univ Karlsruhe, Inst Expt Kernphys, D-76128 Karlsruhe, Germany. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. MIT, Cambridge, MA 02139 USA. Univ Michigan, Ann Arbor, MI 48109 USA. Michigan State Univ, E Lansing, MI 48824 USA. Univ New Mexico, Albuquerque, NM 87131 USA. Ohio State Univ, Columbus, OH 43210 USA. Osaka City Univ, Osaka 588, Japan. Univ Padua, Ist Nazl Fis Nucl, Sez Padova, I-35131 Padua, Italy. Univ Penn, Philadelphia, PA 19104 USA. Univ Pisa, Ist Nazl Fis Nucl, I-56100 Pisa, Italy. Scuola Normale Super Pisa, I-56100 Pisa, Italy. Univ Pittsburgh, Pittsburgh, PA 15260 USA. Purdue Univ, W Lafayette, IN 47907 USA. Univ Rochester, Rochester, NY 14627 USA. Rockefeller Univ, New York, NY 10021 USA. Rutgers State Univ, Piscataway, NJ 08855 USA. Acad Sinica, Taipei 11530, Taiwan. Texas A&M Univ, College Stn, TX 77843 USA. Texas Tech Univ, Lubbock, TX 79409 USA. Univ Trieste, Ist Nazl Fis Nucl, Udine, Italy. Univ Tsukuba, Tokyo, Ibaraki 315, Japan. Tufts Univ, Medford, MA 02155 USA. Waseda Univ, Tokyo 169, Japan. Univ Wisconsin, Madison, WI 53706 USA. Yale Univ, New Haven, CT 06520 USA. RP Abe, F (reprint author), Kek Nat Lab High Energy Phys, Tsukuba, Ibaraki 305, Japan. RI Lancaster, Mark/C-1693-2008; Vucinic, Dejan/C-2406-2008; Nomerotski, Andrei/A-5169-2010; Azzi, Patrizia/H-5404-2012; Punzi, Giovanni/J-4947-2012; Chiarelli, Giorgio/E-8953-2012; Warburton, Andreas/N-8028-2013; Paulini, Manfred/N-7794-2014; Introzzi, Gianluca/K-2497-2015; vilar, rocio/D-7454-2014; OI Turini, Nicola/0000-0002-9395-5230; Azzi, Patrizia/0000-0002-3129-828X; Punzi, Giovanni/0000-0002-8346-9052; Chiarelli, Giorgio/0000-0001-9851-4816; Warburton, Andreas/0000-0002-2298-7315; Paulini, Manfred/0000-0002-6714-5787; Introzzi, Gianluca/0000-0002-1314-2580; Meschi, Emilio/0000-0003-4502-6151; Gallinaro, Michele/0000-0003-1261-2277 NR 21 TC 64 Z9 64 U1 0 U2 3 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD DEC 28 PY 1998 VL 81 IS 26 BP 5754 EP 5759 DI 10.1103/PhysRevLett.81.5754 PG 6 WC Physics, Multidisciplinary SC Physics GA 152DG UT WOS:000077760200012 ER PT J AU Adams, GS Adams, T Bar-Yam, Z Bishop, JM Bodyagin, VA Brabson, BB Brown, DS Cason, NM Chung, SU Crittenden, RR Cummings, JP Danyo, K Denisov, S Dorofeev, V Dowd, JP Dzierba, AR Eugenio, P Gunter, J Hackenburg, RW Hayek, M Ivanov, EI Kachaev, I Kern, W King, E Kodolova, OL Korotkikh, VL Kostin, MA Kuhn, J Lindenbusch, R Lipaev, V LoSecco, JM Manak, JJ Napolitano, J Nozar, M Olchanski, C Ostrovidov, AI Pedlar, TK Popov, A Rust, DR Ryabchikov, D Sanjari, AH Sarycheva, LI Scott, E Seth, KK Shenhav, N Shephard, WD Sinev, NB Smith, JA Smith, PT Stienike, DL Sulanke, T Taegar, SA Teige, S Thompson, DR Vardanyan, IN Weygand, DP White, D Willutzki, HJ Wise, J Witkowski, M Yershov, AA Zhao, D AF Adams, GS Adams, T Bar-Yam, Z Bishop, JM Bodyagin, VA Brabson, BB Brown, DS Cason, NM Chung, SU Crittenden, RR Cummings, JP Danyo, K Denisov, S Dorofeev, V Dowd, JP Dzierba, AR Eugenio, P Gunter, J Hackenburg, RW Hayek, M Ivanov, EI Kachaev, I Kern, W King, E Kodolova, OL Korotkikh, VL Kostin, MA Kuhn, J Lindenbusch, R Lipaev, V LoSecco, JM Manak, JJ Napolitano, J Nozar, M Olchanski, C Ostrovidov, AI Pedlar, TK Popov, A Rust, DR Ryabchikov, D Sanjari, AH Sarycheva, LI Scott, E Seth, KK Shenhav, N Shephard, WD Sinev, NB Smith, JA Smith, PT Stienike, DL Sulanke, T Taegar, SA Teige, S Thompson, DR Vardanyan, IN Weygand, DP White, D Willutzki, HJ Wise, J Witkowski, M Yershov, AA Zhao, D CA E852 Collaboration TI Observation of a new J(PC)=1(-+) exotic state in the reaction pi(-)p ->pi(+)pi(-)pi(-)p at 18 GeV/c SO PHYSICAL REVIEW LETTERS LA English DT Article ID FLUX-TUBE MODEL; HYBRID MESONS; QCD; SYSTEM; MATRIX; DECAY AB A partial-wave analysis of the reaction pi(-)p --> pi(+)pi(-)pi(-)p at 18 GeV/c has been performed on a data sample of 250 000 events obtained by Brookhaven experiment E852. The expected J(PC) = l(++)a(1)(1260), 2(++)a(2)(1320), and 2(-+)pi(2)(1670) resonant states are clearly observed. The exotic J(PC) = 1(-+) wave produced in the natural parity exchange processes shows distinct resonancelike phase motion at about 1.6 GeV/c(2) in the rho pi channel. A mass-dependent fit results in a resonance mass of 1593 +/- 8(-47)(+29) MeV/c(2) and a width of 168 +/- 20(-12)(+150) MeV/c(2). C1 Rensselaer Polytech Inst, Dept Phys, Troy, NY 12180 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. Moscow MV Lomonosov State Univ, Inst Nucl Phys, Moscow 119899, Russia. Univ Massachusetts, Dept Phys, N Dartmouth, MA 02747 USA. Univ Notre Dame, Dept Phys, Notre Dame, IN 46556 USA. Indiana Univ, Dept Phys, Bloomington, IN 47405 USA. Northwestern Univ, Dept Phys, Evanston, IL 60208 USA. Protvino High Energy Phys Inst, Protvino 142284, Russia. RAFAEL, IL-31021 Haifa, Israel. RP Adams, GS (reprint author), Rensselaer Polytech Inst, Dept Phys, Troy, NY 12180 USA. RI Vardanyan, Irina/K-7981-2012 NR 28 TC 192 Z9 195 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD DEC 28 PY 1998 VL 81 IS 26 BP 5760 EP 5763 DI 10.1103/PhysRevLett.81.5760 PG 4 WC Physics, Multidisciplinary SC Physics GA 152DG UT WOS:000077760200013 ER PT J AU van Hecke, H Sorge, H Xu, N AF van Hecke, H Sorge, H Xu, N TI Evidence of early multistrange hadron freeze-out in high energy nuclear collisions SO PHYSICAL REVIEW LETTERS LA English DT Article ID HEAVY-ION COLLISIONS; PHASE-TRANSITION; PB COLLISIONS; EXPANSION; MATTER; EQUILIBRATION; PARAMETERS; ACS; SPS; QCD AB Recently reported transverse momentum distributions of strange hadrons produced in Pb(158A GeV) on Pb collisions and corresponding results from the relativistic quantum molecular dynamics approach are examined. We argue that the experimental observations favor a scenario in which multistrange hadrons are formed and decouple from the system rather early at large energy densities (at about 1 GeV/fm(3)). The systematics of the strange and nonstrange particle spectra indicate that the observed transverse flow develops mainly in the late hadronic stages of these reactions. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. SUNY Stony Brook, Dept Phys, Stony Brook, NY 11794 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. RP van Hecke, H (reprint author), Univ Calif Los Alamos Natl Lab, MS H846, Los Alamos, NM 87545 USA. NR 34 TC 166 Z9 166 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD DEC 28 PY 1998 VL 81 IS 26 BP 5764 EP 5767 DI 10.1103/PhysRevLett.81.5764 PG 4 WC Physics, Multidisciplinary SC Physics GA 152DG UT WOS:000077760200014 ER PT J AU Dorner, R Brauning, H Jagutzki, O Mergel, V Achler, M Moshammer, R Feagin, JM Osipov, F Brauning-Demian, A Spielberger, L McGuire, JH Prior, MH Berrah, N Bozek, JD Cocke, CL Schmidt-Bocking, H AF Dorner, R Brauning, H Jagutzki, O Mergel, V Achler, M Moshammer, R Feagin, JM Osipov, F Brauning-Demian, A Spielberger, L McGuire, JH Prior, MH Berrah, N Bozek, JD Cocke, CL Schmidt-Bocking, H TI Double photoionization of spatially aligned D-2 SO PHYSICAL REVIEW LETTERS LA English DT Article ID PHOTOELECTRON ANGULAR-DISTRIBUTIONS; RECOIL-ION; DOUBLE-IONIZATION; SHAPE RESONANCES; MOLECULES; HELIUM; ASYMMETRY; ENERGY; H-2 AB The four-body breakup of spatially aligned D-2 by 58.8 eV photons from the Advanced Light Source has been investigated by measuring the three dimensional momentum vectors of both fragment ions and one of the two electrons in coincidence. Energy and angular correlation between ions and electrons is discussed. We find rotational symmetry of the electron angular distribution around the polarization vector of the light and significant differences between helium and D2 as well as between molecular alignment parallel and perpendicular to the polarization axis. C1 Univ Frankfurt, Inst Kernphys, D-60486 Frankfurt, Germany. Kansas State Univ, Dept Phys, Manhattan, KS 66506 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Calif State Univ Fullerton, Dept Phys, Fullerton, CA 94720 USA. Western Michigan Univ, Dept Phys, Kalamazoo, MI 49008 USA. RP Dorner, R (reprint author), Univ Frankfurt, Inst Kernphys, August Euler Str 6, D-60486 Frankfurt, Germany. RI Bozek, John/E-4689-2010; Doerner, Reinhard/A-5340-2008; Bozek, John/E-9260-2010 OI Doerner, Reinhard/0000-0002-3728-4268; Bozek, John/0000-0001-7486-7238 NR 31 TC 71 Z9 71 U1 0 U2 7 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD DEC 28 PY 1998 VL 81 IS 26 BP 5776 EP 5779 DI 10.1103/PhysRevLett.81.5776 PG 4 WC Physics, Multidisciplinary SC Physics GA 152DG UT WOS:000077760200017 ER PT J AU Budker, D Yashchuk, V Zolotorev, R AF Budker, D Yashchuk, V Zolotorev, R TI Nonlinear magneto-optic effects with ultranarrow widths SO PHYSICAL REVIEW LETTERS LA English DT Article ID FARADAY-ROTATION; SAMARIUM VAPOR; RESONANCE AB Several dispersionlike features in the magnetic field dependence of the nonlinear magneto-optic effect were observed in an experiment performed on rubidium atoms contained in a vapor cell with antirelaxation coating. The narrowest feature has effective resonance width gamma = g mu Delta B-z, = 2 pi x 1.3 Hz, where Delta B-z approximate to 2.8 mu G is the peak-to-peak separation. The observed nontrivial dependence of the magneto-optic effect on transverse magnetic fields is discussed. The results of this work may be applied to low-field magnetometry, to parity and time reversal invariance violation experiments, etc. C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. BP Konstantinov Nucl Phys Inst, Gatchina 188350, Russia. RP Budker, D (reprint author), Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. RI Budker, Dmitry/F-7580-2016 OI Budker, Dmitry/0000-0002-7356-4814 NR 23 TC 182 Z9 185 U1 4 U2 25 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD DEC 28 PY 1998 VL 81 IS 26 BP 5788 EP 5791 DI 10.1103/PhysRevLett.81.5788 PG 4 WC Physics, Multidisciplinary SC Physics GA 152DG UT WOS:000077760200020 ER PT J AU Tremaine, A Rosenzweig, JB Anderson, S Frigola, P Hogan, M Murokh, A Pellegrini, C Nguyen, DC Sheffield, RL AF Tremaine, A Rosenzweig, JB Anderson, S Frigola, P Hogan, M Murokh, A Pellegrini, C Nguyen, DC Sheffield, RL TI Observation of self-amplified spontaneous-emission-induced electron-beam microbunching using coherent transition radiation SO PHYSICAL REVIEW LETTERS LA English DT Article ID LINEAR-ACCELERATOR; PLASMA-WAVES; LASER; LINAC; SLAC; FEL AB We report the measurement of electron-beam microbunching at the exit of a self-amplified spontaneous-emission free-electron laser (SASE FEL), by observation of coherent transition radiation (CTR). The CTR was found to have an angular spectrum much narrower than spontaneous transition radiation and a narrow-band frequency spectrum. The central frequency of the fundamental CTR spectrum is found to differ slightly from that of the SASE, a finding in disagreement with previously invoked CTR theory. The CTR measurement establishes the uniformity of microbunching in the transverse dimension, indicating the SASE FEL operates in a dominant transverse mode. C1 Univ Calif Los Angeles, Dept Phys & Astron, Los Angeles, CA 90095 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Tremaine, A (reprint author), Univ Calif Los Angeles, Dept Phys & Astron, 405 Hilgard Ave, Los Angeles, CA 90095 USA. NR 22 TC 54 Z9 57 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD DEC 28 PY 1998 VL 81 IS 26 BP 5816 EP 5819 DI 10.1103/PhysRevLett.81.5816 PG 4 WC Physics, Multidisciplinary SC Physics GA 152DG UT WOS:000077760200027 ER PT J AU Malik, A Sandy, AR Lurio, LB Stephenson, GB Mochrie, SGJ McNulty, I Sutton, M AF Malik, A Sandy, AR Lurio, LB Stephenson, GB Mochrie, SGJ McNulty, I Sutton, M TI Coherent X-ray study of fluctuations during domain coarsening SO PHYSICAL REVIEW LETTERS LA English DT Article ID PHOTON-CORRELATION SPECTROSCOPY; GROWTH; DYNAMICS AB We report observations of the dynamics of the exact structure factor (speckle pattern) during phase separation in a sodium borosilicate glass, measured using intensity fluctuation spectroscopy with a coherent x-ray beam. Nonequilibrium fluctuations in the structure factor are analyzed using a two-time correlation function to extract the time-dependent and wave-number-dependent correlation time. The behavior of the correlation time is in agreement with a scaling law previously found in simulations. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. MIT, Ctr Mat Sci & Engn, Cambridge, MA 02139 USA. Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. McGill Univ, Dept Phys, Montreal, PQ H3A 2T8, Canada. RP Malik, A (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 18 TC 63 Z9 63 U1 2 U2 24 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD DEC 28 PY 1998 VL 81 IS 26 BP 5832 EP 5835 DI 10.1103/PhysRevLett.81.5832 PG 4 WC Physics, Multidisciplinary SC Physics GA 152DG UT WOS:000077760200031 ER PT J AU Lee, GD Wang, CZ Lu, ZY Ho, KM AF Lee, GD Wang, CZ Lu, ZY Ho, KM TI Ad-dimer diffusion between trough and dimer row on Si(100) SO PHYSICAL REVIEW LETTERS LA English DT Article ID SI(001); DYNAMICS; SURFACE; NUCLEATION AB The diffusion pathways between the trough and the dimer row on the Si(100) surface are investigated by tight-binding molecular dynamics calculations using the environment-dependent tight-binding silicon potential and by ab initio calculations using the Car-Parrinello method. The studies discover a new diffusion pathway consisting of the rotation of the ad-dimer. The calculated energy barrier is in excellent agreement with experiment and is much more energetically favorable than other diffusion pathways by parallel and perpendicular ad-dimers. C1 Iowa State Univ, US DOE, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Phys, Ames, IA 50011 USA. RP Lee, GD (reprint author), Iowa State Univ, US DOE, Ames Lab, Ames, IA 50011 USA. RI 上官, 敏慧/E-8964-2012; Lee, Gun-Do/L-1259-2013 OI Lee, Gun-Do/0000-0001-8328-8625 NR 18 TC 36 Z9 37 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD DEC 28 PY 1998 VL 81 IS 26 BP 5872 EP 5875 DI 10.1103/PhysRevLett.81.5872 PG 4 WC Physics, Multidisciplinary SC Physics GA 152DG UT WOS:000077760200041 ER PT J AU Miranda, PB Xu, L Shen, YR Salmeron, M AF Miranda, PB Xu, L Shen, YR Salmeron, M TI Icelike water monolayer adsorbed on mica at room temperature SO PHYSICAL REVIEW LETTERS LA English DT Article ID THIN-FILMS; SURFACE; ICE; ADSORPTION; D2O AB The structure of a water film formed on mica at room temperature, in equilibrium with water vapor at various relative humidities (RH), was studied using sum-frequency-generation (SFG) vibrational spectroscopy and scanning polarization force microscopy (SPFM). Analysis of the O-D stretch modes in the SFG spectra of D2O on mica indicates that as RH increases, the submonolayer water structure evolves into a more ordered hydrogen-bonding network. At full monolayer coverage (similar to 90% RH), the SFG spectrum suggests an icelike film with no dangling O-D groups, in agreement with a recent molecular dynamics simulation. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. RP Miranda, PB (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RI Miranda, Paulo/C-5933-2012 OI Miranda, Paulo/0000-0002-2890-0268 NR 22 TC 212 Z9 215 U1 9 U2 74 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD DEC 28 PY 1998 VL 81 IS 26 BP 5876 EP 5879 DI 10.1103/PhysRevLett.81.5876 PG 4 WC Physics, Multidisciplinary SC Physics GA 152DG UT WOS:000077760200042 ER PT J AU Nagesha, K Sanche, L AF Nagesha, K Sanche, L TI Effects of band structure on electron attachment to adsorbed molecules: Cross section enhancements via coupling to image states SO PHYSICAL REVIEW LETTERS LA English DT Article ID SURFACE-STATES; THIN-FILMS; SCATTERING; TRANSMISSION; FEMTOSECOND; ALKANES; CH3CL; KR AB Near-zero-energy electrons at the surface of glassy n-hexane (nHg) are strongly trapped by adsorbed molecules, with a cross section 10(2)-10(4) larger than those on the solid Kr surface. This enhancement is attributed to the difference in the band structures of solid nHg and Kr near the vacuum level. C1 Univ Sherbrooke, Fac Med, Grp Conseil Rech Med Sci Radiat, Sherbrooke, PQ J1H 5N4, Canada. RP Nagesha, K (reprint author), Oak Ridge Natl Lab, Div Life Sci, Oak Ridge, TN 37831 USA. NR 26 TC 41 Z9 41 U1 0 U2 3 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD DEC 28 PY 1998 VL 81 IS 26 BP 5892 EP 5895 DI 10.1103/PhysRevLett.81.5892 PG 4 WC Physics, Multidisciplinary SC Physics GA 152DG UT WOS:000077760200046 ER PT J AU Mineev-Weinstein, M AF Mineev-Weinstein, M TI Comment on "Selection of the Saffman-Taylor finger width in the absence of surface tension: An exact result" - Reply SO PHYSICAL REVIEW LETTERS LA English DT Article C1 Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Mineev-Weinstein, M (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, MS-B213, Los Alamos, NM 87545 USA. NR 4 TC 5 Z9 5 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD DEC 28 PY 1998 VL 81 IS 26 BP 5952 EP 5952 DI 10.1103/PhysRevLett.81.5952 PG 1 WC Physics, Multidisciplinary SC Physics GA 152DG UT WOS:000077760200064 ER PT J AU Turteltaub, KW Dingley, KH AF Turteltaub, KW Dingley, KH TI Application of accelerated mass spectrometry (AMS) in DNA adduct quantification and identification SO TOXICOLOGY LETTERS LA English DT Article; Proceedings Paper CT 8th International Congress of Toxicology CY JUL 05-09, 1998 CL PARIS, FRANCE SP Soc Francaise Toxicol DE accelerator mass spectrometry; DNA adduct; low level dosimetry; 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline ID LOW-DOSE EXTRAPOLATION; RISK ASSESSMENT; HUMAN TISSUES; CANCER; CARCINOGENS; DOSIMETRY; ISOTOPE; MEIQX AB DNA adducts are nucleotide bases that have been covalently modified by reactive electrophilic chemical intermediates, and have been extensively researched for their role in mutagenesis and carcinogenesis. However, many DNA adduct measurement techniques have difficulty in the quantification of adducts at realistic human exposure levels. We are using the extremely sensitive analytical technique of accelerator mass spectrometry (AMS) to study adducts either at low dose or directly in humans. AMS is a technique for measuring isotope ratios with high selectivity, attomole sensitivity (10(-18) mol) and precision of 0.5-10%, depending on isotope level and preparation method. This sensitivity and precision is being used to study the dose-response, toxicokinetics, and toxicodynamics of DNA adduct formation and removal following administration of very low doses of chemicals. (C) 1998 Elsevier Science Ireland Ltd. All rights reserved. C1 Univ Calif Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, Livermore, CA 94550 USA. Univ Calif Lawrence Livermore Natl Lab, Ctr Accelerator Mass Spectrometry, Livermore, CA 94550 USA. RP Turteltaub, KW (reprint author), Univ Calif Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, Livermore, CA 94550 USA. NR 23 TC 16 Z9 16 U1 0 U2 0 PU ELSEVIER SCI IRELAND LTD PI CLARE PA CUSTOMER RELATIONS MANAGER, BAY 15, SHANNON INDUSTRIAL ESTATE CO, CLARE, IRELAND SN 0378-4274 J9 TOXICOL LETT JI Toxicol. Lett. PD DEC 28 PY 1998 VL 103 BP 435 EP 439 PG 5 WC Toxicology SC Toxicology GA 164KE UT WOS:000078462400069 ER PT J AU Jensen, EJ Ackerman, AS Stevens, DE Toon, OB Minnis, P AF Jensen, EJ Ackerman, AS Stevens, DE Toon, OB Minnis, P TI Spreading and growth of contrails in a sheared environment SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article AB A case study of persistent contrail evolution in a sheared environment is simulated over time-scales of 15-180 min using a large-eddy simulation model with detailed microphysics. Model results are compared to satellite and in situ measurements of persistent contrails from the Subsonic Aircraft: Contrail and Cloud Effects Special Study (SUCCESS) experiment. In simulations with large ambient supersaturations and moderate wind shear, crystals with lengths >200 mu m are generated within 45 min by depositional growth. These crystals fall rapidly, and the contrail horizontal extent increases due to the wind shear. Strong radiative heating (with rates up to 10 K d(-1)) drives a local updraft and lofts the contrail core several hundred meters. The observed rate of contrail spreading and maintenance of optical depths larger than 0.05 can be approximately explained simply by growth and precipitation of ice crystals nucleated during the initial contrail formation if the environmental humidity is very high (relative humidity with respect to ice >125%). This result is consistent with observed high humidities in regions where persistent contrails formed during SUCCESS. C1 NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. Lawrence Livermore Natl Lab, Div Atmospher Sci, Livermore, CA 94550 USA. Univ Colorado, LASP, Boulder, CO 80309 USA. NASA, Langley Res Ctr, Hampton, VA 23681 USA. RP NASA, Ames Res Ctr, MS 245-4, Moffett Field, CA 94035 USA. EM ejensen@sky.arc.nasa.gov; stevens@mothra.lbl.gov; toon@lasp.colorado.edu; p.minnis@larc.nasa.gov RI Ackerman, Andrew/D-4433-2012; Minnis, Patrick/G-1902-2010 OI Ackerman, Andrew/0000-0003-0254-6253; Minnis, Patrick/0000-0002-4733-6148 NR 24 TC 49 Z9 49 U1 0 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X EI 2169-8996 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD DEC 27 PY 1998 VL 103 IS D24 BP 31557 EP 31567 DI 10.1029/98JD02594 PG 11 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 155VL UT WOS:000077967000004 ER PT J AU Chen, WYC Louck, JD AF Chen, WYC Louck, JD TI The combinatorics of a class of representation functions SO ADVANCES IN MATHEMATICS LA English DT Article ID MACMAHONS MASTER THEOREM; TENSOR OPERATORS; LINEARIZATION COEFFICIENTS; ORTHOGONAL POLYNOMIALS; LAGRANGE INVERSION; UNITARY GROUPS; IDENTITIES; PFAFFIANS; MATRICES; FORMULA AB In the study of the irreducible representations of the unitary group U(n), one encounters a class of polynomials defined on n(2) indeterminates z(ij), 1 less than or equal to i, j less than or equal to n, which may be arranged into an n x n matrix array Z = (z(ij)). These polynomials are indexed by double Gelfand patterns, or equivalently, by pairs of column strict Young tableaux of the same shape. Using the double labeling property, one may define a square matrix D(Z), whose elements are the double-indexed polynomials. These matrices possess the remarkable "group multiplication property" D(XY) = D(X) D(Y) for arbitrary matrices X and Y,even though these matrices may be singular. For Z = U is an element of U(il), these matrices give irreducible unitary representations of Li(n). These results are known, but not always fully proved from the extensive physics literature on representation of the unitary groups, where they are often formulated in terms of the boson calculus, and the multiplication property is unrecognized. The generality of the multiplication property is the key to understanding group representation theory from the purview of combinatories. The combinatorial structure of the general polynomials is expected to be intricate, and in this paper, we take the first step to explore the combinatorial aspects of a special class which can be defined in terms of the set of integral matrices with given row and column sums. These special polynomials are denoted by L-alpha,L-beta(Z), where alpha and beta are integral vectors representing the row sums and column sums of a class of integral matrices. We present a combinatorial interpretation of the multiplicative properties of these polynomials. We also point out the connections with MacMahon's Master Theorem and Schwinger's inner product formula, which is essentially equivalent to MacMahon's Master Theorem. Finally, we give a formula For the double Pfaffian, which is crucial in the studies of the generating function of the 3n - j coefficients in angular momentum theory. We also review the background of the general polynomials and give some of their properties. (C) 1998 Academic Press. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Nankai Univ, Res Ctr Combinator, Tianjin 300071, Peoples R China. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Chen, WYC (reprint author), Univ Calif Los Alamos Natl Lab, T-7,Mail Stop B284, Los Alamos, NM 87545 USA. NR 60 TC 14 Z9 16 U1 1 U2 1 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0001-8708 J9 ADV MATH JI Adv. Math. PD DEC 25 PY 1998 VL 140 IS 2 BP 207 EP 236 DI 10.1006/aima.1998.1769 PG 30 WC Mathematics SC Mathematics GA 151PM UT WOS:000077729600004 ER PT J AU Mourant, JR Hielscher, AH Eick, AA Johnson, TM Freyer, JP AF Mourant, JR Hielscher, AH Eick, AA Johnson, TM Freyer, JP TI Evidence of intrinsic differences in the light scattering properties of tumorigenic and nontumorigenic cells SO CANCER CYTOPATHOLOGY LA English DT Article; Proceedings Paper CT Gordon Research Conference on Lasers in Medicine and Biology CY JUN 14-19, 1998 CL NEW HAMPSHIRE DE cancer diagnosis; light scattering; turbid media; tumorigenesis models ID TISSUE OPTICAL-PROPERTIES; IN-VIVO; NONINVASIVE DETERMINATION; DIFFUSE-REFLECTANCE; BIOLOGICAL TISSUE; REFRACTIVE-INDEX; FLUORESCENCE; DIAGNOSIS; SPECTROSCOPY; FIBROBLASTS AB BACKGROUND. The objective of this study was to determine whether there are intrinsic differences in the light scattering properties of tumorigenic and nontumorigenic cells from a multistep carcinogenesis model. METHODS. Wavelength-dependent and polarization-dependent light scattering properties of cell suspensions were measured. RESULTS, Statistically significant differences were found between the tumorigenic and nontumorigenic cells. CONCLUSIONS. Differences in the light scattering properties of tumorigenic and nontumorigenic cells are attributed to a change in the average size of the scattering centers on the order of a few ten of nanometers. This work is relevant to the development of noninvasive optical methods for cancer diagnosis. Cancer(Cancer Cytopathol) 1998;84:366-74. (C) 1998 American Cancer. Society. C1 Univ Calif Los Alamos Natl Lab, Chem Sci & Technol Div, Biosci & Biotechnol Grp, Los Alamos, NM 87545 USA. Univ Calif Los Alamos Natl Lab, Div Life Sci, Mol & Cellular Biol Grp, Los Alamos, NM 87545 USA. RP Mourant, JR (reprint author), Univ Calif Los Alamos Natl Lab, Chem Sci & Technol Div, Biosci & Biotechnol Grp, MS E535, Los Alamos, NM 87545 USA. FU NCI NIH HHS [1R01CA71898, R01 CA071898]; NIEHS NIH HHS [1R01ES07845] NR 29 TC 90 Z9 91 U1 1 U2 5 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0008-543X J9 CANCER CYTOPATHOL JI Cancer Cytopathol. PD DEC 25 PY 1998 VL 84 IS 6 BP 366 EP 374 DI 10.1002/(SICI)1097-0142(19981225)84:6<366::AID-CNCR9>3.0.CO;2-7 PG 9 WC Oncology; Pathology SC Oncology; Pathology GA 155LP UT WOS:000077948700009 PM 9915139 ER PT J AU Reddy, KB Gascard, P Price, MG Negrescu, EV Fox, JEB AF Reddy, KB Gascard, P Price, MG Negrescu, EV Fox, JEB TI Identification of an interaction between the M-band protein skelemin and beta-integrin subunits - Colocalization of a skelemin-like protein with beta(1)- and beta(3)-integrins in non-muscle cells SO JOURNAL OF BIOLOGICAL CHEMISTRY LA English DT Article ID GLYCOPROTEIN-IIB-IIIA; CYTOPLASMIC DOMAIN MUTANTS; ACTIN STRESS FIBERS; SARCOMERIC M-BAND; FOCAL ADHESIONS; SIGNAL-TRANSDUCTION; TYROSINE PHOSPHORYLATION; EXTRACELLULAR-MATRIX; FIBRONECTIN RECEPTOR; ALPHA-ACTININ AB Signaling across integrins is regulated by interaction of these receptors with cytoskeletal proteins and signaling molecules. To identify molecules interacting with the cytoplasmic domain of the beta(3)-integrin subunit (glycoprotein ma), a placental cDNA library was screened in the yeast two-hybrid system. Two identical clones coding for a 96-amino acid sequence were identified. This sequence was 100% identical to a sequence in skelemin, a protein identified previously in skeletal muscle. Skelemin is a member of a superfamily of cytoskeletal proteins that contain fibronectin-type ill-like motifs and immunoglobulin CB-like motifs and that regulate the organization of myosin filaments in muscle. The amino acid residues in the isolated clones encompassed C2 motifs 4 and 5 of skelemin. A recombinant skelemin protein consisting of C2 motifs 3-7 interacted with beta(1)- and beta(3)-integrin cytoplasmic domains expressed as glutathione S-transferase (GST) fusion proteins, but not with GST-beta(2)-integrin cytoplasmic tail or GST alone. The skelemin-binding region was in the membrane proximal cytoplasmic domains of the integrins, Full-length skelemin interacted with integrin in intact cells as demonstrated by the colocalization of hemagglutinin-tagged skelemin in Chinese hamster ovary (CHO) cells containing alpha(IIb)beta(3)-integrin and by the finding that microinjection of C2 motif 4 of skelemin into C2C12 mouse myoblast cells caused spread cells to round up. A skelemin-like protein was detected in CHO cells, endothelial cells, and platelets, and this protein colocalized with beta(1)- and beta(3)-integrins in CHO cells. This study suggests the presence of a skelemin-like protein in non-muscle cells and provides evidence that it may be involved in linking integrins to the cytoskeleton. C1 Cleveland Clin Fdn, JJ Jacobs Ctr Thrombosis & Vasc Biol, Lerner Res Inst, Dept Mol Cardiol, Cleveland, OH 44195 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Baylor Coll Med, Dept Cell Biol, Houston, TX 77030 USA. RP Fox, JEB (reprint author), Cleveland Clin Fdn, JJ Jacobs Ctr Thrombosis & Vasc Biol, Lerner Res Inst, Dept Mol Cardiol, FF2-04, Cleveland, OH 44195 USA. FU NHLBI NIH HHS [HL30657, HL56264] NR 78 TC 40 Z9 41 U1 0 U2 2 PU AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 USA SN 0021-9258 J9 J BIOL CHEM JI J. Biol. Chem. PD DEC 25 PY 1998 VL 273 IS 52 BP 35039 EP 35047 DI 10.1074/jbc.273.52.35039 PG 9 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 151KR UT WOS:000077719700055 PM 9857037 ER PT J AU Vaniman, D Bish, D Blake, D Elliott, ST Sarrazin, P Collins, SA Chipera, S AF Vaniman, D Bish, D Blake, D Elliott, ST Sarrazin, P Collins, SA Chipera, S TI Landed XRD/XRF analysis of prime targets in the search for past or present Martian life SO JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS LA English DT Article ID MARS; PRESERVATION; FOSSILS; DEVICES AB Mars landers seeking evidence for past or present life will be guided by information from orbital mapping and from previous surface exploration. Several target options have been proposed, including sites that may harbor extant life and sites most likely to preserve evidence of past life. These sites have specific mineralogic characteristics. Extant life might be gathered around the sinters and associated mineral deposits of rare active fumaroles, or held within brine pockets and inclusions in a few evaporite-mineral deposits. Possibilities for fossilization include deltaic and lake-bottom sediments of once-flooded craters, sinters formed by ancient hot-spring deposits, and the carbonate deposits associated with some evaporite systems. However, the highly varied mineralogy of fossil occurrences on Earth leads to the inference that Mars, an equally complex planet, could host a broad variety of potential fossilizing deposits. The abundance of volcanic systems on Mars and evidence for close associations between volcanism and water release suggest possibilities of organism entrapment and mineralization in volcaniclastic deposits, as found in some instances on Earth. Thus the targets being considered for exploration include a wide variety of unique deposits that would be characterized by silica or various nonsilicate minerals. Beyond these "special" deposits and in the most general case, an ability to distinguish mineralized from uncemented volcanic detritus may be the key to success in finding possible fossil-bearing authigenic mineralogies. A prototype miniaturized X ray diffraction/X ray fluorescence (XRD/XRF) instrument has been evaluated with silica, carbonate, and sulfate minerals and with a basalt, to examine the capabilities of this tool in mineralogic and petrologic exploration for exo-biological goals. This instrument, CHEMIN (chemical and mineralogical analyzer), is based on an innovative low-power X ray tube, transmission geometry, and CCD collection and discrimination of diffracted and fluoresced X rays. The ability to accumulate and integrate the entire circumference of each complete Debye diffraction ring compensates for poor powder preparations, as might be produced by robotic sampling systems. With CHEMIN, a wide range of minerals can be uniquely identified. Using Rietveld analysis of the XRD results, mineral quantification is also possible. Expanded capabilities in phase analysis and constrained data solutions using quantitative XRD and XRF are within reach. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Etablissement Natl Enseignement Super Agron Dijon, Lab Genie Agroequipements Procedes, F-21800 Quetigny, France. RP Vaniman, D (reprint author), Univ Calif Los Alamos Natl Lab, MS D462, Los Alamos, NM 87545 USA. NR 41 TC 15 Z9 15 U1 3 U2 14 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-PLANET JI J. Geophys. Res.-Planets PD DEC 25 PY 1998 VL 103 IS E13 BP 31477 EP 31489 DI 10.1029/98JE01428 PG 13 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 154QU UT WOS:000077900600012 PM 11542260 ER PT J AU Buchanan, AC Britt, PF Skeen, JT Struss, JA Elam, CL AF Buchanan, AC Britt, PF Skeen, JT Struss, JA Elam, CL TI Pyrolysis of silica-immobilized benzyl phenyl ether: Competing radical rearrangement pathways under restricted diffusion SO JOURNAL OF ORGANIC CHEMISTRY LA English DT Article ID SOLVENT COAL DISSOLUTION; LOW-RANK COAL; MODEL COMPOUNDS; THERMAL-DECOMPOSITION; HYDROGEN-TRANSFER; ORGANIC-CHEMISTRY; CROSS-LINKING; SOLID-STATE; THERMOLYSIS; SURFACE AB Pyrolysis studies of silica-immobilized benzyl phenyl ether (approximate to PhOCH2Ph or approximate to BPE), a model for related ether structures in fuel resources, have been conducted at 275-325 degrees C to examine the impact of restricted mass transport on the pyrolysis mechanism compared with previous studies in fluid phases. Significant rearrangement chemistry is observed for approximate to BPE occurring through two competitive free-radical pathways that are both promoted by the diffusional constraints. One path involves recombination of incipient benzyl and surface-bound phenoxy radicals to form benzylphenol isomers, 10. The second, previously unreported rearrangement path for approximate to BPE involves a 1,2-phenyl shift in an intermediate radical, approximate to PhOCH . Ph, leading to formation of benzhydrol (8) and benzophenone (9) as principal products. The rearrangement products 8-10 typically account for ca. 50% of the pyrolysis products. However, the path selectivity is a sensitive function of approximate to BPE surface coverage and the presence of spacer molecules that either facilitate or hinder hydrogen atom transfer steps on the surface. C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Buchanan, AC (reprint author), Oak Ridge Natl Lab, Div Chem & Analyt Sci, POB 2008,MS-6197, Oak Ridge, TN 37831 USA. NR 62 TC 30 Z9 30 U1 1 U2 18 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0022-3263 J9 J ORG CHEM JI J. Org. Chem. PD DEC 25 PY 1998 VL 63 IS 26 BP 9895 EP 9903 DI 10.1021/jo9816717 PG 9 WC Chemistry, Organic SC Chemistry GA 153LP UT WOS:000077834800050 ER PT J AU Gibson, JK Haire, RG AF Gibson, JK Haire, RG TI Gas-phase chemistry of curium: Reactions of Cm+ and CmO+ with alkenes, acetonitrile, and hexafluoropropene SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID ORGANOMETALLIC CHEMISTRY; CYCLIC HYDROCARBONS; LANTHANIDE CATIONS; BOND ACTIVATION; OXO-LIGAND; METAL-IONS; C-H; REACTIVITY; BARE; FLUOROCARBONS AB The metal ions, Cm+, U+, and Tb+, and their oxides, MO+, were reacted in the gas phase with alkenes, acetonitrile, and hexafluoropropene. Product compositions and abundances provide a survey of essential aspects of the gas-phase chemistry of the curium cation, now the heaviest element for which such systematic studies have been carried out (U and Tb were included to provide comparisons). Of particular interest is the difference in behavior between the 4f lanthanide and 5f actinide series and variations in chemistry across the actinide series. The primary emphasis was on reactions with alkenes, particularly dehydrogenation, as indicative of the ability of a M+ to activate C-H bonds.(the extent of C-C activation was generally in parallel with that of C-H activation). With acetonitrile and all of the alkenes (except ethene), the three M+ ions induced dehydrogenation. Variations were evident for the different reactant substrates, but the overall qualitative ordering of dehydrogenation efficiency was U+ > Tb+ > Cm+. This order is consistent with the variation in electronic promotion energies (PE) required to provide two spin-unpaired, non-f valence electrons at the M+, i.e., a [Rg]f(n-2)d(1)s(1) configuration ("Rg" = Xe for the lanthanides and Rn for the actinides), Co enable its insertion into a C-H bond. The reduced reactivity of Cm+ relative to U+ and Tb+ suggests that the closed-shell 7s(2) electrons of ground Cm+ (S-8 [Rn]5f(7)s(2)) are ineffective in enabling C-H activation and that promotion to the D-10 [Rn]5f(7)6d(1)7s(1) configuration is prerequisite. The PE[Cm+] (48 kJ mol(-1)) is only slightly greater than PE[Tb+] (39 kJ mol(-1)) and the significantly greater reactivity of Tb+ vs Cm+ may reflect that the transition to the prepared "divalent" state (d(1)s(1)) is parity forbidden for Cm+. The three MO+ were substantially less reactive than the naked M+ but were comparably reactive to one another, consistent with a multicentered activation process, which is less efficient than direct cleavage of a C-H bond by M+ insertion. With hexafluoropropene, the primary reaction channel was F abstraction and the discrepant reactivities reflected the propensity for U to oxidize to higher valence states compared to Cm or Tb. The terminal MFn+ were. (CmF2+)-F-III, (TbF2+)-F-III, and (UF4+)-F-IV, and among the MO+, only UO+ induced F abstraction, producing UOFn+ with n = 1-3. C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Gibson, JK (reprint author), Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. EM gibsonjk@ornl.gov NR 39 TC 19 Z9 19 U1 1 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5639 J9 J PHYS CHEM A JI J. Phys. Chem. A PD DEC 24 PY 1998 VL 102 IS 52 BP 10746 EP 10753 DI 10.1021/jp9836067 PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 153MT UT WOS:000077837400022 ER PT J AU Ruscic, B Michael, JV Redfern, PC Curtiss, LA Raghavachari, K AF Ruscic, B Michael, JV Redfern, PC Curtiss, LA Raghavachari, K TI Simultaneous adjustment of experimentally based enthalpies of formation of CF3X, X = nil, H, Cl, Br, I, CF3, CN, and a probe of G3 theory SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID EQUILIBRIUM-CONSTANTS; GAUSSIAN-2 THEORY; LARGER MOLECULES; 300-700 K; PHOTOIONIZATION; THERMOCHEMISTRY; STATE; ENERGIES; R=CH2CL AB The enthalpies of formation of the title compounds have been determined by simultaneous least-squares solution of a thermochemical network containing 28 experimental measurements extracted from the literature. The new enthalpies differ considerably from the older tabulated values and now show a high degree of internal consistency achieved through excellent agreement with newer experiments, as well as older calorimetric determinations. The fitted values are: Delta H(f298)degrees(CF3)= - 111.3 +/- 0.5 kcal/mol (-110.6 +/- 0.5 kcal/mol at 0 K), Delta H(f298)degrees(CF3H) = -165.6 +/- 0.5 kcal/mol (-163.9 +/- 0.5 kcal/mol at 0 K), Delta H(f298)degrees(CF3Cl) = -169.5 +/- 0.7 kcal/mol (-168.3 +/- 0.7 kcal/mol at 0 K), Delta H(f298)degrees(CF3Br) = -155.3 +/- 0.5 kcal/mol (-152.4 +/- 0.5 kcal/mol at 0 K), bH(f298)degrees(CF3I) = -140.1 +/- 0.5 kcal/mol (-138.7 +/- 0.5 kcal/mol at 0 K), Delta H(f298)degrees(C2F6) = -321.3 +/- 0.8 kcal/mol (-319.3 +/- 0.8 kcal/mol at 0 K), and Delta H(f298)degrees(CF3CN) = 1118.4 +/- 0.4 kcal/mol (-117.5 +/- 0.4 kcal/mol at 0 K). Theoretical calculations at the Gaussian-3 (G3) level of theory have been performed for a subgroup of these molecules, which were problematic at the Gaussian-2 (G2) level of theory. In comparison to G2 theory, the G3 results show a remarkable improvement in accuracy and agree with experiment within <2 kcal/mol. An isodesmic bond-separation scheme brings the calculated values even closer to the experiment. In addition, the G3 value for the ionization energy of CF3, 9.08 eV, was found to be in good agreement with the recent experimental value of 9.05(5) +/- 0.01(1) eV. Further indications that the experimental value for Delta H(f)degrees(C2F4) is probably too high are also presented. C1 Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. AT&T Bell Labs, Lucent Technol, Murray Hill, NJ 07974 USA. RP Ruscic, B (reprint author), Argonne Natl Lab, Div Chem, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Michael, Joe/E-3907-2010; Ruscic, Branko/A-8716-2008 OI Ruscic, Branko/0000-0002-4372-6990 NR 73 TC 66 Z9 67 U1 0 U2 5 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5639 J9 J PHYS CHEM A JI J. Phys. Chem. A PD DEC 24 PY 1998 VL 102 IS 52 BP 10889 EP 10899 DI 10.1021/jp983237e PG 11 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 153MT UT WOS:000077837400040 ER PT J AU Schaaff, TG Knight, G Shafigullin, MN Borkman, RF Whetten, RL AF Schaaff, TG Knight, G Shafigullin, MN Borkman, RF Whetten, RL TI Isolation and selected properties of a 10.4 kDa Gold : Glutathione cluster compound SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Letter ID SELF-ASSEMBLED MONOLAYERS; AU CLUSTERS; MOLECULES; DYNAMICS; COLLOIDS; SPECTRA; SURFACE AB An unprecedented small thioaurite cluster compound (with metallic Au-0 core) has been isolated in high yield by decomposition of polymeric Au(I)SG compounds, where GSH is the ubiquitous tripeptide glutathione, N-gamma-glutamyl-cysteinyl-glycine. The Au:SG clusters appear to share the high stability and robustness of their hydrophobic n-alkyl analogues but are highly water soluble. The most abundant cluster produced by these methods can be easily separated from its homologues by gel electrophoresis. Its total molecular weight is ca. 10.4 kDa, and the mass of its strongly bound inorganic core is 5.6 kDa, suggesting the composition AU(28)(SG)(16) This composition is also consistent with the X-ray diffraction pattern of the crystalline molecular solid. Distinct features in the optical absorption spectroscopy are inherently different from either larger clusters or smaller gold duster compounds. The compound is optically active, as evidenced by circular dichroism in the near-iii, visible, and near-UV regions. The C-13 NMR spectra suggest that the bonding environment of the GS-adsorbate is similar to that of the n-alkyl-adsorbate dusters, and the nonsulfhydryl properties are retained. The cluster is thus envisioned as a large metallic-cluster compound with distinctive optical properties encapsulated by a bioactive peptide monolayer. C1 Georgia Inst Technol, Sch Chem, Atlanta, GA 30332 USA. Georgia Inst Technol, Sch Phys, Atlanta, GA 30332 USA. RP Schaaff, TG (reprint author), Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. NR 20 TC 433 Z9 436 U1 9 U2 72 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5647 J9 J PHYS CHEM B JI J. Phys. Chem. B PD DEC 24 PY 1998 VL 102 IS 52 BP 10643 EP 10646 DI 10.1021/jp9830528 PG 4 WC Chemistry, Physical SC Chemistry GA 153MQ UT WOS:000077837200001 ER PT J AU Ressler, T Wong, J Elmer, JW AF Ressler, T Wong, J Elmer, JW TI Investigation of real-time microstructure evolution in steep thermal gradients using in-situ spatially resolved X-ray diffraction: A case study for Ti fusion welds SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID SYNCHROTRON-RADIATION; TRANSFORMATION AB A recently developed spatially resolved X-ray diffraction (SRXRD) technique utilizing intense synchrotron radiation has been refined to yield phase and microstructural information down to 200 mu m in spatial extent in materials subjected to steep thermal gradients during processing. This SRXRD technique has been applied to map completely the phases and their solid-state transformation in the so-called heat-affected zone (HAZ) in titanium fusion welds in situ during the welding process. Detailed profile analysis of the SRXRD patterns revealed four principal microstructural regions at temperature in the vicinity of the HAZ surrounding the liquid weld pool: (i) a completely transformed beta-Ti zone 2-3 mm adjacent to the liquid weld pool; (ii) a mixed alpha+beta-Ti region surrounding the pure beta-Ti zone, (iii) a back-transformed alpha-Ti zone on the backside of the HAZ where pure beta-Ti once existed at temperature well above the alpha --> beta transformation isotherm, and (iv) a more diffused region outside the HAZ where annealing and recrystallization of the alpha-Ti base metal occur. The high-temperature microstructures so derived corroborate well the expected transformation kinetics in pure titanium, and the observed phase transformation boundaries are in good agreement with those predicted from the transformation isotherms calculated from a simplified heat-flow model. Based on a detailed assessment of the SRXRD setup employed, improved experimentations such as a smaller beam spot emitted from third generation synchrotron sources, better mechanical stability (tighter scattering geometry), and use of an area detector would enable more quantitative structural information for future phase dynamics studies exemplified by this work. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Wong, J (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808, Livermore, CA 94551 USA. NR 19 TC 18 Z9 18 U1 0 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5647 J9 J PHYS CHEM B JI J. Phys. Chem. B PD DEC 24 PY 1998 VL 102 IS 52 BP 10724 EP 10735 DI 10.1021/jp983045j PG 12 WC Chemistry, Physical SC Chemistry GA 153MQ UT WOS:000077837200013 ER PT J AU Chumanov, G Sibbald, MS Cotton, TM AF Chumanov, G Sibbald, MS Cotton, TM TI Low-temperature resonance Raman scattering from iodide adsorbed on nanostructured silver surfaces SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID GOLD ELECTRODES; HALIDE; AG(111); ELECTROCHEMISTRY; SPECTROSCOPY; DEPENDENCE; MICROSCOPY; MATRICES; SPECTRA; ATOMS AB An overtone progression was observed in Raman scattering spectra from iodide-modified, electrochemically roughened silver surfaces at low temperatures. Spectral intensities of the bands were found to vary with the degree of surface roughening, whereas vibrational frequencies remained highly conserved. Both surface-enhanced and resonance scattering phenomena contribute to observed band intensities when excited in the spectral region between 406 and 415 nm. It is suggested that the progression originates from I-2-like species that are formed on small silver clusters at low temperatures under irradiation. This complex can be viewed as a supermolecule in which the electronic resonance is determined by the size of the cluster and I-I stretch represents a normal mode of the molecule. C1 US DOE, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Chem, Ames, IA 50011 USA. RP Chumanov, G (reprint author), US DOE, Ames Lab, Ames, IA 50011 USA. NR 29 TC 5 Z9 5 U1 2 U2 8 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5647 J9 J PHYS CHEM B JI J. Phys. Chem. B PD DEC 24 PY 1998 VL 102 IS 52 BP 10836 EP 10841 DI 10.1021/jp982523n PG 6 WC Chemistry, Physical SC Chemistry GA 153MQ UT WOS:000077837200024 ER PT J AU Ko, CM Wang, XN Zhang, B Zhang, XF AF Ko, CM Wang, XN Zhang, B Zhang, XF TI Charmonium production from hot hadronic matter SO PHYSICS LETTERS B LA English DT Article ID HEAVY-ION COLLISIONS; NUCLEUS-NUCLEUS COLLISIONS; PHI-MESON PRODUCTION; QUARK-GLUON PLASMA; J-PSI-SUPPRESSION; J/PSI AB Charmonium production from D (D) over bar annihilation in the hadron gas formed in ultra-relativistic heavy-ion collisions is studied. With initial conditions taken from the HIJING parton model, we have estimated the number of J/psi produced from an expanding hadron gas, using the J/psi absorption and production cross sections obtained from either an effective Lagrangian or the quark-exchange model. We find that J/psi production is negligible in heavy-ion collisions at the Relativistic Heavy Ion Collider (RHIC) but may be important at the Large Hadron Collider (LHC), where more charm mesons are produced. Similar results are obtained for psi' production from the hadron gas at RHIC and LHC. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Texas A&M Univ, Inst Cyclotron, College Stn, TX 77843 USA. Texas A&M Univ, Dept Phys, College Stn, TX 77843 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. RP Ko, CM (reprint author), Texas A&M Univ, Inst Cyclotron, College Stn, TX 77843 USA. EM ko@comp.tamu.edu; xnwang@nta2.lbl.gov; bzhang@comp.tamu.edu OI Wang, Xin-Nian/0000-0002-9734-9967 NR 33 TC 35 Z9 35 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 J9 PHYS LETT B JI Phys. Lett. B PD DEC 24 PY 1998 VL 444 IS 3-4 BP 237 EP 244 DI 10.1016/S0370-2693(98)01390-2 PG 8 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 158DJ UT WOS:000078100500002 ER PT J AU Lin, ZW Wang, XN AF Lin, ZW Wang, XN TI Enhancement of intermediate mass dileptons from charm decays at SPS energies SO PHYSICS LETTERS B LA English DT Article ID HEAVY-ION COLLISIONS; QUARK-GLUON PLASMA; PHOTON PRODUCTION; DISTRIBUTIONS AB We study the dimuon yield from open charm decays in the intermediate mass region(IMR) in heavy-ion collisions at the CERN-SPS energy. We find that final state rescatterings which broaden the m(T) spectrum of charmed masons can enrich the part of the phase space covered by the NA50 experiment, thus lead to an apparent enhancement of IMR dileptons within the acceptance of the experiment. Such an enhancement increases with the dimuon invariant mass and the single muon energy cut-off. (C) 1998 Published by Elsevier Science B.V. All rights reserved. C1 LBNL, Div Nucl Sci, Berkeley, CA 94720 USA. Univ Washington, Inst Nucl Theory, Seattle, WA 98195 USA. RP Lin, ZW (reprint author), LBNL, Div Nucl Sci, Berkeley, CA 94720 USA. OI Wang, Xin-Nian/0000-0002-9734-9967 NR 31 TC 33 Z9 34 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 J9 PHYS LETT B JI Phys. Lett. B PD DEC 24 PY 1998 VL 444 IS 3-4 BP 245 EP 251 DI 10.1016/S0370-2693(98)01389-6 PG 7 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 158DJ UT WOS:000078100500003 ER PT J AU Howell, CR Chen, Q Carman, TS Hussein, A Gibbs, WR Gibson, BF Mertens, G Moore, CF Morris, C Obst, A Pasyuk, E Roper, CD Salinas, F Slaus, I Sterbenz, S Tornow, W Walter, RL Whiteley, CR Whitton, M AF Howell, CR Chen, Q Carman, TS Hussein, A Gibbs, WR Gibson, BF Mertens, G Moore, CF Morris, C Obst, A Pasyuk, E Roper, CD Salinas, F Slaus, I Sterbenz, S Tornow, W Walter, RL Whiteley, CR Whitton, M TI Toward a resolution of the neutron-neutron scattering-length issue SO PHYSICS LETTERS B LA English DT Article DE E pi(-)d three-nucleon force scattering length ID DEUTERON BREAKUP EXPERIMENTS; EFFECTIVE-RANGE PARAMETERS; PI-D->GAMMA-NN; ANN AB We report a high-precision determination of the S-1(0) neutron-neutron scattering length (a(nn)) using the H-2(pi-,n gamma)n reaction. The value obtained in the present work is - 18.50 +/- 0.05(statistical) +/- 0.44(systematic) +/- 0.30(theoretical) fm, which is consistent with the values from, previous measurements. Combining our result with previous measurements reduces the total uncertainty in the world average of a(nn) to +/-0.4 fm, matching the accuracy to which the charge-symmetric parameter a(pp) is determined. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Duke Univ, Durham, NC 27706 USA. Triangle Univ Nucl Lab, Durham, NC 27706 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA USA. Univ No British Columbia, Prince George, BC V2L 5P2, Canada. New Mexico State Univ, Las Cruces, NM 88003 USA. Univ Tubingen, D-72074 Tubingen, Germany. Univ Texas, Austin, TX 78712 USA. Joint Inst Nucl Res, Dubna, Russia. Rudjer Boskovic Inst, Zagreb, Croatia. RP Howell, CR (reprint author), Duke Univ, Durham, NC 27706 USA. NR 27 TC 65 Z9 66 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 J9 PHYS LETT B JI Phys. Lett. B PD DEC 24 PY 1998 VL 444 IS 3-4 BP 252 EP 259 DI 10.1016/S0370-2693(98)01386-0 PG 8 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 158DJ UT WOS:000078100500004 ER PT J AU Bern, Z Dixon, L Perelstein, M Rozowsky, JS AF Bern, Z Dixon, L Perelstein, M Rozowsky, JS TI One-loop n-point helicity amplitudes in (self-dual) gravity SO PHYSICS LETTERS B LA English DT Article ID YANG-MILLS THEORY; GAUGE-THEORIES; MULTIPLE BREMSSTRAHLUNG; SCATTERING-AMPLITUDES; QCD AMPLITUDES; LIGHT-CONE; STRINGS; COLOR; GLUON; INSTANTONS AB We present an ansatz for all one-loop amplitudes in pure Einstein gravity for which the n external gravitons have the same outgoing helicity. These loop amplitudes, which are rational functions of the momenta, also arise in the quantization of self-dual gravity in four-dimensional Minkowski space. Our ansatz agrees with explicit computations via D-dimensional unitarity cuts for n less than or equal to 6. It also has the expected analytic behavior, for all n, as a graviton becomes soft, and as two momenta become collinear. The gravity results are closely related to analogous amplitudes in (self-dual) Yang-Mills theory. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Univ Calif Los Angeles, Dept Phys, Los Angeles, CA 90095 USA. Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. Univ Florida, Dept Phys, Inst Fundamental Theory, Gainesville, FL 32611 USA. RP Bern, Z (reprint author), Univ Calif Los Angeles, Dept Phys, Los Angeles, CA 90095 USA. NR 65 TC 26 Z9 26 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 J9 PHYS LETT B JI Phys. Lett. B PD DEC 24 PY 1998 VL 444 IS 3-4 BP 273 EP 283 DI 10.1016/S0370-2693(98)01397-5 PG 11 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 158DJ UT WOS:000078100500007 ER PT J AU Antoniadis, I Mazur, PO Mottola, E AF Antoniadis, I Mazur, PO Mottola, E TI Fractal geometry of quantum spacetime at large scales SO PHYSICS LETTERS B LA English DT Article ID CONFORMAL SYMMETRY; RANDOM SURFACES; GRAVITY; TRIANGULATION; DIMENSIONS; MATTER; SECTOR; MODELS; 2D AB We compute the intrinsic Hausdorff dimension of spacetime at the infrared fixed point of the quantum conformal factor in 4D gravity. The fractal dimension is defined by the appropriate covariant diffusion equation in four dimensions and is determined by the coefficient of the Gauss-Bonnet term in the trace anomaly to be generally greater than 4. In addition to being testable in simplicial simulations, this scaling behavior suggests a physical mechanism for the screening of the effective cosmological 'constant' and inverse Newtonian coupling at very large distance scales, which has implications for the dark matter content and large scale structure of the universe. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Ecole Polytech, Ctr Phys Theor, F-91128 Palaiseau, France. Univ S Carolina, Dept Phys & Astron, Columbia, SC 29208 USA. Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Antoniadis, I (reprint author), Ecole Polytech, Ctr Phys Theor, F-91128 Palaiseau, France. EM antoniad@cpht.polytechnique.fr; mazur@psc.psc.sc.edu; emil@pion.lanl.gov OI Mazur, Pawel/0000-0002-1679-3637 NR 41 TC 29 Z9 30 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 J9 PHYS LETT B JI Phys. Lett. B PD DEC 24 PY 1998 VL 444 IS 3-4 BP 284 EP 292 DI 10.1016/S0370-2693(98)01375-6 PG 9 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 158DJ UT WOS:000078100500008 ER PT J AU Acciarri, M Adriani, O Aguilar-Benitez, M Ahlen, S Alcaraz, J Alemanni, G Allaby, J Aloisio, A Alviggi, MG Ambrosi, G Anderhub, H Andreev, VP Angelescu, T Anselmo, F Arefiev, A Azemoon, T Aziz, T Bagnaia, P Baksay, L Banerjee, S Banerjee, S Banicz, K Barczyk, A Barillere, R Barone, L Bartalini, P Baschirotto, A Basile, M Battiston, R Bay, A Becattini, F Becker, U Behner, F Berdugo, J Berges, P Bertucci, B Betev, BL Bhattacharya, S Biasini, M Biland, A Bilei, GM Blaising, JJ Blyth, SC Bobbink, GJ Bock, R Bohm, A Boldizsar, L Borgia, B Bourilkov, D Bourquin, M Braccini, S Branson, JG Brigljevic, V Brock, IC Buffini, A Buijs, A Burger, JD Burger, WJ Busenitz, J Button, A Cai, XD Campanelli, M Capell, M Romeo, GC Carlino, G Cartacci, AM Casaus, J Castellini, G Cavallari, F Cavallo, N Cecchi, C Cerrada, M Cesaroni, F Chamizo, M Chang, YH Chaturvedi, UK Chemarin, M Chen, A Chen, G Chen, GM Chen, HF Chen, HS Chereau, X Chiefari, G Chien, CY Cifarelli, L Cindolo, F Civinini, C Clare, I Clare, R Coignet, G Colijn, AP Colino, N Costantini, S Cotorobai, F de la Cruz, B Csilling, A Dai, TS D'Alessandro, R de Asmundis, R Degre, A Deiters, K della Volpe, D Denes, P DeNotaristefani, F Diemoz, M van Dierendonck, D Di Lodovico, F Dionisi, C Dittmar, M Dominguez, A Doria, A Dova, MT Duchesneau, D Duinker, P Duran, I Easo, S El Mamouni, H Engler, A Eppling, FJ Erne, FC Extermann, P Fabre, M Faccini, R Falagan, MA Falciano, S Favara, A Fay, J Fedin, O Felcini, M Ferguson, T Ferroni, F Fesefeldt, H Fiandrini, E Field, JH Filthaut, F Fisher, PH Fisk, I Forconi, G Fredj, L Freudenreich, K Furetta, C Galaktionov, Y Ganguli, SN Garcia-Abia, P Gataullin, M Gau, SS Gentile, S Gheordanescu, N Giagu, S Goldfarb, S Goldstein, J Gong, ZF Gougas, A Gratta, G Gruenewald, MW van Gulik, R Gupta, VK Gurtu, A Gutay, LJ Haas, D Hartmann, B Hasan, A Hatzifotiadou, D Hebbeker, T Herve, A Hidas, P Hirschfelder, J van Hoek, WC Hofer, H Hoorani, H Hou, SR Hu, G Iashvili, I Jin, BN Jones, LW de Jong, P Josa-Mutuberria, I Khan, RA Kamrad, D Kapustinsky, JS Kaur, M Kienzle-Focacci, MN Kim, D Kim, DH Kim, JK Kirn, SC Kinnison, WW Kirkby, A Kirkby, D Kirkby, J Kiss, D Kittel, W Klimentov, A Konig, AC Kopp, A Korolko, I Koutsenko, V Kraemer, RW Krenz, W Kunin, A Lacentre, P de Guevara, PL Laktineh, I Landi, G Lapoint, C Lassila-Perini, K Laurikainen, P Lavorato, A Lebeau, M Lebedev, A Lebrun, P Lecomte, P Lecoq, P Le Coultre, P Lee, HJ Le Goff, JM Leiste, R Leonardi, E Levtchenko, P Li, C Lin, CH Lin, WT Linde, FL Lista, L Liu, ZA Lohmann, W Longo, E Lu, W Lu, YS Lubelsmeyer, K Luci, C Luckey, D Luminari, L Lustermann, W Ma, WG Maity, M Majumder, G Malgeri, L Malinin, A Mana, C Mangeol, D Marchesini, P Marian, G Marin, A Martin, JP Marzano, F Massaro, GGG Mazumdar, K McNeil, RR Mele, S Merola, L Meschini, M Metzger, WJ von der Mey, M Migani, D Mihul, A van Mil, AJW Milcent, H Mirabelli, G Mnich, J Molnar, P Monteleoni, B Moore, R Moulik, T Mount, R Muanza, GS Muheim, F Muijs, AJM Nahn, S Napolitano, M Nessi-Tedaldi, F Newman, H Niessen, G Nippe, A Nisati, A Nowak, H Oh, YD Organtini, G Ostonen, R Palomares, C Pandoulas, D Paoletti, S Paolucci, P Park, HK Park, IH Pascale, G Passaleva, G Patricelli, S Paul, T Pauluzzi, M Paus, C Pauss, F Peach, D Pedace, M Pei, YJ Pensotti, S Perret-Gallix, D Petersen, B Petrak, S Pevsner, A Piccolo, D Pieri, M Piroue, PA Pistolesi, E Plyaskin, V Pohl, M Pojidaev, V Postema, H Pothier, J Produit, N Prokofiev, D Quartieri, J Rahal-Callot, G Raja, N Rancoita, PG Rattaggi, M Raven, G Razis, P Ren, D Rescigno, M Reucroft, S van Rhee, T Riemann, S Riles, K Robohm, A Rodin, J Roe, BP Romero, L Rosier-Lees, S Roth, S Rubio, JA Ruschmeier, D Rykaczewski, H Sakar, S Salicio, J Sanchez, E Sanders, MP Sarakinos, ME Schafer, C Schegelsky, V Schmidt-Kaerst, S Schmitz, D Scholz, N Schopper, H Schotanus, DJ Schwenke, J Schwering, G Sciacca, C Sciarrino, D Servoli, L Shevchenko, S Shivarov, N Shoutko, V Shukla, J Shumilov, E Shvorob, A Siedenburg, T Son, D Smith, B Spillantini, P Steuer, M Stickland, DP Stone, A Stone, H Stoyanov, B Straessner, A Sudhakar, K Sultanov, G Sun, LZ Susinno, GF Suter, H Swain, JD Szillasi, Z Tang, XW Tauscher, L Taylor, L Timmermans, C Ting, SCC Ting, SM Tonwar, SC Toth, J Tully, C Tung, KL Uchida, Y Ulbricht, J Valente, E Vesztergombi, G Vetlitsky, I Viertel, G Villa, S Vivargent, M Vlachos, S Vogel, H Vogt, H Vorobiev, I Vorobyov, AA Vorvolakos, A Wadhwa, M Wallraff, W Wang, JC Wang, XL Wang, ZM Weber, A Wu, SX Wynhoff, S Xu, J Xu, ZZ Yang, BZ Yang, CG Yang, HJ Yang, M Ye, JB Yeh, SC You, JM Zalite, A Zalite, Y Zemp, P Zeng, Y Zhang, ZP Zhou, B Zhu, GY Zhu, RY Zichichi, A Ziegler, F Zilizi, G AF Acciarri, M Adriani, O Aguilar-Benitez, M Ahlen, S Alcaraz, J Alemanni, G Allaby, J Aloisio, A Alviggi, MG Ambrosi, G Anderhub, H Andreev, VP Angelescu, T Anselmo, F Arefiev, A Azemoon, T Aziz, T Bagnaia, P Baksay, L Banerjee, S Banerjee, S Banicz, K Barczyk, A Barillere, R Barone, L Bartalini, P Baschirotto, A Basile, M Battiston, R Bay, A Becattini, F Becker, U Behner, F Berdugo, J Berges, P Bertucci, B Betev, BL Bhattacharya, S Biasini, M Biland, A Bilei, GM Blaising, JJ Blyth, SC Bobbink, GJ Bock, R Bohm, A Boldizsar, L Borgia, B Bourilkov, D Bourquin, M Braccini, S Branson, JG Brigljevic, V Brock, IC Buffini, A Buijs, A Burger, JD Burger, WJ Busenitz, J Button, A Cai, XD Campanelli, M Capell, M Romeo, GC Carlino, G Cartacci, AM Casaus, J Castellini, G Cavallari, F Cavallo, N Cecchi, C Cerrada, M Cesaroni, F Chamizo, M Chang, YH Chaturvedi, UK Chemarin, M Chen, A Chen, G Chen, GM Chen, HF Chen, HS Chereau, X Chiefari, G Chien, CY Cifarelli, L Cindolo, F Civinini, C Clare, I Clare, R Coignet, G Colijn, AP Colino, N Costantini, S Cotorobai, F de la Cruz, B Csilling, A Dai, TS D'Alessandro, R de Asmundis, R Degre, A Deiters, K della Volpe, D Denes, P DeNotaristefani, F Diemoz, M van Dierendonck, D Di Lodovico, F Dionisi, C Dittmar, M Dominguez, A Doria, A Dova, MT Duchesneau, D Duinker, P Duran, I Easo, S El Mamouni, H Engler, A Eppling, FJ Erne, FC Extermann, P Fabre, M Faccini, R Falagan, MA Falciano, S Favara, A Fay, J Fedin, O Felcini, M Ferguson, T Ferroni, F Fesefeldt, H Fiandrini, E Field, JH Filthaut, F Fisher, PH Fisk, I Forconi, G Fredj, L Freudenreich, K Furetta, C Galaktionov, Y Ganguli, SN Garcia-Abia, P Gataullin, M Gau, SS Gentile, S Gheordanescu, N Giagu, S Goldfarb, S Goldstein, J Gong, ZF Gougas, A Gratta, G Gruenewald, MW van Gulik, R Gupta, VK Gurtu, A Gutay, LJ Haas, D Hartmann, B Hasan, A Hatzifotiadou, D Hebbeker, T Herve, A Hidas, P Hirschfelder, J van Hoek, WC Hofer, H Hoorani, H Hou, SR Hu, G Iashvili, I Jin, BN Jones, LW de Jong, P Josa-Mutuberria, I Khan, RA Kamrad, D Kapustinsky, JS Kaur, M Kienzle-Focacci, MN Kim, D Kim, DH Kim, JK Kirn, SC Kinnison, WW Kirkby, A Kirkby, D Kirkby, J Kiss, D Kittel, W Klimentov, A Konig, AC Kopp, A Korolko, I Koutsenko, V Kraemer, RW Krenz, W Kunin, A Lacentre, P de Guevara, PL Laktineh, I Landi, G Lapoint, C Lassila-Perini, K Laurikainen, P Lavorato, A Lebeau, M Lebedev, A Lebrun, P Lecomte, P Lecoq, P Le Coultre, P Lee, HJ Le Goff, JM Leiste, R Leonardi, E Levtchenko, P Li, C Lin, CH Lin, WT Linde, FL Lista, L Liu, ZA Lohmann, W Longo, E Lu, W Lu, YS Lubelsmeyer, K Luci, C Luckey, D Luminari, L Lustermann, W Ma, WG Maity, M Majumder, G Malgeri, L Malinin, A Mana, C Mangeol, D Marchesini, P Marian, G Marin, A Martin, JP Marzano, F Massaro, GGG Mazumdar, K McNeil, RR Mele, S Merola, L Meschini, M Metzger, WJ von der Mey, M Migani, D Mihul, A van Mil, AJW Milcent, H Mirabelli, G Mnich, J Molnar, P Monteleoni, B Moore, R Moulik, T Mount, R Muanza, GS Muheim, F Muijs, AJM Nahn, S Napolitano, M Nessi-Tedaldi, F Newman, H Niessen, G Nippe, A Nisati, A Nowak, H Oh, YD Organtini, G Ostonen, R Palomares, C Pandoulas, D Paoletti, S Paolucci, P Park, HK Park, IH Pascale, G Passaleva, G Patricelli, S Paul, T Pauluzzi, M Paus, C Pauss, F Peach, D Pedace, M Pei, YJ Pensotti, S Perret-Gallix, D Petersen, B Petrak, S Pevsner, A Piccolo, D Pieri, M Piroue, PA Pistolesi, E Plyaskin, V Pohl, M Pojidaev, V Postema, H Pothier, J Produit, N Prokofiev, D Quartieri, J Rahal-Callot, G Raja, N Rancoita, PG Rattaggi, M Raven, G Razis, P Ren, D Rescigno, M Reucroft, S van Rhee, T Riemann, S Riles, K Robohm, A Rodin, J Roe, BP Romero, L Rosier-Lees, S Roth, S Rubio, JA Ruschmeier, D Rykaczewski, H Sakar, S Salicio, J Sanchez, E Sanders, MP Sarakinos, ME Schafer, C Schegelsky, V Schmidt-Kaerst, S Schmitz, D Scholz, N Schopper, H Schotanus, DJ Schwenke, J Schwering, G Sciacca, C Sciarrino, D Servoli, L Shevchenko, S Shivarov, N Shoutko, V Shukla, J Shumilov, E Shvorob, A Siedenburg, T Son, D Smith, B Spillantini, P Steuer, M Stickland, DP Stone, A Stone, H Stoyanov, B Straessner, A Sudhakar, K Sultanov, G Sun, LZ Susinno, GF Suter, H Swain, JD Szillasi, Z Tang, XW Tauscher, L Taylor, L Timmermans, C Ting, SCC Ting, SM Tonwar, SC Toth, J Tully, C Tung, KL Uchida, Y Ulbricht, J Valente, E Vesztergombi, G Vetlitsky, I Viertel, G Villa, S Vivargent, M Vlachos, S Vogel, H Vogt, H Vorobiev, I Vorobyov, AA Vorvolakos, A Wadhwa, M Wallraff, W Wang, JC Wang, XL Wang, ZM Weber, A Wu, SX Wynhoff, S Xu, J Xu, ZZ Yang, BZ Yang, CG Yang, HJ Yang, M Ye, JB Yeh, SC You, JM Zalite, A Zalite, Y Zemp, P Zeng, Y Zhang, ZP Zhou, B Zhu, GY Zhu, RY Zichichi, A Ziegler, F Zilizi, G TI Single and multi-photon events with missing energy in e(+)e(-) collisions at root s = 183 GeV SO PHYSICS LETTERS B LA English DT Article ID ELECTRON-POSITRON COLLISIONS; LIGHT GRAVITINO; E+E ANNIHILATION; L3 EXPERIMENT; BHABHA SCATTERING; MONTE-CARLO; SUPERSYMMETRY; DETECTOR; LEP; SCALE AB An analysis of single and multi-photon events with missing energy is performed using data collected with the L3 detector at LEP at centre-of-mass energies around 183 GeV, for a total of 55.3 pb(-1) of integrated luminosity. The results obtained are in good agreement with the Standard Model prediction and are used to derive the value for the e(+)e(-) --> v (v) over bar gamma(gamma) cross section as well as upper limits on ness sections of new physics processes. Several interpretations in supersymmetric models providing new limits on the masses of the lightest neutralino and of the gravitino are presented. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Ist Nazl Fis Nucl, Sez Milano, I-20133 Milan, Italy. Rhein Westfal TH Aachen, Inst Phys 1, D-52056 Aachen, Germany. Rhein Westfal TH Aachen, Inst Phys 3, D-52056 Aachen, Germany. NIKHEF H, Natl Inst High Energy Phys, NL-1009 DB Amsterdam, Netherlands. Univ Amsterdam, NL-1009 DB Amsterdam, Netherlands. Univ Michigan, Ann Arbor, MI 48109 USA. CNRS, IN2P3, LAPP, Lab Annecy Le Vieux Phys Particules, F-74941 Annecy Le Vieux, France. Johns Hopkins Univ, Baltimore, MD 21218 USA. Univ Basel, Inst Phys, CH-4056 Basel, Switzerland. Louisiana State Univ, Baton Rouge, LA 70803 USA. Inst High Energy Phys, Beijing 100039, Peoples R China. Humboldt Univ, D-10099 Berlin, Germany. Univ Bologna, I-40126 Bologna, Italy. Ist Nazl Fis Nucl, Sez Bologna, I-40126 Bologna, Italy. Tata Inst Fundamental Res, Bombay 400005, Maharashtra, India. Boston Univ, Boston, MA 02215 USA. Northeastern Univ, Boston, MA 02115 USA. Inst Atom Phys, R-76900 Bucharest, Romania. Univ Bucharest, R-76900 Bucharest, Romania. Hungarian Acad Sci, Cent Res Inst Phys, H-1525 Budapest 114, Hungary. MIT, Cambridge, MA 02139 USA. Ist Nazl Fis Nucl, Sez Firenze, I-50125 Florence, Italy. Univ Florence, I-50125 Florence, Italy. CERN, European Lab Particle Phys, CH-1211 Geneva 23, Switzerland. FBLJA Project, World Lab, CH-1211 Geneva 23, Switzerland. Univ Geneva, CH-1211 Geneva 4, Switzerland. Univ Sci & Technol China, USTC, Hefei 230029, Anhui, Peoples R China. Res Inst High Energy Phys, SEFT, SF-00014 Helsinki, Finland. Univ Lausanne, CH-1015 Lausanne, Switzerland. Ist Nazl Fis Nucl, Sez Lecce, I-73100 Lecce, Italy. Univ Lecce, I-73100 Lecce, Italy. Los Alamos Natl Lab, Los Alamos, NM 87544 USA. Univ Lyon 1, CNRS, IN2P3, Inst Phys Nucl Lyon, F-69622 Villeurbanne, France. CIEMAT, Ctr Invest Energet Medioambientales & Tecnol, E-28040 Madrid, Spain. Ist Nazl Fis Nucl, Sez Napoli, I-80125 Naples, Italy. Univ Naples Federico II, I-80125 Naples, Italy. Univ Cyprus, Dept Nat Sci, Nicosia, Cyprus. Catholic Univ Nijmegen, NL-6525 ED Nijmegen, Netherlands. Natl Inst Nucl Phys & High Energy Phys, NL-6525 ED Nijmegen, Netherlands. CALTECH, Pasadena, CA 91125 USA. Ist Nazl Fis Nucl, Sez Perugia, I-01600 Perugia, Italy. Univ Perugia, I-06100 Perugia, Italy. Carnegie Mellon Univ, Pittsburgh, PA 15213 USA. Princeton Univ, Princeton, NJ 08544 USA. Univ Roma La Sapienza, I-00185 Rome, Italy. Ist Nazl Fis Nucl, Sez Roma, I-00185 Rome, Italy. Inst Phys Nucl, St Petersburg, Russia. Univ Salerno, I-84100 Salerno, Italy. Ist Nazl Fis Nucl, I-84100 Salerno, Italy. Univ Calif San Diego, La Jolla, CA 92093 USA. Univ Santiago Compostela, Dept Fis Particulas Elementales, E-15706 Santiago, Spain. Bulgarian Acad Sci, Cent Lab Mechatron & Instrumentat, BU-1113 Sofia, Bulgaria. Korea Adv Inst Sci & Technol, Ctr High Energy Phys, Taejon 305701, South Korea. Univ Alabama, Tuscaloosa, AL 35486 USA. Univ Utrecht, NL-3584 CB Utrecht, Netherlands. NIKHEF H, NL-3584 CB Utrecht, Netherlands. Purdue Univ, W Lafayette, IN 47907 USA. Paul Scherrer Inst, CH-5232 Villigen, Switzerland. DESY, Inst Hochenergiephys, D-15738 Zeuthen, Germany. Swiss Fed Inst Technol, CH-8093 Zurich, Switzerland. Univ Hamburg, D-22761 Hamburg, Germany. Natl Cent Univ, Chungli 32054, Taiwan. Natl Tsing Hua Univ, Dept Phys, Hsinchu, Taiwan. RP Ist Nazl Fis Nucl, Sez Milano, Via Celoria 16, I-20133 Milan, Italy. RI Berdugo, Javier/A-2858-2015; D'Alessandro, Raffaello/F-5897-2015; Fiandrini, Emanuele/C-4549-2008; Lista, Luca/C-5719-2008; Kirkby, Jasper/A-4973-2012; Servoli, Leonello/E-6766-2012; bertucci, bruna/J-5237-2012; Cavallo, Nicola/F-8913-2012; Cerrada, Marcos/J-6934-2014; Josa, Isabel/K-5184-2014; de la Cruz, Begona/K-7552-2014; Vogel, Helmut/N-8882-2014; Ferguson, Thomas/O-3444-2014; Duran, Ignacio/H-7254-2015; Sanchez, Eusebio/H-5228-2015; Rancoita, Pier Giorgio/J-9896-2015; Hoorani, Hafeez/D-1791-2013; Palomares, Carmen/H-7783-2015; Fedin, Oleg/H-6753-2016; Roth, Stefan/J-2757-2016; Di Lodovico, Francesca/L-9109-2016; Yang, Haijun/O-1055-2015; OI Berdugo, Javier/0000-0002-7911-8532; D'Alessandro, Raffaello/0000-0001-7997-0306; Kirkby, Jasper/0000-0003-2341-9069; Servoli, Leonello/0000-0003-1725-9185; Cerrada, Marcos/0000-0003-0112-1691; Vogel, Helmut/0000-0002-6109-3023; Ferguson, Thomas/0000-0001-5822-3731; Sanchez, Eusebio/0000-0002-9646-8198; Rancoita, Pier Giorgio/0000-0002-1990-4283; Palomares, Carmen/0000-0003-4374-9065; Roth, Stefan/0000-0003-3616-2223; Di Lodovico, Francesca/0000-0003-3952-2175; Longo, Egidio/0000-0001-6238-6787; Castellini, Guido/0000-0002-0177-0643; Diemoz, Marcella/0000-0002-3810-8530; Doria, Alessandra/0000-0002-5381-2649; Faccini, Riccardo/0000-0003-2613-5141 NR 51 TC 27 Z9 27 U1 0 U2 7 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 EI 1873-2445 J9 PHYS LETT B JI Phys. Lett. B PD DEC 24 PY 1998 VL 444 IS 3-4 BP 503 EP 515 DI 10.1016/S0370-2693(98)01403-8 PG 13 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 158DJ UT WOS:000078100500037 ER PT J AU Appelhauser, H Bachler, J Bailey, SJ Barna, D Barnby, LS Bartke, J Barton, RA Bialkowska, H Billmeier, A Blyth, CO Bock, R Bormann, C Brady, FP Brockmann, R Brun, R Buncic, P Caines, HL Carr, LD Cebra, D Cooper, GE Cramer, JG Cristinziani, M Csato, P Dunn, J Eckardt, V Eckhardt, F Ferguson, MI Fischer, HG Flierl, D Fodor, Z Foka, P Freund, P Friese, V Fuchs, M Gabler, F Ganz, R Geist, W Gal, J Gazdzicki, M Gladysz, E Grebieszkow, J Gunther, J Harris, JW Hegyi, S Henkel, T Hill, LA Hummler, H Igo, G Irmscher, D Jacobs, P Jones, PG Kadija, K Kolesnikov, VI Konashenok, A Kowalski, M Lasiuk, B Levai, P Liu, F Malakhov, AI Margetis, S Markert, C Melkumov, GL Mock, A Molnar, J Nelson, JM Oldenburg, M Odyniec, G Palla, G Panagiotou, AD Petridis, A Piper, A Porter, RJ Poskanzer, AM Prindle, DJ Puhlhofer, F Rauch, W Reid, JG Renfordt, R Retyk, W Ritter, HG Rohrich, D Roland, C Roland, G Rudolph, H Rybicki, A Sandoval, A Sann, H Semenov, AY Schafer, E Schmischke, D Schmitz, N Schonfelder, S Seyboth, P Seyerlein, J Sikler, F Skrzypczak, E Snellings, R Squier, GTA Stock, R Strobele, H Struck, C Susa, T Szentpetery, I Sziklai, J Toy, M Trainor, TA Trentalange, S Ullrich, T Vassiliou, M Veres, G Vesztergombi, G Vranic, D Wang, F Weerasundara, DD Wenig, S Whitten, C Wienold, T Wood, L Xu, N Yates, TA Zimanyi, J Zhu, XZ Zybert, R AF Appelhauser, H Bachler, J Bailey, SJ Barna, D Barnby, LS Bartke, J Barton, RA Bialkowska, H Billmeier, A Blyth, CO Bock, R Bormann, C Brady, FP Brockmann, R Brun, R Buncic, P Caines, HL Carr, LD Cebra, D Cooper, GE Cramer, JG Cristinziani, M Csato, P Dunn, J Eckardt, V Eckhardt, F Ferguson, MI Fischer, HG Flierl, D Fodor, Z Foka, P Freund, P Friese, V Fuchs, M Gabler, F Ganz, R Geist, W Gal, J Gazdzicki, M Gladysz, E Grebieszkow, J Gunther, J Harris, JW Hegyi, S Henkel, T Hill, LA Hummler, H Igo, G Irmscher, D Jacobs, P Jones, PG Kadija, K Kolesnikov, VI Konashenok, A Kowalski, M Lasiuk, B Levai, P Liu, F Malakhov, AI Margetis, S Markert, C Melkumov, GL Mock, A Molnar, J Nelson, JM Oldenburg, M Odyniec, G Palla, G Panagiotou, AD Petridis, A Piper, A Porter, RJ Poskanzer, AM Prindle, DJ Puhlhofer, F Rauch, W Reid, JG Renfordt, R Retyk, W Ritter, HG Rohrich, D Roland, C Roland, G Rudolph, H Rybicki, A Sandoval, A Sann, H Semenov, AY Schafer, E Schmischke, D Schmitz, N Schonfelder, S Seyboth, P Seyerlein, J Sikler, F Skrzypczak, E Snellings, R Squier, GTA Stock, R Strobele, H Struck, C Susa, T Szentpetery, I Sziklai, J Toy, M Trainor, TA Trentalange, S Ullrich, T Vassiliou, M Veres, G Vesztergombi, G Vranic, D Wang, F Weerasundara, DD Wenig, S Whitten, C Wienold, T Wood, L Xu, N Yates, TA Zimanyi, J Zhu, XZ Zybert, R CA NA49 Collaboration TI Xi and (Xi)over-bar production in 158 GeV/nucleon Pb+Pb collisions SO PHYSICS LETTERS B LA English DT Article ID HEAVY-ION COLLISIONS; QUARK-GLUON PLASMA; STRANGENESS AB We report measurements of Xi(-) and (Xi)over-bar(+) hyperon absolute yields as a function of rapidity in 158 GeV/c Ph + Pb collisions. At midrapidity, dN/dy = 2.29 +/- 0 12 for Xi(-), and 0.52 +/- 0.05 for (Xi)over-bar(+), leading to the ratio of (Xi)over-bar(+)/Xi(-) = 0.23 +/- 0.03. Inverse slope parameters fitted to the measured transverse mass spectra are of the order of T approximate to 300 MeV near mid-rapidity. The estimated total yield of Xi(-) particles in Pb+ Pb central interactions amounts to 7.4 +/- 1.0 per collision. Comparison to Xi(-) production in properly scaled p + p reactions at the same energy reveals a dramatic enhancement (about one order of magnitude) of Xi(-) production in Pb + Pb central collisions over elementary hadron interactions. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Univ Athens, Dept Phys, GR-10679 Athens, Greece. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Birmingham, Birmingham B15 2TT, W Midlands, England. KFKI, Res Inst Particle & Nucl Phys, Budapest, Hungary. CERN, Geneva, Switzerland. Inst Phys Nucl, Krakow, Poland. Gesell Schwerionenforsch Inst Darmstadt, Darmstadt, Germany. Univ Calif Davis, Davis, CA 95616 USA. Joint Inst Nucl Res, Dubna, Russia. Univ Frankfurt, Fachbereich Phys, Frankfurt, Germany. Kent State Univ, Kent, OH 44242 USA. Univ Calif Los Angeles, Los Angeles, CA 90095 USA. Univ Marburg, Fachbereich Phys, Marburg, Germany. Max Planck Inst Phys, D-80805 Munich, Germany. Inst Nucl Studies, PL-00681 Warsaw, Poland. Univ Warsaw, Inst Phys Expt, PL-00325 Warsaw, Poland. Univ Washington, Phys Nucl Lab, Seattle, WA 98195 USA. Yale Univ, New Haven, CT 06520 USA. Rudjer Boskovic Inst, Zagreb, Croatia. RP Appelhauser, H (reprint author), Univ Heidelberg, Inst Phys, Heidelberg, Germany. RI Barnby, Lee/G-2135-2010; Levai, Peter/A-1544-2014; Carr, Lincoln/E-3819-2016 OI Barnby, Lee/0000-0001-7357-9904; Carr, Lincoln/0000-0002-4848-7941 NR 30 TC 53 Z9 53 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 J9 PHYS LETT B JI Phys. Lett. B PD DEC 24 PY 1998 VL 444 IS 3-4 BP 523 EP 530 DI 10.1016/S0370-2693(98)01399-9 PG 8 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 158DJ UT WOS:000078100500039 ER PT J AU Ackerstaff, K Airapetian, A Akopov, N Akushevich, I Amarian, M Aschenauer, EC Avakian, H Avakian, R Avetissian, A Bains, B Barrow, S Baumgarten, C Beckmann, M Belostotski, S Belz, JE Benisch, T Bernreuther, S Bianchi, N Blanchard, S Blouw, J Bottcher, H Borissov, A Brack, J Brauksiepe, S Braun, B Bray, B Brons, S Bruckner, W Brull, A Bruins, EEW Bulten, HJ Cadman, R Capitani, GP Carter, P Chumney, P Cisbani, E Court, GR Dal Piaz, PF Delheij, PPJ De Sanctis, E De Schepper, D Devitsin, E Huberts, PKAD Di Nezza, P Duren, M Dvoredsky, A Elbakian, G Ely, J Emerson, J Fantoni, A Fechtchenko, A Ferstl, M Fick, D Fiedler, K Filippone, BW Fischer, H Fortune, HT Fox, B Frabetti, S Franz, J Frullani, S Funk, MA Gagunashvili, ND Galumian, P Gao, H Garber, Y Garibaldi, F Gavrilov, G Geiger, P Gharibyan, V Gyurjyan, V Golendoukhin, A Graw, G Grebeniouk, O Green, PW Greeniaus, LG Grosshauser, C Guidal, MG Gute, A Gyurjyan, V Haas, JP Haeberli, W Hansen, JO Hasch, D Hausser, O Heinsius, FH Henderson, R Henkes, T Henoch, M Hertenberger, R Holler, Y Holt, RJ Hoprich, W Ihssen, H Iodice, M Izotov, A Jackson, HE Jgoun, A Jones, C Kaiser, R Kinney, E Kirsch, M Kisselev, A Kitching, P Kobayashi, H Koch, N Konigsmann, K Kolstein, M Kolster, H Korotkov, V Korsch, W Kozlov, V Kramer, LH Krause, B Krivokhijine, VG Kuckes, M Kummell, F Kyle, G Lachnit, W Lorenzon, W Lung, A Makins, NCR Manaenkov, SI Martens, FK Martin, JW Masoli, F Mateos, A McAndrew, M McIlhany, K McKeown, RD Meissner, F Menden, F Mercer, D Metz, A Meyners, N Mikloukho, O Miller, CA Miller, MA Milner, R Mitsyn, V Most, A Mozzetti, R Muccifora, V Nagaitsev, A Naryshkin, Y Nathan, AM Neunreither, F Niczyporuk, M Nowak, WD Nupieri, M Oelwein, P Ogami, H O'Neill, TG Openshaw, R Ouyang, J Owen, B Papavassiliou, V Pate, SF Pitt, M Poolman, HR Potashov, S Potterveld, DH Rakness, G Reali, A Redwine, R Reolon, AR Ristinen, R Rith, K Roloff, H Roper, G Rossi, P Rudnitsky, S Ruh, M Ryckbosch, D Sakemi, Y Savin, I Scarlett, C Schmidt, F Schmitt, H Schnell, G Schuler, KP Schwind, A Seibert, J Shibata, TA Shin, T Shutov, V Simani, MC Simon, A Sinram, K Slavich, P Smythe, WR Sowinski, J Spengos, M Steffens, E Stenger, J Stewart, J Stock, F Stoesslein, U Sutter, M Tallini, H Taroian, S Terkulov, A Thiessen, DM Thomas, E Tipton, B Trudel, A Tytgat, M Urciuoli, GM van Hunen, JJ van de Vyver, R van den Brand, JFJ van der Steenhoven, G Vetterli, MC Vincter, M Visser, J Volk, E Wander, W Welch, TP Williamson, SE Wise, T Woller, K Yoneyama, S Zapfe-Duren, K Zohrabian, H Zurmuhle, R AF Ackerstaff, K Airapetian, A Akopov, N Akushevich, I Amarian, M Aschenauer, EC Avakian, H Avakian, R Avetissian, A Bains, B Barrow, S Baumgarten, C Beckmann, M Belostotski, S Belz, JE Benisch, T Bernreuther, S Bianchi, N Blanchard, S Blouw, J Bottcher, H Borissov, A Brack, J Brauksiepe, S Braun, B Bray, B Brons, S Bruckner, W Brull, A Bruins, EEW Bulten, HJ Cadman, R Capitani, GP Carter, P Chumney, P Cisbani, E Court, GR Dal Piaz, PF Delheij, PPJ De Sanctis, E De Schepper, D Devitsin, E Huberts, PKAD Di Nezza, P Duren, M Dvoredsky, A Elbakian, G Ely, J Emerson, J Fantoni, A Fechtchenko, A Ferstl, M Fick, D Fiedler, K Filippone, BW Fischer, H Fortune, HT Fox, B Frabetti, S Franz, J Frullani, S Funk, MA Gagunashvili, ND Galumian, P Gao, H Garber, Y Garibaldi, F Gavrilov, G Geiger, P Gharibyan, V Gyurjyan, V Golendoukhin, A Graw, G Grebeniouk, O Green, PW Greeniaus, LG Grosshauser, C Guidal, MG Gute, A Gyurjyan, V Haas, JP Haeberli, W Hansen, JO Hasch, D Hausser, O Heinsius, FH Henderson, R Henkes, T Henoch, M Hertenberger, R Holler, Y Holt, RJ Hoprich, W Ihssen, H Iodice, M Izotov, A Jackson, HE Jgoun, A Jones, C Kaiser, R Kinney, E Kirsch, M Kisselev, A Kitching, P Kobayashi, H Koch, N Konigsmann, K Kolstein, M Kolster, H Korotkov, V Korsch, W Kozlov, V Kramer, LH Krause, B Krivokhijine, VG Kuckes, M Kummell, F Kyle, G Lachnit, W Lorenzon, W Lung, A Makins, NCR Manaenkov, SI Martens, FK Martin, JW Masoli, F Mateos, A McAndrew, M McIlhany, K McKeown, RD Meissner, F Menden, F Mercer, D Metz, A Meyners, N Mikloukho, O Miller, CA Miller, MA Milner, R Mitsyn, V Most, A Mozzetti, R Muccifora, V Nagaitsev, A Naryshkin, Y Nathan, AM Neunreither, F Niczyporuk, M Nowak, WD Nupieri, M Oelwein, P Ogami, H O'Neill, TG Openshaw, R Ouyang, J Owen, B Papavassiliou, V Pate, SF Pitt, M Poolman, HR Potashov, S Potterveld, DH Rakness, G Reali, A Redwine, R Reolon, AR Ristinen, R Rith, K Roloff, H Roper, G Rossi, P Rudnitsky, S Ruh, M Ryckbosch, D Sakemi, Y Savin, I Scarlett, C Schmidt, F Schmitt, H Schnell, G Schuler, KP Schwind, A Seibert, J Shibata, TA Shin, T Shutov, V Simani, MC Simon, A Sinram, K Slavich, P Smythe, WR Sowinski, J Spengos, M Steffens, E Stenger, J Stewart, J Stock, F Stoesslein, U Sutter, M Tallini, H Taroian, S Terkulov, A Thiessen, DM Thomas, E Tipton, B Trudel, A Tytgat, M Urciuoli, GM van Hunen, JJ van de Vyver, R van den Brand, JFJ van der Steenhoven, G Vetterli, MC Vincter, M Visser, J Volk, E Wander, W Welch, TP Williamson, SE Wise, T Woller, K Yoneyama, S Zapfe-Duren, K Zohrabian, H Zurmuhle, R CA HERMES Collaboration TI Determination of the deep inelastic contribution to the generalised Gerasimov-Drell-Hearn integral for the proton and neutron SO PHYSICS LETTERS B LA English DT Article ID SPIN STRUCTURE-FUNCTION; STRUCTURE-FUNCTION G(1)(N); RESONANCE REGION; POLARIZED HE-3; PARTON MODEL; SUM-RULES; E-P; SCATTERING; NUCLEON AB The virtual photon absorption cross section differences [alpha(1/2) - alpha(3/2)] for the proton and neutron have been determined from measurements of polarised cross section asymmetries in deep inelastic scattering of 27.5 GeV longitudinally polarised positrons from polarised H-1 and He-3 internal gas targets. The data were collected in the region above the nucleon resonances in the kinematic range v < 23.5 GeV and 0.8 GeV2 < Q(2) < 12 GeV2. For the proton the contribution to the generalised Gerasimov-Drell-Hearn integral was found to be substantial and must be included for an accurate determination of the full integral. Furthermore the data are consistent with a QCD next-to-leading order fit based on previous deep inelastic scattering data. Therefore higher twist effects do not appear significant. (C) 1998 Elsevier Science B.V. All rights reserved. C1 DESY, D-22603 Hamburg, Germany. Univ Alberta, Dept Phys, Edmonton, AB T6G 2J1, Canada. Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. CALTECH, WK Kellogg Radiat Lab, Pasadena, CA 91125 USA. Univ Colorado, Phys Nucl Lab, Boulder, CO 80309 USA. DESY Zeuthen, D-15738 Zeuthen, Germany. Joint Inst Nucl Res, Dubna 141980, Russia. Univ Erlangen Nurnberg, Inst Phys, D-91058 Erlangen, Germany. Univ Ferrara, Dipartmento Fis, I-44100 Ferrara, Italy. Ist Nazl Fis Nucl, I-44100 Ferrara, Italy. Ist Nazl Fis Nucl, Lab Nazl Frascati, I-00044 Frascati, Italy. Florida Int Univ, Dept Phys, Miami, FL 33199 USA. Univ Freiburg, Fak Phys, D-79104 Freiburg, Germany. Univ Ghent, Dept Subatom & Radiat Phys, B-9000 Ghent, Belgium. Max Planck Inst Kernphys, D-69029 Heidelberg, Germany. Univ Illinois, Dept Phys, Urbana, IL 61801 USA. Univ Kentucky, Dept Phys & Astron, Lexington, KY 40506 USA. Univ Liverpool, Dept Phys, Liverpool L69 3BX, Merseyside, England. Univ Wisconsin, Dept Phys, Madison, WI 53706 USA. Univ Marburg, Inst Phys, D-35037 Marburg, Germany. MIT, Nucl Sci Lab, Cambridge, MA 02139 USA. PN Lebedev Phys Inst, Moscow 117924, Russia. Univ Munich, Sekt Phys, D-85748 Garching, Germany. Univ Michigan, Randall Lab Phys, Ann Arbor, MI 48109 USA. New Mexico State Univ, Dept Phys, Las Cruces, NM 88003 USA. NIKHEF H, Natl Inst Kernfys & Hoge Energiefys, NL-1009 DB Amsterdam, Netherlands. Univ Oregon, Eugene, OR 97403 USA. Univ Penn, Philadelphia, PA 19104 USA. Petersburg Nucl Phys Inst, Gatchina 188350, Russia. Ist Nazl Fis Nucl, Sez Sanita, I-00161 Rome, Italy. Ist Super Sanita, Phys Lab, I-00161 Rome, Italy. Simon Fraser Univ, Dept Phys, Burnaby, BC V5A 1S6, Canada. TRIUMF, Vancouver, BC V6T 2A3, Canada. Tokyo Inst Technol, Tokyo 152, Japan. Free Univ Amsterdam, Dept Phys & Astron, NL-1081 HV Amsterdam, Netherlands. Yerevan Phys Inst, Yerevan 375036, Armenia. RP DESY, D-22603 Hamburg, Germany. RI Gao, Haiyan/G-2589-2011; Gavrilov, Gennady/C-6260-2013; Holt, Roy/E-5803-2011; Kozlov, Valentin/M-8000-2015; Terkulov, Adel/M-8581-2015; Cisbani, Evaristo/C-9249-2011 OI Cisbani, Evaristo/0000-0002-6774-8473 NR 46 TC 49 Z9 49 U1 1 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 EI 1873-2445 J9 PHYS LETT B JI Phys. Lett. B PD DEC 24 PY 1998 VL 444 IS 3-4 BP 531 EP 538 DI 10.1016/S0370-2693(98)01396-3 PG 8 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 158DJ UT WOS:000078100500040 ER PT J AU Acciarri, M Adriani, O Aguilar-Benitez, M Ahlen, S Alcaraz, J Alemanni, G Allaby, J Aloisio, A Alviggi, MG Ambrosi, G Anderhub, H Andreev, VP Angelescu, T Anselmo, F Arefiev, A Azemoon, T Aziz, T Bagnaia, P Baksay, L Banerjee, S Banerjee, S Banicz, K Barczyk, A Barillere, R Barone, L Bartalini, P Baschirotto, A Basile, M Battiston, R Bay, A Becattini, F Becker, U Behner, F Berdugo, J Berges, P Bertucci, B Betev, BL Bhattacharya, S Biasini, M Biland, A Bilei, GM Blaising, JJ Blyth, SC Bobbink, GJ Bock, R Bohm, A Boldizsar, L Borgia, B Bourilkov, D Bourquin, M Braccini, S Branson, JG Brigljevic, V Brock, IC Buffini, A Buijs, A Burger, JD Burger, WJ Busenitz, J Button, A Cai, XD Campanelli, M Capell, M Romeo, GC Carlino, G Cartacci, AM Casaus, J Castellini, G Cavallari, F Cavallo, N Cecchi, C Cerrada, M Cesaroni, F Chamizo, M Chang, YH Chaturvedi, UK Chemarin, M Chen, A Chen, G Chen, GM Chen, HF Chen, HS Chereau, X Chiefari, G Chien, CY Cifarelli, L Cindolo, F Civinini, C Clare, I Clare, R Coignet, G Colijn, AP Colino, N Costantini, S Cotorobai, F de la Cruz, B Csilling, A Dai, TS D'Alessandro, R de Asmundis, R Degre, A Deiters, K della Volpe, D Denes, P DeNotaristefani, F Diemoz, M van Dierendonck, D Di Lodovico, F Dionisi, C Dittmar, M Dominguez, A Doria, A Dova, MT Duchesneau, D Duinker, P Duran, I Easo, S El Mamouni, H Engler, A Eppling, FJ Erne, FC Extermann, P Fabre, M Faccini, R Falagan, MA Falciano, S Favara, A Fay, J Fedin, O Felcini, M Ferguson, T Ferroni, F Fesefeldt, H Fiandrini, E Field, JH Filthaut, F Fisher, PH Fisk, I Forconi, G Fredj, L Freudenreich, K Furetta, C Galaktionov, Y Ganguli, SN Garcia-Abia, P Gataullin, M Gau, SS Gentile, S Gheordanescu, N Giagu, S Goldfarb, S Goldstein, J Gong, ZF Gougas, A Gratta, G Gruenewald, MW van Gulik, R Gupta, VK Gurtu, A Gutay, LJ Haas, D Hartmann, B Hasan, A Hatzifotiadou, D Hebbeker, T Herve, A Hidas, P Hirschfelder, J van Hoek, WC Hofer, H Hoorani, H Hou, SR Hu, G Iashvili, I Jin, BN Jones, LW de Jong, P Josa-Mutuberria, I Khan, RA Kamrad, D Kapustinsky, JS Kaur, M Kienzle-Focacci, MN Kim, D Kim, DH Kim, JK Kim, SC Kinnison, WW Kirkby, A Kirkby, D Kirkby, J Kiss, D Kittel, W Klimentov, A Konig, AC Kopp, A Korolko, I Koutsenko, V Kraemer, RW Krenz, W Kunin, A Lacentre, P de Guevara, PL Laktineh, I Landi, G Lapoint, C Lassila-Perini, K Laurikainen, P Lavorato, A Lebeau, M Lebedev, A Lebrun, P Lecomte, P Lecoq, P Le Coultre, P Lee, HJ Le Goff, JM Leiste, R Leonardi, E Levtchenko, P Li, C Lin, CH Lin, WT Linde, FL Lista, L Liu, ZA Lohmann, W Longo, E Lu, W Lu, YS Lubelsmeyer, K Luci, C Luckey, D Luminari, L Lustermann, W Ma, WG Maity, M Majumder, G Malgeri, L Malinin, A Mana, C Mangeol, D Marchesini, P Marian, G Marin, A Martin, JP Marzano, F Massaro, GGG Mazumdar, K McNeil, RR Mele, S Merola, L Meschini, M Metzger, WJ von der Mey, M Migani, D Mihul, A van Mil, AJW Milcent, H Mirabelli, G Mnich, J Molnar, P Monteleoni, B Moore, R Moulik, T Mount, R Muanza, GS Muheim, F Muijs, AJM Nahn, S Napolitano, M Nessi-Tedaldi, F Newman, H Niessen, T Nippe, A Nisati, A Nowak, H Oh, YD Organtini, G Ostonen, R Palomares, C Pandoulas, D Paoletti, S Paolucci, P Park, HK Park, IH Pascale, G Passaleva, G Patricelli, S Paul, T Pauluzzi, M Paus, C Pauss, F Peach, D Pedace, M Pei, YJ Pensotti, S Perret-Gallix, D Petersen, B Petrak, S Pevsner, A Piccolo, D Pieri, M Piroue, PA Pistolesi, E Plyaskin, V Pohl, M Pojidaev, V Postema, H Pothier, J Produit, N Prokofiev, D Quartieri, J Rahal-Callot, G Raja, N Rancoita, PG Rattaggi, M Raven, G Razis, P Ren, D Rescigno, M Reucroft, S van Rhee, T Riemann, S Riles, K Robohm, A Rodin, J Roe, BP Romero, L Rosier-Lees, S Roth, S Rubio, JA Ruschmeier, D Rykaczewski, H Sakar, S Salicio, J Sanchez, E Sanders, MP Sarakinos, ME Schafer, C Schegelsky, V Schmidt-Kaerst, S Schmitz, D Scholz, N Schopper, H Schotanus, DJ Schwenke, J Schwering, G Sciacca, C Sciarrino, D Servoli, L Shevchenko, S Shivarov, N Shoutko, V Shukla, J Shumilov, E Shvorob, A Siedenburg, T Son, D Smith, B Spillantini, P Steuer, M Strickland, DP Stone, A Stone, H Stoyanov, B Straessner, A Sudhakar, K Sultanov, G Sun, LZ Susinno, GF Suter, H Swain, JD Szillasi, Z Tang, XW Tauscher, L Taylor, L Timmermans, C Ting, SCC Ting, SM Tonwar, SC Toth, J Tully, C Tung, KL Uchida, Y Ulbricht, J Valente, E Vesztergombi, G Vetlitsky, I Viertel, G Villa, S Vivargent, M Vlachos, S Vogel, H Vogt, H Vorobiev, I Vorobyov, AA Vorvolakos, A Wadhwa, M Wallraff, W Wang, JC Wang, XL Wang, ZM Weber, A Wu, SX Wynhoff, S Xu, J Xu, ZZ Yang, BZ Yang, CG Yang, HJ Yang, M Ye, JB Yeh, SC You, JM Zalite, A Zalite, Y Zemp, P Zeng, Y Zhang, ZP Zhou, B Zhu, GY Zhu, RY Zichichi, A Ziegler, F Zilizi, G AF Acciarri, M Adriani, O Aguilar-Benitez, M Ahlen, S Alcaraz, J Alemanni, G Allaby, J Aloisio, A Alviggi, MG Ambrosi, G Anderhub, H Andreev, VP Angelescu, T Anselmo, F Arefiev, A Azemoon, T Aziz, T Bagnaia, P Baksay, L Banerjee, S Banerjee, S Banicz, K Barczyk, A Barillere, R Barone, L Bartalini, P Baschirotto, A Basile, M Battiston, R Bay, A Becattini, F Becker, U Behner, F Berdugo, J Berges, P Bertucci, B Betev, BL Bhattacharya, S Biasini, M Biland, A Bilei, GM Blaising, JJ Blyth, SC Bobbink, GJ Bock, R Bohm, A Boldizsar, L Borgia, B Bourilkov, D Bourquin, M Braccini, S Branson, JG Brigljevic, V Brock, IC Buffini, A Buijs, A Burger, JD Burger, WJ Busenitz, J Button, A Cai, XD Campanelli, M Capell, M Romeo, GC Carlino, G Cartacci, AM Casaus, J Castellini, G Cavallari, F Cavallo, N Cecchi, C Cerrada, M Cesaroni, F Chamizo, M Chang, YH Chaturvedi, UK Chemarin, M Chen, A Chen, G Chen, GM Chen, HF Chen, HS Chereau, X Chiefari, G Chien, CY Cifarelli, L Cindolo, F Civinini, C Clare, I Clare, R Coignet, G Colijn, AP Colino, N Costantini, S Cotorobai, F de la Cruz, B Csilling, A Dai, TS D'Alessandro, R de Asmundis, R Degre, A Deiters, K della Volpe, D Denes, P DeNotaristefani, F Diemoz, M van Dierendonck, D Di Lodovico, F Dionisi, C Dittmar, M Dominguez, A Doria, A Dova, MT Duchesneau, D Duinker, P Duran, I Easo, S El Mamouni, H Engler, A Eppling, FJ Erne, FC Extermann, P Fabre, M Faccini, R Falagan, MA Falciano, S Favara, A Fay, J Fedin, O Felcini, M Ferguson, T Ferroni, F Fesefeldt, H Fiandrini, E Field, JH Filthaut, F Fisher, PH Fisk, I Forconi, G Fredj, L Freudenreich, K Furetta, C Galaktionov, Y Ganguli, SN Garcia-Abia, P Gataullin, M Gau, SS Gentile, S Gheordanescu, N Giagu, S Goldfarb, S Goldstein, J Gong, ZF Gougas, A Gratta, G Gruenewald, MW van Gulik, R Gupta, VK Gurtu, A Gutay, LJ Haas, D Hartmann, B Hasan, A Hatzifotiadou, D Hebbeker, T Herve, A Hidas, P Hirschfelder, J van Hoek, WC Hofer, H Hoorani, H Hou, SR Hu, G Iashvili, I Jin, BN Jones, LW de Jong, P Josa-Mutuberria, I Khan, RA Kamrad, D Kapustinsky, JS Kaur, M Kienzle-Focacci, MN Kim, D Kim, DH Kim, JK Kim, SC Kinnison, WW Kirkby, A Kirkby, D Kirkby, J Kiss, D Kittel, W Klimentov, A Konig, AC Kopp, A Korolko, I Koutsenko, V Kraemer, RW Krenz, W Kunin, A Lacentre, P de Guevara, PL Laktineh, I Landi, G Lapoint, C Lassila-Perini, K Laurikainen, P Lavorato, A Lebeau, M Lebedev, A Lebrun, P Lecomte, P Lecoq, P Le Coultre, P Lee, HJ Le Goff, JM Leiste, R Leonardi, E Levtchenko, P Li, C Lin, CH Lin, WT Linde, FL Lista, L Liu, ZA Lohmann, W Longo, E Lu, W Lu, YS Lubelsmeyer, K Luci, C Luckey, D Luminari, L Lustermann, W Ma, WG Maity, M Majumder, G Malgeri, L Malinin, A Mana, C Mangeol, D Marchesini, P Marian, G Marin, A Martin, JP Marzano, F Massaro, GGG Mazumdar, K McNeil, RR Mele, S Merola, L Meschini, M Metzger, WJ von der Mey, M Migani, D Mihul, A van Mil, AJW Milcent, H Mirabelli, G Mnich, J Molnar, P Monteleoni, B Moore, R Moulik, T Mount, R Muanza, GS Muheim, F Muijs, AJM Nahn, S Napolitano, M Nessi-Tedaldi, F Newman, H Niessen, T Nippe, A Nisati, A Nowak, H Oh, YD Organtini, G Ostonen, R Palomares, C Pandoulas, D Paoletti, S Paolucci, P Park, HK Park, IH Pascale, G Passaleva, G Patricelli, S Paul, T Pauluzzi, M Paus, C Pauss, F Peach, D Pedace, M Pei, YJ Pensotti, S Perret-Gallix, D Petersen, B Petrak, S Pevsner, A Piccolo, D Pieri, M Piroue, PA Pistolesi, E Plyaskin, V Pohl, M Pojidaev, V Postema, H Pothier, J Produit, N Prokofiev, D Quartieri, J Rahal-Callot, G Raja, N Rancoita, PG Rattaggi, M Raven, G Razis, P Ren, D Rescigno, M Reucroft, S van Rhee, T Riemann, S Riles, K Robohm, A Rodin, J Roe, BP Romero, L Rosier-Lees, S Roth, S Rubio, JA Ruschmeier, D Rykaczewski, H Sakar, S Salicio, J Sanchez, E Sanders, MP Sarakinos, ME Schafer, C Schegelsky, V Schmidt-Kaerst, S Schmitz, D Scholz, N Schopper, H Schotanus, DJ Schwenke, J Schwering, G Sciacca, C Sciarrino, D Servoli, L Shevchenko, S Shivarov, N Shoutko, V Shukla, J Shumilov, E Shvorob, A Siedenburg, T Son, D Smith, B Spillantini, P Steuer, M Strickland, DP Stone, A Stone, H Stoyanov, B Straessner, A Sudhakar, K Sultanov, G Sun, LZ Susinno, GF Suter, H Swain, JD Szillasi, Z Tang, XW Tauscher, L Taylor, L Timmermans, C Ting, SCC Ting, SM Tonwar, SC Toth, J Tully, C Tung, KL Uchida, Y Ulbricht, J Valente, E Vesztergombi, G Vetlitsky, I Viertel, G Villa, S Vivargent, M Vlachos, S Vogel, H Vogt, H Vorobiev, I Vorobyov, AA Vorvolakos, A Wadhwa, M Wallraff, W Wang, JC Wang, XL Wang, ZM Weber, A Wu, SX Wynhoff, S Xu, J Xu, ZZ Yang, BZ Yang, CG Yang, HJ Yang, M Ye, JB Yeh, SC You, JM Zalite, A Zalite, Y Zemp, P Zeng, Y Zhang, ZP Zhou, B Zhu, GY Zhu, RY Zichichi, A Ziegler, F Zilizi, G CA L3 Collaboration TI QCD results from studies of hadronic events produced in e(+)e(-) annihilations at root s = 183 GeV SO PHYSICS LETTERS B LA English DT Article ID CHARGED-PARTICLE MULTIPLICITIES; W-PAIR PRODUCTION; LUND MONTE-CARLO; E+E ANNIHILATION; L3 EXPERIMENT; ORDER QCD; JET FRAGMENTATION; ROOT-S=130 GEV; Z0 RESONANCE; Z-DECAYS AB We present results obtained from a study of the structure of hadronic events recorded by the L3 detector at a centre-of-mass energy of 183 GeV. The data sample corresponds to an integrated luminosity of 55.3 pb(-1). The distributions of event shape variables and the energy dependence of their mean values are measured. From a comparison with resummed O(alpha(s)(2)) QCD calculations, we determine the strong coupling constant alpha(s) (183 GeV) = 0.1086 +/- 0.0026(exp) +/- 0.0054(th). The charged particle multiplicity distribution and momentum spectrum are studied and the energy dependence of the peak position of the xi(= - ln x(p)) distribution is compared with lower energy measurements and QCD expectations. (C) 1998 Elsevier Science B.V. C1 Ist Nazl Fis Nucl, Sez Milano, I-20133 Milan, Italy. Rhein Westfal TH Aachen, Inst Phys 1, D-52056 Aachen, Germany. Rhein Westfal TH Aachen, Inst Phys 3, D-52056 Aachen, Germany. NIKHEF H, Natl Inst High Energy Phys, NL-1009 DB Amsterdam, Netherlands. Univ Amsterdam, NL-1009 DB Amsterdam, Netherlands. Univ Michigan, Ann Arbor, MI 48109 USA. CNRS, IN2P3, LAPP, Lab Annecy Le Vieux Phys Particules, F-74941 Annecy Le Vieux, France. Johns Hopkins Univ, Baltimore, MD 21218 USA. Univ Basel, Inst Phys, CH-4056 Basel, Switzerland. Louisiana State Univ, Baton Rouge, LA 70803 USA. Inst High Energy Phys, Beijing 100039, Peoples R China. Humboldt Univ, D-10099 Berlin, Germany. Univ Bologna, I-40126 Bologna, Italy. Ist Nazl Fis Nucl, Sez Bologna, I-40126 Bologna, Italy. Tata Inst Fundamental Res, Bombay 400005, Maharashtra, India. Boston Univ, Boston, MA 02215 USA. Northeastern Univ, Boston, MA 02115 USA. Inst Atom Phys, R-76900 Bucharest, Romania. Univ Bucharest, R-76900 Bucharest, Romania. Hungarian Acad Sci, Cent Res Inst Phys, H-1525 Budapest 114, Hungary. MIT, Cambridge, MA 02139 USA. Ist Nazl Fis Nucl, Sez Firenze, I-50125 Florence, Italy. Univ Florence, I-50125 Florence, Italy. CERN, European Lab Particle Phys, CH-1211 Geneva 23, Switzerland. World Lab, FBLJA Project, CH-1211 Geneva 23, Switzerland. Univ Geneva, CH-1211 Geneva 4, Switzerland. Chinese Univ Sci & Technol, USTC, Hefei 230029, Anhui, Peoples R China. Res Inst High Energy Phys, SEFT, SF-00014 Helsinki, Finland. Univ Lausanne, CH-1015 Lausanne, Switzerland. Ist Nazl Fis Nucl, Sez Lecce, I-73100 Lecce, Italy. Univ Lecce, I-73100 Lecce, Italy. Los Alamos Natl Lab, Los Alamos, NM 87544 USA. Univ Lyon 1, Inst Phys Nucl Lyon, IN2P3, CNRS, F-69622 Villeurbanne, France. CIEMAT, Ctr Invest Energet Medioambientales & Tecnol, E-28040 Madrid, Spain. ITEP, Inst Theoret & Expt Phys, Moscow, Russia. Ist Nazl Fis Nucl, Sez Napoli, I-80125 Naples, Italy. Univ Naples Federico II, I-80125 Naples, Italy. Univ Cyprus, Dept Nat Sci, Nicosia, Cyprus. Catholic Univ Nijmegen, NL-6525 ED Nijmegen, Netherlands. Natl Inst Nucl Phys & High Energy Phys, NL-6525 ED Nijmegen, Netherlands. CALTECH, Pasadena, CA 91125 USA. Ist Nazl Fis Nucl, Sez Perugia, I-06100 Perugia, Italy. Univ Perugia, I-06100 Perugia, Italy. Carnegie Mellon Univ, Pittsburgh, PA 15213 USA. Princeton Univ, Princeton, NJ 08544 USA. Univ Roma La Sapienza, I-00185 Rome, Italy. Ist Nazl Fis Nucl, Sez Roma, I-00185 Rome, Italy. Inst Phys Nucl, St Petersburg, Russia. Univ Salerno, I-84100 Salerno, Italy. Ist Nazl Fis Nucl, I-84100 Salerno, Italy. Univ Calif San Diego, La Jolla, CA 92093 USA. Univ Santiago, Dept Fis Particulas Elementales, E-15706 Santiago De Compostela, Spain. Bulgarian Acad Sci, Cent Lab Mechatron & Instrumentat, BU-1113 Sofia, Bulgaria. Korea Adv Inst Sci & Technol, Ctr High Energy Phys, Taejon 305701, South Korea. Univ Alabama, Tuscaloosa, AL 35486 USA. Univ Utrecht, NL-3584 CB Utrecht, Netherlands. NIKHEF H, NL-3584 CB Utrecht, Netherlands. Purdue Univ, W Lafayette, IN 47907 USA. Paul Scherrer Inst, CH-5232 Villigen, Switzerland. DESY, Inst Hochenergiephys, D-15738 Zeuthen, Germany. Swiss Fed Inst Technol, CH-8093 Zurich, Switzerland. Univ Hamburg, D-22761 Hamburg, Germany. Natl Cent Univ, Chungli 32054, Taiwan. Natl Tsing Hua Univ, Dept Phys, Hsinchu, Taiwan. RP Ist Nazl Fis Nucl, Sez Milano, Via Celoria 16, I-20133 Milan, Italy. RI Sanchez, Eusebio/H-5228-2015; Duran, Ignacio/H-7254-2015; Rancoita, Pier Giorgio/J-9896-2015; Hoorani, Hafeez/D-1791-2013; Palomares, Carmen/H-7783-2015; Fedin, Oleg/H-6753-2016; Roth, Stefan/J-2757-2016; Di Lodovico, Francesca/L-9109-2016; Yang, Haijun/O-1055-2015; Ferguson, Thomas/O-3444-2014; Fiandrini, Emanuele/C-4549-2008; Berdugo, Javier/A-2858-2015; D'Alessandro, Raffaello/F-5897-2015; Lista, Luca/C-5719-2008; Kirkby, Jasper/A-4973-2012; Servoli, Leonello/E-6766-2012; bertucci, bruna/J-5237-2012; Cavallo, Nicola/F-8913-2012; Cerrada, Marcos/J-6934-2014; de la Cruz, Begona/K-7552-2014; Josa, Isabel/K-5184-2014; Vogel, Helmut/N-8882-2014 OI Sanchez, Eusebio/0000-0002-9646-8198; Rancoita, Pier Giorgio/0000-0002-1990-4283; Palomares, Carmen/0000-0003-4374-9065; Roth, Stefan/0000-0003-3616-2223; Di Lodovico, Francesca/0000-0003-3952-2175; Castellini, Guido/0000-0002-0177-0643; Ferguson, Thomas/0000-0001-5822-3731; Berdugo, Javier/0000-0002-7911-8532; D'Alessandro, Raffaello/0000-0001-7997-0306; Kirkby, Jasper/0000-0003-2341-9069; Servoli, Leonello/0000-0003-1725-9185; Cerrada, Marcos/0000-0003-0112-1691; Vogel, Helmut/0000-0002-6109-3023 NR 85 TC 46 Z9 46 U1 0 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 EI 1873-2445 J9 PHYS LETT B JI Phys. Lett. B PD DEC 24 PY 1998 VL 444 IS 3-4 BP 569 EP 582 DI 10.1016/S0370-2693(98)01404-X PG 14 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 158DJ UT WOS:000078100500044 ER PT J AU Cheng, TY Brunschwig, BS Bullock, RM AF Cheng, TY Brunschwig, BS Bullock, RM TI Hydride transfer reactions of transition metal hydrides: Kinetic hydricity of metal carbonyl hydrides SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID ORGANOMETALLIC LEWIS-ACIDS; RHENIUM ALKYL COMPLEXES; M = CR; ELECTRON-TRANSFER; LOW-TEMPERATURE; CARBENIUM IONS; NAD+ ANALOGS; CYCLOPENTADIENYL COMPLEXES; ELECTROCHEMICAL OXIDATION; ALPHA-CYCLOPROPYLSTYRENE AB Hydride transfer from neutral transition metal hydrides (MH) to Ph3C+BF4- gives M-FBF3 and Ph3CH. The rate law -d[Ph3C+BF4-]/dt = k[Ph3C+BF4-][MH] was established from kinetic measurements using stopped-flow methods. Second-order rate constants determined in CH2Cl2 solution at 25 degrees C range from k(H)- = 7.2 x 10(-1) M-1 s(-1) to k(H)- = 4.6 x 10(6) M-1 s(-1). The order of increasing kinetic hydricity is (C5H4-CO2Me)(CO)(3)WH < (CO)(5)MnH < Cp*(CO)(3)CrH < Cp(CO)(3)WH < HSiEt3 < cis-(CO)(4)(PCy3)MnH < cis-(CO)(4)(PPh3)MnH < (C5H4Me)(CO)(3)WH < Cp(CO)(3)MoH < Cp*(CO)(3)WH < (indenyl)(CO)(3)WH < (CO)(5)ReH < Cp*(CO)(3)MoH < cis-(CO)(4)(PPh3)ReH < Cp(NO)(2)WH < trans-Cp(CO)(2)(PCy3)MoH < trans-Cp(CO)(2)-(PPh3)MoH < trans-Cp(CO)(2)(PMe3)MoH (Cp = eta(5)-C5H5, Cp* = eta(5)-C5Me5, Cy = cyclohexyl). Ranges of activation parameters for hydride transfer from trans-Cp(CO)(2)(PMe3)MoH, trans-Cp(CO)(2)(PCy3)MoH, cis-(CO)(4)(PPh3)ReH, and Cp*(CO)(3)MoH are Delta H double dagger = 3.0-5.9 kcal mol(-1) and Delta S double dagger = -18 to -24 cal K-1 mol(-1). The rate constant for hydride transfer (k(H)-) from cis-Cp(CO)(2)(PCy3)MoH at -55 degrees C is 3 orders of magnitude lower than that for trans-Cp(C0)2(PCy3)MoH. Phosphine substitution for CO generally enhances the kinetic hydricity, with trans-Cp(CO)(2)(PMe3)MoH being 10(4) times as reactive as Cp(CO)(3)MoH. The electronic effect of phosphine substitution is attenuated by steric factors when the phosphine is cis to the metal hydride. The hydride transfer kinetics reported here are interpreted to be single-step hydride transfers, rather than a multiple-step mechanism involving an initial electron transfer followed by hydrogen atom transfer. A distinction is made between hydricity and nucleophilicity of metal hydrides. C1 Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. RP Bullock, RM (reprint author), Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. RI Brunschwig, Bruce/G-4249-2011; Bullock, R. Morris/L-6802-2016 OI Bullock, R. Morris/0000-0001-6306-4851 NR 99 TC 89 Z9 89 U1 1 U2 28 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0002-7863 J9 J AM CHEM SOC JI J. Am. Chem. Soc. PD DEC 23 PY 1998 VL 120 IS 50 BP 13121 EP 13137 DI 10.1021/ja9820036 PG 17 WC Chemistry, Multidisciplinary SC Chemistry GA 151XY UT WOS:000077747000014 ER PT J AU Krueger, JK Bishop, NA Blumenthal, DK Zhi, G Beckingham, K Stull, JT Trewhella, J AF Krueger, JK Bishop, NA Blumenthal, DK Zhi, G Beckingham, K Stull, JT Trewhella, J TI Calmodulin binding to myosin light chain kinase begins at substoichiometric Ca2+ concentrations: A small-angle scattering study of binding and conformational transitions SO BIOCHEMISTRY LA English DT Article ID X-RAY-SCATTERING; CYCLIC-NUCLEOTIDE PHOSPHODIESTERASE; CALCIUM-BINDING; TROPONIN-C; INTRASTERIC REGULATION; QUANTITATIVE-ANALYSIS; PHOSPHORYLASE-KINASE; ALPHA-LACTALBUMIN; PEPTIDE COMPLEX; PROTEIN-KINASES AB We have used small-angle scattering to study the calcium dependence of the interactions between calmodulin (CaM) and skeletal muscle myosin light chain kinase (MLCK), as well as the conformations of the complexes that form. Scattering data were measured from equimolar mixtures of a functional MLCK and CaM or a mutated CaM (B12QCaM) incompetent to bind Ca2+ in its N-terminal domain, with increasing Ca2+ concentrations. To evaluate differences between CaM-enzyme versus CaM-peptide interactions, similar Ca2+ titration experiments were performed using synthetic peptides based on the CaM-binding sequence from MLCK (MLCK-I), Our data show there are different determinants for CaM binding the isolated peptide sequence compared to CaM binding to the same sequences within the enzyme. For example, binding of either CaM or B12QCaM to the MLCK-I peptide is observed even in the presence of EGTA, whereas binding of CaM to the enzyme requires Ca2+. The peptide studies also show that the conformational collapse of CaM requires both the N and C domains of CaM to be competent for Ca2+ binding as well as interactions with each end of MLCK-I, and it occurs at similar to 2 mol of Ca2+/mol of CaM. We show that CaM binding to the MLCK enzyme begins at substoichiometric concentrations of Ca2+ (less than or equal to 2 mol of Ca2+/mol of CaM), but that the final compact structure of CaM with the enzyme requires saturating Ca2+. in addition, MLCK enzyme does bind to 2Ca(2+). B12QCaM, although this complex is more extended than the complex with native CaM, Our results support the hypothesis that CaM regulation of MLCK involves an initial binding step at less than saturating Ca2+ concentrations and a subsequent activation step at higher Ca2+ concentrations. C1 Univ Calif Los Alamos Natl Lab, Chem Sci & Technol Div, Los Alamos, NM 87545 USA. Rice Univ, Dept Biochem & Cell Biol, Houston, TX 77251 USA. Univ Texas, SW Med Ctr, Dept Physiol, Dallas, TX 75235 USA. Univ Utah, Dept Pharmacol & Toxicol, Salt Lake City, UT 84112 USA. RP Trewhella, J (reprint author), Univ Calif Los Alamos Natl Lab, Chem Sci & Technol Div, Mail Stop G758, Los Alamos, NM 87545 USA. RI Krueger, Joanna/A-3110-2011; OI Trewhella, Jill/0000-0002-8555-6766; Blumenthal, Donald/0000-0002-8614-1167 FU NHLBI NIH HHS [HL26043]; NIGMS NIH HHS [GM40528, GM49155] NR 53 TC 33 Z9 35 U1 0 U2 5 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0006-2960 J9 BIOCHEMISTRY-US JI Biochemistry PD DEC 22 PY 1998 VL 37 IS 51 BP 17810 EP 17817 DI 10.1021/bi981656w PG 8 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 153TH UT WOS:000077848400020 PM 9922147 ER PT J AU Zhan, CG Chipman, DM AF Zhan, CG Chipman, DM TI Cavity size in reaction field theory SO JOURNAL OF CHEMICAL PHYSICS LA English DT Review ID MOLECULAR-ORBITAL METHODS; POLARIZABLE CONTINUUM MODEL; SOLVATION FREE-ENERGIES; BOUNDARY-ELEMENT METHOD; AB-INITIO; CHARGE-DISTRIBUTION; CONFORMATIONAL-ANALYSIS; DIELECTRIC CONTINUUM; ELECTRONIC-STRUCTURE; BASIS-SETS AB The optimum size of the cavity accommodating a solute in the reaction field theory of solvation is considered by empirical calibration of the results of electronic structure calculations against experiment. To isolate the long range electrostatic free energy contributions treated by reaction field theory from the many other short range contributions not explicitly considered, computational results are compared to experimental determinations of conformational free energy differences in polar solutes having two or more stable or metastable isomers. When the cavity shape is defined by a solute electronic isodensity contour, it is found that the best overall agreement with experiment is obtained with a cavity size corresponding to the 0.001 a.u. contour. (C) 1998 American Institute of Physics. [S0021-9606(98)00348-1]. C1 Univ Notre Dame, Radiat Lab, Notre Dame, IN 46556 USA. Univ Notre Dame, Dept Chem & Biochem, Notre Dame, IN 46556 USA. RP Zhan, CG (reprint author), Battelle NW, Pacific NW Natl Lab, Mail Stop K2-21, Richland, WA 99352 USA. RI Chipman, Daniel/C-7704-2015 OI Chipman, Daniel/0000-0002-9992-6684 NR 115 TC 100 Z9 102 U1 0 U2 5 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD DEC 22 PY 1998 VL 109 IS 24 BP 10543 EP 10558 DI 10.1063/1.477755 PG 16 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 148QB UT WOS:000077542400002 ER PT J AU Knickelbein, MB Koretsky, GM Jackson, KA Pederson, MR Hajnal, Z AF Knickelbein, MB Koretsky, GM Jackson, KA Pederson, MR Hajnal, Z TI Hydrogenated and deuterated iron clusters: Infrared spectra and density functional calculations SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID TRANSITION-METAL CLUSTERS; GAS VANDERWAALS COMPLEXES; NICKEL CLUSTERS; IONIZATION-POTENTIALS; ELECTRONIC-STRUCTURE; SURFACE-REACTIONS; CHEMICAL PROBES; FE-N; CHEMISORPTION; SPECTROSCOPY AB Iron clusters react sequentially with hydrogen molecules to form multiply hydrogenated products. The increases in cluster ionization potential upon reaction verify that hydrogen chemisorbs dissociatively to form iron cluster-hydride complexes, FenHm. At low source temperatures, the cluster-hydride complexes take up additional hydrogen molecules which are shown to be physisorbed onto the underlying FenHm complexes to form FenHm(H-2)(p) species. The infrared spectra of FenHm and FenDm (n=9-20) were obtained by the photodissociation action spectroscopic method in which depletion of the FenHm(H-2)(p) and FenDm(D-2)(p) species was the signature of absorption. The spectra, recorded in the 885-1090 cm(-1) region, consist of several overlapping bands, each approximately 20 cm(-1) in width. The dissimilarity of each FenHm(H-2)(p) spectrum with the corresponding FenDm(D-2)(p) spectrum indicates that the carrier involves hydrogen and is not merely due to absorption by the underlying iron cluster. Density functional calculations were performed on model complexes, Fe13H14 and Fe13D14, the iron portion of which was assumed to have T-h symmetry. The infrared-active vibrational frequencies involving hydrogen bending and deuterium stretching are predicted to lie within the experimental frequency range of the experiment, well removed from the skeletal modes of the underlying iron cluster. The complexity of the observed spectra as compared to simulations based on the assumed thigh-symmetry) model imply that the experimentally produced complexes possess low symmetry. (C) 1998 American Institute of Physics. [S0021-9606(98)01148-9]. C1 Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. Cent Michigan Univ, Dept Phys, Mt Pleasant, MI 48859 USA. USN, Res Lab, Complex Syst Theory Branch, Washington, DC 20375 USA. Univ GH Paderborn, D-33095 Paderborn, Germany. RP Knickelbein, MB (reprint author), Argonne Natl Lab, Div Chem, 9700 S Cass Ave, Argonne, IL 60439 USA. RI HAJNAL, Zoltan/B-6385-2008; OI HAJNAL, Zoltan/0000-0003-1758-4754; Jackson, Koblar/0000-0002-5342-7978 NR 45 TC 39 Z9 40 U1 2 U2 10 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-9606 EI 1089-7690 J9 J CHEM PHYS JI J. Chem. Phys. PD DEC 22 PY 1998 VL 109 IS 24 BP 10692 EP 10700 DI 10.1063/1.477767 PG 9 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 148QB UT WOS:000077542400017 ER PT J AU Lenzer, T Furlanetto, MR Asmis, KR Neumark, DM AF Lenzer, T Furlanetto, MR Asmis, KR Neumark, DM TI Zero electron kinetic energy and photoelectron spectroscopy of the XeI- anion SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID THRESHOLD PHOTODETACHMENT SPECTROSCOPY; BOUND-FREE EMISSION; NOBLE-GAS HALIDES; INTERACTION POTENTIALS; DISPERSION COEFFICIENTS; EXCITED-STATES; IONIC STATES; SHELL ATOMS; TRANSITION; COMPLEXES AB The XeI- anion and the corresponding neutral X1/2, I3/2, and II1/2 electronic states have been studied by means of zero electron kinetic energy (ZEKE) and photoelectron spectroscopy. The ZEKE spectra show rich and well-resolved progressions in the low-frequency vibrations of the anion and the neutral van der Waals complexes. From our spectroscopic data we construct model potentials for the anion and three neutral states, which are compared to previously obtained potential functions for this system. The intensity of the I3/2<--anion transitions relative to the X1/2 <--anion transitions in the XeI- ZEKE spectrum is considerably lower than expected from a Franck-Condon simulation based on the model potentials. Comparison with the photoelectron spectrum of XeI- indicates this is due to a small s-wave partial cross section for photodetachment to the I3/2 state. (C) 1998 American Institute of Physics. [S0021-9606(98)00148-2]. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA. RP Lenzer, T (reprint author), Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. RI Asmis, Knut/N-5408-2014; Neumark, Daniel/B-9551-2009 OI Asmis, Knut/0000-0001-6297-5856; Neumark, Daniel/0000-0002-3762-9473 NR 64 TC 39 Z9 40 U1 0 U2 4 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD DEC 22 PY 1998 VL 109 IS 24 BP 10754 EP 10766 DI 10.1063/1.477774 PG 13 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 148QB UT WOS:000077542400024 ER PT J AU Wu, JZ Bratko, D Prausnitz, JM AF Wu, JZ Bratko, D Prausnitz, JM TI Interaction between like-charged colloidal spheres in electrolyte solutions SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article ID ELECTROSTATIC ATTRACTION; HYPERNETTED CHAIN; INTEGRAL-EQUATION; PARTICLES; FORCES; COUNTERIONS AB How colloidal particles interact with each other is one of the key issues that determines our ability to interpret experimental results for phase transitions in colloidal dispersions and our ability to apply colloid science to various industrial processes. The long-accepted theories for answering this question have been challenged by results from recent experiments. Herein we show from Monte-Carlo simulations that there is a short-range attractive force between identical macroions in electrolyte solutions containing divalent counterions. Complementing some recent and related results by others, we present strong evidence of attraction between a pair of spherical macroions in the presence of added salt ions for the conditions where the interacting macroion pair is not affected by any other macroions that may be in the solution, This attractive force follows from the internal-energy contribution of counterion mediation. Contrary to conventional expectations, for charged macroions in an electrolyte solution, the entropic force is repulsive at most solution conditions because of localization of small ions in the vicinity of macroions. Both Derjaguin-Landau-Verwey-Overbeek theory and Sogami-Ise theory fail to describe the attractive interactions found in our simulations; the former predicts only repulsive interaction and the latter predicts a long-range attraction that is too weak and occurs at macroion separations that are too large. Our simulations provide fundamental "data" toward an improved theory for the potential of mean force as required for optimum design of new materials including those containing nanoparticles. C1 Univ Calif Berkeley, Dept Chem Engn, Berkeley, CA 94720 USA. Lawrence Berkeley Natl Lab, Div Chem Sci, Berkeley, CA 94720 USA. RP Prausnitz, JM (reprint author), Univ Calif Berkeley, Dept Chem Engn, Berkeley, CA 94720 USA. EM lindar@cchem.berkeley.edu RI Wu, Jianzhong/I-5164-2013; OI Wu, Jianzhong/0000-0002-4582-5941 NR 35 TC 125 Z9 127 U1 1 U2 25 PU NATL ACAD SCIENCES PI WASHINGTON PA 2101 CONSTITUTION AVE NW, WASHINGTON, DC 20418 USA SN 0027-8424 J9 P NATL ACAD SCI USA JI Proc. Natl. Acad. Sci. U. S. A. PD DEC 22 PY 1998 VL 95 IS 26 BP 15169 EP 15172 DI 10.1073/pnas.95.26.15169 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 150ZV UT WOS:000077697200007 PM 9860940 ER PT J AU Zarembinski, TI Hung, LW Mueller-Dieckmann, HJ Kim, KK Yokota, H Kim, R Kim, SH AF Zarembinski, TI Hung, LW Mueller-Dieckmann, HJ Kim, KK Yokota, H Kim, R Kim, SH TI Structure-based assignment of the biochemical function of a hypothetical protein: A test case of structural genomics SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article ID MACROMOLECULAR STRUCTURES; ANOMALOUS DIFFRACTION; CRYSTAL-STRUCTURE; SEQUENCE; CRYSTALLIZATION; RESOLUTION; REFINEMENT; ARCHAEON; PROGRAM AB Many small bacterial, archaebacterial, and eukaryotic genomes have been sequenced, and the larger eukaryotic genomes are predicted to be completely sequenced within the next decade, In all genomes sequenced to date, a large portion of these organisms' predicted protein coding regions encode polypeptides of unknown biochemical, biophysical, and/or cellular functions, Three-dimensional structures of these proteins may suggest biochemical or biophysical functions. Here we report the crystal structure of one such protein, MJ0577 from a hyperthermophile, Methanococcus jannaschii, at 1.7-Angstrom resolution. The structure contains a hound ATP, suggesting MJ0577 is an ATPase or an ATP-mediated molecular switch, which we confirm by biochemical experiments, Furthermore, the structure reveals different ATP binding motifs that are shared among many homologous hypothetical proteins in this family. This result indicates that structure-based assignment of molecular function is a viable approach for the large-scale biochemical assignment of proteins and for discovering new motifs, a basic premise of structural genomics. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. RP Kim, SH (reprint author), Lawrence Berkeley Natl Lab, Phys Biosci Div, Berkeley, CA 94720 USA. EM shkim@lbl.gov NR 41 TC 215 Z9 225 U1 0 U2 5 PU NATL ACAD SCIENCES PI WASHINGTON PA 2101 CONSTITUTION AVE NW, WASHINGTON, DC 20418 USA SN 0027-8424 J9 P NATL ACAD SCI USA JI Proc. Natl. Acad. Sci. U. S. A. PD DEC 22 PY 1998 VL 95 IS 26 BP 15189 EP 15193 DI 10.1073/pnas.95.26.15189 PG 5 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 150ZV UT WOS:000077697200011 PM 9860944 ER PT J AU Semizarov, D Glesne, D Laouar, A Schiebel, K Huberman, E AF Semizarov, D Glesne, D Laouar, A Schiebel, K Huberman, E TI A lineage-specific protein kinase crucial for myeloid maturation SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article ID PROMYELOCYTIC LEUKEMIA-CELLS; HL-60 CELLS; TERMINAL DIFFERENTIATION; DIMETHYL-SULFOXIDE; RETINOIC ACID; C-BETA; EXPRESSION; RNA; INDUCTION; GENE AB To identify genes involved in macrophage development, we used the differential display technique and compared the gene expression profiles for human myeloid HL-60 leukemia cell lines susceptible and resistant to macrophage maturation. We identified a gene coding for a protein kinase, protein kinase X (PRKX), which was expressed in the maturation-susceptible, but not in the resistant, cell line. The expression of the PRKX gene was found to be induced during monocyte, macrophage, and granulocyte maturation of HL-60 cells. We also studied the expression of the PRKX gene in 12 different human tissues and transformed cell lines and found that, among these tissues and cell types, the PRKX gene is expressed only in blood. Among the blood cell lineages, the PRKX gene is specifically expressed in macrophages and granulocytes. Antisense inhibition of PRKX expression blocked terminal development in both the leukemic HL-60 cells and normal peripheral blood monocytes, implying that PRKX is a key mediator of macrophage and granulocyte maturation. Using the HL-60 cell variant deficient in protein kinase C-beta (PKC-beta) and several stable PKC-beta transfectants, we found that PRKX gene expression is under control of PKC-beta; hence PRKX is likely to act downstream of this PKC isozyme in the same signal transduction pathway leading to macrophage maturation. C1 Argonne Natl Lab, Ctr Mechanist Biol & Biotechnol, Argonne, IL 60439 USA. Univ Heidelberg, Inst Human Genet, D-69120 Heidelberg, Germany. RP Huberman, E (reprint author), Argonne Natl Lab, Ctr Mechanist Biol & Biotechnol, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 41 TC 31 Z9 36 U1 0 U2 0 PU NATL ACAD SCIENCES PI WASHINGTON PA 2101 CONSTITUTION AVE NW, WASHINGTON, DC 20418 USA SN 0027-8424 J9 P NATL ACAD SCI USA JI Proc. Natl. Acad. Sci. U. S. A. PD DEC 22 PY 1998 VL 95 IS 26 BP 15412 EP 15417 DI 10.1073/pnas.95.26.15412 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 150ZV UT WOS:000077697200049 PM 9860982 ER PT J AU Bergeron, N Kotite, L Verges, M Blanche, P Hamilton, RL Krauss, RM Bensadoun, A Havel, RJ AF Bergeron, N Kotite, L Verges, M Blanche, P Hamilton, RL Krauss, RM Bensadoun, A Havel, RJ TI Lamellar lipoproteins uniquely contribute to hyperlipidemia in mice doubly deficient in apolipoprotein E and hepatic lipase SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article DE cholesterol; phospholipids; scavenger receptor B1; endocytosis ID HIGH-DENSITY-LIPOPROTEIN; SCAVENGER RECEPTOR BI; CHYLOMICRON REMNANTS; HDL RECEPTOR; SR-BI; A-I; CHOLESTEROL; METABOLISM; LIVER; HYPERCHOLESTEROLEMIA AB Remnants of triglyceride-rich lipoproteins containing apolipoprotein (apo) B-48 accumulate in apo E-deficient mice, causing pronounced hypercholesterolemia. Mice doubly deficient in apo E and hepatic lipase have more pronounced hypercholesterolemia, even though remnants do not accumulate appreciably in mice deficient in hepatic lipase alone. Here we show that the doubly deficient mice manifest a unique lamellar hyperlipoproteinemia, characterized by vesicular particles 600 Angstrom-1,300 Angstrom in diameter. As seen by negative-staining electron microscopy, these lipoproteins also contain an electron-lucent region adjacent to the vesicle wall, similar to the core of typical lipoproteins. Correlative chemical analysis indicates that the vesicle wall is composed of a 1:1 molar mixture of cholesterol and phospholipids, whereas the electron-lucent region appears to be composed of cholesteryl esters (about 12% of the particle mass), Like the spherical lipoproteins of doubly deficient mice, the vesicular particles contain apo B-48, but they are particularly rich in apo A-IV. We propose that cholesteryl esters are removed from spherical lipoproteins of these mice by scavenger receptor B1, leaving behind polar lipid-rich particles that fuse to form vesicular lipoproteins. Hepatic lipase may prevent such vesicular lipoproteins from accumulating in apo E-deficient mice by hydrolyzing phosphatidyl choline as scavenger receptor B1 removes the cholesteryl esters and by gradual endocytosis of lipoproteins bound to hepatic lipase on the surface of hepatocytes. C1 Univ Calif San Francisco, Cardiovasc Res Inst, San Francisco, CA 94143 USA. Univ Calif San Francisco, Dept Anat, San Francisco, CA 94143 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Cornell Univ, Div Nutr Sci & Biol Sci, Ithaca, NY 14853 USA. RP Havel, RJ (reprint author), Univ Calif San Francisco, Cardiovasc Res Inst, Box 0130, San Francisco, CA 94143 USA. FU NHLBI NIH HHS [HL 14237, HL 14990, HL 18574] NR 38 TC 25 Z9 25 U1 0 U2 1 PU NATL ACAD SCIENCES PI WASHINGTON PA 2101 CONSTITUTION AVE NW, WASHINGTON, DC 20418 USA SN 0027-8424 J9 P NATL ACAD SCI USA JI Proc. Natl. Acad. Sci. U. S. A. PD DEC 22 PY 1998 VL 95 IS 26 BP 15647 EP 15652 DI 10.1073/pnas.95.26.15647 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 150ZV UT WOS:000077697200091 PM 9861024 ER PT J AU Perlin, P Subramanya, SG Mars, DE Kruger, J Shapiro, NA Siegle, H Weber, ER AF Perlin, P Subramanya, SG Mars, DE Kruger, J Shapiro, NA Siegle, H Weber, ER TI Pressure and temperature dependence of the absorption edge of a thick Ga0.92In0.08As0.985N0.015 layer SO APPLIED PHYSICS LETTERS LA English DT Article ID ALLOYS; LUMINESCENCE; GAAS1-XNX AB We have studied the pressure and temperature dependence of the absorption edge of a 4-mu m-thick layer of the alloy Ga0.92In0.08As0.985N0.015. We have measured the hydrostatic pressure coefficient of the energy gap of this alloy to be 51 meV/GPa, which is more than a factor two lower than that of GaAs (116 meV/GPa). This surprisingly large lowering of the pressure coefficient is attributed to the addition of only similar to 1.5% nitrogen. In addition, the temperature-induced shift of the edge is reduced by the presence of nitrogen. We can explain this reduction by the substantial decrease of the dilatation term in the temperature dependence of the energy gap. (C) 1998 American Institute of Physics. [S0003-6951(98)01251-0]. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Hewlett Packard Labs, Palo Alto, CA 94304 USA. RP Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. EM pperlin@ux8.lbl.gov NR 10 TC 70 Z9 70 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 0003-6951 EI 1077-3118 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD DEC 21 PY 1998 VL 73 IS 25 BP 3703 EP 3705 DI 10.1063/1.122869 PG 3 WC Physics, Applied SC Physics GA 146XH UT WOS:000077458200026 ER PT J AU Weldon, MK Collot, M Chabal, YJ Venezia, VC Agarwal, A Haynes, TE Eaglesham, DJ Christman, SB Chaban, EE AF Weldon, MK Collot, M Chabal, YJ Venezia, VC Agarwal, A Haynes, TE Eaglesham, DJ Christman, SB Chaban, EE TI Mechanism of silicon exfoliation induced by hydrogen/helium co-implantation SO APPLIED PHYSICS LETTERS LA English DT Article AB Infrared spectroscopy and secondary ion mass spectrometry are used to elucidate the mechanism by which co-implantation of He with H facilitates the shearing of crystalline Si. By studying different implant conditions, we can separate the relative contributions of damage, internal pressure generation, and chemical passivation to the enhanced exfoliation process. We find that the He acts physically as a source of internal pressure but also in an indirect chemical sense, leading to the reconversion of molecular H-2 to bound Si-H in "VH2-like" defects. We postulate that it is the formation of these hydrogenated defects at the advancing front of the expanding microcavities that enhances the exfoliation process. [S0003-6951(98)01851-8]. C1 AT&T Bell Labs, Lucent Technol, Murray Hill, NJ 07974 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Weldon, MK (reprint author), AT&T Bell Labs, Lucent Technol, 600-700 Mt Ave, Murray Hill, NJ 07974 USA. EM marcus@bell-labs.com RI Chabal, Yves/A-5998-2011; Haynes, Tony/P-8932-2015 OI Chabal, Yves/0000-0002-6435-0347; Haynes, Tony/0000-0003-2871-4745 NR 13 TC 79 Z9 81 U1 0 U2 8 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD DEC 21 PY 1998 VL 73 IS 25 BP 3721 EP 3723 DI 10.1063/1.122875 PG 3 WC Physics, Applied SC Physics GA 146XH UT WOS:000077458200032 ER PT J AU Ade, H Winesett, DA Smith, AP Anders, S Stammler, T Heske, C Slep, D Rafailovich, MH Sokolov, J Stohr, J AF Ade, H Winesett, DA Smith, AP Anders, S Stammler, T Heske, C Slep, D Rafailovich, MH Sokolov, J Stohr, J TI Bulk and surface characterization of a dewetting thin film polymer bilayer SO APPLIED PHYSICS LETTERS LA English DT Article ID X-RAY MICROSCOPY; CHEMICAL CONTRAST; XANES; INTERFACE; DYNAMICS; BLENDS AB We have monitored the progression of the dewetting of a partially brominated polystyrene (PBrS) thin film on top of a polystyrene (PS) thin film with scanning transmission x-ray microscopy (STXM) as well as photoemission electron microscopy (PEEM). We mapped the projected thickness of each constituent polymer species and the total thickness of the film with STXM, while we determined the surface composition with PEEM. Our data show that the PBrS top layer becomes encapsulated during the later stages of dewetting and that atomic force microscopy topographs cannot be utilized to determine the contact angle between PBrS and PS. (C) 1998 American Institute of Ph? sics. [S0003-6951(98)02351-1]. C1 N Carolina State Univ, Dept Phys, Raleigh, NC 27695 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Adv LIght Source, Berkeley, CA 94720 USA. Hilord Chem Corp, Adv Dev & Res, Hauppauge, NY 11788 USA. SUNY Stony Brook, Dept Mat Sci & Engn, Stony Brook, NY 11794 USA. IBM Corp, Almaden Res Ctr, Div Res, San Jose, CA 95120 USA. RP Ade, H (reprint author), N Carolina State Univ, Dept Phys, Raleigh, NC 27695 USA. RI Ade, Harald/E-7471-2011; Raoux, Simone/G-3920-2016 NR 22 TC 50 Z9 50 U1 0 U2 10 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD DEC 21 PY 1998 VL 73 IS 25 BP 3775 EP 3777 DI 10.1063/1.122891 PG 3 WC Physics, Applied SC Physics GA 146XH UT WOS:000077458200050 ER PT J AU Henson, NJ Cheetham, AK Stockenhuber, M Lercher, JA AF Henson, NJ Cheetham, AK Stockenhuber, M Lercher, JA TI Modelling aromatics in siliceous zeolites: a new forcefield from thermochemical studies SO JOURNAL OF THE CHEMICAL SOCIETY-FARADAY TRANSACTIONS LA English DT Article ID MONTE-CARLO SIMULATIONS; MOLECULAR-DYNAMICS; UNCONSTRAINED MINIMIZATION; INTERATOMIC POTENTIALS; FAUJASITE-TYPE; N-ALKANES; H-2 NMR; ADSORPTION; SILICALITE; DIFFUSION AB A new forcefield for the modelling of interactions between aromatics and siliceous zeolites has been derived by fitting to calorimetric data on the sorption of benzene in siliceous faujasite. The calometric measurements suggest a heat of sorption of 55 kJ mol(-1) at densities lower than 22 molecules per unit cell. Monte Carlo docking calculations have been carried out, using the new forcefield, to predict the most favourable binding sites for sorption of benzene in this zeolite. They show a relatively hat potential-energy surface as compared to Na-Y with a wide variety of different mainly low-symmetry binding sites. The sites are to be classified as being either near to 4-rings (58.4 kJ mol(-1)), 6-rings (50.0 kJ mol(-1)) or in the 12-ring window (43.7 kJ mol(-1)). These results are consistent with neutron diffraction measurements on the same system. Molecular dynamics calculations with the new forcefield suggest that two processes contribute to the motion of benzene molecules in the pore system. At low temperatures, the benzene molecules tend to be confined to a single supercage by sliding around the walls. However, at higher temperatures, the molecules have sufficient kinetic energy to move through the 12 ring window into an adjacent supercage. Minimum-energy pathways have also been calculated, based on the docking binding sites, which correlate well with this rationalisation of the transport mechanism. C1 Univ Calif Santa Barbara, Dept Mat, Santa Barbara, CA 93106 USA. Vienna Tech Univ, Inst Phys Chem, A-1060 Vienna, Austria. Univ Twente, Fac Chem Technol, NL-7500 AE Enschede, Netherlands. RP Henson, NJ (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. EM neil.henson@lanl.gov RI Lercher, Johannes/C-1186-2010; STOCKENHUBER, MICHAEL/G-7997-2013 NR 58 TC 23 Z9 23 U1 0 U2 7 PU ROYAL SOC CHEMISTRY PI CAMBRIDGE PA THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD,, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND SN 0956-5000 J9 J CHEM SOC FARADAY T JI J. Chem. Soc.-Faraday Trans. PD DEC 21 PY 1998 VL 94 IS 24 BP 3759 EP 3768 DI 10.1039/a806175k PG 10 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 149YE UT WOS:000077634100035 ER PT J AU Chen, KC Ford, RM Cummings, PT AF Chen, KC Ford, RM Cummings, PT TI Mathematical models for motile bacterial transport in cylindrical tubes SO JOURNAL OF THEORETICAL BIOLOGY LA English DT Article; Proceedings Paper CT Annual Meeting of AIChE CY NOV 11-17, 1996 CL CHICAGO, ILLINOIS SP AIChE ID CHEMOTACTIC CELL-POPULATIONS; ESCHERICHIA-COLI; 3-DIMENSIONAL TRACKING; LIGHT-SCATTERING; POROUS-MEDIA; PORES; CAPILLARY; MIGRATION; COEFFICIENTS; PENETRATION AB Mathematical models considering motile bacterial transport within a geometrically restrictive cylindrical tube were developed. Two macroscopic transport parameters, the random motility coefficient as a self-diffusion coefficient of the cell population and the chemotactic velocity as a chemical-induced velocity, were derived. The three-dimensional cell balance equation was reduced to forms similar to Segel's one-dimensional phenomenological cell balance equations with additional modifications for bacteria-wall interactions. Two conceptually different approaches accounting for such interactions were presented. The first approach parallels treatments in the gas kinetic theory by viewing bacterial interactions with walls as collisions and subsequent diffusive/specular reflections, which led to the Bosanquet formula for the bacterial diffusion coefficient. Based on the experimental observation that bacterial swimming motion is guided by a straight tube, the second approach considered modifications in the bacterial swimming orientation as a consequence of various long-range interactions with the tube surface. A phenomenological turning model capable of aligning bacterial motion along a tube axis was proposed. The model predicts that under the geometrical restriction of a small cylindrical tube, the macroscopic bacterial transport resulting from the proposed turning model can exhibit behavior that ranges from dimensionally reduced diffusion to pure wave propagation, depending on the influence of the tube diameter on the reversal probability in the bacterial swimming motion. Our theoretical model provides explicit equations that explain how such a transition can occur. The predicted results were then qualitatively compared with experimental data from the literature. As a preliminary comparison, we concluded that bacterial transport in cylindrical tubes of diameter 10 mu m remains in the mode of dimensionally reduced diffusion, and shifts to a wave motion when the tube diameter decreases to 6 mu m. (C) 1998 Academic Press. C1 Univ Virginia, Dept Chem Engn, Charlottesville, VA 22903 USA. Univ Tennessee, Dept Chem Engn, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Chem Technol, Oak Ridge, TN 37831 USA. RP Ford, RM (reprint author), Univ Virginia, Dept Chem Engn, Charlottesville, VA 22903 USA. RI Cummings, Peter/B-8762-2013 OI Cummings, Peter/0000-0002-9766-2216 NR 48 TC 24 Z9 27 U1 0 U2 11 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0022-5193 J9 J THEOR BIOL JI J. Theor. Biol. PD DEC 21 PY 1998 VL 195 IS 4 BP 481 EP 504 DI 10.1006/jtbi.1998.0808 PG 24 WC Biology; Mathematical & Computational Biology SC Life Sciences & Biomedicine - Other Topics; Mathematical & Computational Biology GA 147CU UT WOS:000077471000005 PM 9837704 ER PT J AU Ahluwalia, DV AF Ahluwalia, DV TI Nonlocality and gravity-induced CP violation SO MODERN PHYSICS LETTERS A LA English DT Review ID GENERALIZED UNCERTAINTY PRINCIPLE; QUANTUM-GRAVITY; LENGTH; SPACETIME; ANTIGRAVITY; NEUTRINO; EQUATION; PHASES; SYSTEM AB We consider a space-time dependent relative phase between the right- and left-handed spinors and show that it results in a violation of locality in the presence of gravity once the demand of parity covariance is dropped. This violation of locality is such that it readily interprets itself as a gravity-induced CP violation, and at the same time confirms an earlier remark by Wigner that a representation space carries more information than a wave equation. This happens, as Kirchbach has noted, because while the dimensionality of an irreducible representation space does not depend upon the concrete realization of the symmetry generators, Noether currents (Dirac, versus Majorana, versus the CP violating construct presented here) do. The gravity-induced CP violation provides a dynamical reason on how a neutron star carrying its baryon and lepton numbers can collapse into a black hole and loose information on the latter characteristics. C1 Univ Autonoma Zacatecas, Escuela Fis, Zacatecas 98068, Mexico. Los Alamos Natl Lab, Phys Div P25, Los Alamos, NM 87545 USA. RP Univ Autonoma Zacatecas, Escuela Fis, Apartado Postal C-580, Zacatecas 98068, Mexico. EM ahluwalia@phases.reduaz.mx NR 64 TC 9 Z9 9 U1 0 U2 1 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA 5 TOH TUCK LINK, SINGAPORE 596224, SINGAPORE SN 0217-7323 EI 1793-6632 J9 MOD PHYS LETT A JI Mod. Phys. Lett. A PD DEC 21 PY 1998 VL 13 IS 39 BP 3123 EP 3136 DI 10.1142/S0217732398003326 PG 14 WC Physics, Nuclear; Physics, Particles & Fields; Physics, Mathematical SC Physics GA 163KM UT WOS:000078404600001 ER PT J AU Sciolla, G Bajic, A Bard, R Beaulieu, M Blinov, V Borsato, E Boucham, A Boutigny, D Boyarski, A Boyce, R Britton, D Brochu, B Bronzini, F Broomer, B Buccheri, A Caracciolo, R Colecchia, F Coupal, D Cowan, RF Coward, D DalCorso, F Dallapiccola, C DeBonis, I Dorfan, D Dow, S Dusatko, J Erdos, E Fanin, C Fernandez, J Fernholz, R Ferrarotto, F Ferroni, F Fong, D Ford, WT Gaddi, A Galeazzi, F Goodenough, C Gritsan, A Harris, J Harton, J Hasan, A Hearty, C Heise, J Henderson, R Hodgson, J Houde, M Jawahery, H Jeremie, A Johnson, DR Karcher, A Karyotakis, Y Kelsey, M Khan, N Kowalewski, RV Krieg, H Lafaye, R Lamanna, E Lanting, T Levi, M Lu, C MacFarlane, D Malchow, R Martin, JP Mazzoni, MA McDonald, KT McDougald, M McKenna, J Miller, W Momayezi, M Morandin, M Morganti, M Morganti, S Morii, M Nelson, D Palrang, M Park, H Patel, P Piredda, G Pitman, D Posocco, M Raffaelli, F Rankin, P Roney, JM Roy, J Sadrozinski, H Sands, WR Santi, S Schaffner, S Schumm, B Seitz, R Serra, M Smith, JG Smith, AJS Smy, M Snyder, A Spencer, N Stroili, C Taras, P Torassa, E Trischuk, J Voci, C Wagner, S Warner, D Weinstein, A Woch, A Yamamoto, RK Zacek, V vonderLippe, H AF Sciolla, G Bajic, A Bard, R Beaulieu, M Blinov, V Borsato, E Boucham, A Boutigny, D Boyarski, A Boyce, R Britton, D Brochu, B Bronzini, F Broomer, B Buccheri, A Caracciolo, R Colecchia, F Coupal, D Cowan, RF Coward, D DalCorso, F Dallapiccola, C DeBonis, I Dorfan, D Dow, S Dusatko, J Erdos, E Fanin, C Fernandez, J Fernholz, R Ferrarotto, F Ferroni, F Fong, D Ford, WT Gaddi, A Galeazzi, F Goodenough, C Gritsan, A Harris, J Harton, J Hasan, A Hearty, C Heise, J Henderson, R Hodgson, J Houde, M Jawahery, H Jeremie, A Johnson, DR Karcher, A Karyotakis, Y Kelsey, M Khan, N Kowalewski, RV Krieg, H Lafaye, R Lamanna, E Lanting, T Levi, M Lu, C MacFarlane, D Malchow, R Martin, JP Mazzoni, MA McDonald, KT McDougald, M McKenna, J Miller, W Momayezi, M Morandin, M Morganti, M Morganti, S Morii, M Nelson, D Palrang, M Park, H Patel, P Piredda, G Pitman, D Posocco, M Raffaelli, F Rankin, P Roney, JM Roy, J Sadrozinski, H Sands, WR Santi, S Schaffner, S Schumm, B Seitz, R Serra, M Smith, JG Smith, AJS Smy, M Snyder, A Spencer, N Stroili, C Taras, P Torassa, E Trischuk, J Voci, C Wagner, S Warner, D Weinstein, A Woch, A Yamamoto, RK Zacek, V vonderLippe, H TI The BaBar drift chamber SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 8th International Wire Chamber Conference CY FEB 23-27, 1998 CL VIENNA, AUSTRIA AB The central drift chamber for the BaBar detector at the PEP-II B-factory at SLAG is a cylindrical chamber with a length of 280 cm and outer radius of 81 cm. It consists of 40 layers of small hexagonal cells arranged in 10 axial and stereo super layers. In order to minimize multiple scattering, light materials are used for the mechanical structure, and the gas mixture is helium based. The pulse height and timing electronics are mounted directly on the chamber rear end plate. A full-length prototype of the BaBar drift chamber has been built. The analysis of cosmic-ray events measures the spatial resolution averaged in the cell to be 130 mu m and the dE/dx resolution to be 6.8%, meeting the performance goals for the BaBar central tracker. The mechanical assembly and stringing of the chamber was completed in December 1997 and the detector will be integrated into BaBar during summer 1998. (C) 1998 Published by Elsevier Science B.V. All rights reserved. C1 Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. Univ Maryland, Dept Phys, College Pk, MD 20742 USA. Univ Montreal, Grp Phys Particules, Lab Rene JA Levesque, Montreal, PQ H3C 3J7, Canada. Budker Inst Nucl Phys, Novosibirsk 630090, Russia. Ist Nazl Fis Nucl, I-35131 Padua, Italy. Univ Padua, I-35131 Padua, Italy. Lab Annecy Le Vieux Phys Particules, F-74941 Annecy Le Vieux, France. McGill Univ, Montreal, PQ H3A 2T8, Canada. Univ Rome La Sapienza, Ist Nazl Fis Nucl, I-00185 Rome, Italy. Univ Rome La Sapienza, Dipartimento Fis, I-00185 Rome, Italy. Univ Colorado, Dept Phys, Boulder, CO 80309 USA. MIT, Dept Phys, Cambridge, MA 02139 USA. MIT, Nucl Sci Lab, Cambridge, MA 02139 USA. Univ Calif Santa Cruz, Inst Particle Phys, Santa Cruz, CA 95064 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Pisa, Ist Nazl Fis Nucl, I-56010 Pisa, Italy. Univ Pisa, Dipartimento Fis, I-56010 Pisa, Italy. Univ British Columbia, Dept Phys & Astron, Vancouver, BC V6T 1Z1, Canada. Colorado State Univ, Dept Phys, Ft Collins, CO 80523 USA. Univ Victoria, Dept Phys & Astron, Victoria, BC V8W 3P6, Canada. Princeton Univ, Dept Phys, Princeton, NJ 08544 USA. TRIUMF, Vancouver, BC V6T 2A3, Canada. RP Sciolla, G (reprint author), Stanford Linear Accelerator Ctr, POB 4349, Stanford, CA 94309 USA. RI Torassa, Ezio/I-1788-2012; Schaffner, Stephen/D-1189-2011; Lamanna, Ernesto/C-7658-2012; Morandin, Mauro/A-3308-2016; OI Lamanna, Ernesto/0000-0002-7844-8230; Morandin, Mauro/0000-0003-4708-4240; CARACCIOLO, Roberto/0000-0003-0728-1303; Torassa, Ezio/0000-0003-2321-0599 NR 4 TC 5 Z9 6 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD DEC 21 PY 1998 VL 419 IS 2-3 BP 310 EP 314 DI 10.1016/S0168-9002(98)00804-3 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 149WN UT WOS:000077629400016 ER PT J AU Carman, DS Dytman, SA Magahiz, R Mestayer, MD Miskimen, RA Mueller, JA Schumacher, RA Tedeschi, DJ Thompson, RA Wilkin, GR AF Carman, DS Dytman, SA Magahiz, R Mestayer, MD Miskimen, RA Mueller, JA Schumacher, RA Tedeschi, DJ Thompson, RA Wilkin, GR TI The region one drift chamber for the CLAS spectrometer SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 8th International Wire Chamber Conference CY FEB 23-27, 1998 CL VIENNA, AUSTRIA ID SYSTEM AB The Region One detector is the innermost of three nested drift chamber packages of the CLAS spectrometer at Jefferson Laboratory. This detector, with 7776 drift cells, was optimized for the CLAS toroidal magnet geometry, and consists of six wedge-shaped sectors integrated into a single unit. Each sector has thin and relatively weak aluminum endplates which support the large mechanical loads from the wire tensions and associated readout hardware. The unusual feature of the detector is its self-supporting design, wherein the wire tensions of neighboring sectors balance each other without the use of massive structural support. We discuss the design criteria, mechanical components, and assembly procedures. (C) 1998 Published by Elsevier Science B.V. All rights reserved. C1 Carnegie Mellon Univ, Pittsburgh, PA 15213 USA. Univ Pittsburgh, Pittsburgh, PA 15206 USA. Jefferson Lab, Newport News, VA 23606 USA. Univ Massachusetts, Amherst, MA 01003 USA. Univ S Carolina, Columbia, SC 29208 USA. RP Carman, DS (reprint author), Carnegie Mellon Univ, Pittsburgh, PA 15213 USA. RI Schumacher, Reinhard/K-6455-2013 OI Schumacher, Reinhard/0000-0002-3860-1827 NR 6 TC 7 Z9 7 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD DEC 21 PY 1998 VL 419 IS 2-3 BP 315 EP 319 DI 10.1016/S0168-9002(98)00805-5 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 149WN UT WOS:000077629400017 ER PT J AU Acosta, D Blomquist, J Bondar, N Bonushkin, Y Bujak, A Bylsma, B Chrisman, D Durkin, S Eartly, D Ferguson, T Feyzi, F Fisyak, Y Gorn, L Gorn, W Gutay, L Hauser, J Hershman, S Hoftiezer, J Hoorani, H Kiselev, O Korienek, J Korytov, A Layter, J Lennous, P Ling, TY Loveless, R Medved, S Mitselmakher, G Prokofiev, O Razmyslovich, V Rush, C Sedov, S Sobolev, S Soulimov, V Vorobyov, A AF Acosta, D Blomquist, J Bondar, N Bonushkin, Y Bujak, A Bylsma, B Chrisman, D Durkin, S Eartly, D Ferguson, T Feyzi, F Fisyak, Y Gorn, L Gorn, W Gutay, L Hauser, J Hershman, S Hoftiezer, J Hoorani, H Kiselev, O Korienek, J Korytov, A Layter, J Lennous, P Ling, TY Loveless, R Medved, S Mitselmakher, G Prokofiev, O Razmyslovich, V Rush, C Sedov, S Sobolev, S Soulimov, V Vorobyov, A TI Large cathode strip chambers for the CMS endcap muon system SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 8th International Wire Chamber Conference CY FEB 23-27, 1998 CL VIENNA, AUSTRIA AB Presented are the main design features of the large Cathode Strip Chambers (CSCs) for the CMS endcap muon system as well as the performance results obtained with the first large-scale prototype. The 3.4 x 1.2 m(2) six-plane prototype has been reliably operated over one year and the cosmic-ray tests showed that it was capable of detecting muons with similar to 80 mu m spatial and similar to 5 ns time resolutions. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Univ Florida, Gainesville, FL 32611 USA. Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. St Petersburg Nucl Phys Inst, St Petersburg, Russia. Univ Calif Los Angeles, Los Angeles, CA 90024 USA. Purdue Univ, W Lafayette, IN 47907 USA. Ohio State Univ, Athens, OH 45701 USA. Univ Calif Riverside, Riverside, CA 92521 USA. Carnegie Mellon Univ, Pittsburgh, PA 15213 USA. Univ Wisconsin, Madison, WI 53706 USA. Univ Calif Davis, Livermore, CA 95616 USA. RP Korytov, A (reprint author), Univ Florida, Gainesville, FL 32611 USA. RI Ferguson, Thomas/O-3444-2014; Hoorani, Hafeez/D-1791-2013; OI Ferguson, Thomas/0000-0001-5822-3731; Fisyak, Yuri/0000-0002-3151-8377 NR 7 TC 3 Z9 3 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD DEC 21 PY 1998 VL 419 IS 2-3 BP 469 EP 474 DI 10.1016/S0168-9002(98)00822-5 PG 6 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 149WN UT WOS:000077629400043 ER PT J AU Yu, B Smith, GC Siddons, DP Pietraski, PJ AF Yu, B Smith, GC Siddons, DP Pietraski, PJ TI Studies of anode blades for gas proportional detectors SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 8th International Wire Chamber Conference CY FEB 23-27, 1998 CL VIENNA, AUSTRIA DE anode blade ID CHAMBERS AB The use of a thin metal edge, or blade, to generate controlled electron multiplication in a gas has been studied. Measurements with X-rays have been made on assemblies of an anode blade and two adjacent cathodes to determine optimum operating parameters in gas proportional mode, with the goal of producing position sensitive detectors with good position resolution and high counting rate. Under specific conditions, energy resolution comparable to that from a wire proportional chamber can be achieved. The devices are very rugged and can be tailored to a curved geometry for the purposes of eliminating parallax error for small and large angle X-ray scattering experiments. The design of detectors suitable for use with synchrotron radiation, is discussed. (C) 1998 Published by Elsevier Science B.V. All rights reserved. C1 Brookhaven Natl Lab, Instrumentat Div, Upton, NY 11973 USA. RP Yu, B (reprint author), Brookhaven Natl Lab, Instrumentat Div, Bldg 535B, Upton, NY 11973 USA. NR 4 TC 1 Z9 1 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD DEC 21 PY 1998 VL 419 IS 2-3 BP 519 EP 524 DI 10.1016/S0168-9002(98)00828-6 PG 6 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 149WN UT WOS:000077629400052 ER PT J AU Cizeron, R Durand, A Geld, TL Lepeltier, V Meadows, B Ronan, M Sen, S Valassi, A Wormser, G AF Cizeron, R Durand, A Geld, TL Lepeltier, V Meadows, B Ronan, M Sen, S Valassi, A Wormser, G TI A mini-TPC for SLAC B-factory commissioning SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 8th International Wire Chamber Conference CY FEB 23-27, 1998 CL VIENNA, AUSTRIA AB A mini-TPC has been developed for use in PEP-II B-factory beam commissioning and background studies relevant for the BaBar detector. Installed near the intersecting region of the two beams, it has the capability to measure intensities, origins and composition of background particles coming from the e(+)/e(-) beams which produce charged tracks in its volume. (C) 1998 Elsevier Science B.V. All rights reserved. C1 IN2P3, Lab Accelerateur Lineaire, CNRS, F-91898 Orsay, France. Univ Paris Sud, F-91898 Orsay, France. Univ Cincinnati, Cincinnati, OH 45221 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Lepeltier, V (reprint author), IN2P3, Lab Accelerateur Lineaire, CNRS, BP34, F-91898 Orsay, France. RI Valassi, Andrea/K-7506-2012 OI Valassi, Andrea/0000-0001-9322-9565 NR 2 TC 0 Z9 0 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD DEC 21 PY 1998 VL 419 IS 2-3 BP 525 EP 531 DI 10.1016/S0168-9002(98)00829-8 PG 7 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 149WN UT WOS:000077629400053 ER PT J AU Radeka, V Schaknowski, NA Smith, GC Yu, B AF Radeka, V Schaknowski, NA Smith, GC Yu, B TI High-performance, imaging, thermal neutron detectors SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 8th International Wire Chamber Conference CY FEB 23-27, 1998 CL VIENNA, AUSTRIA DE thermal neutron detectors; high flux beam reactors ID POSITION-SENSITIVE DETECTORS AB Existing and planned spallation neutron sources require two-dimensional detectors for many experiments. Unlike the requirements for steady-state neutron sources, it is essential that these detectors possess good time resolution to determine neutron energy. A range of detectors based on gas proportional chambers, with low-noise encoding electronics, has been fabricated at this laboratory, with properties well suited for use at spallation sources. These high-performance detectors possess outstanding qualities in terms of dynamic range and stability of both recorded neutron positions and response (efficiency), in addition to normal attributes such as good position resolution, high detection efficiency and insensitivity to gamma rays. We review here some of the major characteristics of the detectors, describe recent advances, and illustrate their high level of performance with neutron scattering results. While relatively few such detectors are required world wide, specialized efforts are required for their development. The additional opportunities provided by new spallation sources will need continued advances in detector performance. (C) 1998 Published by Elsevier Science B.V. All rights reserved. C1 Brookhaven Natl Lab, Instrumentat Div, Upton, NY 11973 USA. RP Smith, GC (reprint author), Brookhaven Natl Lab, Instrumentat Div, Bldg 535B, Upton, NY 11973 USA. EM gsmith@bnl.gov NR 10 TC 15 Z9 15 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD DEC 21 PY 1998 VL 419 IS 2-3 BP 642 EP 647 DI 10.1016/S0168-9002(98)00844-4 PG 6 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 149WN UT WOS:000077629400072 ER PT J AU Abramov, V Alexeev, G Babintsev, V Baldin, B Butler, J Beutel, D Bezzubov, V Bojko, N Burtovoi, V Chekulaev, S Chi, E Denisov, D Denisov, S Diehl, T Dodonov, V Dyshkant, A Eroshin, O Evdokimov, V Galyaev, A Goncharov, P Gornushkin, Y Green, D Gurzhiev, S Haggerty, H Hanlet, P Hansen, S Hedin, D Ito, A Johns, K Kalinin, A Kostritskiy, A Kozelov, A Kozlovski, E Leitner, R Lokajicek, M Los, S Malyshev, V Mayorov, A Medovikov, V Mokhov, N Nozdrin, A Pisarev, I Pospisil, S Raskowski, J Sabirov, B Simak, V Smith, G Stefanik, A Stoianova, D Suk, M Tokmenin, V Vaniov, V Volkov, A Vorobiev, A Vrba, V Williams, R Wood, D Yatsunenko, Y Yoffe, F Zimin, S AF Abramov, V Alexeev, G Babintsev, V Baldin, B Butler, J Beutel, D Bezzubov, V Bojko, N Burtovoi, V Chekulaev, S Chi, E Denisov, D Denisov, S Diehl, T Dodonov, V Dyshkant, A Eroshin, O Evdokimov, V Galyaev, A Goncharov, P Gornushkin, Y Green, D Gurzhiev, S Haggerty, H Hanlet, P Hansen, S Hedin, D Ito, A Johns, K Kalinin, A Kostritskiy, A Kozelov, A Kozlovski, E Leitner, R Lokajicek, M Los, S Malyshev, V Mayorov, A Medovikov, V Mokhov, N Nozdrin, A Pisarev, I Pospisil, S Raskowski, J Sabirov, B Simak, V Smith, G Stefanik, A Stoianova, D Suk, M Tokmenin, V Vaniov, V Volkov, A Vorobiev, A Vrba, V Williams, R Wood, D Yatsunenko, Y Yoffe, F Zimin, S TI Forward muon system for the D0 detector upgrade SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 8th International Wire Chamber Conference CY FEB 23-27, 1998 CL VIENNA, AUSTRIA DE Tevatron collider; detector upgrade; forward muon system; trigger scintillation counters; mini-drift tubes ID PLASTIC STREAMER TUBES AB The design and main parameters of the completely redesigned DO Forward Angle MUon System (FAMUS: 1.0 < \eta\ < 2.0) for the next high luminosity Tevatron Collider run are reported. Results of the studies of trigger scintillation counters based on fast scintillator Bicron 404A and WLS bars SOFZ-105 are presented. We report about results of test beam studies of prototype counters including minimum ionizing particles detection efficiency, time resolution and amplitude response. Radiation ageing of scintillating materials for the doses up to 1 Mrad, phototubes magnetic shielding in the fields of up to 700 G and ageing of phototubes are presented. Mini-Drift Tubes (MDTs) are chosen as FAMUS tracking detectors. The detector is a drift wire chamber with a metallic cathode. The detector operates in proportional mode with a fast freon-methane gas mixture to provide high drift velocity, adequate counting rate and low ageing. A description of the performance of the MDT is given. Studies of two prototypes in test beams were performed at FNAL and JINR. Obtained coordinate accuracy is around 0.5 mm r.m.s. All tests show robustness of MDT as tracking detector of the new muon system for a long period in high DO background radiation conditions. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Inst High Energy Phys, Neutrino Phys Dept, RU-142284 Protvino, Russia. Joint Inst Nucl Res, Lab Nucl Problems, Dubna, Russia. Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. Boston Univ, Boston, MA 02215 USA. No Illinois Univ, De Kalb, IL 60115 USA. Northeastern Univ, Boston, MA 02115 USA. Univ Arizona, Tucson, AZ 85721 USA. Charles Univ, Fac Math & Phys, Prague, Czech Republic. Acad Sci Czech Republ, Inst Phys, Prague, Czech Republic. Tech Univ, Fac Nucl & Phys Engn, Prague, Czech Republic. RP Gurzhiev, S (reprint author), Inst High Energy Phys, Neutrino Phys Dept, RU-142284 Protvino, Russia. RI Gornushkin, Yury/F-4788-2013; Kozelov, Alexander/J-3812-2014; Chekulaev, Sergey/O-1145-2015 OI Gornushkin, Yury/0000-0003-3524-4032; NR 14 TC 13 Z9 13 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD DEC 21 PY 1998 VL 419 IS 2-3 BP 660 EP 666 DI 10.1016/S0168-9002(98)00866-3 PG 7 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 149WN UT WOS:000077629400075 ER PT J AU Chen, JW Griesshammer, HW Savage, MJ Springer, RP AF Chen, JW Griesshammer, HW Savage, MJ Springer, RP TI gamma-deuteron Compton scattering in effective field theory SO NUCLEAR PHYSICS A LA English DT Article ID NUCLEON-NUCLEON-SCATTERING; CHIRAL PERTURBATION-THEORY; ELECTROMAGNETIC POLARIZABILITIES; ELECTRIC POLARIZABILITY; RANGE INTERACTIONS; LAGRANGIANS; NEUTRON; PROTON; FORCES; RENORMALIZATION AB The differential cross section for gamma-deuteron Compton scattering is computed to next-to-leading order (NLO) in an effective field theory that describes nucleon-nucleon interactions below the pion production threshold. Contributions at NLO include the nucleon isoscalar electric polarizability from its 1/m(pi) behavior in the chiral limit. The parameter-free prediction of the gamma-deuteron differential cross section at NLO is in good agreement with data. (C) 1998 Elsevier Science B.V. C1 Univ Washington, Dept Phys, Seattle, WA 98195 USA. Jefferson Lab, Newport News, VA 23606 USA. Univ Washington, Inst Nucl Theory, Seattle, WA 98195 USA. RP Chen, JW (reprint author), Univ Washington, Dept Phys, Seattle, WA 98195 USA. OI Chen, Jiunn-Wei/0000-0002-8650-9371 NR 62 TC 50 Z9 50 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9474 J9 NUCL PHYS A JI Nucl. Phys. A PD DEC 21 PY 1998 VL 644 IS 3 BP 245 EP 259 DI 10.1016/S0375-9474(98)00591-0 PG 15 WC Physics, Nuclear SC Physics GA 149WD UT WOS:000077628500006 ER PT J AU Khoze, VV Mattis, MP Slater, MJ AF Khoze, VV Mattis, MP Slater, MJ TI The instanton hunter's guide to supersymmetric SU(N) gauge theories SO NUCLEAR PHYSICS B LA English DT Article ID YANG-MILLS THEORY; MULTIINSTANTON CALCULUS; QCD; BREAKING; DUALITY; VACUUM; MODELS; MATTER AB We present a compendium of results for ADHM multi-instantons in SU(N) SUSY gauge theories, followed by applications to N = 2 supersymmetric models. Extending recent SU(2) work, and treating the N = 1 and N = 2 cases in parallel, we construct: (i) the ADHM supermultiplet, (ii) the multi-instanton action, and (iii) the collective coordinate integration measure. Specializing to N = 2, we then give a closed formula for F-k, the k-instanton contribution to the prepotential, as a finite-dimensional collective coordinate integral. This amounts to a weak-coupling solution, in quadratures, of the low-energy dynamics of N = 2 SQCD, without appeal to duality. As an application, we calculate F-1 for all SU(N) and any number of flavors NF; for N-F < 2N - 2 and N-F = 2N - 1 we confirm previous instanton calculations and agree with the proposed hyper-elliptic curve solutions. For N-F = 2N - 2 and N-F = 2N with N > 3 we obtain new results, which in the latter case we do not understand how to reconcile with the curves. (C) 1999 Published by Elsevier Science B.V. C1 Univ Durham, Ctr Particle Theory, Dept Phys, Durham DH1 3LE, England. Los Alamos Natl Lab, Theoret Div T8, Los Alamos, NM 87545 USA. RP Univ Durham, Ctr Particle Theory, Dept Phys, Durham DH1 3LE, England. EM valya.khoze@durham.ac.uk; mattis@pion.lanl.gov; m.j.slater@durham.ac.uk OI Khoze, Valentin V/0000-0003-3006-4147 NR 55 TC 46 Z9 46 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0550-3213 EI 1873-1562 J9 NUCL PHYS B JI Nucl. Phys. B PD DEC 21 PY 1998 VL 536 IS 1-2 BP 69 EP 109 DI 10.1016/S0550-3213(98)00579-3 PG 41 WC Physics, Particles & Fields SC Physics GA 148TB UT WOS:000077547700003 ER PT J AU Abe, F Akimoto, H Akopian, A Albrow, MG Amadon, A Amendolia, SR Amidei, D Antos, J Aota, S Apollinari, G Arisawa, T Asakawa, T Ashmanskas, W Atac, M Azzi-Bacchetta, P Bacchetta, N Bagdasarov, S Bailey, MW de Barbaro, P Barbaro-Galtieri, A Barnes, VE Barnett, BA Barone, M Bauer, G Baumann, T Bedeschi, F Behrends, S Belforte, S Bellettini, G Bellinger, J Benjamin, D Bensinger, J Beretvas, A Berge, JP Berryhill, J Bertolucci, S Bettelli, S Bevensee, B Bhatti, A Biery, K Bigongiari, C Binkley, M Bisello, D Blair, RE Blocker, C Blusk, S Bodek, A Bokhari, W Bolla, G Bonushkin, Y Bortoletto, D Boudreau, J Breccia, L Bromberg, C Bruner, N Brunetti, R Buckley-Geer, E Budd, HS Burkett, K Busetto, G Byon-Wagner, A Byrum, KL Campbell, M Caner, A Carithers, W Carlsmith, D Cassada, J Castro, A Cauz, D Cerri, A Chang, PS Chang, PT Chao, HY Chapman, J Cheng, MT Chertok, M Chiarelli, G Chiou, CN Chlebana, F Christofek, L Chu, ML Cihangir, S Clark, AG Cobal, M Cocca, E Contreras, M Conway, J Cooper, J Cordelli, M Costanzo, D Couyoumtzelis, C Cronin-Hennessy, D Culbertson, R Dagenhart, D Daniels, T DeJongh, F Dell'Agnello, S Dell'Orso, M Demina, R Demortier, L Deninno, M Derwent, PF Devlin, T Dittmann, JR Donati, S Done, J Dorigo, T Eddy, N Einsweiler, K Elias, JE Ely, R Engels, E Erdmann, W Errede, D Errede, S Fan, Q Feild, RG Feng, Z Ferretti, C Fiori, I Flaugher, B Foster, GW Franklin, M Freeman, J Friedman, J Fukui, Y Gadomski, S Galeotti, S Gallinaro, M Ganel, O Garcia-Sciveres, M Garfinkel, AF Gay, C Geer, S Gerdes, DW Giannetti, P Giokaris, N Giromini, P Giusti, G Gold, M Gordon, A Goshaw, AT Gotra, Y Goulianos, K Grassmann, H Groer, L Grosso-Pilcher, C Guillian, G da Costa, JG Guo, RS Haber, C Hafen, E Hahn, SR Hamilton, R Handa, T Handler, R Happacher, F Hara, K Hardman, AD Harris, RM Hartmann, F Hauser, J Hayashi, E Heinrich, J Hao, W Hinrichsen, B Hoffman, KD Hohlmann, M Holck, C Hollebeek, R Holloway, L Huang, Z Huffman, BT Hughes, R Huston, J Huth, J Ikeda, H Incagli, M Incadela, J Introzzi, G Iwai, J Iwata, Y James, E Jensen, H Joshi, U Kajfasz, E Kambara, H Kamon, T Kaneko, T Karr, K Kasha, K Kato, Y Keaffaber, TA Kelley, K Kennedy, RD Kephart, R Kestenbaum, D Khazins, D Kikuchi, T Kim, BJ Kim, HS Kim, SH Kim, YK Kirsch, L Klimenko, S Knoblauch, D Koehn, P Kongeter, A Kondo, K Konigsberg, J Kordas, K Korytov, A Kovacs, E Kowald, W Kroll, J Kruse, M Kuhlmann, SE Kuns, E Kurino, K Kuwabara, T Laasanen, AT Lami, S Lammel, S Lamoureux, JI Lancaster, M Lanzoni, M Latino, G LeCompte, T Leone, S Lewis, JD Limon, P Lindgren, M Liss, TM Liu, JB Liu, YC Lockyer, N Long, O Loomis, C Loreti, M Lucchesi, D Lukens, P Lusin, S Lys, J Maeshima, K Maksimovic, P Mangano, M Mariotti, M Marriner, JP Martignon, G Martin, A Matthews, JAJ Mazzanti, P McFarland, K McIntyre, P Melese, P Menguzzato, M Menzione, A Meschi, E Metzler, S Miao, C Miao, T Michail, G Miller, R Minato, H Miscetti, S Mishina, M Miyashita, S Moggi, N Moore, E Morita, Y Mukherjee, A Muller, T Murat, P Murgia, S Musy, M Nakada, H Nakaya, T Nakano, I Nelson, C Neuberger, D Newman-Holmes, C Ngan, CYP Nodulman, L Nomerotski, A Oh, SH Ohmoto, T Ohsugi, T Oishi, R Okabe, M Okusawa, T Olsen, J Pagliarone, C Paoletti, R Papadimitriou, V Pappas, SP Parashar, N Parri, A Patrick, J Pauletta, G Paulini, M Perazzo, A Pescara, L Peters, MD Phillips, TJ Piacentino, G Pillai, M Pitts, KT Plunkett, R Pompos, A Pondram, L Proudfoot, J Ptohos, F Punzi, G Ragan, K Reher, D Reischl, M Ribon, A Rimondi, F Ristori, L Robertson, WJ Rodrigo, T Rolli, S Rosenson, L Roser, R Saab, T Sakumoto, WK Saltzberg, D Sansoni, A Santi, L Sato, H Schlabach, P Schmidt, EE Schmidt, MP Scott, A Scribano, A Segler, S Seidel, S Seiya, Y Semeria, F Shah, T Shapiro, MD Shaw, NM Shepard, PF Shibayama, T Shimojima, M Shochet, M Siegrist, J Sill, A Sinervo, P Singh, P Sliwa, K Smith, C Snider, FD Spalding, J Speer, T Sphicas, P Spinella, F Spiropulu, M Spiegel, L Stanco, L Steele, J Stefanini, A Strohmer, R Strologas, J Strumia, F Stuart, D Sumorok, K Suzuki, J Suzuki, T Takahashi, T Takano, T Takashima, R Takikawa, K Tanaka, M Tannenbaum, B Tartarelli, F Taylor, W Tecchio, M Teng, PK Teramoto, Y Terashi, K Tether, S Theriot, D Thomas, TL Thurman-Keup, R Timko, M Tipton, P Titov, A Tkaczyk, S Toback, D Tollefson, K Tollestrup, A Toyoda, H Trischuk, W de Troconiz, JF Truitt, S Tseng, J Turini, N Uchida, T Ukegawa, F Valls, J van den Brink, SC Vejcik, S Velev, G Vidal, R Vilar, R Vucinic, D Wagner, RG Wagner, RL Wahl, J Wallace, NB Walsh, AM Wang, C Wang, CH Wang, MJ Warburton, A Watanabe, T Watts, T Webb, R Wei, C Wenzel, H Wester, WC Wicklund, AB Wicklund, E Wilkinson, R Williams, HH Wilson, P Winer, BL Winn, D Wolinski, D Wolinski, J Worm, S Wu, X Wyss, J Yagil, A Yao, W Yasuoka, K Yeh, GP Yeh, P Yoh, J Yosef, C Yoshida, T Yu, I Zanetti, A Zetti, F Zucchelli, S AF Abe, F Akimoto, H Akopian, A Albrow, MG Amadon, A Amendolia, SR Amidei, D Antos, J Aota, S Apollinari, G Arisawa, T Asakawa, T Ashmanskas, W Atac, M Azzi-Bacchetta, P Bacchetta, N Bagdasarov, S Bailey, MW de Barbaro, P Barbaro-Galtieri, A Barnes, VE Barnett, BA Barone, M Bauer, G Baumann, T Bedeschi, F Behrends, S Belforte, S Bellettini, G Bellinger, J Benjamin, D Bensinger, J Beretvas, A Berge, JP Berryhill, J Bertolucci, S Bettelli, S Bevensee, B Bhatti, A Biery, K Bigongiari, C Binkley, M Bisello, D Blair, RE Blocker, C Blusk, S Bodek, A Bokhari, W Bolla, G Bonushkin, Y Bortoletto, D Boudreau, J Breccia, L Bromberg, C Bruner, N Brunetti, R Buckley-Geer, E Budd, HS Burkett, K Busetto, G Byon-Wagner, A Byrum, KL Campbell, M Caner, A Carithers, W Carlsmith, D Cassada, J Castro, A Cauz, D Cerri, A Chang, PS Chang, PT Chao, HY Chapman, J Cheng, MT Chertok, M Chiarelli, G Chiou, CN Chlebana, F Christofek, L Chu, ML Cihangir, S Clark, AG Cobal, M Cocca, E Contreras, M Conway, J Cooper, J Cordelli, M Costanzo, D Couyoumtzelis, C Cronin-Hennessy, D Culbertson, R Dagenhart, D Daniels, T DeJongh, F Dell'Agnello, S Dell'Orso, M Demina, R Demortier, L Deninno, M Derwent, PF Devlin, T Dittmann, JR Donati, S Done, J Dorigo, T Eddy, N Einsweiler, K Elias, JE Ely, R Engels, E Erdmann, W Errede, D Errede, S Fan, Q Feild, RG Feng, Z Ferretti, C Fiori, I Flaugher, B Foster, GW Franklin, M Freeman, J Friedman, J Fukui, Y Gadomski, S Galeotti, S Gallinaro, M Ganel, O Garcia-Sciveres, M Garfinkel, AF Gay, C Geer, S Gerdes, DW Giannetti, P Giokaris, N Giromini, P Giusti, G Gold, M Gordon, A Goshaw, AT Gotra, Y Goulianos, K Grassmann, H Groer, L Grosso-Pilcher, C Guillian, G da Costa, JG Guo, RS Haber, C Hafen, E Hahn, SR Hamilton, R Handa, T Handler, R Happacher, F Hara, K Hardman, AD Harris, RM Hartmann, F Hauser, J Hayashi, E Heinrich, J Hao, W Hinrichsen, B Hoffman, KD Hohlmann, M Holck, C Hollebeek, R Holloway, L Huang, Z Huffman, BT Hughes, R Huston, J Huth, J Ikeda, H Incagli, M Incadela, J Introzzi, G Iwai, J Iwata, Y James, E Jensen, H Joshi, U Kajfasz, E Kambara, H Kamon, T Kaneko, T Karr, K Kasha, K Kato, Y Keaffaber, TA Kelley, K Kennedy, RD Kephart, R Kestenbaum, D Khazins, D Kikuchi, T Kim, BJ Kim, HS Kim, SH Kim, YK Kirsch, L Klimenko, S Knoblauch, D Koehn, P Kongeter, A Kondo, K Konigsberg, J Kordas, K Korytov, A Kovacs, E Kowald, W Kroll, J Kruse, M Kuhlmann, SE Kuns, E Kurino, K Kuwabara, T Laasanen, AT Lami, S Lammel, S Lamoureux, JI Lancaster, M Lanzoni, M Latino, G LeCompte, T Leone, S Lewis, JD Limon, P Lindgren, M Liss, TM Liu, JB Liu, YC Lockyer, N Long, O Loomis, C Loreti, M Lucchesi, D Lukens, P Lusin, S Lys, J Maeshima, K Maksimovic, P Mangano, M Mariotti, M Marriner, JP Martignon, G Martin, A Matthews, JAJ Mazzanti, P McFarland, K McIntyre, P Melese, P Menguzzato, M Menzione, A Meschi, E Metzler, S Miao, C Miao, T Michail, G Miller, R Minato, H Miscetti, S Mishina, M Miyashita, S Moggi, N Moore, E Morita, Y Mukherjee, A Muller, T Murat, P Murgia, S Musy, M Nakada, H Nakaya, T Nakano, I Nelson, C Neuberger, D Newman-Holmes, C Ngan, CYP Nodulman, L Nomerotski, A Oh, SH Ohmoto, T Ohsugi, T Oishi, R Okabe, M Okusawa, T Olsen, J Pagliarone, C Paoletti, R Papadimitriou, V Pappas, SP Parashar, N Parri, A Patrick, J Pauletta, G Paulini, M Perazzo, A Pescara, L Peters, MD Phillips, TJ Piacentino, G Pillai, M Pitts, KT Plunkett, R Pompos, A Pondram, L Proudfoot, J Ptohos, F Punzi, G Ragan, K Reher, D Reischl, M Ribon, A Rimondi, F Ristori, L Robertson, WJ Rodrigo, T Rolli, S Rosenson, L Roser, R Saab, T Sakumoto, WK Saltzberg, D Sansoni, A Santi, L Sato, H Schlabach, P Schmidt, EE Schmidt, MP Scott, A Scribano, A Segler, S Seidel, S Seiya, Y Semeria, F Shah, T Shapiro, MD Shaw, NM Shepard, PF Shibayama, T Shimojima, M Shochet, M Siegrist, J Sill, A Sinervo, P Singh, P Sliwa, K Smith, C Snider, FD Spalding, J Speer, T Sphicas, P Spinella, F Spiropulu, M Spiegel, L Stanco, L Steele, J Stefanini, A Strohmer, R Strologas, J Strumia, F Stuart, D Sumorok, K Suzuki, J Suzuki, T Takahashi, T Takano, T Takashima, R Takikawa, K Tanaka, M Tannenbaum, B Tartarelli, F Taylor, W Tecchio, M Teng, PK Teramoto, Y Terashi, K Tether, S Theriot, D Thomas, TL Thurman-Keup, R Timko, M Tipton, P Titov, A Tkaczyk, S Toback, D Tollefson, K Tollestrup, A Toyoda, H Trischuk, W de Troconiz, JF Truitt, S Tseng, J Turini, N Uchida, T Ukegawa, F Valls, J van den Brink, SC Vejcik, S Velev, G Vidal, R Vilar, R Vucinic, D Wagner, RG Wagner, RL Wahl, J Wallace, NB Walsh, AM Wang, C Wang, CH Wang, MJ Warburton, A Watanabe, T Watts, T Webb, R Wei, C Wenzel, H Wester, WC Wicklund, AB Wicklund, E Wilkinson, R Williams, HH Wilson, P Winer, BL Winn, D Wolinski, D Wolinski, J Worm, S Wu, X Wyss, J Yagil, A Yao, W Yasuoka, K Yeh, GP Yeh, P Yoh, J Yosef, C Yoshida, T Yu, I Zanetti, A Zetti, F Zucchelli, S TI Measurement of the CP-violation parameter sin(2 beta) in B-d(0)/(B)over-bar(d)(0)-> J/psi K-S(0) decays SO PHYSICAL REVIEW LETTERS LA English DT Article ID DETECTOR AB We present a measurement of the time-dependent asymmetry in the rate for (B)over-bar(d)(0) versus B-d(0) decays to J/psi K-S(0). A nonzero asymmetry would be an indication of CP violation, and within the standard model this may be used to measure the CP-violation parameter sin(2 beta). A total of 198 +/- 17 B-d(0)/(B)over-bar(d)(0) decays were observed in p(p)over-bar collisions at root s = 1.8 TeV by the CDF detector at the Fermilab Tevatron. B-d(0) and (B)over-bar(d)(0) are distinguished by a technique based on charge correlations from hadronization of the b quark. Our analysis results in sin(2 beta) = 1.8 +/- 1.1 (stat) +/- 0.3(syst). C1 Argonne Natl Lab, Argonne, IL 60439 USA. Univ Bologna, Ist Nazl Fis Nucl, I-40127 Bologna, Italy. Brandeis Univ, Waltham, MA 02254 USA. Univ Calif Los Angeles, Los Angeles, CA 90024 USA. Univ Chicago, Chicago, IL 60637 USA. Duke Univ, Durham, NC 27708 USA. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Florida, Gainesville, FL 32611 USA. Ist Nazl Fis Nucl, Lab Nazl Frascati, I-00044 Frascati, Italy. Univ Geneva, CH-1211 Geneva 4, Switzerland. Harvard Univ, Cambridge, MA 02138 USA. Hiroshima Univ, Higashihiroshima 724, Japan. Univ Illinois, Urbana, IL 61801 USA. McGill Univ, Inst Particle Phys, Montreal, PQ H3A 2T8, Canada. Univ Toronto, Toronto, ON M5S 1A7, Canada. Johns Hopkins Univ, Baltimore, MD 21218 USA. Univ Karlsruhe, Inst Expt Kernphys, D-76128 Karlsruhe, Germany. Natl Lab High Energy Phys, KEK, Tsukuba, Ibaraki 305, Japan. Ernest Orlando Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. MIT, Cambridge, MA 02139 USA. Univ Michigan, Ann Arbor, MI 48109 USA. Michigan State Univ, E Lansing, MI 48824 USA. Univ New Mexico, Albuquerque, NM 87131 USA. Ohio State Univ, Columbus, OH 43210 USA. Osaka City Univ, Osaka 588, Japan. Univ Padua, Ist Nazl Fis Nucl, Sez Padova, I-35131 Padua, Italy. Univ Penn, Philadelphia, PA 19104 USA. Univ Pisa, Ist Nazl Fis Nucl, I-56100 Pisa, Italy. Scuola Normale Super Pisa, I-56100 Pisa, Italy. Univ Pittsburgh, Pittsburgh, PA 15260 USA. Purdue Univ, W Lafayette, IN 47907 USA. Univ Rochester, Rochester, NY 14627 USA. Rockefeller Univ, New York, NY 10021 USA. Rutgers State Univ, Piscataway, NJ 08855 USA. Acad Sinica, Taipei 11530, Taiwan. Texas A&M Univ, College Stn, TX 77843 USA. Texas Tech Univ, Lubbock, TX 79409 USA. Univ Trieste, Ist Nazl Fis Nucl, Udine, Italy. Univ Tsukuba, Tokyo, Ibaraki 315, Japan. Tufts Univ, Medford, MA 02155 USA. Waseda Univ, Tokyo 169, Japan. Univ Wisconsin, Madison, WI 53706 USA. Yale Univ, New Haven, CT 06520 USA. RP Abe, F (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Lancaster, Mark/C-1693-2008; Vucinic, Dejan/C-2406-2008; Nomerotski, Andrei/A-5169-2010; Azzi, Patrizia/H-5404-2012; Punzi, Giovanni/J-4947-2012; Chiarelli, Giorgio/E-8953-2012; Warburton, Andreas/N-8028-2013; Paulini, Manfred/N-7794-2014; Introzzi, Gianluca/K-2497-2015 OI Azzi, Patrizia/0000-0002-3129-828X; Punzi, Giovanni/0000-0002-8346-9052; Chiarelli, Giorgio/0000-0001-9851-4816; Warburton, Andreas/0000-0002-2298-7315; Paulini, Manfred/0000-0002-6714-5787; Introzzi, Gianluca/0000-0002-1314-2580 NR 23 TC 50 Z9 50 U1 0 U2 3 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD DEC 21 PY 1998 VL 81 IS 25 BP 5513 EP 5518 DI 10.1103/PhysRevLett.81.5513 PG 6 WC Physics, Multidisciplinary SC Physics GA 150HT UT WOS:000077659500010 ER PT J AU Ackerstaff, K Airapetian, A Akopov, N Akushevich, I Amarian, M Ashenauer, EC Avakian, H Avakian, R Avetissian, A Bains, B Baumgarten, C Beckmann, M Belostotski, S Belz, JE Benisch, T Bernreuther, S Bianchi, N Blouw, J Bottcher, H Borissov, A Brack, J Brauksiepe, S Braun, B Bray, B Brons, S Bruckner, W Brull, A Bruins, EEW Bulten, KJ Cadman, RV Capitani, GP Carter, P Chumney, P Cisbani, E Court, GR Dalpiaz, PF De Sanctis, E De Schepper, D Devitsin, E Huberts, PKAD Di Nezza, P Duren, M Dvoredsky, A Elbakian, G Fantoni, A Fechtchenko, A Ferstl, M Fiedler, K Filippone, BW Fischer, H Fox, B Franz, J Frullani, S Funk, MA Gagunashvili, ND Gao, H Garber, Y Garibaldi, F Gavrilov, G Geiger, P Gharibyan, V Giordjian, V Golendukhin, A Graw, G Grebeniouk, O Green, PW Greeniaus, LG Grosshauser, C Gute, A Haeberli, W Hansen, JO Hasch, D Hausser, O Henderson, R Henkes, T Henoch, M Hertenberger, R Holler, Y Holt, RJ Hoprich, W Ihssen, H Iodice, M Izotov, A Jackson, HE Jgoun, A Kaiser, R Kinney, E Kisselev, A Kitching, P Kobayashi, H Koch, N Konigsmann, K Kolstein, M Kolster, H Korotkov, V Korsch, W Kozlov, V Kramer, LH Krivokhijine, VG Kurisuno, M Kyle, G Lachnit, W Lorenzon, W Makins, NCR Manaenkov, SI Martens, FK Martin, JW Masoli, F Mateos, A McAndrew, M McIlhany, K McKeown, RD Menden, FM Meissner, F Metz, A Meyners, N Mikloukho, O Miller, CA Miller, MA Milner, R Mitsyn, V Most, A Mozzetti, R Muccifora, V Nagaitsev, A Naryshkin, Y Nathan, AM Neunreither, F Niczyporuk, M Nowak, WD Nupieri, M O'Neill, TG Ouyang, J Owen, BR Papavassiliou, V Pate, SF Pitt, M Potashov, S Potterveld, DH Rakness, G Reali, A Redwine, R Reolon, AR Ristinen, R Rith, K Roloff, H Rossi, P Rudnitsky, S Ruh, M Ryckbosch, D Sakemi, Y Savin, I Schmidt, F Schmitt, H Schnell, G Schuler, KP Schwind, A Shibata, TA Shibatani, K Shin, T Shutov, V Simani, C Simon, A Sinram, K Slavich, P Spengos, M Steffens, E Stenger, J Stewart, J Stoesslein, U Sutter, M Tallini, H Taroian, S Terkulov, A Tipton, B Tytgat, M Urciuoli, GM van Hunen, JJ de Vyver, RV van den Brand, JFJ van der Steenhoven, G Vetterli, MC Vincter, MG Volk, E Wander, W Williamson, SE Wise, T Woller, K Yoneyama, S Zohrabian, H AF Ackerstaff, K Airapetian, A Akopov, N Akushevich, I Amarian, M Ashenauer, EC Avakian, H Avakian, R Avetissian, A Bains, B Baumgarten, C Beckmann, M Belostotski, S Belz, JE Benisch, T Bernreuther, S Bianchi, N Blouw, J Bottcher, H Borissov, A Brack, J Brauksiepe, S Braun, B Bray, B Brons, S Bruckner, W Brull, A Bruins, EEW Bulten, KJ Cadman, RV Capitani, GP Carter, P Chumney, P Cisbani, E Court, GR Dalpiaz, PF De Sanctis, E De Schepper, D Devitsin, E Huberts, PKAD Di Nezza, P Duren, M Dvoredsky, A Elbakian, G Fantoni, A Fechtchenko, A Ferstl, M Fiedler, K Filippone, BW Fischer, H Fox, B Franz, J Frullani, S Funk, MA Gagunashvili, ND Gao, H Garber, Y Garibaldi, F Gavrilov, G Geiger, P Gharibyan, V Giordjian, V Golendukhin, A Graw, G Grebeniouk, O Green, PW Greeniaus, LG Grosshauser, C Gute, A Haeberli, W Hansen, JO Hasch, D Hausser, O Henderson, R Henkes, T Henoch, M Hertenberger, R Holler, Y Holt, RJ Hoprich, W Ihssen, H Iodice, M Izotov, A Jackson, HE Jgoun, A Kaiser, R Kinney, E Kisselev, A Kitching, P Kobayashi, H Koch, N Konigsmann, K Kolstein, M Kolster, H Korotkov, V Korsch, W Kozlov, V Kramer, LH Krivokhijine, VG Kurisuno, M Kyle, G Lachnit, W Lorenzon, W Makins, NCR Manaenkov, SI Martens, FK Martin, JW Masoli, F Mateos, A McAndrew, M McIlhany, K McKeown, RD Menden, FM Meissner, F Metz, A Meyners, N Mikloukho, O Miller, CA Miller, MA Milner, R Mitsyn, V Most, A Mozzetti, R Muccifora, V Nagaitsev, A Naryshkin, Y Nathan, AM Neunreither, F Niczyporuk, M Nowak, WD Nupieri, M O'Neill, TG Ouyang, J Owen, BR Papavassiliou, V Pate, SF Pitt, M Potashov, S Potterveld, DH Rakness, G Reali, A Redwine, R Reolon, AR Ristinen, R Rith, K Roloff, H Rossi, P Rudnitsky, S Ruh, M Ryckbosch, D Sakemi, Y Savin, I Schmidt, F Schmitt, H Schnell, G Schuler, KP Schwind, A Shibata, TA Shibatani, K Shin, T Shutov, V Simani, C Simon, A Sinram, K Slavich, P Spengos, M Steffens, E Stenger, J Stewart, J Stoesslein, U Sutter, M Tallini, H Taroian, S Terkulov, A Tipton, B Tytgat, M Urciuoli, GM van Hunen, JJ de Vyver, RV van den Brand, JFJ van der Steenhoven, G Vetterli, MC Vincter, MG Volk, E Wander, W Williamson, SE Wise, T Woller, K Yoneyama, S Zohrabian, H TI Flavor asymmetry of the light quark sea from semi-inclusive deep-inelastic scattering SO PHYSICAL REVIEW LETTERS LA English DT Article ID DRELL-YAN PROCESS; PARTON DISTRIBUTIONS; BREAKING; NUCLEON; PROTON AB The flavor asymmetry of the light quark sea of the nucleon is determined in the kinematic range 0.02 < x < 0.3 and 1 < Q(2) < 10 GeV2 for the first time from semi-inclusive deep-inelastic scattering. The quantity [(d) over bar(x) - (u) over bar(x)]/[u(x) - d(x)] is derived from a relationship between the yields of positive and negative pions from unpolarized hydrogen and deuterium targets. The flavor asymmetry (d) over bar - (u) over bar is found to be nonzero and x dependent, showing an excess of (d) over bar over (u) over bar quarks in the proton. C1 Univ Alberta, Dept Phys, Edmonton, AB T6G 2J1, Canada. Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. CALTECH, WK Kellogg Radiat Lab, Pasadena, CA 91125 USA. Univ Colorado, Nucl Phys Lab, Boulder, CO 80309 USA. DESY, D-22603 Hamburg, Germany. DESY, D-15738 Zeuthen, Germany. Joint Inst Nucl Res, Dubna 141980, Russia. Univ Erlangen Nurnberg, Inst Phys, D-91058 Erlangen, Germany. Univ Ferrara, Dipartmento Fis, I-44100 Ferrara, Italy. Ist Nazl Fis Nucl, Lab Nazl Frascati, I-00044 Frascati, Italy. Florida Int Univ, Dept Phys, Miami, FL 33199 USA. Univ Freiburg, Fak Phys, D-79104 Freiburg, Germany. State Univ Ghent, Dept Subatom & Radiat Phys, B-9000 Ghent, Belgium. Max Planck Inst Kernphys, D-69029 Heidelberg, Germany. Univ Illinois, Dept Phys, Urbana, IL 61801 USA. Univ Kentucky, Dept Phys & Astron, Lexington, KY 40506 USA. Univ Liverpool, Dept Phys, Liverpool L69 7ZE, Merseyside, England. Univ Wisconsin, Dept Phys, Madison, WI 53706 USA. Univ Marburg, Inst Phys, D-35037 Marburg, Germany. MIT, Nucl Sci Lab, Cambridge, MA 02139 USA. Univ Michigan, Randall Lab Phys, Ann Arbor, MI 48109 USA. PN Lebedev Phys Inst, Moscow 117924, Russia. Univ Munich, Sekt Phys, D-85748 Garching, Germany. New Mexico State Univ, Dept Phys, Las Cruces, NM 88003 USA. NIKHEF H, NL-1009 DB Amsterdam, Netherlands. Petersburg Nucl Phys Inst, St Petersburg 188350, Russia. Ist Nazl Fis Nucl, Sez Sanita, I-00161 Rome, Italy. Ist Super Sanita, Phys Lab, I-00161 Rome, Italy. Simon Fraser Univ, Dept Phys, Burnaby, BC V5A 1S6, Canada. TRIUMF, Vancouver, BC V6T 2A3, Canada. Tokyo Inst Technol, Tokyo 152, Japan. Vrije Univ Amsterdam, Dept Phys & Astron, NL-1081 HV Amsterdam, Netherlands. Yerevan Phys Inst, Yerevan 375036, Armenia. RP Ackerstaff, K (reprint author), Univ Alberta, Dept Phys, Edmonton, AB T6G 2J1, Canada. RI Gao, Haiyan/G-2589-2011; Gavrilov, Gennady/C-6260-2013; Holt, Roy/E-5803-2011; Kozlov, Valentin/M-8000-2015; Terkulov, Adel/M-8581-2015; Cisbani, Evaristo/C-9249-2011 OI Cisbani, Evaristo/0000-0002-6774-8473 NR 19 TC 174 Z9 175 U1 1 U2 3 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD DEC 21 PY 1998 VL 81 IS 25 BP 5519 EP 5523 DI 10.1103/PhysRevLett.81.5519 PG 5 WC Physics, Multidisciplinary SC Physics GA 150HT UT WOS:000077659500011 ER PT J AU Fasoli, A Breizman, BN Borba, D Heeter, RF Pekker, MS Sharapov, SE AF Fasoli, A Breizman, BN Borba, D Heeter, RF Pekker, MS Sharapov, SE TI Nonlinear splitting of fast particle driven waves in a plasma: Observation and theory SO PHYSICAL REVIEW LETTERS LA English DT Article ID INDUCED ALFVEN EIGENMODES; INSTABILITIES; EXCITATION; TOKAMAK AB The measured spectra of fast particle driven Alfven eigenmodes in the JET tokamak plasma are interpreted on the basis of a nonlinear model of near-threshold kinetic instabilities. The observed mode splitting is a manifestation of the general nonlinear phenomena due to the combination of resonant wave-particle interaction and collisionlike relaxation of the resonant particles. The instability growth rate and the effective collision frequency of the resonant particles are determined. C1 Jet Joint Undertaking, Abingdon OX14 3EA, Oxon, England. MIT, Plasma Sci & Fus Ctr, Cambridge, MA 02139 USA. Univ Texas, Inst Fus Studies, Austin, TX 78712 USA. Inst Super Tecn, EURATOM, P-1096 Lisbon, Portugal. Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Fasoli, A (reprint author), Jet Joint Undertaking, Abingdon OX14 3EA, Oxon, England. RI Borba, Duarte/K-6148-2015 OI Borba, Duarte/0000-0001-5305-2857 NR 13 TC 65 Z9 65 U1 1 U2 10 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD DEC 21 PY 1998 VL 81 IS 25 BP 5564 EP 5567 DI 10.1103/PhysRevLett.81.5564 PG 4 WC Physics, Multidisciplinary SC Physics GA 150HT UT WOS:000077659500022 ER PT J AU Godbert-Mouret, L Meftah, T Calisti, A Stamm, R Talin, B Gigosos, M Cardenoso, V Alexiou, S Lee, RW Klein, L AF Godbert-Mouret, L Meftah, T Calisti, A Stamm, R Talin, B Gigosos, M Cardenoso, V Alexiou, S Lee, RW Klein, L TI Accuracy of stark broadening calculations for ionic emitters SO PHYSICAL REVIEW LETTERS LA English DT Article ID II-P-ALPHA; STRONGLY COUPLED PLASMAS; DENSE-PLASMAS; C-IV; PROFILE CALCULATIONS; COLLISION OPERATOR; LINE-SHAPES; N-V; HYDROGEN; DYNAMICS AB The standard static-ion impact electron theory of line broadening is assessed with a calculation of the He II P-alpha line over a broad range of plasma conditions. Ion dynamics, an improved electron collision operator, and accurate atomic physics are included in the computation. Simulations also have been performed to validate effects included in the calculation at higher densities. Calculated linewidths are compared with experiment over more than two decades in electron density, and broad agreement is found. This provides the first critical evaluation of the assumptions of Stark broadening theory. The profiles also display the first unambiguous evidence of ion dynamics. C1 Univ Aix Marseille 1, Ctr St Jerome, UMR 6633, PIIM, F-13397 Marseille 20, France. Univ Valladolid, E-47071 Valladolid, Spain. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Howard Univ, Dept Phys, Washington, DC 20059 USA. RP Godbert-Mouret, L (reprint author), Univ Aix Marseille 1, Ctr St Jerome, UMR 6633, PIIM, F-13397 Marseille 20, France. RI Cardenoso-Payo, Valentin/L-8755-2014; Gigosos, Marco/D-5530-2016; OI Cardenoso-Payo, Valentin/0000-0003-1460-158X; Gigosos, Marco/0000-0002-1057-9250; Calisti, Annette/0000-0001-6727-9286 NR 28 TC 16 Z9 15 U1 1 U2 7 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD DEC 21 PY 1998 VL 81 IS 25 BP 5568 EP 5571 DI 10.1103/PhysRevLett.81.5568 PG 4 WC Physics, Multidisciplinary SC Physics GA 150HT UT WOS:000077659500023 ER PT J AU de Andrade, MC Chau, R Dickey, RP Dilley, NR Freeman, EJ Gajewski, DA Maple, MB AF de Andrade, MC Chau, R Dickey, RP Dilley, NR Freeman, EJ Gajewski, DA Maple, MB TI Evidence for a common physical description of non-Fermi-liquid behavior in chemically substituted f-electron systems SO PHYSICAL REVIEW LETTERS LA English DT Article ID KONDO DISORDER; UCU5-XPDX; ALLOYS AB The non-Fermi-liquid (NFL) behavior observed in the low temperature specific heat C(T) and magnetic susceptibility chi(T) of many chemically substituted f-electron systems is analyzed within the context of a recently developed theory based on Griffiths' singularities. Measurements of C(T) and chi(T) in the systems Th1-xUxPd2Al3, Y1-xUxPd3, and UCu5-xMx (M = Pd, Pt) are found to be consistent with C(T)/T proportional to chi(T) proportional to T-1+lambda predicted by this model with lambda < 1 in the NFL regime. These results suggest that the NFL properties observed in a wide variety of disordered f-electron systems can be described within the context of a common physical picture. C1 Univ Calif San Diego, Dept Phys, La Jolla, CA 92093 USA. Univ Calif San Diego, Inst Pure & Appl Phys Sci, La Jolla, CA 92093 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Calif Riverside, Dept Phys, Riverside, CA 92521 USA. IBM Corp, Almaden Res Ctr, San Jose, CA 95120 USA. RP de Andrade, MC (reprint author), Univ Calif San Diego, Dept Phys, La Jolla, CA 92093 USA. NR 22 TC 108 Z9 108 U1 1 U2 4 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 EI 1079-7114 J9 PHYS REV LETT JI Phys. Rev. Lett. PD DEC 21 PY 1998 VL 81 IS 25 BP 5620 EP 5623 DI 10.1103/PhysRevLett.81.5620 PG 4 WC Physics, Multidisciplinary SC Physics GA 150HT UT WOS:000077659500036 ER PT J AU Knill, E Laflamme, R AF Knill, E Laflamme, R TI Power of one bit of quantum information SO PHYSICAL REVIEW LETTERS LA English DT Article ID COMPUTATION; UNIVERSAL; GATES AB In standard quantum computation, the initial state is pure and the answer is determined by making a measurement of some of the bits in the computational basis. What can be accomplished if the initial state is a highly mixed state and the answer is determined by measuring the expectation of a, on the first bit with bounded sensitivity? This is the situation in high temperature ensemble quantum computation. We show that in this model it is possible to perform interesting physics simulations that have no known efficient classical algorithms, even though the model is less powerful than standard quantum computation in the presence of oracles. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87455 USA. RP Knill, E (reprint author), Univ Calif Los Alamos Natl Lab, MS B265, Los Alamos, NM 87455 USA. NR 18 TC 446 Z9 457 U1 3 U2 11 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD DEC 21 PY 1998 VL 81 IS 25 BP 5672 EP 5675 DI 10.1103/PhysRevLett.81.5672 PG 4 WC Physics, Multidisciplinary SC Physics GA 150HT UT WOS:000077659500049 ER PT J AU Castillo, VM Hoover, WG AF Castillo, VM Hoover, WG TI Comment on "Maximum of the local entropy production becomes minimal in stationary processes" SO PHYSICAL REVIEW LETTERS LA English DT Article C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Univ Calif Davis, Livermore, CA 94551 USA. RP Castillo, VM (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 6 TC 3 Z9 3 U1 2 U2 3 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD DEC 21 PY 1998 VL 81 IS 25 BP 5700 EP 5700 DI 10.1103/PhysRevLett.81.5700 PG 1 WC Physics, Multidisciplinary SC Physics GA 150HT UT WOS:000077659500056 ER PT J AU Wunderlich, B Okazaki, I Ishikiriyama, K Boller, A AF Wunderlich, B Okazaki, I Ishikiriyama, K Boller, A TI Melting by temperature-modulated calorimetry SO THERMOCHIMICA ACTA LA English DT Article; Proceedings Paper CT 25th North American Thermal Analysis Conference CY SEP 07-09, 1997 CL MCLEAN, VIRGINIA DE crystallization; crystal nucleation; irreversible melting; locally reversible melting; melting; molecular nucleation; temperature-modulated calorimetry ID DIFFERENTIAL SCANNING CALORIMETRY; HEAT-CAPACITY; DSC AB Well-crystallized macromolecules melt irreversibly due to the need of molecular nucleation, while small molecules melt reversibly as long as crystal nuclei are present to assist crystallization. Furthermore, imperfect crystals of low-molar-mass polymers may have a sufficiently small region of metastability between crystallization and melting to show a reversing heatflow component due to melting of poor crystals followed by crystallization of imperfect crystals which have insufficient time to perfect before the modulation switches to heating and melts the imperfect crystals. Many metals, in turn, melt sharply and reversibly as long as nuclei remain after melting for subsequent crystallization during the cooling cycle. Their analysis is complicated, however, due to thermal conductivity limitations of the calorimeters. Polymers of sufficiently high molar mass, finally, show a small amount of reversible, local melting that may be linked to partial melting of individual molecules. Experiments by temperature-modulated calorimetry and model calculations are presented. The samples measured included poly(ethylene terephthalate), poly(ethylene oxide)s, and indium. Two unsolved problems that arose from this research involve the origin of a high, seemingly stable, reversible heat capacity of polymers in the melting region, and a smoothing of melting and crystallization into a close-to-elliptical Lissajous figure in a heat-flow versus sample-temperature plot. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Wunderlich, B (reprint author), Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. NR 15 TC 38 Z9 40 U1 0 U2 11 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0040-6031 J9 THERMOCHIM ACTA JI Thermochim. Acta PD DEC 21 PY 1998 VL 324 IS 1-2 BP 77 EP 85 DI 10.1016/S0040-6031(98)00525-5 PG 9 WC Thermodynamics; Chemistry, Analytical; Chemistry, Physical SC Thermodynamics; Chemistry GA 152FX UT WOS:000077766600010 ER PT J AU Chen, W Dadmun, M Zhang, G Boller, A Wunderlich, B AF Chen, W Dadmun, M Zhang, G Boller, A Wunderlich, B TI Isotropization of nematic liquid crystals by TMDSC SO THERMOCHIMICA ACTA LA English DT Article; Proceedings Paper CT 25th North American Thermal Analysis Conference CY SEP 07-09, 1997 CL MCLEAN, VIRGINIA DE liquid crystal; macromolecule; nematic liquid crystal; quasi-isothermal measurement; reversible transition; small molecule; temperature-modulated calorimetry; transition ID DIFFERENTIAL SCANNING CALORIMETRY; HEAT-CAPACITY; TEMPERATURE; DSC AB Temperature-modulated differential scanning calorimetry (TMDSC) and traditional DSC are used to study the transition between the nematic liquid crystalline state and the isotropic liquid for two small molecules [4,4'-azoxyanisole and N,N'-bis(4-n-octyloxybenzal)-1,4-phenylenediamine] and one macromolecule (4,4'-dihydroxy-alpha-methylstilbene copolymerized with a 1 : 1 molar mixture of 1,7-dibromoheptane and 1,9-dibromononane). The DSC measurements with 4,4'-azoxyanisole were used for temperature calibration with varying heating and cooling rates. The breadths of the transitions were analyzed with quasi-isothermal TMDSC, using a small temperature-modulation amplitude and standard TMDSC with underlying heating and cooling rates. It could be verified that the isotropization transition of a nematic liquid crystal is, indeed, reversible for all three molecules. The nature of the transition changes, however, from relatively sharp for small and rigid molecules, to about 3 K wide for the small molecule with flexible ends, and to as broad as 20 K for the macromolecule. It was also demonstrated that quantitative heats of fusion of sharp transitions can be extracted from TMDSC, but only from the heat-flow signal in the time domain. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Chen, W (reprint author), Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. OI Dadmun, Mark/0000-0003-4304-6087 NR 17 TC 16 Z9 16 U1 1 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0040-6031 J9 THERMOCHIM ACTA JI Thermochim. Acta PD DEC 21 PY 1998 VL 324 IS 1-2 BP 87 EP 94 DI 10.1016/S0040-6031(98)00526-7 PG 8 WC Thermodynamics; Chemistry, Analytical; Chemistry, Physical SC Thermodynamics; Chemistry GA 152FX UT WOS:000077766600011 ER PT J AU Buckley, SG Damm, CJ Vitovec, WM Sgro, LA Sawyer, RF Koshland, CP Lucas, D AF Buckley, SG Damm, CJ Vitovec, WM Sgro, LA Sawyer, RF Koshland, CP Lucas, D TI Ammonia detection and monitoring with photofragmentation fluorescence SO APPLIED OPTICS LA English DT Article ID 193 NM PHOTOLYSIS; FRAGMENTATION-FLUORESCENCE; 2-PHOTON FORMATION; LASER; STATE; NACL; COAL; NH3 AB Excimer laser fragmentation-fluorescence spectroscopy is an effective detection strategy for NH3 in combustion exhausts at atmospheric pressure and high temperatures. Two-photon photofragmentation of NH3 with 193-nm light yields emission from the NW(A-X) band at 336 nm. There are no major interferences in this spectral region, and the sensitivity is at the parts per billion (ppb) level. Quenching of the NH(A) state radical by the major combustion products is measured and does not limit the applicability of the detection method. Detection limits in practical situations are of the order of 100 ppb for a 100-shot (1-s) average. This technique could prove useful in monitoring ammonia emissions from catalytic and noncatalytic NOx reduction processes involving ammonia injection. (C) 1998 Optical Society of America. C1 Univ Calif Berkeley, Dept Mech Engn, Berkeley, CA 94720 USA. Univ Calif Berkeley, Sch Publ Hlth, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Environm Energy Technol Div, Berkeley, CA 94720 USA. RP Buckley, SG (reprint author), Univ Calif Berkeley, Dept Mech Engn, Berkeley, CA 94720 USA. RI Sawyer, Robert/B-5013-2014 NR 26 TC 19 Z9 19 U1 1 U2 7 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0003-6935 J9 APPL OPTICS JI Appl. Optics PD DEC 20 PY 1998 VL 37 IS 36 BP 8382 EP 8391 DI 10.1364/AO.37.008382 PG 10 WC Optics SC Optics GA 150XA UT WOS:000077690300013 PM 18301663 ER PT J AU Bautista, MA Kallman, TR Angelini, L Liedahl, DA Smits, DP AF Bautista, MA Kallman, TR Angelini, L Liedahl, DA Smits, DP TI Hydrogen-like ion emission in the spectra of low-mass X-ray binaries SO ASTROPHYSICAL JOURNAL LA English DT Article DE atomic processes; binaries : close; X-rays : stars ID RECOMBINATION-LINE-INTENSITIES; CASE-B CALCULATIONS; COEFFICIENTS AB We study the emission from H-like ions, particularly oxygen and neon, observed in ASCA spectra of low-mass X-ray binaries (LMXBs). The observed strengths of Ly alpha emission lines relative to the recombination continua differ from the classical recombination model. This suggests a different excitation mechanism for the lines. Various mechanisms are considered, which include three-body recombination, collisional excitation, recombination satellite line emission, and resonant fluorescent excitation. We find that the detection of Lyman recombination continuum implies that the plasma is photoionized, in agreement with previous studies by Hatchett, Buff, & McCray and Liedahl & Paerels. Under collisional ionization conditions, on the other hand, the Lyman continuum should be negligible unless the temperature were greater than 3 x 10(6) K. Otherwise, the enhancement of Ly alpha emission with respect to the continuum may be due to (1) three-body recombination at electron densities greater than 10(17) cm(-3) and temperatures below 2 x 10(5) K, (2) contributions to the recombination spectrum from collisional excitation of the H-like ionization stage, (3) contributions to recombination Ly alpha emission from satellite lines due to recombination onto the He-like ionization stage, and (4) contributions to the recombination spectrum from resonant fluorescence excitation of the H-like ionization stage. Further observations of higher order Lyman series lines and lines from other ionization stages are suggested to discriminate between the various excitation mechanisms. In addition, the implications of the different spectral formation mechanisms to the hydrodynamic accretion model of LMXBs are discussed. C1 NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Greenbelt, MD 20771 USA. Univ Calif Lawrence Livermore Natl Lab, Dept Phys & Space Technol, Livermore, CA 94550 USA. HartRAO, ZA-1740 Krugersdrop, South Africa. RP Bautista, MA (reprint author), NASA, Goddard Space Flight Ctr, High Energy Astrophys Lab, Greenbelt, MD 20771 USA. NR 27 TC 15 Z9 15 U1 1 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD DEC 20 PY 1998 VL 509 IS 2 BP 848 EP 855 DI 10.1086/306516 PN 1 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 178DH UT WOS:000079250700032 ER PT J AU Peebles, DE Peebles, HC Ohlhausen, JA AF Peebles, DE Peebles, HC Ohlhausen, JA TI Kinetics of the isothermal spreading of tin on the air-passivated copper surface in the absence of a fluxing agent SO COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS LA English DT Article DE copper; tin; solder; spreading; kinetics ID X-RAY PHOTOELECTRON; THIN-FILMS; LIQUID-METALS; OXIDATION; OXYGEN; ALLOYS; ADSORPTION; XPS; CU; DIFFERENTIATION AB A specially designed ultrahigh vacuum in situ surface analysis and wetting system has been constructed to study the spreading of liquid metal solders on carefully prepared and well-characterized solid substrates, initial studies have been completed for the spreading of pure Sn solder on Cu substrates in the absence of any fluxing agent, Surface chemical analysis by X-ray photoelectron spectroscopy showed the as-received surface consisted of about 8 nm of Cu2O. Solder spreading was performed under 50 Torr of highly purified He gas to allow for adequate thermal coupling between the solder and the substrate. Isothermal spreading experiments were performed on the as-received Cu surface in the temperature range between 262 and 372 degrees C. Measurable solder spreading was observed on this surface even at temperatures only 30 degrees C above the melting temperature of the purl Sn solder (232 degrees C). The results of the isothermal experiments show that solder spreading on the as-received Cu surface is an activated process with an activation energy of 39.9 +/- 3.1 kcal mol(-1) in the range of 262 to 327 degrees C, and a 1/3-order dependence on spreading time. Between 327 degrees C and 330 degrees C. a discontinuity in the Arrhenius plot is observed. At 330 degrees C: and above, the spreading process is non-activated and shows a 1/5-order dependence on spreading time. It is believed that this discontinuity in spreading rates is a direct result of vacuum-assisted decomposition of the surface Cu2O, with retention of a subsurface oxide. Similar experiments in an inert atmosphere glove box at atmospheric pressure do not show the spreading rate discontinuity, although overall spreading rates and kinetics art: similar. The overall spreading process is believed to be facilitate ci through an oxide displacement reaction, where the spreading Sn reduces the surface Cu2O to Cu and captures the oxygen to form SnO2 as spreading proceeds. Metallurgical cross-section analysis after spreading on the as-received surface shows the expected formation of Cu-Sn intermetallic zones and a microstructure with no gaps at the Cu-Sn interface due to remaining patches of Cu oxide. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Peebles, DE (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 44 TC 17 Z9 17 U1 1 U2 10 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0927-7757 J9 COLLOID SURFACE A JI Colloid Surf. A-Physicochem. Eng. Asp. PD DEC 20 PY 1998 VL 144 IS 1-3 BP 89 EP 114 DI 10.1016/S0927-7757(98)00644-X PG 26 WC Chemistry, Physical SC Chemistry GA 151VB UT WOS:000077740400011 ER PT J AU Klemm, RA AF Klemm, RA TI What is the symmetry of the high-T-c order parameter? SO INTERNATIONAL JOURNAL OF MODERN PHYSICS B LA English DT Article; Proceedings Paper CT 1st International Conference on New Theories, Discoveries, and Applications of Superconductors and Related Materials (New3SC-1) CY FEB 19-24, 1998 CL BATON ROUGE, LOUISIANA ID <001>-TWIST GRAIN-BOUNDARIES; BI2SR2CACU2O8+DELTA BICRYSTALS; SUPERCONDUCTING GAP; PAIRING SYMMETRY; NORMAL-STATE; YBA2CU3O7-DELTA; AXIS; SURFACE; PB; TL2BA2CUO6+DELTA AB In recent years, there has been a raging controversy regarding the orbital symmetry of the superconducting order parameter (OP) in the high temperature superconductors. Many experiments were interpreted in terms of a d(x2)-(y2)-wave OP, but many others were interpreted in terms of a more conventional s-wave OP. We review the problems of both intrinsic and extrinsic natures with the phase-sensitive experiments on YBCO. We further show that the photoemission experiments of the purported superconducting gap in Bi2Sr2CaCu2O8+delta are entirely consistent with charge- and/or spin-density wave formation in that material. The presence of such density waves greatly complicates the analysis of most experiments. Hence, we conclude that the orbital symmetry of the superconducting OP is still unknown in any of the high temperature superconductors. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Klemm, RA (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 57 TC 27 Z9 28 U1 0 U2 0 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA JOURNAL DEPT PO BOX 128 FARRER ROAD, SINGAPORE 912805, SINGAPORE SN 0217-9792 J9 INT J MOD PHYS B JI Int. J. Mod. Phys. B PD DEC 20 PY 1998 VL 12 IS 29-31 BP 2920 EP 2931 DI 10.1142/S0217979298001782 PG 12 WC Physics, Applied; Physics, Condensed Matter; Physics, Mathematical SC Physics GA 175UT UT WOS:000079114500008 ER PT J AU Cai, ZX Welch, DO Dubey, GS AF Cai, ZX Welch, DO Dubey, GS TI Isothermal elastic constants of flux-line lattice in layered superconductors SO INTERNATIONAL JOURNAL OF MODERN PHYSICS B LA English DT Article; Proceedings Paper CT 1st International Conference on New Theories, Discoveries, and Applications of Superconductors and Related Materials (New3SC-1) CY FEB 19-24, 1998 CL BATON ROUGE, LA ID MONTE-CARLO SIMULATION; BI2SR2CACU2O8 CRYSTALS; IRREVERSIBILITY LINE; VORTEX-LATTICE; MODEL AB A model of the effective interaction between the magnetic flux-lines in a layered superconductor is derived from the Lawrence-Doniach model. We show analytically that the intralayer interaction energy can be evaluated using the Ewald summation technique. The melting of flux line lattices is studied using Langevin dynamics simulation of the model with various values of interlayer coupling strength and pinning intensities. The thermal fluctuation terms of the isothermal shear modulus are found to increase sharply at the melting transition temperature for systems with or without pinning, while the structural order parameters were close to zero at all temperatures for systems with strong Dinning. The melting of the Dinned flux-line lattice is discussed in the context of its elastic properties. C1 Brookhaven Natl Lab, Div Mat Sci, Upton, NY 11973 USA. CUNY Hunter Coll, New York, NY 10021 USA. RP Brookhaven Natl Lab, Div Mat Sci, Upton, NY 11973 USA. NR 20 TC 0 Z9 0 U1 0 U2 0 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA 5 TOH TUCK LINK, SINGAPORE 596224, SINGAPORE SN 0217-9792 EI 1793-6578 J9 INT J MOD PHYS B JI Int. J. Mod. Phys. B PD DEC 20 PY 1998 VL 12 IS 29-31 BP 2974 EP 2981 DI 10.1142/S0217979298001897 PG 8 WC Physics, Applied; Physics, Condensed Matter; Physics, Mathematical SC Physics GA 175UT UT WOS:000079114500019 ER PT J AU Janko, B Kosztin, I Levin, K AF Janko, B Kosztin, I Levin, K TI Pseudogap regime in a BCS Bose-Einstein crossover scenario: Experimental consequences and tests SO INTERNATIONAL JOURNAL OF MODERN PHYSICS B LA English DT Article; Proceedings Paper CT 1st International Conference on New Theories, Discoveries, and Applications of Superconductors and Related Materials (New3SC-1) CY FEB 19-24, 1998 CL BATON ROUGE, LOUISIANA ID T-C SUPERCONDUCTORS; CUPRATE SUPERCONDUCTORS; MAGNETIC-SUSCEPTIBILITY; NORMAL-STATE; BI2SR2CACU2O8+DELTA; SPECTROSCOPY; JUNCTIONS; GAP AB We have argued that the pseudogap regime in the cuprates is characterized by the presence of metastable, long lived pairs which form the natural intermediate state between the free fermions of the BCS and bound pairs of the Bose Einstein limits. Here we investigate the experimental consequences associated with this resonant pair scattering in the normal state. The essential feature of these pair resonances is that they are dynamic pairing fluctuations. Of particular interest in distinguishing different scenarios for the cuprate pseudogap are probes which predominantly couple to the static and dynamic pair fluctuations, respectively. We therefore contrast the behavior of the diamagnetic susceptibility with the pair tunneling spectra of Superconductor-Pseudogapped cuprate junctions. C1 Univ Chicago, James Franck Inst, Chicago, IL 60637 USA. RP Janko, B (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 35 TC 2 Z9 2 U1 0 U2 0 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA JOURNAL DEPT PO BOX 128 FARRER ROAD, SINGAPORE 912805, SINGAPORE SN 0217-9792 J9 INT J MOD PHYS B JI Int. J. Mod. Phys. B PD DEC 20 PY 1998 VL 12 IS 29-31 BP 3009 EP 3015 DI 10.1142/S0217979298001964 PG 7 WC Physics, Applied; Physics, Condensed Matter; Physics, Mathematical SC Physics GA 175UT UT WOS:000079114500026 ER PT J AU Naugle, DG Rathnayaka, KDD Canfield, PC AF Naugle, DG Rathnayaka, KDD Canfield, PC TI Metamagnetic phases and interplay with superconductivity of single crystal DyNi2B2C SO INTERNATIONAL JOURNAL OF MODERN PHYSICS B LA English DT Article; Proceedings Paper CT 1st International Conference on New Theories, Discoveries, and Applications of Superconductors and Related Materials (New3SC-1) CY FEB 19-24, 1998 CL BATON ROUGE, LOUISIANA ID HONI2B2C; ORDER AB DyNi2B2C with T-c similar to 6 K, less than the Neel temperature T-N, is particularly interesting. Crystal electric field splitting locks the magnetic moments in the ab-plane at low temperature and a series of metamagnetic transitions is observed with increasing field below TN. Detailed measurements of in-plane magnetization, magnetic susceptibility and resistivity of DyNi2B2C single crystals have been carried out in order to investigate the anisotropic interplay between superconductivity and the magnetic phases. C1 Texas A&M Univ, Dept Phys, College Stn, TX 77843 USA. Iowa State Univ Sci & Technol, Dept Phys, Ames, IA 50011 USA. Ames Lab, Ames, IA 50011 USA. RP Naugle, DG (reprint author), Texas A&M Univ, Dept Phys, College Stn, TX 77843 USA. RI Canfield, Paul/H-2698-2014 NR 8 TC 2 Z9 2 U1 0 U2 2 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA JOURNAL DEPT PO BOX 128 FARRER ROAD, SINGAPORE 912805, SINGAPORE SN 0217-9792 J9 INT J MOD PHYS B JI Int. J. Mod. Phys. B PD DEC 20 PY 1998 VL 12 IS 29-31 BP 3174 EP 3178 DI 10.1142/S0217979298002283 PG 5 WC Physics, Applied; Physics, Condensed Matter; Physics, Mathematical SC Physics GA 175UT UT WOS:000079114500058 ER PT J AU Almasan, CC Levin, GA Cimpoiasu, E Stein, T Gajewski, DA Maple, MB Zheng, H Paulikas, AP Veal, BW AF Almasan, CC Levin, GA Cimpoiasu, E Stein, T Gajewski, DA Maple, MB Zheng, H Paulikas, AP Veal, BW TI Out-of-plane and in-plane conduction in insulating and strongly underdoped cuprates SO INTERNATIONAL JOURNAL OF MODERN PHYSICS B LA English DT Article; Proceedings Paper CT 1st International Conference on New Theories, Discoveries, and Applications of Superconductors and Related Materials (New3SC-1) CY FEB 19-24, 1998 CL BATON ROUGE, LOUISIANA ID RESISTIVITY AB We report measurements of out-of-plane (rho(c)) and in-plane (rho(ab)) normal-state resistivities of single crystals of insulating PrBa2Cu3O7-delta and strongly underdoped oxygen deficient YBa2Cu3O6.41 using a flux transformer method. In the superconducting specimens, the onset of superconductivity was suppressed by a magnetic field of 9 T. We have found that the anisotropy rho(c)/rho(ab) of these samples increases monotonically at low temperatures with no signs of saturation. The temperature dependence of rho(c)/rho(ab) for YBa2Cu3O6.41 is well described by rho(c)/rho(ab) = a + bT(-2/3), but over a smaller temperature range than for insulating PrBa2Cu3O7-delta. Both the absence of saturation of rho(c)/rho(ab) and its T-2/3 dependence indicate two-dimensional conduction. This means that the average in-plane hopping distance of the localized charge carriers increases with decreasing T according to Mott's (R) over bar similar to T-1/3 law, while the elementary step in the c-direction remains T independent, equal to the spacing between the bilayers. C1 Kent State Univ, Dept Phys, Kent, OH 44242 USA. Univ Calif San Diego, Dept Phys, La Jolla, CA 92093 USA. Univ Calif San Diego, Inst Pure & Appl Phys Sci, La Jolla, CA 92093 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Almasan, CC (reprint author), Kent State Univ, Dept Phys, Kent, OH 44242 USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA JOURNAL DEPT PO BOX 128 FARRER ROAD, SINGAPORE 912805, SINGAPORE SN 0217-9792 J9 INT J MOD PHYS B JI Int. J. Mod. Phys. B PD DEC 20 PY 1998 VL 12 IS 29-31 BP 3203 EP 3206 DI 10.1142/S0217979298002325 PG 4 WC Physics, Applied; Physics, Condensed Matter; Physics, Mathematical SC Physics GA 175UT UT WOS:000079114500062 ER PT J AU Sarrao, JL AF Sarrao, JL TI Structural, magnetic and transport properties of Li-doped La(2)Cuo(4) SO INTERNATIONAL JOURNAL OF MODERN PHYSICS B LA English DT Article; Proceedings Paper CT 1st International Conference on New Theories, Discoveries, and Applications of Superconductors and Related Materials (New3SC-1) CY FEB 19-24, 1998 CL BATON ROUGE, LOUISIANA ID LA2CU1-XLIXO4; LA2CU0.5LI0.5O4; SINGLET; TEXTURE; STATES; SPIN AB We review recent work on La2Cu1-xLixO4 for 0 < x < 0.5. Li substitutes for Cu in La2CuO4, resulting in both the addition of a hole and the loss of a spin (because Li is monovalent and S = 0 while Cu is divalent and S = 1/2). Qualitatively, Li substitution has the same effect as the combined substitution of Sr and Zn. We explore the extent to which this analogy can be made quantitative and discuss how these results influence our understanding of the doped hole state in La2CuO4. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Sarrao, JL (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 19 TC 0 Z9 0 U1 0 U2 0 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA JOURNAL DEPT PO BOX 128 FARRER ROAD, SINGAPORE 912805, SINGAPORE SN 0217-9792 J9 INT J MOD PHYS B JI Int. J. Mod. Phys. B PD DEC 20 PY 1998 VL 12 IS 29-31 BP 3224 EP 3227 DI 10.1142/S0217979298002362 PG 4 WC Physics, Applied; Physics, Condensed Matter; Physics, Mathematical SC Physics GA 175UT UT WOS:000079114500066 ER PT J AU Cooley, JC Hults, WL Peterson, EJ Smith, JL AF Cooley, JC Hults, WL Peterson, EJ Smith, JL TI PrBa2Cu3Ox superconducting powders SO INTERNATIONAL JOURNAL OF MODERN PHYSICS B LA English DT Article; Proceedings Paper CT 1st International Conference on New Theories, Discoveries, and Applications of Superconductors and Related Materials (New3SC-1) CY FEB 19-24, 1998 CL BATON ROUGE, LOUISIANA ID MAGNETIC-PROPERTIES; PR; BAPRO3 AB We have been preparing polycrystalline PrBa2Cu3Ox (PBCO) to look for superconductivity at 89 K as has been reported in single crystals and thin films. We have found two transitions one at approximate to 90 K and another one at approximate to 12 K in samples, which we are still unable to make single phase. Additional phases include PrBaO3 and BaCuO2. The PBCO samples all appear to have the usual YBCO crystal structure and this is the phase that we believe contains the approximate to 90 K transition. The approximate to 12 K transition is most likely antiferromagnetic ordering of the PrBaO3 phase. We are continuing to investigate sample preparation. Here we present and discuss the superconducting and magnetic properties of our samples. C1 Univ Calif Los Alamos Natl Lab, Superconduct Technol Ctr, Los Alamos, NM 87545 USA. RP Cooley, JC (reprint author), Univ Calif Los Alamos Natl Lab, Superconduct Technol Ctr, Mail Stop K763, Los Alamos, NM 87545 USA. RI Cooley, Jason/E-4163-2013 NR 15 TC 9 Z9 9 U1 1 U2 4 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA JOURNAL DEPT PO BOX 128 FARRER ROAD, SINGAPORE 912805, SINGAPORE SN 0217-9792 J9 INT J MOD PHYS B JI Int. J. Mod. Phys. B PD DEC 20 PY 1998 VL 12 IS 29-31 BP 3254 EP 3258 DI 10.1142/S0217979298002416 PG 5 WC Physics, Applied; Physics, Condensed Matter; Physics, Mathematical SC Physics GA 175UT UT WOS:000079114500071 ER PT J AU du Mar, AC Rathnayaka, KDD Naugle, DG Canfield, PC AF du Mar, AC Rathnayaka, KDD Naugle, DG Canfield, PC TI Anisotropic upper critical field of single crystal RNi2B2C (R = Y, Lu) SO INTERNATIONAL JOURNAL OF MODERN PHYSICS B LA English DT Article; Proceedings Paper CT 1st International Conference on New Theories, Discoveries, and Applications of Superconductors and Related Materials (New3SC-1) CY FEB 19-24, 1998 CL BATON ROUGE, LOUISIANA ID LUNI2B2C; TRANSPORT AB Measurements of the anisotropic upper critical held curves have been extended for YNi2B2C and LuNi2B2C (T-c = 15.6 K and 16.1 K, respectively). Measurements of R(T, H) were taken along the crystallographic directions of [100] and [110]. The resulting critical fields show an upward curvature near Te and a linear behavior at low temperature, which continues to below 2 K with little, if any, sign of saturation. C1 Texas A&M Univ, Dept Phys, College Stn, TX 77843 USA. Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Dept Phys & Astron, Ames, IA 50011 USA. RP du Mar, AC (reprint author), Texas A&M Univ, Dept Phys, College Stn, TX 77843 USA. RI Canfield, Paul/H-2698-2014 NR 9 TC 10 Z9 10 U1 0 U2 0 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA JOURNAL DEPT PO BOX 128 FARRER ROAD, SINGAPORE 912805, SINGAPORE SN 0217-9792 J9 INT J MOD PHYS B JI Int. J. Mod. Phys. B PD DEC 20 PY 1998 VL 12 IS 29-31 BP 3264 EP 3266 DI 10.1142/S021797929800243X PG 3 WC Physics, Applied; Physics, Condensed Matter; Physics, Mathematical SC Physics GA 175UT UT WOS:000079114500073 ER PT J AU Hults, WL Cooley, JC Peterson, EJ Smith, JL Blackstead, HA Dow, JD AF Hults, WL Cooley, JC Peterson, EJ Smith, JL Blackstead, HA Dow, JD TI PrBa2Cu3Ox polycrystalline superconductor preparation SO INTERNATIONAL JOURNAL OF MODERN PHYSICS B LA English DT Article; Proceedings Paper CT 1st International Conference on New Theories, Discoveries, and Applications of Superconductors and Related Materials (New3SC-1) CY FEB 19-24, 1998 CL BATON ROUGE, LOUISIANA ID BA-CU-O; NEUTRON-DIFFRACTION; MAGNETIC-PROPERTIES; PR; SYSTEM; BAPRO3 AB We prepared many samples of nominal PrBa2Cu3Ox as ceramic, polycrystalline pellets with an enormous variety of preparation conditions and can confirm its superconductivity at T-c = 89 K. We found that the superconductivity is in material with the YBa2Cu3O7 (YBCO) crystal structure. We observed weak ferromagnetism (canted antiferromagnetism) in samples prepared at high temperatures with a low partial pressure of oxygen; these samples also contained the phase PrBaO3. The electromagnetic properties of the material depend sensitively on preparation conditions, especially the sintering temperature and the oxygen level. C1 Univ Calif Los Alamos Natl Lab, Superconduct Technol Ctr, Los Alamos, NM 87545 USA. Univ Notre Dame, Dept Phys, Notre Dame, IN 46556 USA. Arizona State Univ, Dept Phys, Tempe, AZ 85287 USA. Natl High Magnet Field Lab, Tallahassee, FL 32306 USA. RP Hults, WL (reprint author), Univ Calif Los Alamos Natl Lab, Superconduct Technol Ctr, Mail Stop K763, Los Alamos, NM 87545 USA. RI Cooley, Jason/E-4163-2013 NR 20 TC 14 Z9 14 U1 1 U2 3 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA JOURNAL DEPT PO BOX 128 FARRER ROAD, SINGAPORE 912805, SINGAPORE SN 0217-9792 J9 INT J MOD PHYS B JI Int. J. Mod. Phys. B PD DEC 20 PY 1998 VL 12 IS 29-31 BP 3278 EP 3283 DI 10.1142/S0217979298002465 PG 6 WC Physics, Applied; Physics, Condensed Matter; Physics, Mathematical SC Physics GA 175UT UT WOS:000079114500076 ER PT J AU Pessaud, S De Sousa, D Lobo, R Gervais, F AF Pessaud, S De Sousa, D Lobo, R Gervais, F TI Extended-drude model to fit infrared conductivity cuprate laser-ablated films SO INTERNATIONAL JOURNAL OF MODERN PHYSICS B LA English DT Article; Proceedings Paper CT 1st International Conference on New Theories, Discoveries, and Applications of Superconductors and Related Materials (New3SC-1) CY FEB 19-24, 1998 CL BATON ROUGE, LOUISIANA ID LA2-XSRXCUO4 AB An "extended-Drude" model, implying a simple form for the self-energy function of the mobile charge-carrier response, has been applied to fitting the infrared and visible reflectivity spectra of simple cuprates. Excellent fits are obtained in a wide spectral range, from 4 meV to 4 eV, with a very restricted number of adjustable parameters. The optical conductivity obtained with this procedure is highly different from the Kramers-Kronig transformation of reflectivity spectra. The same procedure has been applied to characterise the infrared conductivity of multi-target laser-ablated films built via intergrowth of YBa2Cu3O7 and MCuO2 (M = Ca, Sr). C1 CNRS, Ctr Rech Phys Hautes Temp, F-45071 Orleans, France. Brookhaven Natl Lab, Upton, NY 11793 USA. Univ Tours, Fac Sci & Tech, Lab Electrodynam Mat Avances, F-37200 Tours, France. RP Pessaud, S (reprint author), CNRS, Ctr Rech Phys Hautes Temp, F-45071 Orleans, France. OI Lobo, Ricardo/0000-0003-2355-6856 NR 6 TC 1 Z9 1 U1 1 U2 2 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA JOURNAL DEPT PO BOX 128 FARRER ROAD, SINGAPORE 912805, SINGAPORE SN 0217-9792 J9 INT J MOD PHYS B JI Int. J. Mod. Phys. B PD DEC 20 PY 1998 VL 12 IS 29-31 BP 3323 EP 3325 DI 10.1142/S0217979298002556 PG 3 WC Physics, Applied; Physics, Condensed Matter; Physics, Mathematical SC Physics GA 175UT UT WOS:000079114500085 ER PT J AU Gor'kov, LP Kresin, VZ AF Gor'kov, LP Kresin, VZ TI Band and percolation approaches to low temperature properties of manganites SO INTERNATIONAL JOURNAL OF MODERN PHYSICS B LA English DT Article; Proceedings Paper CT 1st International Conference on New Theories, Discoveries, and Applications of Superconductors and Related Materials (New3SC-1) CY FEB 19-24, 1998 CL BATON ROUGE, LOUISIANA ID LA1-XSRXMNO3; MAGNETORESISTANCE; TRANSITION AB Properties of the parent compound, LaMnO3 are greatly affected by strong Hund's coupling. Assuming the antiferromagnetic ordering (with a low Neel temperature) along one of the cubic axes, this coupling would result in formation of disconnected ferromagnetic layers. Furthermore, in the presence of the cooperative Jahn-Teller effect the compound becomes a band insulator. At small doping (La1-xCaxMnO3, x much less than 1) the band insulator phase coexists with the presence of localized holes. An insulator-ferromagnetic metal transition occurs at the percolation point x(c) = 0.16. C1 Florida State Univ, Natl High Magnet Field Lab, Tallahassee, FL 32310 USA. LD Landau Theoret Phys Inst, Moscow, Russia. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Gor'kov, LP (reprint author), Florida State Univ, Natl High Magnet Field Lab, Tallahassee, FL 32310 USA. NR 24 TC 0 Z9 0 U1 0 U2 0 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA JOURNAL DEPT PO BOX 128 FARRER ROAD, SINGAPORE 912805, SINGAPORE SN 0217-9792 J9 INT J MOD PHYS B JI Int. J. Mod. Phys. B PD DEC 20 PY 1998 VL 12 IS 29-31 BP 3349 EP 3354 DI 10.1142/S0217979298002623 PG 6 WC Physics, Applied; Physics, Condensed Matter; Physics, Mathematical SC Physics GA 175UT UT WOS:000079114500092 ER PT J AU Gervais, F Daulan, C Maignan, A Lobo, RPSM AF Gervais, F Daulan, C Maignan, A Lobo, RPSM TI Non-conventional infrared conductivity of La2CuO4.06 and Pr0.7Sr0.2Ca0.1MnO3 SO INTERNATIONAL JOURNAL OF MODERN PHYSICS B LA English DT Article; Proceedings Paper CT 1st International Conference on New Theories, Discoveries, and Applications of Superconductors and Related Materials (New3SC-1) CY FEB 19-24, 1998 CL BATON ROUGE, LOUISIANA ID MAGNETORESISTANCE AB Pr0.7Sr0.2Ca0.1MnO3 displays a ferromagnetic metallic-like to non-ferromagnetic insulator-like phase transition near 200 K and shows colossal magneto-resistance. The temperature evolution of its optical conductivity was measured and the results were compared to those of La2CuO4.06 which is a superconductor below 34 K. The growth of a peak in the conductivity around 10 meV upon cooling Pr0.7Sr0.2Ca0.1MnO3 strongly suggests a trapped-polaron contribution to the conductivity. C1 Univ Tours, Lab Electrodynam Mat Avances, F-37200 Tours, France. Inst Sci Mat & Rayonnement, CRISMAT, Unite Mixte Rech 6508, F-14050 Caen, France. Brookhaven Natl Lab, Univ Florida, Dept Phys, Upton, NY 11793 USA. RP Gervais, F (reprint author), Univ Tours, Lab Electrodynam Mat Avances, F-37200 Tours, France. OI Lobo, Ricardo/0000-0003-2355-6856 NR 13 TC 3 Z9 3 U1 0 U2 0 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA JOURNAL DEPT PO BOX 128 FARRER ROAD, SINGAPORE 912805, SINGAPORE SN 0217-9792 J9 INT J MOD PHYS B JI Int. J. Mod. Phys. B PD DEC 20 PY 1998 VL 12 IS 29-31 BP 3393 EP 3396 DI 10.1142/S0217979298002726 PG 4 WC Physics, Applied; Physics, Condensed Matter; Physics, Mathematical SC Physics GA 175UT UT WOS:000079114500102 ER PT J AU Alvarez, RJ Senff, CJ Hardesty, RM Parrish, DD Luke, WT Watson, TB Daum, PH Gillani, N AF Alvarez, RJ Senff, CJ Hardesty, RM Parrish, DD Luke, WT Watson, TB Daum, PH Gillani, N TI Comparisons of airborne lidar measurements of ozone with airborne in situ measurements during the 1995 Southern Oxidants Study SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID TROPOSPHERIC OZONE; DIAL MEASUREMENTS; AEROSOL PROFILES; SYSTEM; RANGE AB As part of the 1995 Southern Oxidants Study (SOS), the National Oceanic and Atmospheric Administration airborne ozone lidar was deployed during June and July to provide detailed three-dimensional lower tropospheric ozone distribution information in the Nashville, Tennessee, area. The airborne portion of the study included six aircraft instrumented with an assortment of in situ and remote sensors. Results of comparisons between the ozone values obtained using the lidar and the values obtained using in situ instrumentation aboard other aircraft are presented. High resolution (90 m vertical and 520 m horizontal corresponding to 8 s at a flight speed of 65 m/s) was maintained during the analysis of the lidar data which caused statistical variations in the calculated ozone concentrations from 3 ppbv (5% for typical ozone concentrations encountered during the study) at a range of 1500 m from the lidar to 11 ppbv (17%) at a range of 2500 m from the lidar. However, the lidar ozone concentration measurements compare favorably with the in situ values, with the average offset less than 10 ppbv (16%) for each flight, and the average magnitude of the offsets over all the flights at 4.3 ppbv (7%). C1 NOAA, ETL, MS, Environm Res Lab, Boulder, CO 80303 USA. US DOE, Brookhaven Natl Lab, Upton, NY 11973 USA. Univ Alabama, Earth Syst Sci Lab, Huntsville, AL 35899 USA. NOAA, ERL, Air Resources Lab, Silver Spring, MD 20910 USA. NOAA, Aeron Lab, ERL, Boulder, CO 80303 USA. NOAA, ERL, Air Resources Lab, Idaho Falls, ID 83401 USA. RP Alvarez, RJ (reprint author), NOAA, ETL, MS, Environm Res Lab, 325 Broadway,R-E-ET2, Boulder, CO 80303 USA. EM ralvarez@ctl.noaa.gov RI Parrish, David/E-8957-2010; Hardesty, Robert/H-9844-2013; Senff, Christoph/I-2592-2013; Alvarez, Raul/I-4879-2013; Luke, Winston/D-1594-2016 OI Parrish, David/0000-0001-6312-2724; Luke, Winston/0000-0002-1993-2241 NR 24 TC 18 Z9 18 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD DEC 20 PY 1998 VL 103 IS D23 BP 31155 EP 31171 DI 10.1029/98JD02745 PG 17 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 154GM UT WOS:000077880800011 ER PT J AU Larsen, FH Jakobsen, HJ Ellis, PD Nielsen, NC AF Larsen, FH Jakobsen, HJ Ellis, PD Nielsen, NC TI High-field QCPMG-MAS NMR of half-integer quadrupolar nuclei with large quadrupole couplings SO MOLECULAR PHYSICS LA English DT Article ID ANGLE-SPINNING NMR; PRINCIPAL-AXIS SYSTEMS; SOLID-STATE NMR; RELATIVE ORIENTATION; DOUBLE-ROTOR; MAGNETIC-RESONANCE; SHIELDING TENSORS; RUBIDIUM SALTS; NUTATION NMR; SPECTROSCOPY AB The quadrupole Carr-Purcell-Meiboom-Gill NMR experiment using magic-angle spinning (QCPMG-MAS) is analysed as a means of determining quadrupolar coupling and anisotropic chemical shielding tensors for half-integer (I > 1/2) quadrupolar nuclei with large quadrupole coupling constants (C-Q) This is accomplished by numerical simulations and Rb-87 NMR experiments wih Rb2SO4 and Rb2CrO4 using different magnetic fields. It is demonstrated that (i) QCPMG-MAS experiments typically provide a sensitivity gain by more than an order of magnitude relative to quadrupolar-echo MAS experiments, (ii) non-secular second-order terms do not affect the spin evolution appreciably, and (iii) the effect of finite RF pulses needs to be considered when 2 omega(Q)(2) /(omega(0)omega(RF)) > 0 1, where omega(Q) = 2 pi C-Q/(4I(2I-1)), omega(RF) is the RF amplitude, and omega(0) the Larmor frequency. Using numerical simulations and iterative fitting the magnitudes and relative orientation of Rb-87 quadrupolar coupling and chemical shielding tensors for Rb2SO4 and Rb2CrO4 have been determined. C1 Aarhus Univ, Dept Chem, Instrument Ctr Solid State NMR Spect, DK-8000 Aarhus C, Denmark. Pacific NW Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Larsen, FH (reprint author), Aarhus Univ, Dept Chem, Instrument Ctr Solid State NMR Spect, DK-8000 Aarhus C, Denmark. RI Larsen, Flemming/A-5255-2015 OI Larsen, Flemming/0000-0001-5180-6870 NR 36 TC 44 Z9 45 U1 2 U2 18 PU TAYLOR & FRANCIS LTD PI LONDON PA ONE GUNPOWDER SQUARE, LONDON EC4A 3DE, ENGLAND SN 0026-8976 J9 MOL PHYS JI Mol. Phys. PD DEC 20 PY 1998 VL 95 IS 6 BP 1185 EP 1195 DI 10.1080/002689798166206 PG 11 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 153WY UT WOS:000077857300012 ER PT J AU Patnaik, S Budhani, RC Wang, YL Suenaga, M AF Patnaik, S Budhani, RC Wang, YL Suenaga, M TI Radio frequency vortex dynamics in oriented platelets of (Bi-Pb)(2)Sr2Ca2Cu3O10 superconductor SO PHYSICA C LA English DT Article DE radio frequency; vortex dynamics; lorentz force ID HIGH-TEMPERATURE SUPERCONDUCTORS; BI2SR2CACU2O8+DELTA SINGLE-CRYSTALS; LOCK-IN TRANSITION; BA-CU-O; II SUPERCONDUCTORS; PENETRATION DEPTH; THIN-FILMS; CRITICAL CURRENTS; MAGNETIC-FIELDS; FLUX CREEP AB We report measurements of temperature and field dependence of the radio frequency (rf) penetration depth lambda(H,T) in oriented platelets of (Bi-Pb)(2)Sr2Ca2Cu3O10 superconductor. For the DC field aligned perpendicular to the plane of the platelet (predominantly H parallel to c configuration), three distinct regimes of field variation of lambda(H,T) are identified which correspond, respectively to grain boundary/weak link pinning, intragrain pinning and flux flow with the increasing field. In the low flux density regime investigated here, lambda(H,T) follows the dynamics of a single vortex subjected to a periodic pinning potential, a viscous damping and an oscillating Lorentz force of rf currents. The pinning force constants for H perpendicular (perpendicular to) and parallel (parallel to) to the plane of the platelet are k(p)(perpendicular to) similar to 2.2 x 10(4) N/m(2) and k(p)(parallel to) similar to 1 x 10(5) N/m(2) at 65 K, respectively for bulk pinning and are considerably lower for intergrain pinning. The force constant follows an angular dependence of the type, k(p)(perpendicular to) similar to - k(p)(phi) sin theta for phi > 8 degrees, where phi is the angle between the applied field and the plane of the platelet. The critical fields H-1* and H-2* at which the dynamics changes from grain boundary dominated to bulk pinning and from bulk pinning to flux flow are determined, and have been identified with H-c1 of the grains and irreversibility field, respectively. The trapping of flux between grain boundaries, which has eluded detection in the studies of Dt magnetization is distinctly established through these high-frequency measurements. (C) 1998 Published by Elsevier Science B.V. All rights reserved. C1 Indian Inst Technol, Dept Phys, Kanpur 208016, Uttar Pradesh, India. Brookhaven Natl Lab, Upton, NY 11973 USA. RP Budhani, RC (reprint author), Indian Inst Technol, Dept Phys, Kanpur 208016, Uttar Pradesh, India. EM rcb@iitk.emet.in NR 51 TC 4 Z9 4 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD DEC 20 PY 1998 VL 309 IS 3-4 BP 221 EP 230 DI 10.1016/S0921-4534(98)00586-3 PG 10 WC Physics, Applied SC Physics GA 151FT UT WOS:000077710600009 ER PT J AU Goretta, KC Park, ET Koritala, RE Cuber, MM Pascual, EA Chen, N de Arellano-Lopez, AR Routbort, JL AF Goretta, KC Park, ET Koritala, RE Cuber, MM Pascual, EA Chen, N de Arellano-Lopez, AR Routbort, JL TI Thermomechanical response of polycrystalline BaZrO3 SO PHYSICA C LA English DT Article DE Young's modulus; deformation rate; thermomechanical properties ID T-C SUPERCONDUCTORS; TEMPERATURE ULTRASONIC CHARACTERIZATION; NONLINEAR ACOUSTIC PROPERTIES; THERMAL-EXPANSION; NEUTRON-DIFFRACTION; O SUPERCONDUCTOR; YBA2CU3O7-X; CERAMICS; CREEP; DEFORMATION AB Thermomechanical properties of fine-grained, 96% dense, polycrystalline BaZrO3 specimens were studied. The average thermal expansion coefficient of BaZrO3 at 25-1000 degrees C was 7.72 x 10(-6)degrees C-1. At 25 degrees C, Young's modulus was 240.5 GPa and the shear modulus was 97.2 GPa. These values decreased by approximate to 10% with heating to 1015 degrees C. Poisson's ratio was 0.237 and was independent of temperature. The BaZrO3 specimens exhibited a thermal expansion coefficient of about one half, and elastic moduli more than twice, those of polycrystalline high-temperature superconductors. Diffusional creep was observed when BaZrO3 was compressed at 1300-1400 degrees C; the activation energy for steady-state deformation was 460 +/- 30 kJ/mole. The mechanism was probably grain-boundary sliding, controlled by diffusion of one of the cations along grain boundaries. Deformation rates below 1000 degrees C were too low to relax thermally generated stresses. Published by Elsevier Science B.V. C1 Argonne Natl Lab, Div Energy Technol, Argonne, IL 60439 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Univ Sevilla, Dept Fis Mat Condensada, E-41080 Seville, Spain. RP Goretta, KC (reprint author), Argonne Natl Lab, Div Energy Technol, 9700 S Cass Ave, Argonne, IL 60439 USA. EM k_goretta@qmgate.anl.gov RI Koritala, Rachel/F-1774-2011; OI R. de Arellano Lopez, Antonio/0000-0002-7443-0244 NR 42 TC 29 Z9 29 U1 0 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD DEC 20 PY 1998 VL 309 IS 3-4 BP 245 EP 250 DI 10.1016/S0921-4534(98)00588-7 PG 6 WC Physics, Applied SC Physics GA 151FT UT WOS:000077710600012 ER PT J AU Solovyov, VF Wiesmann, HJ Suenaga, M Feenstra, R AF Solovyov, VF Wiesmann, HJ Suenaga, M Feenstra, R TI Thick YBa2Cu3O7 films by post annealing of the precursor by high rate e-beam deposition on SrTiO3 substrates SO PHYSICA C LA English DT Article DE reduced oxygen; YBa2Cu3O7; high rate evaporation; SrTiO3; critical current densities ID GROWTH AB High rate evaporation techniques were used to deposit Y, BaF2, and Cu precursor films onto SrTiO3 single crystal substrates at rates in excess of 10 nm/s. Y and Cu were deposited by electron beam (e-beam) heating and thermal heating was used for BaF2. Post deposition annealing was used to form 3 mu m thick c-axis aligned YBa2Cu3O7 films on the SrTiO3 substrates, Critical current densities 1.8 x 10(5) A/cm(2) at 1 T (H parallel to c) and 77 K were achieved. The films were nominally stoichiometric and were post-deposition annealed in a humidified reduced oxygen atmosphere at 725-800 degrees C. These results indicate that the so-called BaF2 post annealing process can be one of several possible candidate methods for production of thick YBa2Cu3O7 coatings for large scale applications. (C) 1998 Published by Elsevier Science B.V. All rights reserved. C1 Brookhaven Natl Lab, Dept Appl Sci, Upton, NY 11973 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Suenaga, M (reprint author), Brookhaven Natl Lab, Dept Appl Sci, Upton, NY 11973 USA. EM mas@sun2.bnl.gov RI Solovyov, Vyacheslav/A-7724-2009; OI Solovyov, Vyacheslav/0000-0003-1879-9802 NR 15 TC 41 Z9 41 U1 1 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD DEC 20 PY 1998 VL 309 IS 3-4 BP 269 EP 274 DI 10.1016/S0921-4534(98)00526-7 PG 6 WC Physics, Applied SC Physics GA 151FT UT WOS:000077710600016 ER PT J AU Mallamaci, MP Bentley, J Carter, CB AF Mallamaci, MP Bentley, J Carter, CB TI In-situ TEM crystallization of silicate-glass films on Al2O3 SO ACTA MATERIALIA LA English DT Article ID SEEDED ALBITE GLASS; NITRIDE CERAMICS; EPITAXIAL-GROWTH; LIQUID-PHASE; ALUMINA; MORPHOLOGY; BOUNDARIES; ANORTHITE; INTERFACE AB Silicate-glass films were grown by pulsed-laser deposition on single-crystal, basal-plane Al2O3 substrates which had been pre-thinned to electron transparency. Experiments were then performed at high temperature in the TEM, which allowed direct observation and video-recording of the crystallization process. The epitactic growth of pseudo-orthorhombic anorthite: (CaAl2Si2O8) and grossular (Ca3Al2SiO12) on the basal Al2O3 surface was observed, emphasizing the role of the substrate as a "seed" for glass devitrification. The grossular crystals nucleated and grew at random on the substrate surface. In contrast, the anorthite crystals showed preferential nucleation at defect sites in the as-deposited glass film. Nucleation was followed by lateral growth along the substrate surface radiating away from the defect sites. Rotational variants for the silicate crystals were found in both cases, owing to the three-fold symmetry of the substrate. The simultaneous growth of these rotational variants on the substrate surface caused the formation of high-symmetry grain boundaries within the silicate film. In the anorthite film, these grain boundaries were often faceted parallel to low-index planes in one or both grains. (C) 1997 Acta Metallurgica Inc. C1 Univ Minnesota, Dept Chem Engn & Mat Sci, Minneapolis, MN 55455 USA. Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37381 USA. RP Mallamaci, MP (reprint author), Goodyear Tire & Rubber Co, Dept Analyt Sci, 142 Goodyear Blvd, Akron, OH 44305 USA. RI Carter, C. Barry/E-6478-2010 OI Carter, C. Barry/0000-0003-4251-9102 NR 38 TC 4 Z9 4 U1 2 U2 7 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1359-6454 J9 ACTA MATER JI Acta Mater. PD DEC 19 PY 1998 VL 46 IS 1 BP 283 EP 303 DI 10.1016/S1359-6454(97)00191-2 PG 21 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA YQ444 UT WOS:000071388100026 ER PT J AU Zhu, YT Peterson, EJ Baldonado, PS Coulter, JY Peterson, DE Mueller, FM AF Zhu, YT Peterson, EJ Baldonado, PS Coulter, JY Peterson, DE Mueller, FM TI Crystal structure and chemistry of four new RBa4Cu3O8.5+delta (R = Ho, Er, Tm and Yb) compounds SO JOURNAL OF ALLOYS AND COMPOUNDS LA English DT Article DE Ho143; Er143; Tm143; Yb143; Rietveld refinement; crystal structure; space group; cuprate ID SYSTEM AB Four new RBa4Cu3O8.5+delta (R143) compounds, where R=Ho, Er, Tm, and Yb, were synthesized from precursors Ho2O3, Er2O3 Tm2O3,Yb2O3, BaO2, and CuO at 1000 degrees C in an oxygen atmosphere. The oxygen stoichiometric value delta was found to be 0.50 for Ho143, 0.53 for Er143, 0.79 for Tm 143 and 1.01 for Yb143 by iodometric titration. Rietveld refinement of X-ray powder diffraction data showed that all the compounds belong to the space group Pm (3) over bar. The compounds have a cubic unit cell with lattice parameters of 8.09485+/-0.00007 Angstrom for Ho143, 8.08236+/-0.00005 Angstrom for Er143, 8.07670+/-0.00008 Angstrom for Tm143, and 8.06198+/-0.00005 Angstrom for Yb143. SQUID measurements indicated that none of the compounds was superconducting above 5 K. (C) 1998 Elsevier Science S.A. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. RP Peterson, DE (reprint author), Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Mail Stop K763, Los Alamos, NM 87545 USA. RI Zhu, Yuntian/B-3021-2008 OI Zhu, Yuntian/0000-0002-5961-7422 NR 13 TC 5 Z9 5 U1 1 U2 3 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0925-8388 J9 J ALLOY COMPD JI J. Alloy. Compd. PD DEC 18 PY 1998 VL 281 IS 2 BP 137 EP 145 DI 10.1016/S0925-8388(98)00798-1 PG 9 WC Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering GA 153MY UT WOS:000077837900011 ER PT J AU Chakoumakos, BC Mandrus, D AF Chakoumakos, BC Mandrus, D TI Ru3Sn7 with the Ir3Ge7 structure-type SO JOURNAL OF ALLOYS AND COMPOUNDS LA English DT Article DE crystal structure; ruthenium stannide; intermetallic; neutron diffraction ID SUPERCONDUCTORS AB Millimeter-sized single crystals of the title compound have been grown from a Sn-rich melt and neutron diffraction data recorded at room temperature and 20 K have been used to confirm and refine the crystal structure. The Ir3Ge7 structure-type, cubic Im (3) over bar m can be viewed as a framework of alternating corner linked Ru6Sn8 capped-octahedral clusters and Ru3Sn4 flattened-octahedral clusters, such that the latter form their own three-dimensional sublattice. The Ru-Sn distances determined for Ru3Sn7 fall in the middle of the observed range tabulated from the handful of known Ru-Sn distances in intermetallics. The resistivity of Ru3Sn7 is metallic, with a value of 72 mu Omega cm at 300 K and 0.5 mu Omega cm at 5 K. The magnetic susceptibility is diamagnetic at room temperature, but becomes paramagnetic as the temperature is lowered. We interpret the susceptibility as being due to a diamagnetic 'core' contribution and a paramagnetic contribution arising from the Ru d orbitals. (C) 1998 Elsevier Science S.A. All rights reserved. C1 Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Chakoumakos, BC (reprint author), Oak Ridge Natl Lab, Div Solid State, POB 2008, Oak Ridge, TN 37831 USA. RI Mandrus, David/H-3090-2014; Chakoumakos, Bryan/A-5601-2016 OI Chakoumakos, Bryan/0000-0002-7870-6543 NR 12 TC 13 Z9 13 U1 0 U2 8 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0925-8388 J9 J ALLOY COMPD JI J. Alloy. Compd. PD DEC 18 PY 1998 VL 281 IS 2 BP 157 EP 159 DI 10.1016/S0925-8388(98)00790-7 PG 3 WC Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering GA 153MY UT WOS:000077837900014 ER PT J AU Yun, T Smith, MS Guiochon, G AF Yun, T Smith, MS Guiochon, G TI Theoretical analysis of the behavior of a centrally injected band in a homogeneous chromatographic column SO JOURNAL OF CHROMATOGRAPHY A LA English DT Article; Proceedings Paper CT 22nd International Symposium on High Performance Liquid Phase Separations and Related Techniques CY MAY 02-08, 1998 CL ST LOUIS, MISSOURI DE equilibrium-dispersive model; band profiles; preparative chromatography; injection parameters ID LIQUID-CHROMATOGRAPHY; DISPERSION COEFFICIENTS; RADIAL-DISTRIBUTION; AXIAL-DISPERSION; FLOW VELOCITY; CONSOLIDATION; TRANSVERSE; EFFICIENCY; PACKING; BEDS AB A new implementation of the equilibrium-dispersive model permits the study of problems requiring two-space dimensions for their modeling, such as a nonhomogeneous column with a cylindrical symmetry, a nonplanar injection with a cylindrical symmetry, or a cylindrical central injection. The migration and broadening of a cylindrical band coaxial with the column but narrower, moving along a homogeneous column is studied. The axial and radial profiles of the band inside the column and the elution profiles are calculated. These profiles depend on both the radial and the axial dispersion coefficients. The radial dispersion coefficient decreases with increasing mobile phase velocity and is usually low, much lower than the axial dispersion coefficient. Thus, the material in a relatively wide central injection made on a wide bore column may never have a chance to get close to the column wall. The clearance required at injection is estimated. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Guiochon, G (reprint author), Univ Tennessee, Dept Chem, 575 Buehler Hall, Knoxville, TN 37996 USA. NR 28 TC 8 Z9 8 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0021-9673 J9 J CHROMATOGR A JI J. Chromatogr. A PD DEC 18 PY 1998 VL 828 IS 1-2 BP 19 EP 35 DI 10.1016/S0021-9673(98)00663-3 PG 17 WC Biochemical Research Methods; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA 152ZP UT WOS:000077808500003 ER PT J AU Wang, S Porter, MD AF Wang, S Porter, MD TI Enantiomeric separations of benzodiazepines by electrochemically modulated liquid chromatography SO JOURNAL OF CHROMATOGRAPHY A LA English DT Article; Proceedings Paper CT 22nd International Symposium on High Performance Liquid Phase Separations and Related Techniques CY MAY 02-08, 1998 CL ST LOUIS, MISSOURI DE enantiomer separation; electrochemically modulated liquid chromatography; porous graphite carbon; liquid chromatography; electrochemically modulated; stationary phases, LC; benzodiazepines; oxazepam; lorazepam; temazepam ID CYCLODEXTRIN INCLUSION COMPLEXES; CONDUCTIVE STATIONARY-PHASE; BETA-CYCLODEXTRIN; EXCHANGE CHROMATOGRAPHY; ALPHA-CYCLODEXTRIN; GAMMA-CYCLODEXTRIN; BONDED PHASES; RESOLUTION; COLUMN; ELECTROCHROMATOGRAPHY AB Electrochemically modulated liquid chromatography (EMLC) has been applied to the enantiomeric separation of a group of benzodiazepines (i.e., oxazepam, lorazepam and temazepam) using a porous graphitic carbon (PGC) stationary phase and beta-cyclodextrin (beta-CD) as a chiral mobile phase additive. The basis of the separation derives from the reversible electrosorption of the additive onto PGC, resulting in a new approach for manipulating the chirality and selectivity of the stationary phase. Changes in the voltage applied (E-appl) to the stationary phase were found to alter the retention and the enantioselectivity of the separation, both of which reflect the dependence of the electrosorption of the additive on E-appl. By exploiting these dependencies, mixtures of each of the three racemates could be resolved to differing extents while using the same isocratic elution condition. A general description of the retention process and the role of the apparent enantiomerization of oxazepam and lorazepam are briefly discussed. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Iowa State Univ, US DOE, Ames Lab, Microanalyt Instrumentat Ctr, Ames, IA 50011 USA. Iowa State Univ, Dept Chem, Ames, IA 50011 USA. RP Porter, MD (reprint author), Iowa State Univ, US DOE, Ames Lab, Microanalyt Instrumentat Ctr, Ames, IA 50011 USA. EM mporter@porter1.ameslab.gov NR 54 TC 20 Z9 21 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0021-9673 J9 J CHROMATOGR A JI J. Chromatogr. A PD DEC 18 PY 1998 VL 828 IS 1-2 BP 157 EP 166 DI 10.1016/S0021-9673(98)00701-8 PG 10 WC Biochemical Research Methods; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA 152ZP UT WOS:000077808500017 ER PT J AU Tsuruta, H Reddy, VS Wikoff, WR Johnson, JE AF Tsuruta, H Reddy, VS Wikoff, WR Johnson, JE TI Imaging RNA and dynamic protein segments with low-resolution virus crystallography: Experimental design, data processing and implications of electron density maps SO JOURNAL OF MOLECULAR BIOLOGY LA English DT Article DE virus crystallography; virus structure; bacteriophage structure; protein crystallography; small angle scattering ID MACROMOLECULAR PHASE PROBLEM; ICOSAHEDRAL ANIMAL VIRUS; RAY SOLUTION SCATTERING; REAL-SPACE ENVELOPES; VERY-LOW RESOLUTION; FLOCK HOUSE VIRUS; 22.5-A RESOLUTION; MOSAIC-VIRUS; CRYSTALLIZATION; SYSTEM AB Single crystal diffraction data were collected from virus crystals in the resolution range of 270 to 14 Angstrom using a synchrotron X-ray source and a small-angle scattering instrument adapted for single crystal measurements. Reflections were measured from single crystals of the capsid of the double-stranded DNA bacteriophage HK97 and synthetic Flock House virus-like particles (sFHV). The quality of the low-resolution measurements was confirmed by excellent scaling statistics for both data sets. The sFHV amplitudes between 270 and 90 Angstrom resolution were closely similar to independently measured solution scattering data, and to data calculated from the Fourier transform of a uniform density sphere of 315 Angstrom diameter. A rotation function computed with the sFHV data between 70 and 20 Angstrom resolution was readily interpretable. A uniform density sphere model was used to compute phases for measured amplitudes between 270 and 68 Angstrom resolution. The calculated phases were refined and extended to 14 Angstrom resolution with real space averaging employing an external mask share defined by the high-resolution structure. The resulting electron density map displayed regions interpretable as loosely ordered RNA that connected ordered RNA segments seen in a published 3.0 Angstrom resolution map. The published high-resolution electron density map lacked data inside 15 Angstrom resolution and the interior of the particle in that map appeared hollow. Difference electron density maps corresponding to bulk RNA were computed by subtracting the contribution of the protein shell, based on the available high-resolution atomic model, from either the cryo-electron microscopy density or the low-resolution X-ray density. Features of the RNA were closely similar in the cryo-electron microscopy and X-Pay maps, demonstrating the consistency of the two imaging methods. Electron density maps computed at 14 and 6 Angstrom resolution with the X-my amplitudes showed that RNA contributed little to the scattering beyond 14 Angstrom resolution. (C) 1998 Academic Press. C1 Scripps Res Inst, Dept Mol Biol, La Jolla, CA 92037 USA. Stanford Univ, SSRL, SLAC, Stanford, CA 94309 USA. Purdue Univ, Dept Biol Sci, W Lafayette, IN 47907 USA. RP Johnson, JE (reprint author), Scripps Res Inst, Dept Mol Biol, MB-31,10550 N Torrey Pines Rd, La Jolla, CA 92037 USA. FU NIAID NIH HHS [AI40101]; NIGMS NIH HHS [GM54076] NR 42 TC 28 Z9 28 U1 0 U2 3 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0022-2836 J9 J MOL BIOL JI J. Mol. Biol. PD DEC 18 PY 1998 VL 284 IS 5 BP 1439 EP 1452 DI 10.1006/jmbi.1998.2231 PG 14 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 150EW UT WOS:000077651400019 PM 9878362 ER PT J AU Misra, A Petrovic, JJ Mitchell, TE AF Misra, A Petrovic, JJ Mitchell, TE TI Microstructures and mechanical properties of a Mo3Si-Mo5Si3 composite SO SCRIPTA MATERIALIA LA English DT Article ID MOSI2-MO5SI3 EUTECTICS; BEHAVIOR; MO5SI3; CREEP; BORON C1 Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. RP Misra, A (reprint author), Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, MS K765, Los Alamos, NM 87545 USA. RI Misra, Amit/H-1087-2012 NR 19 TC 9 Z9 11 U1 0 U2 4 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1359-6462 J9 SCRIPTA MATER JI Scr. Mater. PD DEC 18 PY 1998 VL 40 IS 2 BP 191 EP 196 DI 10.1016/S1359-6462(98)00406-0 PG 6 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 162RJ UT WOS:000078360300010 ER PT J AU Hou, PY Prussner, K Fairbrother, DH Roberts, JG Alexander, KB AF Hou, PY Prussner, K Fairbrother, DH Roberts, JG Alexander, KB TI Sulfur segregation to deposited Al2O3 film/alloy interface at 1000 degrees C SO SCRIPTA MATERIALIA LA English DT Article ID SURFACE; STEELS C1 Lawrence Berkeley Natl Lab, Div Mat Sci, Berkeley, CA 94720 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Hou, PY (reprint author), Lawrence Berkeley Natl Lab, Div Mat Sci, Berkeley, CA 94720 USA. RI Pruessner, Karin/A-4949-2009 NR 16 TC 2 Z9 2 U1 1 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1359-6462 J9 SCRIPTA MATER JI Scr. Mater. PD DEC 18 PY 1998 VL 40 IS 2 BP 241 EP 247 DI 10.1016/S1359-6462(98)00418-7 PG 7 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 162RJ UT WOS:000078360300018 ER PT J AU Kalemos, A Mavridis, A Xantheas, SS AF Kalemos, A Mavridis, A Xantheas, SS TI Theoretical investigation of the ground X-3 Sigma(-) state of nitrogen bromide SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID CONFIGURATION-INTERACTION CALCULATIONS; MOLECULAR WAVE-FUNCTIONS; BENCHMARK CALCULATIONS; BASIS-SETS; DIATOMIC HYDRIDES; 1ST-ROW; ENERGY; ATOMS; PCL AB The spectroscopic constants and the dissociation energy of the ground X(3)Sigma(-) State of NBr have been computed using correlated wave functions and correlation-consistent orbital basis sets up to quintuple zeta quality. Our best estimates for the equilibrium separation (r(e)) is 1.780 Angstrom and for the dissociation energy (D-e) 49.5 kcal/ mel, suggesting that previous estimates obtained from indirect experimental measurements are in error by as much as 15 kcal/mol. The spectroscopic constants computed at the RCCSD(T)/aug-cc-pV5Z level of theory are omega(e) = 694.5 cm(-1), omega(e)chi(e) = 4.14 cm(-1) and alpha(e) = 0.0039 cm(-1). The linear variation of D-e for the NX species (X = F, Cl, Br) supports a prediction of about 35 kcal/mol for the dissociation energy of NI. C1 Natl & Kapodistrian Univ Athens, Dept Chem, Chem Phys Lab, Zografos 15710, Greece. Pacific NW Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Mavridis, A (reprint author), Natl & Kapodistrian Univ Athens, Dept Chem, Chem Phys Lab, POB 64004, Zografos 15710, Greece. RI Xantheas, Sotiris/L-1239-2015; OI Kalemos, Apostolos/0000-0002-1022-0029 NR 31 TC 4 Z9 4 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5639 J9 J PHYS CHEM A JI J. Phys. Chem. A PD DEC 17 PY 1998 VL 102 IS 51 BP 10536 EP 10539 DI 10.1021/jp982875u PG 4 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 151GW UT WOS:000077713200012 ER PT J AU Hummer, G Garde, S Garcia, AE Paulaitis, ME Pratt, LR AF Hummer, G Garde, S Garcia, AE Paulaitis, ME Pratt, LR TI Hydrophobic effects on a molecular scale SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Review ID TEMPERATURE-DEPENDENCE; COMPUTER-SIMULATION; FREE-ENERGIES; HIGH-PRESSURE; MONTE-CARLO; PROTEIN-STRUCTURE; WATER-STRUCTURE; SURFACE-AREA; MEAN-FORCE; HYDRATION AB A theoretical approach is developed to quantify hydrophobic hydration and interactions on a molecular scale, with the goal of insight into the molecular origins of hydrophobic effects. The model is based on the fundamental relation between the probability for cavity formation in bulk water resulting from molecular-scale density fluctuations and the hydration free energy of the simplest hydrophobic solutes, hard particles. This probability is estimated using an information theory (IT) approach, incorporating experimentally available properties of bulk water: the density and radial distribution function. The IT approach reproduces the simplest hydrophobic effects: hydration of spherical nonpolar solutes, the potential of mean force (PMF) between methane molecules, and solvent contributions to the torsional equilibrium of butane. Applications of this approach to study temperature and pressure effects provide new insights into the thermodynamics and kinetics of protein folding. The IT model relates the hydrophobic-entropy convergence observed in protein unfolding experiments to the macroscopic isothermal compressibility of water. A novel explanation for pressure denaturation of proteins follows from an analysis of the pressure stability of hydrophobic aggregates, suggesting that water penetrates the hydrophobic core of proteins at high pressures. This resolves a long-standing puzzle, whether pressure denaturation contradicts the hydrophobic-core model of protein stability. Finally, issues of "dewetting" of molecularly large nonpolar solutes are discussed in the context of a recently developed perturbation theory approach. C1 Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Johns Hopkins Univ, Dept Chem Engn, Baltimore, MD 21218 USA. RP Hummer, G (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RI Garde, Shekhar/C-3060-2008; Pratt, Lawrence/H-7955-2012; Hummer, Gerhard/A-2546-2013 OI Pratt, Lawrence/0000-0003-2351-7451; Hummer, Gerhard/0000-0001-7768-746X NR 104 TC 281 Z9 281 U1 7 U2 92 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5647 J9 J PHYS CHEM B JI J. Phys. Chem. B PD DEC 17 PY 1998 VL 102 IS 51 BP 10469 EP 10482 DI 10.1021/jp982873+ PG 14 WC Chemistry, Physical SC Chemistry GA 151GX UT WOS:000077713300001 ER PT J AU Carbeck, JD Severs, JC Gao, JM Wu, QY Smith, RD Whitesides, GM AF Carbeck, JD Severs, JC Gao, JM Wu, QY Smith, RD Whitesides, GM TI Correlation between the charge of proteins in solution and in the gas phase investigated by protein charge ladders, capillary electrophoresis, and electrospray ionization mass spectrometry SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID DIELECTRIC POLARIZABILITY; POSITIVE-ION; SPECTRA; PRINCIPLES; EQUILIBRIA; CHEMISTRY AB Charge ladders of bovine carbonic anhydrase II, hen egg-white lysozyme, and bovine pancreatic trypsin inhibitor, prepared by partial acetylation of primary amino groups on the surface of the protein, have been analyzed by capillary electrophoresis (CE) and on-line electrospray ionization mass spectrometry (ESIMS) using solution conditions that maintain the native structure of the protein. CE was used to separate the proteins that constitute the charge ladder into individual "rungs"-protein derivatives that have the same number of acetylated amino groups and approximately the same net charge in solution. ESI was used to produce ions in the gas phase of the proteins that constitute each rung of the charge ladder; the mass spectra of these ions were obtained and analyzed. The distributions in charge states observed in the gas phase for the groups of proteins comprising each rung of the charge ladders were narrow, consistent with the retention of a compact structure of the proteins in the gas phase, and substantially independent of the number of acetylated amino groups. The ions observed in the gas phase had surface charge densities in a relatively narrow range of similar to 0.9-1.5 units of charge per 10(3) Angstrom(2) of surface area las estimated from crystallographic structures). These results demonstrate that the distribution of charge states for proteins produced in the gas phase by ESI do not necessarily reflect the net charge of the protein in solution or the number of amino groups on the protein. C1 Pacific NW Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. Harvard Univ, Dept Chem & Chem Biol, Cambridge, MA 02138 USA. RP Smith, RD (reprint author), Pacific NW Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. EM rd_smith@pnl.gov; gwhitesides@gmwgroup.harvard.edu RI Smith, Richard/J-3664-2012 OI Smith, Richard/0000-0002-2381-2349 NR 27 TC 33 Z9 33 U1 0 U2 12 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5647 J9 J PHYS CHEM B JI J. Phys. Chem. B PD DEC 17 PY 1998 VL 102 IS 51 BP 10596 EP 10601 DI 10.1021/jp980768u PG 6 WC Chemistry, Physical SC Chemistry GA 151GX UT WOS:000077713300015 ER PT J AU Hung, LW Wang, IXY Nikaido, K Liu, PQ Ames, GFL Kim, SH AF Hung, LW Wang, IXY Nikaido, K Liu, PQ Ames, GFL Kim, SH TI Crystal structure of the ATP-binding subunit of an ABC transporter SO NATURE LA English DT Article ID PERIPLASMIC HISTIDINE PERMEASE; ELECTRON-DENSITY MAPS; ESCHERICHIA-COLI; CYSTIC-FIBROSIS; TRAFFIC ATPASE; PROTEIN; IDENTIFICATION; RESOLUTION; HYDROLYSIS; HUMANS AB ABC transporters (also known as traffic ATPases) form a large family of proteins responsible for the translocation of a variety of compounds across membranes of both prokaryotes and eukaryotes'. The recently completed Escherichia coli genome sequence revealed that the largest family of paralogous E. coli proteins is composed of ABC transporters(2), Many eukaryotic proteins of medical significance belong to this family, such as the cystic fibrosis transmembrane conductance regulator (CFTR), the P-glycoprotein (or multidrug-resistance protein) and the heterodimeric transporter associated with antigen processing (Tap1-Tap2). Here we report the crystal structure at 1.5 Angstrom resolution of HisP, the ATP-binding subunit of the histidine permease, which is an ABC transporter from Salmonella typhimurium, We correlate the details of this structure with the biochemical, genetic and biophysical properties of the wild-type and several mutant HisP proteins. The structure provides a basis for understanding properties of ABC transporters and of defective CFTR proteins. C1 Univ Calif Berkeley, EO Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Mol & Cell Biol, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. RP Kim, SH (reprint author), Univ Calif Berkeley, EO Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. EM shkim@lbl.gov NR 30 TC 549 Z9 554 U1 4 U2 26 PU NATURE PUBLISHING GROUP PI LONDON PA MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 EI 1476-4687 J9 NATURE JI Nature PD DEC 17 PY 1998 VL 396 IS 6712 BP 703 EP 707 PG 5 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 150YT UT WOS:000077694200060 PM 9872322 ER PT J AU Pfutzner, M Armbruster, P Baumann, T Benlliure, J Bernas, M Catford, WN Cortina-Gil, D Daugas, JM Geissel, H Gorska, M Grawe, H Grzywacz, R Hellstrom, M Iwasa, N Janas, Z Junghans, AR Karny, M Leenhardt, S Lewitowicz, M Mueller, AC de Oliviera, F Regan, PH Rejmund, M Rykaczewski, K Summerer, K AF Pfutzner, M Armbruster, P Baumann, T Benlliure, J Bernas, M Catford, WN Cortina-Gil, D Daugas, JM Geissel, H Gorska, M Grawe, H Grzywacz, R Hellstrom, M Iwasa, N Janas, Z Junghans, AR Karny, M Leenhardt, S Lewitowicz, M Mueller, AC de Oliviera, F Regan, PH Rejmund, M Rykaczewski, K Summerer, K TI New isotopes and isomers produced by the fragmentation of U-238 at 1000 MeV/nucleon SO PHYSICS LETTERS B LA English DT Article ID MU-S-ISOMERS; NUCLEAR COLLISIONS; IDENTIFICATION; BEAM AB Seven previously unobserved neutron-rich isotopes (Hg-209, Hg-210, Tl-211,Tl- 212, Bi-218, Po-219 and Po-220) have been identified among the fragmentation products of a 1000 MeV/nucleon U-238 beam incident on a beryllium target. The gamma-ray decays of 9 known and 4 new mu s-isomers in nuclei around Pb-208 were also observed. Production cross sections and probabilities for populating isomeric states in the fragmentation reaction were determined and compared with a simple model based on the statistical abrasion-ablation approach. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Univ Warsaw, IEP, PL-00861 Warsaw, Poland. GSI Darmstadt, D-64220 Darmstadt, Germany. Inst Phys Nucl, F-91406 Orsay, France. Univ Surrey, Dept Phys, Guildford GU2 5XH, Surrey, England. GANIL, F-14021 Caen, France. Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. RP Pfutzner, M (reprint author), Univ Warsaw, IEP, Hoza 69, PL-00861 Warsaw, Poland. RI Junghans, Arnd/D-4596-2012; Cortina-Gil, Dolores/H-9626-2015; Benlliure, Jose/K-8407-2014 OI Cortina-Gil, Dolores/0000-0001-7672-9912; Benlliure, Jose/0000-0002-5114-1298 NR 31 TC 91 Z9 91 U1 0 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 J9 PHYS LETT B JI Phys. Lett. B PD DEC 17 PY 1998 VL 444 IS 1-2 BP 32 EP 37 DI 10.1016/S0370-2693(98)01332-X PG 6 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 154KH UT WOS:000077887700006 ER PT J AU Agashe, K AF Agashe, K TI GUT and SUSY breaking by the same field SO PHYSICS LETTERS B LA English DT Article AB We present a model in which the same modulus field breaks both SUSY and a simple GUT gauge group down to the SM gauge group. The modulus is stabilized by the inverted hierarchy mechanism in a perturbative region so that the model is calculable. This is the first example of this kind in the literature. All mass scales (other than the Planck scale) are generated dynamically. In one of the models doublet-triplet splitting is achieved naturally by the sliding singlet mechanism while another model requires fine tuning. The gauge mediation contribution to the right handed slepton (mass)(2) is negative. But, for the modulus vacuum expectation value close to the GUT scale, the supergravity contribution to the slepton (mass)(2) is comparable to the gauge mediation contribution and thus a realistic spectrum can be attained. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Theoret Phys Grp, Berkeley, CA 94720 USA. Univ Oregon, Inst Theoret Sci, Eugene, OR 97403 USA. RP Agashe, K (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Theoret Phys Grp, Berkeley, CA 94720 USA. NR 9 TC 12 Z9 12 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 J9 PHYS LETT B JI Phys. Lett. B PD DEC 17 PY 1998 VL 444 IS 1-2 BP 61 EP 67 DI 10.1016/S0370-2693(98)01310-0 PG 7 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 154KH UT WOS:000077887700010 ER PT J AU Hillman, AR Brown, MJ Martin, SJ AF Hillman, AR Brown, MJ Martin, SJ TI Resonance effects in electroactive poly(3-hexylthiophene) films SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID QUARTZ-CRYSTAL RESONATOR; THIN-FILMS C1 Univ Leicester, Dept Chem, Leicester LE1 7RH, Leics, England. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Hillman, AR (reprint author), Univ Leicester, Dept Chem, Leicester LE1 7RH, Leics, England. NR 20 TC 12 Z9 12 U1 0 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0002-7863 J9 J AM CHEM SOC JI J. Am. Chem. Soc. PD DEC 16 PY 1998 VL 120 IS 49 BP 12968 EP 12969 DI 10.1021/ja9829766 PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA 149MW UT WOS:000077610100035 ER PT J AU Luo, J Wishart, JF Isied, SS AF Luo, J Wishart, JF Isied, SS TI Site-dependent stereoselective binding of ruthenium aquobipyridine complexes to histidine side chains in horse heart cytochrome c SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID INTRAMOLECULAR ELECTRON-TRANSFER; CHIRAL DISCRIMINATION; MINOR-GROOVE; DNA; CHEMISTRY; OXIDATION C1 Rutgers State Univ, Dept Chem, Piscataway, NJ 08855 USA. Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. RP Isied, SS (reprint author), Rutgers State Univ, Dept Chem, Piscataway, NJ 08855 USA. RI Wishart, James/L-6303-2013 OI Wishart, James/0000-0002-0488-7636 NR 29 TC 6 Z9 6 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0002-7863 J9 J AM CHEM SOC JI J. Am. Chem. Soc. PD DEC 16 PY 1998 VL 120 IS 49 BP 12970 EP 12971 DI 10.1021/ja9829261 PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA 149MW UT WOS:000077610100036 ER PT J AU Jensen, TR Norby, P Christensen, AN Hanson, JC AF Jensen, TR Norby, P Christensen, AN Hanson, JC TI Hydrothermal synthesis, crystal structure refinement and thermal transformation of LiZnAsO4.H2O SO MICROPOROUS AND MESOPOROUS MATERIALS LA English DT Article DE ABW; crystal structure; in situ synchrotron radiation powder diffraction; lithium zinc arsenate hydrate; synthesis; thermal transformation ID LITHIUM ZINC PHOSPHATE; SYNCHROTRON POWDER DIFFRACTION; ZEOLITE LI-A(BW); TEMPERATURE SYNTHESIS; ABW-TYPE; ARSENATE; FRAMEWORK; LIZNPO4; PHASES AB The system LiOH-Zn(NO3)(2)-H3AsO4-H2O was investigated using hydrothermal synthesis in the temperature range 20-240 degrees C. In addition to alpha-LiZnAsO4, ZnHAsO4. H2O and Zn-9(AsO4)(6). 4H(2)O a microporous lithium zinc orthoarsenate LiZnAsO4. H2O can be prepared in neutral to slightly acidic solution at low temperature. The crystal structure of LiZnAsO4. H2O can be viewed as an ABW type framework of AsO4 and ZnO4 tetrahedra forming 8-ring channels in the c direction where the extra framework lithium cations and water molecules are placed. The Li cations are forming tetrahedra by coordination to three framework oxygens and the water oxygen atom. Rietveld refinement was performed on powder diffraction data using synchrotron X-rays, lambda=1.3808(1)Angstrom, R-p=0.0458, wR(p)=0.063. Crystal data of the orthorhombic LiZnAsO4. H2O: a=10.8472(9), b=8.2903(5) and c=5.1575(4) Angstrom, V=463.80(6) Angstrom(3), Pna2(1) (No.33), Z=4, M=229.255 g mol(-1), D-c=3.328 g cm(-3). The thermal expansion of LiZnAsO4. H2O and dehydration to form alpha-LiZnAsO4 by dry hearing was investigated using in situ synchrotron radiation powder diffraction, [lambda=1.0989(1) Angstrom] thermogravimetry and differential scanning calorimetry giving an endothermic enthalpy change of Delta H=36(7) kJ mol(-1), peak value at 218(2)degrees C. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Odense Univ, Dept Chem, DK-5230 Odense M, Denmark. Aarhus Univ, Dept Chem, DK-8000 Aarhus, Denmark. Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. RP Jensen, TR (reprint author), Odense Univ, Dept Chem, Campusvej 55, DK-5230 Odense M, Denmark. RI Hanson, jonathan/E-3517-2010; Norby, Poul/B-9047-2014; OI Norby, Poul/0000-0002-2590-7050; Jensen, Torben Rene/0000-0002-4278-3221 NR 45 TC 12 Z9 12 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 1387-1811 J9 MICROPOR MESOPOR MAT JI Microporous Mesoporous Mat. PD DEC 16 PY 1998 VL 26 IS 1-3 BP 77 EP 87 DI 10.1016/S1387-1811(98)00217-0 PG 11 WC Chemistry, Applied; Chemistry, Physical; Nanoscience & Nanotechnology; Materials Science, Multidisciplinary SC Chemistry; Science & Technology - Other Topics; Materials Science GA 150AE UT WOS:000077639100009 ER PT J AU Mendoza, CI Barrera, RG Fuchs, R AF Mendoza, CI Barrera, RG Fuchs, R TI Local-field effects at crystalline surfaces: Electron energy loss from ordered arrays of spheres SO PHYSICA STATUS SOLIDI A-APPLIED RESEARCH LA English DT Article; Proceedings Paper CT 5th Epioptics Workshop CY JUN 17-22, 1998 CL ERICE, ITALY SP Ettore Majorana Fdn, Ctr Sci Culture ID OPTICAL REFLECTANCE; SINGLE-CRYSTALS; ANISOTROPY AB Local-field effects at crystalline surfaces are analyzed on a classical system consistent of ordered arrays of polarizable spheres. A theory for the energy loss of fast electrons traveling parallel to these arrays is presented. A spectral representation of the surface response function is used to calculate this energy loss. The poles and weights in this representation are determined through the eigenvalues and eigenvectors of an interaction matrix which takes into account the quasi-static electromagnetic fields to an arbitrary multipolar order. We apply the theory to calculate the energy-loss spectra for cubic arrays of aluminum spheres embedded in vacuum and compare the results with those obtained using a dielectric continuum model. C1 Univ Nacl Autonoma Mexico, Inst Fis, Mexico City 01000, DF, Mexico. Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. RP Mendoza, CI (reprint author), Univ Nacl Autonoma Mexico, Inst Fis, Apartado Postal 20-364, Mexico City 01000, DF, Mexico. NR 11 TC 1 Z9 1 U1 0 U2 0 PU WILEY-V C H VERLAG GMBH PI BERLIN PA MUHLENSTRASSE 33-34, D-13187 BERLIN, GERMANY SN 0031-8965 J9 PHYS STATUS SOLIDI A JI Phys. Status Solidi A-Appl. Res. PD DEC 16 PY 1998 VL 170 IS 2 BP 349 EP 356 DI 10.1002/(SICI)1521-396X(199812)170:2<349::AID-PSSA349>3.0.CO;2-B PG 8 WC Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA 154AP UT WOS:000077866100025 ER PT J AU Li, RC AF Li, RC TI Relative perturbation theory: II. Eigenspace and singular subspace variations SO SIAM JOURNAL ON MATRIX ANALYSIS AND APPLICATIONS LA English DT Article DE multiplicative perturbation; relative perturbation theory; relative gap; eigenvector; singular vector; structured Sylvester equation; graded matrix ID ACCURATE; MATRICES; VALUES; BOUNDS AB The classical perturbation theory for Hermitian matrix eigenvalue and singular value problems provides bounds on invariant subspace variations that are proportional to the reciprocals of absolute gaps between subsets of spectra or subsets of singular values. these bounds may be bad news for invariant subspaces corresponding to clustered eigenvalues or clustered singular values of much smaller magnitudes than the norms of matrices under considerations. In this paper, we consider how eigenspaces of a Hermitian matrix A change when its perturbed to (A) over tilde = D* AD and how singular spaces of a (nonsquare) matrix B change when it is perturbed to (B) over tilde = D(1)* BD(2), where D, D(1) and D(2) are nonsingular. It is proved that under these kinds of perturbations, the changes of invariant subspaces are proportional to the reciprocals of relative gaps between subsets of spectra or subsets of singular values. The classical Davis-Kahan sin theta theorems and Wedin sin theta theorems are extended. C1 Oak Ridge Natl Lab, Math Sci Sect, Oak Ridge, TN 37831 USA. RP Li, RC (reprint author), Univ Kentucky, Dept Math, Lexington, KY 40506 USA. EM rcli@ms.uky.edu NR 18 TC 55 Z9 57 U1 0 U2 1 PU SIAM PUBLICATIONS PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 USA SN 0895-4798 J9 SIAM J MATRIX ANAL A JI SIAM J. Matrix Anal. Appl. PD DEC 16 PY 1998 VL 20 IS 2 BP 471 EP 492 DI 10.1137/S0895479896298506 PG 22 WC Mathematics, Applied SC Mathematics GA 148MD UT WOS:000077508400001 ER PT J AU Rabinovich, D Schimek, GL Pennington, WT Nielsen, JB Abney, KD AF Rabinovich, D Schimek, GL Pennington, WT Nielsen, JB Abney, KD TI Octaaquabromouranium(IV) tribromide monohydrate, [UBr(H2O)(8)]Br-3 center dot H2O SO ACTA CRYSTALLOGRAPHICA SECTION C-CRYSTAL STRUCTURE COMMUNICATIONS LA English DT Article ID CROWN ETHER COMPLEXES; CRYSTAL-STRUCTURE AB The cationic uranium complex, [U(H2O)(8)Br](3+), presents a tricapped trigonal prismatic structure in the solid state, with U-O distances (at T = 150 K) in the range 2.379 (8)-2.455 (8) Angstrom and a U-Br bond length of 2.885 (2) Angstrom. in addition to an extended network of intermolecular hydrogen-bonding interactions. The title compound is the first octaaqua complex to be structurally characterized for an actinide element. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Clemson Univ, Dept Chem, Clemson, SC 29634 USA. RP Rabinovich, D (reprint author), Univ Calif Los Alamos Natl Lab, CST-11,Mail Stop J514, Los Alamos, NM 87545 USA. NR 20 TC 1 Z9 1 U1 0 U2 0 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0108-2701 J9 ACTA CRYSTALLOGR C JI Acta Crystallogr. Sect. C-Cryst. Struct. Commun. PD DEC 15 PY 1998 VL 54 BP 1740 EP 1742 DI 10.1107/S0108270198008233 PN 12 PG 3 WC Chemistry, Multidisciplinary; Crystallography SC Chemistry; Crystallography GA 161WY UT WOS:000078313700006 ER PT J AU Waters, LC Jacobson, SC Kroutchinina, N Khandurina, J Foote, RS Ramsey, JM AF Waters, LC Jacobson, SC Kroutchinina, N Khandurina, J Foote, RS Ramsey, JM TI Multiple sample PCR amplification and electrophoretic analysis on a microchip SO ANALYTICAL CHEMISTRY LA English DT Article ID CAPILLARY ELECTROPHORESIS; POSTCOLUMN REACTOR; DNA; PERFORMANCE; DEVICES AB Polymerase chain reactions (PCRs) were carried out on as many as four DNA samples at a time on a microchip device. The PCR products were then analyzed, either individually or together on the same device, by microchip gel electrophoresis. A standard PCR protocol was used to amplify 199- and 500-base pair (bp) regions of bacteriophage lambda DNA and 346- and 410-bp regions of E. coli genomic and plasmid DNAs, respectively. Thermal lysis of the bacteria was integrated into the PCR cycle. A product sizing medium, poly(dimethylacrylamide), and an intercalating dye for fluorescence detection were used in the electrophoretic analysis of the products. PCR product sizes were determined by coelectrophoresis with marker DNA. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Ramsey, JM (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. NR 18 TC 209 Z9 212 U1 1 U2 17 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0003-2700 J9 ANAL CHEM JI Anal. Chem. PD DEC 15 PY 1998 VL 70 IS 24 BP 5172 EP 5176 DI 10.1021/ac980447e PG 5 WC Chemistry, Analytical SC Chemistry GA 148TY UT WOS:000077550100010 PM 9868915 ER PT J AU Wong, SS Takano, H Porter, MD AF Wong, SS Takano, H Porter, MD TI Mapping orientation differences of terminal functional groups by friction force microscopy SO ANALYTICAL CHEMISTRY LA English DT Article ID SELF-ASSEMBLED MONOLAYERS; CHAIN-LENGTH DEPENDENCE; N-ALKANOIC ACIDS; ALKANETHIOLATE MONOLAYERS; SILVER SURFACES; THIN-FILMS; GOLD; ADHESION; SCALE; MICA AB The ability to map differences in the spatial orientation of terminal chemical groups is of major significance to areas as diverse as biological recognition and boundary lubrication. This capability is demonstrated herein using a scanning force microscope to detect differences in the friction between a probe tip and organic monolayers with different terminal group orientations. As a starting point, the basis for the discrimination of the orientation differences in terminal groups is developed through considerations of surface free energy. The viability of the concept is then confirmed by the friction imaging of samples patterned with alternating domains of organic monolayers having different terminal group orientations. Opportunities presented by this new capability are briefly noted. C1 US DOE, Ames Lab, Microanalyt Instrumentat Ctr, Ames, IA 50011 USA. Iowa State Univ, Dept Chem, Ames, IA 50011 USA. RP Porter, MD (reprint author), US DOE, Ames Lab, Microanalyt Instrumentat Ctr, Ames, IA 50011 USA. EM mporter@porter1.ameslab.gov NR 43 TC 67 Z9 67 U1 2 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0003-2700 J9 ANAL CHEM JI Anal. Chem. PD DEC 15 PY 1998 VL 70 IS 24 BP 5209 EP 5212 DI 10.1021/ac9807870 PG 4 WC Chemistry, Analytical SC Chemistry GA 148TY UT WOS:000077550100015 ER PT J AU Van Siclen, CD AF Van Siclen, CD TI Information measure of location precision SO APPLIED MATHEMATICS AND COMPUTATION LA English DT Article DE information theory; information entropy; information content; location precision; object location AB The optimal grid size for specifying object location in one and two dimensions is found by maximizing the information content (entropy) of the system in which the objects reside. The information content increases logarithmically as the decreasing grid size approaches the object size, reflecting the increasing precision of object location, but thereafter the increase is not monotonic. This implies, for example, that the fidelity of a digitized image is dependent on pixel size in a nontrivial way. (C) 1998 Elsevier Science Inc. All rights reserved. C1 Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. RP Van Siclen, CD (reprint author), Idaho Natl Engn & Environm Lab, POB 1625, Idaho Falls, ID 83415 USA. NR 2 TC 0 Z9 0 U1 1 U2 1 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0096-3003 J9 APPL MATH COMPUT JI Appl. Math. Comput. PD DEC 15 PY 1998 VL 97 IS 2-3 BP 287 EP 293 DI 10.1016/S0096-3003(97)10142-4 PG 7 WC Mathematics, Applied SC Mathematics GA 116JF UT WOS:000075720600013 ER PT J AU Staudigel, H Yayanos, A Chastain, R Davies, G Verdurmen, EAT Schiffman, P Bourcier, R De Baar, H AF Staudigel, H Yayanos, A Chastain, R Davies, G Verdurmen, EAT Schiffman, P Bourcier, R De Baar, H TI Biologically mediated dissolution of volcanic glass in seawater SO EARTH AND PLANETARY SCIENCE LETTERS LA English DT Article DE biogeochemistry; volcanic glass; water-rock interaction ID BASALTIC GLASS; OCEANIC-CRUST; IRON AB We studied the effects of biological mediation on the dissolution of basaltic glass in seawater. Experiments with typical seawater microbial populations were contrasted with a sterile control, and reactions were monitored chemically and isotopically. Biologically mediated experiments produce twice the mass of authigenic phases than abiotic experiments and the phases are different. Abiotic alteration of glass dissolves basaltic Si and Ca and scavenges seawater Mg, while biotic alteration removes Ca from seawater. Such opposing behavior of Ca and Mg in biotic and abiotic alteration of basaltic glass may have important implications for the carbon cycle and the exchange processes between ocean crust and seawater. Sr-87/Sr-86 data of glass and alteration products suggest that biological mediation enhances both the diffusion of seawater Sr into glass by a factor of 3-4, and the dissolution of basaltic Sr into seawater by a factor of 20-40. The dependence of chemical exchange processes between seawater and glass on biological activity implies that chemical fluxes from water-rock interaction at low temperatures may change as life on Earth evolves. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Univ Calif San Diego, Scripps Inst Oceanog, La Jolla, CA 92093 USA. Free Univ Amsterdam, Dept Earth Sci, NL-1081 HV Amsterdam, Netherlands. Univ Calif Davis, Dept Geol, Davis, CA 95616 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Netherlands Inst Sea Res, NIOZ, NL-1790 AB Den Burg, Netherlands. RP Staudigel, H (reprint author), Univ Calif San Diego, Scripps Inst Oceanog, La Jolla, CA 92093 USA. EM hstaudigel@ucsd.edu RI bourcier, romain/D-6896-2015 OI bourcier, romain/0000-0002-6506-4019 NR 19 TC 45 Z9 49 U1 0 U2 13 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0012-821X J9 EARTH PLANET SC LETT JI Earth Planet. Sci. Lett. PD DEC 15 PY 1998 VL 164 IS 1-2 BP 233 EP 244 DI 10.1016/S0012-821X(98)00207-6 PG 12 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 153CQ UT WOS:000077815900018 ER PT J AU Beasley, TM Dixon, PR Mann, LJ AF Beasley, TM Dixon, PR Mann, LJ TI Tc-99, U-236, and Np-237 in the Snake River Plain aquifer at the Idaho National Engineering and Environmental Laboratory, Idaho Falls, Idaho SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Article ID CL-36 AB The Idaho National Engineering and Environmental Laboratory (INEEL) is located on the eastern Snake River Plain in southeastern Idaho; it is a multipurpose complex operated by the U.S. Department of Energy. Among its installations is the Idaho Chemical Processing Plant (ICPP), a facility designed principally to recover highly enriched uranium (greater than or equal to 93% U-235) from different nuclear fuel types used in naval propulsion, research, and test reactors. Starting in 1952 and continuing until 1984, low-level radioactive waste was discharged from the ICPP directly to the Snake River Plain aquifer by means of an injection well and seepage ponds. Over time, a suite of radionuclides have been measured in the aquifer including H-3, Cl-36, Sr-90, Cs-137, I-129, and Pu isotopes. Reported here are the first measurements of the long-lived radionuclides Tc-99, U-236, and Np-237 in the aquifer and their downgradient concentration changes during water transport through fractured basalt. Like Cl-36, 99Tc behaves conservatively during transport while I-129, U-236, and Np-237 indicate retardation. C1 US DOE, Environm Measurements Lab, New York, NY 10014 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Beasley, TM (reprint author), US DOE, Environm Measurements Lab, 201 Varick St,5th Floor, New York, NY 10014 USA. EM Beasley@eml.doe.gov NR 24 TC 18 Z9 18 U1 0 U2 4 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0013-936X J9 ENVIRON SCI TECHNOL JI Environ. Sci. Technol. PD DEC 15 PY 1998 VL 32 IS 24 BP 3875 EP 3881 DI 10.1021/es980390d PG 7 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 148YD UT WOS:000077561200005 ER PT J AU Efurd, DW Runde, W Banar, JC Janecky, DR Kaszuba, JP Palmer, PD Roensch, FR Tait, CD AF Efurd, DW Runde, W Banar, JC Janecky, DR Kaszuba, JP Palmer, PD Roensch, FR Tait, CD TI Neptunium and plutonium solubilities in a Yucca Mountain groundwater SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Article ID CARBONATE COMPLEXATION; HYDROUS OXIDE; HYDROLYSIS; BEHAVIOR; DIOXONEPTUNIUM(V); 25-DEGREES-C; EQUILIBRIA; ACTINIDES AB Solubilities of neptunium and plutonium were studied in J-13 groundwater (ionic strength of about 3.7 mmol; total dissolved carbonate of 2.8 mmol) from the proposed Yucca Mountain Nuclear Waste Repository site, Nevada, at three different temperatures (25, 60, and 90 degrees C) and pH values (6.0 7.0,and 8.5). Experiments were performed from both over- and undersaturation at defined CO2 partial pressures. The solubility of Np-237 from oversaturation ranged from a high of (9.40 +/- 1.22) x 10(-4) M at pH 6.0 and 60 degrees C to a low of (5.50 +/- 1.97) x 10(-6) M at pH 8.5 and 90 degrees C. The analytical results of solubility experiments from undersaturation (temperatures of 25 and 90 degrees C and pH values 6, 7, and 8.5) converged on these values. The Pu-239/240 solubilities ranged from (4.70 +/- 1.13) x 10(-8) M at pH 6.0 and 25 degrees C to (3.62 +/- 1.14) x 10(-9) M at pH 8.5 and 90 degrees C. In general, both neptunium and plutonium solubilities decreased with increasing pH and temperature. Greenish-brown crystalline Np2O5. xH(2)O was identified as the solubility-limiting solid using X-ray diffraction. A mean thermodynamic solubility product for Np2O5. xH(2)O of log K(sp)degrees = 5.2 +/- 0.8 for the reaction Np2O5. xH(2)O + 2 H+ reversible arrow 2NpO(2)(+) + (x+1)H2O at 25 degrees C was calculated. Sparingly soluble Pu(IV) solids, PuO2. xH(2)O and/or amorphous plutonium(IV) hydroxide/colloids, control the solubility of plutonium in J-13 water. C1 Univ Calif Los Alamos Natl Lab, Chem Sci & Technol Div, Los Alamos, NM 87545 USA. RP Runde, W (reprint author), Univ Calif Los Alamos Natl Lab, Chem Sci & Technol Div, POB 1663, Los Alamos, NM 87545 USA. EM runde@lanl.gov NR 48 TC 59 Z9 60 U1 1 U2 19 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0013-936X J9 ENVIRON SCI TECHNOL JI Environ. Sci. Technol. PD DEC 15 PY 1998 VL 32 IS 24 BP 3893 EP 3900 DI 10.1021/es980591h PG 8 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 148YD UT WOS:000077561200008 ER PT J AU McCarthy, JF Sanford, WE Stafford, PL AF McCarthy, JF Sanford, WE Stafford, PL TI Lanthanide field tracers demonstrate enhanced transport of transuranic radionuclides by natural organic matter SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Article ID HUMIC-ACID; ADSORPTION; EUROPIUM; SORPTION; AQUIFER; SOIL; PH AB Transuranic (TRU) radionuclides buried 25 years ago in shallow un lined disposal trench es in a fractured shale saprolite had been detected in groundwater from downgradient monitoring wells and in surface water seeps. Field observations had suggested the actinide radionuclides were mobilized by natural organic matter(NOM) and rapidly transported with little retardation. A 73-day natural gradient tracer experiment injected trivalent lanthanides (Nd and Eu) as analogues to determine the mechanisms and rates of actinide transport at the field scale. Adsorption isotherms for Am-241 and Eu with saprolite from the site confirmed a very high affinity for adsorption (R > 50 000) in the absence of NOM. However, reactive and nonreactive tracers arrived at approximately the same time along a 10-m long deep flow path, and anion-exchange chromatography and filtration suggested that the mobile lanthanides in groundwater were a NOM complex. Although flow through a shallow flow path was intermittent, reflecting transient recharge events, large storms resulted in coincident peaks of both reactive and nonreactive tracers, suggesting that they migrated at similar rates over distances of 78 m. We conclude that NOM facilitated the almost-unretarded transport of lanthanide tracers and, by analogy, that NOM is facilitating the mobilization and rapid migration of the TRU radionuclides. C1 Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. Colorado State Univ, Dept Earth Resources, Ft Collins, CO 80523 USA. Univ Tennessee, Dept Geol Sci, Knoxville, TN USA. RP McCarthy, JF (reprint author), Oak Ridge Natl Lab, Div Environm Sci, POB 2008,Bethel Valley Rd, Oak Ridge, TN 37831 USA. RI Sanford, William/F-7380-2016 OI Sanford, William/0000-0001-9085-1367 NR 28 TC 77 Z9 79 U1 1 U2 16 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0013-936X J9 ENVIRON SCI TECHNOL JI Environ. Sci. Technol. PD DEC 15 PY 1998 VL 32 IS 24 BP 3901 EP 3906 DI 10.1021/es971004f PG 6 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 148YD UT WOS:000077561200009 ER PT J AU Sigman, ME Schuler, PF Ghosh, MM Dabestani, RT AF Sigman, ME Schuler, PF Ghosh, MM Dabestani, RT TI Mechanism of pyrene photochemical oxidation in aqueous and surfactant solutions SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Article ID POLYCYCLIC AROMATIC-HYDROCARBONS; LASER FLASH-PHOTOLYSIS; RADICAL-CATIONS; OXYGEN; SOLUBILIZATION; ABSORPTION; COMPLEX; SCALE AB The photolysis of pyrene has been studied in water and in Brij 35 micellar media. Photolysis in both media lead to the formation of 1,6- and 1,8-pyrenequinones as stable products. The first step in the photochemical oxidation is proposed to involve an electron transfer from the excited singlet state of pyrene to molecular oxygen in a contact charge-transfer pair. The effects of oxygen and HSCl2 on the photolysis are interpreted as ruling out mechanistic involvement of a triplet state of pyrene, l-Hydroxypyrene is identified as a product of the initial photochemical oxidation. In the optically dilute aqueous solutions, l-hydroxypyrene undergoes further photochemical oxidation to produce 1,6- and 1,8-pyrenequinones. Pyrene photolysis quantum yields are decreased by a factor of approximately 2 in the micellar media relative to the quantum yields determined in water. Fluorescence data suggest that pyrene resides in the micelles among the polyoxyethylene portion of the surfactant and not within the core of the micelle. C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. Univ Tennessee, Dept Civil & Environm Engn, Knoxville, TN 37996 USA. Univ Tennessee, Ctr Environm Biotechnol, Knoxville, TN 37996 USA. RP Sigman, ME (reprint author), Oak Ridge Natl Lab, Div Chem & Analyt Sci, POB 2008,MS 6100, Oak Ridge, TN 37831 USA. NR 36 TC 86 Z9 92 U1 6 U2 34 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0013-936X J9 ENVIRON SCI TECHNOL JI Environ. Sci. Technol. PD DEC 15 PY 1998 VL 32 IS 24 BP 3980 EP 3985 DI 10.1021/es9804767 PG 6 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 148YD UT WOS:000077561200021 ER PT J AU Francis, AJ Dodge, CJ AF Francis, AJ Dodge, CJ TI Remediation of soils and wastes contaminated with uranium and toxic metals SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Article ID CITRATE COMPLEXES; PSEUDOMONAS-FLUORESCENS; X-RAY; BIODEGRADATION; IRON; SPECIATION AB The presence of radionuclides and toxic metals in soils and wastes due to nuclear related activities is a major environmental concern. To restore the contaminated sites, both the radionuclides and toxic metals must be removed. We have developed a comprehensive method to remediate contaminated soils and wastes with the removal and recovery of uranium and toxic metals. The overall process consist of three steps: extraction, biodegradation, and photodegradation. Radionuclides and toxic metals are removed from contaminated soils and wastes by extracting them with citric acid, a natural multidentate complexing agent. Citric acid forms different types of complexes with the transition metals and actinides that may involve the formation of bidentate, tridentate, binuclear, or polynuclear complex species. Several metal-citrate complexes were readily biodegraded by Pseudomonas fluorescens, resulting in the bioprecipitation and recovery of the metals, whereas uranyl citrate, which is recalcitrant to biodegradation, upon exposure to light was photodegraded with the precipitation of uranium as UO3. xH(2)O. For example, uranium was removed from contaminated soils and sludge with >85% efficiency. Biodegradation followed by photodegradation of the citric acid extract resulted in >99% recovery of the extracted uranium. In addition, significant amounts of Al, Ca, Co, Cr, Cu, Mg, Mn, Ni, Pb, Sr, Th, and Zn were also removed during biodegradation of the extract. In this process, the toxic metals and uranium are recovered in separate fractions in concentrated form for recycling or disposal. C1 Brookhaven Natl Lab, Dept Appl Sci, Upton, NY 11973 USA. RP Francis, AJ (reprint author), Brookhaven Natl Lab, Dept Appl Sci, Upton, NY 11973 USA. NR 35 TC 65 Z9 66 U1 1 U2 30 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0013-936X J9 ENVIRON SCI TECHNOL JI Environ. Sci. Technol. PD DEC 15 PY 1998 VL 32 IS 24 BP 3993 EP 3998 DI 10.1021/es9803310 PG 6 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 148YD UT WOS:000077561200023 ER PT J AU Bennett, DH McKone, TE Matthies, M Kastenberg, WE AF Bennett, DH McKone, TE Matthies, M Kastenberg, WE TI General formulation of characteristic travel distance for semivolatile organic chemicals in a multimedia environment SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Article ID GLOBAL DISTRIBUTION; DRY DEPOSITION; MODEL; SOIL; VEGETATION; DIOXINS; 2,3,7,8-TETRACHLORODIBENZO-P-DIOXIN; PHOTODEGRADATION; DIBENZOFURANS; UNCERTAINTY AB A relatively simple but informative methodology is introduced to determine the characteristic travel distance (CTD) for airborne semivolatile organic pollutants. The CTD is derived from a moving Lagrangian cell (representing the air) and a nonmoving compartment (representing soil or vegetation). The methodology is expanded to a fugacity based steady-state multimedia environmental framework including air, vegetation, and soil. Chemical transformations in air as well as partitioning to, and transformation in, vegetation and soil are considered. Concentrations are determined by interactions among the compartments and transformation rates. This method is most appropriate for continuous, large nonpoint emissions (such as emissions from an urban airshed). A case study for 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) reveals that the CTD is on the same order of magnitude as the typical distance between urban centers. Vegetation is important for defining the regional transport processes for TCDD. C1 Univ Calif Berkeley, Dept Nucl Engn, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Mech Engn, Berkeley, CA 94720 USA. Univ Calif Berkeley, Sch Publ Hlth, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Environm Energy Technol Div, Berkeley, CA 94720 USA. Univ Osnabruck, Inst Environm Syst Res, D-4500 Osnabruck, Germany. RP Kastenberg, WE (reprint author), Univ Calif Berkeley, Dept Nucl Engn, Berkeley, CA 94720 USA. NR 40 TC 109 Z9 117 U1 1 U2 19 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0013-936X J9 ENVIRON SCI TECHNOL JI Environ. Sci. Technol. PD DEC 15 PY 1998 VL 32 IS 24 BP 4023 EP 4030 DI 10.1021/es980328g PG 8 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 148YD UT WOS:000077561200028 ER PT J AU Deweerd, W Koops, G Pattyn, H Myers, SM Aselage, TL Headley, TJ Petersen, GA AF Deweerd, W Koops, G Pattyn, H Myers, SM Aselage, TL Headley, TJ Petersen, GA TI Mossbauer study of the proximity gettering of ion-implanted Co-57 impurities by B-Si precipitates in Si SO EUROPHYSICS LETTERS LA English DT Article ID SPECTROSCOPY; SILICON; COBALT; CAVITIES AB We have studied the gettering of ion-implanted Co-57 impurities to amorphous B-Si precipitates in B-implanted c-Si using Mossbauer spectroscopy in conjunction with Secondary Ion Mass Spectroscopy and Transmission Electron Microscopy. Under high-temperature annealing, the Co atoms migrate from their as-implanted state to a gettered state at the B-Si precipitates in the B-implanted layer, while no association between the Co impurities and unprecipitated B is observed. The gettered Co atoms clearly occupy a non-metal-silicide site. The Mossbauer spectrum displays a pronounced quadrupole splitting, closely conforming to the spectrum observed for bulk crystalline B3Si implanted with Co. We therefore tentatively argue that the gettered atoms reside at solution sites within the precipitates and not in their periphery, in agreement with previous indications. C1 Katholieke Univ Leuven, Inst Kern Stralingsfys, B-3001 Louvain, Belgium. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Deweerd, W (reprint author), Katholieke Univ Leuven, Inst Kern Stralingsfys, Celestijnenlaan 200D, B-3001 Louvain, Belgium. NR 12 TC 2 Z9 2 U1 0 U2 0 PU E D P SCIENCES PI LES ULIS CEDEXA PA 7, AVE DU HOGGAR, PARC D ACTIVITES COURTABOEUF, BP 112, F-91944 LES ULIS CEDEXA, FRANCE SN 0295-5075 J9 EUROPHYS LETT JI Europhys. Lett. PD DEC 15 PY 1998 VL 44 IS 6 BP 707 EP 713 DI 10.1209/epl/i1998-00529-8 PG 7 WC Physics, Multidisciplinary SC Physics GA 149BP UT WOS:000077585500005 ER PT J AU Oatis, S Imre, D McGraw, R Xu, J AF Oatis, S Imre, D McGraw, R Xu, J TI Heterogeneous nucleation of a common atmospheric aerosol: Ammonium sulfate SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID DENVER; PARTICLES; DROPLETS AB Natural and anthropogenic aerosols have a direct impact on the earth's radiative balance. Many of the common atmospheric aerosols contain hygroscopic salts and therefore their physical state and composition are sensitive to the relative humidity. The phase of the aerosol particle will dramatically affect the relative rates of atmospheric reactions, and radiative properties such as scattering and optical activity. In order to understand these atmospheric processes and provide accurate input for global modeling, it is imperative that these phase transitions be well defined. It is thought that the degree of metastability is influenced by the presence of foreign particulate matter. These solid impurities are predicted to reduce the barrier of nucleation by providing a surface upon which heterogeneous nucleation can be catalyzed. We report the results of CaCO3 and BaSO4 solid impurities on the efflorescence of(NH4)(2)SO4-H2O micro-droplets. The results show that both solid impurities act as catalysts for heterogeneous nucleation by causing a decrease in the degree of metastability at the efflorescence point. BaSO4 does not prove to be significantly more efficient than CaCO3 in spite of having the same crystalline structure and similar lattice parameters as in (NH4)(2)SO4. C1 Southampton Coll, Dept Nat Sci, Southampton, NY 11968 USA. Brookhaven Natl Lab, Dept Appl Sci, Environm Chem Div, Upton, NY 11973 USA. SUNY Stony Brook, Dept Marine Sci, Stony Brook, NY 11790 USA. RP Oatis, S (reprint author), Southampton Coll, Dept Nat Sci, Southampton, NY 11968 USA. NR 22 TC 19 Z9 21 U1 1 U2 7 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD DEC 15 PY 1998 VL 25 IS 24 BP 4469 EP 4472 DI 10.1029/1998GL900199 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 154HD UT WOS:000077882600020 ER PT J AU Mather, JH Ackerman, TP Jensen, MP Clements, WE AF Mather, JH Ackerman, TP Jensen, MP Clements, WE TI Characteristics of the atmospheric state and the surface radiation budget at the tropical western Pacific ARM site SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID TOGA COARE; CLOUD AB The Department of Energy's Atmospheric Radiation Measurement (ARM) program has been operating a radiation and cloud observing station in the tropical western Pacific (TWP) since October, 1996. This station includes instruments for measuring the surface radiation budget, characteristics of the atmospheric column that affect that budget, and surface meteorological parameters. Our purpose here is both to introduce some of the fundamental characteristics of the tropical western Pacific region and to show some interesting properties of the data that have emerged from our analyses thus far. The column concentration of water vapor is very high in this region and dominates the downward flux of infrared at the surface. For shortwave radiation, clouds dominate the surface budget. We have compared the surface shortwave cloud forcing from the ARM site with previous observations from this region. Finally, we have examined the vertical distribution of clouds in periods of active and suppressed convection and find interesting contrasts between these regimes. C1 Penn State Univ, Dept Meteorol, University Pk, PA 16802 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM USA. RP Mather, JH (reprint author), Penn State Univ, Dept Meteorol, 503 Walker Bldg, University Pk, PA 16802 USA. NR 11 TC 16 Z9 16 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD DEC 15 PY 1998 VL 25 IS 24 BP 4513 EP 4516 DI 10.1029/1998GL900196 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 154HD UT WOS:000077882600031 ER PT J AU Amano, H Iwaya, M Kashima, T Katsuragawa, M Akasaki, I Han, J Hearne, S Floro, JA Chason, E Figiel, J AF Amano, H Iwaya, M Kashima, T Katsuragawa, M Akasaki, I Han, J Hearne, S Floro, JA Chason, E Figiel, J TI Stress and defect control in GaN using low temperature interlayers SO JAPANESE JOURNAL OF APPLIED PHYSICS PART 2-LETTERS LA English DT Article DE GaN; low temperature deposited layer; stress; strain ID GROWTH; FILMS; DISLOCATIONS AB In organometallic vapor phase epitaxial growth of GaN on sapphire, the role of the low-temperature-deposited interlayers inserted between high-temperature-grown GaN layers was investigated by in situ stress measurement, X-ray diffraction, and transmission electron microscopy. Insertion of a series of low temperature GaN interlayers reduces the density of threading dislocations while simultaneously increasing the tensile stress during growth, ultimately resulting in cracking of the GaN film. Low temperature AW interlayers were found to be effective in suppressing cracking by reducing tensile stress. Thr interlayer approach permits tailoring of the film stress to optimize film structure and properties. C1 Meijo Univ, Tempaku Ku, Nagoya, Aichi 4688502, Japan. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Amano, H (reprint author), Meijo Univ, Tempaku Ku, Nagoya, Aichi 4688502, Japan. NR 20 TC 112 Z9 114 U1 3 U2 40 PU JAPAN J APPLIED PHYSICS PI MINATO-KU TOKYO PA DAINI TOYOKAIJI BLDG 24-8 SHINBASHI 4-CHOME, MINATO-KU TOKYO, 105, JAPAN SN 0021-4922 J9 JPN J APPL PHYS 2 JI Jpn. J. Appl. Phys. Part 2 - Lett. PD DEC 15 PY 1998 VL 37 IS 12B BP L1540 EP L1542 DI 10.1143/JJAP.37.L1540 PG 3 WC Physics, Applied SC Physics GA 159TD UT WOS:000078189800015 ER PT J AU Vijayalakshmi, S Grebel, H Iqbal, Z White, CW AF Vijayalakshmi, S Grebel, H Iqbal, Z White, CW TI Artificial dielectrics: Nonlinear properties of Si nanoclusters formed by ion implantation in SiO2 glassy matrix SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID SILICON NANOCLUSTERS; OPTICAL PROPERTIES; NANOCRYSTALS; BEAM AB The nonlinear optical properties of Si nanoclusters formed by ion implantation into an SiO2 glassy matrix and followed by annealing have been studied at lambda = 532 nm and lambda = 355 nm by use of Z-scan and pump-probe techniques. These have been compared to the nonlinear properties of laser-ablated Si films. At relatively large intensities (>1 MW/cm(2)) the absolute nonlinear values for these isolated nanoclusters were comparable to those obtained for laser-ablated samples although opposite in sign. Laser-ablated samples showed a much larger effect at relatively low intensities (<1 MW/cm(2)), while the ion-implanted films showed almost none. Lifetime constants were in the range of 3-5 ns for all samples. (C) 1998 American Institute of Physics. [S0021-8979(98)07324-1]. C1 New Jersey Inst Technol, Dept Elect & Comp Engn, Opt Waveguide Lab, Newark, NJ 07102 USA. Allied Signal Inc, Aerospace Technol, Morristown, NJ 07962 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Grebel, H (reprint author), New Jersey Inst Technol, Dept Elect & Comp Engn, Opt Waveguide Lab, Newark, NJ 07102 USA. NR 14 TC 34 Z9 36 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD DEC 15 PY 1998 VL 84 IS 12 BP 6502 EP 6506 DI 10.1063/1.369019 PG 5 WC Physics, Applied SC Physics GA 144BJ UT WOS:000077293100003 ER PT J AU Forbes, JW Lemar, ER AF Forbes, JW Lemar, ER TI Detonation wave velocity and curvature of a plastic-bonded, nonideal explosive PBXN-111 as a function of diameter and confinement SO JOURNAL OF APPLIED PHYSICS LA English DT Article AB Detonation velocities and wave front curvatures are measured on various diameter cylinders of PBXN-111 (RDX/AP/Al/HTPB binder with 20/43/25/12 weight percent). The cylinders are either unconfined or encased in 5-mm-thick brass tubes. In all experiments with brass tubes (diameters from 19 to 100 mm) the detonation velocity of PBXN-111 was affected by the confinement. Steady detonation waves propagated in brass encased charges with diameters as small as 19 mm, which is about half of the 37.1 mm failure diameter for unconfined PBXN-111. The radii of curvature at the center of the detonation wave fronts ranged from 52 to 480 mm for charge diameters from 25 to 100 mm, respectively. Detonation velocity as a function of radius of curvature at the wave's center is represented by a single curve for both cased and uncased cylindrical charges. The difference in the axial position of the detonation wave at the center of the charge and at the edge of the charge (i. e., lag distance) are between 1.6 and 6.7 mm. The angles between the detonation wave fronts and the brass/charge interfaces are between 73 degrees and 82 degrees while the angles at the cylindrical free surface for the uncased charges are between 61 degrees and 64 degrees. Calculation of this angle for brass encased charges using oblique shock equations and assuming no reaction in the shock front resulted in angles 8 degrees higher than measured except for the 100-mm-diam charge which was in agreement. The calculated angles for the uncased charge are in agreement with the measured values. [S0021-8979(98)06224-0]. C1 USN, Ctr Surface Warfare, Div Indian Head, Indian Head, MD USA. RP Forbes, JW (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 26 TC 4 Z9 4 U1 2 U2 5 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD DEC 15 PY 1998 VL 84 IS 12 BP 6600 EP 6605 DI 10.1063/1.369033 PG 6 WC Physics, Applied SC Physics GA 144BJ UT WOS:000077293100018 ER PT J AU Kunchur, MN Askew, TR AF Kunchur, MN Askew, TR TI Hysteretic internal fields and critical currents in polycrystalline superconductors SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID TRANSPORT CRITICAL-CURRENT; CRITICAL-CURRENT-DENSITY; BA-CU-O; CRITICAL CURRENT IRREVERSIBILITY; FLUX; DEPENDENCE; YBA2CU3O7; BEHAVIOR; CERAMICS; BULK AB The transport critical current J(c) in a polycrystalline superconductor is a hysteretic function of applied magnetic field H-0 due to flux trapping by grains. This effect has been observed by several groups and attempts have been made to calculate the intergranular field H-i as a function of the applied H-0 in terms of an effective geometrical demagnetization factor D. In general a first-principles calculation of D is very difficult, and furthermore, D is not constant but is itself a hysteretic function of H-0. We develop a self-consistent scheme to extract the D and H-i directly from the J(c)(H-0) data itself. Our model exploits the fact that there are two field ranges for which the demagnetizing field is a simple function of H-0. At low virgin fields, in the Meissner state, the susceptibility chi(v) approximate to 1/4 pi is well defined, leading to a multiplicative correction: H-i = H-0/(1 + D4 pi chi(v)). For fields that have returned from high values, a complete critical state is established and M is well defined - although chi(v) is unknown. This leads to an additive correction: H-i = H-0 - D4 pi M for the total field. By matching J(c) data in increasing and decreasing fields that satisfy these special cases, it is possible to extract the relevant parameters of the problem without detailed knowledge of the demagnetization geometry. We use this model to analyze data measured on sintered YBa2Cu3O7 superconductive rods. (C) 1998 American Institute of Physics. [S0021- 8979(98)03824-9]. C1 Univ S Carolina, Dept Phys & Astron, Columbia, SC 29208 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Kalamazoo Coll, Dept Phys, Kalamazoo, MI 49006 USA. RP Kunchur, MN (reprint author), Univ S Carolina, Dept Phys & Astron, Columbia, SC 29208 USA. NR 38 TC 16 Z9 16 U1 1 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD DEC 15 PY 1998 VL 84 IS 12 BP 6763 EP 6767 DI 10.1063/1.369005 PG 5 WC Physics, Applied SC Physics GA 144BJ UT WOS:000077293100043 ER PT J AU Willard, MA Laughlin, DE Mchenry, ME Thoma, D Sickafus, K Cross, JO Harris, VG AF Willard, MA Laughlin, DE Mchenry, ME Thoma, D Sickafus, K Cross, JO Harris, VG TI Structure and magnetic properties of (Fe0.5Co0.5)(88)Zr7B4Cu1 nanocrystalline alloys SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID HIGH SATURATION MAGNETIZATION; TRANSITION-METAL ALLOYS; M-B M=ZR; FE-ZR-B; GRAIN-SIZE; DEPENDENCE AB The development of Fe73.5Si13.5B9Nb3Cu1 (FINEMET) by Yoshizawa et al. and Fe88Zr7B4Cu1 (NANOPERM) by Inoue et al. have shown that nanocrystalline microstructures can plan an important role in the production of materals with outstanding soft magnetic properties. The FINEMET and NANOPERM materials rely on nanocrystalline alpha-Fe3Si and alpha-Fe, respectively, for their soft magnetic properties. The magnetic properties of a new class of nanocrystalline magnets are described herein. These alloys with a composition of (Fe, Co)-M-B-Cu (where M = Zr and Hf) are based on the alpha- and alpha'-FeCo phases, have been named HITPERM magnets, and offer large magnetic inductions to elevated temperatures. This report focuses on thermomagnetic properties, alternating current (ac) magnetic response, and unambiguous evidence of alpha'-FeCo as the nanocrystalline ferromagnetic phase, as supported by synchrotron x-ray diffraction. Synchrotron data have distinguished between the HITPERM alloy, with nanocrystallites having a B2 structure data have distinguished between the HITPERM alloy, with nanocrystallites having a B2 structure from the FINEMET alloys, with the D0(3) structure, and NANOPERM alloys, with the A2 structure. Thermomagnetic data shows high magnetization to persist to the alpha --> gamma phase transformation at 980 degrees C. The room temperature ac permeability has been found to maintain a high value of 1800 up to a frequency of similar to 2 kHz. The room temperature core loss has also been shown to be competitive with that of commercial high temperature alloys with a value of 1 W/g at B-s = 10 kG and f = 1 kHz. (C) 1998 American Institute of Physics. [S0021-8979(98)03024-2]. C1 Carnegie Mellon Univ, Dept Mat Sci & Engn, Pittsburgh, PA 15213 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. USN, Res Lab, Washington, DC 20375 USA. RP Willard, MA (reprint author), Carnegie Mellon Univ, Dept Mat Sci & Engn, Pittsburgh, PA 15213 USA. RI Willard, Matthew/A-8492-2009; Harris, Vincent/A-8337-2009; McHenry, Michael/B-8936-2009 OI Willard, Matthew/0000-0001-5052-8012; NR 12 TC 291 Z9 312 U1 3 U2 77 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD DEC 15 PY 1998 VL 84 IS 12 BP 6773 EP 6777 DI 10.1063/1.369007 PG 5 WC Physics, Applied SC Physics GA 144BJ UT WOS:000077293100045 ER PT J AU Marshall, GW Wu-Magidi, IC Watanabe, LG Inai, N Balooch, M Kinney, JH Marshall, SJ AF Marshall, GW Wu-Magidi, IC Watanabe, LG Inai, N Balooch, M Kinney, JH Marshall, SJ TI Effect of citric acid concentration on dentin demineralization, dehydration, and rehydration: Atomic force microscopy study SO JOURNAL OF BIOMEDICAL MATERIALS RESEARCH LA English DT Article DE dentin; demineralization; shrinkage; rehydration; atomic force microscopy ID DIMENSIONAL CHANGES; INTERDIFFUSION ZONE; ADHESIVE; HEMA AB Most current dentin bonding procedures use acid etchants to partially demineralize the dentin structure and provide pathways for resin infiltration. This study determined the recession rates of peritubular dentin and intertubular dentin as a function of pH during demineralization in citric acid solutions (0.0005-2.5M) and the effects of dehydration and rehydration on the partially demineralized dentin. Polished dentin disks were prepared with an internal reference layer and were studied at specific intervals for citric acid etching between pH 1 and 3.4 in an atomic force microscope. Peritubular dentin etched rapidly and Linearly with time until it could no longer be measured. The intertubular surface began etching at nearly the same rate, hut then recession slowed for all concentrations and stabilized after recession of less than 1 mu m for all but the pH 1 solution. The decrease in recession was attributed to the Limitation of contraction of the demineralized collagen scaffold as long as it remained hydrated. Dehydration following etching resulted in significant collapse of the surface, changes in roughness, and a slight decrease in tubule diameter for samples etched for 30 min. Measurements could not be made of the collapse for low pH samples, because shrinkage stresses disrupted the integrity of the reference layer. On rehydration, the dehydrated surfaces underwent an expansion up to the level seen after etching and tubule diameters returned to the etched values. These results indicate that the collapse of demineralized matrix is almost totally recoverable on rehydration. (C) 1998 John Wiley & Sons, Inc. C1 Univ Calif San Francisco, Div Biomat Sci, Dept Restorat Dent, San Francisco, CA 94143 USA. Univ Calif Lawrence Livermore Natl Lab, Dept Chem & Mat Sci, Livermore, CA 94550 USA. RP Marshall, GW (reprint author), Univ Calif San Francisco, Div Biomat Sci, Dept Restorat Dent, 707 Parnassus Ave,Box 0758, San Francisco, CA 94143 USA. FU NIDCR NIH HHS [R01 DE11526, P01 DE09859] NR 29 TC 38 Z9 38 U1 1 U2 2 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0021-9304 J9 J BIOMED MATER RES JI J. Biomed. Mater. Res. PD DEC 15 PY 1998 VL 42 IS 4 BP 500 EP 507 DI 10.1002/(SICI)1097-4636(19981215)42:4<500::AID-JBM4>3.0.CO;2-L PG 8 WC Engineering, Biomedical; Materials Science, Biomaterials SC Engineering; Materials Science GA 135HJ UT WOS:000076795500004 PM 9827672 ER PT J AU Baer, R Head-Gordon, M AF Baer, R Head-Gordon, M TI Electronic structure of large systems: Coping with small gaps using the energy renormalization group method SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID BINDING MOLECULAR-DYNAMICS; DENSITY-FUNCTIONAL CALCULATIONS; SIZE SCALING METHODS; TIGHT-BINDING; LOCALIZED ORBITALS; MATRIX METHOD; MODEL; SILICON; EIGENFUNCTIONS; EIGENVALUES AB A newly developed energy renormalization-group method for electronic structure of large systems with small Fermi gaps within a tight-binding framework is presented in detail. A telescopic series of nested Hilbert spaces is constructed, having exponentially decreasing dimensions and electrons, for which the Hamiltonian matrices have exponentially converging energy ranges focusing to the Fermi level and in which the contribution to the density matrix is a sparse contribution. The computational effort scales near linearly with system size even when the density matrix is highly nonlocal. This is illustrated by calculations on a model metal, a small radius carbon-nanotube and a two-dimensional puckered sheet polysilane semiconductor. (C) 1998 American Institute of Physics. [S0021-9606(98)31046-6]. C1 Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Dept Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Chem Sci, Berkeley, CA 94720 USA. Hebrew Univ Jerusalem, Dept Phys Chem, IL-91904 Jerusalem, Israel. RP Baer, R (reprint author), Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Dept Chem, Berkeley, CA 94720 USA. NR 68 TC 22 Z9 22 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-9606 EI 1089-7690 J9 J CHEM PHYS JI J. Chem. Phys. PD DEC 15 PY 1998 VL 109 IS 23 BP 10159 EP 10168 DI 10.1063/1.477709 PG 10 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 147BZ UT WOS:000077469200009 ER PT J AU Parks, EK Kerns, KP Riley, SJ AF Parks, EK Kerns, KP Riley, SJ TI The structure of Ni-39 SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID TRANSITION-METAL CLUSTERS; BINDING MOLECULAR-DYNAMICS; SMALL NICKEL CLUSTERS; SMALL NI-N; MAGNETIC-PROPERTIES; IRON CLUSTERS; ELECTRONIC-STRUCTURE; N-2; CO; ADSORPTION AB The geometrical structure of Ni-39 is probed via molecular adsorption of nitrogen on its surface. Nitrogen uptake patterns are determined at various reaction temperatures, and the results are interpreted in terms of the number and nature of nitrogen binding sites on possible structures. It is found that an adsorbate-induced isomerization occurs at partial nitrogen coverage, but that at saturation a reverse isomerization returns the cluster to its initial structure. The two lowest energy structures calculated by Wetzel and DePristo [T. L. Wetzel and A. E. DePristo, J. Chem. Phys. 105, 572 (1996)] are completely consistent with the observed saturation and isomerization behavior. The structures consist of atom caps packed around a central pentagonal bipyramid, and reflect a marked change from the octahedral structure determined earlier for Ni-38. [S0021-9606(98)70947-X]. C1 Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. RP Parks, EK (reprint author), Argonne Natl Lab, Div Chem, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 47 TC 28 Z9 29 U1 1 U2 7 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD DEC 15 PY 1998 VL 109 IS 23 BP 10207 EP 10216 DI 10.1063/1.477715 PG 10 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 147BZ UT WOS:000077469200015 ER PT J AU Skokov, S Qi, JX Bowman, JM Yang, CY Gray, SK Peterson, KA Mandelshtam, VA AF Skokov, S Qi, JX Bowman, JM Yang, CY Gray, SK Peterson, KA Mandelshtam, VA TI Accurate variational calculations and analysis of the HOCl vibrational energy spectrum SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID LASER-ABSORPTION SPECTROSCOPY; UNIMOLECULAR DISSOCIATION; INTRAMOLECULAR DYNAMICS; FILTER-DIAGONALIZATION; BOUND-STATES; BASIS-SETS; HIERARCHICAL ANALYSIS; HYPOCHLOROUS ACID; LANCZOS-ALGORITHM; FLOPPY MOLECULES AB Large scale variational calculations for the vibrational states of HOCl are performed using a recently developed, accurate nb initio potential energy surface. Three different approaches for obtaining vibrational states are employed and contrasted; a truncation/recoupling scheme with direct diagonalization, the Lanczos method, and Chebyshev iteration with filter diagonalization. The complete spectrum of bound states for nonrotating HOCl is computed and analyzed within a random matrix theory framework. This analysis indicates almost entirely regular dynamics with only a small degree of chaos. The nearly regular spectral structure allows us to make assignments for the most significant part of the spectrum, based on analysis of coordinate expectation values and eigenfunctions. Ground state dipole moments and dipole transition probabilities are also calculated using accurate ab initio data. Computed values are in good agreement with available experimental data. Some exact rovibrational calculations for J = 1, including Coriolis coupling, are performed. The exact results are nearly identical with those obtained from the adiabatic rotation approximation and very close to those from the centrifugal sudden approximation, thus indicating a very small degree of asymmetry and Coriolis coupling for the HOCl molecule. (C) 1998 American Institute of Physics. [S0021-9606(98)00947-7]. C1 Emory Univ, Dept Chem, Atlanta, GA 30322 USA. Emory Univ, Cherry L Emerson Ctr Sci Computat, Atlanta, GA 30322 USA. Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. Washington State Univ, Dept Chem, Richland, WA 99352 USA. Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. Univ Calif Irvine, Dept Chem, Irvine, CA 92697 USA. RP Bowman, JM (reprint author), Emory Univ, Dept Chem, 1515 Pierce Dr, Atlanta, GA 30322 USA. EM bowman@euch3g.chem.emory.edu NR 75 TC 72 Z9 73 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD DEC 15 PY 1998 VL 109 IS 23 BP 10273 EP 10283 DI 10.1063/1.477723 PG 11 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 147BZ UT WOS:000077469200023 ER PT J AU Furlan, A Hall, GE AF Furlan, A Hall, GE TI Photoproducts ejected from liquid surfaces: The importance of photochemical, diffusional, kinetic, and surface structural effects SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID 248 NM; PHOTODISSOCIATION DYNAMICS; METHYL-IODIDE; 304 NM; CH3I; CF3I; COLLISIONS; LASER AB Gas-phase products of liquid surface photochemistry in high vacuum were analyzed by time-of-flight/quadrupole mass spectroscopy. A thin liquid film of a long-chain alkyl iodide, C18H37I, dissolved in squalane (C30H62) was irradiated with nanosecond laser pulses at 275 nm. The photoproducts leaving the liquid after a low-fluence laser pulse (0.5 mJ/cm(2)) were I, HI, and I-2 Since these species may desorb at times delayed by diffusion in the liquid phase, time-of-flight profiles were also recorded using a chopper wheel in front of the surface. This allowed a reconstruction of the time-dependent flux from the surface. The flight time distributions were compared to model calculations which take into account laser photolysis of C18H37I, diffusion and surface evaporation of I, HI, and I-2, and the condensed-phase kinetics of radical reactions, and allow for a component of direct photodissociation of surface layer molecules, leading to hyperthermal I atoms. Simulations based on a comprehensive kinetic scheme are in good agreement with our measurements, with no specific surface processes other than evaporation of thermalized species formed at, or diffusing to the surface. However, compared to results previously found for liquid C2H5I, the caging of the geminate pair is much stronger in our system, and the fraction of I atoms promptly reacting to HI is smaller. The absence of prompt hyperthermal I fragments is interpreted by a preferential orientation of the C18H37I molecules in the topmost liquid layer with the I atom pointing into the liquid. The sensitivity of the method is discussed with respect to surface-specific processes, as well as primary and secondary radical reactions occurring in the bulk liquid. (C) 1998 American Institute of Physics. [S0021-9606(98)70647-6]. C1 Univ Zurich, Inst Phys Chem, CH-8057 Zurich, Switzerland. Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. RP Furlan, A (reprint author), Univ Zurich, Inst Phys Chem, Winterthurerstr 190, CH-8057 Zurich, Switzerland. RI Hall, Gregory/D-4883-2013 OI Hall, Gregory/0000-0002-8534-9783 NR 33 TC 15 Z9 15 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD DEC 15 PY 1998 VL 109 IS 23 BP 10390 EP 10399 DI 10.1063/1.477694 PG 10 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 147BZ UT WOS:000077469200035 ER PT J AU Wilson, WD Schaldach, CM AF Wilson, WD Schaldach, CM TI Adsorption of molecules on a charged polarizable surface in an electrolyte SO JOURNAL OF COLLOID AND INTERFACE SCIENCE LA English DT Article DE quantum chemical; Poisson-Boltzmann; Gouy-Chapman; molecular binding ID HYDROGEN-SULFIDE; COPPER; CORROSION; CHEMISTRY; SILVER; FILMS; GAS AB We present a method for the calculation of the binding and rotational energies of neutral (H2S) and charged (HS-) molecules impinging upon a charged and polarizable (Cu [100]) surface in the presence of an electrolyte. A molecular surface is constructed surrounding the H2S and HS- molecules forming boundary elements. A coupled Schrodinger-Poisson-Boltzmann iterative procedure treats the electronic structure of the molecules at the 6-31G**/MP2 level of theory and includes solvation effects through the single and double layers of charge induced by the electronic distribution. The molecule, together with its charged layers, forms a molecular single and double layer, an object which then interacts with a polarizable Gouy-Chapman plane within the electrolyte. The induced charge at the molecular surface resulting from this external electric field is obtained by solving a second set of boundary element equations. The induced polarization of the solid surface created by the impinging molecular ion is treated by a modified method of images. Repulsive interactions between the atoms of the molecule and those of the surface are obtained using a rigid-ion Hartree-Fock method. Binding energies of the molecule to the surface are determined as a function of the real surface charge imposed and also the ionic strength of the solution. It is found that surface charges can completely (180 degrees) reorient these molecules and that the counterions in the solution can completely screen binding effects of even large surface charges. Solid surface polarization can be significant in low dielectric constant solvents and is also reduced by counterions. (C) 1998 Academic Press. C1 Sandia Natl Labs, Livermore, CA 94550 USA. Univ Calif Berkeley, Berkeley, CA 94720 USA. RP Wilson, WD (reprint author), Sandia Natl Labs, Org 8700,MS 9904, Livermore, CA 94551 USA. NR 25 TC 3 Z9 3 U1 1 U2 4 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0021-9797 J9 J COLLOID INTERF SCI JI J. Colloid Interface Sci. PD DEC 15 PY 1998 VL 208 IS 2 BP 546 EP 554 DI 10.1006/jcis.1998.5815 PG 9 WC Chemistry, Physical SC Chemistry GA 148QT UT WOS:000077544000022 ER PT J AU Maltrud, ME Smith, RD Semtner, AJ Malone, RC AF Maltrud, ME Smith, RD Semtner, AJ Malone, RC TI Global eddy-resolving ocean simulations driven by 1985-1995 atmospheric winds SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID WESTERN BOUNDARY CURRENT; ANTARCTIC CIRCUMPOLAR CURRENT; GENERAL-CIRCULATION MODEL; BRUNT-VAISALA FREQUENCY; SEA-SURFACE TOPOGRAPHY; NORTH-ATLANTIC OCEAN; HEAT-TRANSPORT; ROSSBY RADII; VARIABILITY; RESOLUTION AB Results are presented from a high-resolution global ocean model that is driven through three decadal cycles of increasingly realistic prescribed atmospheric forcing from the period 1985-1995. The model used (the Parallel Ocean Program) is a z level primitive equation model with active thermohaline dynamics based on the formulation of Bryan [1969] rewritten for massively parallel computers. Improvements to the model include an implicit free-surface formulation of the barotropic mode [Dukowicz and Smith, 1994] and the use of pressure averaging for increasing the numerical time step. This study extends earlier 0.5 degrees simulations of Semtner and Chervin [1992] to higher horizontal resolution with improved treatments of ocean geometry and surface forcing. The computational grid is a Mercator projection covering the global ocean from 77 degrees N to 77 degrees S and has 20 vertical levels. Three successive simulations have been performed on the CM-5 Connection Machine system at Los Alamos using forcing fields from the European Centre for Medium-Range Weather Forecasts (ECMWF). The first run uses monthly wind stresses for 1985-1995 and restoring of surface temperature and salinity to the Levitus [1982] seasonal climatology. The second run is the same but with 3 day-averaged rather than monthly averaged wind stress fields, and the third is the same as the second but uses the monthly climatological ECMWF heat fluxes of Barnier et al. [1995] instead of restoring to climatological sea surface temperatures. Many features of the wind-driven circulation are well represented in the model solutions, such as the overall current patterns, the numerous regions of hydrodynamic instability which correspond to these observed by satellite altimetry, and the filamented structure of the Antarctic Circumpolar Current. However, some features such as the separation points of the Gulf Stream and Kuroshio and the transport through narrow passages such as the Florida Straits are clearly inaccurate and indicate that still higher resolution may be required to correct these deficiencies. Water mass properties and some aspects of the thermohaline circulation are also not always well reproduced, which is partly due to the relatively short length of the integrations. The use of the ECMWF heat fluxes, rather than restoring to climatological surface temperatures, leads to stronger and more realistic surface and deep western boundary currents (primarily in the Atlantic) as well as more realistic meridional heat transport; this is primarily because the equilibrium meridional heat transport implied by the ECMWF surface fluxes is quite large. The ECMWF heat fluxes also produce improved seasonal cycles of sea surface temperature and height in both the northern and southern hemispheres. The 3-day wind forcing gives rise to modes of model variability that are clearly seen in synoptic observations, such as the large-scale 20-100-day oscillations seen in the TOPEX/POSEIDON data, which are barotropic oscillations induced by the high-frequency wind forcing. Additional studies on other aspects of the simulations described here are being conducted by a variety of investigators, and some of these are briefly described. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. USN, Postgrad Sch, Dept Oceanog, Monterey, CA 93943 USA. RP Maltrud, ME (reprint author), Los Alamos Natl Lab, MS B216, Los Alamos, NM 87545 USA. EM maltrud@lanl.gov NR 69 TC 123 Z9 129 U1 1 U2 4 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-OCEANS JI J. Geophys. Res.-Oceans PD DEC 15 PY 1998 VL 103 IS C13 BP 30825 EP 30853 DI 10.1029/1998JC900013 PG 29 WC Oceanography SC Oceanography GA 155YR UT WOS:000077974900014 ER PT J AU De Arellano-Lopez, AR Mcmann, MA Singh, JP Martinez-Fernandez, J AF De Arellano-Lopez, AR Mcmann, MA Singh, JP Martinez-Fernandez, J TI Microstructure and room-temperature mechanical properties of Si3N4 with various alpha/beta phase ratios SO JOURNAL OF MATERIALS SCIENCE LA English DT Article ID BETA-SILICON NITRIDE; FRACTURE-TOUGHNESS; ELASTIC PROPERTIES; CERAMICS; TRANSFORMATION; BETA-SI3N4; HARDNESS AB After polycrystalline silicon nitride samples with various alpha/beta phase ratios were fabricated by uniaxial hot-pressing under vacuum, their microstructures, alpha-to-beta transformations, and grain-growth mechanisms were then characterized by electron microscopy. Room-temperature fracture toughness (K-IC) increased with increasing beta-phase content, and a value of 7.0 +/- 0.5 MPa . m(1/2) was obtained for a sample that contained 60 vol % beta phase. The increase in K-IC is the result of an increase in elongated-grain fractions with increasing beta content, which promotes energy absorption by crack deflection, as well as by grain debonding, pullout, and bridging mechanisms. (C) 1998 Kluwer Academic Publishers C1 Argonne Natl Lab, Div Energy Technol, Argonne, IL 60439 USA. Univ Sevilla, Dept Fis Mat Condensada, Seville, Spain. RP De Arellano-Lopez, AR (reprint author), Argonne Natl Lab, Div Energy Technol, 9700 S Cass Ave, Argonne, IL 60439 USA. EM jp-singh@qmgate.anl.gov RI MARTINEZ FERNANDEZ, JULIAN/K-1826-2012 OI MARTINEZ FERNANDEZ, JULIAN/0000-0002-1199-6638 NR 27 TC 12 Z9 12 U1 1 U2 6 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0022-2461 J9 J MATER SCI JI J. Mater. Sci. PD DEC 15 PY 1998 VL 33 IS 24 BP 5803 EP 5810 PG 8 WC Materials Science, Multidisciplinary SC Materials Science GA 170YG UT WOS:000078834300010 ER PT J AU Yoo, BS Das, CR AF Yoo, BS Das, CR TI A fast and efficient processor management scheme for k-ary n-cubes SO JOURNAL OF PARALLEL AND DISTRIBUTED COMPUTING LA English DT Article ID HYPERCUBE COMPUTERS; ALLOCATION STRATEGY AB Job scheduling and processor allocation are two key components of processor management technique in a multiprocessor operating system. We propose a fast and efficient processor management technique, called virtual cube (VC), for k-ary n-cubes in this paper. The proposed scheme supports spatial allocation of jobs to the virtual cubes of the system and multiprograms the virtual cubes in a round-robin fashion. The objective here is to reduce job waiting lime and fragmentation. The VC scheme uses a fast sub-cube allocation algorithm called enhanced k-ary buddy. A novel approach, called paging, is proposed for fast submesh allocation. When used with the first fit algorithm, the paging scheme is shown to be extremely fast and efficient compared to other contemporary submesh allocation algorithms for k-ary n-cubes. We also study the impact of page size on performance and illustrate a methodology to compute optimal page size. Simulation results show that the VC scheme with its multiprogramming capability can boost system performance considerably and outperforms all existing policies while incurring minimal run-time overhead. (C) 1998 Academic Press. C1 Lawrence Livermore Natl Lab, Ctr Appl Sci Comp, Livermore, CA 94551 USA. Penn State Univ, Dept Comp Sci & Engn, University Pk, PA 16802 USA. RP Lawrence Livermore Natl Lab, Ctr Appl Sci Comp, POB 5508, Livermore, CA 94551 USA. NR 24 TC 2 Z9 2 U1 0 U2 0 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0743-7315 EI 1096-0848 J9 J PARALLEL DISTR COM JI J. Parallel Distrib. Comput. PD DEC 15 PY 1998 VL 55 IS 2 BP 192 EP 214 DI 10.1006/jpdc.1998.1498 PG 23 WC Computer Science, Theory & Methods SC Computer Science GA 159GC UT WOS:000078162900003 ER PT J AU Wang, JM Hartling, JA Flanagan, JM AF Wang, JM Hartling, JA Flanagan, JM TI Crystal structure determination of Escherichia coli ClpP starting from an EM-derived mask SO JOURNAL OF STRUCTURAL BIOLOGY LA English DT Article ID ATP-DEPENDENT PROTEASE; BACTERIAL CHAPERONIN GROEL; ANTIGENIC PEPTIDES; 20S PROTEASOME; RESOLUTION; HYDROLYSIS; PROTEINS; COMPLEX; HSLV; DEGRADATION AB Large ATP-dependent proteolytic complexes carry out the majority of intracellular proteolysis. To begin to understand the function of these proteases at a structural level, we have combined the information from a number of biophysical techniques such as electron microscopy (EM), small-angle scattering, and x-ray crystallography. In this study, we exploited the inherent symmetry of Escherichia coli ClpP, the proteolytic component of the ClpAP/XP ATP-dependent protease, to determine its x-ray crystal structure to 2.3-Angstrom resolution starting with a phase set derived from a low-resolution mask obtained from EM and small-angle x-ray scattering analysis. Sevenfold and 14-fold noncrystallographic symmetry averaging facilitated phase extension beyond 20 Angstrom and in combination with mask redetermination and matrix refinement was sufficient for completely determining the structure. The structure of ClpP is a homo-tetradecamer composed of two heptameric rings enclosing a cavity of similar to 50 Angstrom in diameter that compartmentalizes the 14 serine proteolytic active sites. Comparison of the ClpP structure with those of the 20S proteasome and HslV reveals a striking example of evolutionary convergence, despite them being unrelated in sequence and fold. Moreover, similarity in their overall architecture suggests a common model for their action. (C) 1998 Academic Press. C1 Yale Univ, Dept Mol Biophys & Biochem, New Haven, CT 06520 USA. Brookhaven Natl Lab, Dept Biol, Upton, NY 11973 USA. RP Wang, JM (reprint author), Yale Univ, Dept Mol Biophys & Biochem, New Haven, CT 06520 USA. EM flanagan@bnlbio.bio.bnl.gov FU NIGMS NIH HHS [GM-22778] NR 52 TC 39 Z9 40 U1 0 U2 2 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 1047-8477 J9 J STRUCT BIOL JI J. Struct. Biol. PD DEC 15 PY 1998 VL 124 IS 2-3 BP 151 EP 163 DI 10.1006/jsbi.1998.4058 PG 13 WC Biochemistry & Molecular Biology; Biophysics; Cell Biology SC Biochemistry & Molecular Biology; Biophysics; Cell Biology GA 176TC UT WOS:000079167000007 PM 10049803 ER PT J AU Bourke, MAM Rangaswamy, P Holden, TM Leachman, R AF Bourke, MAM Rangaswamy, P Holden, TM Leachman, R TI Complementary X-ray and neutron strain measurements of a carburized surface SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article DE carburization; diffraction; stress ID DIFFRACTION AB Lattice spacing profiles through a carburized layer in a cylindrical 5120 steel specimen were recorded using X-ray and neutron diffraction. The neutron measurements were performed non destructively, whereas the X-ray measurements employed sequential layer removal by electropolishing. The X-ray measurements provided a base determination of residual stress and microstructure, against which the neutron results were critically compared. Several methods were considered for determining the unstrained lattice parameter variation, necessary for interpretation of the neutron results. (C) 1998 Elsevier Science S.A. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. AECL Res, Chalk River Labs, Natl Res Council, Chalk River, ON K0J 1J0, Canada. Gen Motors Gear Ctr, Romulus, MI 48174 USA. RP Bourke, MAM (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 10 TC 13 Z9 14 U1 0 U2 1 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0921-5093 J9 MAT SCI ENG A-STRUCT JI Mater. Sci. Eng. A-Struct. Mater. Prop. Microstruct. Process. PD DEC 15 PY 1998 VL 257 IS 2 BP 333 EP 340 DI 10.1016/S0921-5093(98)00803-X PG 8 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 149ZC UT WOS:000077636200015 ER PT J AU Lin, JY Tallents, GJ Zhang, J MacPhee, AG Lewis, CLS Neely, D Nilsen, J Pert, GJ O'Rourke, RMN Smith, R Wolfrum, E AF Lin, JY Tallents, GJ Zhang, J MacPhee, AG Lewis, CLS Neely, D Nilsen, J Pert, GJ O'Rourke, RMN Smith, R Wolfrum, E TI Gain saturation of the Ni-like X-ray lasers SO OPTICS COMMUNICATIONS LA English DT Article ID XUV LASER; NM; OUTPUT; IONS; LINE AB Driven by a double 75 ps pulse with 2.2 ns separation, saturated operation of nickel-like Ag, In, Sn, and Sm X-ray lasers have been demonstrated with only 75 J drive energy on target. The variation of X-ray laser output with target length is found to fit well to a simple model for an amplified spontaneous emission (ASE) laser including saturation. Small signal gains of similar to 10 cm(-1), effective gain length products of similar to 18, and saturation irradiance of (1-5)x 10(10) W/cm(2) are measured for these lasers using a fitting procedure. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Univ Essex, Dept Phys, Colchester CO4 3SQ, Essex, England. Univ Oxford, Dept Phys, Clarendon Lab, Oxford OX1 3PU, England. Queens Univ Belfast, Sch Math & Phys, Belfast BT7 1NN, Antrim, North Ireland. Rutherford Appleton Lab, Cent Laser Facil, Didcot OX11 0QX, Oxon, England. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ York, Dept Phys, York YO1 5DD, N Yorkshire, England. RP Tallents, GJ (reprint author), Univ Essex, Dept Phys, Colchester CO4 3SQ, Essex, England. RI Zhang, Jie/O-8767-2014 NR 30 TC 36 Z9 37 U1 0 U2 8 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0030-4018 J9 OPT COMMUN JI Opt. Commun. PD DEC 15 PY 1998 VL 158 IS 1-6 BP 55 EP 60 DI 10.1016/S0030-4018(98)00577-X PG 6 WC Optics SC Optics GA 152AH UT WOS:000077752700011 ER PT J AU Powers, PE Aniolek, KW Kulp, TJ Richman, BA Bisson, SE AF Powers, PE Aniolek, KW Kulp, TJ Richman, BA Bisson, SE TI Periodically poled lithium niobate optical parametric amplifier seeded with the narrow-band filtered output of an optical parametric generator SO OPTICS LETTERS LA English DT Article ID PULSES AB The results of a simple scheme to generate continuously tunable pulsed narrow-bandwidth (less than 0.1 cm(-1)) light in the infrared are presented. A periodically poled lithium niobate (PPLN) optical parametric amplifier is seeded with the filtered output of a PPLN optical parametric generator. A high-finesse Fabry-Perot etalon is used as the filtering element, giving bandwidths as narrow as 0.08 cm(-1) and tunable over 18 cm(-1) without any adjustments to the PPLN crystals. High efficiency is obtained with a 15-ns 1-kHz Nd:YAG laser, giving energies of up to 180 mu J of signal at 1.6 mu m and 60 mu J of idler at 3.3 mu m. (C) 1998 Optical Society of America. C1 Univ Dayton, Dept Phys, Dayton, OH 45469 USA. Sandia Natl Labs, Combust Res Facil, Livermore, CA 94550 USA. RP Powers, PE (reprint author), Univ Dayton, Dept Phys, Dayton, OH 45469 USA. NR 10 TC 39 Z9 39 U1 3 U2 15 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0146-9592 J9 OPT LETT JI Opt. Lett. PD DEC 15 PY 1998 VL 23 IS 24 BP 1886 EP 1888 DI 10.1364/OL.23.001886 PG 3 WC Optics SC Optics GA 148JB UT WOS:000077500600006 PM 18091944 ER PT J AU Brower, R Chandrasekharan, S Wiese, UJ AF Brower, R Chandrasekharan, S Wiese, UJ TI Green's functions from quantum cluster algorithms SO PHYSICA A LA English DT Article DE quantum spins; clusters; Green's functions; improved estimators ID SIMULATIONS; DYNAMICS; MODELS AB We show that cluster algorithms for quantum models have a meaning independent of the basis chosen to construct them. Using this idea, we propose a new method for measuring with little effort a whole class of Green's functions, once a cluster algorithm for the partition function has been constructed. To explain the idea, we consider the quantum XY model and compute its two point Green's function in various ways, showing that all of them are equivalent. We also provide numerical evidence confirming the analytic arguments. Similar techniques are applicable to other models. In particular, in the recently constructed quantum link models, the new technique allows us to construct improved estimators for Wilson loops and may lead to a very precise determination of the glueball spectrum. (C) 1998 Published by Elsevier Science B.V. All rights reserved. C1 Boston Univ, Dept Phys, Boston, MA 02215 USA. MIT, Ctr Theoret Phys, Nucl Sci Lab, Cambridge, MA 02139 USA. MIT, Dept Phys, Cambridge, MA 02139 USA. Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Brower, R (reprint author), Boston Univ, Dept Phys, 590 Commonwealth Ave, Boston, MA 02215 USA. OI Chandrasekharan, Shailesh/0000-0002-3711-4998 NR 11 TC 22 Z9 22 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0378-4371 J9 PHYSICA A JI Physica A PD DEC 15 PY 1998 VL 261 IS 3-4 BP 520 EP 533 DI 10.1016/S0378-4371(98)00325-2 PG 14 WC Physics, Multidisciplinary SC Physics GA 152YR UT WOS:000077806100019 ER PT J AU Baer, R Head-Gordon, M AF Baer, R Head-Gordon, M TI Energy renormalization-group method for electronic structure of large systems SO PHYSICAL REVIEW B LA English DT Article ID BINDING MOLECULAR-DYNAMICS; DENSITY-FUNCTIONAL THEORY; SIZE SCALING METHODS; MATRIX METHOD; EIGENVALUES; ALGORITHM; NUMBER; MODEL AB A renormalization-group method for electronic structure of large systems within a tight-binding framework is presented. A telescopic series of nested Hilbert spaces is constructed, having exponentially decreasing dimensions and electrons. The Hamiltonian matrices have exponentially converging energy ranges focusing to the Fermi level. The computational effort scales near linearly with system size even when the density matrix is highly nonlocal. This is illustrated by calculations on a model metal and a metallic finite carbon nanotube, for which standard linear scaling methods are inapplicable. [S0163-1829(98)02644-7]. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA. RP Baer, R (reprint author), Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. NR 27 TC 20 Z9 20 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD DEC 15 PY 1998 VL 58 IS 23 BP 15296 EP 15299 DI 10.1103/PhysRevB.58.15296 PG 4 WC Physics, Condensed Matter SC Physics GA 148PY UT WOS:000077542100004 ER PT J AU Forrest, RL Golding, TD Moss, SC Zhang, Z Geisz, JF Olson, JM Mascarenhas, A Ernst, P Geng, C AF Forrest, RL Golding, TD Moss, SC Zhang, Z Geisz, JF Olson, JM Mascarenhas, A Ernst, P Geng, C TI X-ray diffraction and excitation photoluminescence analysis of ordered GaInP SO PHYSICAL REVIEW B LA English DT Article ID SEMICONDUCTOR ALLOYS; OPTICAL-PROPERTIES AB X-ray diffraction is shown to provide a direct, quantitative, structural measurement of the degree of spontaneous ordering in GaInP. In this paper we combine x-ray diffraction and excitation photoluminescence analyses of CuPt-ordered GaInP, and comparing the results to theoretical predictions for the dependence of the band structure on order parameter, determine the values of the band-gap reduction and crystal-field splitting parameters for the perfectly ordered alloy. [S0163-1829(98)06447-9]. C1 Univ Houston, Dept Phys, Houston, TX 77204 USA. Natl Renewable Energy Lab, Golden, CO 80401 USA. Univ Stuttgart, Inst Phys 4, D-70550 Stuttgart, Germany. RP Forrest, RL (reprint author), Univ Houston, Dept Phys, Houston, TX 77204 USA. EM Rforrest@uh.edu NR 15 TC 26 Z9 26 U1 0 U2 5 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD DEC 15 PY 1998 VL 58 IS 23 BP 15355 EP 15358 DI 10.1103/PhysRevB.58.15355 PG 4 WC Physics, Condensed Matter SC Physics GA 148PY UT WOS:000077542100020 ER PT J AU Wallace, DC AF Wallace, DC TI Electronic and phonon properties of six crystalline phases of Pu metal SO PHYSICAL REVIEW B LA English DT Article ID STRUCTURAL-PROPERTIES; PLUTONIUM; ELEMENTS AB In the light actinides Th to Np, and in the low-temperature alpha phase of Pu, the 5f electrons are itinerant, while in the five higher-temperature phases of Pu, and in the heavy actinides from Am on, the 5f electrons are localized to varying degrees. To understand the physics of 5f localization is a current problem in electronic-structure theory. The kind of experimental data that can help in solving this problem is not available. In this paper, thermodynamic data for Pu metal are analyzed to extract the quantities important for electronic-structure theory. For each of the six crystal phases, the following quantities are evaluated: (a) the static lattice potential, which is the ground-state energy of electronic-structure calculations, (b) central moments of the phonon distribution, which can be compared to any theoretical calculation of phonon frequencies, and (c) a measure of combined anharmonic and electronic excitation contributions to entropy, which contains information on the electronic density of states. Though at present we are not able to separate anharmonic and electronic excitation effects, the last named quantity will help to do so in the future. [S0163-1829(98)00448-2]. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 29 TC 54 Z9 55 U1 0 U2 3 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9950 EI 2469-9969 J9 PHYS REV B JI Phys. Rev. B PD DEC 15 PY 1998 VL 58 IS 23 BP 15433 EP 15439 DI 10.1103/PhysRevB.58.15433 PG 7 WC Physics, Condensed Matter SC Physics GA 148PY UT WOS:000077542100041 ER PT J AU Chase, SJ Mitch, MG Lannin, JS Olson, CG AF Chase, SJ Mitch, MG Lannin, JS Olson, CG TI Effects of disorder on alkali-doped C-60 photoemission and Raman spectra SO PHYSICAL REVIEW B LA English DT Article ID ELECTRONIC STATES; PHASES; FULLERIDES; SCATTERING; RBXC60; LEVEL; BAND AB Photoemission and Raman spectroscopy performed on alkali-doped C-60 has revealed the origin of an additional feature often seen between the conduction bands derived from the highest occupied molecular orbital and lowest unoccupied molecular orbital. Changes in these bands due to variation of temperature, stoichiometry, and alkali metal are correlated with the behavior of a disorder-induced intramolecular Raman-scattering peak. Loss of interstitial site symmetry due to thin-film disorder is suggested to be the origin of the additional electronic structure and associated Raman band. This would imply the effects of intermolecular interactions on the electronic properties of alkali-doped C-60 are still not completely understood. [S0163-1829(98)01048-0]. C1 Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Penn State Univ, Dept Phys, University Pk, PA 16802 USA. RP Chase, SJ (reprint author), Iowa State Univ, Ames Lab, Ames, IA 50011 USA. NR 23 TC 6 Z9 6 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD DEC 15 PY 1998 VL 58 IS 23 BP 15491 EP 15495 DI 10.1103/PhysRevB.58.15491 PG 5 WC Physics, Condensed Matter SC Physics GA 148PY UT WOS:000077542100047 ER PT J AU Sofo, JO Mahan, GD AF Sofo, JO Mahan, GD TI Electronic structure of CoSb3: A narrow-band-gap semiconductor SO PHYSICAL REVIEW B LA English DT Article ID LIGHTLY DOPED COSB3; FILLED SKUTTERUDITES; TRANSPORT-PROPERTIES; LATTICE-DYNAMICS; COAS3; COP3 AB We report calculations which show that the band structure of CoSb3 is typical of a narrow-band-gap semiconductor. The gap is strongly dependent on the relative position of the Sb atoms inside the unit cell. We obtain a band gap of 0.22 eV after minimization of these positions. This value is more than four times larger than the result of a previous calculation, which reported that the energy bands near the Fermi surface are unusual. The electronic states close to the Fermi level are properly described by a two-band Kane model. The calculated effective masses and band gap are in excellent agreement with Shubnikov-de Haas and Hall effect measurements. Recent measurements of the transport coefficients of this compound can be understood assuming it is a narrow-band-gap semiconductor, in agreement with our results. [S0163-1829(98)03647-9]. C1 Comis Nacl Energia Atom, Ctr Atom Bariloche, RA-8400 Bariloche, Rio Negro, Argentina. Comis Nacl Energia Atom, Inst Balseiro, RA-8400 Bariloche, Rio Negro, Argentina. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. RP Sofo, JO (reprint author), Comis Nacl Energia Atom, Ctr Atom Bariloche, RA-8400 Bariloche, Rio Negro, Argentina. EM sofo@cab.cnea.edu.ar RI Sofo, Jorge/J-4415-2012; Sofo, Jorge/B-4344-2014 OI Sofo, Jorge/0000-0003-4513-3694; Sofo, Jorge/0000-0003-4513-3694 NR 27 TC 120 Z9 123 U1 5 U2 31 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD DEC 15 PY 1998 VL 58 IS 23 BP 15620 EP 15623 DI 10.1103/PhysRevB.58.15620 PG 4 WC Physics, Condensed Matter SC Physics GA 148PY UT WOS:000077542100062 ER PT J AU Marinescu, DC Quinn, JJ AF Marinescu, DC Quinn, JJ TI Long-wavelength collective excitations in a two-dimensional spin-polarized electron gas: A phenomenological theory SO PHYSICAL REVIEW B LA English DT Article AB The dispersion relations of the collective excitations induced in a 2D spin-polarized electron gas are derived within the framework of the Landau-Silin theory applied to a two-component Fermi liquid. The quasiparticle interaction is described by spin-dependent coefficients, which are parametric functions of the initial degree of polarization. The motion of the low-energy excitations satisfies a semiclassical transport equation solved consistently with the Maxwell equations for the electromagnetic field produced by spin and charge fluctuations. The long-wavelength limit of the self-sustained oscillations is analyzed as a function of the initial degree of polarization of the system, preset by a de magnetic induction. [S0163-1829(98)01548-3]. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Univ Tennessee, Dept Phys, Knoxville, TN 37906 USA. RP Marinescu, DC (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. NR 17 TC 4 Z9 4 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD DEC 15 PY 1998 VL 58 IS 23 BP 15688 EP 15697 DI 10.1103/PhysRevB.58.15688 PG 10 WC Physics, Condensed Matter SC Physics GA 148PY UT WOS:000077542100071 ER PT J AU Berera, A Gleiser, M Ramos, RO AF Berera, A Gleiser, M Ramos, RO TI Strong dissipative behavior in quantum field theory SO PHYSICAL REVIEW D LA English DT Article ID ELECTROWEAK PHASE-TRANSITION; FINITE-TEMPERATURE; EARLY UNIVERSE; SCALAR FIELD; EVOLUTION EQUATION; HIGGS FIELD; SUBCRITICAL BUBBLES; THERMAL-EQUILIBRIUM; EXPANDING UNIVERSE; REAL-TIME AB We study the conditions under which an overdamped regime can be attained in the dynamic evolution of a quantum field configuration. Using a real-time formulation of finite temperature field theory, we compute the effective evolution equation of a scalar field configuration, quadratically interacting with a given set of other scalar fields. We then show that, in the overdamped regime, the dissipative kernel in the field equation of motion is closely related to the shear viscosity coefficient, as computed in scalar field theory at finite temperature. The effective dynamics is equivalent to a time-dependent Ginzburg-Landau description of the approach to equilibrium in phenomenological theories of phase transitions. Applications of our results, including a recently proposed inflationary scenario called "warm inflation," are discussed. [S0556-2821(98)03474-5]. C1 Vanderbilt Univ, Dept Phys & Astron, Nashville, TN 37235 USA. Dartmouth Coll, Dept Phys & Astron, Hanover, NH 03755 USA. NASA, Fermilab Astrophys Ctr, Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. Osservatorio Astron Roma, I-00136 Rome, Italy. Univ Estado Rio de Janeiro, Inst Fis, Dept Fis Teor, BR-20550013 Rio De Janeiro, Brazil. RP Berera, A (reprint author), Vanderbilt Univ, Dept Phys & Astron, Nashville, TN 37235 USA. EM berera@vuhep.phy.vanderbilt.edu; gleiser@peterpan.dartmouth.edu; rudnei@symbcomp.uerj.br RI Ramos, Rudnei/C-4492-2008 OI Ramos, Rudnei/0000-0001-8781-4928 NR 61 TC 140 Z9 141 U1 0 U2 3 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD DEC 15 PY 1998 VL 58 IS 12 AR 123508 DI 10.1103/PhysRevD.58.123508 PG 20 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 154RR UT WOS:000077903000019 ER PT J AU Boyanovsky, D de Vega, HJ Holman, R Kumar, SP Pisarski, RD AF Boyanovsky, D de Vega, HJ Holman, R Kumar, SP Pisarski, RD TI Real-time relaxation and kinetics in hot scalar QED: Landau damping SO PHYSICAL REVIEW D LA English DT Review ID QUARK-GLUON PLASMA; HARD THERMAL LOOPS; ENERGY NUCLEAR COLLISIONS; QUANTUM BROWNIAN-MOTION; ABELIAN GAUGE-THEORIES; FINITE-TEMPERATURE; FIELD-THEORY; TRANSPORT-THEORY; EARLY UNIVERSE; PARTICLE-PRODUCTION AB The real time evolution of non-equilibrium expectation values with soft length scales similar to k(-1)>(eT)(-1) is solved in hot scalar electrodynamics, with a view towards understanding relaxational phenomena in the QGP and the electroweak plasma. We find that the gauge invariant non-equilibrium expectation values relax via power laws to asymptotic amplitudes that are determined by the quasiparticle poles. The long time relaxational dynamics and relevant time scales are determined by the behavior of the retarded self-energy not at the small frequencies, but at the Landau damping thresholds. This explains the presence of power laws and not of exponential decay. In the process we rederive the Hn, effective action using non-equilibrium field theory. Furthermore we obtain the influence functional, the Langevin equation and the fluctuation-dissipation theorem for the soft modes, identifying the correlators that emerge in the classical limit. We show that a Markovian approximation fails to describe the dynamics both at short and long times. We find that the distribution function for soft quasiparticles relaxes with a power law through Landau damping. We also introduce a novel kinetic approach that goes beyond the standard Boltzmann equation by incorporating off-shell processes and find that the distribution function for soft quasiparticles relaxes with a power law through Landau damping. We find an unusual dressing dynamics of bare particles and anomalous (logarithmic) relaxation of hard quasiparticles. [S0556-2821(98)03722-9]. C1 Univ Pittsburgh, Dept Phys & Astron, Pittsburgh, PA 15260 USA. Univ Paris 06, LPTHE, F-75252 Paris 05, France. Univ Paris 07, F-75252 Paris 05, France. Carnegie Mellon Univ, Dept Phys, Pittsburgh, PA 15213 USA. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Boyanovsky, D (reprint author), Univ Pittsburgh, Dept Phys & Astron, Pittsburgh, PA 15260 USA. NR 118 TC 33 Z9 34 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD DEC 15 PY 1998 VL 58 IS 12 AR 125009 DI 10.1103/PhysRevD.58.125009 PG 25 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 154RR UT WOS:000077903000059 ER PT J AU Gaillard, MK Lyth, DH Murayama, H AF Gaillard, MK Lyth, DH Murayama, H TI Inflation and flat directions in modular invariant superstring effective theories SO PHYSICAL REVIEW D LA English DT Article ID DYNAMICAL SUPERSYMMETRY BREAKING; GAUGINO CONDENSATION; STRING THEORY; THERMAL INFLATION; TARGET SPACE; DUALITY; COUPLINGS; BARYOGENESIS; SUPERGRAVITY; COMPACTIFICATIONS AB The potential during inflation must be very fiat in, at least, the direction of the inflaton. In renormalizable global supersymmetry, flat directions are ubiquitous, but they are not preserved in a generic supergravity theory. It is known that at least some of them are preserved in no-scale supergravity, and simple generalizations of it. We here study a more realistic generalization, based on string-derived supergravity, using the linear supermultiplet formalism for the dilaton. We consider a general class of hybrid inflation models, where a Fayet-Illiopoulos D term drives some fields to large values. The potential is dominated by the F term, but flatness is preserved in some directions. This allows inflation, with the dilaton stabilized in its domain of attraction, and some moduli stabilized at their vacuum values. Another modulus may be the inflaton. [S0556-2821(98)04024-7]. C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Theoret Phys Grp, Berkeley, CA 94720 USA. Univ Lancaster, Dept Phys, Lancaster LA1 4YB, England. RP Gaillard, MK (reprint author), Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. RI Murayama, Hitoshi/A-4286-2011 NR 46 TC 38 Z9 38 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD DEC 15 PY 1998 VL 58 IS 12 AR 123505 DI 10.1103/PhysRevD.58.123505 PG 10 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 154RR UT WOS:000077903000016 ER PT J AU Kallosh, R Rajaraman, A AF Kallosh, R Rajaraman, A TI Vacua of M theory and string theory SO PHYSICAL REVIEW D LA English DT Article ID 11-DIMENSIONAL SUPERGRAVITY; P-BRANES; SUPERSYMMETRY; SUPERSPACE AB We argue that supersymmetric higher-dimension operators in the effective actions of M theory and type IIB suing theory do not affect the maximally supersymmetric vacua: AdS(4)XS(7) and AdS(7)XS(4) in M theory and AdS(5)xS(5) in type IIB string theory. All these vacua are described in superspace by a fixed point with all components of supertorsion and supercurvature being supercovariantly constant. This follows from 32 unbroken supersymmetries and allows us to prove that such vacua are exact. [S0556-2821(98)10520-9]. C1 Stanford Univ, Dept Phys, Stanford, CA 94305 USA. Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Kallosh, R (reprint author), Stanford Univ, Dept Phys, Stanford, CA 94305 USA. EM kallosh@physics.stanford.edu; arvindra@leland.stanford.edu NR 25 TC 70 Z9 70 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD DEC 15 PY 1998 VL 58 IS 12 AR 125003 DI 10.1103/PhysRevD.58.125003 PG 7 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 154RR UT WOS:000077903000053 ER PT J AU Kinney, WH AF Kinney, WH TI Constraining inflation with cosmic microwave background polarization SO PHYSICAL REVIEW D LA English DT Article ID COSMOLOGICAL PARAMETERS; ANISOTROPY EXPERIMENTS; DENSITY PERTURBATIONS; TENSOR PERTURBATIONS; SYMMETRY-BREAKING; UNIVERSE SCENARIO; MODELS; SCALE; SPECTRUM; RADIATION AB Observations of the polarization of the cosmic microwave backround (CMB) have the potential to place much tighter constraints on cosmological parameters than observations of the fluctuations in temperature alone. We discuss using CMB polarization to constrain parameters relevant for distinguishing among popular models for cosmological inflation, using the MAP and Planck satellite missions as example cases. Of particular interest is the ability to detect tiny contributions to the CMB anisotropy from tensor modes, which is fundamentally limited by cosmic variance in temperature-only observations. The ability to detect a tensor/scalar ratio r similar to 0.01 would allow precision tests of interesting inflation models, and is possible with a modest increase in sensitivity over that planned for the Planck satellite or is potentially achievable by ground-based experiments. [S0556-2821(98)01822-0]. C1 NASA, Fermilab Astrophys Ctr, Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. RP Kinney, WH (reprint author), NASA, Fermilab Astrophys Ctr, Fermi Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. EM kinneyw@fnal.gov NR 60 TC 81 Z9 81 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD DEC 15 PY 1998 VL 58 IS 12 AR 123506 DI 10.1103/PhysRevD.58.123506 PG 10 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 154RR UT WOS:000077903000017 ER PT J AU Kluger, Y Mottola, E Eisenberg, JM AF Kluger, Y Mottola, E Eisenberg, JM TI Quantum Vlasov equation and its Markov limit SO PHYSICAL REVIEW D LA English DT Article ID QUARK-GLUON PLASMA; PHASE-SPACE STRUCTURE; SCALAR FIELD-THEORIES; STRONG ELECTRIC-FIELD; HEAVY-ION COLLISIONS; FLUX-TUBE MODEL; PAIR PRODUCTION; PARTICLE-PRODUCTION; VACUUM; CREATION AB The adiabatic particle number in mean field theory obeys a quantum Vlasov equation which is nonlocal in time. For weak, slowly varying electric fields this particle number can be identified with the single particle distribution function in phase space, and its time rate of change is the appropriate effective source term for the Boltzmann-Vlasov equation. By analyzing the evolution of the particle number we exhibit the time structure of the particle creation process in a constant electric field, and derive the local form of the source term due to pair creation. In order to capture the secular Schwinger creation rare, the source term requires an asymptotic expansion which is uniform in time, and whose longitudinal momentum dependence can be approximated by a delta function only on time scales much longer than root p(perpendicular to)(2)+m(2)c(2)/eE. The local Vlasov source term amounts to a kind of Markov limit of field theory, where information about quantum phase correlations: in the created pairs is ignored and a reversible Hamiltonian evolution is replaced by an irreversible kinetic one. This replacement has a precise counterpart in the density matrix description, where it corresponds to disregarding the rapidly varying off-diagonal terms in the adiabatic number basis and treating the more slowly varying diagonal elements as the probabilities of creating pairs in a stochastic process. A numerical comparison between the quantum and local kinetic approaches to the dynamical back reaction problem shows remarkably good agreement, even in quite strong electric fields. eE similar or equal to m(2)c(3)/(h) over bar, over a large range of times. [S0556-2821(98)04520-2]. C1 Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Tel Aviv Univ, Raymond & Beverly Sackler Fac Exact Sci, Sch Phys & Astron, IL-69978 Tel Aviv, Israel. RP Kluger, Y (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, MS B285, Los Alamos, NM 87545 USA. NR 75 TC 110 Z9 111 U1 0 U2 4 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD DEC 15 PY 1998 VL 58 IS 12 AR 125015 DI 10.1103/PhysRevD.58.125015 PG 28 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 154RR UT WOS:000077903000065 ER PT J AU Moroi, T AF Moroi, T TI Cosmological moduli problem in a supersymmetric model with direct gauge mediation SO PHYSICAL REVIEW D LA English DT Article ID LOW-ENERGY SUPERSYMMETRY; EARLY-UNIVERSE; DARK-MATTER; BREAKING; AXIONS; INFLATION; SN-1987A; LIGHT; NUCLEOSYNTHESIS; CONSTRAINTS AB Recently, an interesting class of direct gauge mediation supersymmetry (SUSY) breaking models were proposed, in which the minimum of the potential of the SUSY breaking field was determined by the inverted hierarchy mechanism. We consider their cosmological implications. In this class of models, the SUSY breaking field has a very flat potential, which may have cosmological importance. Assuming the initial amplitude of the SUSY breaking field to be of the order of the Planck scale, it can be a source of large entropy production. Special attention is paid to the cosmological moduli problem, and we will see that the cosmological mass density of the moduli field can be significantly reduced. [S0556-2821(98)00324-5]. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Theoret Phys Grp, Berkeley, CA 94720 USA. RP Moroi, T (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Theoret Phys Grp, Berkeley, CA 94720 USA. NR 59 TC 4 Z9 4 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1550-7998 EI 1550-2368 J9 PHYS REV D JI Phys. Rev. D PD DEC 15 PY 1998 VL 58 IS 12 AR 124008 PG 19 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 154RR UT WOS:000077903000027 ER PT J AU Tran, PH Korszun, ZR Cerritelli, S Springhorn, SS Lacks, SA AF Tran, PH Korszun, ZR Cerritelli, S Springhorn, SS Lacks, SA TI Crystal structure of the DpnM DNA adenine methyltransferase from the DpnII restriction system of Streptococcus pneumoniae bound to S-adenosylmethionine SO STRUCTURE WITH FOLDING & DESIGN LA English DT Article DE adenine N6 methylation; DNA base eversion; methyltransferase evolution; multiwavelength anomalous diffraction; protein fold conservation ID ADENOSYL-L-METHIONINE; ESCHERICHIA-COLI; DIFFRACTION DATA; NUCLEOTIDE-SEQUENCE; METHYLASE GENE; PHAGE-T4 DAM; PROTEIN; MECHANISM; CLONING; BASE AB Background: Methyltransferases (Mtases) catalyze the transfer of methyl groups from S-adenosylmethionine (AdoMet) to a variety of small molecular and macromolecular substrates. These enzymes contain a characteristic alpha/beta structural fold. Four groups of DNA Mtases have been defined and representative structures have been determined for three groups. DpnM is a DNA Mtase that acts on adenine N6 in the sequence GATC; the enzyme represents group alpha DNA Mtases, for which no structures are known. Results: The structure of DpnM in complex with AdoMet was determined at 1.80 Angstrom resolution. The protein comprises a consensus Mtase fold with a helical cluster insert. DpnM binds AdoMet in a similar manner to most other Mtases and the enzyme contains a hollow that can accommodate DNA. The helical cluster supports a shelf within the hollow that may recognize the target sequence. Modeling studies indicate a potential site for binding the target adenine, everted from the DNA helix. Comparison of the DpnM structure and sequences of group alpha DNA Mtases indicates that the group is a genetically related family. Structural comparisons show DpnM to be most similar to a small-molecule Mtase and then to macromolecular Mtases, although several dehydrogenases show greater similarity than one DNA Mtase. Conclusions: DpnM, and by extension the DpnM family or group a Mtases, contains the consensus fold and AdoMet-binding motifs found in most Mtases. Structural considerations suggest that macromolecular Mtases evolved from small-molecule Mtases, with different groups of DNA Mtases evolving independently. Mtases may have evolved from dehydrogenases. Comparison of these enzymes indicates that in protein evolution, the structural fold is most highly conserved, then function and lastly sequence. C1 Brookhaven Natl Lab, Dept Biol, Upton, NY 11973 USA. RP Lacks, SA (reprint author), Brookhaven Natl Lab, Dept Biol, Upton, NY 11973 USA. EM lacks@sun2.bnl.gov FU NIGMS NIH HHS [GM29721] NR 65 TC 75 Z9 77 U1 2 U2 6 PU CURRENT BIOLOGY LTD PI LONDON PA 84 THEOBALDS RD, LONDON WC1X 8RR, ENGLAND SN 0969-2126 J9 STRUCT FOLD DES JI Struct. Fold. Des. PD DEC 15 PY 1998 VL 6 IS 12 BP 1563 EP 1575 DI 10.1016/S0969-2126(98)00154-3 PG 13 WC Biochemistry & Molecular Biology; Biophysics; Cell Biology SC Biochemistry & Molecular Biology; Biophysics; Cell Biology GA 152ND UT WOS:000077782900008 PM 9862809 ER PT J AU Ksiezak-Reding, H Yang, GZ Simon, M Wall, JS AF Ksiezak-Reding, H Yang, GZ Simon, M Wall, JS TI Assembled tau filaments differ from native paired helical filaments as determined by scanning transmission electron microscopy (STEM) SO BRAIN RESEARCH LA English DT Article DE ultrastructure; assembled tau filaments; paired helical filaments; scanning transmission electron microscopy; mass density; neurodegenerative disorders ID PROGRESSIVE SUPRANUCLEAR PALSY; HEPARAN-SULFATE PROTEOGLYCAN; ALZHEIMER-LIKE FILAMENTS; ATOMIC-FORCE MICROSCOPY; PROTEIN-TAU; CORTICOBASAL DEGENERATION; NEUROFIBRILLARY TANGLES; IN-VITRO; CYTOSKELETAL PATHOLOGY; HUMAN-BRAIN AB Paired helical filaments (PHF) are abnormal, approximately 20-25-nm wide periodically twisted filaments, which accumulate in Alzheimer's disease (PLD) brain and other neurodegenerative disorders, including corticobasal degeneration (CBD). PHF are primarily composed of highly phosphorylated tau protein. However, both phosphorylated and non-phosphorylated forms of tau are able to assemble in vitro into filaments similar in the ultrastructural appearance to PI-IF. In the present study, filaments were assembled in vitro from unmodified recombinant human tau and the physical mass per unit length of filaments and the mass density were determined using scanning transmission electron microscopy (STEM). Two general types of filaments were observed. One type was composed of 11.4 nm-wide, 10-75 nm long, frequently twisted and PHF-like filaments, with a mass per unit length (44 kDa/nm) approximately one third of that observed in isolated AD filaments. The other were straight filaments, approximately 6.8-nm wide and 0.2-2 mu m long, which often formed parallel clusters of two or more filaments. Triple clusters were 19.2-nm wide and had a mass per unit length (70 kDa/nm) approximately two thirds of that seen in isolated AD filaments. Despite different morphology, both twisted and straight filaments had mass densities between 0.48-0.55 kDa/nm(3). These values are significantly higher than those reported for PHF found either in AD (0.40 kDa/nm(3)) or CBD (0.33 kDa/nm(3)). These results suggest that the packing of tau differs in vivo from that observed in vitro and that specific tau isoform content, elongation of tau molecules by phosphorylation or other factors may be required to reproduce pathological assembly. Therefore mass density determinations appear to be an important criterion in comparing various filaments. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Albert Einstein Coll Med, Dept Pathol, Bronx, NY 10461 USA. Brookhaven Natl Lab, Dept Biol, Upton, NY 11973 USA. RP Ksiezak-Reding, H (reprint author), Albert Einstein Coll Med, Dept Pathol, 1300 Morris Pk Ave, Bronx, NY 10461 USA. EM reding@aecom.yu.edu FU NCRR NIH HHS [RR 01777]; NINDS NIH HHS [NS35254] NR 59 TC 9 Z9 9 U1 1 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0006-8993 J9 BRAIN RES JI Brain Res. PD DEC 14 PY 1998 VL 814 IS 1-2 BP 86 EP 98 DI 10.1016/S0006-8993(98)01052-X PG 13 WC Neurosciences SC Neurosciences & Neurology GA 153TT UT WOS:000077849300009 PM 9838058 ER PT J AU de Brouckere, G Feller, D AF de Brouckere, G Feller, D TI Configuration interaction calculations on the A(2)Pi(i) state of CP and the A(2)Pi(i)-X-2 Sigma(+) transition bands. Miscellaneous properties SO JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS LA English DT Article ID CORRELATED MOLECULAR CALCULATIONS; POTENTIAL-ENERGY CURVES; GAUSSIAN-BASIS SETS; SPECTROSCOPIC PROPERTIES; GROUND-STATE; WAVE-FUNCTIONS; EXCITED-STATES; P-2 MOLECULE; PN MOLECULE; WATER DIMER AB The first extended basis set configuration interaction and coupled cluster calculations have been performed on the lowest excited state (A (2)Pi(i)) of CP. A wide variety of molecular properties are reported, including: (i) spectroscopic constants; (ii) (2)Pi(i) vibrational energies and vibrational excitation energies; (iii) A (2)Pi(i)-X (2)Sigma(+) vibrational transition energies corresponding to several vibrational bands and related Franck-Condon factors; (iv) (2)Pi(i) pure rotational transitions for several (j', j ") values; (v) one-electron properties; (vi) vibrational electric dipole moments mu(upsilon) and (vii) (2)Pi(i) vibrational and rovibrational lifetimes. For several of the spectroscopic properties it was possible to estimate the complete basis set limit and to include limited core/valence correlation recovery. In general, good agreement was obtained with the limited amount of experimental data that was available. Whenever possible, comparison is made to the corresponding ground state (X (2)Sigma(+)) properties and to ground and excited states of closely related diatomics. Finally, the accuracy of the present results are discussed. C1 Univ Amsterdam, Dept Math Comp Sci Phys & Astron, NL-1018 XE Amsterdam, Netherlands. Pacific NW Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP de Brouckere, G (reprint author), Univ Amsterdam, Dept Math Comp Sci Phys & Astron, Valckenierstr 65, NL-1018 XE Amsterdam, Netherlands. NR 61 TC 8 Z9 8 U1 0 U2 3 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0953-4075 J9 J PHYS B-AT MOL OPT JI J. Phys. B-At. Mol. Opt. Phys. PD DEC 14 PY 1998 VL 31 IS 23 BP 5053 EP 5075 PG 23 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 151MJ UT WOS:000077723700005 ER PT J AU Brauning, H Dorner, R Cocke, CL Krassig, B Kheifets, AS Bray, I Brauning-Demain, A Carnes, K Dreuil, S Mergel, V Richard, P Ullrich, J Schmidt-Bocking, H AF Brauning, H Dorner, R Cocke, CL Krassig, B Kheifets, AS Bray, I Brauning-Demain, A Carnes, K Dreuil, S Mergel, V Richard, P Ullrich, J Schmidt-Bocking, H TI Absolute triple differential cross sections for photo-double ionization of helium - experiment and theory SO JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS LA English DT Article ID ELECTRON-HYDROGEN SCATTERING; EV ABOVE-THRESHOLD; DOUBLE PHOTOIONIZATION; ANGULAR-DISTRIBUTIONS; RECOIL-ION; SINGLE IONIZATION; ENERGY ELECTRONS; NEAR-THRESHOLD; DYNAMICS; ASYMMETRY AB We have measured absolute triple differential cross sections for photo-double ionization of helium at 20 eV excess. The measurement covers the full ranges of energy sharing and emission angles of the two photoelectrons. We compare our data for selected geometries with the convergent close-coupling (CCC) calculations as well as 2SC calculations by Pont and Shakeshaft and 3C calculations by Maulbetsch and Briggs. In terms of the absolute magnitude and the trend in the shapes of the triple differential cross section for different geometries we find good agreement of the CCC and published 2SC calculations with our measurement, though differences with respect to the observed shape of individual patterns still exist. C1 Kansas State Univ, Dept Phys, Manhattan, KS 66506 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Frankfurt, Inst Kernphys, D-60486 Frankfurt, Germany. Argonne Natl Lab, Argonne, IL 60439 USA. Univ Freiburg, D-79104 Freiburg, Germany. Australian Natl Univ, Canberra, ACT 0200, Australia. Flinders Univ S Australia, Adelaide, SA 5001, Australia. RP Brauning, H (reprint author), Kansas State Univ, Dept Phys, Cardwell Hall, Manhattan, KS 66506 USA. RI Kheifets, Anatoli/C-9131-2009; Bray, Igor/B-8586-2009; Doerner, Reinhard/A-5340-2008 OI Kheifets, Anatoli/0000-0001-8318-9408; Bray, Igor/0000-0001-7554-8044; Doerner, Reinhard/0000-0002-3728-4268 NR 39 TC 105 Z9 106 U1 0 U2 3 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0953-4075 J9 J PHYS B-AT MOL OPT JI J. Phys. B-At. Mol. Opt. Phys. PD DEC 14 PY 1998 VL 31 IS 23 BP 5149 EP 5160 DI 10.1088/0953-4075/31/23/012 PG 12 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 151MJ UT WOS:000077723700012 ER PT J AU Weir, ST AF Weir, ST TI Metallization of fluid hydrogen by multiple shock compression SO JOURNAL OF PHYSICS-CONDENSED MATTER LA English DT Article; Proceedings Paper CT Oji International Seminar on the Quest for New Physical Phases under Extreme Conditions CY MAY 31-JUN 05, 1998 CL TOMAKOMAI, JAPAN ID ELECTRICAL-CONDUCTIVITY; MOLECULAR-HYDROGEN; MEGABAR PRESSURES; HIGH-DENSITY AB The electrical conductivity of fluid, molecular hydrogen is studied to a density of 0.38 mol cm(-3), which is about a tenfold compression from the initial, ambient-pressure, liquid hydrogen state. The hydrogen was compressed by means of a reverberating shock wave. By compressing the hydrogen with a rapid series of relatively weak shock waves instead of a single strong shock wave, we minimize the heating of the sample and achieve very high densities. Calculated densities were in the range 0.29-0.38 mol cm(-3), and calculated temperatures were in the range 1600-3100 K. The data indicate that hydrogen undergoes a continuous transition from a fluid, molecular semiconductor to a fluid, molecular metal at a pressure of 1.4 Mbars and a calculated temperature of 2600 K. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Weir, ST (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808, Livermore, CA 94550 USA. RI Weir, Samuel/H-5046-2012 NR 13 TC 3 Z9 3 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0953-8984 J9 J PHYS-CONDENS MAT JI J. Phys.-Condes. Matter PD DEC 14 PY 1998 VL 10 IS 49 BP 11147 EP 11156 DI 10.1088/0953-8984/10/49/005 PG 10 WC Physics, Condensed Matter SC Physics GA 151MG UT WOS:000077723500004 ER PT J AU Oomi, G Kagayama, T Honda, F Honda, K Mori, N Canfield, PC Sechovsky, V Andreev, AV AF Oomi, G Kagayama, T Honda, F Honda, K Mori, N Canfield, PC Sechovsky, V Andreev, AV TI Highly correlated electron systems under multi-extreme conditions SO JOURNAL OF PHYSICS-CONDENSED MATTER LA English DT Article; Proceedings Paper CT Oji International Seminar on the Quest for New Physical Phases under Extreme Conditions CY MAY 31-JUN 05, 1998 CL TOMAKOMAI, JAPAN ID HIGH-PRESSURE; LOW-TEMPERATURES; UNIGA; STATE; CEAL3 AB Electrical and magnetic properties of highly correlated electron systems are investigated under multi-extreme conditions: high pressure, low temperature and high magnetic fields. The instability of the electronic state under multi-extreme conditions is systematically discussed on the basis of the data obtained. It is suggested that one kind of interaction is enhanced but another is suppressed under multi-extreme conditions, which gives rise to a lot of interesting electronic transitions. C1 Kumamoto Univ, Dept Mech Engn & Mat Sci, Kumamoto 8608555, Japan. Kumamoto Natl Coll Technol, Kumamoto 8611102, Japan. Univ Tokyo, Inst Solid State Phys, Minato Ku, Tokyo 1068666, Japan. Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Charles Univ, Dept Met Phys, CR-12116 Prague 2, Czech Republic. Acad Sci Czech Republ, Inst Met Phys, Prague 18040 8, Czech Republic. RP Oomi, G (reprint author), Kumamoto Univ, Dept Mech Engn & Mat Sci, Kumamoto 8608555, Japan. RI Andreev, Alexander/B-6057-2011; Canfield, Paul/H-2698-2014; HONDA, Fuminori/D-5578-2015; Sechovsky, Vladimir/A-5256-2008 OI HONDA, Fuminori/0000-0002-9485-7384; Sechovsky, Vladimir/0000-0003-1298-2120 NR 15 TC 0 Z9 0 U1 0 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0953-8984 J9 J PHYS-CONDENS MAT JI J. Phys.-Condes. Matter PD DEC 14 PY 1998 VL 10 IS 49 BP 11531 EP 11536 DI 10.1088/0953-8984/10/49/039 PG 6 WC Physics, Condensed Matter SC Physics GA 151MG UT WOS:000077723500038 ER PT J AU Abe, F Akimoto, H Akopian, A Albrow, MG Amadon, A Amendolia, SR Amidei, D Antos, J Aota, S Apollinari, G Arisawa, T Asakawa, T Ashmanskas, W Atac, M Azzi-Bacchetta, P Bacchetta, N Bagdasarov, S Bailey, MW de Barbaro, P Barbaro-Galtieri, A Barnes, VE Barnett, BA Barone, M Bauer, G Baumann, T Bedeschi, F Behrends, S Belforte, S Bellettini, G Bellinger, J Benjamin, D Bensinger, J Beretvas, A Berge, JP Berryhill, J Bertolucci, S Bettelli, S Bevensee, B Bhatti, A Biery, K Bigongiari, C Binkley, M Bisello, D Blair, RE Blocker, C Blusk, S Bodek, A Bokhari, W Bolla, G Bonushkin, Y Bortoletto, D Boudreau, J Breccia, L Bromberg, C Bruner, N Brunetti, R Buckley-Geer, E Budd, HS Burkett, K Busetto, G Byon-Wagner, A Byrum, KL Campbell, M Caner, A Carithers, W Carlsmith, D Cassada, J Castro, A Cauz, D Cerri, A Chang, PS Chang, PT Chao, HY Chapman, J Cheng, MT Chertok, M Chiarelli, G Chiou, CN Chlebana, F Christofek, L Chu, ML Cihangir, S Clark, AG Cobal, M Cocca, E Contreras, M Convery, ME Conway, J Cooper, J Cordelli, M Costanzo, D Couyoumtzelis, C Cronin-Hennessy, D Culbertson, R Dagenhart, D Daniels, T DeJongh, F Dell'Agnello, S Dell'Orso, M Demina, R Demortier, L Deninno, M Derwent, PF Devlin, T Dittmann, JR Donati, S Done, J Dorigo, T Eddy, N Einsweiler, K Elias, JE Ely, R Engels, E Erdmann, W Errede, W Errede, S Fan, Q Feild, RG Feng, Z Ferretti, C Fiori, I Flaugher, B Foster, GW Franklin, M Freeman, J Friedman, J Frisch, H Fukui, Y Gadomski, S Galeotti, S Gallinaro, M Ganel, O Garcia-Sciveres, M Garfinkel, AF Gay, C Geer, S Gerdes, DW Giannetti, P Giokaris, N Giusti, G Gold, M Gordon, A Goshaw, AT Gotra, Y Goulianos, K Grassmann, H Groer, L Grosso-Pilcher, C Guillian, G da Costa, JG Guo, RS Haber, C Hafen, E Hahn, SR Hamilton, R Handa, T Handler, R Happacher, F Hara, K Hardman, AD Harris, RM Hartmann, F Hauser, J Hayashi, E Heinrich, J Hao, W Hinrichsen, B Hoffman, KD Hohlmann, M Holck, C Hollebeek, R Holloway, L Huang, Z Huffman, BT Hughes, R Huston, J Huth, J Ikeda, H Incagli, M Incandela, J Introzzi, G Iwai, J Iwata, Y James, E Jensen, H Joshi, U Kajfasz, E Kambara, H Kamon, T Kaneko, T Karr, K Kasha, H Kato, Y Keaffaber, TA Kelley, K Kennedy, RD Kephart, R Kestenbaum, D Khazins, D Kikuchi, T Kim, BJ Kim, HS Kim, SH Kim, YK Kirsch, L Klimenko, S Knoblauch, D Koehn, P Kongeter, A Kondo, K Konigsberg, J Kordas, K Korytov, A Kovacs, E Kowald, W Kroll, J Kruse, M Kuhlmann, SE Kuns, E Kurino, K Kuwabara, T Laasanen, AT Lami, S Lammel, S Lamoureux, JI Lancaster, M Lanzoni, M Latino, G LeCompte, T Leone, S Lewis, JD Lindgren, M Liss, TM Liu, JB Liu, YC Lockyer, N Long, O Loomis, C Loreti, M Lucchesi, D Lukens, P Lusin, S Lys, J Maeshima, K Maksimovic, P Mangano, M Mariotti, M Marriner, JP Martignon, G Martin, A Matthews, JAJ Mazzanti, P McFarland, K McIntrye, P Melese, P Menguzzato, M Menzione, A Meschi, E Mesropian, C Metzler, S Miao, C Miao, T Michail, G Miller, R Minato, H Miscetti, S Mishina, M Miyashita, S Moggi, N Moore, E Morita, Y Mukherjee, A Muller, T Murat, P Murgia, S Musy, M Nakada, H Nakaya, T Nakano, I Nelson, C Neuberger, D Newman-Holmes, C Ngan, CYP Nodulman, L Nomerotski, A Oh, SH Ohmoto, T Ohsugi, T Oishi, R Okabe, M Okusawa, T Olsen, J Pagliarone, C Paoletti, R Papadimitriou, V Pappas, SP Parashar, N Parri, A Patrick, J Pauletta, G Paulini, M Perazzo, A Pescara, L Peters, MD Phillips, TJ Piacentino, G Pillai, M Pitts, KT Plunkett, R Pompos, A Pondrom, L Proudfoot, J Ptohos, F Punzi, G Ragan, K Reher, D Reischl, M Ribon, A Rimondi, F Ristori, L Robertson, WJ Rodrigo, T Rolli, S Rosenson, L Roser, R Saab, T Sakumoto, WK Saltzberg, D Sansoni, A Santi, L Sato, H Schlabach, P Schmidt, EE Schmidt, MP Scott, A Scribano, A Segler, S Seidel, S Seiya, Y Semeria, F Shah, T Shapiro, MD Shaw, NM Shepard, PF Shibayama, T Shimojima, M Shochet, M Siegrist, J Sill, A Sinervo, P Singh, P Sliwa, K Smith, C Snider, FD Spalding, J Speer, T Sphicas, P Spinella, F Spiropulu, M Spiegel, L Stanco, L Steele, J Stefanini, A Strohmer, R Strologas, J Strumia, F Stuart, D Sumorok, K Suzuki, J Suzuki, T Takahashi, T Takano, T Takashima, R Takikawa, K Tanaka, M Tannenbaum, B Tartarelli, F Taylor, W Tecchio, M Teng, PK Teramoto, Y Terashi, K Tether, S Theriot, D Thomas, TL Thurman-Keup, R Timko, M Tipton, P Titov, A Tkaczyk, S Toback, D Tollefson, K Tollestrup, A Toyoda, H Trischuk, W de Troconiz, JF Truitt, S Tseng, J Turini, N Uchida, T Ukegawa, F Valls, J van den Brink, SC Vejcik, S Velev, G Vidal, R Vilar, R Vucinic, D Wagner, RG Wagner, RL Wahl, J Wallace, NB Walsh, AM Wang, C Wang, CH Wang, MJ Warburton, A Watanabe, T Watts, T Webb, R Wei, C Wenzel, H Wester, WC Wicklund, AB Wicklund, E Wilkinson, R Williams, HH Wilson, P Winer, BL Winn, D Wolinski, D Wolinski, J Worm, S Wu, X Wyss, J Yagil, A Yao, W Yasuoka, K Yeh, GP Yeh, P Yoh, J Yosef, C Yoshida, T Yu, I Zanetti, A Zetti, F Zucchelli, S AF Abe, F Akimoto, H Akopian, A Albrow, MG Amadon, A Amendolia, SR Amidei, D Antos, J Aota, S Apollinari, G Arisawa, T Asakawa, T Ashmanskas, W Atac, M Azzi-Bacchetta, P Bacchetta, N Bagdasarov, S Bailey, MW de Barbaro, P Barbaro-Galtieri, A Barnes, VE Barnett, BA Barone, M Bauer, G Baumann, T Bedeschi, F Behrends, S Belforte, S Bellettini, G Bellinger, J Benjamin, D Bensinger, J Beretvas, A Berge, JP Berryhill, J Bertolucci, S Bettelli, S Bevensee, B Bhatti, A Biery, K Bigongiari, C Binkley, M Bisello, D Blair, RE Blocker, C Blusk, S Bodek, A Bokhari, W Bolla, G Bonushkin, Y Bortoletto, D Boudreau, J Breccia, L Bromberg, C Bruner, N Brunetti, R Buckley-Geer, E Budd, HS Burkett, K Busetto, G Byon-Wagner, A Byrum, KL Campbell, M Caner, A Carithers, W Carlsmith, D Cassada, J Castro, A Cauz, D Cerri, A Chang, PS Chang, PT Chao, HY Chapman, J Cheng, MT Chertok, M Chiarelli, G Chiou, CN Chlebana, F Christofek, L Chu, ML Cihangir, S Clark, AG Cobal, M Cocca, E Contreras, M Convery, ME Conway, J Cooper, J Cordelli, M Costanzo, D Couyoumtzelis, C Cronin-Hennessy, D Culbertson, R Dagenhart, D Daniels, T DeJongh, F Dell'Agnello, S Dell'Orso, M Demina, R Demortier, L Deninno, M Derwent, PF Devlin, T Dittmann, JR Donati, S Done, J Dorigo, T Eddy, N Einsweiler, K Elias, JE Ely, R Engels, E Erdmann, W Errede, W Errede, S Fan, Q Feild, RG Feng, Z Ferretti, C Fiori, I Flaugher, B Foster, GW Franklin, M Freeman, J Friedman, J Frisch, H Fukui, Y Gadomski, S Galeotti, S Gallinaro, M Ganel, O Garcia-Sciveres, M Garfinkel, AF Gay, C Geer, S Gerdes, DW Giannetti, P Giokaris, N Giusti, G Gold, M Gordon, A Goshaw, AT Gotra, Y Goulianos, K Grassmann, H Groer, L Grosso-Pilcher, C Guillian, G da Costa, JG Guo, RS Haber, C Hafen, E Hahn, SR Hamilton, R Handa, T Handler, R Happacher, F Hara, K Hardman, AD Harris, RM Hartmann, F Hauser, J Hayashi, E Heinrich, J Hao, W Hinrichsen, B Hoffman, KD Hohlmann, M Holck, C Hollebeek, R Holloway, L Huang, Z Huffman, BT Hughes, R Huston, J Huth, J Ikeda, H Incagli, M Incandela, J Introzzi, G Iwai, J Iwata, Y James, E Jensen, H Joshi, U Kajfasz, E Kambara, H Kamon, T Kaneko, T Karr, K Kasha, H Kato, Y Keaffaber, TA Kelley, K Kennedy, RD Kephart, R Kestenbaum, D Khazins, D Kikuchi, T Kim, BJ Kim, HS Kim, SH Kim, YK Kirsch, L Klimenko, S Knoblauch, D Koehn, P Kongeter, A Kondo, K Konigsberg, J Kordas, K Korytov, A Kovacs, E Kowald, W Kroll, J Kruse, M Kuhlmann, SE Kuns, E Kurino, K Kuwabara, T Laasanen, AT Lami, S Lammel, S Lamoureux, JI Lancaster, M Lanzoni, M Latino, G LeCompte, T Leone, S Lewis, JD Lindgren, M Liss, TM Liu, JB Liu, YC Lockyer, N Long, O Loomis, C Loreti, M Lucchesi, D Lukens, P Lusin, S Lys, J Maeshima, K Maksimovic, P Mangano, M Mariotti, M Marriner, JP Martignon, G Martin, A Matthews, JAJ Mazzanti, P McFarland, K McIntrye, P Melese, P Menguzzato, M Menzione, A Meschi, E Mesropian, C Metzler, S Miao, C Miao, T Michail, G Miller, R Minato, H Miscetti, S Mishina, M Miyashita, S Moggi, N Moore, E Morita, Y Mukherjee, A Muller, T Murat, P Murgia, S Musy, M Nakada, H Nakaya, T Nakano, I Nelson, C Neuberger, D Newman-Holmes, C Ngan, CYP Nodulman, L Nomerotski, A Oh, SH Ohmoto, T Ohsugi, T Oishi, R Okabe, M Okusawa, T Olsen, J Pagliarone, C Paoletti, R Papadimitriou, V Pappas, SP Parashar, N Parri, A Patrick, J Pauletta, G Paulini, M Perazzo, A Pescara, L Peters, MD Phillips, TJ Piacentino, G Pillai, M Pitts, KT Plunkett, R Pompos, A Pondrom, L Proudfoot, J Ptohos, F Punzi, G Ragan, K Reher, D Reischl, M Ribon, A Rimondi, F Ristori, L Robertson, WJ Rodrigo, T Rolli, S Rosenson, L Roser, R Saab, T Sakumoto, WK Saltzberg, D Sansoni, A Santi, L Sato, H Schlabach, P Schmidt, EE Schmidt, MP Scott, A Scribano, A Segler, S Seidel, S Seiya, Y Semeria, F Shah, T Shapiro, MD Shaw, NM Shepard, PF Shibayama, T Shimojima, M Shochet, M Siegrist, J Sill, A Sinervo, P Singh, P Sliwa, K Smith, C Snider, FD Spalding, J Speer, T Sphicas, P Spinella, F Spiropulu, M Spiegel, L Stanco, L Steele, J Stefanini, A Strohmer, R Strologas, J Strumia, F Stuart, D Sumorok, K Suzuki, J Suzuki, T Takahashi, T Takano, T Takashima, R Takikawa, K Tanaka, M Tannenbaum, B Tartarelli, F Taylor, W Tecchio, M Teng, PK Teramoto, Y Terashi, K Tether, S Theriot, D Thomas, TL Thurman-Keup, R Timko, M Tipton, P Titov, A Tkaczyk, S Toback, D Tollefson, K Tollestrup, A Toyoda, H Trischuk, W de Troconiz, JF Truitt, S Tseng, J Turini, N Uchida, T Ukegawa, F Valls, J van den Brink, SC Vejcik, S Velev, G Vidal, R Vilar, R Vucinic, D Wagner, RG Wagner, RL Wahl, J Wallace, NB Walsh, AM Wang, C Wang, CH Wang, MJ Warburton, A Watanabe, T Watts, T Webb, R Wei, C Wenzel, H Wester, WC Wicklund, AB Wicklund, E Wilkinson, R Williams, HH Wilson, P Winer, BL Winn, D Wolinski, D Wolinski, J Worm, S Wu, X Wyss, J Yagil, A Yao, W Yasuoka, K Yeh, GP Yeh, P Yoh, J Yosef, C Yoshida, T Yu, I Zanetti, A Zetti, F Zucchelli, S TI Events with a rapidity gap between jets in (p)over-bar-p collisions at root s=630 GeV SO PHYSICAL REVIEW LETTERS LA English DT Article ID PARTON ELASTIC-SCATTERING; SINGULARITY; TEV AB We report a measurement of the fraction of dijet events with a rapidity gap between jets produced by color-singlet exchange in (p) over bar p collisions at root s = 630 GeV at the Fermilab Tevatron. In events with two jets of transverse energy E-T(jet) > 8 GeV, pseudorapidity in the range 1.8 < \n(jet)\ < 3.5 and eta(1)eta(2) < 0, the color-singlet exchange fraction is found to be R = [2.7 +/- 0.7(stat) +/- 0.6(syst)]%. Comparisons are made with results obtained at root s = 1800 GeV and with theoretical expectations. C1 Natl Lab High Energy Phys, KEK, Tsukuba, Ibaraki 305, Japan. Argonne Natl Lab, Argonne, IL 60439 USA. Univ Bologna, Ist Nazl Fis Nucl, I-40127 Bologna, Italy. Brandeis Univ, Waltham, MA 02254 USA. Univ Calif Los Angeles, Los Angeles, CA 90024 USA. Univ Chicago, Chicago, IL 60637 USA. Duke Univ, Durham, NC 27708 USA. Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Florida, Gainesville, FL 32611 USA. Ist Nazl Fis Nucl, Lab Nazl Frascati, I-00044 Frascati, Italy. Univ Geneva, CH-1211 Geneva 4, Switzerland. Harvard Univ, Cambridge, MA 02138 USA. Hiroshima Univ, Higashihiroshima 724, Japan. Univ Illinois, Urbana, IL 61801 USA. McGill Univ, Inst Particle Phys, Montreal, PQ H3A 2T8, Canada. Univ Toronto, Toronto, ON M5S 1A7, Canada. Johns Hopkins Univ, Baltimore, MD 21218 USA. Univ Karlsruhe, Inst Expt Kernphys, D-76128 Karlsruhe, Germany. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. MIT, Cambridge, MA 02139 USA. Univ Michigan, Ann Arbor, MI 48109 USA. Michigan State Univ, E Lansing, MI 48824 USA. Univ New Mexico, Albuquerque, NM 87131 USA. Ohio State Univ, Columbus, OH 43210 USA. Osaka City Univ, Osaka 588, Japan. Univ Padua, Ist Nazl Fis Nucl, I-35131 Padua, Italy. Univ Penn, Philadelphia, PA 19104 USA. Univ Pisa, Ist Nazl Fis Nucl, I-56100 Pisa, Italy. Scuola Normale Super Pisa, I-56100 Pisa, Italy. Univ Pittsburgh, Pittsburgh, PA 15260 USA. Purdue Univ, W Lafayette, IN 47907 USA. Univ Rochester, Rochester, NY 14627 USA. Rockefeller Univ, New York, NY 10021 USA. Rutgers State Univ, Piscataway, NJ 08855 USA. Acad Sinica, Taipei 11530, Taiwan. Texas A&M Univ, College Stn, TX 77843 USA. Texas Tech Univ, Lubbock, TX 79409 USA. Univ Trieste, Ist Nazl Fis Nucl, Udine, Italy. Univ Tsukuba, Tsukuba, Ibaraki 315, Japan. Tufts Univ, Medford, MA 02155 USA. Waseda Univ, Tokyo 169, Japan. Univ Wisconsin, Madison, WI 53706 USA. Yale Univ, New Haven, CT 06520 USA. RP Abe, F (reprint author), Natl Lab High Energy Phys, KEK, Tsukuba, Ibaraki 305, Japan. RI Lancaster, Mark/C-1693-2008; Vucinic, Dejan/C-2406-2008; Nomerotski, Andrei/A-5169-2010; Azzi, Patrizia/H-5404-2012; Punzi, Giovanni/J-4947-2012; Chiarelli, Giorgio/E-8953-2012; Warburton, Andreas/N-8028-2013; Paulini, Manfred/N-7794-2014; Introzzi, Gianluca/K-2497-2015 OI Azzi, Patrizia/0000-0002-3129-828X; Punzi, Giovanni/0000-0002-8346-9052; Chiarelli, Giorgio/0000-0001-9851-4816; Warburton, Andreas/0000-0002-2298-7315; Paulini, Manfred/0000-0002-6714-5787; Introzzi, Gianluca/0000-0002-1314-2580 NR 20 TC 48 Z9 48 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD DEC 14 PY 1998 VL 81 IS 24 BP 5278 EP 5283 DI 10.1103/PhysRevLett.81.5278 PG 6 WC Physics, Multidisciplinary SC Physics GA 147RN UT WOS:000077511700006 ER PT J AU Chen, S Foias, C Holm, DD Olson, E Titi, ES Wynne, S AF Chen, S Foias, C Holm, DD Olson, E Titi, ES Wynne, S TI Camassa-Holm equations as a closure model for turbulent channel and pipe flow SO PHYSICAL REVIEW LETTERS LA English DT Article ID LOW-REYNOLDS-NUMBER; STRESS; FLUIDS AB We propose the viscous Camassa-Holm equations as a closure approximation for the Reynolds-averaged equations of the incompressible Navier-Stokes fluid. This approximation is tested on turbulent channel and pipe flows with steady mean. Analytical solutions for the mean velocity and the Reynolds shear stress are consistent with experiments in most of the now region. C1 Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Univ Calif Los Alamos Natl Lab, Ctr Nonlinear Studies, Los Alamos, NM 87545 USA. Indiana Univ, Dept Math, Bloomington, IN 47405 USA. Univ Calif Irvine, Dept Math, Irvine, CA 92697 USA. Univ Calif Irvine, Dept Mech & Aerosp Engn, Irvine, CA 92697 USA. Univ Calif Los Alamos Natl Lab, Inst Geophys & Planetary Phys, Los Alamos, NM 87545 USA. RP Chen, S (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RI Chen, Shiyi/A-3234-2010; OI Holm, Darryl D/0000-0001-6362-9912 NR 25 TC 188 Z9 191 U1 0 U2 3 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD DEC 14 PY 1998 VL 81 IS 24 BP 5338 EP 5341 DI 10.1103/PhysRevLett.81.5338 PG 4 WC Physics, Multidisciplinary SC Physics GA 147RN UT WOS:000077511700021 ER PT J AU Kner, P Schafer, W Lovenich, R Chemla, DS AF Kner, P Schafer, W Lovenich, R Chemla, DS TI Coherence of four-particle correlations in semiconductors SO PHYSICAL REVIEW LETTERS LA English DT Article ID EXCITON-EXCITON; QUANTUM-WELL; RELAXATION; DYNAMICS AB We report direct investigations of the coherence of four-particle (exciton-exciton) correlations by ultrafast four-wave mixing experiments. We determine the sensitivity of the coherence of the four-particle correlations to temperature and excitation density, comparing it to the coherence of the two-particle correlations. We discuss our results in terms of numerical solutions of the general kinetic equations, treating the four-particle correlations in the second order Born approximation. We introduce a simple model deduced from these kinetic equations that provides an intuitive interpretation of our results. C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Hochstleistungsrechenzentrum Forschungszentrum, Julich, Germany. RP Kner, P (reprint author), Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. NR 21 TC 78 Z9 78 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD DEC 14 PY 1998 VL 81 IS 24 BP 5386 EP 5389 DI 10.1103/PhysRevLett.81.5386 PG 4 WC Physics, Multidisciplinary SC Physics GA 147RN UT WOS:000077511700033 ER PT J AU Zheludev, A Maslov, S Tsukada, I Zaliznyak, I Regnault, LP Masuda, T Uchinokura, K Erwin, R Shirane, G AF Zheludev, A Maslov, S Tsukada, I Zaliznyak, I Regnault, LP Masuda, T Uchinokura, K Erwin, R Shirane, G TI Experimental evidence for Kaplan-Shekhtman-Entin-Wohlman-Aharony interactions in Ba2CuGe2O7 SO PHYSICAL REVIEW LETTERS LA English DT Article ID ANISOTROPIC SUPEREXCHANGE INTERACTION; SPIN-ORBIT; WEAK FERROMAGNETISM; MAGNETIC-FIELD; ANTIFERROMAGNET; PHASE; FRUSTRATION; SCATTERING AB New neutron diffraction and inelastic neutron scattering experiments on Ba2CuGe2O7 suggest that the previously suggested model for the magnetism of this material (an ideal sinusoidal spin spiral, stabilized by isotropic exchange and Dzyaloshinskii-Moriya interactions) needs to be refined. Both new and previously published experimental results can be quantitatively explained by taking into account the Kaplan-Shekhtman-Entin-Wohlman-Aharony term, a special anisotropy term that was predicted to always accompany Dzyaloshinskii-Moriya interactions in insulators. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. Univ Tokyo, Dept Appl Phys, Bunkyo Ku, Tokyo 1138656, Japan. NIST, Ctr Neutron Res, Gaithersburg, MD 20899 USA. Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. PL Kapitza Phys Problems Inst, Moscow, Russia. CENG, MDN, SPSMS, RFMC, F-38054 Grenoble, France. RP Brookhaven Natl Lab, Upton, NY 11973 USA. RI Zaliznyak, Igor/E-8532-2014; Maslov, Sergei/C-2397-2009 OI Zaliznyak, Igor/0000-0002-9886-3255; Maslov, Sergei/0000-0002-3701-492X NR 19 TC 29 Z9 29 U1 1 U2 9 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 EI 1079-7114 J9 PHYS REV LETT JI Phys. Rev. Lett. PD DEC 14 PY 1998 VL 81 IS 24 BP 5410 EP 5413 DI 10.1103/PhysRevLett.81.5410 PG 4 WC Physics, Multidisciplinary SC Physics GA 147RN UT WOS:000077511700039 ER PT J AU Mitkov, I Kladko, K Pearson, JE AF Mitkov, I Kladko, K Pearson, JE TI Tunable pinning of burst waves in extended systems with discrete sources SO PHYSICAL REVIEW LETTERS LA English DT Article ID DYNAMICS; CALCIUM; MODEL AB We study the dynamics of waves in a system of diffusively coupled discrete nonlinear sources. We show that the system exhibits burst waves which are periodic in a traveling-wave reference frame. We demonstrate that the burst waves are pinned if the diffusive coupling is below a critical value. When the coupling crosses the critical value the system undergoes a depinning instability via a saddle-node bifur cation, and the wave begins to move. We obtain the universal scaling for the mean wave velocity just above threshold. [S0031-9007(98)07893-4]. C1 Univ Calif Los Alamos Natl Lab, Ctr Nonlinear Studies, Computat Sci Methods Grp, Los Alamos, NM 87545 USA. Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Mitkov, I (reprint author), Univ Calif Los Alamos Natl Lab, Ctr Nonlinear Studies, Computat Sci Methods Grp, Los Alamos, NM 87545 USA. NR 20 TC 36 Z9 36 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD DEC 14 PY 1998 VL 81 IS 24 BP 5453 EP 5456 DI 10.1103/PhysRevLett.81.5453 PG 4 WC Physics, Multidisciplinary SC Physics GA 147RN UT WOS:000077511700050 ER PT J AU Hannon, JB Bartelt, NC Swartzentruber, BS Hamilton, JC Kellogg, GL AF Hannon, JB Bartelt, NC Swartzentruber, BS Hamilton, JC Kellogg, GL TI Step faceting at the (001) surface of boron doped silicon - Hannon et al. reply SO PHYSICAL REVIEW LETTERS LA English DT Article C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Hannon, JB (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 2 TC 1 Z9 1 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD DEC 14 PY 1998 VL 81 IS 24 BP 5474 EP 5474 DI 10.1103/PhysRevLett.81.5474 PG 1 WC Physics, Multidisciplinary SC Physics GA 147RN UT WOS:000077511700059 ER PT J AU Reginatto, M AF Reginatto, M TI Derivation of the Pauli equation using the principle of minimum Fisher information SO PHYSICS LETTERS A LA English DT Article DE Pauli equation; Fisher information AB It is shown that the Pauli equation formulated in terms of hydrodynamical variables can be derived using the principle of minimum Fisher information. (C) 1998 Elsevier Science B.V. C1 US DOE, Environm Measurements Lab, New York, NY 10014 USA. RP Reginatto, M (reprint author), US DOE, Environm Measurements Lab, 201 Varick St,5th Floor, New York, NY 10014 USA. NR 12 TC 15 Z9 15 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9601 J9 PHYS LETT A JI Phys. Lett. A PD DEC 14 PY 1998 VL 249 IS 5-6 BP 355 EP 357 DI 10.1016/S0375-9601(98)00773-7 PG 3 WC Physics, Multidisciplinary SC Physics GA 148KC UT WOS:000077503000002 ER PT J AU Tilinin, IS Rose, MK Dunphy, JC Salmeron, M Van Hove, MA AF Tilinin, IS Rose, MK Dunphy, JC Salmeron, M Van Hove, MA TI Identification of adatoms on metal surfaces by STM: experiment and theory SO SURFACE SCIENCE LA English DT Article DE adatoms; chemisorption; palladium; scanning tunneling microscopy; single crystal surfaces; theoretical calculations ID SCANNING TUNNELING MICROSCOPE; ATOM; MANIPULATION; CONDUCTANCE; ADSORBATES; BENZENE; IMAGES; SITE; TIP AB The possibility of identifying the chemical nature of atomic adsorbates (C, N, O, F and S) on metal surfaces has been explored both theoretically and experimentally. It is shown that, although the tip and the surface may markedly influence the appearance of adatoms in STM images, atomic size and electronegativity are the dominant factors that determine the contrast. In this work, low-temperature (<40 K) STM is used to suppress adatom diffusion on the Pd(lll) surface and to image isolated adsorbates at low coverages. It is found experimentally that isolated carbon and sulfur atoms on the Pd(ll) surface scanned by a platinum tip appear as bumps with a height of about 0.3-0.4 Angstrom and 0.8 Angstrom, respectively, whereas oxygen atoms are characterized by a depression with a negative corrugation of -0.35 Angstrom. To simulate STM images of adatoms on metal surfaces, we have applied Green's function formalism to solve the Schrodinger equation in the tight binding approximation. It is shown that highly electronegative atoms such as O and F always appear as depressions. As the electronegativity decreases (from F to C), the depression transforms into a shallow dimple with a slight bump in the middle in the case of N, and into a well-pronounced bump for C. Third-row adsorbates (Na through Cl) are also calculated to produce bumps, with a corrugation that does not correlate simply with the adatom-surface spacing. The shape and size of the image corrugations predicted theoretically are in good agreement with the experimental data. (C) 1998 Published by Elsevier Science B.V. All rights reserved. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Van Hove, MA (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RI Van Hove, Michel/A-9862-2008 OI Van Hove, Michel/0000-0002-8898-6921 NR 40 TC 29 Z9 29 U1 0 U2 14 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 J9 SURF SCI JI Surf. Sci. PD DEC 14 PY 1998 VL 418 IS 3 BP 511 EP 520 DI 10.1016/S0039-6028(98)00749-3 PG 10 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA 153XB UT WOS:000077857600006 ER PT J AU Zasada, I Van Hove, MA Somorjai, GA AF Zasada, I Van Hove, MA Somorjai, GA TI Reanalysis of the Rh(111)+(2x2)-3NO structure using automated tensor LEED SO SURFACE SCIENCE LA English DT Letter DE chemisorption; electron-solid interactions; low energy electron diffraction; low index single crystal surfaces; metallic surfaces; nitrogen oxides; rhodium ID SIMULTANEOUS BRIDGE; SURFACE-STRUCTURE; CO; ADSORPTION; RH(111); SITES; CHEMISORPTION; DIFFRACTION; GEOMETRY; NO AB The structure of Rh(111)+(2 x 2)-3NO has been reanalyzed using automated tensor LEED, in view of new results which strongly suggest different molecular adsorption sites to those previously concluded. The reanalysis confirms and further refines the new model, according to which the NO molecules occupy top sites and both kinds of three-fold hollow sites. These findings are at odds with earlier conclusions from vibrational spectroscopy, which assigned the molecules to top and bridge sites. Together with other metal/NO and metal/CO systems described in the literature, the Rh(111)+(2 x 2)-3NO phase once again demonstrates that great care has to be taken in adsorption site assignment using the C-O and especially the N-O stretch frequencies. (C) 1998 Published by Elsevier Science B.V. All rights reserved. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Univ Lodz, Dept Solid State Phys, PL-90131 Lodz, Poland. Univ Calif Davis, Dept Phys, Livermore, CA 95616 USA. Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. RP Van Hove, MA (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RI Van Hove, Michel/A-9862-2008 OI Van Hove, Michel/0000-0002-8898-6921 NR 18 TC 32 Z9 32 U1 0 U2 10 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 J9 SURF SCI JI Surf. Sci. PD DEC 14 PY 1998 VL 418 IS 3 BP L89 EP L93 DI 10.1016/S0039-6028(98)00782-1 PG 5 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA 153XB UT WOS:000077857600002 ER PT J AU Wood, BD AF Wood, BD TI A connection between the Lagrangian stochastic-convective and cumulant expansion approaches for describing solute transport in heterogeneous porous media SO ADVANCES IN WATER RESOURCES LA English DT Article DE stochastic groundwater transport; cumulant expansion; stochastic-convective dispersion ID RANDOM VELOCITY-FIELD; PERTURBATION EXPANSION; GENERALIZED CUMULANT; THEORETICAL-ANALYSIS; DISPERSION; SCALE; AQUIFERS; GROUNDWATER; APPROXIMATION; MOMENTS AB The equation describing the ensemble-average solute concentration in a heterogeneous porous media can be developed from the Lagrangian (stochastic-convective) approach and from a method that uses a renormalized cumulant expansion. These two approaches are compared for the case of steady flow, and it is shown that they are related. The cumulant expansion approach can be interpreted as a series expansion of the convolution path integral that defines the ensemble-average concentration in the La,Lagrangian approach. The two methods can be used independently to develop the classical form for the convection-dispersion equation, and are shown to lead to identical transport equations under certain simplifying assumptions. In the development of such transport equations, the cumulant expansion does not require a priori the assumption of any particular distribution for the Lagrangian displacements or velocity field, and does not require one to approximate trajectories with their ensemble-average. In order to obtain a second-order equation, the cumulant expansion method does require truncation of a series, but this truncation is done rationally by the development of a constraint in terms of parameters of the transport field. This constraint is less demanding than requiring that the distribution for the Lagrangian displacements be strictly Gaussian, and it indicates under what velocity field conditions a second-order transport equation is a reasonable approximation. (C) 1998 Elsevier Science Limited. All rights reserved. C1 Univ Calif Davis, Dept Civil & Environm Engn, Davis, CA 95616 USA. Pacific NW Lab, Richland, WA 99352 USA. RP Univ Calif Davis, Dept Civil & Environm Engn, Davis, CA 95616 USA. RI Wood, Brian/K-4025-2012; Wood, Brian/J-8362-2013 OI Wood, Brian/0000-0003-3152-7852; Wood, Brian/0000-0003-3152-7852 NR 60 TC 9 Z9 9 U1 0 U2 0 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0309-1708 EI 1872-9657 J9 ADV WATER RESOUR JI Adv. Water Resour. PD DEC 11 PY 1998 VL 22 IS 4 BP 319 EP 332 DI 10.1016/S0309-1708(98)00018-9 PG 14 WC Water Resources SC Water Resources GA 149TQ UT WOS:000077622200002 ER PT J AU Pickering, TJ Prince, RC Divers, T George, GN AF Pickering, TJ Prince, RC Divers, T George, GN TI Sulfur K-edge X-ray absorption spectroscopy for determining the chemical speciation of sulfur in biological systems SO FEBS LETTERS LA English DT Article DE sulfur; X-ray absorption spectroscopy ID ORGANIC SULFUR; PETROLEUM ASPHALTENES; ASCIDIA-CERATODES; SITE; SULFATE; OXIDASE; SPECTRA; CELLS; FORMS; COALS AB Sulfur is an essential biological element, yet its biochemistry is only partially understood because there are so few tools for studying this element in biological systems. X-ray absorption spectroscopy provides a unique approach to determining the chemical speciation of sulfur in intact biological samples. Different biologically relevant sulfur compounds show distinctly different sulfur K-edge X-ray absorption spectra, and we show here, as an example, that this allows the deconvolution of the sulfur species in equine blood. (C) 1998 Federation of European Biochemical Societies. C1 Stanford Univ, Stanford Synchrotron Radiat Lab, Stanford, CA 94309 USA. Exxon Res & Engn Co, Annandale, NJ 08801 USA. Cornell Univ, Coll Vet Med, Ithaca, NY 14853 USA. RP Pickering, TJ (reprint author), Stanford Univ, Stanford Synchrotron Radiat Lab, POB 4349,MS 69, Stanford, CA 94309 USA. RI George, Graham/E-3290-2013; OI Pickering, Ingrid/0000-0002-0936-2994 NR 21 TC 23 Z9 23 U1 1 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0014-5793 J9 FEBS LETT JI FEBS Lett. PD DEC 11 PY 1998 VL 441 IS 1 BP 11 EP 14 PG 4 WC Biochemistry & Molecular Biology; Biophysics; Cell Biology SC Biochemistry & Molecular Biology; Biophysics; Cell Biology GA 149XJ UT WOS:000077631800003 ER PT J AU Hang, B Sagi, J Singer, B AF Hang, B Sagi, J Singer, B TI Correlation between sequence-dependent glycosylase repair and the thermal stability of oligonucleotide duplexes containing 1,N-6-ethenoadenine SO JOURNAL OF BIOLOGICAL CHEMISTRY LA English DT Article ID HUMAN 3-METHYLADENINE-DNA GLYCOSYLASE; DNA-POLYMERASE INSERTION; ESCHERICHIA-COLI; NUCLEOTIDE EXCISION; HELIX STABILITY; BASE SEQUENCE; ADDUCT; KINETICS; PURIFICATION; SPECIFICITY AB Previous experiments on DNA sequence context reported that base modification, replication, and repair are affected by the nature of neighbor bases. We now report that repair by mammalian alkylpurine-DNA-N-glycosylases (APNG) of 15-mer oligonucleotides with a central 1,N-6-ethenoadenine (epsilon A), flanked by 5' and 3' tandem bases, is also highly sequence dependent. Oligonucleotides with the central sequences -GG epsilon AGG- or -CC epsilon ACC- are repaired 3-5-fold more efficiently than those containing -AA epsilon AAA- or -TT epsilon ATT- when using human or mouse APNG, Melting curves of the same duplexes showed that oligomers with G.C/C.G neighbors were less denatured than those with A.T/T.A neighbors at 37 degrees C. This sequence-dependent difference in denaturation correlates with the relative thermodynamic stability of oligomers with G.C/C.G or A.T/T.A neighbors. The dependence of repair on thermal stability was confirmed by enzyme reactions performed over 0-45 degrees C. Under these conditions, repair of epsilon A flanked by G.C/C.G was dramatically increased at 37 degrees C with continuous increase up to 45 degrees C, in contrast to that with flanking A.T/T.A pairs, which was in agreement with the degree of denaturation of these duplexes, These results indicate that the thermodynamic stability conferred by base pairs flanking epsilon A plays an essential role in maintaining the integrity of the duplex structure which is necessary for repair. C1 Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Donner Lab, Berkeley, CA 94720 USA. RP Singer, B (reprint author), Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Donner Lab, Berkeley, CA 94720 USA. FU NCI NIH HHS [CA 47723, CA 72079] NR 70 TC 29 Z9 29 U1 0 U2 1 PU AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 USA SN 0021-9258 J9 J BIOL CHEM JI J. Biol. Chem. PD DEC 11 PY 1998 VL 273 IS 50 BP 33406 EP 33413 DI 10.1074/jbc.273.50.33406 PG 8 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 146YY UT WOS:000077462500047 PM 9837917 ER PT J AU Smith, MS Guiochon, G AF Smith, MS Guiochon, G TI Theoretical analysis of the behavior of an heterogeneously packed chromatographic column SO JOURNAL OF CHROMATOGRAPHY A LA English DT Article; Proceedings Paper CT International Symposium on Preparative Chromatography CY MAY 31-JUN 03, 1998 CL WASHINGTON, D.C. SP Washington Chromatog Discuss Grp DE band profiles; column packings; preparative chromatography ID DISPERSION COEFFICIENTS; CONSOLIDATION; TRANSVERSE; PACKING; BEDS AB The properties of a chromatographic column packed with a nonhomogeneous mixture of two slightly different packing materials are studied by calculating the migration, the broadening, and the shape alteration of a rectangular band moving under nonlinear conditions along such a column. For the sake of simplicity, the column bed is assumed to be an alternate set of coaxial annular columns of the two materials. A two-dimensional implementation of the equilibrium-dispersive model permits the study of problems of this type, requiring two space dimensions for their modeling, such as this nonhomogeneous column with cylindrical symmetry, a nonplanar injection with a cylindrical symmetry, or a cylindrical central injection. The axial and radial profiles of the band inside the column and its elution profiles are calculated. These profiles depend on both the radial and the axial dispersion coefficients and on the relative difference between the separation factor of the two materials. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Guiochon, G (reprint author), Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. NR 12 TC 10 Z9 10 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0021-9673 J9 J CHROMATOGR A JI J. Chromatogr. A PD DEC 11 PY 1998 VL 827 IS 2 BP 241 EP 257 DI 10.1016/S0021-9673(98)00810-3 PG 17 WC Biochemical Research Methods; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA 153KP UT WOS:000077832500009 ER PT J AU Frit, P Calsou, P Chen, DJ Salles, B AF Frit, P Calsou, P Chen, DJ Salles, B TI Ku70/Ku80 protein complex inhibits the binding of nucleotide excision repair proteins on linear DNA in vitro SO JOURNAL OF MOLECULAR BIOLOGY LA English DT Article DE DNA repair; DNA damage; Ku autoantigen; DNA-PK; double-strand breaks ID CELL-FREE-EXTRACTS; IN-VITRO; KU AUTOANTIGEN; DAMAGED DNA; RECOMBINATION; KINASE; INCISION; TRANSCRIPTION; MECHANISM; NUCLEASE AB We have previously reported that the incision efficiency of the nucleotide excision repair (NER) reaction measured in vitro with cell-free human protein extracts was reduced by up to 80% on a Linearized damaged plasmid DNA substrate when compared to supercoiled damaged DNA. The inhibition stemed from the presence of the DNA-end binding Ku70/Ku80 heterodimer which is the regulatory subunit of the DNA-dependent protein kinase (DNA-PK). Here, the origin of the repair inhibition was assessed by a new in vitro assay in which circular or linear plasmid DNA, damaged or undamaged, was quantitatively adsorbed on sensitized microplate wells. The binding of two NER proteins, XPA and p62-TFIIH, indispensable for the incision step of the reaction, was quantified either directly in an ELISA-like reaction in the wells with specific antibodies or in Western blotting experiments on the DNA-bound fraction. We report a dramatic inhibition of XPA and p62-TFIIH association with WC photoproducts on linear DNA. XPA and p62-TFIIH binding to DNA damage was regained when the reaction was performed with extracts lacking Ku activity (extracts from xrs6 rodent cells) whereas addition of purified human Ku complex to these extracts restored the inhibition. Despite the fact that DNA-PK was active during the NER reaction, the mechanism of inhibition relied on the sole Ku complex, since mutant protein extracts lacking the catalytic DNA-PK subunit (extracts from the human M059J glioma cells) exhibited a strong binding inhibition of XPA and p62-TFIIH proteins on linear damaged DNA, identical to the inhibition observed with the DNA-PK+ control extracts (from M059K cells). (C) 1998 Academic Press. C1 Inst Pharmacol & Biol Struct, CNRS, UPR 9062, F-31077 Toulouse, France. Univ Calif Los Alamos Natl Lab, Div Life Sci, DNA Damage & Repair Grp, Los Alamos, NM 87545 USA. RP Calsou, P (reprint author), Inst Pharmacol & Biol Struct, CNRS, UPR 9062, 205 Route Narbonne, F-31077 Toulouse, France. RI salles, bernard/B-8531-2008 NR 44 TC 12 Z9 12 U1 1 U2 2 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0022-2836 J9 J MOL BIOL JI J. Mol. Biol. PD DEC 11 PY 1998 VL 284 IS 4 BP 963 EP 973 DI 10.1006/jmbi.1998.2257 PG 11 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 147BD UT WOS:000077467300012 PM 9837719 ER PT J AU Chiu, CY Cary, RB Chen, DJ Peterson, SR Stewart, PL AF Chiu, CY Cary, RB Chen, DJ Peterson, SR Stewart, PL TI Cryo-EM imaging of the catalytic subunit of the DNA-dependent protein kinase SO JOURNAL OF MOLECULAR BIOLOGY LA English DT Article DE cryo-electron microscopy; DNA-dependent protein kinase; DNA-PK; double-strand break repair; image reconstruction ID STRAND-BREAK-REPAIR; RNA POLYMERASE-II; ELECTRON-MICROSCOPY; V(D)J RECOMBINATION; NONSENSE MUTATION; SCID MUTATION; KU; DEFICIENCY; MECHANISM; BINDING AB The DNA-dependent protein kinase (DNA-PK) plays an important role in mammalian DNA double-strand break repair and immunoglobulin gene rearrangement. The DNA-PK holoenzyme is activated by assembly at DNA ends and is comprised of DNA-PKcs, a 460 kDa protein kinase catalytic subunit, and Ku, a 70 kDa/80 kDa heterodimeric DNA-targeting component. We have solved the three-dimensional structure of DNA-PKcs to similar to 21 Angstrom resolution by analytically combining images of nearly 9500 individual particles extracted from cryoelectron micrographs. The DNA-PKcs protein has an open, pseudo 2-fold symmetric structure with a gap separating a crown-shaped top from a rounded base. Columns of density are observed to protrude into the gap from both the crown and the base. Measurements of the enclosed volume indicate that the interior of the protein is largely hollow. The structure of DNA-PKcs suggests that its association with DNA may involve the internalization of double-stranded ends. C1 Univ Calif Los Angeles, Sch Med, Crump Inst Biol Imaging, Dept Mol & Med Pharmacol, Los Angeles, CA 90095 USA. Univ Calif Los Alamos Natl Lab, Div Life Sci, Los Alamos, NM 87545 USA. RP Stewart, PL (reprint author), Univ Calif Los Angeles, Sch Med, Crump Inst Biol Imaging, Dept Mol & Med Pharmacol, Los Angeles, CA 90095 USA. EM pstewart@mednet.ucla.edu OI Chiu, Charles/0000-0003-2915-2094 FU NIGMS NIH HHS [GM08042] NR 35 TC 56 Z9 56 U1 0 U2 1 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0022-2836 J9 J MOL BIOL JI J. Mol. Biol. PD DEC 11 PY 1998 VL 284 IS 4 BP 1075 EP 1081 DI 10.1006/jmbi.1998.2212 PG 7 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 147BD UT WOS:000077467300020 PM 9837727 ER PT J AU Marshall, SL AF Marshall, SL TI On the analytical summation of Fourier series and its relation to the asymptotic behaviour of Fourier transforms SO JOURNAL OF PHYSICS A-MATHEMATICAL AND GENERAL LA English DT Article AB Forms of the Poisson summation formula (PSF) appropriate for the summation of semi-infinite and infinite Fourier series are derived. Application of these results to the acceleration of convergence of various types of series with monotonically decreasing coefficient functions yields transformed series with terms that decay either exponentially or with the inverse first or second power of the index variable. These two very different convergence properties are explained in terms of the asymptotic properties of the relevant Fourier transforms, which are in turn related to the power series expansions of the summand functions in the original Fourier series. The result is that the Poisson summation formula works best for Fourier cosine series in which the summand functions are expansible in even powers, and for Fourier sine series in which the summand functions have power series with odd powers. Here, application of the PSF produces series of terms that decay exponentially with increasing argument x. In contrast, application of the semi-infinite version of the PSF to Fourier cosine series of terms with odd-power expansions, or to Fourier sine series of terms with even-power expansions yields transformed series involving functions of the form exp(x)E-1(x) +/- exp(-x) Ei(x), which decay approximately as 1/x. If the summand function in the Fourier series has a power series with both even and odd powers, the transformed series involves sine and cosine integral functions, which decay approximately as 1/x(2). Fourier series of these last three types in general require additional acceleration, for example, by application of the Kummer transformation. C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Marshall, SL (reprint author), Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RI Marshall, Simon/E-9518-2010 NR 25 TC 2 Z9 2 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0305-4470 J9 J PHYS A-MATH GEN JI J. Phys. A-Math. Gen. PD DEC 11 PY 1998 VL 31 IS 49 BP 9957 EP 9973 DI 10.1088/0305-4470/31/49/014 PG 17 WC Physics, Multidisciplinary; Physics, Mathematical SC Physics GA 152AP UT WOS:000077753400014 ER PT J AU Burger, J Carruth-Hinchey, C Ondroff, E McMahon, M Gibbons, JW Gochfeld, M AF Burger, J Carruth-Hinchey, C Ondroff, E McMahon, M Gibbons, JW Gochfeld, M TI Effects of lead on behavior, growth, and survival of hatchling slider turtles SO JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH-PART A LA English DT Article ID YOUNG HERRING-GULLS; LOW PH; SIERRA-NEVADA; EXPOSURE; ALUMINUM; AMPHIBIANS; CALIFORNIA AB In this study the effects of lead on behavioral development of hatchling slider turtles (Trachemys scripta) from the Savannah River Site, near Aiken, SC, were examined. It was of interest to determine whether dose or size affects survival, growth, or behavior. Hatchlings from 1995 showed no significant differences in growth, survival, or behavior between control and lead-injected animals at a dose of 0.05 and 0.1 mg/g (n = 10 per group). In 1996, 48 hatchlings were divided into four groups injected with 0 (control), 0.25, 1, or 2.5 mg/g lead. Few significant differences occurred in growth or size as a function of lead treatment at 4 mo of age, but survival declined markedly as a function of lead dose. Righting response was significantly impaired by lead; time to right was directly related to lead dose. Size also affected behavior; larger hatchlings turned over more quickly and reached cover sooner than did smaller hatchlings. C1 Rutgers State Univ, Div Life Sci, Nelson Biol Lab, Grad Program Ecol & Evolut, Piscataway, NJ 08854 USA. Environm & Occupat Hlth Sci Inst, Piscataway, NJ USA. Univ Georgia, Savannah River Ecol Lab, Aiken, SC USA. Univ Med & Dent New Jersey, Robert Wood Johnson Med Sch, Environm & Occupat Hlth Sci Inst, Piscataway, NJ 08854 USA. RP Burger, J (reprint author), Rutgers State Univ, Div Life Sci, Nelson Biol Lab, Grad Program Ecol & Evolut, Nelson Hall,604 Allison Rd, Piscataway, NJ 08854 USA. EM burger@biology.rutgers.edu FU NIEHS NIH HHS [ESO 5022] NR 27 TC 22 Z9 22 U1 1 U2 7 PU TAYLOR & FRANCIS LTD PI LONDON PA ONE GUNPOWDER SQUARE, LONDON EC4A 3DE, ENGLAND SN 0098-4108 J9 J TOXICOL ENV HEAL A JI J. TOXICOL. ENV. HEALTH PT A PD DEC 11 PY 1998 VL 55 IS 7 BP 495 EP 502 DI 10.1080/009841098158296 PG 8 WC Environmental Sciences; Public, Environmental & Occupational Health; Toxicology SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Toxicology GA 143EN UT WOS:000077242200003 PM 9860323 ER PT J AU DeSchepper, D Kramer, LH Pate, SF Ackerstaff, K Carr, RW Court, GR Dvoredsky, A Gao, H Golendoukhin, A Hansen, JO Holler, Y Jones, CE Kelsey, JF Kinney, E Korsch, W Lee, K Martin, JW McKeown, RD Milner, RG Niczyporuk, M Pitt, ML Poolman, HR Roper, G Shin, T Sowinski, J Steffens, E Stewart, J Stock, F Sutter, M Tallini, H Tipton, B vanBommel, R Wise, T Zapfe-Duren, K AF DeSchepper, D Kramer, LH Pate, SF Ackerstaff, K Carr, RW Court, GR Dvoredsky, A Gao, H Golendoukhin, A Hansen, JO Holler, Y Jones, CE Kelsey, JF Kinney, E Korsch, W Lee, K Martin, JW McKeown, RD Milner, RG Niczyporuk, M Pitt, ML Poolman, HR Roper, G Shin, T Sowinski, J Steffens, E Stewart, J Stock, F Sutter, M Tallini, H Tipton, B vanBommel, R Wise, T Zapfe-Duren, K TI The HERMES polarized He-3 internal gas target SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article ID DEEP INELASTIC-SCATTERING; STRUCTURE-FUNCTION G1(X); PROTON SPIN STRUCTURE; STORAGE CELL; ASYMMETRY; RELAXATION; LASER; BEAM AB The HERMES experiment is investigating the spin structure of the proton and neutron via deep-inelastic scattering of polarized positrons from polarized nuclear targets. The polarized positrons are provided by the HERA positron storage ring at DESY, Hamburg, Germany. The targets are pure internal gas targets. Data acquisition began in 1995, utilizing polarized He-3 internal gas target to study the spin structure of the neutron. The target gas was polarized using the metastability-exchange optical-pumping technique and then injected into a cryogenically cooled target cell. The target was designed to operate with either longitudinal or transverse directions of polarization. Operating conditions included polarizations of up to 54% and target thicknesses of 1 x 10(15) nucleons/cm(2). In this paper the HERMES polarized He-3 internal gas target is described in detail. (C) 1998 Published by Elsevier Science B.V. All rights reserved. C1 MIT, Bates Linear Accelerator Ctr, Cambridge, MA 02139 USA. MIT, Nucl Sci Lab, Cambridge, MA 02139 USA. New Mexico State Univ, Dept Phys, Las Cruces, NM 88003 USA. DESY, D-22603 Hamburg, Germany. CALTECH, WK Kellogg Radiat Lab, Pasadena, CA 91125 USA. Univ Liverpool, Dept Phys, Liverpool L69 3BX, Merseyside, England. Univ Illinois, Dept Phys, Urbana, IL 61801 USA. Max Planck Inst Kernphys, D-69029 Heidelberg, Germany. Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. Univ Colorado, Dept Phys, Boulder, CO 80309 USA. Indiana Univ, Cyclotron Facil, Bloomington, IN 47408 USA. Univ Erlangen Nurnberg, Inst Phys, D-91058 Erlangen, Germany. Univ Wisconsin, Dept Phys, Madison, WI 53706 USA. NIKHEF K, NL-1009 DB Amsterdam, Netherlands. RP Milner, RG (reprint author), MIT, Bates Linear Accelerator Ctr, 77 Massachusetts Ave, Cambridge, MA 02139 USA. EM milner@mitlns.mit.edu RI Gao, Haiyan/G-2589-2011 NR 39 TC 18 Z9 18 U1 1 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD DEC 11 PY 1998 VL 419 IS 1 BP 16 EP 44 DI 10.1016/S0168-9002(98)00901-2 PG 29 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 144GX UT WOS:000077306900002 ER PT J AU Adeva, B Arik, E Arvidson, A Badelek, B Baum, G Berglund, P Betev, L de Botton, N Bradamante, F Bradtke, C Bravar, A Bultmann, S Crabb, D Cranshaw, J Cuhadar, T Dalla Torre, S van Dantzig, R Derro, B Deshpande, A Dhawan, S Dulya, C Dutz, H Eichblatt, S Fasching, D Feinstein, F Fernandez, C Forthmann, S Frois, B Gallas, A Garzon, JA Gehring, R Gilly, H Giorgi, M Goertz, S Gracia, G de Groot, N Perdekamp, MG Haft, K Harmsen, J von Harrach, D Hasegawa, T Hautle, P Hayashi, N Heusch, CA Horikawa, N Hughes, VM Igo, G Ishimoto, S Iwata, T Kabuss, EM Kageya, T Karev, A Ketel, TJ Kiryluk, J Kisselev, Y Kok, E Kramer, D Kroger, W Kurek, K Kyynarainen, J Lamanna, M Landgraf, U Le Goff, JM Lehar, F de Lesquen, A Lichtenstadt, J Litmaath, M Magnon, A Mallot, GK Martin, A Matsuda, T Mayes, B McCarthy, JS Medved, K Meyer, W van Middelkoop, G Miller, D Miyachi, Y Mori, K Nassalski, J Niinikoski, TO Oberski, JEJ Ogawa, A Parks, DP da Costa, HP Perrot-Kunne, F Peshekhonov, D Pinsky, L Platchkov, S Plo, M Pluckthun, M Polec, J Pose, D Postma, H Pretz, J Puntaferro, R Radel, G Reicherz, G Rijllart, A Rodriguez, M Rondio, E Sandacz, A Savin, I Schiavon, P Schiller, A Sichtermann, EP Simeoni, F Smirnov, GI Staude, A Steinmetz, A Stiegler, U Stuhrmann, H Tessarotto, F Tlaczala, W Tripet, A Unel, G Velasco, M Vogt, J Voss, R Whitten, C Windmolders, R Wislicki, W Witzmann, A Ylostalo, J Zanetti, AM Zaremba, K AF Adeva, B Arik, E Arvidson, A Badelek, B Baum, G Berglund, P Betev, L de Botton, N Bradamante, F Bradtke, C Bravar, A Bultmann, S Crabb, D Cranshaw, J Cuhadar, T Dalla Torre, S van Dantzig, R Derro, B Deshpande, A Dhawan, S Dulya, C Dutz, H Eichblatt, S Fasching, D Feinstein, F Fernandez, C Forthmann, S Frois, B Gallas, A Garzon, JA Gehring, R Gilly, H Giorgi, M Goertz, S Gracia, G de Groot, N Perdekamp, MG Haft, K Harmsen, J von Harrach, D Hasegawa, T Hautle, P Hayashi, N Heusch, CA Horikawa, N Hughes, VM Igo, G Ishimoto, S Iwata, T Kabuss, EM Kageya, T Karev, A Ketel, TJ Kiryluk, J Kisselev, Y Kok, E Kramer, D Kroger, W Kurek, K Kyynarainen, J Lamanna, M Landgraf, U Le Goff, JM Lehar, F de Lesquen, A Lichtenstadt, J Litmaath, M Magnon, A Mallot, GK Martin, A Matsuda, T Mayes, B McCarthy, JS Medved, K Meyer, W van Middelkoop, G Miller, D Miyachi, Y Mori, K Nassalski, J Niinikoski, TO Oberski, JEJ Ogawa, A Parks, DP da Costa, HP Perrot-Kunne, F Peshekhonov, D Pinsky, L Platchkov, S Plo, M Pluckthun, M Polec, J Pose, D Postma, H Pretz, J Puntaferro, R Radel, G Reicherz, G Rijllart, A Rodriguez, M Rondio, E Sandacz, A Savin, I Schiavon, P Schiller, A Sichtermann, EP Simeoni, F Smirnov, GI Staude, A Steinmetz, A Stiegler, U Stuhrmann, H Tessarotto, F Tlaczala, W Tripet, A Unel, G Velasco, M Vogt, J Voss, R Whitten, C Windmolders, R Wislicki, W Witzmann, A Ylostalo, J Zanetti, AM Zaremba, K CA Spin Muon Collaboration TI Measurement of proton and nitrogen polarization in ammonia and a test of equal spin temperature SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article DE nuclear magnetic resonance; quadrupolar interactions; dynamic nuclear polarization ID STRUCTURE-FUNCTION G(1)(X); INELASTIC MUON SCATTERING; DEUTERON; TARGET; N-14; SMC AB The 1996 data taking of the SMC experiment used polarized protons to measure the spin-dependent structure function g(1) of the proton. Three liters of solid granular ammonia were irradiated at the Bonn electron linac in order to create the paramagnetic radicals which are needed for polarizing the protons. Proton polarizations of +/- (90 +/- 2.5)% were routinely reached. An analysis based on a theoretical line shape for spin-1. systems with large quadrupolar broadening was developed which allowed the nitrogen polarization in the ammonia to be determined with a 10% relative error. The measured quadrupolar coupling constant of N-14 agrees well with earlier extrapolated values. The polarization of the nitrogen nuclei was measured as a function of the proton polarization in order to provide a test of the equal spin temperature (EST) hypothesis. It was found to be closely valid under the dynamic nuclear polarization conditions with which the protons are polarized. Large deviations from EST could be induced by cross relaxing the proton and nitrogen spin systems at low fields. Nitrogen polarizations up to 40% were reached by these means. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Univ Santiago, Dept Particle Phys, Santiago De Compostela 15706, Spain. Istanbul Univ, Istanbul, Turkey. Bogazici Univ, Istanbul, Turkey. Istanbul Tech Univ, TR-80626 Istanbul, Turkey. Univ Uppsala, Dept Radiat Sci, S-75121 Uppsala, Sweden. Soltan Inst Nucl Studies, PL-00681 Warsaw, Poland. Univ Warsaw, PL-00681 Warsaw, Poland. Univ Bielefeld, Dept Phys, D-33501 Bielefeld, Germany. Univ Munich, Dept Phys, D-80799 Munich, Germany. CEA Saclay, DAPNIA, F-91191 Gif Sur Yvette, France. Univ Trieste, I-34127 Trieste, Italy. Ist Nazl Fis Nucl, Dept Phys, I-34127 Trieste, Italy. Ruhr Univ Bochum, Dept Phys, D-44780 Bochum, Germany. Univ Mainz, Inst Nucl Phys, D-55099 Mainz, Germany. Univ Virginia, Dept Phys, Charlottesville, VA 22901 USA. Free Univ Amsterdam, NL-1009 AJ Amsterdam, Netherlands. Delft Univ Technol, NIKHEF, NL-2600 AA Delft, Netherlands. FOM, NL-1098 SJ Amsterdam, Netherlands. Univ Calif Los Angeles, Dept Phys, Los Angeles, CA 90024 USA. Yale Univ, Dept Phys, New Haven, CT 06511 USA. Northwestern Univ, Dept Phys, Evanston, IL 60208 USA. Univ Houston, Dept Phys, Houston, TX 77204 USA. GKSS Forschungszentrum Geesthacht GmbH, D-21494 Geesthacht, Germany. Univ Freiburg, Dept Phys, D-79104 Freiburg, Germany. Nagoya Univ, Dept Phys, Chikusa Ku, Nagoya, Aichi 464, Japan. CIRSE, Chikusa Ku, Nagoya, Aichi 464, Japan. CERN, CH-1211 Geneva 23, Switzerland. JINR, Lab Particle Phys, Dubna, Russia. Helsinki Univ Technol, Low Temp Lab, FIN-02150 Espoo, Finland. Helsinki Univ Technol, Inst Particle Phys, FIN-02150 Espoo, Finland. Tel Aviv Univ, Sch Phys, IL-69978 Tel Aviv, Israel. Univ Mons, Fac Sci, B-7000 Mons, Belgium. Univ Bonn, Inst Phys, D-53115 Bonn, Germany. Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. Miyazaki Univ, Fac Engn, Miyazaki 88921, Japan. Paul Scherrer Inst, CH-5232 Villigen, Switzerland. RIKEN, Inst Phys & Chem Res, Wako, Saitama 35101, Japan. Univ Calif Santa Cruz, Inst Particle Phys, Santa Cruz, CA 95064 USA. Natl Lab High Energy Phys, KEK, Tsukuba, Ibaraki 305, Japan. Warsaw Univ Technol, Inst Radioelect, Warsaw, Poland. Warsaw Univ Technol, Inst Phys, Warsaw, Poland. RP Kyynarainen, J (reprint author), Univ Jyvaskyla, Dept Phys, POB 35, SF-40351 Jyvaskyla, Finland. EM jukka.kyynarainen@phys.jyu.fi RI Adeva, Bernardo /L-1378-2014; de Groot, Nicolo/A-2675-2009; Hautle, Patrick/C-1044-2012; Zanetti, Anna/I-3893-2012; Martin, Anna/I-9381-2012; Le Goff, Jean-Marc/E-7629-2013; Gallas Torreira, Abraham Antonio/K-6508-2014; Plo Casasus, Maximo/M-1445-2014 OI Adeva, Bernardo /0000-0001-9756-3712; Hautle, Patrick/0000-0002-0502-8278; Martin, Anna/0000-0002-1333-0143; Gallas Torreira, Abraham Antonio/0000-0002-2745-7954; Plo Casasus, Maximo/0000-0002-2289-918X NR 42 TC 14 Z9 14 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD DEC 11 PY 1998 VL 419 IS 1 BP 60 EP 82 DI 10.1016/S0168-9002(98)00916-4 PG 23 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 144GX UT WOS:000077306900005 ER PT J AU Sussman, JL AF Sussman, JL TI Protein data bank deposits SO SCIENCE LA English DT Letter C1 Brookhaven Natl Lab, Prot Data Bank, Upton, NY 11973 USA. Weizmann Inst Sci, Dept Biol Struct, IL-76100 Rehovot, Israel. RP Sussman, JL (reprint author), Brookhaven Natl Lab, Prot Data Bank, Upton, NY 11973 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 USA SN 0036-8075 J9 SCIENCE JI Science PD DEC 11 PY 1998 VL 282 IS 5396 BP 1993 EP 1993 PG 1 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 147BB UT WOS:000077467100022 PM 9874649 ER PT J AU Ronning, F Kim, C Feng, DL Marshall, DS Loeser, AG Miller, LL Eckstein, JN Bozovic, I Shen, ZX AF Ronning, F Kim, C Feng, DL Marshall, DS Loeser, AG Miller, LL Eckstein, JN Bozovic, I Shen, ZX TI Photoemission evidence for a remnant fermi surface and a d-wave-like dispersion in insulating Ca2CuO2Cl2 SO SCIENCE LA English DT Article ID T-J MODEL; ANGLE-RESOLVED PHOTOEMISSION; QUASI-PARTICLE DISPERSION; COPPER-OXIDE SR2CUO2CL2; ELECTRONIC-STRUCTURE; QUANTUM ANTIFERROMAGNETS; CUPRATE SUPERCONDUCTORS; C SUPERCONDUCTORS; BAND-STRUCTURE; HUBBARD-MODEL AB An angle-resolved photoemission study is reported on Ca2CUO2Cl2, a parent compound of high-T-c superconductors. Analysis of the electron occupation probability, n(k), from the spectra shows a steep drop in spectral intensity across a contour that is close to the Fermi surface predicted by the band calculation. This analysis reveals a Fermi surface remnant, even though Ca2CuO2Cl2 is a Mott insulator. The Lowest energy peak exhibits a dispersion with approximately the \cosk(x)a - cosk(y)a\ form along this remnant Fermi surface. Together with the data from Dy-doped Bi2Sr2CaCu2O8+delta, these results suggest that this d-wave-like dispersion of the insulator is the underlying reason for the pseudo gap in the underdoped regime. C1 Dept Phys, Stanford, CA 94305 USA. Dept Appl Phys, Stanford, CA 94305 USA. Stanford Synchrotron Radiat Lab, Stanford, CA 94305 USA. Motorola Inc, Phoenix Corp Res Lab, Tempe, AZ 85284 USA. Iowa State Univ, Dept Phys, Ames, IA 50011 USA. Varian Associates Inc, Ginzton Res Ctr, Palo Alto, CA 94304 USA. RP Shen, ZX (reprint author), Dept Phys, Stanford, CA 94305 USA. EM shen@ee.stanford.edu NR 57 TC 226 Z9 227 U1 0 U2 14 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 USA SN 0036-8075 J9 SCIENCE JI Science PD DEC 11 PY 1998 VL 282 IS 5396 BP 2067 EP 2072 DI 10.1126/science.282.5396.2067 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 147BB UT WOS:000077467100043 ER PT J AU Aruguete, DM Aldstadt, JH Mueller, GM AF Aruguete, DM Aldstadt, JH Mueller, GM TI Accumulation of several heavy metals and lanthanides in mushrooms (Agaricales) from the Chicago region SO SCIENCE OF THE TOTAL ENVIRONMENT LA English DT Article DE Amanita flavorubescens; Amanita rubescens; Russula pectinatoides; lanthanides; silver; cadmium; barium; lead; ectomycorrhizae; heavy metal accumulation ID TRACE-METALS; FUNGI; MERCURY; RADIOCESIUM; TOLERANCE; TOXICITY; BINDING; CADMIUM; SILVER; FOREST AB This study explored the differences in metal uptake in sporocarps of ectomycorrhizae-forming fungi relative to (1) fungal species; (2) collection location; (3) differential metal uptake and variation within single-species, single-area populations; and (4) mobile metal content of soil substrate for the fungi. In addition, this study examined levels of some of the lanthanides in these mushrooms, as lanthanide uptake in higher fungi has not been quantified to date. In 1995 and 1996, sporocarps from three species of ectomycorrhizal fungi (Amanita flavorubescens, Amanita rubescens, and Russula pectinatoides) were collected from Cowles Bog, Indiana Dunes National Lakeshore (near an industrial area) and the Palos forest preserves (near a residential area). Soil was also collected from the Cowles Bog plots; metals were extracted from the soil, either with local Lake Michigan water or with nitric acid. These two extractions were meant to simulate the natural soil equilibrium concentrations of soluble metals and the maximum possible effects of any fungal chelating chemicals, respectively. An inductively coupled plasma mass spectrometer was used to analyze soil extracts and nitric acid digests of whole sporocarps for the target analytes. The metals found at elevated levels in the mushrooms included four of environmental interest (Ag, Cd, Ba, and Pb) and three lanthanides (La, Ce, and Nd). Significant differences in uptake of metals were observed between A. rubescens and R. pectinatoides, while A. rubescens and A. flavorubescens were not significantly different. With regard to location, more cadmium was found in Cowles Bog collections of A. rubescens, while Pales forest A. rubescens had more of the lanthanides and barium. Significant specimen-to-specimen variation occurred in all populations examined. Correlation analysis between pairs of trace elements within each sporocarp population revealed strong positive correlations between the lanthanides. Sporocarps concentrated more metal than was made available by the lake water extraction of soil and less metal than was made available by the nitric acid extraction of soil. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Field Museum Nat Hist, Dept Bot, Chicago, IL 60605 USA. Univ Chicago, Div Phys Sci, Chicago, IL 60637 USA. Argonne Natl Lab, Div Environm Res, Argonne, IL 60439 USA. RP Mueller, GM (reprint author), Field Museum Nat Hist, Dept Bot, Chicago, IL 60605 USA. NR 62 TC 35 Z9 39 U1 2 U2 18 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0048-9697 J9 SCI TOTAL ENVIRON JI Sci. Total Environ. PD DEC 11 PY 1998 VL 224 IS 1-3 BP 43 EP 56 DI 10.1016/S0048-9697(98)00319-2 PG 14 WC Environmental Sciences SC Environmental Sciences & Ecology GA 160MG UT WOS:000078234000005 ER PT J AU Johnson, CH Richter, SK Hamilton, CH Hoyt, JJ AF Johnson, CH Richter, SK Hamilton, CH Hoyt, JJ TI Static grain growth in a microduplex Ti-6Al-4V alloy SO ACTA MATERIALIA LA English DT Article ID TITANIUM-ALLOYS AB The grain growth behavior of the microduplex titanium, 6% aluminum, 4% vanadium alloy is addressed. Although there has been considerable work done on second phase particle coarsening, there is Limited research on coarsening in a two-phase material with nearly equal phase ratios. In this study, coarsening parameters were determined for the temperature range of 850-925 degrees C, where alpha and beta phase ratios are approximately 50 percent. Experimentally determined grain growth data for the Ti alloy are found to follow classical particle-stabilized grain growth kinetics with a temperature dependent coefficient and a constant exponent. On the basis of these observations a grain boundary pipe diffusion model is proposed which has the desired features of incorporating both the faster kinetics of the grain boundary diffusion and the unidirectional exponent q = 5, which is often observed in microduplex alloys. The model appears to resolve a previously reported dilemma that the time exponent suggests pipe diffusion bur the kinetics associated with the triple boundary is too slow. The concept proposed should have applicability to other two-phase alloys containing approximately equal volume fractions of each phase. (C) 1998 Acta Metallurgica Inc. Published by Elsevier Science Ltd. All rights reserved. C1 Washington State Univ, Sch Mech & Mat Engn, Pullman, WA 99164 USA. Cent Washington Univ, Ind Engn Technol Dept, Ellensburg, WA 98926 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Hamilton, CH (reprint author), Washington State Univ, Sch Mech & Mat Engn, Pullman, WA 99164 USA. NR 19 TC 8 Z9 11 U1 2 U2 13 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1359-6454 J9 ACTA MATER JI Acta Mater. PD DEC 10 PY 1998 VL 47 IS 1 BP 23 EP 29 DI 10.1016/S1359-6454(98)00341-3 PG 7 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 156HR UT WOS:000077996000004 ER PT J AU Ernst, F Recnik, A Langjahr, PA Nellist, PD Ruhle, M AF Ernst, F Recnik, A Langjahr, PA Nellist, PD Ruhle, M TI Atomistic structure of misfit dislocations in SrZrO3/SrTiO3 interfaces SO ACTA MATERIALIA LA English DT Article AB The atomistic structure of misfit dislocations at heterointerfaces between two ionic crystals with the perovskite structure, SrZrO3 and SrTiO3, is investigated. The interfaces were fabricated by metal-organic deposition of SrZrO3 layers on (001) SiTiO3 single crystal substrates. Under appropriate conditions the SrZrO3 layer grows epitaxially, with its crystal lattice parallel to the lattice of the substrate ("cube-on-cube" orientation relationship). In the layer/substrate interface a square network of dislocations accommodates the misfit between corresponding spacings in the two crystals. These misfit dislocations have edge character, (010) line directions, and (100) Burgers vectors parallel to the interface. The SrZrO3/SrTiO3 interface has been imaged with the misfit dislocations in end-on projection by high-resolution transmission electron microscopy and also by high-resolution scanning transmission electron microscopy. Quantitative image analysis has shown that a (002) layer of TiO2 terminates the SrTiO3 crystal, and the SrZrO3 crystal commences with a (002) layer of Sr-O. Concerning the {200} layers normal to the interface it was found that in interface regions of good match, between the misfit dislocations, the perovskite structure continues straight through the interface: Sr-O layers of SrTiO3 continue as Sr-O layers of SrZrO3; and TiO2 layers continue as ZrO2 layers. Where the misfit dislocations reside, however, in regions of poor match, a lateral offset exists between the two crystals and disrupts the perovskite structure: on the core plane (the symmetry plane) of the misfit dislocations a (200) TiO2 layer of SrTiO3 continues as a (200) SrO layer in SrZrO3. (C) 1998 Acta Metallurgica Inc. Published by Elsevier Science Ltd. All rights reserved. C1 Max Planck Inst Met Forsch, D-70193 Stuttgart, Germany. Jozef Stefan Inst, Dept Ceram, Ljubljana 1000, Slovenia. Univ Karlsruhe, Inst Keram Maschinenbau, D-76131 Karlsruhe, Germany. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Univ Birmingham, Sch Phys & Astron, Nanoscale Phys Res Lab, Birmingham B15 2TT, W Midlands, England. RP Ernst, F (reprint author), Max Planck Inst Met Forsch, Seestr 92, D-70193 Stuttgart, Germany. RI Ernst, Frank/J-4016-2013 NR 21 TC 19 Z9 19 U1 2 U2 19 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1359-6454 J9 ACTA MATER JI Acta Mater. PD DEC 10 PY 1998 VL 47 IS 1 BP 183 EP 198 DI 10.1016/S1359-6454(98)00334-6 PG 16 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 156HR UT WOS:000077996000019 ER PT J AU Hoyt, JJ AF Hoyt, JJ TI Coarsening in multiphase multicomponent systems - I. The mean field limit SO ACTA MATERIALIA LA English DT Article ID ALLOYS AB Ostwald ripening in multicomponent systems where an arbitrary number of precipitate phases are coarsening is examined. Within the mean field approximation it is found that the coarsening rate constant for each phase is identical to the previously derived result for a single phase growing in a multicomponent system. Also, the late time particle size distribution for each phase, when normalized by its average radius, is equivalent to the distribution predicted by Lifschitz and Slyozov. Finally, the decay rate of each of the supersaturation terms is derived. (C) 1998 Acta Metallurgica Inc. Published by Elsevier Science Ltd. All rights reserved. C1 Sandia Natl Labs, Computat Mat Sci Dept, Livermore, CA 94551 USA. RP Hoyt, JJ (reprint author), Sandia Natl Labs, Computat Mat Sci Dept, Livermore, CA 94551 USA. NR 11 TC 6 Z9 6 U1 0 U2 2 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1359-6454 J9 ACTA MATER JI Acta Mater. PD DEC 10 PY 1998 VL 47 IS 1 BP 345 EP 351 DI 10.1016/S1359-6454(98)00316-4 PG 7 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 156HR UT WOS:000077996000033 ER PT J AU Tikare, V Holm, EA Fan, D Chen, LQ AF Tikare, V Holm, EA Fan, D Chen, LQ TI Comparison of phase-field and Potts models for coarsening processes SO ACTA MATERIALIA LA English DT Article ID COMPUTER-SIMULATION; GRAIN-GROWTH; EVOLUTION; KINETICS; TRANSFORMATION; DYNAMICS; ZIRCONIA; SYSTEM AB We have compared the phase-field model to the Potts model for two coarsening processes, grain growth and Ostwald ripening, both in two-dimensions. The Potts model is a discrete, statistical mechanical numerical simulation technique. In contrast, the phase-field model is a continuum, thermodynamic numerical simulation technique. The similarities and differences in microstructures, kinetics, and grain size distributions obtained for grain growth and Ostwald ripening by the phase-field model and by the Potts model were investigated. Both models gave very similar kinetic, topological and grain size distribution results for grain growth and Ostwald ripening in spite of their different approaches. In this paper, we review each model and its application to coarsening processes, present the results of grain growth and Ostwald ripening and finally, discuss how the physics of grain growth and Ostwald ripening is incorporated into these two different models. (C) 1998 Acta Metallurgica Inc. Published by Elsevier Science Ltd. All rights reserved. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Penn State Univ, University Pk, PA 16802 USA. RP Tikare, V (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. RI Chen, LongQing/I-7536-2012; Holm, Elizabeth/S-2612-2016 OI Chen, LongQing/0000-0003-3359-3781; Holm, Elizabeth/0000-0003-3064-5769 NR 31 TC 29 Z9 29 U1 2 U2 16 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1359-6454 J9 ACTA MATER JI Acta Mater. PD DEC 10 PY 1998 VL 47 IS 1 BP 363 EP 371 DI 10.1016/S1359-6454(98)00313-9 PG 9 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 156HR UT WOS:000077996000035 ER PT J AU Stancil, PC Lepp, S Dalgarno, A AF Stancil, PC Lepp, S Dalgarno, A TI The deuterium chemistry of the early universe SO ASTROPHYSICAL JOURNAL LA English DT Article DE cosmic microwave background; early universe; molecular processes; nuclear reactions, nucleosynthesis, abundances ID INTERSTELLAR MOLECULAR SHOCKS; NONRADIATIVE CHARGE-TRANSFER; RADIATIVE ASSOCIATION; DISSOCIATIVE RECOMBINATION; HYDROGEN PLASMAS; BARYON DENSITY; CROSS-SECTIONS; AB-INITIO; CLOUDS; FRACTIONATION AB The chemistry of deuterium, as well as that of hydrogen and helium, in the postrecombination era of the expanding early universe is presented. A thorough survey of all potentially important gas-phase reactions involving the primordial elements produced in the Big Bang, with a particular emphasis on deuterium, is given. The reaction set, consisting of 144 processes, is used in a nonequilibrium chemistry model to follow the production of primordial molecules in the postrecombination era. It is found that significant deuterium fractionation occurs for HD+, HD, and H2D+, while the abundance of D+ is reduced compared to the proton abundance. Even with the enhanced fractionation of H2D+, its abundance is predicted to be too small to cause any interesting cosmological consequences, such as possible attenuation of spatial anisotropies in the cosmic background radiation held, detections of the epochs of reionization and reheating, or constraints on the primordial deuterium abundance. HD, being the second most abundant primordial molecule after H-2, may play a role in subsequent structure formation because of its cooling radiation. C1 Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. Univ Nevada, Dept Phys, WM Keck Lab Computat Phys, Las Vegas, NV 89154 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Oak Ridge Natl Lab, Div Phys, POB 2008, Oak Ridge, TN 37831 USA. EM stancil@mail.phy.ornl.gov; lepp@physics.univ.edu; sdalgarno@cfa.harvard.edu NR 73 TC 166 Z9 166 U1 1 U2 7 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X EI 1538-4357 J9 ASTROPHYS J JI Astrophys. J. PD DEC 10 PY 1998 VL 509 IS 1 BP 1 EP 10 DI 10.1086/306473 PN 1 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 178DE UT WOS:000079250400001 ER PT J AU Bhat, PC Prosper, HB Snyder, SS AF Bhat, PC Prosper, HB Snyder, SS TI Top quark physics at the Tevatron SO INTERNATIONAL JOURNAL OF MODERN PHYSICS A LA English DT Review ID PRODUCTION CROSS-SECTION; CHARGED-HIGGS-BOSON; = 1.8 TEV; PROTON-ANTIPROTON COLLISIONS; CHANGING NEUTRAL CURRENTS; HEAVY-PARTICLE-PRODUCTION; HADRON HADRON-COLLISIONS; SILICON VERTEX DETECTOR; CERN PPBAR COLLIDER; E+E ANNIHILATION AB The discovery of the top quark in 1995, by the CDF and DO collaborations at the Fermilab Tevatron, marked the dawn of a new era in particle physics. Since then, enormous efforts have been made to study the properties of this remarkable particle, especially its mass and production cross section. In this article, we review the status of top quark physics as studied by the two collaborations using the p (p) over bar collider data at root s = 1.8 TeV. The combined measurement of the top quark mass, m(t) = 173.8 +/- 5.0 GeV/c(2), makes it known to a fractional precision better than any other quark mass. The production cross sections are measured as sigma(t (t) over bar) = 7.6(-1.5)(+1.8) pb by CDF and sigma(t (t) over bar) = 5.5 +/- 1.8 pb by DO. Further investigations of t (t) over bar decays and future prospects are briefly discussed. C1 Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Florida State Univ, Dept Phys, Tallahassee, FL 32306 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. RP Fermilab Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. NR 216 TC 34 Z9 34 U1 0 U2 3 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA 5 TOH TUCK LINK, SINGAPORE 596224, SINGAPORE SN 0217-751X EI 1793-656X J9 INT J MOD PHYS A JI Int. J. Mod. Phys. A PD DEC 10 PY 1998 VL 13 IS 30 BP 5113 EP 5218 DI 10.1142/S0217751X98002389 PG 106 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 147LE UT WOS:000077568800001 ER PT J AU Dawkins, PT Dunbar, SR Douglass, RW AF Dawkins, PT Dunbar, SR Douglass, RW TI The origin and nature of spurious eigenvalues in the spectral tau method SO JOURNAL OF COMPUTATIONAL PHYSICS LA English DT Article DE spectral methods; Chebyshev-tau method; spurious eigenvalues; generalized eigenvalue problems ID STABILITY; CHEBYSHEV; ACCURATE AB The Chebyshev-tau spectral method for approximating eigenvalues of boundary value problems may produce spurious eigenvalues with large positive real parts, even when all true eigenvalues of the problem are known to have negative real parts. We explain the origin and nature of the "spurious eigenvalues" in an example problem. The explanation will demonstrate that the large positive eigenvalues are an approximation of infinite eigenvalues in a nearby generalized eigenvalue problem. (C) 1998 Academic Press. C1 Univ Nebraska, Dept Math & Stat, Lincoln, NE 68588 USA. Lamar Univ, Dept Math, Beaumont, TX 77710 USA. Idaho Natl Engn Lab, Idaho Falls, ID 83415 USA. RP Dunbar, SR (reprint author), Univ Nebraska, Dept Math & Stat, Lincoln, NE 68588 USA. EM pdawkins@math.unl.edu; sdunbar@math.unl.edu; rxd@inel.gov NR 25 TC 14 Z9 14 U1 0 U2 3 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0021-9991 J9 J COMPUT PHYS JI J. Comput. Phys. PD DEC 10 PY 1998 VL 147 IS 2 BP 441 EP 462 DI 10.1006/jcph.1998.6095 PG 22 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA 147YR UT WOS:000077525800009 ER PT J AU Sandrone, G Dixon, DA AF Sandrone, G Dixon, DA TI A periodic density functional theory and Hartree-Fock study of alkali halides with Gaussian orbitals SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID STRUCTURAL-PROPERTIES; WAVE CALCULATIONS; BASIS-SETS; NACL; ABINITIO; SYSTEMS; SODIUM AB Periodic-density functional theory (DFT) and Hartree-Fock calculations have been performed on the alkali halides for the alkali metals Li, Na, K, and Rb and the halogens F, Cl, Br and I. Calculations were done with HF-optimized basis sets and DFT-optimized basis sets, at the HF, local DFT (LDFT), and nonlocal DFT (NLDFT) with the Becke exchange potential and the Perdew-Wang correlation potential. The HF and NLDFT results are similar for the lattice parameters, in general, by overestimating them. The LDFT method always underestimates the lattice parameters. As a consequence, the HF and NLDFT methods predict bulk moduli that are too small and the LDFT method predicts bulk moduli that are too large. The absolute error in the bulk moduli are larger at the LDFT level than at the other levels. Charge distribution maps have been calculated and analyzed. The maps clearly show that the main difference between the HF and DFT densities is in the treatment of exchange and that the nonlocal (gradient) corrections moderate this difference. C1 Pacific NW Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Pacific NW Lab, Environm Mol Sci Lab, POB 999,MS K1-83, Richland, WA 99352 USA. NR 39 TC 9 Z9 9 U1 0 U2 4 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5639 J9 J PHYS CHEM A JI J. Phys. Chem. A PD DEC 10 PY 1998 VL 102 IS 50 BP 10310 EP 10317 DI 10.1021/jp981431v PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 148QP UT WOS:000077543700016 ER PT J AU Whitten, DG Chen, LH Geiger, HC Perlstein, J Song, XD AF Whitten, DG Chen, LH Geiger, HC Perlstein, J Song, XD TI Self-assembly of aromatic-functionalized amphiphiles: The role and consequences of aromatic-aromatic noncovalent interactions in building supramolecular aggregates and novel assemblies SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Review ID LANGMUIR-BLODGETT-FILMS; AIR-WATER-INTERFACE; SURFACTANT TRANS-STILBENES; DOUBLE-MUTANT CYCLES; PI-PI INTERACTIONS; TO-FACE; ORGANIZED ASSEMBLIES; SOLID-STATE; MICROHETEROGENEOUS MEDIA; PHOTOCHEMICAL-REACTIONS AB This feature article presents an overview of a study of several different aromatic-functionalized amphiphiles-fatty acid and phospholipid derivatives. These amphiphiles form organized assemblies when the fatty acids are spread as monolayers at the air-water interface or when the phospholipids are dispersed in aqueous solutions. For a wide range of aromatic chromophores-trans-stilbene derivatives and a series of "vinylogues" (1,4-diphenyl-1,3-butadiene and 1,6-diphenyl-1,3,5-hexatriene), diphenylacetylenes, and azobenzenes such as phenyl, biphenyl, and terphenyl derivatives and modified stilbenes (styryl thiophenes and styryl naphthalenes)-assembly formation is accompanied by formation of aggregates of the aromatic groups. Results of experimental studies and simulations indicate that in many cases the aromatics form a small, stable "unit aggregate" characterized by strong "noncovalent" edge-to-face interactions among adjacent aromatics. Although the unit aggregates exhibit characteristic spectral shifts and strong induced circular dichroism indicating a chiral "pinwheel" aggregate structure, they may be packed together in pure films or dispersions to form an extended glide or herringbone structure. Although the "pinwheel" unit aggregate and the extended glide structure is favored for the majority of aromatics studied, for certain aromatics (styrenes, styrylthiophenes, and alpha-styrylnaphthalenes) a translation layer, characterized by face-to-face noncovalent interactions, is preferred. The glide or herringbone aggregates are readily distinguished from the translation aggregates by different spectral signatures and different photochemical and photophysical behavior. Factors controlling the type of aggregate and hence extended structure formed from different aromatic functionalized aromatics include shape and steric factors and strength of the competing noncovalent edge-face and face-face interactions. C1 Los Alamos Natl Lab, Div Chem Sci & Technol, Los Alamos, NM 87545 USA. Univ Rochester, Dept Chem, Ctr Photoinduced Charge Transfer, Rochester, NY 14627 USA. RP Los Alamos Natl Lab, Div Chem Sci & Technol, POB 1663, Los Alamos, NM 87545 USA. NR 95 TC 92 Z9 94 U1 2 U2 35 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1520-6106 J9 J PHYS CHEM B JI J. Phys. Chem. B PD DEC 10 PY 1998 VL 102 IS 50 BP 10098 EP 10111 DI 10.1021/jp9824656 PG 14 WC Chemistry, Physical SC Chemistry GA 148QM UT WOS:000077543500004 ER PT J AU Sachleben, JR Colvin, V Emsley, L Wooten, EW Alivisatos, AP AF Sachleben, JR Colvin, V Emsley, L Wooten, EW Alivisatos, AP TI Solution-state NMR studies of the surface structure and dynamics of semiconductor nanocrystals SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID NUCLEAR-MAGNETIC-RESONANCE; POLARIZATION TRANSFER; CDSE NANOCRYSTALS; SPECTROSCOPY; ENHANCEMENT; DEPENDENCE; MOLECULES; CLUSTERS; LATTICE AB H-1 and C-13 nuclear magnetic resonance (NMR) relaxation studies of thiophenol-capped CdS nanocrystals are presented. The transverse and longitudinal relaxation times were investigated as a function of nanocrystal radius, and the transverse relaxation time was also studied as a function of temperature. Both proton and carbon T-2 values were found to increase with nanocrystal radius, contrary to initial expectations. This effect is explained in terms of motion of the thiophenol with respect to the nanocrystalline surface. Theoretical expressions for relaxation due to anisotropic motion are developed based on both bridging and terminal bonding configurations of the thiophenol ligands, and the data are fit to these models. The data are found to be consistent with thiophenol ligands bound in a terminal fashion to a single Cd atom. The temperature dependence of the proton T-2 value is also suprising. T-2 is found to decrease with increasing temperature, and the size of this change scales with the nanocrystal radius. This is explained in terms of an extra component of relaxation due to thermally excited electrons. C1 Ohio State Univ, Johnston Lab 119, Columbus, OH 43210 USA. Rice Univ, Dept Chem, Houston, TX 77005 USA. Ecole Normale Super Lyon, CNRS, Lab Stereochim & Interact Mol, UMR 117, F-69364 Lyon, France. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. RP Sachleben, JR (reprint author), Ohio State Univ, Johnston Lab 119, Campus Chem Instrument Ctr,176 W 18th Ave, Columbus, OH 43210 USA. RI Emsley, Lyndon/C-6108-2008; Alivisatos , Paul /N-8863-2015 OI Emsley, Lyndon/0000-0003-1360-2572; Alivisatos , Paul /0000-0001-6895-9048 NR 45 TC 53 Z9 53 U1 0 U2 15 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5647 J9 J PHYS CHEM B JI J. Phys. Chem. B PD DEC 10 PY 1998 VL 102 IS 50 BP 10117 EP 10128 DI 10.1021/jp9820121 PG 12 WC Chemistry, Physical SC Chemistry GA 148QM UT WOS:000077543500006 ER PT J AU Gee, B Horne, CR Cairns, EJ Reimer, JA AF Gee, B Horne, CR Cairns, EJ Reimer, JA TI Supertransferred hyperfine fields at Li-7: Variable temperature Li-7 NMR studies of LiMn2O4-based spinels SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID STRUCTURAL PHASE-TRANSITION; LITHIUM BATTERIES; MAGNETIC-PROPERTIES; CATHODE MATERIALS; INSERTION; OXIDES; SPECTROSCOPY; ELECTRODES AB The temperature dependence of the Li-7 NMR shift was measured for LiMn2O4, LiMn2-yNiyO4 (y = 0.1, 0.25, 0.33), LiMn2-yCoyO4 (y = 0.25, 0.5, 1.0), Li[Mn2-yLiy]O-4 (y = 0.1, 0.33), and lambda-MnO2 spinel oxides. The Li-7 NMR shift can be separated into temperature-independent and -dependent components. The temperature-dependent shift follows the Curie-Weiss behavior of the bulk magnetic susceptibility. The temperature-independent shift is attributed to contributions from van Vleck and diamagnetic susceptibilities. Pauli susceptibility may also contribute to the temperature-independent shift in the nickel- and cobalt-substituted spinels. Supertransferred hyperfine (STH) coupling constants were derived from the 7Li NMR shifts and bulk magnetic susceptibility data. The progressive increase in average nominal manganese oxidation state from +3.5 to +4 results in an increase in the supertransferred hyperfine field at the Li-7 nucleus in the lithium-substituted samples. Replacement of manganese by either cobalt or nickel also results in a larger STH field at the Li-7 nuclei. The increase in STH field for the lithium-, nickel-, and cobalt-substituted spinel oxides may arise from a greater covalence in these materials relative to the parent LiMn2O4 spinel oxide. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Environm Energy Technol Div, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Chem Engn & Mat Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Mineral Engn, Berkeley, CA 94720 USA. RP Reimer, JA (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Environm Energy Technol Div, Berkeley, CA 94720 USA. RI Cairns, Elton/E-8873-2012 OI Cairns, Elton/0000-0002-1179-7591 NR 43 TC 64 Z9 65 U1 1 U2 22 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5647 J9 J PHYS CHEM B JI J. Phys. Chem. B PD DEC 10 PY 1998 VL 102 IS 50 BP 10142 EP 10149 DI 10.1021/jp982301p PG 8 WC Chemistry, Physical SC Chemistry GA 148QM UT WOS:000077543500009 ER PT J AU Kane, SM Huntley, DR Gland, JL AF Kane, SM Huntley, DR Gland, JL TI Benzenethiol reaction on the clean and hydrogen pretreated Ni(100) surface SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID NI(111) SURFACE; VIBRATIONAL EELS; HYDRODESULFURIZATION; ADSORPTION; SPECTROSCOPY; PT(111); DESULFURIZATION; METHANETHIOL; THIOPHENOL; MECHANISM AB Benzenethiol reactions on clean and hydrogen precovered Ni(100) surfaces have been studied in order to characterize C-S bond breaking. Benzenethiol adsorbs at 90 K as phenylthiolate and surface hydrogen. The dominant benzene formation pathway for large coverages of benzenethiol occurs at 270 K. C-S bond breaking involves direct reaction of phenylthiolate with the nickel surface; hydrogen does not appear to be directly involved. The rate-limiting C-S bond breaking step is followed by rapid hydrogenation of adsorbed phenyl to form benzene which desorbs from the sulfur covered surface. Deuterium incorporation studies support this mechanism since single hydrogen addition dominates as expected for hydrogenation of an adsorbed phenyl intermediate. For the benzenethiol saturated surface (0.30 monolayer), hydrogen preadsorption increases the temperature for benzene formation by up to 20 K and increases the benzene yield up to 37%. Reorientation of the phenylthiolate away from the surface in the presence of large coadsorbed hydrogen coverages is indicated by vibrational characterization. This hydrogen induced reorientation appears to be associated with the increase in C-S bond activation energy. Above 500 K dehydrogenation of adsorbed phenylthiolate derived species results in formation of surface bound polyaromatic hydrocarbons (PAHs) coadsorbed with sulfur; the hydrogen formed in this process desorbs. For low coverages of benzenethiol, no 270 K benzene is observed due to increased dehydrogenation by the surface. A small amount of benzene is formed by disproportionation above the temperature of free hydrogen desorption (400 K). A comparison of benzenethiol reactions on the three low Miller index surfaces of nickel clearly indicates that hydrogen availability at reaction temperature has a large influence on benzene formation. Hydrogen desorption prior to C-S bond activation on the Ni(100) surface limits benzene formation, while substantial hydrogen availability on the Ni(111) and Ni(110) surfaces facilitates benzene formation. C1 Univ Michigan, Dept Chem, Ann Arbor, MI 48109 USA. Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Gland, JL (reprint author), Univ Michigan, Dept Chem, Ann Arbor, MI 48109 USA. NR 24 TC 8 Z9 8 U1 2 U2 4 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5647 J9 J PHYS CHEM B JI J. Phys. Chem. B PD DEC 10 PY 1998 VL 102 IS 50 BP 10216 EP 10222 DI 10.1021/jp981172+ PG 7 WC Chemistry, Physical SC Chemistry GA 148QM UT WOS:000077543500020 ER PT J AU Ying, LM Xie, XS AF Ying, LM Xie, XS TI Fluorescence spectroscopy, exciton dynamics, and photochemistry of single allophycocyanin trimers SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID ENERGY-TRANSFER; ROOM-TEMPERATURE; OPTICAL MICROSCOPY; MOLECULE DYNAMICS; STATE RELAXATION; CHROMOPHORE; KINETICS; PHOTOPHYSICS; EXCITATION AB We report a study of the allophycocyanin trimer (APC), a light-harvesting protein complex from cyanobacteria, by room-temperature single-molecule measurements of fluorescence spectra, lifetimes, intensity trajectories, and polarization modulation. Emission spectra of individual APC trimers are found to be homogeneous on the time scale of seconds. In contrast, their emission lifetimes are found to be widely distributed because of generation of long-lived exciton traps during the course of measurements. The intensity trajectories and polarization modulation experiments indicate reversible exciton trap formation within the three quasi-independent pairs of strong interacting alpha 84 and beta 84 chromophores in APC, as well as photobleaching of individual chromophores. Comparison experiments under continuous-wave and pulsed excitation reveal a two-photon mechanism for generating exciton traps and/or photobleaching, which involves exciton-exciton annihilation. These single-molecule experiments provide new insights into the spectroscopy, exciton dynamics, and photochemistry of light-harvesting complexes. C1 Pacific NW Lab, William R Wiley Environm Mol Sci Lab, Richland, WA 99352 USA. RP Xie, XS (reprint author), Pacific NW Lab, William R Wiley Environm Mol Sci Lab, POB 999,K8-88, Richland, WA 99352 USA. RI Ying, Liming/G-7999-2011 OI Ying, Liming/0000-0001-9752-6292 NR 48 TC 114 Z9 116 U1 0 U2 16 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5647 J9 J PHYS CHEM B JI J. Phys. Chem. B PD DEC 10 PY 1998 VL 102 IS 50 BP 10399 EP 10409 DI 10.1021/jp983227d PG 11 WC Chemistry, Physical SC Chemistry GA 148QM UT WOS:000077543500044 ER PT J AU Ernst, M Meier, BH Tomaselli, M Pines, A AF Ernst, M Meier, BH Tomaselli, M Pines, A TI Time reversal of cross-polarization in solid-state NMR SO MOLECULAR PHYSICS LA English DT Article ID NUCLEAR-MAGNETIC-RESONANCE; DYNAMICS; ECHOES AB Cross-polarization at the Hartmann-Hahn condition in solid-state NMR frequently is described in terms of thermodynamics. Spin temperatures characterizing the canonical density operator are assigned to the Zeeman reservoirs of the two spins and the cross-polarization process brings about a state of equilibrium of the two reservoirs with a common temperature. In such a model, cross-polarization from an initially polarized spin species (I spins) to another spin species (S spins) is inherently an irreversible process accompanied by an increase in the entropy of the system. However, a cross-polarization echo can be generated whereby the polarization transferred to the S spins returns to the I spins, restoring the initial density operator. Therefore a thermodynamic description should be applied with care even in samples where the build-up and the decay of the magnetization can be approximated well by multiexponential processes. Such cross-polarization echoes are formed by the consecutive application of two pulse trains that produce effective Hamiltonians differing in sign. The 'time reversal' of cross-polarization is consistent with both the increase in Zeeman entropy during the approach to equilibrium and with the constraint of unitary quantum evolution. C1 Univ Nijmegen, NSR, Ctr Mol Struct Design & Synth, Phys Chem Lab, NL-6525 ED Nijmegen, Netherlands. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. RP Ernst, M (reprint author), ETH Zentrum, Phys Chem Lab, CH-8092 Zurich, Switzerland. RI Ernst, Matthias/A-6732-2010; Meier, Beat/K-4066-2016 OI Ernst, Matthias/0000-0002-9538-6086; Meier, Beat/0000-0002-9107-4464 NR 21 TC 4 Z9 4 U1 0 U2 7 PU TAYLOR & FRANCIS LTD PI LONDON PA ONE GUNPOWDER SQUARE, LONDON EC4A 3DE, ENGLAND SN 0026-8976 J9 MOL PHYS JI Mol. Phys. PD DEC 10 PY 1998 VL 95 IS 5 BP 849 EP 858 DI 10.1080/002689798166477 PG 10 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 146XY UT WOS:000077460200014 ER PT J AU Gregg, MD West, MJ AF Gregg, MD West, MJ TI Galaxy disruption as the origin of intracluster light in the Coma cluster of galaxies SO NATURE LA English DT Article ID EVOLUTION; LUMINOSITY AB Although the existence of a faint background of starlight in the core of the Coma cluster has been well established(1,2), its origin is uncertain. This vast sea of stars could have formed outside the galaxies, using gas left over from the time of the cluster's birth. Alternatively, it might be the accumulated debris generated by interactions between the galaxies over the lifetime of the cluster(3). Here we report the discovery of three large, low-surface-brightness features in the Coma cluster, the most spectacular of which is a plume-like structure, 130 kpc long, in the cluster's heart. These structures will disperse over the next one to two billion years, thereby enhancing the general background light. If this epoch is typical, we argue that a significant fraction-perhaps even most-of the intracluster light results from a steady accumulation of tidal debris generated during galaxy-galaxy and galaxy-duster interactions. C1 Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. Univ Calif Lawrence Livermore Natl Lab, Inst Geophys & Planetary Phys, Livermore, CA 94550 USA. St Marys Univ, Dept Phys & Astron, Halifax, NS B3H 3C3, Canada. RP Gregg, MD (reprint author), Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. NR 25 TC 109 Z9 110 U1 0 U2 1 PU MACMILLAN MAGAZINES LTD PI LONDON PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW SN 0028-0836 J9 NATURE JI Nature PD DEC 10 PY 1998 VL 396 IS 6711 BP 549 EP 552 DI 10.1038/25078 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 147AY UT WOS:000077466800049 ER PT J AU Love, SP Goff, F Counce, D Siebe, C Delgado, H AF Love, SP Goff, F Counce, D Siebe, C Delgado, H TI Passive infrared spectroscopy of the eruption plume at Popocatepetl volcano, Mexico SO NATURE LA English DT Article ID SPECTRAL RADIOMETER; REMOTE DETECTION; GALERAS-VOLCANO; GAS; SO2; CHEMISTRY; VULCANO; DEATHS; TOOL; HCL AB Volcanic gases provide important insights into deep-Earth processes, and gas composition and flux variations show promise as predictors of eruptive activity(1-3). But data correlating gas composition with eruptions are sparse, largely because such studies have traditionally involved direct sampling inside a volcanic crater-a hazardous operation that has resulted in numerous deaths(4,5). Crater-rim-based spectroscopy(6-9), closed-path spectroscopy of gases sampled from aircraft(10), and time-averaged studies using volatile traps(11-13) allow measurements to be taken from safer distances. But when a full-scale explosive eruption threatens, even these methods become dangerous as the hazard radius expands to many kilometres. Previously, only sulphur dioxide has been reliably measurable at such large distances, using correlation spectroscopy(14). Here we describe techniques that extend the useful range of passive infrared spectroscopy to monitor many gases at distances of over 17 km. We demonstrate the use of these techniques in a high-temporal-resolution study of short-term compositional variations associated with an explosive eruption at Mexico's Popocatepetl volcano on 25-26 February 1997. We observed a steady increase in SiF4/SO2 over several days preceding the eruption, followed by a tenfold decrease in this ratio over a few hours immediately afterwards. C1 Univ Calif Los Alamos Natl Lab, NIS Div, Los Alamos, NM 87545 USA. Univ Calif Los Alamos Natl Lab, EES Div, Los Alamos, NM 87545 USA. Univ Nacl Autonoma Mexico, Inst Geofis, Mexico City 04510, DF, Mexico. RP Love, SP (reprint author), Univ Calif Los Alamos Natl Lab, NIS Div, Los Alamos, NM 87545 USA. EM splove@lanl.gov RI Delgado Granados, Hugo/J-3056-2013; OI Delgado Granados, Hugo/0000-0001-5263-7968; Siebe, Claus/0000-0002-3959-9028 NR 33 TC 71 Z9 72 U1 2 U2 16 PU MACMILLAN MAGAZINES LTD PI LONDON PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW SN 0028-0836 J9 NATURE JI Nature PD DEC 10 PY 1998 VL 396 IS 6711 BP 563 EP 567 DI 10.1038/25109 PG 5 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 147AY UT WOS:000077466800054 ER PT J AU Vance, SE Gyulassy, M Wang, XN AF Vance, SE Gyulassy, M Wang, XN TI Baryon number transport via gluonic junctions SO PHYSICS LETTERS B LA English DT Article ID STRANGENESS ENHANCEMENT; PARTICLE-PRODUCTION; COLLISIONS; MODEL; DYNAMICS; ENERGIES; NUCLEON; STRINGS AB A novel non-perturbative gluon junction mechanism is introduced within the HIJING/B nuclear collision event generator to calculate baryon number transport and hyperon production in pA and AA collisions. This gluonic mechanism can account for the observed large mid-rapidity valence baryon yield in Pb + Pb at 160 AGeV and predicts high initial baryon densities at RHIC. However, the highly enhanced Lambda - <(Lambda)over bar> yield and the baryon transverse momentum flow observed in this reaction can only be partially described. (C) 1998 Published by Elsevier Science B.V. All rights reserved. C1 Columbia Univ, Dept Phys, New York, NY 10027 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. RP Vance, SE (reprint author), Columbia Univ, Dept Phys, 538 W 120th St, New York, NY 10027 USA. OI Wang, Xin-Nian/0000-0002-9734-9967 NR 35 TC 95 Z9 95 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 J9 PHYS LETT B JI Phys. Lett. B PD DEC 10 PY 1998 VL 443 IS 1-4 BP 45 EP 50 DI 10.1016/S0370-2693(98)01338-0 PG 6 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 152EP UT WOS:000077763500008 ER PT J AU Smith, BH Riedinger, LL Jin, HQ Reviol, W Satula, W Galindo-Uribarri, A Sarantites, DG Wilson, JN LaFosse, D Mullins, SM AF Smith, BH Riedinger, LL Jin, HQ Reviol, W Satula, W Galindo-Uribarri, A Sarantites, DG Wilson, JN LaFosse, D Mullins, SM TI Enhanced deformation in light Pr nuclei SO PHYSICS LETTERS B LA English DT Article ID BANDS AB We observe for the first time rotational bands of enhanced deformation (ED) in (127)pr and (128)pr, and suggest that these bands are built upon pi g(9/2) ([404](9/2)) in Pr-127 and on the pi g(9/2)upsilon h(11/2) orbitals in Pr-128. These are the lightest isotopes of Pr for which ED bands have been observed. A contrasting trend in the dynamical moments of inertia (J((2))) versus N is observed at low frequencies for the ''normal-deformed'' pi h(11/2) and "enhanced-deformed'' pi g(9/2) bands of Pr127-131 both experimentally and in self-consistent Woods-Saxon calculations. The trends in J((2)) and beta(2) are correlated with a decreasing probability for pair scattering into the deformation-driving upsilon h(9/2)/f(7/2) ([541]1/2) orbital. (C) 1998 Published by Elsevier Science B.V. All rights reserved. C1 Univ Tennessee, Dept Phys, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. Washington Univ, Dept Chem, St Louis, MO 63130 USA. Australian Natl Univ, Dept Nucl Phys, Canberra, ACT 0200, Australia. RP Smith, BH (reprint author), Univ Tennessee, Dept Phys, Knoxville, TN 37996 USA. NR 16 TC 26 Z9 26 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 J9 PHYS LETT B JI Phys. Lett. B PD DEC 10 PY 1998 VL 443 IS 1-4 BP 89 EP 96 DI 10.1016/S0370-2693(98)01337-9 PG 8 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 152EP UT WOS:000077763500015 ER PT J AU Sasaki, S Miyamura, O AF Sasaki, S Miyamura, O TI Lattice study of U-A(1) anomaly: the role of QCD-monopoles SO PHYSICS LETTERS B LA English DT Article ID GAUGE-THEORY; TOPOLOGICAL EXCITATIONS; ABELIAN GAUGE; U(1) PROBLEM; MONTE-CARLO; INSTANTONS; CONFINEMENT; QUARKS AB We investigate the: role of QCD-monopoles for the U-A(1) anomaly in the maximally abelian gauge within the SU(2) lattice gauge theory. The existence of the strong correlation between instantons and QCD-monopoles in the abelian gauge was already shown by both analytic and numerical works including the Monte Carlo simulation. Their interrelation brings us a conjecture that the presence of QCD-monopoles plays a considerable role on the U-A(1) anomaly. We find an evidence for our conjecture on a determination of the fermionic zero modes of the Dirac operator in both the "monopole removed" gauge configuration and the "photon removed" gauge configuration. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Kyoto Univ, Yukawa Inst Theoret Phys, Kyoto 6068502, Japan. Brookhaven Natl Lab, RIKEN BNL Res Ctr, Upton, NY 11973 USA. Hiroshima Univ, Dept Phys, Higashihiroshima 7390046, Japan. RP Kyoto Univ, Yukawa Inst Theoret Phys, Kyoto 6068502, Japan. EM ssasaki@bnl.gov NR 27 TC 14 Z9 14 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 EI 1873-2445 J9 PHYS LETT B JI Phys. Lett. B PD DEC 10 PY 1998 VL 443 IS 1-4 BP 331 EP 337 DI 10.1016/S0370-2693(98)01318-5 PG 7 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 152EP UT WOS:000077763500050 ER PT J AU Breitweg, J Chekanov, S Derrick, M Krakauer, D Magill, S Musgrave, B Repond, J Stanek, R Yoshida, R Mattingly, MCK Abbiendi, G Anselmo, F Antonioli, P Bari, G Basile, M Bellagamba, L Boscherini, D Bruni, A Bruni, G Romeo, GC Castellini, G Cifarelli, L Cindolo, F Contin, A Coppola, N Corradi, M De Pasquale, S Giusti, P Iacobucci, G Laurenti, C Levi, G Margotti, A Massam, T Nania, R Palmonari, F Pesci, A Polini, A Sartorelli, G Garcia, YZ Zichichi, A Amelung, C Bornheim, A Brock, I Coboken, K Crittenden, J Deffner, R Eckert, M Grothe, M Hartmann, H Heinloth, K Heinz, L Hilger, E Jakob, HP Kappes, A Katz, UF Kerger, R Paul, E Pfeiffer, M Schnurbusch, H Weber, A Wieber, H Bailey, DS Barret, O Cottingham, WN Foster, B Hall-Wilton, R Heath, GP Heath, HF McFall, JD Piccioni, D Scott, J Tapper, RJ Capua, M Mastroberardino, A Schioppa, M Susinno, G Jeoung, HY Kim, JY Lee, JH Lim, IT Ma, KJ Pac, MY Caldwell, A Cartiglia, N Jing, Z Liu, W Mellado, B Parsons, JA Ritz, S Sacchi, R Sampson, S Sciulli, F Zhu, Q Borzemski, P Chwastowski, J Eskreys, A Figiel, J Klimek, K Przybycien, MB Zawiejski, L Adamczyk, L Bednarek, B Jelen, K Kisielewska, D Kowal, AM Kowalski, T Przybycien, M Rulikowska-Zarebska, E Suszycki, L Zajac, J Dulinski, Z Kotanski, A Bauerdick, LAT Behrens, U Beier, H Bienlein, JK Burgard, C Desler, K Drews, G Fricke, U Goebel, F Gottlicher, P Graciani, R Haas, T Hain, W Hartner, GF Hasell, D Hebbel, K Johnson, KF Kasemann, M Koch, W Kootz, U Kowalski, H Lindemann, L Lohr, B Martiinez, M Milewski, J Milite, M Monteiro, T Notz, D Pellegrino, A Pelucchi, F Piotrzkowski, K Rohde, M Roldan, J Ryan, JJ Saull, PRB Savin, AA Schneekloth, U Schwarzer, O Selonke, F Sievers, M Stonjek, S Surrow, B Tassi, E Westphal, D Wolf, G Wollmer, U Youngman, C Zeuner, W Burow, BD Coldewey, C Grabosch, HJ Viani, ALD Meyer, A Monig, K Schlenstedt, S Straub, PB Barbagli, G Gallo, E Pelfer, P Maccarrone, G Votano, L Bamberger, A Eisenhardt, S Markun, P Raach, H Wolfle, S Brook, NH Bussey, PJ Doyle, AT Lee, SW Macdonald, N McCance, GJ Saxon, DH Sinclair, LE Skillicorn, IO Strickland, E Waugh, R Bohnet, I Gendner, N Holm, U Meyer-Larsen, A Salehi, H Wick, K Garfagnini, A Gialas, I Gladilin, LK Kcira, D Klanner, R Lohrmann, E Poelz, G Zetsche, F Bacon, TC Cole, JE Howell, GC Lamberti, L Long, KR Miller, DB Prinias, A Sedgbeer, JK Sideris, D Tapper, AD Walker, R Mallik, T Wang, SM Cloth, P Filges, D Ishii, T Kuze, M Suzuki, I Tokushuku, K Yamada, S Yamauchi, K Yamazaki, Y Ahn, SH An, SH Hong, SJ Lee, SB Nam, SW Park, SK Lim, H Park, IH Son, D Barreiro, F Fernandez, JP Garcia, G Glasman, C Hernandez, JM Labarga, L del Peso, J Puga, J Redondo, I Terron, J Corriveau, F Hanna, DS Hartmann, J Murray, WN Ochs, A Padhi, S Pinciuc, C Riveline, M Stairs, DG St-Laurent, M Tsurugai, T Bashkirov, V Dolgoshein, BA Stifutkin, A Bashindzhagyan, GL Ermolov, PF Golubkov, YA Khein, LA Korotkova, NA Korzhavina, IA Kuzmin, VA Lukina, OY Proskuryakov, AS Shcheglova, LM Solomin, AN Zotkin, SA Bokel, C Botje, M Brummer, N Engelen, J Koffeman, E Kooijman, P van Sighem, A Tiecke, H Tuning, N Verkerke, W Vossebeld, J Wiggers, L de Wolf, E Acosta, D Bylsma, B Durkin, LS Gilmore, J Ginsburg, CM Kim, CL Ling, TY Nylander, P Blaikley, HE Cashmore, RJ Cooper-Sarkar, AM Devenish, RCE Edmonds, JK Grosse-Knetter, J Harnew, N Matsushita, T Noyes, VA Quadt, A Ruske, O Sutton, MR Walczak, R Waters, DS Bertolin, A Brugnera, R Carlin, R Dal Corso, F Dosselli, U Limentani, S Morandin, M Posocco, M Stanco, L Stroili, R Voci, C Iannotti, L Oh, BY Okrasinski, JR Toothacker, WS Whitmore, JJ Iga, Y D'Agostini, G Marini, G Nigro, A Raso, M Cormack, C Hart, JC McCubbin, NA Shah, TP Epperson, D Heusch, C Sadrozinski, HFW Seiden, A Wichmann, R Williams, DC Pavel, N Abramowicz, H Briskin, G Dagan, S Kananov, S Levy, A Abe, T Fusayasu, T Inuzuka, M Nagano, K Umemori, K Yamashita, T Hamatsu, R Hirose, T Homma, K Kitamura, S Nishimura, T Arneodo, M Cirio, R Costa, M Ferrero, MI Maselli, S Monaco, V Peroni, C Petrucci, MC Ruspa, M Solano, A Staiano, A Dardo, M Bailey, DC Fagerstroem, CP Galea, R Koop, T Levman, GM Martin, JF Orr, RS Polenz, S Sabetfakhri, A Simmons, D Butterworth, JM Catterall, CD Hayes, ME Heaphy, EA Jones, TW Lane, JB Wing, M Ciborowski, J Grzelak, G Nowak, RJ Pawlak, JM Pawlak, R Smalska, B Tymieniecka, T Wroblewski, AK Zakrzewski, JA Zarnecki, AF Adamus, M Gadaj, T Deppe, O Eisenberg, Y Hochman, D Karshon, U Badgett, WF Chapin, D Cross, R Foudas, C Mattingly, S Reeder, DD Smith, WH Vaiciulis, A Wildschek, T Wodarczyk, M Deshpande, A Dhawan, S Hughes, VW Bhadra, S Frisken, WR Khakzad, M Menary, S Schmidke, WB AF Breitweg, J Chekanov, S Derrick, M Krakauer, D Magill, S Musgrave, B Repond, J Stanek, R Yoshida, R Mattingly, MCK Abbiendi, G Anselmo, F Antonioli, P Bari, G Basile, M Bellagamba, L Boscherini, D Bruni, A Bruni, G Romeo, GC Castellini, G Cifarelli, L Cindolo, F Contin, A Coppola, N Corradi, M De Pasquale, S Giusti, P Iacobucci, G Laurenti, C Levi, G Margotti, A Massam, T Nania, R Palmonari, F Pesci, A Polini, A Sartorelli, G Garcia, YZ Zichichi, A Amelung, C Bornheim, A Brock, I Coboken, K Crittenden, J Deffner, R Eckert, M Grothe, M Hartmann, H Heinloth, K Heinz, L Hilger, E Jakob, HP Kappes, A Katz, UF Kerger, R Paul, E Pfeiffer, M Schnurbusch, H Weber, A Wieber, H Bailey, DS Barret, O Cottingham, WN Foster, B Hall-Wilton, R Heath, GP Heath, HF McFall, JD Piccioni, D Scott, J Tapper, RJ Capua, M Mastroberardino, A Schioppa, M Susinno, G Jeoung, HY Kim, JY Lee, JH Lim, IT Ma, KJ Pac, MY Caldwell, A Cartiglia, N Jing, Z Liu, W Mellado, B Parsons, JA Ritz, S Sacchi, R Sampson, S Sciulli, F Zhu, Q Borzemski, P Chwastowski, J Eskreys, A Figiel, J Klimek, K Przybycien, MB Zawiejski, L Adamczyk, L Bednarek, B Jelen, K Kisielewska, D Kowal, AM Kowalski, T Przybycien, M Rulikowska-Zarebska, E Suszycki, L Zajac, J Dulinski, Z Kotanski, A Bauerdick, LAT Behrens, U Beier, H Bienlein, JK Burgard, C Desler, K Drews, G Fricke, U Goebel, F Gottlicher, P Graciani, R Haas, T Hain, W Hartner, GF Hasell, D Hebbel, K Johnson, KF Kasemann, M Koch, W Kootz, U Kowalski, H Lindemann, L Lohr, B Martiinez, M Milewski, J Milite, M Monteiro, T Notz, D Pellegrino, A Pelucchi, F Piotrzkowski, K Rohde, M Roldan, J Ryan, JJ Saull, PRB Savin, AA Schneekloth, U Schwarzer, O Selonke, F Sievers, M Stonjek, S Surrow, B Tassi, E Westphal, D Wolf, G Wollmer, U Youngman, C Zeuner, W Burow, BD Coldewey, C Grabosch, HJ Viani, ALD Meyer, A Monig, K Schlenstedt, S Straub, PB Barbagli, G Gallo, E Pelfer, P Maccarrone, G Votano, L Bamberger, A Eisenhardt, S Markun, P Raach, H Wolfle, S Brook, NH Bussey, PJ Doyle, AT Lee, SW Macdonald, N McCance, GJ Saxon, DH Sinclair, LE Skillicorn, IO Strickland, E Waugh, R Bohnet, I Gendner, N Holm, U Meyer-Larsen, A Salehi, H Wick, K Garfagnini, A Gialas, I Gladilin, LK Kcira, D Klanner, R Lohrmann, E Poelz, G Zetsche, F Bacon, TC Cole, JE Howell, GC Lamberti, L Long, KR Miller, DB Prinias, A Sedgbeer, JK Sideris, D Tapper, AD Walker, R Mallik, T Wang, SM Cloth, P Filges, D Ishii, T Kuze, M Suzuki, I Tokushuku, K Yamada, S Yamauchi, K Yamazaki, Y Ahn, SH An, SH Hong, SJ Lee, SB Nam, SW Park, SK Lim, H Park, IH Son, D Barreiro, F Fernandez, JP Garcia, G Glasman, C Hernandez, JM Labarga, L del Peso, J Puga, J Redondo, I Terron, J Corriveau, F Hanna, DS Hartmann, J Murray, WN Ochs, A Padhi, S Pinciuc, C Riveline, M Stairs, DG St-Laurent, M Tsurugai, T Bashkirov, V Dolgoshein, BA Stifutkin, A Bashindzhagyan, GL Ermolov, PF Golubkov, YA Khein, LA Korotkova, NA Korzhavina, IA Kuzmin, VA Lukina, OY Proskuryakov, AS Shcheglova, LM Solomin, AN Zotkin, SA Bokel, C Botje, M Brummer, N Engelen, J Koffeman, E Kooijman, P van Sighem, A Tiecke, H Tuning, N Verkerke, W Vossebeld, J Wiggers, L de Wolf, E Acosta, D Bylsma, B Durkin, LS Gilmore, J Ginsburg, CM Kim, CL Ling, TY Nylander, P Blaikley, HE Cashmore, RJ Cooper-Sarkar, AM Devenish, RCE Edmonds, JK Grosse-Knetter, J Harnew, N Matsushita, T Noyes, VA Quadt, A Ruske, O Sutton, MR Walczak, R Waters, DS Bertolin, A Brugnera, R Carlin, R Dal Corso, F Dosselli, U Limentani, S Morandin, M Posocco, M Stanco, L Stroili, R Voci, C Iannotti, L Oh, BY Okrasinski, JR Toothacker, WS Whitmore, JJ Iga, Y D'Agostini, G Marini, G Nigro, A Raso, M Cormack, C Hart, JC McCubbin, NA Shah, TP Epperson, D Heusch, C Sadrozinski, HFW Seiden, A Wichmann, R Williams, DC Pavel, N Abramowicz, H Briskin, G Dagan, S Kananov, S Levy, A Abe, T Fusayasu, T Inuzuka, M Nagano, K Umemori, K Yamashita, T Hamatsu, R Hirose, T Homma, K Kitamura, S Nishimura, T Arneodo, M Cirio, R Costa, M Ferrero, MI Maselli, S Monaco, V Peroni, C Petrucci, MC Ruspa, M Solano, A Staiano, A Dardo, M Bailey, DC Fagerstroem, CP Galea, R Koop, T Levman, GM Martin, JF Orr, RS Polenz, S Sabetfakhri, A Simmons, D Butterworth, JM Catterall, CD Hayes, ME Heaphy, EA Jones, TW Lane, JB Wing, M Ciborowski, J Grzelak, G Nowak, RJ Pawlak, JM Pawlak, R Smalska, B Tymieniecka, T Wroblewski, AK Zakrzewski, JA Zarnecki, AF Adamus, M Gadaj, T Deppe, O Eisenberg, Y Hochman, D Karshon, U Badgett, WF Chapin, D Cross, R Foudas, C Mattingly, S Reeder, DD Smith, WH Vaiciulis, A Wildschek, T Wodarczyk, M Deshpande, A Dhawan, S Hughes, VW Bhadra, S Frisken, WR Khakzad, M Menary, S Schmidke, WB CA ZEUS Collaboration TI Measurement of three-jet distributions in photoproduction at HERA SO PHYSICS LETTERS B LA English DT Article ID RESOLVED PHOTOPRODUCTION; PARTON DISTRIBUTIONS; HADRON-COLLISIONS; MULTIJET EVENTS; MONTE-CARLO; COLLIDER; 3-JET AB The cross section for the photoproduction of events containing three jets with a three-jet invariant mass of M-3J > 50 GeV has been measured with the ZEUS detector at HERA. The three-jet angular distributions are inconsistent with a uniform population of the available phase space but are well described by parton shower models and O(alpha alpha(s)(2)) pQCD calculations. Comparisons with the parton shower model indicate a strong contribution from initial state radiation as well as a sensitivity to the effects of colour coherence. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Argonne Natl Lab, Argonne, IL 60439 USA. Andrews Univ, Berrien Springs, MI 49104 USA. Univ Bologna, Bologna, Italy. Ist Nazl Fis Nucl, I-40126 Bologna, Italy. Univ Bonn, Inst Phys, D-5300 Bonn, Germany. Univ Bristol, HH Wills Phys Lab, Bristol BS8 1TL, Avon, England. Univ Calabria, Dept Phys, I-87036 Cosenza, Italy. Ist Nazl Fis Nucl, Cosenza, Italy. Chonnam Natl Univ, Kwangju, South Korea. Columbia Univ, Nevis Labs, Irvington, NY USA. Inst Nucl Phys, Krakow, Poland. Acad Min & Met, Fac Phys & Nucl Tech, Krakow, Poland. Jagiellonian Univ, Dept Phys, Krakow, Poland. DESY, D-2000 Hamburg, Germany. DESY, IfH Zeuthen, Zeuthen, Germany. Univ Florence, Florence, Italy. Ist Nazl Fis Nucl, I-50125 Florence, Italy. Ist Nazl Fis Nucl, Lab Nazl Frascati, I-00044 Frascati, Italy. Univ Freiburg, Fak Phys, D-7800 Freiburg, Germany. Univ Glasgow, Dept Phys & Astron, Glasgow, Lanark, Scotland. Univ Hamburg, Inst Expt Phys 1, Hamburg, Germany. Univ Hamburg, Inst Expt Phys 2, D-2000 Hamburg, Germany. Univ London Imperial Coll Sci Technol & Med, High Energy Nucl Phys Grp, London, England. Univ Iowa, Dept Phys & Astron, Iowa City, IA 52242 USA. Forschungszentrum Julich, Inst Kernphys, D-5170 Julich, Germany. KEK, Inst Particle & Nucl Studies, Tsukuba, Ibaraki, Japan. Korea Univ, Seoul 136701, South Korea. Kyungpook Natl Univ, Taegu 702701, South Korea. Univ Autonoma Madrid, Dept Fis Teor, Madrid, Spain. McGill Univ, Dept Phys, Montreal, PQ, Canada. Meiji Gakuin Univ, Fac Gen Educ, Yokohama, Kanagawa, Japan. Moscow Engn Phys Inst, Moscow 115409, Russia. Moscow MV Lomonosov State Univ, Inst Nucl Phys, Moscow, Russia. NIKHEF, NL-1009 DB Amsterdam, Netherlands. Univ Amsterdam, Amsterdam, Netherlands. Ohio State Univ, Dept Phys, Columbus, OH 43210 USA. Univ Oxford, Dept Phys, Oxford, England. Univ Padua, Dipartimento Fis, Padua, Italy. Ist Nazl Fis Nucl, Padua, Italy. Penn State Univ, Dept Phys, University Pk, PA 16802 USA. Polytech Univ, Sagamihara, Kanagawa, Japan. Univ Roma La Sapienza, Dipartimento Fis, I-00185 Rome, Italy. Ist Nazl Fis Nucl, Rome, Italy. Rutherford Appleton Lab, Didcot OX11 0QX, Oxon, England. Univ Calif Santa Cruz, Santa Cruz, CA 95064 USA. Univ Siegen, Fachbereich Phys, D-57068 Siegen, Germany. Tel Aviv Univ, Sch Phys, Raymond & Beverly Sackler Fac Exact Sci, IL-69978 Tel Aviv, Israel. Univ Tokyo, Dept Phys, Tokyo 113, Japan. Tokyo Metropolitan Univ, Dept Phys, Tokyo, Japan. Univ Turin, Dipartimento Fis Sperimentale, Turin, Italy. Ist Nazl Fis Nucl, I-10125 Turin, Italy. Univ Turin, Fac Sci 2, Alessandria, Italy. Ist Nazl Fis Nucl, Alessandria, Italy. Univ Toronto, Dept Phys, Toronto, ON, Canada. UCL, Dept Phys & Astron, London, England. Warsaw Univ, Inst Expt Phys, Warsaw, Poland. Inst Nucl Studies, PL-00681 Warsaw, Poland. Weizmann Inst Sci, Dept Particle Phys, IL-76100 Rehovot, Israel. Univ Wisconsin, Dept Phys, Madison, WI 53706 USA. Yale Univ, Dept Phys, New Haven, CT USA. York Univ, Dept Phys, N York, ON M3J 1P3, Canada. CNR, IROE, I-50127 Florence, Italy. RP Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. RI De Pasquale, Salvatore/B-9165-2008; Morandin, Mauro/A-3308-2016; Wing, Matthew/C-2169-2008; Bashkirov, Vladimir/A-4818-2008; Doyle, Anthony/C-5889-2009; Golubkov, Yury/E-1643-2012; Proskuryakov, Alexander/J-6166-2012; Katz, Uli/E-1925-2013; Wiggers, Leo/B-5218-2015; Hernandez Calama, Jose Maria/H-9127-2015; Tassi, Enrico/K-3958-2015; Gladilin, Leonid/B-5226-2011; Solomin, Anatoly/C-3072-2016; Capua, Marcella/A-8549-2015; OI De Pasquale, Salvatore/0000-0001-9236-0748; Morandin, Mauro/0000-0003-4708-4240; Doyle, Anthony/0000-0001-6322-6195; Katz, Uli/0000-0002-7063-4418; Wiggers, Leo/0000-0003-1060-0520; Hernandez Calama, Jose Maria/0000-0001-6436-7547; Gladilin, Leonid/0000-0001-9422-8636; Castellini, Guido/0000-0002-0177-0643; Kasemann, Matthias/0000-0002-0429-2448; Capua, Marcella/0000-0002-2443-6525; Arneodo, Michele/0000-0002-7790-7132; Abbiendi, Giovanni/0000-0003-4499-7562; Graciani Diaz, Ricardo/0000-0001-7166-5198 NR 22 TC 31 Z9 31 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 EI 1873-2445 J9 PHYS LETT B JI Phys. Lett. B PD DEC 10 PY 1998 VL 443 IS 1-4 BP 394 EP 408 DI 10.1016/S0370-2693(98)01360-4 PG 15 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 152EP UT WOS:000077763500059 ER PT J AU Oden, PI AF Oden, PI TI Gravimetric sensing of metallic deposits using an end-loaded microfabricated beam structure SO SENSORS AND ACTUATORS B-CHEMICAL LA English DT Article ID SCANNING FORCE MICROSCOPY; SURFACE STRESS; CANTILEVERS; MICROCANTILEVERS; BIOSENSOR; SENSORS AB In this communication, the gravimetric sensitivities of two geometrically different microfabricated beam structures are reported. Each was loaded serially with gold followed by chromium metal by vapor depositing through a shadow mask exposing only the end of the structures. The change in fundamental resonance frequency was found to be solely a function of the density of the deposited for deposits less than 50 nm in thickness. Therefore, the change in the resonance frequency of the mechanical beam is solely a function of the end-loaded mass. The gravimetric sensitivities of the fundamental mode of excitation for these structures, measured under ambient excitation conditions, is of the order of 10(3) cm(2) g(-1) while the minimum detectable mass density with this type of structure can be as small as approximately 0.5 ng cm(-2). A theoretical relationship is provided that enables further enhancement of the gravimetric sensitivity of these structures through decreasing the thickness and density of the microsensor. Through establishing a quantitative comparison between these structures and other, more traditional acoustic wave sensors, it will be shown that these micromechanical devices offer potential advantages in environmental monitoring applications. (C) 1998 Elsevier Science S.A. All rights reserved. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Oden, PI (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. NR 35 TC 34 Z9 34 U1 1 U2 2 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0925-4005 J9 SENSOR ACTUAT B-CHEM JI Sens. Actuator B-Chem. PD DEC 10 PY 1998 VL 53 IS 3 BP 191 EP 196 DI 10.1016/S0925-4005(98)00339-6 PG 6 WC Chemistry, Analytical; Electrochemistry; Instruments & Instrumentation SC Chemistry; Electrochemistry; Instruments & Instrumentation GA 189MD UT WOS:000079908100009 ER PT J AU Cotton, FA Daniels, LM Guimet, I Henning, RW Jordan, GT Lin, C Murillo, CA Schultz, AJ AF Cotton, FA Daniels, LM Guimet, I Henning, RW Jordan, GT Lin, C Murillo, CA Schultz, AJ TI Compounds with two metal-metal multiple bonds: New ways of making doublets into cyclic quartets SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID DIMOLYBDENUM COMPOUNDS; RECTANGULAR CLUSTERS; NEUTRON-DIFFRACTION; NIOBIUM COMPLEXES; TRIPLE BONDS; MOLYBDENUM; ENVIRONMENT; HYDROGEN; ALKYNES; DIMERS AB New types of products obtained by combining two dinuclear multiply metal-metal bonded species (doublets) to obtain cyclic tetranuclear products (quartets) are reported. One new type consists of pairs of quadruply bonded Mo-2(4+) units united by two mu-X links (X = H, OH, O) although in the last case oxidation has also occurred so that these are Mo-2(5+) moieties. In these cases, the subunits are Mo-2(DArF)(3). The second new type consists of Mo-2(DArF)(2) subunits linked by four mu-X bridges,where X = Cl, Br, I. The previously known compound Mo4I8(PBu3n)(4) has been shown to differ from all previously known Mo4X8(PR3)(4) molecules (X: = Cl, Br) by retaining two quadruple bonds instead of beings metallacyclobutadiyne, as are the others. C1 Texas A&M Univ, Dept Chem, College Stn, TX 77842 USA. Texas A&M Univ, Mol Struct & Bonding Lab, College Stn, TX 77842 USA. Univ Costa Rica, Dept Chem, San Jose, Costa Rica. Argonne Natl Lab, Intense Pulsed Neutron Source, Argonne, IL 60439 USA. RP Cotton, FA (reprint author), Texas A&M Univ, Dept Chem, POB 30012, College Stn, TX 77842 USA. NR 31 TC 29 Z9 29 U1 1 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0002-7863 J9 J AM CHEM SOC JI J. Am. Chem. Soc. PD DEC 9 PY 1998 VL 120 IS 48 BP 12531 EP 12538 DI 10.1021/ja982425f PG 8 WC Chemistry, Multidisciplinary SC Chemistry GA 146ZM UT WOS:000077463800017 ER PT J AU Jenks, CJ Lograsso, TA Thiel, PA AF Jenks, CJ Lograsso, TA Thiel, PA TI Surface reactivity of a sputter-annealed Al-Pd-Mn quasicrystal SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID METHANOL DECOMPOSITION; CO; ADSORPTION; ALUMINUM; PD(100); AL(111); OXIDATION; KINETICS; AL(100); OXYGEN C1 Iowa State Univ Sci & Technol, Ames Lab, Dept Chem, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Dept Mat Sci, Ames, IA 50011 USA. RP Thiel, PA (reprint author), Iowa State Univ Sci & Technol, Ames Lab, Dept Chem, Ames, IA 50011 USA. NR 28 TC 15 Z9 15 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0002-7863 J9 J AM CHEM SOC JI J. Am. Chem. Soc. PD DEC 9 PY 1998 VL 120 IS 48 BP 12668 EP 12669 DI 10.1021/ja981916x PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA 146ZM UT WOS:000077463800035 ER PT J AU Koeck, PJB Kagawa, HK Ellis, MJ Hebert, H Trent, JD AF Koeck, PJB Kagawa, HK Ellis, MJ Hebert, H Trent, JD TI Two-dimensional crystals of reconstituted beta-subunits of the chaperonin TF55 from Sulfolobus shibatae SO BIOCHIMICA ET BIOPHYSICA ACTA-PROTEIN STRUCTURE AND MOLECULAR ENZYMOLOGY LA English DT Article DE two-dimensional protein crystal; transmission electron microscopy; chaperonin; TF55; archaeon; (Sulfolobus shibatae) ID HEAT-SHOCK PROTEINS; MOLECULAR CHAPERONES; THERMOPHILIC ARCHAEBACTERIUM; THERMOPLASMA-ACIDOPHILUM; THERMOSOME; PROGRAMS; ARCHAEA; ALPHA; CELL AB We have obtained 2-dimensional crystals of the P-subunits of the chaperonin TF55 from Sulfolobus shibatae reconstituted into oligomers in the absence of alpha-subunits. The subunits form rings with 9-fold rotational symmetry which arrange themselves in a trigonal lattice. From electron micrographs of negatively stained specimens we have calculated a projection map in plane group p312 showing the rings in top-view. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Karolinska Inst, Novum, Dept Biosci, S-14157 Huddinge, Sweden. Argonne Natl Lab, Ctr Mechanist Biol & Biotechnol, Argonne, IL 60439 USA. RP Koeck, PJB (reprint author), Karolinska Inst, Novum, Dept Biosci, S-14157 Huddinge, Sweden. NR 28 TC 20 Z9 20 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-4838 J9 BBA-PROTEIN STRUCT M JI Biochim. Biophys. Acta-Protein Struct. Molec. Enzym. PD DEC 8 PY 1998 VL 1429 IS 1 BP 40 EP 44 DI 10.1016/S0167-4838(98)00218-0 PG 5 WC Biochemistry & Molecular Biology; Biophysics SC Biochemistry & Molecular Biology; Biophysics GA 152MT UT WOS:000077781900004 PM 9920382 ER PT J AU Zanni, MT Greenblatt, BJ Neumark, DM AF Zanni, MT Greenblatt, BJ Neumark, DM TI Solvent effects on the vibrational frequency of I-2(-) in size-selected I-2(-)(Ar)(n) and I-2(-)(CO2)(n) clusters SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID MOLECULAR-DYNAMICS SIMULATIONS; FEMTOSECOND PHOTOELECTRON-SPECTROSCOPY; RESOLUTION INFRARED-SPECTROSCOPY; GEMINATE RECOMBINATION DYNAMICS; ROTATIONAL SPECTRA; ARGON MATRICES; PHOTODISSOCIATION; ANION; IONS; I2 AB The vibrational frequency of the I-2(-) chromophore in size-selected I-2(-)(Ar)(n) and I-2(-)(CO2)(n) clusters has been measured to wave-number accuracy. The frequencies are determined by creating a coherent superposition of vibrational levels with a femtosecond laser pulse via a resonance impulsive stimulated Raman scattering process. The resulting wave-packet oscillations are detected with femtosecond photoelectron spectroscopy. Blueshifting of the frequency occurs upon solvation, with larger shifts observed for solvation with CO2. The nature of the shifting is discussed and related to specific cluster geometries. (C) 1998 American Institute of Physics. [S0021-9606(98)02246-6]. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA. RP Zanni, MT (reprint author), Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. EM dan@radon.cchem.berkeley.edu RI Zanni, Martin/K-2707-2013; Neumark, Daniel/B-9551-2009 OI Neumark, Daniel/0000-0002-3762-9473 NR 37 TC 18 Z9 18 U1 0 U2 5 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD DEC 8 PY 1998 VL 109 IS 22 BP 9648 EP 9651 DI 10.1063/1.477631 PG 4 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 143UT UT WOS:000077276000002 ER PT J AU Doktycz, MJ Larimer, FW Pastrnak, M Stevens, A AF Doktycz, MJ Larimer, FW Pastrnak, M Stevens, A TI Comparative analyses of the secondary structures of synthetic and intracellular yeast MFA2 mRNAs SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article ID MESSENGER-RNA; UNTRANSLATED REGION; RIBOSOMAL-RNA; POLY(A) TAIL; TRANSLATION; DEADENYLATION; POLYMERASE; MECHANISM; PROTEIN; BINDING AB The overall folded (global) structure of mRNA may be critical to translation and turnover control mechanisms, but it has received little experimental attention. Presented here is a comparative analysis of the basic features of the global secondary structure of a synthetic mRNA and the same intracellular eukaryotic mRNA by dimethyl sulfate (DMS) structure probing. Synthetic MFA2 mRNA of Saccharomyces cerevisiae first was examined by using both enzymes and chemical reagents to determine single-stranded and hybridized regions; RNAs with and without a poly(A) tail were compared. A folding pattern was obtained with the aid of the MFOLD program package that identified the model that best satisfied the probing data. A long-range structural interaction involving the 5' and 3' untranslated regions and causing a juxtaposition of the ends of the RNA, was examined further by a useful technique involving oligo(dT)-cellulose chromatography and antisense oligonucleotides. DMS chemical probing of A and C nucleotides of intracellular MFA2 mRNA was then done. The modification data support a very similar intracellular structure. When low reactivity of A and C residues is found in the synthetic RNA, approximate to 70% of the same sites are relatively more resistant to DMS modification in vivo, A slightly higher sensitivity to DMS is found in vivo for some of the A and C nucleotides predicted to be hybridized from the synthetic structural model, With this small mRNA, the translation process and mRNA-binding proteins do not block DMS modifications, and all A and C nucleotides are modified the same or more strongly than with the synthetic RNA. C1 Oak Ridge Natl Lab, Div Life Sci, Oak Ridge, TN 37831 USA. RP Stevens, A (reprint author), Oak Ridge Natl Lab, Div Life Sci, Oak Ridge, TN 37831 USA. EM stevensa@bio.ornl.gov RI Doktycz, Mitchel/A-7499-2011 OI Doktycz, Mitchel/0000-0003-4856-8343 NR 26 TC 19 Z9 19 U1 0 U2 0 PU NATL ACAD SCIENCES PI WASHINGTON PA 2101 CONSTITUTION AVE NW, WASHINGTON, DC 20418 USA SN 0027-8424 J9 P NATL ACAD SCI USA JI Proc. Natl. Acad. Sci. U. S. A. PD DEC 8 PY 1998 VL 95 IS 25 BP 14614 EP 14621 DI 10.1073/pnas.95.25.14614 PG 8 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 146NJ UT WOS:000077436700008 PM 9843938 ER PT J AU Lelievre, SA Weaver, VM Nickerson, JA Larabell, CA Bhaumik, A Petersen, OW Bissell, MJ AF Lelievre, SA Weaver, VM Nickerson, JA Larabell, CA Bhaumik, A Petersen, OW Bissell, MJ TI Tissue phenotype depends on reciprocal interactions between the extracellular matrix and the structural organization of the nucleus SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article ID GENE-EXPRESSION; EPITHELIAL-CELLS; PROTEIN; DIFFERENTIATION; TRANSCRIPTION; ASSOCIATION; SNRNPS; GROWTH AB What determines the nuclear organization within a cell and whether this organization itself can impose cellular function within a tissue remains unknown. To explore the relationship between nuclear organization and tissue architecture and function, we used a model of human mammary epithelial cell acinar morphogenesis. When cultured within a reconstituted basement membrane (rBM), HMT-3522 cells form polarized and growth-arrested tissue-like acini with a central lumen and deposit an endogenous BM. We show that rBM-induced morphogenesis is accompanied by relocalization of the nuclear matrix proteins NuMA, splicing factor SRm160, and cell cycle regulator Rb. These proteins had distinct distribution patterns specific for proliferation, growth arrest, and acini formation, whereas the distribution of the nuclear lamina protein, lamin B, remained unchanged. NuMA relocalized to foci, which coalesced into larger assemblies as morphogenesis progressed. Perturbation of histone acetylation in the acini by trichostatin A treatment altered chromatin structure, disrupted NuMA foci, and induced cell proliferation. Moreover, treatment of transiently permeabilized acini with a NuMA antibody led to the disruption of NuMA foci, alteration of histone acetylation, activation of metalloproteases, and breakdown of the endogenous BM. These results experimentally demonstrate a dynamic interaction between the extracellular matrix, nuclear organization, and tissue phenotype. They further show that rather than passively reflecting changes in gene expression, nuclear organization itself can modulate the cellular and tissue phenotype. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, Berkeley, CA 94720 USA. Univ Massachusetts, Sch Med, Worcester, MA 01655 USA. Univ Copenhagen, Panum Inst, DK-2200 Copenhagen, Denmark. RP Bissell, MJ (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, MS 83-101, Berkeley, CA 94720 USA. EM mjbissell@lbl.gov RI Wang, Fei/A-7968-2013 FU NCI NIH HHS [R37 CA064786, CA-64786, R01 CA064786] NR 29 TC 158 Z9 160 U1 0 U2 6 PU NATL ACAD SCIENCES PI WASHINGTON PA 2101 CONSTITUTION AVE NW, WASHINGTON, DC 20418 USA SN 0027-8424 J9 P NATL ACAD SCI USA JI Proc. Natl. Acad. Sci. U. S. A. PD DEC 8 PY 1998 VL 95 IS 25 BP 14711 EP 14716 DI 10.1073/pnas.95.25.14711 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 146NJ UT WOS:000077436700024 PM 9843954 ER PT J AU Wang, F Weaver, VM Petersen, OW Larabell, CA Dedhar, S Briand, P Lupu, R Bissell, MJ AF Wang, F Weaver, VM Petersen, OW Larabell, CA Dedhar, S Briand, P Lupu, R Bissell, MJ TI Reciprocal interactions between beta 1-integrin and epidermal growth factor receptor in three-dimensional basement membrane breast cultures: A different perspective in epithelial biology SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article ID CELL-CYCLE PROGRESSION; FOCAL ADHESION KINASE; GENE-EXPRESSION; PROTEIN-KINASE; SIGNAL-TRANSDUCTION; TYROSINE PHOSPHORYLATION; FACTOR-ALPHA; INTEGRINS; CANCER; LINE AB Anchorage and growth factor independence are cardinal features of the transformed phenotype. Although it is logical that the two pathways must be coregulated in normal tissues to maintain homeostasis, this has not been demonstrated directly. We showed previously that down-modulation of beta 1-integrin signaling reverted the malignant behavior of a human breast tumor cell line (T4-2) derived from phenotypically normal cells (HMT-3522) and led to growth arrest in a three-dimensional (3D) basement membrane assay in which the cells formed tissue-like acini (14), Here, we show that there is a bidirectional cross-modulation of beta 1-integrin and epidermal growth factor receptor (EGFR) signaling via the mitogen-activated protein kinase (MAPK) pathway. The reciprocal modulation does not occur in monolayer (2D) cultures, Antibody-mediated inhibition of either of these receptors in the tumor cells, or inhibition of MAPK kinase, induced a concomitant downregulation of both receptors, followed by growth-arrest and restoration of normal breast tissue morphogenesis, Cross-modulation and tissue morphogenesis were associated with attenuation of EGF-induced transient MAPK activation. To specifically test EGFR and beta 1-integrin interdependency, EGFR was overexpressed in nonmalignant cells, leading to disruption of morphogenesis and a compensatory up-regulation of beta 1-integrin expression, again only in 3D, Our results indicate that when breast cells are spatially organized as a result of contact with basement membrane, the signaling pathways become coupled and bidirectional. They further explain,why breast cells fail to differentiate in monolayer cultures in which these events are mostly uncoupled. Moreover, in a subset of tumor cells in,which these pathways are misregulated but functional, the cells could be "normalized" by manipulating either pathway. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, Berkeley, CA 94720 USA. Univ Copenhagen, Panum Inst, Inst Med ANat, Struct Cell Biol Unit, DK-2200 Copenhagen N, Denmark. Jack Bell Res Ctr, Vancouver, BC V6H 3Z6, Canada. Danish Canc Soc, Div Canc Biol, Dept Tumor Endocrinol, DK-2100 Copenhagen O, Denmark. RP Bissell, MJ (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, Berkeley, CA 94720 USA. RI Wang, Fei/A-7968-2013 FU NCI NIH HHS [CA-64786, R01 CA064786, R37 CA064786] NR 41 TC 428 Z9 439 U1 0 U2 16 PU NATL ACAD SCIENCES PI WASHINGTON PA 2101 CONSTITUTION AVE NW, WASHINGTON, DC 20418 USA SN 0027-8424 J9 P NATL ACAD SCI USA JI Proc. Natl. Acad. Sci. U. S. A. PD DEC 8 PY 1998 VL 95 IS 25 BP 14821 EP 14826 DI 10.1073/pnas.95.25.14821 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 146NJ UT WOS:000077436700043 PM 9843973 ER PT J AU Allen, CD Breshears, DD AF Allen, CD Breshears, DD TI Drought-induced shift of a forest-woodland ecotone: Rapid landscape response to climate variation SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article ID VEGETATION; ECOSYSTEMS; RECORD; TIME; LAGS AB In coming decades, global climate changes are expected to produce large shifts in vegetation distributions at unprecedented rates. These shifts are expected to be most rapid and extreme at ecotones, the boundaries between ecosystems, particularly those in semiarid landscapes. However, current models do not adequately provide for such rapid effects-particularly those caused by mortality-largely because of the lack of data from field studies. Here we report the most rapid landscape-scale shift of a woody ecotone ever documented: in northern New Mexico in the 1950s, the ecotone between semiarid ponderosa pine forest and pinon-juniper woodland shifted extensively (2 km or more) and rapidly (<5 years) through mortality of ponderosa pines in response to a severe drought. This shift has persisted for 40 years. Forest patches within the shift zone became much more fragmented, and soil erosion greatly accelerated. The rapidity and the complex dynamics of the persistent shift point to the need to represent more accurately these dynamics, especially the mortality factor, in assessments of the effects of climate change. C1 US Geol Survey, Jemenz Mt Field Stn, Midcontinent Ecol Sci Ctr, Los Alamos, NM 87544 USA. Los Alamos Natl Lab, Environm Sci Grp, Los Alamos, NM 87545 USA. RP Allen, CD (reprint author), US Geol Survey, Jemenz Mt Field Stn, Midcontinent Ecol Sci Ctr, HCR 1,Box 1,15, Los Alamos, NM 87544 USA. EM craig_allen@usgs.gov; daveb@lanl.gov RI Breshears, David/B-9318-2009 OI Breshears, David/0000-0001-6601-0058 NR 48 TC 481 Z9 503 U1 15 U2 150 PU NATL ACAD SCIENCES PI WASHINGTON PA 2101 CONSTITUTION AVE NW, WASHINGTON, DC 20418 USA SN 0027-8424 J9 P NATL ACAD SCI USA JI Proc. Natl. Acad. Sci. U. S. A. PD DEC 8 PY 1998 VL 95 IS 25 BP 14839 EP 14842 DI 10.1073/pnas.95.25.14839 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 146NJ UT WOS:000077436700046 PM 9843976 ER PT J AU Kim, HS Lin, JY Jiang, HX Chow, WW Botchkarev, A Morkoc, H AF Kim, HS Lin, JY Jiang, HX Chow, WW Botchkarev, A Morkoc, H TI Piezoelectric effects on the optical properties of GaN/AlxGa1-xN multiple quantum wells SO APPLIED PHYSICS LETTERS LA English DT Article ID MOLECULAR-BEAM EPITAXY; GAN; PHOTOLUMINESCENCE; TRANSITIONS AB Piezoelectric effects on the optical properties of GaN/AlGaN multiple quantum wells (MQWs) have been investigated by picosecond time-resolved photoluminescence (PL) measurements. For MQWs with well thicknesses 30 and 40 Angstrom, the excitonic transition peak positions at 10 K in continuous wave (cw) spectra are redshifted with respect to the GaN epilayer by 13 and 45 meV, respectively. The time-resolved PL spectra of the 30 and 40 Angstrom well MQWs reveal that the excitonic transition is in fact blueshifted at early delay times due to quantum confinement of carriers. The spectral peak position shifts toward lower energies as the delay time increases and becomes redshifted at longer delay times. We have demonstrated that the results described above are due to the presence of the piezoelectric field in the GaN wells of GaN/AlGaN MQWs subject to elastic strain together with screening of the photoexcited carriers. By comparing experimental and calculation results, we conclude that the piezoelectric field strength in GaN/Al0.15Ga0.85N MQWs has a lower limit value of about 560 kV/cm. The electron and hole wave function distributions have also been obtained. The implication of our findings on the practical applications of GaN based optoelectronic devices is also discussed. (C) 1998 American Institute of Physics. [S0003-6951(98)04349-6]. C1 Kansas State Univ, Dept Phys, Manhattan, KS 66506 USA. Sandia Natl Labs, Albuquerque, NM 87518 USA. Virginia Commonwealth Univ, Dept Elect Engn & Phys, Richmond, VA 23284 USA. RP Kim, HS (reprint author), Kansas State Univ, Dept Phys, Manhattan, KS 66506 USA. RI Lin, Jingyu/A-7276-2011; Jiang, Hongxing/F-3635-2011 OI Lin, Jingyu/0000-0003-1705-2635; Jiang, Hongxing/0000-0001-9892-4292 NR 11 TC 103 Z9 104 U1 0 U2 10 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD DEC 7 PY 1998 VL 73 IS 23 BP 3426 EP 3428 DI 10.1063/1.122786 PG 3 WC Physics, Applied SC Physics GA 146MJ UT WOS:000077432600036 ER PT J AU Heuer, WB Lee, HS Kim, OK AF Heuer, WB Lee, HS Kim, OK TI Influence of hemicyanine dye structures on spectral properties of their supramolecular complexes with amylose SO CHEMICAL COMMUNICATIONS LA English DT Article ID INCLUSION COMPLEX AB Hemicyanine chromophores bearing long-chain alkyl substitutents on the donor and/or acceptor ends have been prepared, and absorption and emission spectra of their supramolecular complexes with amylose have been studied in order to relate them to their supramolecular structures. C1 USN, Res Lab, Div Chem, Washington, DC 20375 USA. USN Acad, Dept Chem, Annapolis, MD 21402 USA. Brookhaven Natl Lab, Div Mat Sci, Upton, NY 11973 USA. RP Kim, OK (reprint author), USN, Res Lab, Div Chem, Code 6120, Washington, DC 20375 USA. NR 13 TC 10 Z9 10 U1 0 U2 0 PU ROYAL SOC CHEMISTRY PI CAMBRIDGE PA THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON ROAD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND SN 1359-7345 J9 CHEM COMMUN JI Chem. Commun. PD DEC 7 PY 1998 IS 23 BP 2649 EP 2650 DI 10.1039/a808359b PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA 146LN UT WOS:000077430700049 ER PT J AU Grossman, Y Nir, Y Shadmi, Y AF Grossman, Y Nir, Y Shadmi, Y TI Large mixing and large hierarchy between neutrinos with Abelian flavor symmetries SO JOURNAL OF HIGH ENERGY PHYSICS LA English DT Article DE beyond Standard Model; supersymmetric Standard Model; neutrino physics ID BIG-BANG NUCLEOSYNTHESIS; DYNAMICAL SUPERSYMMETRY BREAKING; STERILE NEUTRINO; ATMOSPHERIC NEUTRINOS; DARK-MATTER; EARLY UNIVERSE; MASS-SPECTRUM; OSCILLATIONS; SOLAR; MODELS AB The experimental data on atmospheric and solar neutrinos suggest that there is near-maximal mixing between nu(mu) and nu(tau) but that their masses are hierarchically separated. In models of Abelian horizontal symmetries, mixing of O(1) generically implies that the corresponding masses are of the same order of magnitude. We describe two new mechanisms by which a large hierarchy between strongly mixed neutrinos can be achieved in this framework. First, a discrete Abelian symmetry can give the desired result in three ways: mass enhancement, mixing enhancement and mass suppression. Second, holomorphic zeros can give mass suppression. C1 Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. Weizmann Inst Sci, Dept Particle Phys, IL-76100 Rehovot, Israel. RP Grossman, Y (reprint author), Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. EM yuval@slac.stanford.edu; ftnir@clever.weizmann.ac.il; yshadami@wicc.weizmann.ac.il NR 47 TC 42 Z9 42 U1 0 U2 0 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1029-8479 J9 J HIGH ENERGY PHYS JI J. High Energy Phys. PD DEC 7 PY 1998 IS 10 AR 007 PG 16 WC Physics, Particles & Fields SC Physics GA 200CQ UT WOS:000080522400007 ER PT J AU Lee, TSH Oller, JA Oset, E Ramos, A AF Lee, TSH Oller, JA Oset, E Ramos, A TI Non-perturbative chiral approach to K(-)p ->gamma Y reactions SO NUCLEAR PHYSICS A LA English DT Article ID CLOUDY BAG MODEL; QUARK-MODEL; STATE INTERACTIONS; SCALAR MESONS; DYNAMICS; LAMBDA(1405); CHANNELS; CAPTURE; MASS AB A recently developed non-perturbative chiral approach to describe the S = -1 meson-baryon reactions has been extended to investigate the near threshold K(-)p --> gamma Lambda, gamma Sigma(0) reactions. With the parameters governed by chiral SU(3) symmetry, we show that the predicted branching ratios Gamma(K-p-->gamma Lambda)/Gamma(K-p-->all) and Gamma(K-p-->gamma Sigma 0)/Gamma(K-p-->all) are close to the experimental values. The coupling with the eta channels, which was shown to be important in the S = -1 meson-baryon reactions, is also found to be significant here. Our results are consistent with the interpretation of the Lambda(1405) as a quasi-bound meson-baryon state as found in other similar chiral approaches. (C) 1998 Elsevier Science B.V. C1 Univ Valencia, Dept Fis Teor, CSIC, E-46100 Burjassot, Valencia, Spain. Univ Valencia, IFIC, Ctr Mixto, CSIC, E-46100 Burjassot, Valencia, Spain. Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. Univ Barcelona, Dept Estructura & Constituents Mat, E-08028 Barcelona, Spain. RP Lee, TSH (reprint author), Univ Valencia, Dept Fis Teor, CSIC, E-46100 Burjassot, Valencia, Spain. RI Ramos, Angels/L-3043-2014 OI Ramos, Angels/0000-0002-0882-1570 NR 30 TC 18 Z9 18 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9474 J9 NUCL PHYS A JI Nucl. Phys. A PD DEC 7 PY 1998 VL 643 IS 4 BP 402 EP 414 DI 10.1016/S0375-9474(98)00581-8 PG 13 WC Physics, Nuclear SC Physics GA 149EJ UT WOS:000077591900004 ER PT J AU Chetyrkin, KG Kniehl, BA Steinhauser, M Bardeen, WA AF Chetyrkin, KG Kniehl, BA Steinhauser, M Bardeen, WA TI Effective QCD interactions of CP-odd Higgs bosons at three loops SO NUCLEAR PHYSICS B LA English DT Article ID MINIMAL SUPERSYMMETRIC MODEL; OPERATOR PRODUCT EXPANSION; DEEP-INELASTIC SCATTERING; PERTURBATIVE QCD; RADIATIVE-CORRECTIONS; PROTON COLLIDERS; QUANTUM CHROMODYNAMICS; COEFFICIENT FUNCTIONS; SUBTRACTION SCHEME; MS-SCHEME AB In the virtual presence of a heavy quark t, the interactions of a CP-odd scalar boson A, with mass M-A much less than 2M(t), with gluons and light quarks can be described by an effective Lagrangian. We analytically derive the coefficient functions of the respective physical operators to three loops in quantum chromodynamics (QCD), adopting the modified minimal-subtraction (MS) scheme of dimensional regularization. Special attention is paid to the proper treatment of the ys matrix and the Levi-Civita epsilon tensor in D dimensions. In the case of the effective ggA coupling, we fmd agreement with an all-order prediction based on a low-energy theorem in connection with the Adler-Bardeen non-renormalization theorem. This effective Lagrangian allows us to analytically evaluate the next-to-leading QCD correction to the A --> gg partial decay width by considering massless diagrams. For M-A = 100 GeV, the resulting correction factor reads 1 + (221/12)alpha(s)((5)) (M-A)/pi + 165.9 (alpha(s)((5)) (M-A)/pi)(2) approximate to 1 + 0.68 + 0.23. We compare this result with predictions based on various scale-optimization methods, (C) 1998 Published by Elsevier Science B.V. C1 Univ Karlsruhe, Inst Theoret Teilchenphys, D-76128 Karlsruhe, Germany. NYU, Dept Phys, New York, NY 10003 USA. Max Planck Inst Phys, Werner Heisenberg Inst, D-80805 Munich, Germany. Fermi Natl Accelerator Lab, Dept Theoret Phys, Batavia, IL 60510 USA. Russian Acad Sci, Inst Nucl Res, Moscow 117312, Russia. RP Chetyrkin, KG (reprint author), Univ Karlsruhe, Inst Theoret Teilchenphys, Kaiserstr 12, D-76128 Karlsruhe, Germany. NR 70 TC 42 Z9 42 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0550-3213 J9 NUCL PHYS B JI Nucl. Phys. B PD DEC 7 PY 1998 VL 535 IS 1-2 BP 3 EP 18 DI 10.1016/S0550-3213(98)00594-X PG 16 WC Physics, Particles & Fields SC Physics GA 149GG UT WOS:000077596300001 ER PT J AU Bhat, CM Bhat, PC Paterno, M Prosper, HB AF Bhat, CM Bhat, PC Paterno, M Prosper, HB TI Study of the solar neutrino survival probability SO PHYSICAL REVIEW LETTERS LA English DT Article ID MODEL UNCERTAINTIES; OSCILLATIONS AB We present a study af recent solar neutrino data using a Bayesian method. Assuming that only upsilon(e) are observed in the Super-Kamidkande experiment our results show a marked suppression of the survival probability at about 1 MeV, in good agreement with chi(2)-based analyses. When the detection of upsilon(mu) by Super-Kamiokande is taken into account, assuming upsilon(e) to upsilon(mu) oscillations, we find the largest suppression in survival probability at about 8.5 MeV. [S0031-9007(98)07835-1]. C1 Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Rochester, Dept Phys & Astron, Rochester, NY 14627 USA. Florida State Univ, Dept Phys, Tallahassee, FL 32306 USA. RP Bhat, CM (reprint author), Fermi Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. NR 30 TC 9 Z9 9 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD DEC 7 PY 1998 VL 81 IS 23 BP 5056 EP 5059 DI 10.1103/PhysRevLett.81.5056 PG 4 WC Physics, Multidisciplinary SC Physics GA 145GH UT WOS:000077362300005 ER PT J AU Avignone, FT Abriola, D Brodzinski, RL Collar, JI Creswick, RJ DiGregorio, DE Farach, HA Gattone, AO Guerard, CK Hasenbalg, F Huck, H Miley, HS Morales, A Morales, J Nussinov, S de Solorzano, AO Reeves, JH Villar, JA Zioutas, K AF Avignone, FT Abriola, D Brodzinski, RL Collar, JI Creswick, RJ DiGregorio, DE Farach, HA Gattone, AO Guerard, CK Hasenbalg, F Huck, H Miley, HS Morales, A Morales, J Nussinov, S de Solorzano, AO Reeves, JH Villar, JA Zioutas, K TI Experimental search for solar axions via coherent Primakoff conversion in a germanium spectrometer SO PHYSICAL REVIEW LETTERS LA English DT Article ID BRAGG SCATTERING; PARTICLES; DETECTOR AB Results are reported of an experimental search for the unique, rapidly varying temporal pattern of solar axions coherently converting into photons via the Primakoff effect in a single crystal germanium detector when axions are incident at a Bragg angle with a crystalline plane. The analysis of 1.94 kg yr of data from the I kg DEMOS detector in Sierra Grande, Argentina, yields a new laboratory bound by an axion-photon coupling of g(a gamma gamma) < 2.7 x 10(-9) GeV-1, independent of axion mass up to similar to 1 keV. [S0031-9007(98)07812-0]. C1 Univ S Carolina, Dept Phys & Astron, Columbia, SC 29208 USA. CNEA, TANDAR Lab, Dept Phys, Buenos Aires, DF, Argentina. Pacific NW Lab, Richland, WA 99352 USA. CERN, CH-1211 Geneva 23, Switzerland. Univ Zaragoza, Lab Fis Nucl & Altas Energias, Zaragoza, Spain. Tel Aviv Univ, Dept Phys, IL-69978 Tel Aviv, Israel. Univ Thessaloniki, Dept Phys, GR-54006 Thessaloniki, Greece. RP Univ S Carolina, Dept Phys & Astron, Columbia, SC 29208 USA. RI Villar, Jose Angel/K-6630-2014 OI Villar, Jose Angel/0000-0003-0228-7589 NR 24 TC 66 Z9 66 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 EI 1079-7114 J9 PHYS REV LETT JI Phys. Rev. Lett. PD DEC 7 PY 1998 VL 81 IS 23 BP 5068 EP 5071 DI 10.1103/PhysRevLett.81.5068 PG 4 WC Physics, Multidisciplinary SC Physics GA 145GH UT WOS:000077362300008 ER PT J AU Bai, JZ Bian, JG Blum, I Chai, ZW Chen, GP Chen, HF Chen, J Chen, JC Chen, Y Chen, YB Chen, YQ Cheng, BS Cui, XZ Ding, HL Ding, LY Dong, LY Du, ZZ Dunwoodie, W Feng, S Gao, CS Gao, ML Gao, SQ Gratton, P Gu, JH Gu, SD Gu, WX Gu, YF Guo, YN Han, SW Han, Y Harris, FA He, J He, JT He, M Hitlin, DG Hu, GY Hu, HM Hu, JL Hu, QH Hu, T Hu, XQ Huang, JD Huang, YZ Izen, JM Jiang, CH Jin, Y Ke, ZJ Kelsey, MH Kim, BK Kong, D Lai, YF Lang, PF Lankford, A Li, CG Li, D Li, HB Li, J Li, PQ Li, RB Li, W Li, WD Li, WG Li, XH Li, XN Liu, HM Liu, J Liu, JH Liu, RG Liu, Y Lou, XC Lowery, B Lu, F Lu, JG Lu, JY Lu, LC Luo, CH Ma, AM Ma, EC Ma, JM Malchow, R Mao, HS Mao, ZP Meng, XC Nie, J Olsen, SL Oyang, J Paluselli, D Pan, LJ Panetta, J Porter, F Qi, ND Qi, XR Qian, CD Qiu, JF Qu, YH Que, YK Rong, G Schernau, M Shao, YY Shen, BW Shen, DL Shen, H Shen, XY Sheng, HY Shi, HZ Song, XF Standifird, J Sun, F Sun, HS Tang, SQ Toki, W Tong, GL Wang, F Wang, LS Wang, LZ Wang, M Wang, M Wang, P Wang, PL Wang, SM Wang, TJ Wang, YY Weaver, M Wei, CL Wu, YG Xi, DM Xia, XM Xie, PP Xie, Y Xie, YH Xiong, WJ Xu, CC Xu, GF Xue, ST Yan, J Yan, WG Yang, CM Yang, CY Yang, J Yang, W Yang, XF Ye, MH Ye, SW Ye, YX Yi, K Yu, CS Yu, CX Yu, YH Yu, ZQ Yu, ZT Yuan, CZ Yuan, Y Zhang, BY Zhang, CC Zhang, DH Zhang, DH Zhang, HL Zhang, J Zhang, JL Zhang, JW Zhang, LS Zhang, QJ Zhang, SQ Zhang, XY Zhang, Y Zhang, YY Zhao, DX Zhao, HW Zhao, JW Zhao, M Zhao, WR Zhao, ZG Zheng, JP Zheng, LS Zheng, ZP Zhou, GP Zhou, HS Zhou, L Zhu, QM Zhu, YC Zhu, YS Zhuang, BA AF Bai, JZ Bian, JG Blum, I Chai, ZW Chen, GP Chen, HF Chen, J Chen, JC Chen, Y Chen, YB Chen, YQ Cheng, BS Cui, XZ Ding, HL Ding, LY Dong, LY Du, ZZ Dunwoodie, W Feng, S Gao, CS Gao, ML Gao, SQ Gratton, P Gu, JH Gu, SD Gu, WX Gu, YF Guo, YN Han, SW Han, Y Harris, FA He, J He, JT He, M Hitlin, DG Hu, GY Hu, HM Hu, JL Hu, QH Hu, T Hu, XQ Huang, JD Huang, YZ Izen, JM Jiang, CH Jin, Y Ke, ZJ Kelsey, MH Kim, BK Kong, D Lai, YF Lang, PF Lankford, A Li, CG Li, D Li, HB Li, J Li, PQ Li, RB Li, W Li, WD Li, WG Li, XH Li, XN Liu, HM Liu, J Liu, JH Liu, RG Liu, Y Lou, XC Lowery, B Lu, F Lu, JG Lu, JY Lu, LC Luo, CH Ma, AM Ma, EC Ma, JM Malchow, R Mao, HS Mao, ZP Meng, XC Nie, J Olsen, SL Oyang, J Paluselli, D Pan, LJ Panetta, J Porter, F Qi, ND Qi, XR Qian, CD Qiu, JF Qu, YH Que, YK Rong, G Schernau, M Shao, YY Shen, BW Shen, DL Shen, H Shen, XY Sheng, HY Shi, HZ Song, XF Standifird, J Sun, F Sun, HS Tang, SQ Toki, W Tong, GL Wang, F Wang, LS Wang, LZ Wang, M Wang, M Wang, P Wang, PL Wang, SM Wang, TJ Wang, YY Weaver, M Wei, CL Wu, YG Xi, DM Xia, XM Xie, PP Xie, Y Xie, YH Xiong, WJ Xu, CC Xu, GF Xue, ST Yan, J Yan, WG Yang, CM Yang, CY Yang, J Yang, W Yang, XF Ye, MH Ye, SW Ye, YX Yi, K Yu, CS Yu, CX Yu, YH Yu, ZQ Yu, ZT Yuan, CZ Yuan, Y Zhang, BY Zhang, CC Zhang, DH Zhang, DH Zhang, HL Zhang, J Zhang, JL Zhang, JW Zhang, LS Zhang, QJ Zhang, SQ Zhang, XY Zhang, Y Zhang, YY Zhao, DX Zhao, HW Zhao, JW Zhao, M Zhao, WR Zhao, ZG Zheng, JP Zheng, LS Zheng, ZP Zhou, GP Zhou, HS Zhou, L Zhu, QM Zhu, YC Zhu, YS Zhuang, BA TI psi(2S) hadronic decays to vector-tensor final states SO PHYSICAL REVIEW LETTERS LA English DT Article ID RHO-PI PUZZLE; POSSIBLE EXPLANATION; J/PSI; PHYSICS; PSI' AB The decays of the psi(2S) into vector plus tensor meson final states have been studied for the first time using the BES detector. We determine upper limits on branching fractions for psi(2S) decays into omega f(2), pa(2), + c.c., and phi f(2)'(1525) that are, in each case, significantly smaller than the corresponding branching fractions for the J/psi meson, scaled according to the expectations of perturbative QCD. [S0031-9007(98)07836-3]. C1 Inst High Energy Phys, Beijing 100039, Peoples R China. CALTECH, Pasadena, CA 91125 USA. Colorado State Univ, Ft Collins, CO 80523 USA. Hangzhou Univ, Hangzhou 310028, Peoples R China. Shandong Univ, Jinan 250100, Peoples R China. Shanghai Jiao Tong Univ, Shanghai 200030, Peoples R China. Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. Univ Hawaii, Honolulu, HI 96822 USA. Univ Calif Irvine, Irvine, CA 92717 USA. Univ Sci & Technol China, Hefei 230026, Peoples R China. Univ Texas, Richardson, TX 75083 USA. RP Bai, JZ (reprint author), Inst High Energy Phys, Beijing 100039, Peoples R China. RI Chen, Yu/E-3788-2012; Lu, Lanchun/E-3551-2011; OI Li, Xiaonan/0000-0003-2857-0219 NR 16 TC 26 Z9 28 U1 0 U2 5 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD DEC 7 PY 1998 VL 81 IS 23 BP 5080 EP 5084 DI 10.1103/PhysRevLett.81.5080 PG 5 WC Physics, Multidisciplinary SC Physics GA 145GH UT WOS:000077362300011 ER PT J AU Mardor, I Durrant, S Aclander, J Alster, J Barton, D Bunce, G Carroll, A Christensen, N Courant, H Gushue, S Heppelmann, S Kosonovsky, E Mardor, Y Marshak, M Makdisi, Y Minor, ED Navon, I Nicholson, H Piasetzky, E Roser, T Russell, J Suttor, CS Tanaka, M White, C Wu, JY AF Mardor, I Durrant, S Aclander, J Alster, J Barton, D Bunce, G Carroll, A Christensen, N Courant, H Gushue, S Heppelmann, S Kosonovsky, E Mardor, Y Marshak, M Makdisi, Y Minor, ED Navon, I Nicholson, H Piasetzky, E Roser, T Russell, J Suttor, CS Tanaka, M White, C Wu, JY TI Nuclear transparency in large momentum transfer quasielastic scattering SO PHYSICAL REVIEW LETTERS LA English DT Article ID COLOR TRANSPARENCY; ELASTIC-SCATTERING; DEPENDENCE; ANGLE AB We measured simultaneously pp elastic and quasielastic (p,2p) scattering in hydrogen, deuterium, and carbon for momentum transfers of 4.8 to 6.2 (GeV/c)(2) at incoming momenta of 5.9 and 7.5 GeV/c and center-of-mass scattering angles in the range theta(c.m.) = 83.7 degrees-90 degrees. The nuclear transparency is defined as the ratio of the quasielastic cross section to the free pp cross section. At incoming momentum of 5.9 GeV/c, the transparency of carbon decreases by a factor of 2 from theta(c.m.) = 85 degrees to theta(c.m.) similar or equal to 89 degrees. At the largest angle the transparency of carbon increases from 5.9 to 7.5 GeV/c by more than 50%. The transparency in deuterium does not depend on incoming momentum nor an theta(c.m.). [S0031-9007(98)07818-1]. C1 Tel Aviv Univ, Sackler Fac Exact Sci, Sch Phys & Astron, IL-69978 Ramat Aviv, Israel. Brookhaven Natl Lab, Upton, NY 11973 USA. Univ Minnesota, Dept Phys, Minneapolis, MN 55455 USA. Penn State Univ, Dept Phys, University Pk, PA 16802 USA. Mt Holyoke Coll, S Hadley, MA 01075 USA. Univ Massachusetts, Dept Phys, N Dartmouth, MA 02747 USA. RP Mardor, I (reprint author), Soreq NRC, IL-81800 Yavne, Israel. RI Marshak, Marvin/B-8645-2008 NR 23 TC 40 Z9 40 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD DEC 7 PY 1998 VL 81 IS 23 BP 5085 EP 5088 DI 10.1103/PhysRevLett.81.5085 PG 4 WC Physics, Multidisciplinary SC Physics GA 145GH UT WOS:000077362300012 ER PT J AU Yan, Y Pennycook, SJ Tsai, AP AF Yan, Y Pennycook, SJ Tsai, AP TI Direct imaging of local chemical disorder and columnar vacancies in ideal decagonal Al-Ni-Co quasicrystals SO PHYSICAL REVIEW LETTERS LA English DT Article ID QUASI-CRYSTALS; ORDERED STRUCTURES; AL65CU20CO15 AB Atomic-resolution Z-contrast images provide direct images of chemical disorder and columnar vacancies in an ideal Al-Ni-Co decagonal quasicrystal. Chemical disorder occurs in the central ring of the 2 nm clusters and involves both Al and Ni(Co) atoms. Columnar vacancies are observed in the form of closely spaced, half-occupied atomic columns in specific rings within the clusters. This structure, derived from real space images, differs significantly from previous atomic models. [S0031-9007(98)07839-9]. C1 Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Natl Res Inst Met, Tsukuba, Ibaraki 305, Japan. RP Yan, Y (reprint author), Oak Ridge Natl Lab, Div Solid State, POB 2008, Oak Ridge, TN 37831 USA. NR 25 TC 81 Z9 82 U1 2 U2 7 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD DEC 7 PY 1998 VL 81 IS 23 BP 5145 EP 5148 DI 10.1103/PhysRevLett.81.5145 PG 4 WC Physics, Multidisciplinary SC Physics GA 145GH UT WOS:000077362300027 ER PT J AU Finnis, MW Paxton, AT Methfessel, M van Schilfgaarde, M AF Finnis, MW Paxton, AT Methfessel, M van Schilfgaarde, M TI Crystal structures of zirconia from first principles and self-consistent tight binding SO PHYSICAL REVIEW LETTERS LA English DT Article ID SOLIDS; ZRO2 AB The origin of the relative stability of the cubic, tetragonal, and monoclinic phases of zirconia (ZrO2) is investigated. To obtain accurate energies we adopt a new all-electron bandstructure approach within the local density approximation, based on muffin tin orbitals. We also develop a self-consistent tight-binding model with which to study the energies for different structures. The tight-binding model enables us to analyze ab initio and experimental phase stabilities in terms of ionic versus covalent effects, including polarization of the anions, and promises to be useful for rapid simulation of more complex systems. [S0031-9007(98)07811-9]. C1 Queens Univ Belfast, Dept Pure & Appl Phys, Atom Simulat Grp, Belfast BT7 1NN, Antrim, North Ireland. Inst Semicond Phys, D-15230 Frankfurt, Germany. Sandia Natl Labs, Livermore, CA 94551 USA. RP Finnis, MW (reprint author), Queens Univ Belfast, Dept Pure & Appl Phys, Atom Simulat Grp, Belfast BT7 1NN, Antrim, North Ireland. OI Paxton, Anthony/0000-0003-4182-8210 NR 18 TC 69 Z9 70 U1 1 U2 21 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD DEC 7 PY 1998 VL 81 IS 23 BP 5149 EP 5152 DI 10.1103/PhysRevLett.81.5149 PG 4 WC Physics, Multidisciplinary SC Physics GA 145GH UT WOS:000077362300028 ER PT J AU Frank, G Qiu, JZ Somsouk, M Weng, YH Somsouk, L Nolan, JP Shen, BH AF Frank, G Qiu, JZ Somsouk, M Weng, YH Somsouk, L Nolan, JP Shen, BH TI Partial functional deficiency of E160D flap endonuclease-1 mutant in vitro and in vivo is due to defective cleavage of DNA substrates SO JOURNAL OF BIOLOGICAL CHEMISTRY LA English DT Article ID NUCLEOTIDE EXCISION-REPAIR; SACCHAROMYCES-CEREVISIAE; POLYMERASE-I; 5'-NUCLEASE DOMAIN; REPLICATION FORK; ESCHERICHIA-COLI; MU-TRANSPOSASE; 3' EXONUCLEASE; ACTIVE-SITE; RNASE-H AB To assess the roles of the active site residues Glu(160) and Asp(181) of human FEN-1 nuclease in binding and catalysis of the flap DNA substrate and in vivo biological processes of DNA damage and repair, five different amino acids were replaced at each site through site-directed mutagenesis of the FEN-1 gene. The mutants were then expressed in Escherichia coli and purified using a His-tag. Even though the mutants bind to the flap DNA to different degrees, most of the mutants lost flap nuclease activity with the exception of an E160D mutant. This mutant retained wild type-like binding ability, specificity, and partial catalytic activity. Detailed steady state and pre-steady state kinetic analysis revealed that the functional deficiency of this mutant was due to retardation of the endonucleolytic cleavage. When the mutant enzyme E160D was expressed in yeast, it partially complements the biological functions of the homologous yeast gene, RAD27, and reverses the hyper-temperature lethality and hypersensitivity to methyl methanesulfonate, in a manner corresponding to the in vitro activity. C1 City Hope Natl Med Ctr, Dept Cell & Tumor Biol, Duarte, CA 91010 USA. City Hope Natl Med Ctr, Beckman Res Inst, Duarte, CA 91010 USA. Los Alamos Natl Lab, Div Life Sci, Los Alamos, NM 87545 USA. RP Shen, BH (reprint author), City Hope Natl Med Ctr, Dept Cell & Tumor Biol, 1500 E Duarte Rd, Duarte, CA 91010 USA. EM bshen@coh.org FU NCI NIH HHS [CA73764-02] NR 52 TC 39 Z9 39 U1 1 U2 3 PU AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3996 USA SN 0021-9258 EI 1083-351X J9 J BIOL CHEM JI J. Biol. Chem. PD DEC 4 PY 1998 VL 273 IS 49 BP 33064 EP 33072 DI 10.1074/jbc.273.49.33064 PG 9 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 144RP UT WOS:000077329100100 PM 9830061 ER PT J AU Hutcheon, ID Krot, AN Keil, K Phinney, DL Scott, ERD AF Hutcheon, ID Krot, AN Keil, K Phinney, DL Scott, ERD TI Mn-53-Cr-53 dating of fayalite formation in the CV3 chondrite mokoia: Evidence for asteroidal alteration SO SCIENCE LA English DT Article ID EARLY SOLAR-SYSTEM; HIGH-TEMPERATURE CONDENSATION; PARENT BODY; AQUEOUS ALTERATION; ALLENDE METEORITE; CARBONACEOUS CHONDRITES; NEBULA; OLIVINE; AL-26; KABA AB Fayalite grains in chondrules in the oxidized, aqueously altered CV3 chondrite Mokoia have large excesses of radiogenic chromium-53. These excesses indicate the in situ decay of short-lived manganese-53 (half-Life = 3.7 million years) and define an initial Mn-53/Mn-55 ratio of 2.32 (+/-0.18) x 10(-6). This ratio is comparable to values for carbonates in CI and CM chondrites and for several classes of differentiated meteorites. Mokoia fayalites formed 7 to 16 million years after Allende calcium-aluminum-rich inclusions, during hydrothermal activity on a geologically active asteroid after chondritic components had ceased forming in the solar nebula. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Univ Hawaii Manoa, Sch Ocean & Earth Sci & Technol, Hawaii Inst Geophys & Planetol, Honolulu, HI 96822 USA. RP Hutcheon, ID (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 58 TC 56 Z9 57 U1 0 U2 3 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 USA SN 0036-8075 J9 SCIENCE JI Science PD DEC 4 PY 1998 VL 282 IS 5395 BP 1865 EP 1867 DI 10.1126/science.282.5395.1865 PG 3 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 144WG UT WOS:000077338100041 PM 9836631 ER PT J AU Lu, HP Xun, LY Xie, XS AF Lu, HP Xun, LY Xie, XS TI Single-molecule enzymatic dynamics SO SCIENCE LA English DT Article ID BREVIBACTERIUM-STEROLICUM; CHOLESTEROL OXIDASE; ELECTRON-TRANSFER; KINETICS; FLUCTUATIONS; SPECTROSCOPY; BEHAVIOR; ENERGY; TRANSITIONS; DIFFUSION AB Enzymatic turnovers of single cholesterol oxidase molecules were observed in real time by monitoring the emission from the enzyme's fluorescent active site, flavin adenine dinucleotide (FAD), Statistical analyses of single-molecule trajectories revealed a significant and slow fluctuation in the rate of cholesterol oxidation by FAD. The static disorder and dynamic disorder of reaction rates, which are essentially indistinguishable in ensemble-averaged experiments, were determined separately by the real-time single-molecule approach. A molecular memory phenomenon, in which an enzymatic turnover was not independent of its previous turnovers because of a slow fluctuation of protein conformation, was evidenced by spontaneous spectral fluctuation of FAD. C1 Pacific NW Natl Lab, William R Wiley Environm Mol Sci Lab, Richland, WA 99352 USA. Washington State Univ, Dept Microbiol, Pullman, WA 99164 USA. RP Xie, XS (reprint author), Pacific NW Natl Lab, William R Wiley Environm Mol Sci Lab, Richland, WA 99352 USA. EM xsxie@pnl.gov NR 44 TC 997 Z9 1025 U1 18 U2 181 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 USA SN 0036-8075 J9 SCIENCE JI Science PD DEC 4 PY 1998 VL 282 IS 5395 BP 1877 EP 1882 DI 10.1126/science.282.5395.1877 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 144WG UT WOS:000077338100045 PM 9836635 ER PT J AU Hirano, T Demura, M George, EP Umezawa, O AF Hirano, T Demura, M George, EP Umezawa, O TI Fabrication of large-grained binary stoichiometric Ni3Al SO SCRIPTA MATERIALIA LA English DT Article ID ROOM-TEMPERATURE DUCTILITY; BORON-DOPED NI3AL; UNIDIRECTIONAL SOLIDIFICATION; RECRYSTALLIZATION; IMPROVEMENT; TEXTURE; SHEETS C1 Natl Res Inst Met, Ibaraki, Osaka 3050047, Japan. Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Hirano, T (reprint author), Natl Res Inst Met, 1-2-1 Sengen, Ibaraki, Osaka 3050047, Japan. RI UMEZAWA, Osamu/C-9702-2012; George, Easo/L-5434-2014 OI UMEZAWA, Osamu/0000-0003-0380-1885; NR 18 TC 1 Z9 1 U1 0 U2 2 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1359-6462 J9 SCRIPTA MATER JI Scr. Mater. PD DEC 4 PY 1998 VL 40 IS 1 BP 63 EP 69 DI 10.1016/S1359-6462(98)00392-3 PG 7 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 151TF UT WOS:000077736200011 ER PT J AU Micic, OI Jones, KM Cahill, A Nozik, AJ AF Micic, OI Jones, KM Cahill, A Nozik, AJ TI Optical, electronic, and structural properties of uncoupled and close-packed arrays of InP quantum dots SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID VAPOR-PHASE EPITAXY; SELF-ORGANIZATION; NANOCRYSTALS; SIZE; MONOLAYERS; GROWTH; SUPERLATTICES; SPECTROSCOPY; TRANSITION; PARTICLES AB Solid films consisting of close-packed arrays of InP quantum dots have been prepared by slowly evaporating colloidal solutions of InP quantum dots. The diameters of the quantum dots were controlled to be between about 30 to 60 Angstrom; size-selective precipitation yielded a size distribution of about 10% about the mean diameter. The arrays show regions of hexagonal order, as well as disordered regions. Oxide layers can form irreversibly on the quantum dot surface and limit the effectiveness of the size-selective precipitation. Photoluminescence spectra obtained from close-packed films of InP quantum dots formed from quantum dots with a single mean diameter and from a mixture of two quantum dot sizes show that energy transfer occurs from the photoexcited smaller quantum dots to the larger quantum dots. The efficiency of this energy transfer process is high. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Nozik, AJ (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. RI Nozik, Arthur/A-1481-2012; Nozik, Arthur/P-2641-2016 NR 58 TC 178 Z9 179 U1 1 U2 29 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5647 J9 J PHYS CHEM B JI J. Phys. Chem. B PD DEC 3 PY 1998 VL 102 IS 49 BP 9791 EP 9796 DI 10.1021/jp981703u PG 6 WC Chemistry, Physical SC Chemistry GA 146ZV UT WOS:000077464500005 ER PT J AU Chen, SW Murray, RW Feldberg, SW AF Chen, SW Murray, RW Feldberg, SW TI Quantized capacitance charging of monolayer-protected Au clusters SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID GOLD; MOLECULES; COLLOIDS; SILVER; THIOL; ELECTROCHEMISTRY; NANOPARTICLES; ELECTRODES; PARTICLES; PLATINUM AB A theoretical model based on electrostatic interactions is developed to account for the formal potentials of current peaks observed in differential pulse voltammetry of solutions of 10 different nanometer-sized alkylthiolate and arylthiolate monolayer-protected gold clusters. The current peaks arise from successive, quantized (single-electron) capacitative charging of ensembles of individual cluster cores (i.e., electrochemical ensemble Coulomb staircase charging). Experimental peak potentials for a given cluster change roughly linearly with changes in its core charge state, as predicted by the theory, and the sub-attofarad capacitances (C-CLU) of individual clusters obtained from the slopes of such plots agree with those estimated from a simple concentric sphere capacitor model. The charging of clusters with very small cores becomes redox molecule-like, indicating as reported recently, the emergence of HOMO-LUMO energy gaps. Because the quantized charging currents of the clusters are diffusion controlled, their voltammetric behavior can be readily simulated, but requires attention to dispersities in C-CLU that occur in experimental samples of these materials. Simulations of microelectrode voltammetry incorporating Gaussian dispersions in cluster properties display features similar to those observed experimentally. The simulations show that quantized charging features are more difficult to detect when the nanoparticles are not monodisperse, but can be seen in polydisperse samples when the cores are small (small C-CLU) and not highly charged. C1 Univ N Carolina, Kenan Labs Chem, Chapel Hill, NC 27599 USA. Brookhaven Natl Lab, Dept Appl Sci, Upton, NY 11973 USA. RP Murray, RW (reprint author), Univ N Carolina, Kenan Labs Chem, Chapel Hill, NC 27599 USA. RI Chen, Shaowei/B-5171-2013 OI Chen, Shaowei/0000-0002-3668-8551 NR 36 TC 250 Z9 251 U1 4 U2 37 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5647 J9 J PHYS CHEM B JI J. Phys. Chem. B PD DEC 3 PY 1998 VL 102 IS 49 BP 9898 EP 9907 DI 10.1021/jp982822c PG 10 WC Chemistry, Physical SC Chemistry GA 146ZV UT WOS:000077464500019 ER PT J AU Gregg, BA Cormier, RA AF Gregg, BA Cormier, RA TI Liquid crystal perylene diimide films characterized by electrochemical, spectroelectrochemical, and conductivity versus potential measurements SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID INTERDIGITATED MICROARRAY ELECTRODES; CHEMICALLY MODIFIED ELECTRODES; MOLECULAR-METALS; POLYMER-FILMS; BIS(PHENETHYLIMIDE) FILMS; N-METHYLPYRROLE; NAFION MATRIX; THIN-FILMS; PHTHALOCYANINE; REDOX AB Electrochemical techniques are used to characterize thin polycrystalline films of a liquid crystal perylene diimide. Cyclic voltammograms show evidence for strong attractive interactions between the perylene diimide molecules and suggest that the film undergoes two structural rearrangements to accommodate reduction to the anionic and dianionic states. Spectroelectrochemical measurements support this interpretation. The redox conductivity of the film as a function of electrochemical potential was measured with the use of interdigitated array electrodes. The conductivity reaches the semiconducting level before the occurrence of the first noticeable reduction wave. The maximum conductivity, 4.4 x 10(-2) Slcm, occurs when the film is reduced by 1 equiv of electrons, in contrast to the expectation that this state should be a Mott insulator. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. Metropolitan State Coll, Dept Chem, Denver, CO 80204 USA. RP Gregg, BA (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. NR 43 TC 44 Z9 44 U1 3 U2 15 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5647 J9 J PHYS CHEM B JI J. Phys. Chem. B PD DEC 3 PY 1998 VL 102 IS 49 BP 9952 EP 9957 DI 10.1021/jp982842e PG 6 WC Chemistry, Physical SC Chemistry GA 146ZV UT WOS:000077464500027 ER PT J AU Bond, AM Feldberg, SW AF Bond, AM Feldberg, SW TI Analysis of simulated reversible cyclic voltammetric responses for a charged redox species in the absence of added electrolyte SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID SUPPORTING ELECTROLYTE AB We present an analysis of simulated cyclic voltammetric responses of a dissolved redox salt with no added supporting electrolyte. The redox system of interest is a reversible one electron transfer: A(zA) + e = BzA-1 Only the charged, oxidized species A(zA) and counterion X-zx are initially present in solution (analogous systems where the reduced species and counterion are initially present are not explicitly discussed); their relative concentrations are dictated by Z(A), Z(X), and the constraint of electroneutrality (systems where z(A) = 0 or 1 are not considered). Cyclic voltammetric responses are simulated assuming Nernst-Planck transport, and electroneutrality with perfect IR compensation (easily simulated but experimentally unattainable) and with partial IR compensation. Simulations assuming perfect compensation allow us to elucidate the change in the resistance, R-ref between the working and reference electrodes effected by changes in the depletion layer during the course of the cyclic voltammetric perturbation. Simulation of systems with (more realistic) partial compensation leads to an empirical linear equation which correlates E degrees with cathodic peak potential, E-pc: E-pc = E degrees + (RT/F)[b(z) - 1.347((F/RT)I-pc(1 - gamma)R-ref(0) )(0.929)], where I-pc is the cathodic peak current, R-ref(0) is the resistance of the bulk solution (prior to the CV perturbation) between the working and reference electrodes, and gamma is the fraction of that resistance compensated (by positive feedback) during the perturbation. The constant b(z) is a function of Z(A) (range -1000 to +1000) and z(x) (+/-1, +/-2) with weak dependence on D-X/D-A (range 0.5-2) when D-A = D-B (D-X, D-A, and D-B are the diffusion coefficients of species X, A, and B, respectively). The numerical parameters 1.347 and 0.929 remain constant for the ranges of charges and diffusion coefficients studied. C1 Monash Univ, Dept Chem, Clayton, Vic 3168, Australia. Brookhaven Natl Lab, Dept Appl Sci, Upton, NY 11973 USA. RP Feldberg, SW (reprint author), Monash Univ, Dept Chem, Clayton, Vic 3168, Australia. NR 13 TC 25 Z9 25 U1 1 U2 6 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5647 J9 J PHYS CHEM B JI J. Phys. Chem. B PD DEC 3 PY 1998 VL 102 IS 49 BP 9966 EP 9974 DI 10.1021/jp9828437 PG 9 WC Chemistry, Physical SC Chemistry GA 146ZV UT WOS:000077464500029 ER PT J AU Zhou, J Case, MA Wishart, JF McLendon, GL AF Zhou, J Case, MA Wishart, JF McLendon, GL TI Thermodynamic and structural effects of a single backbone hydrogen bond deletion in a metal-assembled helical bundle protein SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID DE-NOVO DESIGN; ELECTRON-TUNNELING PATHWAYS; BINDING-ENERGY; COILED COILS; PEPTIDES; SEQUENCES; COMPLEXES; CHEMISTRY; CORES; SITE AB Transition metal ion-assembled three-helix bundle proteins provide templates to investigate the thermodynamic and dynamic structural consequences of the deletion of a single backbone hydrogen bond from an alpha-helical architecture. This deletion does not perturb the steady-state secondary structure of the protein as measured by circular dichroism spectroscopy but does decrease the overall folding free energy by ca. 0.7 kcal/mol. We have used intraprotein electron transfer as a measure of the structure-sensitive dynamics of our system. The deletion of a single hydrogen bond in one of the helices of a three-helix bundle does not significantly change the measured electron-transfer rate. This is in agreement with "Greenpath" electron-transfer pathway calculations, which assume a constant and invariant structure for the architecture. Given the exponential dependence of electron-transfer rate on distance and that fluctuations in the intervening secondary structure will cause variations in electron donor-acceptor distances, the measured electron-transfer rate associated with hydrogen bond deletion allows us to calculate a differential dynamic structural fluctuation associated with hydrogen bond deletion of less than 0.6 Angstrom over the millisecond lime scale of the experiment. C1 Princeton Univ, Dept Chem, Princeton, NJ 08544 USA. Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. RP McLendon, GL (reprint author), Princeton Univ, Dept Chem, Princeton, NJ 08544 USA. RI Wishart, James/L-6303-2013 OI Wishart, James/0000-0002-0488-7636 NR 54 TC 18 Z9 18 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5647 J9 J PHYS CHEM B JI J. Phys. Chem. B PD DEC 3 PY 1998 VL 102 IS 49 BP 9975 EP 9980 DI 10.1021/jp982852f PG 6 WC Chemistry, Physical SC Chemistry GA 146ZV UT WOS:000077464500030 ER PT J AU Woychik, RP Klebig, ML Justice, MJ Magnuson, TR Avner, ED AF Woychik, RP Klebig, ML Justice, MJ Magnuson, TR Avner, ED TI Functional genomics in the post-genome era (vol 400, pg 3, 1998) SO MUTATION RESEARCH-FUNDAMENTAL AND MOLECULAR MECHANISMS OF MUTAGENESIS LA English DT Correction C1 Case Western Reserve Univ, Rainbow Babies & Childrens Hosp, Dept Pediat, Cleveland, OH 44106 USA. Case Western Reserve Univ, Dept Genet, Cleveland, OH 44106 USA. Oak Ridge Natl Lab, Div Life Sci, Oak Ridge, TN 37831 USA. RP Woychik, RP (reprint author), Case Western Reserve Univ, Rainbow Babies & Childrens Hosp, Dept Pediat, 11100 Euclid Ave, Cleveland, OH 44106 USA. NR 1 TC 0 Z9 0 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0027-5107 J9 MUTAT RES-FUND MOL M JI Mutat. Res.-Fundam. Mol. Mech. Mutagen. PD DEC 3 PY 1998 VL 422 IS 2 BP 367 EP 367 PG 1 WC Biotechnology & Applied Microbiology; Genetics & Heredity; Toxicology SC Biotechnology & Applied Microbiology; Genetics & Heredity; Toxicology GA 153DC UT WOS:000077817000020 ER PT J AU Dorey, N Khoze, VV Mattis, MP Vandoren, S AF Dorey, N Khoze, VV Mattis, MP Vandoren, S TI Yang-Mills instantons in the large-N limit and the AdS/CFT correspondence SO PHYSICS LETTERS B LA English DT Article ID SUPERSYMMETRIC GAUGE-THEORY; MULTIINSTANTON CALCULUS; BRANES AB We examine a certain 16-fermion correlator in N = 4 supersymmetric SU(N) gauge theory in 4 dimensions. Generalizing recent SU(2) results of Bianchi, Green, Kovacs and Rossi, we calculate the exact N-dependence of the effective 16-fermion vertex at the 1-instanton level, and find precise agreement in the large-N limit with the prediction of the type IIB superstring on AdS(5) x S-5. This suggests that the string theory prediction for the 1-instanton amplitude considered here is not corrected by higher-order terms in the alpha' expansion. (C) 1998 Published by Elsevier Science B.V. All rights reserved. C1 Univ Wales Swansea, Dept Phys, Swansea SA2 8PP, W Glam, Wales. Univ Washington, Dept Phys, Seattle, WA 98195 USA. Univ Durham, Ctr Particle Theory, Dept Phys, Durham DH1 3LE, England. Univ Calif Los Alamos Natl Lab, Div Theoret T8, Los Alamos, NM 87545 USA. RP Dorey, N (reprint author), Univ Wales Swansea, Dept Phys, Swansea SA2 8PP, W Glam, Wales. OI Khoze, Valentin V/0000-0003-3006-4147 NR 34 TC 37 Z9 37 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 J9 PHYS LETT B JI Phys. Lett. B PD DEC 3 PY 1998 VL 442 IS 1-4 BP 145 EP 151 DI 10.1016/S0370-2693(98)01233-7 PG 7 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 150LT UT WOS:000077666900022 ER PT J AU Weber, H Ernst, C Bleicher, M Bravina, L Stocker, H Greiner, W Spieles, C Bass, SA AF Weber, H Ernst, C Bleicher, M Bravina, L Stocker, H Greiner, W Spieles, C Bass, SA TI Excitation function of energy density and partonic degrees of freedom in relativistic heavy ion collisions SO PHYSICS LETTERS B LA English DT Article ID NUCLEUS-NUCLEUS COLLISIONS; QUARK-GLUON PLASMA; SUPERDENSE MATTER; HADRONIC MATTER; DYNAMICS; EQUATION; STATE; QCD; CASCADES AB We estimate the energy density epsilon pile-up at mid-rapidity in central Ph + Pb collisions from 2-200 GeV/nucleon. epsilon is decomposed into hadronic and partonic contributions. A detailed analysis of the collision dynamics in the framework of a microscopic transport model shows the importance of partonic degrees of freedom and rescattering of leading (di)quarks in the early phase of the reaction for E-lab greater than or equal to 30 GeV/nucleon. In Pb + Pb collisions at 160 GeV/nucleon the energy density reaches up to 4 GeV/fm(3), 95% of which are contained in partonic degrees of freedom. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Univ Frankfurt, Inst Theoret Phys, D-60054 Frankfurt, Germany. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Duke Univ, Dept Phys, Durham, NC 27708 USA. RP Weber, H (reprint author), Univ Frankfurt, Inst Theoret Phys, Robert Mayer Str 8-10, D-60054 Frankfurt, Germany. RI Bleicher, Marcus/A-2758-2010; Stoecker, Horst/D-6173-2013; OI Stoecker, Horst/0000-0002-3282-3664; Bass, Steffen/0000-0002-9451-0954 NR 29 TC 17 Z9 17 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 J9 PHYS LETT B JI Phys. Lett. B PD DEC 3 PY 1998 VL 442 IS 1-4 BP 443 EP 448 DI 10.1016/S0370-2693(98)01252-0 PG 6 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 150LT UT WOS:000077666900063 ER PT J AU Airapetian, A Akopov, N Akushevich, I Amarian, M Aschenauer, EC Avakian, H Avakian, R Avetissian, A Bains, B Baumgarten, C Beckmann, M Belostotski, S Belz, E Benisch, T Bernreuther, S Bianchi, N Blouw, J Bottcher, H Borissov, A Brack, J Brauksiepe, S Braun, B Brons, S Bruckner, W Brull, A Bulten, HJ Capitani, GP Carter, P Chumney, P Cisbani, E Court, GR Dalpiaz, PF De Leo, R De Sanctis, E De Schepper, D Devitsin, E Huberts, PKAD Di Nezza, P Duren, M Dvoredsky, A Elbakian, G Ely, J Fantoni, A Fechtchenko, A Ferstl, M Fick, D Fiedler, K Filippone, BW Fischer, H Fox, B Frabetti, S Franz, J Frullani, S Funk, MA Gagunashvili, ND Gao, H Garber, Y Garibaldi, F Gavrilov, G Geiger, P Gharibyan, V Giordjian, V Golendukhin, A Graw, G Grebeniouk, O Green, PW Greeniaus, LG Grosshauser, C Guidal, M Gute, A Haeberli, W Hansen, JO Hasch, D Heinsius, FH Henoch, M Hertenberger, R Holler, Y Holt, RJ Hoprich, W Ihssen, H Iodice, M Izotov, A Jackson, HE Jgoun, A Kaiser, R Kinney, E Kisselev, A Kitching, P Kobayashi, H Koch, N Konigsmann, K Kolstein, M Kolster, H Korotkov, V Korsch, W Kozlov, V Kramer, LH Krivokhijine, VG Kummell, F Kurisuno, M Kyle, G Lachnit, W Lorenzon, W Makins, NCR Manaenkov, SI Martens, K Martin, JW Marukyan, H Masoli, F Mateos, A McAndrew, M McIlhany, K McKeown, RD Meissner, F Menden, F Metz, A Meyners, N Mikloukho, O Miller, CA Miller, MA Milner, R Mitsyn, V Most, A Muccifora, V Nagaitsev, A Nappi, E Naryshkin, Y Nathan, AM Neunreither, F Nowak, WD O'Neill, TG Owen, BR Ouyang, J Papavassiliou, V Pate, SF Potashov, S Potterveld, DH Rakness, G Relai, A Redwine, R Reolon, AR Ristinen, R Rith, K Roloff, H Rossi, P Rudnitsky, S Ruh, M Ryckbosch, D Sakemi, Y Savin, I Scarlett, C Schmidt, F Schmitt, H Schnell, G Schuler, KP Schwind, A Seibert, J Shibata, TA Shibatani, K Shin, T Shutov, V Simani, C Simon, A Sinram, K Slavich, P Spengos, M Steffens, E Stenger, J Stewart, J Stosslein, U Sutter, M Tallini, H Taroian, S Terkulov, A Tipton, B Tytgat, M Urciuoli, GM Van de Vyver, R van den Brand, JFJ van der Steenhoven, G van Hunen, JJ Vetterli, MC Vincter, M Visser, J Volk, E Wander, W Williamson, SE Wise, T Woller, K Yoneyama, S Zohrabian, H AF Airapetian, A Akopov, N Akushevich, I Amarian, M Aschenauer, EC Avakian, H Avakian, R Avetissian, A Bains, B Baumgarten, C Beckmann, M Belostotski, S Belz, E Benisch, T Bernreuther, S Bianchi, N Blouw, J Bottcher, H Borissov, A Brack, J Brauksiepe, S Braun, B Brons, S Bruckner, W Brull, A Bulten, HJ Capitani, GP Carter, P Chumney, P Cisbani, E Court, GR Dalpiaz, PF De Leo, R De Sanctis, E De Schepper, D Devitsin, E Huberts, PKAD Di Nezza, P Duren, M Dvoredsky, A Elbakian, G Ely, J Fantoni, A Fechtchenko, A Ferstl, M Fick, D Fiedler, K Filippone, BW Fischer, H Fox, B Frabetti, S Franz, J Frullani, S Funk, MA Gagunashvili, ND Gao, H Garber, Y Garibaldi, F Gavrilov, G Geiger, P Gharibyan, V Giordjian, V Golendukhin, A Graw, G Grebeniouk, O Green, PW Greeniaus, LG Grosshauser, C Guidal, M Gute, A Haeberli, W Hansen, JO Hasch, D Heinsius, FH Henoch, M Hertenberger, R Holler, Y Holt, RJ Hoprich, W Ihssen, H Iodice, M Izotov, A Jackson, HE Jgoun, A Kaiser, R Kinney, E Kisselev, A Kitching, P Kobayashi, H Koch, N Konigsmann, K Kolstein, M Kolster, H Korotkov, V Korsch, W Kozlov, V Kramer, LH Krivokhijine, VG Kummell, F Kurisuno, M Kyle, G Lachnit, W Lorenzon, W Makins, NCR Manaenkov, SI Martens, K Martin, JW Marukyan, H Masoli, F Mateos, A McAndrew, M McIlhany, K McKeown, RD Meissner, F Menden, F Metz, A Meyners, N Mikloukho, O Miller, CA Miller, MA Milner, R Mitsyn, V Most, A Muccifora, V Nagaitsev, A Nappi, E Naryshkin, Y Nathan, AM Neunreither, F Nowak, WD O'Neill, TG Owen, BR Ouyang, J Papavassiliou, V Pate, SF Potashov, S Potterveld, DH Rakness, G Relai, A Redwine, R Reolon, AR Ristinen, R Rith, K Roloff, H Rossi, P Rudnitsky, S Ruh, M Ryckbosch, D Sakemi, Y Savin, I Scarlett, C Schmidt, F Schmitt, H Schnell, G Schuler, KP Schwind, A Seibert, J Shibata, TA Shibatani, K Shin, T Shutov, V Simani, C Simon, A Sinram, K Slavich, P Spengos, M Steffens, E Stenger, J Stewart, J Stosslein, U Sutter, M Tallini, H Taroian, S Terkulov, A Tipton, B Tytgat, M Urciuoli, GM Van de Vyver, R van den Brand, JFJ van der Steenhoven, G van Hunen, JJ Vetterli, MC Vincter, M Visser, J Volk, E Wander, W Williamson, SE Wise, T Woller, K Yoneyama, S Zohrabian, H CA HERMES Collaboration TI Measurement of the proton spin structure function g(1)(p) with a pure hydrogen target SO PHYSICS LETTERS B LA English DT Article ID DEUTERON STRUCTURE FUNCTIONS; DEEP-INELASTIC-SCATTERING; POLARIZATION; F-2(P) AB A measurement of the proton spin structure function g(l)(p)(x, Q(2)) in deep-inelastic scattering is presented. The data were taken with the 27.6 GeV longitudinally polarised positron beam at HERA incident on a longitudinally polarised pure hydrogen gas target internal to the storage ring. The kinematic range is 0.021 < x < 0.85 and 0.8 GeV2 < Q(2) < 20 GeV2. The integral integral(0.021)(0.85) g(l)(p)(x) dx evaluated at Q(0)(2) of 2.5 GeV2 is 0.122 +/- 0.003(stat.) +/- 0.010(syst.). (C) Elsevier Science B.V. All rights reserved. C1 Yerevan Phys Inst, Yerevan 375036, Armenia. Univ Alberta, Dept Phys, Edmonton, AB T6G 2N2, Canada. Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. Ist Nazl Fis Nucl, Sez Bari, I-70124 Bari, Italy. CALTECH, WK Kellogg Radiat Lab, Pasadena, CA 91125 USA. Univ Colorado, Nucl Phys Lab, Boulder, CO 80309 USA. DESY, D-22603 Hamburg, Germany. DESY, D-15738 Zeuthen, Germany. Joint Inst Nucl Res, Dubna 141980, Russia. Univ Erlangen Nurnberg, Inst Phys, D-91058 Erlangen, Germany. Univ Ferrara, Dipartimento Fis, I-44100 Ferrara, Italy. Ist Nazl Fis Nucl, Lab Nazl Frascati, I-00044 Frascati, Italy. Florida Int Univ, Dept Phys, Miami, FL 33199 USA. Univ Freiburg, Fak Phys, D-79104 Freiburg, Germany. State Univ Ghent, Dept Subatom & Radiat Phys, B-9000 Ghent, Belgium. Max Planck Inst Kernphys, D-69029 Heidelberg, Germany. Univ Illinois, Dept Phys, Urbana, IL 61801 USA. Univ Kentucky, Dept Phys & Astron, Lexington, KY 40506 USA. Univ Liverpool, Dept Phys, Liverpool L69 7ZE, Merseyside, England. Univ Wisconsin, Dept Phys, Madison, WI 53706 USA. Univ Marburg, Inst Phys, D-35037 Marburg, Germany. MIT, Nucl Sci Lab, Cambridge, MA 02139 USA. Univ Michigan, Randall Lab Phys, Ann Arbor, MI 48109 USA. PN Lebedev Phys Inst, Moscow 117924, Russia. Univ Munich, Sekt Phys, D-85748 Garching, Germany. New Mexico State Univ, Dept Phys, Las Cruces, NM 88003 USA. NIKHEF, NL-1009 DB Amsterdam, Netherlands. Petersburg Nucl Phys Inst, St Petersburg 188350, Russia. Ist Nazl Fis Nucl, Sez Sanita, I-00161 Rome, Italy. Simon Fraser Univ, Dept Phys, Burnaby, BC V5A 1S6, Canada. TRIUMF, Vancouver, BC V6T 2A3, Canada. Tokyo Inst Technol, Dept Phys, Tokyo 152, Japan. Free Univ Amsterdam, Dept Phys & Astron, NL-1081 HV Amsterdam, Netherlands. RP Airapetian, A (reprint author), Yerevan Phys Inst, Yerevan 375036, Armenia. RI Gao, Haiyan/G-2589-2011; Gavrilov, Gennady/C-6260-2013; Holt, Roy/E-5803-2011; Kozlov, Valentin/M-8000-2015; Terkulov, Adel/M-8581-2015; Cisbani, Evaristo/C-9249-2011; OI Cisbani, Evaristo/0000-0002-6774-8473; Heinsius, Fritz-Herbert/0000-0002-9545-5117 NR 28 TC 224 Z9 224 U1 2 U2 8 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 J9 PHYS LETT B JI Phys. Lett. B PD DEC 3 PY 1998 VL 442 IS 1-4 BP 484 EP 492 DI 10.1016/S0370-2693(98)01341-0 PG 9 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 150LT UT WOS:000077666900069 ER PT J AU Kriesel, JW Konig, S Freitas, MA Marshall, AG Leary, JA Tilley, TD AF Kriesel, JW Konig, S Freitas, MA Marshall, AG Leary, JA Tilley, TD TI Synthesis of highly charged organometallic dendrimers and their characterization by electrospray mass spectrometry and single-crystal X-ray diffraction SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID ION-CYCLOTRON RESONANCE; DENDRITIC MACROMOLECULES; STARBURST DENDRIMERS; SILANE DENDRIMERS; CASCADE MOLECULES; METAL-COMPLEXES; BUILDING-BLOCKS; POLYSILANE; CATALYSIS; CHEMISTRY AB Four new carbosilane dendrimers terminated with 12, 24, 36, and 72 benzyl groups have been synthesized and characterized by matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry. These dendrimers were capped with Cp*Ru+ to yield polycations containing charges of 12+, 24+, 36+, and 72+. The charged dendrimers comprise the largest such structures thus far characterized by electrospray ionization (ESI) mass spectrometry. Additionally, for the first time full resolution of individual isotopic distributions has been achieved using ESI FT-ICR techniques, thereby providing unambiguous confirmation of the charges and nuclearities of the dendrimers. The first-generation, ruthenium-containing dendrimer (G1-Ru-12) was also characterized by single-crystal X-ray diffraction. This polycation has a molecular volume significantly larger than any dendrimer thus far characterized by this technique. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA. Natl High Magnet Field Lab, Ctr Interdisciplinary Magnet Resonance, Tallahassee, FL 32310 USA. Florida State Univ, Dept Chem, Tallahassee, FL 32306 USA. RP Tilley, TD (reprint author), Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. RI Freitas, Michael/C-8953-2009 OI Freitas, Michael/0000-0002-3103-8410 NR 58 TC 54 Z9 55 U1 0 U2 7 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0002-7863 J9 J AM CHEM SOC JI J. Am. Chem. Soc. PD DEC 2 PY 1998 VL 120 IS 47 BP 12207 EP 12215 DI 10.1021/ja981610q PG 9 WC Chemistry, Multidisciplinary SC Chemistry GA 145JG UT WOS:000077367000006 ER PT J AU Barich, DH Nicholas, JB Xu, T Haw, JF AF Barich, DH Nicholas, JB Xu, T Haw, JF TI Theoretical and experimental study of the C-13 chemical shift tensors of acetone complexed with Bronsted and Lewis acids SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID NUCLEAR-MAGNETIC-RESONANCE; SOLID-STATE NMR; IN-SITU NMR; INCLUDING ATOMIC ORBITALS; SHIELDING TENSORS; PERTURBATION-THEORY; LOCALIZED QUANTITIES; CAVERN DESIGN; BASIS-SETS; CHEMISTRY AB We calculated the chemical shift tensors for acetone and 12 complexes of acetone with Bronsted and Lewis acids. Each complex was optimized at the MP2/6-311+G* or B3LYP/DZVP2 level of theory. Chemical shift tensors were calculated with the gauge including atomic orbital (GIAO) approach at the RHF and MP2 levels of theory. We discovered a strong correlation between the MP2 and RHF C-13 isotropic shifts of the carbonyl carbon in the complexes studied. Linear regression indicates that the MP2 isotropic shifts can be predicted by delta(MP2) = [1.12 (+/-0.04)]delta(RHF) - 42.1 (+/-10.5) ppm (R-2 = 0.9974). We were thus able to study two systems that are currently intractable at the GIAO-MP2 level. One is the complex of acetone with a large model of a zeolite, (H3SiO)(3)SiOHAl(OSiH3)(3). The RHF shift of the carbonyl carbon of acetone on the zeolite model (238.4 ppm) is in poor agreement with the experimental (223 ppm) value. However, the MP2 result predicted by the linear correlation (224.0 ppm) is in much closer agreement. We were also able to study acetone adsorbed on aluminum chloride powder models. We find that acetone . AlCl3 isa poor adsorption model, as demonstrated by a large discrepancy between experimental and calculated MP2 shifts. However, the MP2 shift from the regression equation (244.7 ppm) for acetone complexed to the larger Al2Cl6 cluster is in excellent agreement with the experimental result (245 ppm). We also report experimental measurements of the principal components of the carbonyl C-13 Shift tensor for a variety of solid acids, including frozen oleum and frozen SbF5. C1 Texas A&M Univ, Dept Chem, Ctr Catalysis, College Stn, TX 77842 USA. Pacific NW Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Haw, JF (reprint author), Texas A&M Univ, Dept Chem, Ctr Catalysis, POB 300012, College Stn, TX 77842 USA. NR 50 TC 48 Z9 50 U1 1 U2 12 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0002-7863 J9 J AM CHEM SOC JI J. Am. Chem. Soc. PD DEC 2 PY 1998 VL 120 IS 47 BP 12342 EP 12350 DI 10.1021/ja982226w PG 9 WC Chemistry, Multidisciplinary SC Chemistry GA 145JG UT WOS:000077367000021 ER PT J AU Evans, JSO Hanson, JC Sleight, AW AF Evans, JSO Hanson, JC Sleight, AW TI Room-temperature superstructure of ZrV2O7 SO ACTA CRYSTALLOGRAPHICA SECTION B-STRUCTURAL SCIENCE LA English DT Article ID NEGATIVE THERMAL-EXPANSION; BOND; NMR AB The structure of ZrV2O7, zirconium pyrovanadate, has been refined from single-crystal synchrotron X-ray data. As with other phases in the AM(2)O(7) family, ZrV2O7 shows a set of strong reflections, which can be explained on the basis of a cubic unit cell with a = 8.765 Angstrom, and a family of much weaker reflections due to a 3 x 3 x 3 superstructure. The superstructure has been refined to R-F = 0.036 (a = 26.296 Angstrom, Pa (3) over bar, 6972 reflections) and contains highly regular ZrO6 and VO4 polyhedra. Of the six unique V2O7 groups, two are constrained by symmetry to contain linear V-O-V linkages, while the remaining four are free to bend away from 180 degrees. The structural distortions from the ideal high-symmetry structure to the observed room-temperature structure are described. C1 Oregon State Univ, Dept Chem, Corvallis, OR 97331 USA. Oregon State Univ, Ctr Adv Mat, Corvallis, OR 97331 USA. Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. RP Evans, JSO (reprint author), Oregon State Univ, Dept Chem, Gilbert Hall 153, Corvallis, OR 97331 USA. RI Hanson, jonathan/E-3517-2010; Evans, John/E-6345-2012 OI Evans, John/0000-0001-6305-6341 NR 32 TC 47 Z9 49 U1 3 U2 11 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0108-7681 J9 ACTA CRYSTALLOGR B JI Acta Crystallogr. Sect. B-Struct. Sci. PD DEC 1 PY 1998 VL 54 BP 705 EP 713 DI 10.1107/S0108768198000962 PN 6 PG 9 WC Chemistry, Multidisciplinary; Crystallography SC Chemistry; Crystallography GA 152UF UT WOS:000077794600001 ER PT J AU Teslic, S Egami, T AF Teslic, S Egami, T TI Atomic structure of PbZrO3 determined by pulsed neutron diffraction SO ACTA CRYSTALLOGRAPHICA SECTION B-STRUCTURAL SCIENCE LA English DT Article ID LEAD-ZIRCONATE-TITANATE; ANTIFERROELECTRIC PBZRO3; POWDER DIFFRACTION; PHASE-TRANSITIONS; FERROELECTRICITY; REFINEMENT; DISORDER AB The atomic structure of lead zirconate, PbZrO3 (PZ), was studied using Rietveld refinement and atomic pair distribution function analysis of pulsed neutron powder diffraction data for the antiferroelectric, intermediate and paraelectric phases. The symmetry of PZ at T = 20 K in the antiferroelectric phase was determined to be Pbam. The structure was characterized by distortions of the ZrO6 octahedra which are smaller than in previous studies. Locally correlated displacements of Pb in the c direction develop with increasing temperature. The average magnitude was 0.06 Angstrom at room temperature, 0.14 Angstrom at T = 473 K and 0.20 Angstrom in the intermediate phase at T = 508 K. The intermediate phase was characterized by in-plane antiferroelectric Pb displacements which produce 1/2{110} superlattice diffraction peaks. Above 473 K the local structure of PZ remains largely unchanged, in spite of the transitions in the long-range order from the antiferroelectric to the intermediate and to the paraelectric phases. C1 Univ Penn, Dept Mat Sci & Engn, Philadelphia, PA 19104 USA. Univ Penn, Res Struct Matter Lab, Philadelphia, PA 19104 USA. RP Teslic, S (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. EM egami@seas.upenn.edu NR 35 TC 83 Z9 85 U1 1 U2 12 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0108-7681 J9 ACTA CRYSTALLOGR B JI Acta Crystallogr. Sect. B-Struct. Sci. PD DEC 1 PY 1998 VL 54 BP 750 EP 765 DI 10.1107/S0108768198003802 PN 6 PG 16 WC Chemistry, Multidisciplinary; Crystallography SC Chemistry; Crystallography GA 152UF UT WOS:000077794600006 ER PT J AU Zurek, WH AF Zurek, WH TI Decoherence, chaos, quantum-classical correspondence and the arrow of time SO ACTA PHYSICA POLONICA B LA English DT Article; Proceedings Paper CT XXXVIII Cracow School of Theoretical Physics CY JUN 01-10, 1998 CL ZAKOPANE, POLAND ID BROWNIAN-MOTION; SOLAR-SYSTEM; WAVE PACKET; STATES; EVOLUTION; MECHANICS AB The environment - external or internal degrees of freedom coupled to the object of interest - can, in effect, monitor some of its observables. As a result, the eigenstates of these observables decohere and behave like classical states. Continuous destruction of superpositions leads to the effective environment-induced superselection (einselection), which is beginning to be recognized as a key step in the transition from quantum to classical. We investigate it here in the context of quantum chaos. I show that the evolution of a chaotic macroscopic system is not just difficult to predict (requiring accuracy exponentially increasing with time) but quickly ceases to be deterministic in principle as a result of the Heisenberg; uncertainty (which limits the available resolution). This happens after a time tt, which is only logarithmic in the Planck constant. For example, various components of the solar system are chaotic, with the Lyapunov timescales ranging from a bit more then a month (Hyperion) to millions of years (planetary system as a whole). On the timescale th the initial minimum uncertainty wavepackets corresponding to celestial bodies would be smeared over distances of the order of radii of their orbits into "Schrodinger cat-like" states, and the very concept of a "trajectory" would cease to apply. In reality, such paradoxical states are eliminated by decoherence which helps restore quantum-classical correspondence. The price for the recovery of classicality is the loss of predictability. In the classical limit (associated not with the smallness of (h) over bar, but with decoherence) the rate of increase of entropy is independent of the strength of the coupling to the environment, and equal to the sum of the positive Lyapunov exponents. I end by noting that the cost of information transfer between systems - of the action measured in units of (g) over bar's per bit - decreases with the increasing size. This suggests why information may seem to be so irrelevant for classical dynamics, and yet is obviously so crucial at the quantum level. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Zurek, WH (reprint author), Univ Calif Los Alamos Natl Lab, T-6,Mail Stop B288, Los Alamos, NM 87545 USA. NR 52 TC 7 Z9 7 U1 0 U2 0 PU ACTA PHYSICA POLONICA B, JAGELLONIAN UNIV, INST PHYSICS PI KRAKOW PA REYMONTA 4, 30-059 KRAKOW, POLAND SN 0587-4254 J9 ACTA PHYS POL B JI Acta Phys. Pol. B PD DEC PY 1998 VL 29 IS 12 BP 3689 EP 3709 PG 21 WC Physics, Multidisciplinary SC Physics GA 163QA UT WOS:000078415600006 ER PT J AU Stull, JT Lin, PJ Krueger, JK Trewhella, J Zhi, G AF Stull, JT Lin, PJ Krueger, JK Trewhella, J Zhi, G TI Myosin light chain kinase: functional domains and structural motifs SO ACTA PHYSIOLOGICA SCANDINAVICA LA English DT Article; Proceedings Paper CT 3rd Acta Physiologica Scandinavica International Symposium on Signalling Mechanisms in Vascular Smooth Muscle CY MAY 21-25, 1998 CL MARGRETETORP, SWEDEN SP Acta Physiol Scandinav DE actin; calcium; calmodulin; kinase; myosin light chain kinase; smooth muscle ID SMOOTH-MUSCLE MYOSIN; OXIDE SYNTHASE ACTIVITIES; DEPENDENT PROTEIN-KINASE; INTRASTERIC REGULATION; TROPONIN-C; CALMODULIN-BINDING; CATALYTIC SUBUNIT; PEPTIDE COMPLEX; ACTIVATION; PHOSPHORYLATION AB Conventional myosin light chain kinase found in differentiated smooth and non-muscle cells is a dedicated Ca2+/calmodulin-dependent protein kinase which phosphorylates the regulatory light chain of myosin II. This phosphorylation increases the actin-activated myosin ATPase activity and is thought to play major roles in a number of biological processes, including smooth muscle contraction. The catalytic domain contains residues on its surface that bind a regulatory segment resulting in autoinhibition through an intrasteric mechanism. When Ca2+/calmodulin binds, there is a marked displacement of the regulatory segment from the catalytic cleft allowing phosphorylation of myosin regulatory light chain. Kinase activity depends upon Ca2+/calmodulin binding not only to the canonical calmodulin-binding sequence but also to additional interactions between Ca2+/calmodulin and the catalytic core. Previous biochemical evidence shows myosin light chain kinase binds tightly to actomyosin containing filaments. The! kinase has low-affinity myosin and actin binding sites in Ig-like motifs at the N- and C-terminus, respectively. Recent results how the N-terminus of myosin light chain kinase is responsible for filament binding in vivo. However, the apparent binding affinity is greater for smooth muscle myofilaments, purified thin filaments, or actin-containing filaments in permeable cells than for purified smooth muscle F-actin or actomyosin filaments from skeletal muscle. These results suggest a protein on actin thin filaments that may facilitate kinase binding. Myosin light chain kinase does not dissociate from filaments in the presence of Ca2+/calmodulin raising the interesting question as to how the kinase phosphorylates myosin in thick filaments if it is bound to actin-containing thin filaments. C1 Univ Texas, SW Med Ctr, Dept Physiol, Dallas, TX 75235 USA. Univ Calif Los Alamos Natl Lab, Chem Sci & Technol Div, Los Alamos, NM USA. RP Stull, JT (reprint author), Univ Texas, SW Med Ctr, Dept Physiol, 5323 Harry Hines Blvd, Dallas, TX 75235 USA. RI Krueger, Joanna/A-3110-2011; OI Trewhella, Jill/0000-0002-8555-6766 NR 69 TC 54 Z9 57 U1 1 U2 5 PU BLACKWELL SCIENCE LTD PI OXFORD PA P O BOX 88, OSNEY MEAD, OXFORD OX2 0NE, OXON, ENGLAND SN 0001-6772 J9 ACTA PHYSIOL SCAND JI Acta Physiol. Scand. PD DEC PY 1998 VL 164 IS 4 BP 471 EP 482 PG 12 WC Physiology SC Physiology GA 153RX UT WOS:000077847400015 PM 9887970 ER PT J AU Bhardwaj, MK Kapania, RK Reichenbach, E Guruswamy, GP AF Bhardwaj, MK Kapania, RK Reichenbach, E Guruswamy, GP TI Computational fluid dynamics computational structural dynamics interaction methodology for aircraft wings SO AIAA JOURNAL LA English DT Article ID EQUATIONS AB With advanced subsonic transports and military aircraft operating in the transonic regime, it is becoming important to determine the effects of the coupling between aerodynamic loads and elastic forces. Because aeroelastic effects can significantly impact the design of these aircraft, there is a strong need in the aerospace industry to predict these interactions computationally. Such an analysis in the transonic regime requires high-fidelity computational fluid dynamics (CFD) analysis tools, due to the nonlinear behavior of the aerodynamics, and high-fidelity computational structural dynamics (CSD) analysis tools. Also, there is a need to be able to use a wide variety of CFD and CSD methods to predict aeroelastic effects. Because source codes are not always available, it is necessary to couple the CFD and CSD codes without alteration of the source codes. In this study, an aeroelastic coupling procedure is developed to determine the static aeroelastic response of aircraft wings using any CFD and CSD code with little code integration. The procedure is demonstrated on an F/A-18 stabilator using NASTD tan in-house McDonnell Douglas CFD code) and NASTRAN. In addition, the Aeroelastic Research Wing is used for demonstration with ENSAERO (NASA Ames Research Center CFD code) coupled with a finite element wing-box code. The results obtained from the present study are compared with those available from an experimental study conducted at NASA Langley Research Center and a study conducted at NASA Ames Research Center using ENSAERO and modal superposition. The results compare well with experimental data. C1 Virginia Polytech Inst & State Univ, Dept Aerosp & Ocean Engn, Blacksburg, VA 24061 USA. Boeing Co, Aeromech Dept, St Louis, MO 63166 USA. NASA, Ames Res Ctr, Appl Computat Aerodynam Branch, Moffett Field, CA 94035 USA. RP Bhardwaj, MK (reprint author), Sandia Natl Labs, Struct Dynam Dept, Limited Term Staff, POB 5800,MS-0439, Albuquerque, NM 87185 USA. NR 43 TC 20 Z9 20 U1 1 U2 3 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 USA SN 0001-1452 J9 AIAA J JI AIAA J. PD DEC PY 1998 VL 36 IS 12 BP 2179 EP 2186 DI 10.2514/2.342 PG 8 WC Engineering, Aerospace SC Engineering GA 148KK UT WOS:000077503900004 ER PT J AU Devroye, L Mucke, EP Zhu, BH AF Devroye, L Mucke, EP Zhu, BH TI A note on point location in delaunay triangulations of random points SO ALGORITHMICA LA English DT Article DE Voronoi diagram; Delaunay triangulation; point location; probabilistic analysis of algorithms; computational geometry ID COMPUTING DIRICHLET TESSELLATIONS; VORONOI DIAGRAMS; CONSTRUCTION; SUBDIVISIONS; ALGORITHMS; TREE AB This short note considers the problem of point location in a Delaunay triangulation of n random points, using no additional preprocessing or storage other than a standard data structure representing the triangulation. A simple and easy-to-implement (but, of course, worst-case suboptimal) heuristic is shown to take expected time O(n(1/3)). C1 McGill Univ, Sch Comp Sci, Montreal, PQ H3A 2A7, Canada. ANSYS Inc, Houston, PA 15342 USA. City Univ Hong Kong, Dept Comp Sci, Kowloon, Hong Kong. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Devroye, L (reprint author), McGill Univ, Sch Comp Sci, Montreal, PQ H3A 2A7, Canada. RI Zhu, Binhai/A-2911-2008 NR 24 TC 29 Z9 34 U1 1 U2 4 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0178-4617 J9 ALGORITHMICA JI Algorithmica PD DEC PY 1998 VL 22 IS 4 BP 477 EP 482 DI 10.1007/PL00009234 PG 6 WC Computer Science, Software Engineering; Mathematics, Applied SC Computer Science; Mathematics GA 139NE UT WOS:000077034800006 ER PT J AU Yeung, E AF Yeung, E TI HPCE '99 SO AMERICAN LABORATORY LA English DT Article C1 Iowa State Univ Sci & Technol, Dept Chem, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, US DOE, Ames Lab, Ames, IA 50011 USA. RP Yeung, E (reprint author), Iowa State Univ Sci & Technol, Dept Chem, Ames, IA 50011 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU INT SCIENTIFIC COMMUN INC PI SHELTON PA PO BOX 870, 30 CONTROLS DRIVE, SHELTON, CT 06484-0870 USA SN 0044-7749 J9 AM LAB JI Am. Lab. PD DEC PY 1998 VL 30 IS 24 BP 43 EP 44 PG 2 WC Chemistry, Analytical; Instruments & Instrumentation SC Chemistry; Instruments & Instrumentation GA 150DC UT WOS:000077646900009 ER PT J AU Grate, JW Egorov, OB AF Grate, JW Egorov, OB TI Automating analytical separations in radiochemistry SO ANALYTICAL CHEMISTRY LA English DT Article ID PLASMA-MASS-SPECTROMETRY; SOLID-PHASE EXTRACTION; SEQUENTIAL-INJECTION-ANALYSIS; FLOW-INJECTION; NUCLEAR WASTE; RADIONUCLIDE DETECTION; ION-CHROMATOGRAPHY; ACTINIDES; PRECONCENTRATION; CHEMISTRY C1 Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Grate, JW (reprint author), Pacific NW Natl Lab, Environm Mol Sci Lab, POB 999, Richland, WA 99352 USA. NR 34 TC 34 Z9 34 U1 2 U2 14 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0003-2700 J9 ANAL CHEM JI Anal. Chem. PD DEC 1 PY 1998 VL 70 IS 23 BP 779A EP 788A PG 10 WC Chemistry, Analytical SC Chemistry GA 143VW UT WOS:000077278700010 ER PT J AU Amad, MH Houk, RS AF Amad, MH Houk, RS TI High-resolution mass spectrometry with a multiple pass quadrupole mass analyzer SO ANALYTICAL CHEMISTRY LA English DT Article ID ION-MOLECULE REACTION; STABILITY REGION; FILTER; TRAP; CHARGE AB The peak shape narrows and the resolution improves if the ions are simply reflected back and forth through a conventional quadrupole mass analyzer, CO+ and N-2(+) at m/z = 28 are separated to 50% valley with half of the original signal remaining. These two ions can be resolved to baseline (m/Delta m) = 5000 with 1% of the original signal remaining. C1 Iowa State Univ Sci & Technol, Dept Chem, Ames Lab, US DOE, Ames, IA 50011 USA. RP Houk, RS (reprint author), Iowa State Univ Sci & Technol, Dept Chem, Ames Lab, US DOE, Ames, IA 50011 USA. NR 29 TC 8 Z9 8 U1 1 U2 6 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0003-2700 J9 ANAL CHEM JI Anal. Chem. PD DEC 1 PY 1998 VL 70 IS 23 BP 4885 EP 4889 DI 10.1021/ac980505w PG 5 WC Chemistry, Analytical SC Chemistry GA 143VW UT WOS:000077278700015 PM 21644671 ER PT J AU Yang, LY Lee, CS Hofstadler, SA Smith, RD AF Yang, LY Lee, CS Hofstadler, SA Smith, RD TI Characterization of microdialysis acidification for capillary isoelectric focusing microelectrospray ionization mass spectrometry SO ANALYTICAL CHEMISTRY LA English DT Article ID ELECTROSPRAY-IONIZATION; ZONE ELECTROPHORESIS; CYTOCHROME-C; PROTEINS; INTERFACE; OPTIMIZATION; SENSITIVITY; TRANSFERRIN; SAMPLES AB A microdialysis junction, based on a microdialysis membrane connecting a separation capillary and a short, sharply tapered microelectrospray emitter capillary, is demonstrated for on-line combination of capillary isoelectric focusing (CIEF) with electrospray ionization mass spectrometry (ESI-MS). The microdialysis junction provides the necessary electrical connection across the dialysis membrane for defining the electric fields needed for the CIEF separation and the electrospray process. Additionally, postseparation acidification of focused protein zones eluted from the CIEF capillary is achieved using the microdialysis junction while separation efficiency and resolution is maintained. A microelectrospray emitter produces a stable electrospray of protein analytes without the need for a makeup liquid flow and eliminates any subsequent sample dilution and reduction in MS sensitivity. The microdialysis junction is advantageous over the coaxial liquid sheath interface as evidenced by the simplicity in operation procedures, the enhancement in detection sensitivity, and the linear correlation between protein migration time and isoelectric point in CIEF-ESI-MS. C1 Iowa State Univ, US DOE, Dept Chem, Ames, IA 50011 USA. Iowa State Univ, US DOE, Ames Lab, Ames, IA 50011 USA. RP Lee, CS (reprint author), Univ Maryland, Dept Chem & Biochem, College Pk, MD 20742 USA. EM chenglee@iastate.edu; rd_smith@pnl.gov RI Smith, Richard/J-3664-2012 OI Smith, Richard/0000-0002-2381-2349 NR 32 TC 51 Z9 52 U1 0 U2 5 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0003-2700 J9 ANAL CHEM JI Anal. Chem. PD DEC 1 PY 1998 VL 70 IS 23 BP 4945 EP 4950 DI 10.1021/ac980223w PG 6 WC Chemistry, Analytical SC Chemistry GA 143VW UT WOS:000077278700024 PM 9852780 ER PT J AU Gillen, KT Keenan, MR Wise, J AF Gillen, KT Keenan, MR Wise, J TI New method for predicting lifetime of seals from compression stress relaxation experiments SO ANGEWANDTE MAKROMOLEKULARE CHEMIE LA English DT Article; Proceedings Paper CT 20th International Conference on Advances in the Stabilization and Degradation of Polymers CY JUN 10-12, 1998 CL LUZERN, SWITZERLAND ID DIFFUSION-LIMITED OXIDATION; TIME DEVELOPMENT; EXTRAPOLATION; ARRHENIUS; PROFILES; MODEL AB Interpretation of compression stress-relaxation (CSR) experiments for elastomers in air is complicated by (1) the presence of both physical and chemical relaxation and (2) anomalous diffusion-limited oxidation (DLO) effects. For a butyl material, we first use shear relaxation data to indicate that physical relaxation effects are negligible during typical high temperature CSR experiments. We then show that experiments on standard CSR samples (similar to 15 mm diameter when compressed) lead to complex non-Arrhenius behavior. By combining reaction kinetics based on the historic basic autoxidation scheme with a diffusion equation appropriate to disk-shaped samples, we derive a theoretical DLO model appropriate to CSR experiments. Using oxygen consumption and permeation rate measurements, the theory shows that important DLO effects are responsible for the observed non-Arrhenius behavior. To minimize DLO effects, we introduce a new CSR methodology based on the use of numerous small disk samples strained in parallel. Results from these par allel, mini-disk experiments lead to Arrhenius behavior with activation energy consistent with values commonly observed for elastomers, allowing more confident extrapolated predictions. In addition, excellent correlation is noted between the CSR force decay and the oxygen consumption rate, consistent with the expectation that oxidative scission processes dominate the CSR results. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Gillen, KT (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 28 TC 3 Z9 3 U1 1 U2 3 PU WILEY-V C H VERLAG GMBH PI BERLIN PA MUHLENSTRASSE 33-34, D-13187 BERLIN, GERMANY SN 0003-3146 J9 ANGEW MAKROMOL CHEM JI Angew. Makromol. Chem. PD DEC PY 1998 VL 262 BP 83 EP 92 PG 10 WC Polymer Science SC Polymer Science GA 154XD UT WOS:000077914600009 ER PT J AU Gardener, BBM de Bruijn, FJ AF Gardener, BBM de Bruijn, FJ TI Detection and isolation of novel rhizopine-catabolizing bacteria from the environment SO APPLIED AND ENVIRONMENTAL MICROBIOLOGY LA English DT Article ID PSEUDOMONAS-PUTIDA; RHIZOBIUM-MELILOTI; CARBON SOURCE; PLANTS; POPULATIONS; SALICYLATE; STRAINS; GROWTH; OPINES; COEXISTENCE AB Microbial rhizopine-catabolizing (Moc) activity was detected in serial dilutions of sail and rhizosphere washes, The activity observed generally ranged between 10(6) and 10(7) catabolic units per g, and the numbers of nonspecific culture-forming units were found to be approximately 10 times higher. A diverse set of 37 isolates was obtained by enrichment on scyllo-inosamine-containing media. However, none of the bacteria that were isolated were found to contain DNA sequences homologous to the known mocA, mocB, and mocC genes of Sinorhizobium meliloti L5-30. Twenty-one of the isolates could utilize an SI preparation as the sole carbon and nitrogen source for growth. Partial sequencing of 16S ribosomal DNAs (rDNAs) amplified From these strains indicated that five distinct bacterial genera (Arthrobacter, Sinorhizobium, Pseudomonas, Aeromonas, and Alcaligenes) were represented in this set. Only 6 of these 21 isolates could catabolize 3-O-methyl-scyllo-inosamine under standard assay conditions. Two of these, strains D1 and R3, were found to have 16S rDNA sequences very similar to those of Sinorhizobium meliloti, However, these strains are not symbiotically effective on Medicago sativa, and DNA sequences homologous to the nodB and nodC genes were not detected in strains D1 and RS by Southern hybridization analysis. C1 Michigan State Univ, DOE, Plant Res Lab, E Lansing, MI 48824 USA. Michigan State Univ, Dept Bot & Plant Pathol, E Lansing, MI 48824 USA. Michigan State Univ, Dept Microbiol, E Lansing, MI 48824 USA. Michigan State Univ, NSF Ctr Microbial Ecol, E Lansing, MI 48824 USA. RP de Bruijn, FJ (reprint author), Michigan State Univ, DOE, Plant Res Lab, E Lansing, MI 48824 USA. EM debruijn@pilot.msu.edu NR 35 TC 12 Z9 12 U1 1 U2 2 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1325 MASSACHUSETTS AVENUE, NW, WASHINGTON, DC 20005-4171 USA SN 0099-2240 J9 APPL ENVIRON MICROB JI Appl. Environ. Microbiol. PD DEC PY 1998 VL 64 IS 12 BP 4944 EP 4949 PG 6 WC Biotechnology & Applied Microbiology; Microbiology SC Biotechnology & Applied Microbiology; Microbiology GA 145XB UT WOS:000077396700047 ER PT J AU Tejnil, E Goldberg, KA Bokor, J AF Tejnil, E Goldberg, KA Bokor, J TI Phase effects owing to multilayer coatings in a two-mirror extreme-ultraviolet Schwarzschild objective SO APPLIED OPTICS LA English DT Article ID X-RAYS; TRANSMISSION; REFLECTION AB The aberrations of a multilayer-coated reflective Schwarzschild objective, which are influenced both by mirror surface profiles and by multilayer coatings, are evaluated with a phase-shifting point diffraction interferometer operating in the extreme ultraviolet. Using wave-front measurements at multiple wavelengths near 13.4 nm, we observed chromatic aberrations and wavelength-dependent transmission changes that were due to molybdenum-silicon multilayer coatings. The effects of chromatic vignetting due to limited multilayer reflection passbands on the imaging performance of the Schwarzschild optic are considered. The coating characteristics extracted from the interferometry data on the two-mirror optical system are compared with previously reported coating properties measured on individual mirror substrates. (C) 1998 Optical Society of America. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Xray Opt, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Elect Engn & Comp Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. RP Tejnil, E (reprint author), Intel Corp, Santa Clara, CA 95052 USA. RI Bokor, Jeffrey/A-2683-2011 NR 16 TC 5 Z9 6 U1 1 U2 3 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0003-6935 J9 APPL OPTICS JI Appl. Optics PD DEC 1 PY 1998 VL 37 IS 34 BP 8021 EP 8029 DI 10.1364/AO.37.008021 PG 9 WC Optics SC Optics GA 141XB UT WOS:000077168600014 PM 18301694 ER PT J AU Meriaudeau, F Downey, TR Passian, A Wig, A Ferrell, TL AF Meriaudeau, F Downey, TR Passian, A Wig, A Ferrell, TL TI Environment effects on surface-plasmon spectra in gold-island films potential for sensing applications SO APPLIED OPTICS LA English DT Article ID OPTICAL-PROPERTIES; SILVER SPHEROIDS; PARTICLES; ABSORBANCE; SUBSTRATE; MODES AB The effects of the local dielectric environment on the surface-plasmon resonances of annealed gold-island films as a potential for sensing applications are studied experimentally and modeled theoretically. Gold-island films were annealed at 600 degrees C to produce spheroidal shape particles that exhibit well-resolved resonances in polarized, angle-resolved, absorption spectra. These resonances are shifted in different amounts by the depolarization effect of the surrounding medium (liquids with various refraction indices). Cross-section calculations based on nonretarded, single-particle, dielectric interaction for these various configurations are presented and are found to be in good agreement with the experimental observations. The results show an interesting potential for biosensing or environmental monitoring applications. (C) 1998 Optical Society of America. C1 Lab Elect Informat & Image, F-71200 Le Creusot, France. Oak Ridge Natl Lab, Div Life Sci, Photometr Grp, Oak Ridge, TN 37830 USA. Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. RP Meriaudeau, F (reprint author), Lab Elect Informat & Image, 12 Rue Fonderie, F-71200 Le Creusot, France. EM fabrice@hsrhp.hsr.ornl.gov NR 19 TC 47 Z9 47 U1 1 U2 8 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0003-6935 J9 APPL OPTICS JI Appl. Optics PD DEC 1 PY 1998 VL 37 IS 34 BP 8030 EP 8037 DI 10.1364/AO.37.008030 PG 8 WC Optics SC Optics GA 141XB UT WOS:000077168600015 PM 18301695 ER PT J AU Prochnow, E Edwards, DF AF Prochnow, E Edwards, DF TI The precision hand polishing of BBO and LBO SO APPLIED OPTICS LA English DT Article ID CRYSTAL; LIB3O5 AB A hand polishing method for generating stain-free surfaces for BBO and LBO having surface figures of 1/10th wave or better, parallelisms of less than 1 are s and surface roughness of 10 Angstrom RMS or less is described. Barium metaborate (BaB2O4, BBO) and lithium triborate (LiB3O5, LBO) are nonlinear crystals characterized by a wide transparency range, small birefringence, a moderate nonlinear optical coefficient, and a high optical damage threshold.(1-3) The realization of these properties depends, to a great extent, on the ability to fabricate quality surfaces for these crystals. The focus of this note is the precise hand polishing of these crystals. C1 Univ Calif Lawrence Livermore Natl Lab, Opt Sci & Engn Grp, Livermore, CA 94550 USA. RP Prochnow, E (reprint author), Univ Calif Lawrence Livermore Natl Lab, Opt Sci & Engn Grp, Livermore, CA 94550 USA. NR 4 TC 6 Z9 10 U1 1 U2 6 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0003-6935 J9 APPL OPTICS JI Appl. Optics PD DEC 1 PY 1998 VL 37 IS 34 BP 8130 EP 8131 PG 2 WC Optics SC Optics GA 141XB UT WOS:000077168600028 ER PT J AU Kolsky, KL Mausner, LF AF Kolsky, KL Mausner, LF TI Production of no-carrier-added Be-7 from target cooling water SO APPLIED RADIATION AND ISOTOPES LA English DT Article AB Beryllium-7, a monoenergetic photon emitter, is present as a by-product in a no carrier-added (NCA) form at the BLIP from proton activation of the water which is used to cool targets. This report describes its recovery and purification. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Brookhaven Natl Lab, Dept Med, Upton, NY 11973 USA. RP Kolsky, KL (reprint author), Brookhaven Natl Lab, Dept Med, POB 5000,Bldg 801, Upton, NY 11973 USA. NR 7 TC 1 Z9 1 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0969-8043 J9 APPL RADIAT ISOTOPES JI Appl. Radiat. Isot. PD DEC PY 1998 VL 49 IS 12 BP 1489 EP 1492 DI 10.1016/S0969-8043(98)00035-9 PG 4 WC Chemistry, Inorganic & Nuclear; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Chemistry; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 112KR UT WOS:000075494300005 ER PT J AU Kolsky, KL Joshi, V Mausner, LF Srivastava, SC AF Kolsky, KL Joshi, V Mausner, LF Srivastava, SC TI Radiochemical purification of no-carrier-added scandium-47 for radioimmunotherapy SO APPLIED RADIATION AND ISOTOPES LA English DT Article ID MONOCLONAL-ANTIBODIES; RADIONUCLIDES; SELECTION; Y-90 AB A procedure, adaptable to large-scale remote operation, was developed to purify no-carrier-added (NCA) (SC)-S-47 from irradiated Ti targets. Methods based on extraction chromatography and cation-exchange chromatography were compared. Results of this comparison led to the development of an optimized procedure based on cation-exchange with Dowex AG 50W-X4 and Sc-47 elution with HCl/HF. This method gave 90-97% overall Sc-47 recovery, with a Ti separation factor greater than 2.4 x 10(-5), and specific activities greater than or equal to 0.9 GBq mu g(-1). Use of the Sc-47 product, for labeling monoclonal antibodies, resulted in consistent labeling yields of greater than or equal to 90%. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Brookhaven Natl Lab, Dept Med, Upton, NY 11973 USA. RP Kolsky, KL (reprint author), Brookhaven Natl Lab, Dept Med, Upton, NY 11973 USA. NR 34 TC 35 Z9 35 U1 2 U2 10 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0969-8043 J9 APPL RADIAT ISOTOPES JI Appl. Radiat. Isot. PD DEC PY 1998 VL 49 IS 12 BP 1541 EP 1549 DI 10.1016/S0969-8043(98)00016-5 PG 9 WC Chemistry, Inorganic & Nuclear; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Chemistry; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 112KR UT WOS:000075494300015 PM 9745690 ER PT J AU Schoonover, JR Weesner, F Havrilla, GJ Sparrow, M Treado, P AF Schoonover, JR Weesner, F Havrilla, GJ Sparrow, M Treado, P TI Integration of elemental and molecular imaging to characterize heterogeneous inorganic materials SO APPLIED SPECTROSCOPY LA English DT Article DE integrated spectroscopy; chemical imaging; microscopy; micro-X-ray fluorescence; micro-Raman; micro-infrared; LCTF; materials ID PLANE ARRAY DETECTION; RAMAN MICROSCOPY; SPECTRA AB Spatially resolved elemental and molecular information has been obtained for complex inorganic mixed-phase systems, including plutonium-contaminated ash samples, with the use of micro-X-ray fluorescence (MXRF), micro-Raman, and micro-infrared imaging spectroscopies. Approaches for spatially guided analysis and the combination of multispectral data sets to improve assignment of chemical composition are discussed for two heterogeneous materials. This novel integrated experimental approach provides the advantages of a very small sample size and the ability to correlate elemental analysis with molecular functional group analysis for species identification, as well as insight into chemical interactions in complex matrices. C1 Univ Calif Los Alamos Natl Lab, Chem Sci & Technol Div, Los Alamos, NM 87545 USA. Univ Calif Los Alamos Natl Lab, Div Nucl Mat Technol, Los Alamos, NM 87545 USA. Univ Pittsburgh, Dept Chem, Pittsburgh, PA 15208 USA. Chemlcon Inc, Pittsburgh, PA 15208 USA. RP Schoonover, JR (reprint author), Univ Calif Los Alamos Natl Lab, Chem Sci & Technol Div, POB 1663, Los Alamos, NM 87545 USA. NR 21 TC 28 Z9 29 U1 1 U2 5 PU SOC APPLIED SPECTROSCOPY PI FREDERICK PA 201B BROADWAY ST, FREDERICK, MD 21701 USA SN 0003-7028 J9 APPL SPECTROSC JI Appl. Spectrosc. PD DEC PY 1998 VL 52 IS 12 BP 1505 EP 1514 DI 10.1366/0003702981943202 PG 10 WC Instruments & Instrumentation; Spectroscopy SC Instruments & Instrumentation; Spectroscopy GA 155AW UT WOS:000077924500003 ER PT J AU Gunn, JE Carr, M Rockosi, C Sekiguchi, M Berry, K Elms, B de Haas, E Ivezic, Z Knapp, G Lupton, R Pauls, G Simcoe, R Hirsch, R Sanford, D Wang, S York, D Harris, F Annis, J Bartozek, L Boroski, W Bakken, J Haldeman, M Kent, S Holm, S Holmgren, D Petravick, D Prosapio, A Rechenmacher, R Doi, M Fukugita, M Shimasaku, K Okada, N Hull, C Siegmund, W Mannery, E Blouke, M Heidtman, D Schneider, D Lucinio, R Brinkman, J AF Gunn, JE Carr, M Rockosi, C Sekiguchi, M Berry, K Elms, B de Haas, E Ivezic, Z Knapp, G Lupton, R Pauls, G Simcoe, R Hirsch, R Sanford, D Wang, S York, D Harris, F Annis, J Bartozek, L Boroski, W Bakken, J Haldeman, M Kent, S Holm, S Holmgren, D Petravick, D Prosapio, A Rechenmacher, R Doi, M Fukugita, M Shimasaku, K Okada, N Hull, C Siegmund, W Mannery, E Blouke, M Heidtman, D Schneider, D Lucinio, R Brinkman, J TI The Sloan Digital Sky Survey photometric camera SO ASTRONOMICAL JOURNAL LA English DT Article DE astrometry; atlases; catalogs; cosmology : observations; instrumentation : detectors; instrumentation : photometers; surveys ID MOSAIC CAMERA; TELESCOPE; SYSTEM AB We have constructed a large-format mosaic CCD camera for the Sloan Digital Sky Survey. The camera consists of two arrays, a photometric array that uses 30 2048 x 2048 SITe/Tektroniu CCDs (24 mu m pixels) with an effective imaging area of 720 cm(2) and an astrometric array that uses 24 400 x 2048 CCDs with the same pixel size, which will allow us to tie bright astrometric standard stars to the objects imaged in the photometric camera. The instrument will be used to carry out photometry essentially simultaneously in five color bands spanning the range accessible to silicon detectors on the ground in the time-delay-and-integrate (TDI) scanning mode. The photometric detectors are arrayed in the focal plane in six columns of five chips each such that two scans cover a filled stripe 2." 5 wide. This paper presents engineering and technical details of the camera. C1 Princeton Univ, Dept Astrophys Sci, Princeton, NJ 08544 USA. Princeton Univ Observ, Princeton, NJ 08544 USA. Univ Chicago, Ctr Astron & Astrophys, Chicago, IL 60637 USA. USN Observ, Flagstaff, AZ 86002 USA. Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Tokyo, Sch Sci, Dept Astron, Bunkyo Ku, Tokyo 113, Japan. Natl Astron Observ, Tokyo 181, Japan. Univ Washington, Dept Astron, Seattle, WA 98195 USA. Sci Imaging Technol Inc, Beaverton, OR USA. Penn State Univ, Dept Astron & Astrophys, Davey Lab 525, University Pk, PA 16802 USA. Apache Point Observ, Sunspot, NM 88349 USA. RP Gunn, JE (reprint author), Princeton Univ, Dept Astrophys Sci, Peyton Hall, Princeton, NJ 08544 USA. NR 20 TC 1213 Z9 1215 U1 1 U2 22 PU UNIV CHICAGO PRESS PI CHICAGO PA 5801 S ELLIS AVENUE, CHICAGO, IL 60637 USA SN 0004-6256 J9 ASTRON J JI Astron. J. PD DEC PY 1998 VL 116 IS 6 BP 3040 EP 3081 DI 10.1086/300645 PG 42 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 147RQ UT WOS:000077512000036 ER PT J AU Abel, T Stebbins, A Anninos, P Norman, ML AF Abel, T Stebbins, A Anninos, P Norman, ML TI First structure formation. II. Cosmic string plus hot dark matter models SO ASTROPHYSICAL JOURNAL LA English DT Article DE cosmic strings; cosmology : theory; elementary particles; hydrodynamics ID HYDROGEN MOLECULES; NEUTRINOS; OBJECTS; SCHEME; WAKES AB We examine the structure of baryonic wakes in the cosmological fluid that would form behind grand unified theory-scale cosmic strings at early times (redshifts z greater than or similar to 100) in a neutrino-dominated universe. We show, using simple analytical arguments as well as one- and two-dimensional hydrodynamical simulations, that these wakes will not be able to form interesting cosmological objects before the neutrino component collapses. The width of the baryonic wakes (less than or similar to 10 kpc comoving) is smaller than the scale of wiggles on the strings and is probably not enhanced by the wiggliness of the string network. C1 Univ Illinois, Natl Ctr Supercomp Applicat, Lab Computat Astrophys, Urbana, IL 61801 USA. Max Planck Inst Astrophys, D-85748 Garching, Germany. Fermi Natl Accelerator Lab, NASA, Astrophys Ctr, Batavia, IL 60510 USA. RP Abel, T (reprint author), Univ Illinois, Natl Ctr Supercomp Applicat, Lab Computat Astrophys, 405 N Mathews Ave, Urbana, IL 61801 USA. EM abel@mpa-garching.mpg.de; stebbins@fnal.gov; panninos@ncsa.uiuc.edu; norman@ncsa.uiuc.edu NR 33 TC 7 Z9 7 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD DEC 1 PY 1998 VL 508 IS 2 BP 530 EP 534 DI 10.1086/306413 PN 1 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152MC UT WOS:000077780500007 ER PT J AU Hunter, JH Whitaker, RW Lovelace, RVE AF Hunter, JH Whitaker, RW Lovelace, RVE TI Stability of interfaces with self-gravity, relative flow, and B field SO ASTROPHYSICAL JOURNAL LA English DT Article DE hydrodynamics; instabilities; ISM : clouds; MHD; stars : formation ID KELVIN-HELMHOLTZ; INSTABILITIES AB Observations with the Hubble Space Telescope (Hester et al.) of spectacular "fingers" or "elephant trunks" of gas protruding from a large star-forming cloud in the Eagle Nebula stimulate renewed interest in the stability of interfaces between different media in molecular clouds. Instability and nonlinear growth of crenelations of interfaces can lead to mass concentrations that in turn lead to star formation. In an earlier study of the stability of interfaces, we took into account the important physical effects-the different densities and temperatures of the media, the relative motion (Kelvin-Helmholtz instability), the gravitational acceleration perpendicular to the interface (Rayleigh-Taylor instability), and self-gravity. A new self-gravitational instability of an interface was found that was independent of the wavelength of the perturbation. At short wavelengths, the perturbations are essentially distortional, but compression becomes important as the Jeans length is approached from below. The e-folding time for the instability is comparable with the free-fall collapse time for the denser fluid. In the present work, we generalize our earlier theory in two ways: by including ordered magnetic fields parallel to the interface, and by examining the stability of long cylindrical interfaces. We show that dynamically important magnetic fields in the media can quench instabilities if the fields are oriented in different directions (that is, crossed); however, for astronomically plausible geometries in which the fields are closer to being parallel, but of different strengths in the two media, instabilities are free to grow in directions normal to the fields. A cylindrical interface between an interior medium of density rho(1) and an exterior medium of density rho(2) provides a model for the long filaments of dense gas observed in some molecular clouds. We show that such an interface with rho(1) > rho(2) is stable to ''kink modes" but unstable to "sausage modes" owing to self-gravity for long axial wavelengths, lambda(z) > 3.8d, where d is the diameter of the cylinder. This instability will tend to form prolate ellipsoidal density concentrations aligned with the cylinder axis. C1 Univ Florida, Dept Astron, Gainesville, FL 32611 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Cornell Univ, Dept Astron, Ithaca, NY 14853 USA. RP Hunter, JH (reprint author), Univ Florida, Dept Astron, POB 112005, Gainesville, FL 32611 USA. NR 5 TC 9 Z9 9 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD DEC 1 PY 1998 VL 508 IS 2 BP 680 EP 689 PN 1 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152MC UT WOS:000077780500023 ER PT J AU Link, B Franco, LM Epstein, RI AF Link, B Franco, LM Epstein, RI TI Starquake-induced magnetic field and torque evolution in neutron stars SO ASTROPHYSICAL JOURNAL LA English DT Article DE dense matter; magnetic fields; pulsars : individual (Crab); stars : magnetic fields; stars : neutron; stars : rotation ID CRAB PULSAR; VELA PULSAR; GLITCHES; REGION AB The persistent increases in spin-down rate (offsets) seen to accompany glitches in the Crab and other pulsars suggest increases in the spin-down torque. We interpret these offsets as due to starquakes occurring as the star spins down and the rigid crust becomes less oblate. We study the evolution of strain in the crust, the initiation of starquakes, and possible consequences for magnetic field and torque evolution. Crust cracking occurs as equatorial material shears under the compressive forces arising from the star's decreasing circumference and as matter moves to higher latitudes along a fault inclined to the equator. A starquake is most likely to originate near one of the two points on the rotational equator farthest from the magnetic poles. The material breaks along a fault approximately aligned with the magnetic poles. We suggest that the observed offsets come about when a starquake perturbs the star's mass distribution, producing a misalignment of the angular momentum and spin axes. Subsequently, damped precession to a new rotational state increases the angle a between the rotation and magnetic axes. The resulting increase in external torque appears as a permanent increase in the spin-down rate. Repeated starquakes would continue to increase a, making the pulsar more of an orthogonal rotator. C1 Montana State Univ, Dept Phys, Bozeman, MT 59717 USA. Univ Chicago, Chicago, IL 60637 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Link, B (reprint author), Montana State Univ, Dept Phys, Bozeman, MT 59717 USA. NR 21 TC 30 Z9 30 U1 2 U2 3 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD DEC 1 PY 1998 VL 508 IS 2 BP 838 EP 843 DI 10.1086/306457 PN 1 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152MC UT WOS:000077780500039 ER PT J AU Webber, WR Kish, JC Rockstroh, JM Cassagnou, Y Legrain, R Soutoul, A Testard, O Tull, C AF Webber, WR Kish, JC Rockstroh, JM Cassagnou, Y Legrain, R Soutoul, A Testard, O Tull, C TI Production cross sections of fragments from beams of 400-650 MeV per nucleon Be-9, B-11, C-12, N-14, N-15, O-16, Ne-20, Ne-22, Fe-56, and Ni-58 nuclei interacting in a liquid hydrogen target. I. Charge changing and total cross sections SO ASTROPHYSICAL JOURNAL LA English DT Article DE atomic process; cosmic rays; methods : laboratory ID COSMIC-RAY PROPAGATION; RELATIVISTIC NUCLEI; CARBON TARGETS; NICKEL PROJECTILES; LOW-ENERGY; HELIUM; HELIOSPHERE; GALAXY; NEON AB We have measured the charge changing cross sections from 10 individual beams of isotopes from 8 different nuclei between Be and Ni which were accelerated to energies from 400-650 MeV nucleon(-1) at the SATURNE Accelerator in France in 1993 and 1994. These nuclei interacted in a 1.52 g cm(-2) thick liquid hydrogen target and the fragments were observed. This is the first use of a pure hydrogen target to measure cross sections that has a thickness approximating the amount of hydrogen traversed by cosmic rays in our Galaxy. Several of the beam charges such as Be-9, B-11, N-15, and Ne-22 have not had their fragmentation cross sections measured previously. The cross sections from the C-12, N-14, O-16, Ne-20, Fe-56, and Ni-58 beams are compared with earlier measurements by our group using a CH2 - C target subtraction technique to determine the hydrogen cross sections. The overall agreement between the new measurements and the earlier measurements using CH2 - C subtraction is excellent with a systematic consistency between measurements of 3%-5%. Using these new cross sections the predictions of both the B/C and Z = (21-23)/Fe ratios at similar to 1 GeV nucleon(-1) now agree with HEAO measurements to similar to 1%-2%, thus obviating the need for truncation of the exponential path length distribution path length distribution that is expected from uniform propagation models. Also, these new charge changing cross sections along with the isotopic cross sections reported in paper two of this series, define the production of cosmic-ray beryllium and boron nuclei in the galaxy and also the secondary isotopes Be-10, C-13, N-14, N-15, O-18, and all of the Fe secondary isotopes to a level of precision of 3%-5% or better. These cross sections are important for determining the abundance of these rare isotopes and others in the cosmic-ray sources as well as tracing the detailed propagation history of cosmic rays in the Galaxy. These measurements also provide high precision cross sections for the study of the nuclear physics of the interaction process. C1 New Mexico State Univ, Dept Astron, Las Cruces, NM 88003 USA. Spectra Res Inc, Portsmouth, NH 03820 USA. CENS, Serv Astrophys, Gif Sur Yvette, France. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Webber, WR (reprint author), New Mexico State Univ, Dept Astron, POB 30001, Las Cruces, NM 88003 USA. NR 24 TC 36 Z9 36 U1 0 U2 7 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD DEC 1 PY 1998 VL 508 IS 2 BP 940 EP 948 DI 10.1086/306445 PN 1 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152MC UT WOS:000077780500050 ER PT J AU Webber, WR Kish, JC Rockstroh, JM Cassagnou, Y Legrain, R Soutoul, A Testard, O Tull, C AF Webber, WR Kish, JC Rockstroh, JM Cassagnou, Y Legrain, R Soutoul, A Testard, O Tull, C TI Production cross sections of fragments from beams of 400-650 MeV per nucleon Be-9, B-11, C-12, N-14, N-15, O-16, Ne-20, Ne-22, Fe-56, and Ni-58 nuclei interacting in a liquid hydrogen target. II. Isotopic cross sections of fragments SO ASTROPHYSICAL JOURNAL LA English DT Article DE atomic processes; cosmic rays; methods : laboratory ID RELATIVISTIC NUCLEI; CARBON TARGETS; HELIUM; CHARGE; ENERGY AB We have measured the isotopic cross sections of 130 secondary fragmentation isotopes from 10 different beam nuclei from Be-9 to Ni-58 that were accelerated to between 400 and 650 MeV nucleon(-1) at the SATURNE Accelerator in France in 1993 and 1994. These beam nuclei interacted in a 1.52 g cm(-2) thick liquid hydrogen target, and the isotopic fragments were observed. This is the first use of a pure hydrogen target with a thickness approximating the amount of hydrogen traversed by cosmic rays in our Galaxy to measure cross sections. Several of the beam charges such as Be-9, B-11, N-15, and Ne-22 have not had their fragmentation cross sections measured previously. The isotopic cross sections from the C-12, N-14, O-16, Ne-20, Fe-56, and Ni-58 beam interactions are compared with earlier measurements by our group using a CH2-C target subtraction technique to determine the hydrogen cross sections. The overall agreement between the new measurements and the earlier measurements using a C-2-C target subtraction is excellent with a systematic consistency between measurements similar to 3%-5%. These new isotopic cross sections define the Galactic production of the secondary isotopes Be-10, B-10, B-11, C-13, N-14, N-15, and O-18 as well as Fe and Ni secondary decay isotopes from Cl to Co to a level of precision of similar to 3%-5%. These cosmic-ray isotopes are important for understanding the nucleosynthesis in the cosmic-ray sources as well as tracing the detailed propagation history of cosmic rays in the Galaxy. C1 New Mexico State Univ, Dept Astron, Las Cruces, NM 88003 USA. Spectra Res Inc, Portsmouth, NH 03820 USA. CENS, Serv Astrophys, Gif Sur Yvette, France. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Webber, WR (reprint author), New Mexico State Univ, Dept Astron, POB 30001, Las Cruces, NM 88003 USA. NR 17 TC 39 Z9 39 U1 0 U2 4 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD DEC 1 PY 1998 VL 508 IS 2 BP 949 EP 958 DI 10.1086/306446 PN 1 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 152MC UT WOS:000077780500051 ER PT J AU Lenz, DD Newberg, HJ Rosner, R Richards, GT Stoughton, C AF Lenz, DD Newberg, HJ Rosner, R Richards, GT Stoughton, C TI Photometric separation of stellar properties using SDSS filters SO ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES LA English DT Article DE galaxies : photometry; surveys ID DIGITAL SKY SURVEY; SPECTROPHOTOMETRY; CATALOG AB Using synthetic photometry of Kurucz model spectra, we explore the colors of stars as a function of temperature, metallicity, and surface gravity with Sloan Digital Sky Survey (SDSS) filters, u'g'r'i'z'. The synthetic colors show qualitative agreement with the few published observations in these filters. We find that the locus of synthetic stars is basically two-dimensional for 4500 < T < 8000 K, which precludes simultaneous color separation of the three basic stellar characteristics we consider. Colors including u' contain the most information about normal stellar properties; measurements in this filter are also important for selecting white dwarfs. We identify two different subsets of the locus in which the loci separate by either metallicity or surface gravity. For 0.5 < g' - r' < 0.8 (corresponding roughly to G stars), the locus separates by metallicity; for photometric error of a few percent, we estimate metallicity to within similar to 0.5 dex in this range. In the range -0.15 < g' - r' < 0.00 (corresponding roughly to A stars), the locus shows separation by surface gravity. In both cases, we show that it is advantageous to use more than two colors when determining stellar properties by color. Strategic observations in SDSS filters are required to resolve the source of a similar to 5% discrepancy between synthetic colors of Gunn-Stryker stars, Kurucz models, and external. determinations of the metallicities and surface gravities. The synthetic star colors can be used to investigate the properties of any normal star and to construct analytic expressions for the photometric prediction of stellar properties in special cases. C1 Univ Chicago, Dept Astron & Astrophys, Chicago, IL 60637 USA. Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. RP Lenz, DD (reprint author), Univ Chicago, Dept Astron & Astrophys, 5640 S Ellis Ave, Chicago, IL 60637 USA. NR 17 TC 73 Z9 73 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0067-0049 J9 ASTROPHYS J SUPPL S JI Astrophys. J. Suppl. Ser. PD DEC PY 1998 VL 119 IS 2 BP 121 EP 140 DI 10.1086/313155 PG 20 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 150VW UT WOS:000077687300001 ER PT J AU Van Dop, H Addis, R Fraser, G Girardi, F Graziani, G Inoue, Y Kelly, N Klug, W Kulmala, A Nodop, K Pretel, J AF Van Dop, H Addis, R Fraser, G Girardi, F Graziani, G Inoue, Y Kelly, N Klug, W Kulmala, A Nodop, K Pretel, J TI ETEX: A European tracer experiment; Observations, dispersion modelling and emergency response SO ATMOSPHERIC ENVIRONMENT LA English DT Article ID ATMOSPHERIC DISPERSAL; CHERNOBYL ACCIDENT; SIMULATION; RELEASE; AIR AB In Autumn, 1994, two releases of perfluorocarbon tracers from north-east France were tracked across northern Europe using a network of 168 ground stations with limited airborne sampling support. Simulating an emergency response situation, modellers from 20 countries reported their long-range dispersion predictions, initially within a few hours of the release and then over the coming days in line with the evolving meteorological data. Subsequent comparison of the predictions with the environmental results showed model performance varying from good, for the conditions of the first release in the majority of cases, to unsatisfactory for the second release in all cases. The experimental database now established represents a unique tool for investigating the effectiveness of future model developments. The papers in this special issue reflect the major scientific results. (C) 1998 Published by Elsevier Science Ltd. All rights reserved. C1 Univ Utrecht, Inst Marine & Atmospher Res, NL-3508 TA Utrecht, Netherlands. Savannah River Technol Ctr, Environm Transport Grp, Aiken, SC 29808 USA. CEC, L-2920 Luxembourg, Luxembourg. Commiss European Communities, Joint Res Ctr, Inst Environm, I-21020 Ispra, Va, Italy. Int Atom Energy Agcy, Radiat Safety Sect, A-1400 Vienna, Austria. Commiss European Communities, B-1049 Brussels, Belgium. TH Darmstadt, Inst Meteorol, D-6100 Darmstadt, Germany. World Meteorol Org, CH-2300 Geneva 2, Switzerland. Czech Hydrometeorol Inst, Air Protect Div, Prague 14306, Czech Republic. RP Van Dop, H (reprint author), Univ Utrecht, Inst Marine & Atmospher Res, POB 80005, NL-3508 TA Utrecht, Netherlands. NR 20 TC 42 Z9 43 U1 0 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1352-2310 J9 ATMOS ENVIRON JI Atmos. Environ. PD DEC PY 1998 VL 32 IS 24 BP 4089 EP 4094 DI 10.1016/S1352-2310(98)00248-9 PG 6 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA 140ZN UT WOS:000077118300001 ER PT J AU Straume, AG Dietz, RN Koffi, EN Nodop, K AF Straume, AG Dietz, RN Koffi, EN Nodop, K TI Perfluorocarbon background concentrations in Europe SO ATMOSPHERIC ENVIRONMENT LA English DT Article DE perfluorocarbons; tracer release; background concentrations; long-range transport AB Five studies of the background level of several perfluorocarbon compounds in Europe are here presented together with measurements from the European Tracer Experiment (ETEX). The tracers used during the two ETEX tracer releases were the perfluorocarbons (PFCs); perfluoromethylcyclohexane (C7F14, PMCH) and perfluoromethylcyclopentane (C6F12, PMCP). Their background concentrations were detected by using both passive and active sampling techniques, to define the spatial and temporal variation of the PFCs over Europe. Also the background Variations of four isomers of the PFC compound perfluorodimethylcyclohexane (C8F16, PDCH) were studied. The results were compared to other PFC tracer studies in the U.S.A. and Europe. The mean and median values of the measured PFCs were found to vary slightly and randomly in space and time. They were found to be higher and to have a larger standard deviation than the measurements from the American studies. The background concentrations were still found to be low and stable enough for PFCs to be highly suitable for use in tracer studies. The following concentrations were found: PMCP; 4.6 +/- 0.3 fl l(-1), PMCH: 4.6 +/- 0.8 fl l(-1), ocPDCH: 0.96 +/- 0.33 fl l(-1), mtPDCH: 9.3 +/- 0.8 fl l(-1), mcPDCH: 8.8 +/- 0.8 fl l(-1), ptPDCH: 6.1 +/- 0.8 fl l(-1). A study of the correlation between the measured PFC compounds showed a significant correlation between most of the compounds, which indicate that there are no major PFC sources in Europe. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Commiss European Communities, Joint Res Ctr, Inst Environm, I-21020 Ispra, Italy. Brookhaven Natl Lab, Upton, NY 11973 USA. RP Straume, AG (reprint author), Commiss European Communities, Joint Res Ctr, Inst Environm, I-21020 Ispra, Italy. NR 8 TC 17 Z9 18 U1 0 U2 4 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1352-2310 J9 ATMOS ENVIRON JI Atmos. Environ. PD DEC PY 1998 VL 32 IS 24 BP 4109 EP 4122 DI 10.1016/S1352-2310(98)00193-9 PG 14 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA 140ZN UT WOS:000077118300003 ER PT J AU Nasstrom, JS Pace, JC AF Nasstrom, JS Pace, JC TI Evaluation of the effect of meteorological data resolution on Lagrangian particle dispersion simulations using the ETEX experiment SO ATMOSPHERIC ENVIRONMENT LA English DT Article DE Lagrangian stochastic dispersion model; numerical weather prediction models; European tracer experiment; long-range dispersion ID ATMOSPHERIC DISPERSION; OSCILLATIONS; LAYER AB This paper presents results from a series of numerical experiments-designed to evaluate operational long-range dispersion model simulations, and to investigate the effect of different temporal and spatial resolution of meteorological data from numerical weather prediction models on these simulations. Results of Lagrangian particle dispersion simulations of the first tracer release of the European Tracer Experiment (ETEX) are presented and compared with measured tracer concentrations.; The use of analyzed data of higher resolution from the European Center for Medium-Range Weather Forecasts(ECMWF) model produced significantly better agreement between the concentrations predicted with the dispersion model and the ETEX measurements than the use of lower resolution Navy Operational Global Atmospheric Prediction System (NOGAPS) forecast data. Numerical experiments were performed in which the ECMWF model data with lower vertical resolution (4 instead of 7 levels below 500 mb), lower temporal resolution (12 h instead of 6 h intervals),: and lower horizontal resolution (2.5 degrees instead of 0.5 degrees) were used. Degrading the horizontal or temporal resolution of the ECMWF data resulted in decreased accuracy of the dispersion simulations. These results indicate that flow features resolved by the numerical weather prediction model data at approximately 45 km horizontal grid spacing and 6 h time intervals, but not resolved at 225 km spacing and 12 h intervals, made an important contribution to the long-range dispersion. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Univ Calif Lawrence Livermore Natl Lab, Div Atmospher Sci, Livermore, CA 94551 USA. RP Nasstrom, JS (reprint author), Univ Calif Lawrence Livermore Natl Lab, Div Atmospher Sci, Mail Stop L-103,POB 808, Livermore, CA 94551 USA. NR 17 TC 9 Z9 12 U1 0 U2 2 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1352-2310 J9 ATMOS ENVIRON JI Atmos. Environ. PD DEC PY 1998 VL 32 IS 24 BP 4187 EP 4194 DI 10.1016/S1352-2310(98)00180-0 PG 8 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA 140ZN UT WOS:000077118300009 ER PT J AU Hillier, W Messinger, J Wydrzynski, T AF Hillier, W Messinger, J Wydrzynski, T TI Kinetic determination of the fast exchanging substrate water molecule in the S-3 state of photosystem II SO BIOCHEMISTRY LA English DT Article; Proceedings Paper CT Symposium in Honor of Ken Sauer and Mel Klein CY JAN 07-08, 1998 CL UNIV CALIFORNIA, BERKELEY, CA HO UNIV CALIFORNIA ID OXYGEN-EVOLVING COMPLEX; PRESSURE NMR KINETICS; PHOTOSYNTHETIC O2 EVOLUTION; CYTOCHROME-C-OXIDASE; MANGANESE CLUSTER; VARIABLE-TEMPERATURE; S2 STATE; X-RAY; OXIDIZING COMPLEX; MULTILINE SIGNAL AB In a previous communication we showed from rapid isotopic exchange measurements that the exchangeability of the substrate water at the water oxidation catalytic site in the S-3 State undergoes biphasic kinetics although the fast phase could not be fully resolved at that time Flessinger, J., Badger, M., and Wydrzynski, T. (1995) Proc. Natl. Acad. Sci, U.S.A. 92, 3209-3213]. We have since improved the time resolution for these measurements by a further factor of 3 and report here the first detailed kinetics for the fast phase of exchange. First-order exchange kinetics were determined from mass spectrometric measurements of photogenerated O-2 as a function of time after injection of (H2O)-O-18 into spinach thylakoid samples preset in the S-3 State at 10 degrees C. For measurements made at m/e = 34 (i.e., for the mixed labeled O-16,18(2) product), the two kinetic components are observed: a slow component with k(1) = 2.2 +/- 0.1 s(-1) (t(1/2) similar to 315 ms) and a fast component with k(2) = 38 +/- 4 s(-1) (t(1/2) similar to 18 ms). When the isotopic exchange is measured at m/e = 36 (i.e,, for the double labeled O-18,18(2) product), only the slow component (k(1)) is observed, clearly indicating that the substrate water undergoing slow isotopic exchange provides the rate-limiting step in the formation of the double labeled O-18,18(2) product. When the isotopic exchange is measured as a function of temperature, the two kinetic components reveal different temperature dependencies in which k(1) increases by a factor of 10 over the range 0-20 degrees C while k(2) increases by only a factor of 3. Assuming simple Arrhenius behavior, the activation energies are estimated to be 78 +/- 10 kJ mol(-1) for the slow component and 39 +/- 5 kJ mol(-1) for the fast component. The different kinetic components in the O-18 isotopic exchange provide firm evidence that the two substrate water molecules undergo separate exchange processes at two different chemical sites in the S-3 state, prior to the O-2 release step (t(1/2) similar to 1 ms at 20 degrees C). The results are discussed in terms of how the substrate water may be bound at two separate metal sites. C1 Australian Natl Univ, Res Sch Biol Sci, Canberra, ACT 0200, Australia. Univ Calif Berkeley, Lawrence Berkeley Lab, Phys Biosci Div, Berkeley, CA 94720 USA. RP Hillier, W (reprint author), Australian Natl Univ, Res Sch Biol Sci, Canberra, ACT 0200, Australia. EM Hillier@RBS.ANU.EDU.AU; Tom@RSBS.ANU.EDU.AU RI Wydrzynski, Thomas/C-9630-2009 NR 59 TC 87 Z9 88 U1 0 U2 5 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0006-2960 J9 BIOCHEMISTRY-US JI Biochemistry PD DEC 1 PY 1998 VL 37 IS 48 BP 16908 EP 16914 DI 10.1021/bi980756z PG 7 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 144WX UT WOS:000077339600008 PM 9836583 ER PT J AU Ivanchenko, M Zacharieva, S Yaneva, J Zlatanova, J AF Ivanchenko, M Zacharieva, S Yaneva, J Zlatanova, J TI Linker histone binding to superhelical DNA: Electrophoretic and filter binding studies SO BIOCHIMIE LA English DT Article DE filter binding; linker histones; protein-DNA interactions; superhelical DNA; two-dimensional gel electrophoresis ID GLOBULAR DOMAIN; H1; H5; HMG1 AB It has been known for years that linker histones bind preferentially to supercoiled DNA. This preference has been demonstrated by a number of different techniques including deoxyribonucleoprotein electrophoresis, sedimentation, and filter binding under non-competitive conditions. In an attempt to further study this issue, we used one- and two-dimensional electrophoretic gels and filter binding under competitive conditions, with all DNA forms of interest being simultaneously present in the incubation mixture. Comparison between results obtained by the two methods showed that whereas the preference for superhelical molecules was clearly seen in the electrophoretic gels, the filter binding assay failed to reveal this preference. These results reveal limitations to the filter binding technique, which must be borne in mind in studies involving superhelical DNA molecules. (C) Societe francaise de biochimie et biologie moleculaire / Elsevier, Paris. C1 Oregon State Univ, Argonne Natl Lab, Ctr Mech Biol & Biotechnol, Dept Biochem & Biophys, Corvallis, OR 97331 USA. Bulgarian Acad Sci, Inst Expt Pathol, BU-1113 Sofia, Bulgaria. Bulgarian Acad Sci, Inst Mol Biol, BU-1113 Sofia, Bulgaria. RP Zlatanova, J (reprint author), Oregon State Univ, Argonne Natl Lab, Ctr Mech Biol & Biotechnol, Dept Biochem & Biophys, Bldg 202-A253, Corvallis, OR 97331 USA. RI Zlatanova, Jordanka/B-3273-2009 FU FIC NIH HHS [TW00568-02]; NIGMS NIH HHS [GM50276] NR 15 TC 0 Z9 0 U1 0 U2 0 PU EDITIONS SCIENTIFIQUES MEDICALES ELSEVIER PI PARIS CEDEX 15 PA 23 RUE LINOIS, 75724 PARIS CEDEX 15, FRANCE SN 0300-9084 J9 BIOCHIMIE JI Biochimie PD DEC PY 1998 VL 80 IS 12 BP 1031 EP 1034 DI 10.1016/S0300-9084(99)80008-X PG 4 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 197JY UT WOS:000080362700008 PM 9924981 ER PT J AU Jiang, Y Levine, H Glazier, J AF Jiang, Y Levine, H Glazier, J TI Possible cooperation of differential adhesion and chemotaxis in mound formation of Dictyostelium SO BIOPHYSICAL JOURNAL LA English DT Article ID PATTERN-FORMATION; CELL-MOVEMENT; DISCOIDEUM; CAMP; MORPHOGENESIS; SIMULATION; MOTILITY; BEHAVIOR; WAVE AB In the mound stage of Dictyostelium discoideum, pre-stalk cells sort and form a tip at the apex. How this pattern forms is as yet unknown. A cellular level model allows us to simulate both differential cell adhesion and chemotaxis, to show that with differential adhesion only, pre-stalk cells move to the surface of the mound but form no tip. With chemotaxis driven by an outgoing circular wave only, a tip forms but contains both pre-stalk and pre-spore cells. Only for a narrow range of relative strengths between differential adhesion and chemotaxis can both mechanisms work in concert to form a tip containing only pre-stalk cells. The simulations provide a method to determine the processes necessary for patterning and suggest a series of further experiments. C1 Univ Notre Dame, Dept Phys, Notre Dame, IN 46556 USA. Univ Calif San Diego, Dept Phys, La Jolla, CA 92093 USA. RP Jiang, Y (reprint author), Los Alamos Natl Lab, CNLS, POB 1663,MSB258, Los Alamos, NM 87545 USA. EM yi@cnls.lanl.gov; levine@herbie.ucsd.edu; jglazier@rameau.phys.nd.edu RI Levine, Herbert/C-1704-2008 OI Levine, Herbert/0000-0002-8819-9055 NR 32 TC 52 Z9 55 U1 1 U2 4 PU CELL PRESS PI CAMBRIDGE PA 600 TECHNOLOGY SQUARE, 5TH FLOOR, CAMBRIDGE, MA 02139 USA SN 0006-3495 J9 BIOPHYS J JI Biophys. J. PD DEC PY 1998 VL 75 IS 6 BP 2615 EP 2625 PG 11 WC Biophysics SC Biophysics GA 144BZ UT WOS:000077295000002 PM 9826586 ER PT J AU Gallant, J Desbat, B Vaknin, D Salesse, C AF Gallant, J Desbat, B Vaknin, D Salesse, C TI Polarization-modulated infrared spectroscopy and X-ray reflectivity of photosystem II core complex at the gas-water interface SO BIOPHYSICAL JOURNAL LA English DT Article ID REACTION CENTERS; SECONDARY STRUCTURE; LANGMUIR-BLODGETT; GREEN PLANTS; PHOTOSYNTHETIC MEMBRANES; ELECTRON CRYSTALLOGRAPHY; CRYOELECTRON MICROSCOPY; FTIR SPECTROSCOPY; LIQUID SURFACES; CYTOCHROME B559 AB The state of photosystem II core complex (PS II CC) in monolayer at the gas-water interface was investigated using in situ polarization-nodulated infrared reflection absorption spectroscopy and x-ray reflectivity techniques. Two approaches for preparing and manipulating the monolayers were examined and compared. In the first, PS II CC was compressed immediately after spreading at an initial surface pressure of 5.7 mN/m, whereas in the second, the monolayer was incubated for 30 min at an initial surface pressure of 0.6 mN/m before compression, in the first approach, the protein complex maintained its native alpha-helical conformation upon compression, and the secondary structure of PS II CC was found to be stable for 2 h. The second approach resulted in films showing stable surface pressure below 30 mN/m and the presence of large amounts of beta-sheets, which indicated denaturation of PS II CC. Above 30 mN/m, those films suffered surface pressure instability, which had to be compensated by continuous compression. This instability was correlated with the formation of new alpha-helices in the film. Measurements at 4 degrees C strongly reduced denaturation of PS II CC. The x-ray reflectivity studies indicated that the spread film consists of a single protein layer at the gas-water interface. Altogether, this study provides direct structural and molecular information on membrane proteins when spread in monolayers at the gas-water interface. C1 Univ Quebec, Dept Chim Biol, GREIB, Trois Rivieres, PQ G9A 5H7, Canada. Univ Bordeaux 1, Lab Physicochim Mol, F-33405 Talence, France. Iowa State Univ, Dept Phys, Ames Lab, Ames, IA 50011 USA. RP Salesse, C (reprint author), Univ Quebec, Dept Chim Biol, GREIB, 3351 Blvd Forges,CP 500, Trois Rivieres, PQ G9A 5H7, Canada. EM christian_salesse@uqtr.uquebec.ca RI Vaknin, David/B-3302-2009 OI Vaknin, David/0000-0002-0899-9248 NR 53 TC 29 Z9 29 U1 1 U2 1 PU CELL PRESS PI CAMBRIDGE PA 600 TECHNOLOGY SQUARE, 5TH FLOOR, CAMBRIDGE, MA 02139 USA SN 0006-3495 J9 BIOPHYS J JI Biophys. J. PD DEC PY 1998 VL 75 IS 6 BP 2888 EP 2899 PG 12 WC Biophysics SC Biophysics GA 144BZ UT WOS:000077295000026 PM 9826610 ER PT J AU Rege, MA Mills, DR Petersen, JN Sun, YW Yonge, DR Apel, WA AF Rege, MA Mills, DR Petersen, JN Sun, YW Yonge, DR Apel, WA TI Estimation of mass transport parameters in a column packed with BioSep beads SO BIOTECHNOLOGY TECHNIQUES LA English DT Article DE packed column; transport; bioremediation; immobilization matrix AB An approach to estimate the parameters needed to describe the performance of a column packed with BioSep(TM) beads is presented. These parameters, which characterize the transport of materials through the column, have been estimated from experimental residence time distribution (RTD) data using both porous and non-porous beads. A laboratory-scale column was used to obtain the experimental data using several ionic species. C1 Washington State Univ, Ctr Multiphase Environm Res, Pullman, WA 99164 USA. Washington State Univ, Dept Civil & Environm Engn, Pullman, WA 99164 USA. Idaho Natl Engn & Environm Lab, Dept Biotechnol, Idaho Falls, ID 83415 USA. RP Petersen, JN (reprint author), Washington State Univ, Ctr Multiphase Environm Res, Pullman, WA 99164 USA. RI Petersen, James/B-8924-2008; Sun, Yunwei/C-9751-2010 NR 5 TC 1 Z9 1 U1 0 U2 1 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0951-208X J9 BIOTECHNOL TECH JI Biotechnol. Tech. PD DEC PY 1998 VL 12 IS 12 BP 913 EP 918 DI 10.1023/A:1008821730019 PG 6 WC Biochemical Research Methods; Biotechnology & Applied Microbiology SC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology GA 162LT UT WOS:000078348400012 ER PT J AU Gascard, P Lee, G Coulombel, L Auffray, I Lum, M Parra, M Conboy, JG Mohandas, N Chasis, JA AF Gascard, P Lee, G Coulombel, L Auffray, I Lum, M Parra, M Conboy, JG Mohandas, N Chasis, JA TI Characterization of multiple isoforms of protein 4.1R expressed during erythroid terminal differentiation SO BLOOD LA English DT Article ID MEMBRANE SKELETAL PROTEIN-4.1; EPIDERMAL GROWTH-FACTOR; SPECTRIN-ACTIN-BINDING; PRE-MESSENGER-RNA; TRANSFERRIN RECEPTOR; GLYCOPHORIN-C; STRUCTURAL PROTEIN-4.1; ASYNCHRONOUS SYNTHESIS; 4.1-BINDING SITE; ATTACHMENT SITES AB In erythrocytes, 80-kD protein 4.1R regulates critical membrane properties of deformability and mechanical strength. However, previously obtained data suggest that multiple isoforms of protein 4.1, generated by alternative pre-mRNA splicing, are expressed during erythroid differentiation. Erythroid precursors use two splice acceptor sites at the 5' end of exon 2, thereby generating two populations of 4.1 RNA: one that includes an upstream AUG-1 in exon 2' and encodes high molecular weight isoforms, and another that skips AUG-1 in exon 2' and encodes 4.1 by initiation at a downstream AUG-2 in exon 4. To begin an analysis of the complex picture of protein 4.1R expression and function during erythropoiesis, we determined the number and primary structure of 4.1R isoforms expressed in erythroblasts. We used reverse-transcription polymerase chain reaction to amplify and clone full-length coding domains from the population of 4.1R cDNA containing AUG-1 and the population excluding AUG-1. We observed an impressive repertoire of 4.1R isoforms that included 7 major and 11 minor splice variants, thus providing the first definitive characterization of 4.1R primary structures in a single-cell lineage. 4.1R isoforms, transfected into COS-7 cells, distributed to the nucleus, cytoplasm, plasma membrane, and apparent centrosome. We confirmed previous studies showing that inclusion of exon 16 was essential for efficient nuclear localization. Unexpectedly, immunochemical analysis of COS-7 cells transfected with an isoform lacking both AUG-1 and AUG-2 documented that a previously unidentified downstream translation initiation codon located in exon 8 can regulate expression of 4.1R. We speculate that the repertoire of primary structure of 4.1R dictates its distinct binding partners and functions during erythropoiesis. (C) 1998 by The American Society of Hematology. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Biophys & Biomol Struct Dept, Div Life Sci, Berkeley, CA 94720 USA. Lab Hematopiese & Cellules Souches, Villejuif, France. RP Chasis, JA (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Biophys & Biomol Struct Dept, Div Life Sci, Mail Stop 74-157,Cyclotron Rd, Berkeley, CA 94720 USA. FU NIDDK NIH HHS [DK26263, DK32094] NR 75 TC 58 Z9 58 U1 0 U2 1 PU W B SAUNDERS CO PI PHILADELPHIA PA INDEPENDENCE SQUARE WEST CURTIS CENTER, STE 300, PHILADELPHIA, PA 19106-3399 USA SN 0006-4971 J9 BLOOD JI Blood PD DEC 1 PY 1998 VL 92 IS 11 BP 4404 EP 4414 PG 11 WC Hematology SC Hematology GA 142HH UT WOS:000077194300048 PM 9834247 ER PT J AU Willig, TN Perignon, JL Gustavsson, P Gane, P Draptchinskaya, N Testard, H Girot, R Debre, M Stephan, JL Chenel, C Cartron, JP Dahl, N Tchernia, G AF Willig, TN Perignon, JL Gustavsson, P Gane, P Draptchinskaya, N Testard, H Girot, R Debre, M Stephan, JL Chenel, C Cartron, JP Dahl, N Tchernia, G CA DBA Working Grp Societe d'Hematologie d'Immunol TI High adenosine deaminase level among healthy probands of Diamond Blackfan Anemia (DBA) cosegregates with the DBA gene region on chromosome 19q13 SO BLOOD LA English DT Article AB Phenotypic characterization of Diamond Blackfan Anemia (DBA) patients and their relatives was performed in 54 families. Complete blood count, fetal hemoglobin level, erythrocyte i antigen expression, and erythrocyte adenosine deaminase (eADA) activities were quantitated in patients and relatives. eADA was elevated in 28 of 34 transfusion-independent DBA patients, whereas persistence of erythrocyte i antigen was noticed in only 10 of 20 DBA patients. High eADA activities were also found in 14 of 149 healthy family members, allowing us to identify an isolated high eADA phenotype in these families. In contrast, increase in erythrocyte i antigen expression, elevated fetal hemoglobin levels, and macrocytosis were much less frequently noted in nonaffected members of the DBA families studied. Importantly, isolated high eADA phenotype was found to be significantly associated with genetic markers on chromosome 19 that segregate with the DBA phenotype. Isolated high eADA phenotype thus seems to reflect a silent phenotype of DBA in affected families. These findings suggest that elevated eADA activity in unaffected individuals needs to be taken into account during genetic assessment of DBA families and could be used for accurate assessment of mode of inheritance. (C) 1998 by The American Society of Hematology. C1 Assistance Publ Hop Paris, Hop Bicetre, Dept Pediat, Bicetre, France. Assistance Publ Hop Paris, Hop Bicetre, Hematol Lab, Bicetre, France. Fac Med Paris Sud, Paris, France. Hop Necker Enfants Malad, Biochim Lab, Paris, France. Hop Necker Enfants Malad, Unite Hematol & Immunol Pediat, Paris, France. INTS, INSERM, U76, Paris, France. Hop Tenon, Hematol Lab, F-75970 Paris, France. Uppsala Univ, Childrens Hosp, Dept Genet & Pathol, Clin Genet Unit, Uppsala, Sweden. CHU Hop St Etienne, Hop Enfants, Serv Pediat, St Etienne, France. Ctr Hosp Terr Polynesie Francaise, Papeete, Fr Polynesia. RP Willig, TN (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Bldg 74-157,1 Cyclotron Rd, Berkeley, CA 94720 USA. NR 17 TC 26 Z9 26 U1 0 U2 0 PU W B SAUNDERS CO PI PHILADELPHIA PA INDEPENDENCE SQUARE WEST CURTIS CENTER, STE 300, PHILADELPHIA, PA 19106-3399 USA SN 0006-4971 J9 BLOOD JI Blood PD DEC 1 PY 1998 VL 92 IS 11 BP 4422 EP 4427 PG 6 WC Hematology SC Hematology GA 142HH UT WOS:000077194300050 PM 9834249 ER PT J AU Jones, LE Helmberger, DV AF Jones, LE Helmberger, DV TI Earthquake source parameters and fault kinematics in the eastern California shear zone SO BULLETIN OF THE SEISMOLOGICAL SOCIETY OF AMERICA LA English DT Article ID 28 JUNE 1992; BIG-BEAR EARTHQUAKE; LANDERS EARTHQUAKE; SOUTHERN CALIFORNIA; TRANSVERSE RANGES; TERRASCOPE DATA; GARLOCK FAULT; JOSHUA-TREE; STRESS-DROP; BODY WAVES AB Based on waveform data from a profile of aftershocks following the north-south trace of the 28 June 1992 Landers rupture across the Mojave desert, we construct a new velocity model for the Mojave region that features a thin, slow crust. Using this model, we obtain source parameters, including depth and duration, for each of the aftershocks in the profile and, in addition, any significant (M > 3.7) Joshua Tree-Landers aftershock between April 1992 and October 1994 for which coherent TERRAscope data were available. In all, we determine source parameters and stress drops for 45 significant (M-w > 4) earthquakes associated with the Joshua Tree and Landers sequences, using a waveform grid-search algorithm. Stress drops for these earthquakes appear to vary systematically with location, with respect to previous seismic activity, proximity to previous rupture (i.e., with respect to the Landers rupture), and with tectonic province. In general, for areas north of the Pinto Mountain fault, stress drops of aftershocks located off the faults involved with the Landers rupture are higher than those located on the fault, with the exception of aftershocks on the newly recognized Kickapoo (Landers) fault. Stress drops are moderate south of the Pinto Mountain fault, where there is a history of seismic swarms but no single throughgoing fault. In contrast to aftershocks in the eastern Transverse ranges, and related to the 1992 Big Bear, California, sequence, Landers events show no clear relationship between stress drop and depth. Instead, higher stress-drop aftershocks appear to correlate with activity on nascent faults or those that experienced relatively small slip during mainshock rupture. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. CALTECH, Seismol Lab, Pasadena, CA 91125 USA. RP Jones, LE (reprint author), Univ Calif Los Alamos Natl Lab, EES-5,MS-F665, Los Alamos, NM 87545 USA. NR 40 TC 30 Z9 34 U1 1 U2 5 PU SEISMOLOGICAL SOC AMER PI EL CERRITO PA PLAZA PROFESSIONAL BLDG, SUITE 201, EL CERRITO, CA 94530 USA SN 0037-1106 J9 B SEISMOL SOC AM JI Bull. Seismol. Soc. Amer. PD DEC PY 1998 VL 88 IS 6 BP 1337 EP 1352 PG 16 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 154XA UT WOS:000077914300002 ER PT J AU Beresnev, IA Atkinson, GM Johnson, PA Field, EH AF Beresnev, IA Atkinson, GM Johnson, PA Field, EH TI Stochastic finite-fault modeling of ground motions from the 1994 Northridge, California, earthquake. II. Widespread nonlinear response at soil sites SO BULLETIN OF THE SEISMOLOGICAL SOCIETY OF AMERICA LA English DT Article ID LOMA-PRIETA EARTHQUAKE; PATH; AMPLIFICATION; AFTERSHOCKS; WAVE AB On average, soil sites behaved nonlinearly during the M 6.7 1994 Northridge, California, earthquake. This conclusion follows from an analysis that combines elements of two independent lines of investigation. First, we apply the stochastic finite-fault simulation method, calibrated with 28 rock-site recordings of the Northridge mainshock, to the simulation of the input motions to the soil sites that recorded this event. The calibrated model has a near-zero average bias in reproducing ground motions at rock sites in the frequency range from 0.1 to 12.5 Hz. The soil sites selected are those where there is colocation of strong-motion accelerographs and temporary instruments from the Northridge aftershock observation network. At these sites, weak-motion amplification functions based on numerous aftershock records have been empirically determined, in three separate investigations reported in the literature. These empirical weak-motion amplification factors can be applied to the simulated input rock motions, at each soil site, to determine the expected motions during the mainshock (i.e., neglecting nonlinearity). These expected motions can then be compared to the actual recordings during the mainshock. This analysis shows that the recorded strong-motion spectra are significantly overestimated if weak-motion amplifications are used. The null hypothesis, stating that the inferred differences between weak- and strong-motion amplifications are statistically insignificant, is rejected with 95% confidence in the frequency range from approximately 2.2 to 10 Hz. On average, the difference between weak- and strong-motion amplifications is a factor of 2. Nonlinear response at those soil stations for which the input peak acceleration exceeded 150 to 200 cm/sec(2) contributes most to this observed average difference. These findings suggest a significant nonlinear response at soil stations in the Los Angeles urban area during the Northridge mainshock. The effect is consistent with the increase in damping of shear waves at high levels of strain, which is well known from geotechnical studies of soil properties. C1 Iowa State Univ, Dept Geol & Atmospher Sci, Ames, IA 50011 USA. Carleton Univ, Dept Earth Sci, Ottawa, ON K1S 5B6, Canada. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ So Calif, Dept Earth Sci, Los Angeles, CA 90089 USA. RP Beresnev, IA (reprint author), Iowa State Univ, Dept Geol & Atmospher Sci, 253 Sci I, Ames, IA 50011 USA. EM beresnev@iastate.edu; gma@ccs.carleton.ca; johnson@seismo5.lanl.gov; field@usc.edu NR 25 TC 34 Z9 34 U1 0 U2 3 PU SEISMOLOGICAL SOC AMER PI EL CERRITO PA PLAZA PROFESSIONAL BLDG, SUITE 201, EL CERRITO, CA 94530 USA SN 0037-1106 J9 B SEISMOL SOC AM JI Bull. Seismol. Soc. Amer. PD DEC PY 1998 VL 88 IS 6 BP 1402 EP 1410 PG 9 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 154XA UT WOS:000077914300007 ER PT J AU Guthrie, GD Reynolds, RC AF Guthrie, GD Reynolds, RC TI A coherent TEM- and XRD-description of mixed-layer illite/smectite SO CANADIAN MINERALOGIST LA English DT Article DE illite; smectite; X-ray diffraction; transmission electron microscopy; mixed-layer I/S ID ILLITE-SMECTITE; INTERSTRATIFIED CLAYS; DIFFRACTION; PARTICLES; SILICATES AB We present a model for the low-charge (smectite?) layers in mixed-layer illite/smectite based on an integration of observations from transmission electron microscopy (TEM) and powder X-ray diffraction (XRD). This model is an attempt to account for the apparent discrepancies in the structural descriptions based solely on one technique or the other, in which the low-charge interlayers appear to be coherent interfaces by TEM but incoherent interfaces by XRD. In our model, the low-charge boundaries between adjacent 2:1 layers are semicoherent owing to rotational disorder (i.e., they are turbostratically stacked), but the degree of rotational disorder is limited. Such a model is consistent with both TEM and XRD observations and with an intuitive model of the interlayer-site occupancy: if a low-charge interlayer must have approximately 1/4 to 1/3 of the total sites occupied to satisfy charge balance, then the rotational disorder must be less than similar to 10-15 degrees. C1 Western Michigan Univ, Dept Geol, Kalamazoo, MI 49008 USA. Los Alamos Natl Lab, Geol & Geochem Grp, Los Alamos, NM 87545 USA. Dartmouth Coll, Dept Earth Sci, Hanover, NH 03755 USA. RP Guthrie, GD (reprint author), Western Michigan Univ, Dept Geol, Kalamazoo, MI 49008 USA. EM gguthrie@lanl.gov; robert.c.reynolds@dartmouth.edu NR 31 TC 12 Z9 12 U1 1 U2 5 PU MINERALOGICAL ASSOC CANADA PI OTTAWA PA PO BOX 78087, MERILINE POSTAL OUTLET, 1460 MERIVALE RD, OTTAWA, ONTARIO K2E 1B1, CANADA SN 0008-4476 J9 CAN MINERAL JI Can. Mineral. PD DEC PY 1998 VL 36 BP 1421 EP 1434 PN 6 PG 14 WC Mineralogy SC Mineralogy GA 189JG UT WOS:000079900900005 ER PT J AU White, RB Benkadda, S Kassibrakis, S Zaslavsky, GM AF White, RB Benkadda, S Kassibrakis, S Zaslavsky, GM TI Near threshold anomalous transport in the standard map SO CHAOS LA English DT Article ID AREA-PRESERVING MAPS; SELF-SIMILARITY; LEVY FLIGHTS; RANDOM-WALKS; DIFFUSION; CHAOS; TRANSITION; MODEL; FLOW AB Anomalous transport is investigated near threshold in the standard map. Very long time flights, and a large anomaly in the transport, are shown to be associated with a new form of multi-island structures causing orbit sticking. The phase space structure of these traps, and the exponents of the characteristic long time tails associated with them are determined. In general these structures are very complex, but some cases, consisting of layers of islands, allow simple modeling. (C) 1998 American Institute of Physics. [S1054-1500(98)01403-7]. C1 Princeton Univ, Plasma Phys Lab, Princeton, NJ 08543 USA. Univ Aix Marseille 1, CNRS, UMR 6633, F-13397 Marseille 20, France. NYU, Courant Inst Math Sci, New York, NY 10012 USA. NYU, Dept Phys, New York, NY 10003 USA. RP Princeton Univ, Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. RI White, Roscoe/D-1773-2013 OI White, Roscoe/0000-0002-4239-2685 NR 34 TC 29 Z9 29 U1 0 U2 3 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 1054-1500 EI 1089-7682 J9 CHAOS JI Chaos PD DEC PY 1998 VL 8 IS 4 BP 757 EP 767 DI 10.1063/1.166361 PG 11 WC Mathematics, Applied; Physics, Mathematical SC Mathematics; Physics GA 146TJ UT WOS:000077446700003 ER PT J AU Carley, JF AF Carley, JF TI The marrying kind SO CHEMICAL ENGINEERING PROGRESS LA English DT Letter C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Carley, JF (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER INST CHEMICAL ENGINEERS PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0360-7275 J9 CHEM ENG PROG JI Chem. Eng. Prog. PD DEC PY 1998 VL 94 IS 12 BP 6 EP 6 PG 1 WC Engineering, Chemical SC Engineering GA 147FG UT WOS:000077477500004 ER PT J AU Hamada, T Sakaki, S Brunschwig, BS Fujita, E Wishart, JF AF Hamada, T Sakaki, S Brunschwig, BS Fujita, E Wishart, JF TI High enantioselectivity in the electron transfer reaction between a Ru(II) complex of menbpy anion radical, [Ru(menbpy)(3)](+) [menbpy = 4,4 '-di{(1R,2S,5R)-(-)-menthoxycarbonyl}-2,2 '-bipyridine] and [Co(acac)(3)]: A pulse radiolysis study SO CHEMISTRY LETTERS LA English DT Article ID HELICAL RUTHENIUM(II) COMPLEXES; METAL REDOX COUPLES; ENTHALPIC CONTRIBUTIONS; SOLVENT DEPENDENCE; REDUCTION; STEREOSELECTIVITY; PHOTOSENSITIZER; PHOTOCATALYSIS; THERMODYNAMICS; COBALT(III) AB One-electron reduction of [Ru(menbpy)(3)](2+) [menbpy = 4,4'- di{(1R,2S,SR)- (-)- menthoxycarbonyl}-2,2'-bipyridine] by pulse radiolysis produces a Ru(II) complex of a menbpy-centered anion radical, which reduces Delta-[Co(acac)(3)] more rapidly than Lambda-[Co(acac)(3)] with an enantioselectivity of 2.7 in 85% EtOH/H2O. C1 Kumamoto Univ, Fac Engn, Dept Appl Chem & Biochem, Kumamoto 8608555, Japan. Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. RP Sakaki, S (reprint author), Kumamoto Univ, Fac Engn, Dept Appl Chem & Biochem, Kumamoto 8608555, Japan. RI Brunschwig, Bruce/G-4249-2011; Fujita, Etsuko/D-8814-2013; Wishart, James/L-6303-2013 OI Wishart, James/0000-0002-0488-7636 NR 21 TC 5 Z9 5 U1 2 U2 8 PU CHEMICAL SOC JAPAN PI TOKYO PA 1-5 KANDA-SURUGADAI CHIYODA-KU, TOKYO, 101-8307, JAPAN SN 0366-7022 EI 1348-0715 J9 CHEM LETT JI Chem. Lett. PD DEC PY 1998 IS 12 BP 1259 EP 1260 DI 10.1246/cl.1998.1259 PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA 151VD UT WOS:000077740600035 ER PT J AU Yang, LH Consorte, CD Fong, CY Pask, JE Nabighian, E Kauzlarich, SM Nelson, JS AF Yang, LH Consorte, CD Fong, CY Pask, JE Nabighian, E Kauzlarich, SM Nelson, JS TI Theoretical study of electronic properties of Zintl phase KSi SO CHEMISTRY OF MATERIALS LA English DT Article ID MAIN-GROUP ELEMENTS; POROUS SILICON; COMPOUND; SYSTEMS AB We have studied the electronic properties of Zintl phase KSi, by the ab initio density functional pseudopotential method. Our interest in this Zintl compound is in its current use as a reagent in the synthesis of Si nanoclusters. The structure consists of isolated Sir tetrahedra with K atoms situated above each face. The crystal system is cubic with the symmetry of the P (4) over bar 3m space group. Band structure calculations show a band gap of 1.3 eV. The presence of K atoms has widened the band gap over that found between occupied and unoccupied energy levels in the Si-4 cluster. The valence bandwidth lies between the valence bandwidth of crystalline Si with diamond structure and the width of the occupied energy levels of the Si-4 cluster. The density of states shows four major structures for the occupied bands. The lowest energy band of conduction states is also given in the density of states plot. The nature of the bonding in the crystal is revealed by an examination of the charge density associated with each of the structures in the density of states. It is found that the dominant bonding between Si atoms is not the covalent bonding of sp(3) hybridized orbitals, as found in diamond structure Si-4 but is rather a mutual overlap of s- and p-like mixed atomic states from each Si atom. These overlapped states form a bonding state located at the center of the tetrahedron. Furthermore, each K atom is ionized by the nearest Si-4 tetrahedra, allowing the Si atom to fill its 3s and 3p shells. C1 Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. Sandia Natl Labs, Semiconductor Mat & Device Sci Dept, Albuquerque, NM 87185 USA. Univ Calif Davis, Dept Chem, Davis, CA 95616 USA. Lawrence Livermore Natl Lab, Div H, Livermore, CA 94551 USA. RP Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. NR 35 TC 1 Z9 1 U1 1 U2 5 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0897-4756 EI 1520-5002 J9 CHEM MATER JI Chem. Mat. PD DEC PY 1998 VL 10 IS 12 BP 4025 EP 4029 DI 10.1021/cm9804564 PG 5 WC Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 151QX UT WOS:000077733100036 ER PT J AU Sasaki, T Kooli, F Iida, M Michiue, Y Takenouchi, S Yajima, Y Izumi, F Chakoumakos, BC Watanabe, M AF Sasaki, T Kooli, F Iida, M Michiue, Y Takenouchi, S Yajima, Y Izumi, F Chakoumakos, BC Watanabe, M TI A mixed alkali metal titanate with the lepidocrocite-like layered structure. Preparation, crystal structure, protonic form, and acid-base intercalation properties SO CHEMISTRY OF MATERIALS LA English DT Article ID VISIBLE-LIGHT PHOTOLYSIS; HYDROUS TITANIUM-DIOXIDE; ION-EXCHANGE; SEMICONDUCTOR PARTICLES; K4NB6O17; TIO2(B) AB A mixed alkali metal titanate of composition A(x)Ti(2-x/3)Li(x/3c)O(4) (A = K, Rb, Cs) has been prepared and its ion-exchange/intercalation properties have been explored. Solid-state calcination of appropriate mixtures of TiO2 and alkali metal carbonates produced the titanate at a stoichiometry of x = 0.80 for A = K, 0.75 for Rb, and 0.70 for Cs. Rietveld refinement on neutron diffraction data confirmed that the orthorhombic structure is comprised of lepidocrocite-related host layers of Ti2-x/3Lix/3O4 and charge-balancing A ions in the interlayer domain. Complete extraction of both alkali metal ions was achieved by acid-leaching, producing a new protonic titanate of H4x/3Ti2-x/3O4. H2O. This phase is distinguished from isomorphous related compounds in terms of high proton content as a consequence of exchangeable Li ions located in the host framework. The material took up alkali metal ions and organoammonium ions from aqueous media. These ion-exchange and intercalation reactions brought about expansion/contraction of the gallery height and lateral displacement of the layers. The resulting various types of layer sequence can be understood in terms of the nature of the interlayer species. C1 Natl Inst Res Inorgan Mat, Tsukuba, Ibaraki 3050044, Japan. Ishihara Sangyo Kaisha, Yokkaichi, Mie 5940084, Japan. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Sasaki, T (reprint author), Natl Inst Res Inorgan Mat, 1-1 Namiki, Tsukuba, Ibaraki 3050044, Japan. RI Chakoumakos, Bryan/A-5601-2016 OI Chakoumakos, Bryan/0000-0002-7870-6543 NR 37 TC 110 Z9 111 U1 9 U2 71 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0897-4756 J9 CHEM MATER JI Chem. Mat. PD DEC PY 1998 VL 10 IS 12 BP 4123 EP 4128 DI 10.1021/cm980535f PG 6 WC Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 151QX UT WOS:000077733100048 ER PT J AU Loy, DA Carpenter, JP Yamanaka, SA McClain, MD Greaves, J Hobson, S Shea, KJ AF Loy, DA Carpenter, JP Yamanaka, SA McClain, MD Greaves, J Hobson, S Shea, KJ TI Polymerization of bis(triethoxysilyl) ethenes. Impact of substitution geometry on the formation of ethenylene- and vinylidene-bridged polysilsesquioxanes SO CHEMISTRY OF MATERIALS LA English DT Article ID SI-29 NMR; SILICON; CONDENSATION; GELS; ACID AB In this study, we utilized the substitution geometry of triethoxysilyl groups about an organic bridging group to control the outcome of the sol-gel polymerization process. The substitution geometry of two triethoxysilyl groups about a carbon-carbon double bond was determined to have a profound effect on sol-gel polymerizations of the E (1) and Z (2) ethenylene-bridged monomers and vinylidene-bridged monomer (3) and on the porosity in the resulting xerogels. Si-29 NMR and chemical ionization mass spectrometry were used to elucidate the early sol-gel chemistry in the acid-catalyzed polymerizations of 1-3. Trans substitution about the ethenylene-bridging group in 1 led to acyclic and monocyclic dimers and trimers as condensation products under acidic conditions and only microporous gels under both acidic and basic conditions. In contrast, cyclization reactions dominated the sol-gel chemistry of 2 beginning with intramolecular cyclization to give the cyclic disilses-quioxane (4) and continued with the formation of cyclic oligomers, including a bicyclic dimer. The cyclization of 2 slowed the rate of gelation compared to 1 and afforded microporous xerogels under acidic conditions and mesoporous gels under basic conditions. The sol-gel chemistry of the vinylidene monomer (3) was strongly retarded by the formation of a cyclic dimer (5). Only mesoporous gels were formed under basic conditions after 9 months; no gels were obtained under acidic conditions. C1 Sandia Natl Labs, Dept Encapsulants & Foams, Albuquerque, NM 87185 USA. Univ Calif Irvine, Dept Chem, Irvine, CA 92717 USA. RP Loy, DA (reprint author), Sandia Natl Labs, Dept Encapsulants & Foams, POB 5800, Albuquerque, NM 87185 USA. RI Loy, Douglas/D-4847-2009 OI Loy, Douglas/0000-0001-7635-9958 NR 20 TC 22 Z9 23 U1 1 U2 12 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0897-4756 J9 CHEM MATER JI Chem. Mat. PD DEC PY 1998 VL 10 IS 12 BP 4129 EP 4140 DI 10.1021/cm9805424 PG 12 WC Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 151QX UT WOS:000077733100049 ER PT J AU Subramaniam, S Pope, SB AF Subramaniam, S Pope, SB TI A mixing model for turbulent reactive flows based on Euclidean minimum spanning trees SO COMBUSTION AND FLAME LA English DT Article ID PASSIVE SCALARS; GRADIENT AB In modeling turbulent reactive flows based on the transport equation for the joint probability density function (jpdf) of velocity and composition, the change in fluid composition due to convection and reaction is treated exactly, while molecular mixing has to be modeled. A new mixing model is proposed, which is local in composition space and which seeks to address problems encountered in flows with simultaneous mixing and reaction. In this model the change in particle composition is determined by particle interactions along the edges of a Euclidean minimum spanning tree (EMST) constructed in composition space. Results obtained for the model problem of passive scalars evolving under the influence of a mean scalar gradient in homogeneous turbulence are found to be in reasonable agreement with experimental findings of Sirivat and Warhaft (1983). The model is applied to the diffusion flame test model problem proposed by Norris and Pope (1991) and its performance is found to be superior to that of existing models. The essential feature of the new EMST mixing model, which accounts for its success in the diffusion flame test, is that mixing is modeled locally in composition space. (C) 1998 by The Combustion Institute. C1 Cornell Univ, Sibley Sch Mech & Aerosp Engn, Ithaca, NY 14853 USA. RP Subramaniam, S (reprint author), Los Alamos Natl Lab, T-3,MS B216, Los Alamos, NM 87545 USA. RI Pope, Stephen/F-6268-2011 OI Pope, Stephen/0000-0001-5629-0420 NR 26 TC 185 Z9 190 U1 1 U2 10 PU ELSEVIER SCIENCE INC PI NEW YORK PA 360 PARK AVE SOUTH, NEW YORK, NY 10010-1710 USA SN 0010-2180 J9 COMBUST FLAME JI Combust. Flame PD DEC PY 1998 VL 115 IS 4 BP 487 EP 514 DI 10.1016/S0010-2180(98)00023-6 PG 28 WC Thermodynamics; Energy & Fuels; Engineering, Multidisciplinary; Engineering, Chemical; Engineering, Mechanical SC Thermodynamics; Energy & Fuels; Engineering GA 103QU UT WOS:000074970000005 ER PT J AU Marsden, JE Patrick, GW Shkoller, S AF Marsden, JE Patrick, GW Shkoller, S TI Multisymplectic geometry, variational integrators, and nonlinear PDEs SO COMMUNICATIONS IN MATHEMATICAL PHYSICS LA English DT Article ID KLEIN-GORDON EQUATION; NUMERICAL-SOLUTION; ALGORITHMS; SYSTEMS AB This paper presents a geometric-variational approach to continuous and discrete mechanics and field theories. Using multisymplectic geometry, we show that the existence of the fundamental geometric structures as well as their preservation along solutions can be obtained directly from the variational principle. In particular, we prove that a unique multisymplectic structure is obtained by taking the derivative of an action function, and use this structure to prove covariant generalizations of conservation of symplecticity and Noether's theorem. Natural discretization schemes for PDEs, which have these important preservation properties, then follow by choosing a discrete action functional. In the case of mechanics, we recover the variational symplectic integrators of Veselov type, while for PDEs we obtain covariant spacetime integrators which conserve the corresponding discrete multisymplectic form as well as the discrete momentum mappings corresponding to symmetries. We show that the usual notion of symplecticity along an infinite-dimensional space of fields can be naturally obtained by making a spacetime split. All of the aspects of our method are demonstrated with a nonlinear sine-Gordon equation, including computational results and a comparison with other discretization schemes. C1 CALTECH, Pasadena, CA 91125 USA. Univ Saskatchewan, Dept Math & Stat, Saskatoon, SK S7N 5E6, Canada. Los Alamos Natl Lab, Ctr Nonlinear Studies, Los Alamos, NM 87545 USA. RP Marsden, JE (reprint author), CALTECH, 107-81, Pasadena, CA 91125 USA. EM marsden@cds.caltech.edu; patrick@math.usask.ca; shkoller@cds.caltech.edu NR 36 TC 274 Z9 293 U1 1 U2 15 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0010-3616 EI 1432-0916 J9 COMMUN MATH PHYS JI Commun. Math. Phys. PD DEC PY 1998 VL 199 IS 2 BP 351 EP 395 DI 10.1007/s002200050505 PG 45 WC Physics, Mathematical SC Physics GA 154RH UT WOS:000077902200006 ER PT J AU Gray, LJ Griffith, BE AF Gray, LJ Griffith, BE TI A faster Galerkin boundary integral algorithm SO COMMUNICATIONS IN NUMERICAL METHODS IN ENGINEERING LA English DT Article ID HYPERSINGULAR INTEGRALS; CURVED ELEMENTS; FORMULATION; ELASTICITY; EQUATIONS; CRACK AB The symmetry present in Green's functions is exploited to significantly reduce the matrix assembly time for a Galerkin boundary integral analysis. A relatively simple modification of the standard Galerkin implementation for computing the non-singular integrals yields a 20-30 per cent decrease in computation time. This faster Galerkin method is developed for both singular and hypersingular equations, and applied to symmetric-Galerkin implementations in two dimensions for the Laplace equation and for orthotropic elasticity. In three dimensions, the modified algorithm has been implemented for the singular equation for the Laplace and elastodynamics equations. Comparison timing results for standard and modified algorithms are presented. (C) 1998 John Wiley & Sons, Ltd. C1 Oak Ridge Natl Lab, Div Math & Comp Sci, Oak Ridge, TN 37831 USA. Rice Univ, Dept Computat & Appl Math, Houston, TX 77005 USA. RP Gray, LJ (reprint author), Oak Ridge Natl Lab, Div Math & Comp Sci, Oak Ridge, TN 37831 USA. NR 27 TC 9 Z9 9 U1 0 U2 0 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 1069-8299 J9 COMMUN NUMER METH EN JI Commun. Numer. Methods Eng. PD DEC PY 1998 VL 14 IS 12 BP 1109 EP 1117 DI 10.1002/(SICI)1099-0887(199812)14:12<1109::AID-CNM211>3.0.CO;2-H PG 9 WC Engineering, Multidisciplinary; Mathematics, Interdisciplinary Applications SC Engineering; Mathematics GA 154LG UT WOS:000077890200002 ER PT J AU Rowe, CL AF Rowe, CL TI Elevated standard metabolic rate in a freshwater shrimp (Palaemonetes paludosus) exposed to trace element-rich coal combustion waste SO COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY A-MOLECULAR AND INTEGRATIVE PHYSIOLOGY LA English DT Article DE coal ash; heavy metals; maintenance energetics; oxygen consumption; sublethal effects ID OXYGEN-CONSUMPTION; ASH; ECOTOXICOLOGY; RESPONSES; MOLLUSKS; STRESS; METALS AB I conducted a transplant experiment to determine whether standard metabolic rate (SMR) of a freshwater shrimp (Palaemonetes paludosus) would be affected by exposure to tract element-enriched coal combustion waste ('coal ash'). Shrimp were transplanted into replicate cages in a coal ash-polluted site and a reference site for 8 months. The coal ash-polluted site was characterized by elevated sediment concentrations of As, Cd, Cr, Cu, Ni, Pb, and Se compared to sediments in the reference site. After 8 months in the study sites, shrimp in the polluted site appeared to have accumulated As, Cd. and Se from the habitat, but there were no differences in survival between the study sites. However, mean SMR of shrimp (measured as O-2 consumption at rest) held in the polluted site was 51% higher than mean SMR of shrimp held in the reference site. The elevation ill SMR indicates that the energetic costs of maintenance are greater for shrimp chronically exposed to the coal-ash, polluted environment than shrimp in the reference site. It is likely, therefore, that other physiological or behavioral processes may be modified in the pollution-exposed individuals to compensate for the increased energy demands for maintenance. Recent studies have reported similar elevations in SMR in an amphibian and a reptile chronically exposed to coal ash. Analogous physiological responses in such taxonomically diverse animals (a crustacean, an amphibian, and a reptile) indicate that elevated SMR may be a general response by many types of organisms exposed to the mixture of trace elements characteristic of coal ash. The relationships among pollution-induced elevations in maintenance expenditures, long-term health of individuals, and population-level parameters require further attention. (C) 1998 Elsevier Science Inc. All rights reserved. C1 Univ Georgia, Savannah River Ecol Lab, Aiken, SC 29802 USA. RP Rowe, CL (reprint author), Univ Puerto Rico, Dept Biol, POB 23360, Rio Piedras, PR 00931 USA. RI Rowe, Christopher/D-5271-2012 NR 36 TC 28 Z9 29 U1 4 U2 15 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 1095-6433 J9 COMP BIOCHEM PHYS A JI Comp. Biochem. Physiol. A-Mol. Integr. Physiol. PD DEC PY 1998 VL 121 IS 4 BP 299 EP 304 DI 10.1016/S1095-6433(98)10141-1 PG 6 WC Biochemistry & Molecular Biology; Physiology; Zoology SC Biochemistry & Molecular Biology; Physiology; Zoology GA 151RC UT WOS:000077733600001 ER PT J AU Wright, SJ AF Wright, SJ TI Superlinear convergence of a stabilized SQP method to a degenerate solution SO COMPUTATIONAL OPTIMIZATION AND APPLICATIONS LA English DT Article DE nonlinear programming; sequential quadratic programming; degenerate solutions AB We describe a slight modification of the well-known sequential quadratic programming method for nonlinear programming that attains superlinear convergence to a primal-dual solution even when the Jacobian of the active constraints is rank deficient at the solution. We show that rapid convergence occurs even in the presence of the roundoff errors that are introduced when the algorithm is implemented in floating-point arithmetic. C1 Argonne Natl Lab, Div Math & Comp Sci, Argonne, IL 60439 USA. RP Wright, SJ (reprint author), Argonne Natl Lab, Div Math & Comp Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 13 TC 73 Z9 76 U1 0 U2 2 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0926-6003 J9 COMPUT OPTIM APPL JI Comput. Optim. Appl. PD DEC PY 1998 VL 11 IS 3 BP 253 EP 275 DI 10.1023/A:1018665102534 PG 23 WC Operations Research & Management Science; Mathematics, Applied SC Operations Research & Management Science; Mathematics GA 138PA UT WOS:000076980400002 ER PT J AU Katkov, II Katkova, N Critser, JK Mazur, P AF Katkov, II Katkova, N Critser, JK Mazur, P TI Mouse spermatozoa in high concentrations of glycerol: Chemical toxicity vs osmotic shock at normal and reduced oxygen concentrations SO CRYOBIOLOGY LA English DT Article ID SPONTANEOUS LIPID-PEROXIDATION; SPINACH CHLOROPLAST MEMBRANES; CRYOPRESERVED SPERMATOZOA; SUPEROXIDE-DISMUTASE; HYDROGEN-PEROXIDE; COOLING RATE; WARMING RATE; HUMAN SPERM; SURVIVAL; EMBRYOS AB The cryobiological preservation of mouse spermatozoa has presented difficulties in the form of poor motilities or irreproducibility. We have identified several likely underlying problems. One is that published studies have used concentrations of the cryoprotectant glycerol that are substantially lower (0.3 M) than the similar to 1 M concentrations that are optimal for most cells. Another may arise from the known high susceptibility of mouse sperm to free radical damage. We have identified two contributors to damage from higher concentrations of glycerol, namely, chemical toxicity proportional to concentration and exposure time and osmotic damage arising from too rapid an addition and removal of the glycerol. When toxicity is minimized by restricting the exposure time to 1 or 5 min and osmotic shock is minimized by adding and removing the glycerol stepwise, relatively high percentages of the sperm survive contact with 0.8 M glycerol. Free-radical damage in mouse sperm is known to be proportional to the oxygen concentration. We have determined the consequences of reducing the oxygen to <3% of atmospheric by the use of a bacterial membrane preparation, Oxyrase. Oxyrase reduced damage from centrifugation and substantially reduced damage from osmotic shock; however, it did not significantly reduce glycerol toxicity. (C) 1998 Academic Press. C1 Oak Ridge Natl Lab, Div Life Sci, Oak Ridge, TN USA. Oak Ridge Associated Univ, Oak Ridge, TN USA. Indiana Univ, Sch Med, Cryobiol Res Inst, Indianapolis, IN USA. Univ Tennessee, Dept Biochem & Cellular & Mol Biol, Knoxville, TN 37996 USA. RP Katkov, II (reprint author), Universal Preservat Technol Inc, 11045 Roselle St,Suite C, San Diego, CA 92121 USA. RI Katkov, Igor/D-7163-2015 OI Katkov, Igor/0000-0001-9251-0494 FU NICHD NIH HHS [R01-HD30274] NR 46 TC 62 Z9 63 U1 1 U2 6 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0011-2240 J9 CRYOBIOLOGY JI Cryobiology PD DEC PY 1998 VL 37 IS 4 BP 325 EP 338 DI 10.1006/cryo.1998.2128 PG 14 WC Biology; Physiology SC Life Sciences & Biomedicine - Other Topics; Physiology GA 164LA UT WOS:000078464400006 PM 9917349 ER PT J AU Sumption, MD Scanlan, RM Collings, EW AF Sumption, MD Scanlan, RM Collings, EW TI AC loss properties of some Bi : 2212/Ag Rutherford cables and a comparison with those of cables wound with NbTi and Nb3Sn SO CRYOGENICS LA English DT Article DE Rutherford cable; cores; NbTi; Nb3Sn; Bi : 2212/Ag; AC loss; contact resistance ID INTERNAL-TIN; COUPLING LOSSES; SUPERCONDUCTORS; RESISTANCE; CONDUCTORS; CURRENTS; STRANDS; FIELDS AB Calorimetric measurements of AC loss have been performed on Rutherford cables wound with NbTi, Nb3Sn, and Bi:2212/Ag strands, respectively. For the NbTi cables, various strand coatings had been applied, while for the Nb,Sn and Bi:2212/Ag cables the strand surfaces were just bare Cu or Ag, respectively. Most of the cables contained resistive cores: ribbons of kapton or titanium (NbTi cables), stainless steel (NbTi and Nb3Sn cables), and nichrome-80 (Bi:2212/Ag cables). In all cases the cores were found to lead to a strong suppression of the face-on (field normal to the broad cable face) coupling current loss; to such an extent that even the Bi:2212/Ag cables, which would otherwise be severely cross-sintered, evinced acceptable coupling loss. For most of the cables side-by-side interstrand contact resistances have been calculated. An 'effective interstrand contact resistance', R-perpendicular to,(eff), has been defined, and an expression devised to enable its value in different-size cables to be converted to that of a 'standard reference cable', R-perpendicular to,(effx.,ref.), for the purpose of intercomparison. (C) 1999 Elsevier Science Ltd. All rights reserved. C1 Ohio State Univ, Dept Mat Sci & Engn, Columbus, OH 43210 USA. Lawrence Berkeley Natl Lab, Superconducting Magnet Grp, Berkeley, CA 94720 USA. RP Sumption, MD (reprint author), Ohio State Univ, Dept Mat Sci & Engn, Columbus, OH 43210 USA. RI Sumption, Mike/N-5913-2016 OI Sumption, Mike/0000-0002-4243-8380 NR 25 TC 7 Z9 7 U1 1 U2 4 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0011-2275 J9 CRYOGENICS JI Cryogenics PD DEC PY 1998 VL 38 IS 12 BP 1225 EP 1232 DI 10.1016/S0011-2275(98)00116-7 PG 8 WC Thermodynamics; Physics, Applied SC Thermodynamics; Physics GA 173PW UT WOS:000078989800006 ER PT J AU Raikhel, NV Clarke, AE AF Raikhel, NV Clarke, AE TI Plant cell biology: an all-inclusive field SO CURRENT OPINION IN PLANT BIOLOGY LA English DT Editorial Material C1 Michigan State Univ, MSU DOE Plant Res Lab, E Lansing, MI 48824 USA. Univ Melbourne, Sch Bot, Plant Cell Biol Res Ctr, Parkville, Vic 3052, Australia. RP Raikhel, NV (reprint author), Michigan State Univ, MSU DOE Plant Res Lab, E Lansing, MI 48824 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU CURRENT BIOLOGY LTD PI LONDON PA 34-42 CLEVELAND STREET, LONDON W1P 6LE, ENGLAND SN 1369-5266 J9 CURR OPIN PLANT BIOL JI Curr. Opin. Plant Biol. PD DEC PY 1998 VL 1 IS 6 BP 455 EP 457 DI 10.1016/S1369-5266(98)80034-4 PG 3 WC Plant Sciences SC Plant Sciences GA 146CM UT WOS:000077410300001 ER PT J AU Downing, KH Nogales, E AF Downing, KH Nogales, E TI Tubulin structure: insights into microtubule properties and functions SO CURRENT OPINION IN STRUCTURAL BIOLOGY LA English DT Article ID DIVISION PROTEIN FTSZ; FUNCTION IN-VIVO; BETA-TUBULIN; COLCHICINE-BINDING; GTP HYDROLYSIS; ALPHA-TUBULIN; AMINO-ACIDS; PHOTOLABELS; DYNAMICS; ISOTYPES AB The structure of tubulin has recently been determined by electron crystallography, paving the way for a clearer understanding of the unique properties of tubulin that allow its varied functions within the cell. Some of the ongoing work on tubulin can be interpreted in terms of its structure, which can serve to guide future studies. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Donner Lab, Div Life Sci, Berkeley, CA 94720 USA. RP Downing, KH (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Donner Lab, Div Life Sci, Berkeley, CA 94720 USA. NR 50 TC 113 Z9 115 U1 2 U2 10 PU CURRENT BIOLOGY LTD PI LONDON PA 34-42 CLEVELAND STREET, LONDON W1P 6LE, ENGLAND SN 0959-440X J9 CURR OPIN STRUC BIOL JI Curr. Opin. Struct. Biol. PD DEC PY 1998 VL 8 IS 6 BP 785 EP 791 DI 10.1016/S0959-440X(98)80099-7 PG 7 WC Biochemistry & Molecular Biology; Cell Biology SC Biochemistry & Molecular Biology; Cell Biology GA 149PN UT WOS:000077614300016 PM 9914260 ER PT J AU Sun, X Lee, HS Lee, S Yang, XQ McBreen, J AF Sun, X Lee, HS Lee, S Yang, XQ McBreen, J TI A novel lithium battery electrolyte based on lithium fluoride and a tris(pentafluorophenyl) borane anion receptor in DME SO ELECTROCHEMICAL AND SOLID STATE LETTERS LA English DT Article ID ION-PAIR DISSOCIATION; NONAQUEOUS SOLUTIONS; CONDUCTIVITY; SALTS; FAMILY AB For the first time, lithium fluoride has been successfully used as a salt in a novel, highly conductive, nonaqueous electrolyte in a rechargeable Li/LiMn2 O-4 cell. This was accomplished by using LiF with a new boron-based anion receptor additive in a 1,2-dimethoxyethane (DME) solvent. The additive increases the solubility of LiF in DME to as high as 1 M and results in a conductivity of 6.8 x 10(-3) S/ cm at 25 degrees C. On a glassy carbon working electrode, the electrolyte was electrochemically stable up to 4.46 V. The upper voltage limit is due to the solvent and not the additive. The feasibility of using the electrolyte in a rechargeable lithium battery was studied. A test cell with a LiMn2O4 cathode and the new electrolyte was cycled 51 times between 3.5 and 4.3 V. The initial capacity was almost identical to that found in a cell with a commercial electrolyte [1 M LiPF6 in propylene carbonate/ethylene carbonate/dimethyl carbonate (1: 1: 3)]. With the new electrolyte, there was some capacity fade and an increase in cell polarization with cycling due to decomposition of the solvent. New, more stable solvents with similar solubilities for the additive are needed. (C) 1998 The Electrochemical Society. S1099- 0062(98) 06-016-7. All rights reserved. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. RP Sun, X (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. EM xyang@bnl.gov NR 12 TC 47 Z9 47 U1 3 U2 34 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 65 SOUTH MAIN STREET, PENNINGTON, NJ 08534 USA SN 1099-0062 J9 ELECTROCHEM SOLID ST JI Electrochem. Solid State Lett. PD DEC PY 1998 VL 1 IS 6 BP 239 EP 240 PG 2 WC Electrochemistry; Materials Science, Multidisciplinary SC Electrochemistry; Materials Science GA 185XN UT WOS:000079696400001 ER PT J AU Ren, F LaRoche, J Anderson, T Pearton, SJ Lee, JW Johnson, D Lothian, JR Lin, J Weiner, JS Shul, RJ Wu, CS AF Ren, F LaRoche, J Anderson, T Pearton, SJ Lee, JW Johnson, D Lothian, JR Lin, J Weiner, JS Shul, RJ Wu, CS TI Electron cyclotron resonance chemical vapor deposited silicon nitride for T-gate passivation SO ELECTROCHEMICAL AND SOLID STATE LETTERS LA English DT Article ID PSEUDOMORPHIC HEMTS; PLASMA AB SiNx deposited by electron cyclotron resonance chemical vapor deposition (ECRCVD) was successfully employed for 0.25 mu m T-gate passivation. The SiNx film showed excellent step coverage, and the device was passivated with an 800 Angstrom SiNx film, which minimized the increase of extrinsic gate capacitance due to the additional dielectric layer covering the intrinsic device. The SiNx deposition temperature was kept at 50 degrees C (compatible with conventional lithography processes) and a pattern of 1500 Angstrom SiNx was lifted off with AZ 5209 resist. Due to the higher efficiency of ion generation for the ECRCVD system, a dilute silane/nitrogen mixture was used to deposit the SiNx instead of silane/ammonia. From atomic force microscopy data, the deposited SiNx also planarized the deposition surface. The root mean square roughness of a 4 in. silicon wafer was reduced from 6.29 to 2.50 Angstrom after a 2000 Angstrom SiNx deposition. (C) 1998 The Electrochemical Society. S1099-0062(98)04-074-7. All rights reserved. C1 Univ Florida, Gainesville, FL 32611 USA. Plasma Therm Inc, St Petersburg, FL 33716 USA. AT&T Bell Labs, Lucent Technol, Murray Hill, NJ 07974 USA. Sandia Natl Labs, Albuquerque, NM 87123 USA. TRW Co Inc, Redondo Beach, CA 90278 USA. RP Ren, F (reprint author), Univ Florida, Gainesville, FL 32611 USA. NR 11 TC 1 Z9 1 U1 0 U2 0 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 65 SOUTH MAIN STREET, PENNINGTON, NJ 08534 USA SN 1099-0062 J9 ELECTROCHEM SOLID ST JI Electrochem. Solid State Lett. PD DEC PY 1998 VL 1 IS 6 BP 279 EP 281 PG 3 WC Electrochemistry; Materials Science, Multidisciplinary SC Electrochemistry; Materials Science GA 185XN UT WOS:000079696400015 ER PT J AU Boyd, BM Prausnitz, JM Blanch, HW AF Boyd, BM Prausnitz, JM Blanch, HW TI High-frequency alternating-crossed-field gel electrophoresis with neutral or slightly charged interpenetrating networks to improve DNA separation SO ELECTROPHORESIS LA English DT Article DE DNA electrophoresis; cyclic migration; hernias; polyacrylamide; agarose ID TRANSIENT ELECTRIC BIREFRINGENCE; PULSED-FIELD; AGAROSE GELS; MONTE-CARLO; INVERSION; MOLECULES; DYNAMICS; MIGRATION; MOBILITY; BEHAVIOR AB Toward improving DNA separations, this work reports the effects of high-frequency square-wave AC fields superimposed perpendicular to the direct current (DC) separation field on DNA migration in both polyacrylamide-based interpenetrating networks (IPNs) and in agarose networks. Compared to standard polyacrylamide gels, IPNs allow the separation of larger DNA (9000 bp vs. 5000 bp at 5 V/cm). In novel polyacrylamide-based IPNs, an alternating current (AC) field of 5 Hz increased the maximum DNA size separable. This effect was extended to larger DNA sizes with increasing electric-field strength up to and apparently beyond the power supply-limited maximum electric-field strength of 48 V/cm. The orthogonal AC field also increased mobility. These two results combine to yield a reduction in separation time of up to a factor of 20 in novel polyacrylamide-based IPNs. When negatively charged acrylic-acid groups were incorporated into the IPNs, the use of the AC field changed the DNA-network interaction, which altered the size dependence of DNA mobility. In agarose gels, an AC field of 50 Hz increased the size range separable; however, there was no increase in DNA mobility. There was no change in size dependence of mobility in an AC field when the number of charged groups in the agarose network was increased. Based on results in the literature, possible mechanisms were examined for the effects of the AC field on DNA separation. C1 Univ Calif Berkeley, Dept Chem Engn, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA. RP Blanch, HW (reprint author), Univ Calif Berkeley, Dept Chem Engn, Berkeley, CA 94720 USA. FU NIGMS NIH HHS [1 R01 GM/HG 52351] NR 44 TC 3 Z9 3 U1 1 U2 2 PU WILEY-V C H VERLAG GMBH PI BERLIN PA MUHLENSTRASSE 33-34, D-13187 BERLIN, GERMANY SN 0173-0835 J9 ELECTROPHORESIS JI Electrophoresis PD DEC PY 1998 VL 19 IS 18 BP 3137 EP 3148 DI 10.1002/elps.1150191815 PG 12 WC Biochemical Research Methods; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA 159ZA UT WOS:000078204800014 PM 9932806 ER PT J AU Streets, DG Waldhoff, ST AF Streets, DG Waldhoff, ST TI Biofuel use in Asia and acidifying emissions SO ENERGY LA English DT Article ID ACID-RAIN; ENERGY; DEPOSITION; DIOXIDE; SULFUR AB An inventory of biofuel use in Asia has been developed at the regional level for the year 1990. It is estimated that biofuel use amounts to about 22,000 PJ (1 PJ = 10(15) J), almost 24% of the total energy use in Asia. China and India are the two largest consumers. A relation is developed between the GDP of Asian countries and the percent contribution of biofuels to total primary energy supply. The biofuel energy estimates are used to calculate atmospheric emissions of SO2 and NOx. It is estimated that SO2 emissions from biofuel combustion amount to 1.65 Tg (1 Tg = 10(12) g), about 4.9% of total emissions. The emissions of NOx are estimated to be 1.47 Tg or 7.7% of the total. These energy and emission estimates are designed to be used in the RAINS-Asia computer model, a comprehensive analytical tool used to study energy use in Asia, its effects on-the atmospheric environment, and its subsequent damage to ecosystems. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Argonne Natl Lab, Decis & Informat Sci Div, Argonne, IL 60439 USA. RP Streets, DG (reprint author), Argonne Natl Lab, Decis & Informat Sci Div, 9700 S Cass Ave, Argonne, IL 60439 USA. OI Streets, David/0000-0002-0223-1350 NR 45 TC 53 Z9 62 U1 0 U2 5 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0360-5442 J9 ENERGY JI Energy PD DEC PY 1998 VL 23 IS 12 BP 1029 EP 1042 DI 10.1016/S0360-5442(98)00033-4 PG 14 WC Thermodynamics; Energy & Fuels SC Thermodynamics; Energy & Fuels GA 139FZ UT WOS:000077018500002 ER PT J AU Fisk, WJ De Almeida, AT AF Fisk, WJ De Almeida, AT TI Sensor-based demand-controlled ventilation: a review SO ENERGY AND BUILDINGS LA English DT Article DE demand-controlled; energy; indoor air quality; sensors; ventilation ID INDOOR HUMIDITY; HUMAN HEALTH; ENERGY; IAQ AB With sensor-based demand-controlled ventilation (SBDCV), the rate of ventilation is modulated over time based on the signals from indoor air pollutant or occupancy sensors. SBDCV offers two potential advantages: better control of indoor pollutant concentrations, and lower energy use and peak energy demand. Based on theoretical considerations and on a review of literature, SBDCV has the highest potential to be cost-effective in applications with the following characteristics: (a) a single or small number of pollutants dominate so that ventilation sufficient to control the concentration of the dominant pollutants provides effective control of all other pollutants; (b) large buildings or rooms with unpredictable temporally variable occupancy or pollutant emission; and (c) climates with high heating or cooling loads or locations with expensive energy. At present, most SBDCV systems are based on monitoring and control of carbon dioxide (CO2) concentrations. There is a limited number of well-documented case studies that quantify the energy savings and the cost-effectiveness of SBDCV. The case studies reviewed suggest that in appropriate applications, SBDCV produces significant energy savings with a payback period typically of a few years. (C) 1998 Elsevier Science S.A. All rights reserved. C1 Lawrence Berkeley Lab, Indoor Environm Dept, Berkeley, CA 94720 USA. RP De Almeida, AT (reprint author), Lawrence Berkeley Lab, Indoor Environm Dept, Berkeley, CA 94720 USA. EM aalmeida@isr.uc.pt OI Almeida, Anibal/0000-0002-3641-5174 NR 43 TC 49 Z9 49 U1 2 U2 17 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0378-7788 J9 ENERG BUILDINGS JI Energy Build. PD DEC PY 1998 VL 29 IS 1 BP 35 EP 45 DI 10.1016/S0378-7788(98)00029-2 PG 11 WC Construction & Building Technology; Energy & Fuels; Engineering, Civil SC Construction & Building Technology; Energy & Fuels; Engineering GA 139FW UT WOS:000077018200006 ER PT J AU Lee, E DiBartolomeo, DL Selkowitz, SE AF Lee, E DiBartolomeo, DL Selkowitz, SE TI Thermal and daylighting performance of an automated venetian blind and lighting system in a full-scale private office SO ENERGY AND BUILDINGS LA English DT Article DE windows; lighting; energy-efficiency; thermal measurements; daylighting AB Dynamic envelope/lighting systems have the potential to optimize the perimeter zone energy balance between daylight admission and solar heat gain rejection on a real-time basis, and to increase occupant comfort. Two side-by-side full-scale offices in Oakland, California were built to further develop and test this concept. An automated venetian blind was operated in synchronization with a dimmable electric lighting system to block direct sun, provide the design workplane illuminance, and maximize view. The research program encompassed system design refinements, energy measurements, and human factors tests. In this study, we present lighting energy and cooling load data that were monitored in this facility over the course of a year. Significant energy savings and peak demand reductions were attained with the automated venetian blind/lighting system compared to a static venetian blind with the same dimmable electric lighting system. Correlations between key weather parameters and cooling and lighting were used to illustrate how the dynamic system was able to simultaneously achieve optimization between lighting and cooling end uses under the full range of weather conditions of this sunny, moderate climate. Energy efficiency estimates were conservative since experience shows that conventional daylighting control systems and manually operated shading devices are rarely used effectively in real world applications. (C) 1998 Elsevier Science S.A. All rights reserved. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Environm Energy Technol Div, Bldg Technol Program, Berkeley, CA 94720 USA. RP Lee, E (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Environm Energy Technol Div, Bldg Technol Program, Berkeley, CA 94720 USA. NR 12 TC 71 Z9 72 U1 7 U2 21 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0378-7788 J9 ENERG BUILDINGS JI Energy Build. PD DEC PY 1998 VL 29 IS 1 BP 47 EP 63 DI 10.1016/S0378-7788(98)00035-8 PG 17 WC Construction & Building Technology; Energy & Fuels; Engineering, Civil SC Construction & Building Technology; Energy & Fuels; Engineering GA 139FW UT WOS:000077018200007 ER PT J AU Krackeler, T Schipper, L Sezgen, O AF Krackeler, T Schipper, L Sezgen, O TI Carbon dioxide emissions in OECD service sectors: the critical role of electricity use SO ENERGY POLICY LA English DT Article DE carbon-dioxide emission; service sector; energy-efficiency AB From the early 1970s to mid 1990s, service sector CO2 emissions have increased significantly in OECD countries, despite marked declines in energy intensity. This development is underscored by a widespread shift from fuel use to electricity use in commercial buildings. Service sectors in countries that produce low-carbon electricity, particularly those that operate nuclear- and hydro-powered utilities, have most successfully restrained CO2 emissions. This study analyzes the impact of activity, structure, energy intensity, fuel mix, and utility mix on carbon emissions in the service sector for 13 OECD countries, and contrasts the developments before 1990 with those afterwards. The major findings of this analysis are: (i) Carbon emissions, which rose in 9 of the 13 countries investigated, were bolstered in every country by an expansion of floor area and service sector GDP, (ii) Declines in energy intensity and carbon intensity lessened the magnitude of emissions increases, (iii) Electricity's share of final energy use rose in all 13 countries, but affected carbon emissions quite differently among countries, (iv) After 1990, energy intensity improvements applied less downward pressure on emissions, while reductions in the average carbon content of final energy restrained emissions more strongly. (C) 1999 Published by Elsevier Science Ltd. All rights reserved. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Energy Anal Dept, Berkeley, CA 94720 USA. RP Krackeler, T (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Energy Anal Dept, 1 Cyclotron Rd,Bldg 90-4000, Berkeley, CA 94720 USA. NR 0 TC 17 Z9 18 U1 0 U2 5 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0301-4215 J9 ENERG POLICY JI Energy Policy PD DEC PY 1998 VL 26 IS 15 BP 1137 EP 1152 DI 10.1016/S0301-4215(98)00055-X PG 16 WC Energy & Fuels; Environmental Sciences; Environmental Studies SC Energy & Fuels; Environmental Sciences & Ecology GA 175LZ UT WOS:000079097100004 ER PT J AU Newman, MC McCloskey, JT Tatara, CP AF Newman, MC McCloskey, JT Tatara, CP TI Using metal-ligand binding characteristics to predict metal toxicity: Quantitative ion character-activity relationships (QICARs) SO ENVIRONMENTAL HEALTH PERSPECTIVES LA English DT Article; Proceedings Paper CT Conference on Current Issues of Chemical Mixtures CY AUG 11-13, 1997 CL FT COLLINS, COLORADO SP Colorado State Univ, Natl Inst Environm Hlth Sci Superfund Basic Res Program, Agcy Tox Subst & Dis Registry, US EPA, Off Solid Waste & Emergency Response, US EPA,. Reg VIII Off, USA Ctr Environm Hlth Res, Elect Power Res Inst DE metal; toxicity; prediction; model; ion characteristics ID MICROTOX(R) BIOLUMINESCENCE ASSAY; INVITRO CYTO-TOXICITY; RELATIVE TOXICITY; DAPHNIA-MAGNA; HEAVY-METALS; FRESH-WATER; CELL-LINES; FISH; SOFTNESS AB Ecological risk assessment can be enhanced with predictive models for metal toxicity. Modelings of published data were done under the simplifying assumption that intermetal trends in toxicity reflect relative metal-ligand complex stabilities. This idea has been invoked successfully since 1904 but has yet to be applied widely in quantitative ecotoxicology. Intermetal vends in toxicity were successfully modeled with ion characteristics reflecting metal binding to ligands for a wide range of effects. Most models were useful for predictive purposes based on an F-ratio criterion and cross-validation, but anomalous predictions did occur in speciation was ignored in general, models for metals with the same valence (i.e., divalent metals) were better than those combining mono-, di-, and trivalent metals. The softness parameter (sigma(p)) and the absolute value of the log of the first hydrolysis constant (\log K-OH\) were especially useful in model construction. Also, Delta E-o contributed substantially to several of the two-variable models. In contrast, quantitative attempts to predict metal interactions in binary mixtures based on metal-ligand complex stabilities were not successful. C1 Virginia Inst Marine Sci, Coll William & Mary, Dept Environm Sci, Gloucester Point, VA 23062 USA. US Fish & Wildlife Serv, Gloucester Point, VA USA. Univ Georgia, Savannah River Ecol Lab, Aiken, SC USA. RP Newman, MC (reprint author), Virginia Inst Marine Sci, Coll William & Mary, Dept Environm Sci, Gloucester Point, VA 23062 USA. EM newman@vims.edu NR 42 TC 29 Z9 31 U1 0 U2 11 PU US DEPT HEALTH HUMAN SCIENCES PUBLIC HEALTH SCIENCE PI RES TRIANGLE PK PA NATL INST HEALTH, NATL INST ENVIRONMENTAL HEALTH SCIENCES, PO BOX 12233, RES TRIANGLE PK, NC 27709-2233 USA SN 0091-6765 J9 ENVIRON HEALTH PERSP JI Environ. Health Perspect. PD DEC PY 1998 VL 106 SU 6 BP 1419 EP 1425 PG 7 WC Environmental Sciences; Public, Environmental & Occupational Health; Toxicology SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Toxicology GA 156NT UT WOS:000078008100022 PM 9860900 ER PT J AU Pounds, JG Leggett, RW AF Pounds, JG Leggett, RW TI The ICRP age-specific biokinetic model for lead: Validations, empirical comparisons, and explorations SO ENVIRONMENTAL HEALTH PERSPECTIVES LA English DT Article; Proceedings Paper CT Conference on Current Issues of Chemical Mixtures CY AUG 11-13, 1997 CL FT COLLINS, COLORADO SP Colorado State Univ, Natl Inst Environm Hlth Sci Superfund Basic Res Program, Agcy Tox Subst & Dis Registry, US EPA, Off Solid Waste & Emergency Response, US EPA,. Reg VIII Off, USA Ctr Environm Hlth Res, Elect Power Res Inst DE lead toxicity; lead; biokinetic; toxicokinetic; PBPK; chelation; DMSA; skeleton; bone ID PHYSIOLOGICALLY-BASED MODELS; BONE-SEEKING ELEMENTS; X-RAY-FLUORESCENCE; OCCUPATIONAL EXPOSURE; CHELATION-THERAPY; UNITED-STATES; BLOOD LEAD; CHILDREN; SKELETAL; MOBILIZATION AB The objective of this manuscript is to provide a description of the International Commission for Radiation Protection (ICRP) model and a comparison to other models (the integrated exposure uptake biokinetic [IEUBK] and O'Flaherty models), including the software used with the models, and a comparison of the model predictions for selected situations. The ICRP biokinetic model for Pb is a multicompartmental model for Pb uptake and disposition in children and in adults. The model describes deposition and retention of absorbed Pb in numerous tissues, removal from tissues to plasma, and movement along various routes of excretion. Long-term skeletal behavior of Pb is described in terms of age-specific rates of restructuring of compact and trabecular bone. The ICRP model is more flexible and has wider applicability than the IEUBK model. The major disadvantages are that application of the computer model requires some basic computer skills, and the user must convert the Pb concentrations in food, air, soil, dust, paint, or other media to the amount of Pb ingested or inhaled per day. Direct comparisons between the ICRP model and the IEUBK model are provided by modeling blood Pb levels using the IEUBK v0.99d default Pb uptakes and intake values. The model is used to simulate occupational exposure cases and a controlled Pb inhalation experiment in adult humans. Finally, use of the model to explore situations with limited data is illustrated by simulating the kinetics and disposition of Pb during acute Pb poisoning and chelation therapy in a child. C1 Wayne State Univ, Inst Chem Toxicol, Detroit, MI 48201 USA. Oak Ridge Natl Lab, Div Life Sci, Oak Ridge, TN USA. RP Pounds, JG (reprint author), Wayne State Univ, Inst Chem Toxicol, 2727 2nd Ave,Room 4000, Detroit, MI 48201 USA. EM j.pounds@wayne.edu OI Pounds, Joel/0000-0002-6616-1566 FU NIEHS NIH HHS [ES04040] NR 28 TC 21 Z9 21 U1 1 U2 7 PU US DEPT HEALTH HUMAN SCIENCES PUBLIC HEALTH SCIENCE PI RES TRIANGLE PK PA NATL INST HEALTH, NATL INST ENVIRONMENTAL HEALTH SCIENCES, PO BOX 12233, RES TRIANGLE PK, NC 27709-2233 USA SN 0091-6765 J9 ENVIRON HEALTH PERSP JI Environ. Health Perspect. PD DEC PY 1998 VL 106 SU 6 BP 1505 EP 1511 PG 7 WC Environmental Sciences; Public, Environmental & Occupational Health; Toxicology SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Toxicology GA 156NT UT WOS:000078008100032 PM 9860909 ER PT J AU Garrett, RM Pickering, IJ Haith, CE Prince, RC AF Garrett, RM Pickering, IJ Haith, CE Prince, RC TI Photooxidation of crude oils SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Article ID RAY-ABSORPTION-SPECTROSCOPY; PHOTO-OXIDATION PRODUCTS; K-EDGE; SEAWATER; SUNLIGHT; SITE; OXIDASE; BEACH AB Photooxidation is a potentially significant process in the degradation of crude oil spilled at sea. Moreover, a fundamental understanding of the effect of photochemical degradation on crude oil is a prerequisite for providing an accurate description of the recent history and potential fate of oil spilled in a marine environment. In this report we examine the effect of ultraviolet illumination on crude oil using a variety of techniques including gas chromatography/mass spectroscopy and X-ray absorption spectroscopy. The saturated compounds are resistant, but the aromatic compounds are particularly sensitive to photooxidation. Greater size and increasing alkyl substitution increase the sensitivity of aromatic compounds to photochemical oxidation. The photooxidized products appear in the resin and polar fractions as determined by thin-layer chromatography. Thus, the effect of photooxidation is distinctly different from that of biodegradation, where larger and more substituted compounds are more resistant to degradation. Perhaps surprisingly, X-ray absorption spectroscopy indicates that the aliphatic sulfur compounds are more readily oxidized than the thiophenic compounds with the sulfur being oxidized to sulfoxides, sulfones, sulfonates, and sulfates in approximately equal amounts. C1 Exxon Res & Engn Co, Annandale, NJ 08801 USA. Stanford Univ, Stanford Synchrotron Radiat Lab, SLAC, Stanford, CA 94309 USA. RP Garrett, RM (reprint author), Exxon Res & Engn Co, Route 22 E, Annandale, NJ 08801 USA. EM rmgarre@erenj.com RI Pickering, Ingrid/A-4547-2013; OI Pickering, Ingrid/0000-0002-0936-2994 NR 32 TC 111 Z9 124 U1 2 U2 42 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0013-936X J9 ENVIRON SCI TECHNOL JI Environ. Sci. Technol. PD DEC 1 PY 1998 VL 32 IS 23 BP 3719 EP 3723 DI 10.1021/es980201r PG 5 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 143XH UT WOS:000077282500030 ER PT J AU Gaffney, JS Marley, NA Martin, RS Dixon, RW Reyes, LG Popp, CJ AF Gaffney, JS Marley, NA Martin, RS Dixon, RW Reyes, LG Popp, CJ TI Response to comment on "Potential air quality effects of using ethanol-gasoline fuel blends: A field study in Albuquerque, New Mexico" SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Letter ID PEROXYACETYL NITRATE C1 Argonne Natl Lab, Div Environm Res, Argonne, IL 60439 USA. New Mexico Inst Min & Technol, Dept Mineral & Environm Engn, Socorro, NM 87801 USA. New Mexico Inst Min & Technol, Dept Chem, Socorro, NM 87801 USA. RP Gaffney, JS (reprint author), Argonne Natl Lab, Div Environm Res, Bldg 203,9700 S Cass Ave, Argonne, IL 60439 USA. NR 13 TC 4 Z9 4 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0013-936X J9 ENVIRON SCI TECHNOL JI Environ. Sci. Technol. PD DEC 1 PY 1998 VL 32 IS 23 BP 3842 EP 3844 DI 10.1021/es982011m PG 3 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 143XH UT WOS:000077282500052 ER PT J AU Stern, EA Donato, K Jones, KW Clesceri, NL AF Stern, EA Donato, K Jones, KW Clesceri, NL TI Processing contaminated dredged material from the Port of New York New Jersey SO ESTUARIES LA English DT Article AB Shipping activities in the Port of New York-New Jersey are currently threatened by restrictions on dredging of navigational channels and private berthing areas because of concerns about the environmental effects caused by ocean disposal of the dredged material. Current proposals for solutions to the problem include ocean disposal of uncontaminated material, use of confined disposal facilities (both upland facilities and containment islands), subaqueous borrow pits, and processing and treatment for contaminated materials. A project to produce a complete "treatment train" for processing and decontaminating dredged material is described. The work is divided into several phases: treatability studies of commercial and nonproprietary technologies at volumes of 19 liters (bench scale) and up to 19 m(3) (pilot scale); specification of a treatment train; and implementation of a large-scale facility that can process 76,000-382,000 m(3) of dredged material per year. The goal is to achieve operational status for the facility by the end of 1999. C1 Brookhaven Natl Lab, Dept Appl Sci, Upton, NY 11973 USA. US EPA, Div Environm Planning & Protect, Placed Based Protect Branch, New York, NY 10007 USA. USA, Corps Engineers, NY Dist Corps Engineers, N Atlantic Div,Planning Div,Environm Sect, New York, NY 10278 USA. Rensselaer Polytech Inst, Dept Environm & Energy Engn, Troy, NY 12180 USA. RP Jones, KW (reprint author), Brookhaven Natl Lab, Dept Appl Sci, Bldg 901A, Upton, NY 11973 USA. EM kwj@bnl.gov NR 8 TC 4 Z9 4 U1 2 U2 4 PU ESTUARINE RESEARCH FEDERATION PI PORT REPUBLIC PA 2018 DAFFODIL, PO BOX 510, PORT REPUBLIC, MD 20676 USA SN 0160-8347 J9 ESTUARIES JI Estuaries PD DEC PY 1998 VL 21 IS 4A BP 646 EP 651 DI 10.2307/1353302 PG 6 WC Environmental Sciences; Marine & Freshwater Biology SC Environmental Sciences & Ecology; Marine & Freshwater Biology GA 169KD UT WOS:000078746200014 ER PT J AU Walsh, MA McCarthy, A O'Farrell, PA McArdle, P Cunningham, PD Mayhew, SG Higgins, TM AF Walsh, MA McCarthy, A O'Farrell, PA McArdle, P Cunningham, PD Mayhew, SG Higgins, TM TI X-ray crystal structure of the Desulfovibrio vulgaris (Hildenborough) apoflavodoxin-riboflavin complex SO EUROPEAN JOURNAL OF BIOCHEMISTRY LA English DT Article DE flavodoxin; riboflavin; electron transfer; X-ray crystal structure; Desulfovibrio vulgaris ID MONONUCLEOTIDE BINDING-SITE; OXIDIZED FLAVODOXIN; ANGSTROM RESOLUTION; FLAVIN BINDING; PROTEIN; 3',5'-BISPHOSPHATE; 5'-PHOSPHATE; POTENTIALS; COFACTOR; ERRORS AB The apoprotein of flavodoxin from Desulfovibrio vulgaris forms a complex with riboflavin. The ability to bind riboflavin distinguishes this flavodoxin from other short-chain flavodoxins which require the phosphate of FMN for flavin binding. The redox potential of the semiquinone/hydroquinone couple of the bound riboflavin is 180 mV less negative than the corresponding complex with FICIN, To elucidate the binding of riboflavin, the complex has been crystallized and the crystal structure solved by molecular replacement using native flavodoxin as a search model to a resolution of 0.183 nm. Compared to the FMN complex, the hydrogen-bonding network at the isoalloxazine sub-site of the riboflavin complex is severely disrupted by movement of the loop residues Ser58 - Ile64 (60-loop) which contact the isoalloxazine by over 0.35 nm, and by a small displacement of the isoalloxazine moiety. The 60-loop movement away from the flavin increases the solvent exposure of the flavin-binding site. The conformation of the site at which 5'-phosphate of FMN normally binds is similar in the two complexes, but in the riboflavin complex a sulphate or phosphate ion from the crystallization buffer occupies the space. This causes small structural perturbations in the phosphate-binding site. The flexibility of the 60-loop in D, vulgar is flavodoxin appears to be a contributing factor to the binding of riboflavin by the apoprotein, and a feature that distinguishes the protein from other 'short chain' flavodoxins. In the absence of the terminal phosphate group, free movement at the 5'-OH group of the ribityl chain can occur. Thus, the 5'-phosphate of FMN secures the cofactor at the binding site and positions it optimally. The structural changes which occur in the 60-loop in the riboflavin complex probably account for most of the positive shift that is observed in the midpoint potential of the semiquinone/hydroquinone couple of the riboflavin complex compared to that of the FMN complex. C1 Univ Coll, Dept Chem, Galway, Ireland. Univ Coll, Dept Biochem, Dublin, Ireland. RP Walsh, MA (reprint author), Argonne Natl Lab, Bldg 202,9700 S Cass Ave, Argonne, IL 60439 USA. EM walsh@anl.gov RI Walsh, Martin/I-1566-2013 OI Walsh, Martin/0000-0001-5683-1151 NR 42 TC 31 Z9 33 U1 0 U2 1 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0014-2956 J9 EUR J BIOCHEM JI Eur. J. Biochem. PD DEC 1 PY 1998 VL 258 IS 2 BP 362 EP 371 DI 10.1046/j.1432-1327.1998.2580362.x PG 10 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 145DA UT WOS:000077354700010 PM 9874201 ER PT J AU Alde, D Binon, FG Boutemeur, M Bricman, C Donskov, SV Gouanere, M Inyakin, AV Inaba, S Kachanov, VA Khaustov, GV Knapp, EA Kondashov, AA Lednev, AA Lishin, VA Peigneux, JP Poulet, M Prokoshkin, YD Sadovsky, SA Samoylenko, VD Shagin, PM Singovsky, AV Stroot, JP Sugonyaev, VP Takamatsu, K Tsuru, T AF Alde, D Binon, FG Boutemeur, M Bricman, C Donskov, SV Gouanere, M Inyakin, AV Inaba, S Kachanov, VA Khaustov, GV Knapp, EA Kondashov, AA Lednev, AA Lishin, VA Peigneux, JP Poulet, M Prokoshkin, YD Sadovsky, SA Samoylenko, VD Shagin, PM Singovsky, AV Stroot, JP Sugonyaev, VP Takamatsu, K Tsuru, T TI Study of the pi(0)pi(0)-system with the GAMS-4000 spectrometer at 100 GeV/c SO EUROPEAN PHYSICAL JOURNAL A LA English DT Article ID AMPLITUDE; CHANNEL; SYSTEM; PI AB The pi(o)-pi(o)-system produced in the charge exchange pi(-) p-reaction at 100 GeV/c has been studied. The experiment was performed at the CERN SPS accelerator with the multiphoton hodoscope spectrometer GAMS-4000. A partial wave analysis was carried out in the mass range from 0.8 GeV to 3.0 GeV at -t < 0.2 (GeV/c)(2) with the S, D, G and J waves. The S-wave exhibits rather complicated behaviour with a series of four bumps separated by three dips, at 1 GeV 1.5 GeV and 2 Gev, which give the evidence for several scalar resonances. Clear peaks corresponding to the f(2)(1270), f(4)(2050) and f(6)(2510) mesons are seen in the higher waves. All the three mesons are produced via a dominating one pion t-channel exchange. The parameters and production cross sections of these mesons are measured. C1 Inst High Energy Phys, Protvino 142284, Russia. Inst Interuniv Sci Nucl, B-1050 Brussels, Belgium. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87544 USA. Lab Annecy Phys Particules, F-74019 Annecy Le Vieux, France. Kek Nat Lab High Energy Phys, Tsukuba, Ibaraki 305, Japan. CERN, CH-1211 Geneva 23, Switzerland. Free Univ Brussels, B-1050 Brussels, Belgium. Miyazaki Univ, Miyazaki 88921, Japan. RP Alde, D (reprint author), Inst High Energy Phys, Protvino 142284, Russia. NR 31 TC 31 Z9 31 U1 0 U2 0 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 1434-6001 J9 EUR PHYS J A JI Eur. Phys. J. A PD DEC PY 1998 VL 3 IS 4 BP 361 EP 371 DI 10.1007/s100500050190 PG 11 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 150EX UT WOS:000077651600010 ER PT J AU DeWoody, JA Fletcher, DE Wilkins, SD Nelson, WS Avise, JC AF DeWoody, JA Fletcher, DE Wilkins, SD Nelson, WS Avise, JC TI Molecular genetic dissection of spawning, parentage, and reproductive tactics in a population of redbreast sunfish, Lepomis auritus SO EVOLUTION LA English DT Article DE cuckoldry; maternity; mating system; microsatellites; paternity; polygyny; sexual selection ID MALE BLUEGILL SUNFISH; MUTATION; MICROSATELLITES; MACROCHIRUS; PROPORTION; STRATEGIES; SATELLITES; CUCKOLDRY; EVOLUTION; SNEAKERS AB Despite a great diversity of reproductive behaviors in fishes, few studies have examined the genetic consequences of alternative reproductive tactics. Here we develop and employ microsatellite markers to assess genetic paternity and maternity of progeny cohorts in a population of redbreast sunfish (Lepomis auritus), a species in which males build and tend nests. Nearly 1000 progeny from 25 nests, plus nest-attendant males and nearby adults, were genotyped at microsatellite loci that displayed more than 18 alleles each. The genetic data demonstrate that multiple females (at least two to six) spawned in each nest, their offspring were spatially dispersed across a nest, and more than 90% of the young were shed by the attendant male. However, about 40% of the nests also showed genetic evidence of low-level reproductive parasitism, and two nests were tended by males that had fathered none of the sampled offspring. Genetically deduced reproductive behaviors in this population of redbreast sunfish contrast with those reported previously in bluegill sunfish (L. macrochirus) wherein heteromorphic males specialized for parasitism or for parental care coexist in high frequency. Thus, nest-parasitic reproductive behaviors in fishes appear to be evolutionary labile. C1 Univ Georgia, Dept Genet, Athens, GA 30602 USA. Savannah River Ecol Lab, Aiken, SC 29802 USA. RP DeWoody, JA (reprint author), Univ Georgia, Dept Genet, Athens, GA 30602 USA. RI DeWoody, James/C-4909-2008 OI DeWoody, James/0000-0002-7315-5631 NR 30 TC 63 Z9 63 U1 0 U2 11 PU SOC STUDY EVOLUTION PI LAWRENCE PA 810 E 10TH STREET, LAWRENCE, KS 66044 USA SN 0014-3820 J9 EVOLUTION JI Evolution PD DEC PY 1998 VL 52 IS 6 BP 1802 EP 1810 DI 10.2307/2411350 PG 9 WC Ecology; Evolutionary Biology; Genetics & Heredity SC Environmental Sciences & Ecology; Evolutionary Biology; Genetics & Heredity GA 157TA UT WOS:000078076700023 ER PT J AU Stockwell, CA Mulvey, M AF Stockwell, CA Mulvey, M TI Phosphogluconate dehydrogenase polymorphism and salinity in the White Sands pupfish SO EVOLUTION LA English DT Article DE Cyprinodon tularosa; Pgdh; phosphogluconate dehydrogenase; salinity; selection; translocation; White Sands pupfish ID LDH-B GENOTYPE; FUNDULUS-HETEROCLITUS; DROSOPHILA-MELANOGASTER; NATURAL-SELECTION; 6-PHOSPHOGLUCONATE DEHYDROGENASE; PHYSIOLOGICAL-BASIS; GENETIC-VARIATION; ENZYME GENOTYPES; DNA VARIATION; LOCI AB The phosphogluconate dehydrogenase (Pgdh) locus is the only polymorphic allozyme locus observed among 37 loci examined in all four populations of a New Mexico state Endangered species, the White Sands pupfish (Cyprinodon tularosa). We report evidence suggesting that this polymorphism may be associated with salinity. Salinity levels vary widely within and between habitats occupied by White Sands pupfish. The frequency of the Pgdh(100) allozyme was correlated with salinity but not with temperature. Frequency of Pgdh(100) differed between low (3.76 parts per thousand (ppt)) and high (9.23 ppt) salinity sites at Malpais Spring despite no obvious barriers to fish movement. Frequencies of Pgdh(100) in two introduced populations differed from that of the presumptive founding stock and correlated with salinity in the current habitats. C1 N Dakota State Univ, Dept Zool, Fargo, ND 58105 USA. Savannah River Ecol Lab, Aiken, SC 29802 USA. RP Stockwell, CA (reprint author), N Dakota State Univ, Dept Zool, Stevens Hall, Fargo, ND 58105 USA. EM cstockwe@plains.nodak.edu NR 48 TC 18 Z9 18 U1 0 U2 3 PU SOC STUDY EVOLUTION PI LAWRENCE PA 810 E 10TH STREET, LAWRENCE, KS 66044 USA SN 0014-3820 J9 EVOLUTION JI Evolution PD DEC PY 1998 VL 52 IS 6 BP 1856 EP 1860 DI 10.2307/2411357 PG 5 WC Ecology; Evolutionary Biology; Genetics & Heredity SC Environmental Sciences & Ecology; Evolutionary Biology; Genetics & Heredity GA 157TA UT WOS:000078076700030 ER PT J AU Gao, HJ Canright, GS Pang, SJ Sandler, IM Xue, ZQ Zhang, ZY AF Gao, HJ Canright, GS Pang, SJ Sandler, IM Xue, ZQ Zhang, ZY TI Unique dendritic patterns in organic thin films: Experiments and modeling SO FRACTALS-COMPLEX GEOMETRY PATTERNS AND SCALING IN NATURE AND SOCIETY LA English DT Article ID IONIZED-CLUSTER-BEAM; FRACTAL PATTERNS; GROWTH; POLYMER; AGGREGATION; SURFACES AB We present the formation of unique and striking dendritic "seahorse" patterns in the growth of fullerene-tetracyanoquinodimethane (C-60-TCNQ) or pure TCNQ thin films. The films were fabricated by an ionized-cluster-beam deposition method. Energetic neutral and charged clusters were deposited on amorphous carbon substrates. Transmission electron microscopy reveals that the elemental pattern is a "seahorse" - that is, an S-shaped form, with "fins" on the outer edges of the curved arms forming the S. Such forms possess an approximate symmetry under rotations by pi, but strongly break two-dimensional inversion symmetry. A novel formation mechanism is proposed, involving the aggregation of neutral and charged clusters, such that some electrostatic charge is trapped on each growing island. This charge gives rise to a long-range field which biases the growth in a nontrivial way. The broken symmetry arises from the strong amplification of noise in the diffusive aggregation process by the effects of the electrostatic field - that is, the symmetry breaking is spontaneous. This picture is tested by applying a transverse electric field during growth: for sufficiently strong fields, the S-shaped "seahorses" lose their curvature, while retaining the feature of having two main arms. These results demonstrate the importance of electrostatic effects in the growth process, and are consistent with the growth mechanism described here. C1 Chinese Acad Sci, Beijing Lab Vacuum Phys, Beijing 100080, Peoples R China. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. Peking Univ, Dept Elect, Beijing 100871, Peoples R China. RP Gao, HJ (reprint author), Chinese Acad Sci, Beijing Lab Vacuum Phys, Beijing 100080, Peoples R China. NR 36 TC 9 Z9 12 U1 2 U2 12 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA JOURNAL DEPT PO BOX 128 FARRER ROAD, SINGAPORE 912805, SINGAPORE SN 0218-348X J9 FRACTALS JI Fractals-Complex Geom. Patterns Scaling Nat. Soc. PD DEC PY 1998 VL 6 IS 4 BP 337 EP 350 DI 10.1142/S0218348X98000390 PG 14 WC Mathematics, Interdisciplinary Applications; Multidisciplinary Sciences SC Mathematics; Science & Technology - Other Topics GA 155JN UT WOS:000077943400005 ER PT J AU Reich, PB Ellsworth, DS Walters, MB AF Reich, PB Ellsworth, DS Walters, MB TI Leaf structure (specific leaf area) modulates photosynthesis-nitrogen relations: evidence from within and across species and functional groups SO FUNCTIONAL ECOLOGY LA English DT Article DE functional groups; net photosynthesis; nitrogen; specific leaf area ID USE EFFICIENCY; LIFE-SPAN; LEAVES; CO2; PLANTS; WATER; MASS; CARBON; ECOPHYSIOLOGY; ASSIMILATION AB 1. Net photosynthetic capacity (A(max), defined as light-saturated net photosynthesis under near optimal ambient environmental conditions) of mature leaves often depends on the level of leaf nitrogen (N), but an assortment of relationships between these variables has been observed in studies of diverse plant species. Variation in leaf structure has been identified as an important factor associated with differences between the area- and mass-based expressions of the A(max)-N relationship. In this paper we test the hypothesis that leaf structure, quantified using a measure of leaf area displayed per unit dry mass invested [specific leaf area (SLA)], is more than just a conversion factor, but itself can influence A(max)-N relationships. We test this using several kinds of comparisons, based on field data for 107 species from sites representing six biomes and On literature data for 162 species from an equally diverse set of biomes. 2. Species and genera with thicker and/or denser leaves (lower SLA) consistently have flatter slopes of the A(max)-N (mass-based) relationship than those with higher SLA. These and all other contrasts usually applied as well using area-based expressions, although such relationships were less consistent and weaker overall. A steeper slope indicates greater incremental change in A(max) per unit variation in N. 3. Functional groups (e.g. needle-leafed evergreen trees, broad-leafed trees or shrubs, forbs) show the same patterns: groups with lower SLA have lower A(max)-N slopes. Functional groups differ in mean leaf traits as well as in A(max)-N relationships. Forbs have the highest SLA and mass-based N and A(max), followed by deciduous species (whether needle-leafed or broad-leafed, shrub or tree), with lowest values in evergreen species (again regardless of leaf type or functional group). 4. Interspecific variation in mass-based A(max) is highly significantly related to the combination of leaf N and SLA (r(2) = 0.86), At any value of leaf N, A(max) increases with increasing SLA and at any value of SLA, A(max) increases with increasing leaf N. Because this relationship, between A(max) and the combination of N and SLA, is similar in two independent data sets, and as well, across broad taxonomic and geographic gradients, we hypothesize that it is universal in nature. Therefore, for broad interspecific contrasts among dicotyledons in any biome, we can reasonably well predict A(max) based on the combination of SLA and leaf N. These findings have important implications for convergent evolution of leaf adaptation and great potential utility in models of global vegetation functioning. C1 Univ Minnesota, Dept Forest Resources, St Paul, MN 55108 USA. Brookhaven Natl Lab, Dept Appl Sci, Upton, NY 11973 USA. Michigan State Univ, Dept Forestry, E Lansing, MI 48824 USA. RP Reich, PB (reprint author), Univ Minnesota, Dept Forest Resources, St Paul, MN 55108 USA. OI Ellsworth, David/0000-0002-9699-2272 NR 39 TC 266 Z9 284 U1 10 U2 137 PU BLACKWELL SCIENCE LTD PI OXFORD PA P O BOX 88, OSNEY MEAD, OXFORD OX2 0NE, OXON, ENGLAND SN 0269-8463 J9 FUNCT ECOL JI Funct. Ecol. PD DEC PY 1998 VL 12 IS 6 BP 948 EP 958 DI 10.1046/j.1365-2435.1998.00274.x PG 11 WC Ecology SC Environmental Sciences & Ecology GA 165NA UT WOS:000078526400011 ER PT J AU Yoshiura, K Machida, J Daack-Hirsch, S Patil, SR Ashworth, LK Hecht, JT Murray, JC AF Yoshiura, K Machida, J Daack-Hirsch, S Patil, SR Ashworth, LK Hecht, JT Murray, JC TI Characterization of a novel gene disrupted by a balanced chromosomal translocation t(2;19)(q11.2;q13.3) in a family with cleft lip and palate SO GENOMICS LA English DT Article ID GROWTH FACTOR-ALPHA; REGION; ASSOCIATION; CLONING; MAP; IDENTIFICATION; SEQUENCES; LINKAGE; MARKERS; LOCUS AB Cleft lip with or without cleft palate is a common birth defect that is genetically complex. The nonsyndromic forms have been studied genetically using linkage and candidate-gene association studies with only partial success in defining the loci responsible for orofacial clefting. Loci for nonsyndromic cases have been suggested on 2p13, 4q31, 6p24, 17q21-q24, and 19q13.2. Recently, we identified a family in which cleft lip and palate segregated in two of three generations with a balanced chromosomal translocation t(2; 19)(q11.2;q13.3). We used a positional-cloning strategy to identify a novel gene disrupted by the translocation on chromosome 19. Eight rare (q < 0.01) and nine common (q > 0.01) variants of this gene were detected in the DNA of 74 unrelated cases of cleft lip and/or cleft palate; no variants associated significantly with clefting, suggesting that this gene is not a major contributor to abnormal craniofacial development. This gene, CLPTM1, was ubiquitously expressed on Northern blots containing RNA from adult tissues and in wholemount in situ hybridization of day 10 to 12 mouse embryos. CLPTM1 encodes a transmembrane protein and has strong homology to two Caenorhabditis elegans genes, suggesting that CLPTM1 may belong to a new gene family. (C) 1998 Academic Press. C1 Univ Iowa, Dept Pediat, Iowa City, IA 52242 USA. Univ Iowa, Dept Sci Biol, Iowa City, IA 52242 USA. Aichi Gakuin Univ, Sch Dent, Dept Oral & Maxillofacial Surg 2, Nagoya, Aichi 464, Japan. Univ Calif Lawrence Livermore Natl Lab, Ctr Human Genome, Livermore, CA 94550 USA. Univ Texas, Sch Med, Dept Pediat, Houston, TX 77225 USA. RP Murray, JC (reprint author), Univ Iowa, Dept Pediat, Iowa City, IA 52242 USA. EM jeff-murray@uiowa.edu FU NIDCR NIH HHS [DE-08559]; NIDDK NIH HHS [DK-25295] NR 39 TC 45 Z9 48 U1 0 U2 1 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0888-7543 J9 GENOMICS JI Genomics PD DEC 1 PY 1998 VL 54 IS 2 BP 231 EP 240 DI 10.1006/geno.1998.5577 PG 10 WC Biotechnology & Applied Microbiology; Genetics & Heredity SC Biotechnology & Applied Microbiology; Genetics & Heredity GA 145BF UT WOS:000077350500005 PM 9828125 ER PT J AU Peters, LL Weier, HUG Walensky, LD Snyder, SH Parra, M Mohandas, N Conboy, JG AF Peters, LL Weier, HUG Walensky, LD Snyder, SH Parra, M Mohandas, N Conboy, JG TI Four paralogous protein 4.1 genes map to distinct chromosomes in mouse and human SO GENOMICS LA English DT Article ID HEREDITARY ELLIPTOCYTOSIS; MESSENGER-RNA; GENOME AB Four highly conserved members of the skeletal protein 4.1 gene family encode a diverse array of protein isoforms via tissue-specific transcription and developmentally regulated alternative pre-mRNA splicing. In addition do the prototypical red Mood cell 4.1R (human gene symbol EPB41,) these include two homologues that are strongly expressed in the brain (4.1N, EPB41L1; and 4.1B, EPB41L3) and another that is widely expressed in many tissues (4.1B, EPB41L2). As part of a study on the structure and evolution of the 4.1 genes in human and mouse, we have now completed the chromosomal mapping of their respective loci by reporting the localization of mouse 4.1N, 4.1G, and 4.1B, as well as human 4.1B. For the mouse 4.1 genes, Southern blot analysis of RFLPs in The Jackson Laboratory ESS interspecific backcross yielded the following assignments: 4.1N (Epb4.1l1,) chromosome 2; 4.1G (Epb4.1l2,) chromosome 10; and 4.1B (Epb4.1l3,) mouse chromosome 17. Human 4.1B was physically mapped to chromosome 18p11 using fluorescence in situ hybridization. All of the mouse genes mapped within or adjacent to regions of conserved synteny with corresponding human chromosomes. We conclude that a set of four paralogous 4.1 genes has been evolutionarily conserved in rodents and primates. (C) 1988 Academic Press. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, Berkeley, CA 94720 USA. Jackson Lab, Bar Harbor, ME 04609 USA. Johns Hopkins Univ, Sch Med, Dept Neurosci, Baltimore, MD 21205 USA. RP Conboy, JG (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, MS 74-174, Berkeley, CA 94720 USA. EM jgconboy@lbl.gov FU NHLBI NIH HHS [R01 HL055321, HL55321]; NIDDK NIH HHS [DK32094] NR 20 TC 39 Z9 41 U1 0 U2 1 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0888-7543 J9 GENOMICS JI Genomics PD DEC 1 PY 1998 VL 54 IS 2 BP 348 EP 350 DI 10.1006/geno.1998.5537 PG 3 WC Biotechnology & Applied Microbiology; Genetics & Heredity SC Biotechnology & Applied Microbiology; Genetics & Heredity GA 145BF UT WOS:000077350500020 PM 9828140 ER PT J AU Dodson, A DePaolo, DJ Kennedy, BM AF Dodson, A DePaolo, DJ Kennedy, BM TI Helium isotopes in lithospheric mantle: Evidence from Tertiary basalts of the western USA SO GEOCHIMICA ET COSMOCHIMICA ACTA LA English DT Article ID RIO-GRANDE RIFT; UNITED-STATES; LONG VALLEY; CRUSTAL CONTAMINATION; CONTINENTAL BASALTS; THINNING BENEATH; OCEANIC ISLANDS; VOLCANIC-ROCKS; FLOOD BASALTS; TRACE-ELEMENT AB The isotopic compositions of He, Sr, and Nd were measured in Tertiary-age basalts from the Basin and Range province of the western USA to evaluate models for the He isotopic character of subcontinental mantle lithosphere (SCML) and assess the role of recycled SCML in models of mantle evolution. Previous isotopic and trace element measurements suggested that most of these basalts were formed by melting of SCML. He-3/He-4 ratios, measured by in-vacuo crushing of olivine phenocrysts, vary from 2.9 to 7.8 times the atmospheric value (2.9 to 7.8 Ra) consistently below the MORE value of 8.7 +/- 0.5 Ra. The lowest R/Ra values, associated with low epsilon(Nd), high Sr-87/Sr-86, and high La/Nb, are attributable to lithospheric mantle, and indicate that SCML is not dominated by MORE-type He, nor by high R/Ra, plume-type He. Consideration of geographic variability indicates there are two, and possibly three, distinct regions of SCML with differing He isotopic characteristics. SCML beneath the eastern Sierra Nevada is inferred to have He-3/He-4 of similar to 5.5 Ra and a He/Nd ratio slightly less than MORE-type mantle; SCML beneath the central Basin and Range has He-3/He-4 of similar to 4 Ra and a higher He/Nd ratio than MORE-type mantle. The SCML under southwestern Utah shows less systematic correlation of He isotopes with other geochemical parameters, but also has a lower bound R/Ra value of about 4 Ra. The inferred SCML helium ratios are consistent with retention of radiogenic He-4 over 800 Ma for the eastern Sierra Nevada and 1700 Ma for the other two regions. The results are not consistent with models of He infiltration from the underlying asthenosphere and suggest the lithosphere of the Basin and Range region was not delaminated during the early Tertiary. The He, Sr, Nd, and Pb isotopic compositions inferred for the SCML of the southwestern USA are a reasonably good match to the characteristics of the EMII component of mantle heterogeneity identified in oceanic island basalts. High R/Ra mantle reservoirs identified in these basalts are not likely to represent recycled SCML. Copyright (C) 1998 Elsevier Science Ltd. C1 Univ Calif Berkeley, Berkeley Ctr Isotope Geochem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Geol & Geophys, Berkeley, CA 94720 USA. Ernesto Orlando Lawrence Berkeley Natl Lab, Div Earth Sci, Berkeley, CA 94720 USA. RP Dodson, A (reprint author), Univ Calif Berkeley, Berkeley Ctr Isotope Geochem, Berkeley, CA 94720 USA. NR 71 TC 31 Z9 35 U1 0 U2 4 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0016-7037 J9 GEOCHIM COSMOCHIM AC JI Geochim. Cosmochim. Acta PD DEC PY 1998 VL 62 IS 23-24 BP 3775 EP 3787 DI 10.1016/S0016-7037(98)00267-1 PG 13 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 192LX UT WOS:000080081300014 ER PT J AU McComas, DJ Bame, SJ Barker, PL Delapp, DM Feldman, WC Gosling, JT Santiago, E Skoug, RM Tokar, RL Riley, P Phillips, JL Griffee, JW AF McComas, DJ Bame, SJ Barker, PL Delapp, DM Feldman, WC Gosling, JT Santiago, E Skoug, RM Tokar, RL Riley, P Phillips, JL Griffee, JW TI An unusual coronal mass ejection: First Solar Wind Electron, Proton, Alpha Monitor (SWEPAM) results from the Advanced Composition Explorer SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID ABUNDANCE AB This paper reports the first scientific results from the Solar Wind Electron Proton Alpha Monitor (SWEPAM) instrument on board the Advanced Composition Explorer (ACE) spacecraft. We analyzed a coronal mass ejection (CME) observed in the solar wind using data from early February, 1998. This event displayed several of the common signatures of CMEs, such as counterstreaming halo electrons and depressed ion and electron temperatures, as well as some unusual features. During a portion of the CME traversal, SWEPAM measured a very large helium to proton abundance ratio. Other heavy ions, with a set of ionization states consistent with normal (1-2 x 10(6) IC) coronal temperatures, were proportionately enhanced at this time. These observations suggest a source for at least some of the CME material, where heavy ions are initially concentrated relative to hydrogen and then accelerated up into the solar wind, independent of their mass and first ionization potential. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Scibernet Inc, San Diego, CA 92121 USA. NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP McComas, DJ (reprint author), Univ Calif Los Alamos Natl Lab, D466, Los Alamos, NM 87545 USA. NR 14 TC 19 Z9 19 U1 1 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD DEC 1 PY 1998 VL 25 IS 23 BP 4289 EP 4292 DI 10.1029/1998GL900174 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 143XG UT WOS:000077282400013 ER PT J AU Horbury, TS Lucek, EA Balogh, A McComas, DJ AF Horbury, TS Lucek, EA Balogh, A McComas, DJ TI Wave power dropouts associated with radial field intervals in high speed solar wind SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID HIGH HELIOGRAPHIC LATITUDES; ULYSSES OBSERVATIONS; MAGNETIC-FIELD; PLASMA AB Examination of 770 days of heliospheric magnetic field data recorded within polar solar wind by the Ulysses spacecraft revealed a number of occasions when the wave power decreased by more than an order of magnitude for several hours. These power dropouts were found to be associated with intervals when the magnetic field was closely aligned with the radial direction. A case by case study showed that there was no obvious signature in bulk plasma parameters. A statistical study of 24 intervals when the field was close to radial for at least 6 hours shelved that the wave power in those intervals was significantly lower than that outside. There were no significant power changes when the field lay close to either the Parker spiral or an arbitrary direction. Although they are likely to be of solar origin, the exact source for these events is not clear. C1 Imperial Coll, Blackett Lab, London SW7 2BZ, England. Univ Calif Los Alamos Natl Lab, Los Alamos, NM USA. RP Horbury, TS (reprint author), Univ London Queen Mary & Westfield Coll, Sch Math Sci, Mile End Rd, London E1 4NS, England. NR 14 TC 2 Z9 2 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD DEC 1 PY 1998 VL 25 IS 23 BP 4297 EP 4300 DI 10.1029/1998GL900172 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 143XG UT WOS:000077282400015 ER PT J AU Kim, J Miller, NL Oh, JH Chung, JS Rha, D AF Kim, J Miller, NL Oh, JH Chung, JS Rha, D TI Eastern Asian hydrometeorology simulation using the Regional Climate System Model SO GLOBAL AND PLANETARY CHANGE LA English DT Article; Proceedings Paper CT Project for Intercomparison of Landsurface Parameterization Schemes Workshop (PILPS) CY JUN, 1997 CL MELBOURNE, AUSTRALIA DE regional climate system model; coupled atmosphere-land surface model; East Asian hydroclimate; sustainability ID WESTERN UNITED-STATES; SOIL-WATER; PARAMETERIZATION SCHEMES; CLOUD MODEL; LAND; PRECIPITATION; SENSITIVITY; MOISTURE; LAYER; EVAPOTRANSPIRATION AB We present the hydrometeorology of eastern Asia during April 1995 simulated by the Regional Climate System Model. The amount and location of simulated monthly precipitation agrees well with observations. Soil water content variation was closely correlated with precipitation. Land-surface evaporation and the surface energy budget were strongly controlled by soil moisture content. A sensitivity test with reduced initial soil moisture content suggested that near-surface soil moisture spins up quickly after heavy precipitation events. However, variations in the initial soil moisture field may alter details of the simulated precipitation which can introduce further complexity in climate simulations. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Korean Meteorol Adm, Meteorol Res Inst, Seoul, South Korea. RP Kim, J (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, 1 Cyclotron Rd, Berkeley, CA 94720 USA. EM Jinwon_Kim@LBL.gov; nlmiller@LBL.gov; jho@iris.metri.re.kr; cjs@iris.metri.re.kr; dkrha@iris.metri.re.kr NR 50 TC 9 Z9 10 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-8181 J9 GLOBAL PLANET CHANGE JI Glob. Planet. Change PD DEC PY 1998 VL 19 IS 1-4 BP 225 EP 240 DI 10.1016/S0921-8181(98)00049-6 PG 16 WC Geography, Physical; Geosciences, Multidisciplinary SC Physical Geography; Geology GA 139GF UT WOS:000077019100013 ER PT J AU Polcher, J McAvaney, B Viterbo, P Gaertner, MA Hahmann, A Mahfouf, JF Noilhan, J Phillips, T Pitman, A Schlosser, CA Schulz, JP Timbal, B Verseghy, D Xue, Y AF Polcher, J McAvaney, B Viterbo, P Gaertner, MA Hahmann, A Mahfouf, JF Noilhan, J Phillips, T Pitman, A Schlosser, CA Schulz, JP Timbal, B Verseghy, D Xue, Y TI A proposal for a general interface between land surface schemes and general circulation models SO GLOBAL AND PLANETARY CHANGE LA English DT Article; Proceedings Paper CT Project for Intercomparison of Landsurface Parameterization Schemes Workshop (PILPS) CY JUN, 1997 CL MELBOURNE, AUSTRALIA DE PILPS; land surface schemes; general circulation models; coupling land surface schemes ID FRANCE CLIMATE MODEL; PARAMETERIZATIONS; VALIDATION; PROJECT AB The aim of this paper is to propose a general interface for coupling general circulation models (GCMs) to land surface schemes (LSS) in order to achieve a plug compatibility between these complex models. As surface parameterizations include more processes, they have moved from being subroutines of GCMs to independent schemes which can also be applied for other purposes. This evolution has raised the problem within climate modeling groups of coupling these schemes to GCMs in a simple and flexible way. As LSS reaches a larger independence, a general interface is needed to enable exchange within the community. This paper discusses the tasks LSS have to fulfill when coupled to a GCM after a review of the current state of the art and the likely future evolutions of both components. The numerical schemes used for the processes which couple the land surfaces to the atmosphere are reviewed to ensure that the interface can be applied to all LSS and GCMs after only minor changes. (C) 1998 Elsevier Science B.V. All rights reserved. C1 CNRS, Meteorol Dynam Lab, F-75252 Paris 05, France. Bur Meteorol Res Ctr, Melbourne, Vic, Australia. European Ctr Medium Range Weather Forecasts, Reading RG2 9AX, Berks, England. Univ Complutense, E-28040 Madrid, Spain. Univ Arizona, Tucson, AZ USA. Meteo France, CNRM, Toulouse, France. LLNL, Program Climate Model Diagnosis & Intercompar, Livermore, CA USA. Macquarie Univ, Sydney, NSW 2109, Australia. Ctr Ocean Land Atmosphere Studies, Calverton, MD USA. Max Planck Inst Meteorol, Hamburg, Germany. Canadian Climate Ctr, Downsview, ON, Canada. Univ Maryland, College Pk, MD 20742 USA. RP Polcher, J (reprint author), CNRS, Meteorol Dynam Lab, Tour 25,5 Eme Etage,BP 99,4 Pl Jussieu, F-75252 Paris 05, France. RI Viterbo, Pedro/B-7184-2008; Pitman, Andrew/A-7353-2011; Hahmann, Andrea/B-7541-2015 OI Viterbo, Pedro/0000-0001-6587-3062; Pitman, Andrew/0000-0003-0604-3274; Hahmann, Andrea/0000-0001-8785-3492 NR 24 TC 36 Z9 38 U1 2 U2 11 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-8181 J9 GLOBAL PLANET CHANGE JI Glob. Planet. Change PD DEC PY 1998 VL 19 IS 1-4 BP 261 EP 276 DI 10.1016/S0921-8181(98)00052-6 PG 16 WC Geography, Physical; Geosciences, Multidisciplinary SC Physical Geography; Geology GA 139GF UT WOS:000077019100016 ER PT J AU Geist, DR Joy, MC Lee, DR Gonser, T AF Geist, DR Joy, MC Lee, DR Gonser, T TI A method for installing piezometers in large cobble bed rivers SO GROUND WATER MONITORING AND REMEDIATION LA English DT Article AB An impact drive point method is described for emplacing piezometers in a cobble river bottom where this has previously been difficult without the use of drilling rigs. To force the drive point piezometers through cobble. the vibrational impact of an air-powered hammer was carried directly to the drive point by the use of an internal drive rod. After insertion to depth, the drive rod was removed from the lower portion of the piezometer and a standpipe was added to extend the piezometer above the river level. Piezometers installed in this way have permitted water quality analysis and dynamic measurement of vertical potentials in cobble sediments ranging in size from 2.5 to > 30 cm and the method has been successfully used in the Columbia River. USA, and Toss River, Switzerland. This innovative method provides information on the hydrodynamics of pore water in highly permeable. cobble deposits that are common in high-energy river and lake bottoms. Piezometers installed using the internal drive rod method facilitate the assessment of the temporal and spatial dynamics of recharge and discharge at the ground water/surface water interface and analyses of the ecological connectivity between the hyporheic zone and surface water of rivers and streams. This information will lead to improved management decisions related to our nation's ground water and surface water supplies. C1 Pacific NW Lab, Richland, WA 99352 USA. RP Geist, DR (reprint author), Oregon State Univ, Corvallis, OR 97331 USA. NR 15 TC 13 Z9 13 U1 0 U2 4 PU GROUND WATER PUBLISHING CO PI WESTERVILLE PA 601 DEMPSEY RD, WESTERVILLE, OH 43081 USA SN 1069-3629 J9 GROUND WATER MONIT R JI Ground Water Monit. Remediat. PD WIN PY 1998 VL 18 IS 1 BP 78 EP 82 DI 10.1111/j.1745-6592.1998.tb00604.x PG 5 WC Water Resources SC Water Resources GA YZ586 UT WOS:000072268900007 ER PT J AU Sorensen, SA Low, JO AF Sorensen, SA Low, JO TI Siting criteria based on the prevention of deterministic effects from plutonium inhalation exposures SO HEALTH PHYSICS LA English DT Article DE plutonium; inhalation; dose equivalent, effective; accidents, nuclear AB Siting criteria are established by regulatory authorities to evaluate potential accident scenarios associated with proposed nuclear facilities. The 0.25 Sv (25 rem) siting criteria adopted in the United States has been historically based on the prevention of deterministic effects from acute, whole-body exposures. The Department of Energy has extended the applicability of this criterion to radionuclides that deliver chronic, organ-specific irradiation through the specification of a 0.25 Sv (25 rem) committed effective dose equivalent siting criterion, A methodology is developed to determine siting criteria based on the prevention of deterministic effects from inhalation intakes of radionuclides which deliver chronic, organ-specific irradiation. Revised siting criteria, expressed in terms of committed effective dose equivalent, are proposed for nuclear facilities that handle primarily plutonium compounds, The analysis determined that a siting criterion of 1.2 Sv (120 rem) committed effective dose equivalent for inhalation exposures to weapons-grade plutonium meets the historical goal of preventing deterministic effects during a facility accident scenario, The criterion also meets the Nuclear Regulatory Commission and Department of Energy Nuclear Safety Goals provided that the frequency of the accident is sufficiently low. C1 Enterprise Advisory Serv Inc, Albuquerque, NM 87106 USA. US Dept Energy, Albuquerque Operat Off, Albuquerque, NM 87185 USA. NR 14 TC 0 Z9 0 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0017-9078 EI 1538-5159 J9 HEALTH PHYS JI Health Phys. PD DEC PY 1998 VL 75 IS 6 BP 614 EP 618 DI 10.1097/00004032-199812000-00005 PG 5 WC Environmental Sciences; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 140XR UT WOS:000077115400012 PM 9827508 ER PT J AU Bogen, KT AF Bogen, KT TI Mechanistic model predicts a U-shaped relation of radon exposure to lung cancer risk reflected in combined occupational and US residential data SO HUMAN & EXPERIMENTAL TOXICOLOGY LA English DT Article DE alpha; cytotoxicity; dose-response models; epidemiology; hormesis; multistage; mutation; radiation ID ALPHA-PARTICLES; STATES; COUNTIES; MINERS AB A mechanistically based cytodynamic two-stage (CD2) cancer model was shown recently to predict both ecologic US county data and underground-miner data on lung-cancer mortality (LCM) vs radon concentration, indicating biological plausibility of the apparent negative dose-response relation exhibited by the ecologic data.(6) To further investigate this hypothesis, the CD2 model was fitted to combine age-specific LCM data vs estimated radon-exposure in white females of age 40+ years in 2821 US counties during 1950-1954 using new estimates of county-specific mean residential radon exposure, and in five cohorts of underground nonsmoking miners. The negative association of radon levels and corresponding county-level LCM rates apparent in women dying in 1950-1954 (11% of whom never smoked) was also apparent in women of age 60+ years (5% of whom never smoked). The CD2 fit obtained to the combined residential and occupational data was found to predict the combined data using biologically plausible parameter values, and also to predict inverse dose-rate effects exhibited in nonsmoking miner data to which the CD2 model was not fit. These results are consistent with the hypothesis that residential radon exposure has a nonlinear U-shaped relation to LCM risk, and that current linear extrapolation models substantially overestimate such risk. C1 Univ Calif Lawrence Livermore Natl Lab, Hlth & Ecol Assessment Div, Livermore, CA 94550 USA. RP Bogen, KT (reprint author), Univ Calif Lawrence Livermore Natl Lab, Hlth & Ecol Assessment Div, Livermore, CA 94550 USA. NR 31 TC 15 Z9 17 U1 0 U2 0 PU STOCKTON PRESS PI BASINGSTOKE PA HOUNDMILLS, BASINGSTOKE RG21 6XS, HAMPSHIRE, ENGLAND SN 0144-5952 J9 HUM EXP TOXICOL JI Hum. Exp. Toxicol. PD DEC PY 1998 VL 17 IS 12 BP 691 EP 696 DI 10.1191/096032798678908161 PG 6 WC Toxicology SC Toxicology GA 160BP UT WOS:000078210700007 PM 9988374 ER PT J AU Bogen, KT AF Bogen, KT TI Comments on papers by Andersen and Conolly and by Downs and Frankowski SO HUMAN & EXPERIMENTAL TOXICOLOGY LA English DT Editorial Material DE diethylnitrosamine; dioxin; dose; hormesis; response; U-shape ID LUNG-CANCER; RADON; RATS; FOCI C1 Univ Calif Lawrence Livermore Natl Lab, Hlth & Ecol Assessment Div, Livermore, CA 94550 USA. RP Bogen, KT (reprint author), Univ Calif Lawrence Livermore Natl Lab, Hlth & Ecol Assessment Div, Livermore, CA 94550 USA. NR 10 TC 0 Z9 0 U1 0 U2 0 PU STOCKTON PRESS PI BASINGSTOKE PA HOUNDMILLS, BASINGSTOKE RG21 6XS, HAMPSHIRE, ENGLAND SN 0144-5952 J9 HUM EXP TOXICOL JI Hum. Exp. Toxicol. PD DEC PY 1998 VL 17 IS 12 BP 711 EP 712 DI 10.1191/096032798678908152 PG 2 WC Toxicology SC Toxicology GA 160BP UT WOS:000078210700013 ER PT J AU Bogen, KT AF Bogen, KT TI Response to reviewer comments SO HUMAN & EXPERIMENTAL TOXICOLOGY LA English DT Editorial Material ID RESIDENTIAL RADON; LUNG-CANCER; EXPOSURE; MODEL C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Bogen, KT (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 14 TC 0 Z9 0 U1 0 U2 0 PU STOCKTON PRESS PI BASINGSTOKE PA HOUNDMILLS, BASINGSTOKE RG21 6XS, HAMPSHIRE, ENGLAND SN 0144-5952 J9 HUM EXP TOXICOL JI Hum. Exp. Toxicol. PD DEC PY 1998 VL 17 IS 12 BP 716 EP 718 DI 10.1191/096032798678908189 PG 3 WC Toxicology SC Toxicology GA 160BP UT WOS:000078210700017 ER PT J AU Kennel, SJ Lankford, PK Foote, LJ Davis, IA AF Kennel, SJ Lankford, PK Foote, LJ Davis, IA TI Monoclonal antibody to rat CD63 detects different molecular forms in rat tissue SO HYBRIDOMA LA English DT Article ID ANTIGEN ME491; CELLS; ACTIVATION; EXPRESSION; SUPERFAMILY; INTEGRINS; GROWTH; FAMILY; LINK; CD81 AB From mice immunized with rat endothelial cell membranes, we isolated several hybridomas secreting monoclonal antibodies (MAbs) to a 45-kDa glycoprotein expressed on the surface of cultured cells, One of these antibodies, 523-14A, was purified and used for immunoaffinity chromatography, Western blotting, and immunohistochemistry, The glycoprotein containing the antigen for MAb 523-14A, gp45, was isolated from rat lung endothelial cell membranes using wheat germ agglutinin and antibody affinity chromatography sequentially. Mass spectrometry of tryptic peptides from gel purified bands identified gp45 as rat CD63, a member of the transmembrane-4 superfamily, Western blot analyses of tissues from F344 rats showed that kidney, spleen, uterus, and ovaries expressed CD63 at high levels. Thymus, salivary gland, testicles, intestines, pancreas, and adrenals expressed lower amounts. Tissue cell types expressing CD63 were also examined and the results showed that, in addition to the expected expression on lymphoid cells, CD63 was expressed on many epithelial and muscle cells as well. The mobility of CD63 on SDS-PAGE varied widely, indicative of molecular masses ranging from 45 kDa in some tissues to nearly 60 kDa in others. C1 Oak Ridge Natl Lab, Div Life Sci, Oak Ridge, TN 37831 USA. RP Kennel, SJ (reprint author), Oak Ridge Natl Lab, Div Life Sci, Bldg 4500S MS-6101, Oak Ridge, TN 37831 USA. NR 28 TC 6 Z9 6 U1 0 U2 0 PU MARY ANN LIEBERT INC PUBL PI LARCHMONT PA 2 MADISON AVENUE, LARCHMONT, NY 10538 USA SN 0272-457X J9 HYBRIDOMA JI Hybridoma PD DEC PY 1998 VL 17 IS 6 BP 509 EP 515 DI 10.1089/hyb.1998.17.509 PG 7 WC Biochemical Research Methods; Biotechnology & Applied Microbiology; Immunology SC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology; Immunology GA 153YN UT WOS:000077861300002 PM 9890706 ER PT J AU Feddema, JT Simon, RW AF Feddema, JT Simon, RW TI Visual servoing and CAD-driven microassembly SO IEEE ROBOTICS & AUTOMATION MAGAZINE LA English DT Article DE visual servoing; micro-assembly; micro-manipulation; MEMS; LIGA AB The authors describe current research and development on a robotic visual servoing system for assembly of LIGA (Lithography Galvonoforming Abforming) parts. The workcell consists of an AMTI robot, precision stage, long working distance microscope, and LIGA fabricated tweezers for picking up the parts. Fourier optics methods are used to generate synthetic microscope images from CAD drawings. These synthetic images are used off-line to test image processing routines under varying magnifications and depths of field. They also provide reference image features which are used to visually servo the part to the desired position. Currently, we can visually servo a 100 micron outside diameter LIGA gear to a desired x,y reference position as determined from a synthetic image of the gear. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Feddema, JT (reprint author), Sandia Natl Labs, POB 5800,MS 1003, Albuquerque, NM 87185 USA. NR 14 TC 21 Z9 24 U1 0 U2 4 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1070-9932 J9 IEEE ROBOT AUTOM MAG JI IEEE Robot. Autom. Mag. PD DEC PY 1998 VL 5 IS 4 BP 18 EP 24 DI 10.1109/100.740460 PG 7 WC Automation & Control Systems; Robotics SC Automation & Control Systems; Robotics GA 159AM UT WOS:000078149700005 ER PT J AU Picraux, ST McWhorter, PJ AF Picraux, ST McWhorter, PJ TI The broad sweep of integrated microsystems SO IEEE SPECTRUM LA English DT Article ID SYSTEMS C1 Sandia Natl Labs, Phys & Chem Sci Ctr, Albuquerque, NM 87185 USA. Sandia Natl Labs, Microsyst Sci Technol & Components Ctr, Albuquerque, NM 87185 USA. RP Picraux, ST (reprint author), Sandia Natl Labs, Phys & Chem Sci Ctr, POB 5800, Albuquerque, NM 87185 USA. EM picraux@sandia.gov; mcwhorpj@sandia.gov NR 16 TC 13 Z9 13 U1 0 U2 4 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9235 J9 IEEE SPECTRUM JI IEEE Spectr. PD DEC PY 1998 VL 35 IS 12 BP 24 EP 33 DI 10.1109/6.736447 PG 10 WC Engineering, Electrical & Electronic SC Engineering GA 143MB UT WOS:000077258500016 ER PT J AU Wordelman, CJ Kwan, TJT Snell, CM AF Wordelman, CJ Kwan, TJT Snell, CM TI Comparison of statistical enhancement methods for Monte Carlo semiconductor simulation SO IEEE TRANSACTIONS ON COMPUTER-AIDED DESIGN OF INTEGRATED CIRCUITS AND SYSTEMS LA English DT Article DE Monte Carlo; statistical enhancement; variance reduction ID ELECTRON-TRANSPORT; BAND-STRUCTURE; DEVICES; IONIZATION; SILICON AB Three methods of variable-weight statistical enhancement for Monte Carte semiconductor device simulation are compared, The stead-state statistical errors and figures of merit for implementations of the multicomb, cloning-rouletting, and splitting-gathering enhancement methods are obtained for bulk silicon simulations, The results indicate that all methods enhance the high-energy distribution tail with comparable accuracy, but that the splitting-gathering method achieves a lower error at low energies bg automatically preserving a peak in the bin populations at the peak of the particle energy distribution. C1 Univ Illinois, Dept Elect & Comp Engn, Urbana, IL 61801 USA. Univ Calif Los Alamos Natl Lab, Plasma Phys Applicat Grp, Los Alamos, NM 87544 USA. Univ Calif Los Alamos Natl Lab, Transport Methods Grp, Los Alamos, NM 87544 USA. RP Wordelman, CJ (reprint author), Univ Illinois, Dept Elect & Comp Engn, 1406 W Green St, Urbana, IL 61801 USA. NR 18 TC 14 Z9 14 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0278-0070 J9 IEEE T COMPUT AID D JI IEEE Trans. Comput-Aided Des. Integr. Circuits Syst. PD DEC PY 1998 VL 17 IS 12 BP 1230 EP 1235 DI 10.1109/43.736562 PG 6 WC Computer Science, Hardware & Architecture; Computer Science, Interdisciplinary Applications; Engineering, Electrical & Electronic SC Computer Science; Engineering GA 153NE UT WOS:000077838500002 ER PT J AU Pillay, P Levin, V Otaduy, P Kueck, J AF Pillay, P Levin, V Otaduy, P Kueck, J TI In-situ induction motor efficiency determination using the genetic algorithm SO IEEE TRANSACTIONS ON ENERGY CONVERSION LA English DT Article AB Numerous methods exist for determining the efficiency of induction motors. Many of them require a no-load test, which is not possible for in-situ determination. The evaluation of motor efficiency based on the motor's nameplate or manufacturer's data, on the other hand, in many cases cannot ensure a fair assessment of induction motors employed in the plant. An extensive survey of techniques for efficiency measurement is given. A new method is proposed for in-situ induction motor efficiency determination, based on the genetic algorithm. Results are compared with torque-gauge results. C1 Clarkson Univ, Dept Elect & Comp Engn, Potsdam, NY 13699 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Pillay, P (reprint author), Clarkson Univ, Dept Elect & Comp Engn, Potsdam, NY 13699 USA. NR 14 TC 28 Z9 30 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0885-8969 J9 IEEE T ENERGY CONVER JI IEEE Trans. Energy Convers. PD DEC PY 1998 VL 13 IS 4 BP 326 EP 333 DI 10.1109/60.736318 PG 8 WC Energy & Fuels; Engineering, Electrical & Electronic SC Energy & Fuels; Engineering GA 142XG UT WOS:000077225300004 ER PT J AU Simon, J Saffer, S Sherman, F Kim, CJ AF Simon, J Saffer, S Sherman, F Kim, CJ TI Lateral polysilicon microrelays with a mercury microdrop contact SO IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS LA English DT Article DE cantilever; comb drive; electrostatic; mercury; microrelay AB We present two designs for electrostatically actuated poll silicon relays with a stationary mercury microdrop contact: a large displacement cantilever design and a comb-drive design, both fabricated using the multiuser microelectromechanical systems process of MCNC, Research Triangle Park, NC. Microscale mercury relays combine the high density and batch fabrication of a microscale device with the quality and reliability of a mercury contact, Contact resistance of the devices were found to be similar to 1 k Omega in air with no attempt made to reduce the oxidation of the polysilicon and mercury surfaces. The devices can switch currents over 10 mA, Switching results are presented. The cantilever device is based on a curved electrode design, providing both relatively large force and large displacement of the tip, which contacts the mercury for switching. Nonlinear modeling of the beam movement is also provided. The comb-drive device has the usual double-folded beam design, but has a mercury drop near its center. Fabrication of 10-mu m diameter mercury drops as the last step of the processing sequence is also discussed. C1 Univ Calif Los Angeles, Dept Aerosp & Mech Engn, Livermore, CA 90095 USA. RP Simon, J (reprint author), Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. EM cjkim@seas.ucla.edu RI Kim, Chang-Jin/F-6730-2011 NR 19 TC 17 Z9 17 U1 0 U2 4 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 0278-0046 EI 1557-9948 J9 IEEE T IND ELECTRON JI IEEE Trans. Ind. Electron. PD DEC PY 1998 VL 45 IS 6 BP 854 EP 860 DI 10.1109/41.735328 PG 7 WC Automation & Control Systems; Engineering, Electrical & Electronic; Instruments & Instrumentation SC Automation & Control Systems; Engineering; Instruments & Instrumentation GA 144EA UT WOS:000077299800003 ER PT J AU Zimmerman, RK AF Zimmerman, RK TI Crossed dipoles fed with a turnstile network SO IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES LA English DT Article DE antenna components; antenna feeds; circular polarization AB A "turnstile network" is introduced which may be conveniently used for circular polarization synthesis. The network, outfitted with proper phasing stubs, forms a balanced quadrature hybrid; for an antenna with less than a perfect reflection coefficient, the reflected power will appear at an isolated port, which may be terminated, resulting in good polarization properties coupled with good input voltage standing wave ratio. A crossed-dipole array is used as a test-bed to demonstrate the turnstile network. C1 Arecibo Observ, Arecibo, PR 00614 USA. RP Zimmerman, RK (reprint author), Univ Calif Los Alamos Natl Lab, LANSCE 5, MS H827, Los Alamos, NM 87545 USA. NR 5 TC 5 Z9 5 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9480 J9 IEEE T MICROW THEORY JI IEEE Trans. Microw. Theory Tech. PD DEC PY 1998 VL 46 IS 12 BP 2151 EP 2156 DI 10.1109/22.739298 PN 1 PG 6 WC Engineering, Electrical & Electronic SC Engineering GA 158CP UT WOS:000078098700025 ER PT J AU Schwank, JR AF Schwank, JR TI 1998 IEEE Nuclear and Space Radiation Effects Conference SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Editorial Material C1 Sandia Natl Labs, Livermore, CA 94550 USA. RP Schwank, JR (reprint author), Sandia Natl Labs, Livermore, CA 94550 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD DEC PY 1998 VL 45 IS 6 BP 2327 EP 2328 PN 1 PG 2 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 149UM UT WOS:000077624200001 ER PT J AU Sexton, FW AF Sexton, FW TI 1998 Special NSREC issue of the IEEE Transactions on Nuclear Science - Guest editor's comments SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Editorial Material C1 Sandia Natl Labs, Livermore, CA 94550 USA. RP Sexton, FW (reprint author), Sandia Natl Labs, Livermore, CA 94550 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD DEC PY 1998 VL 45 IS 6 BP 2334 EP 2334 PN 1 PG 1 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 149UM UT WOS:000077624200003 ER PT J AU Witczak, SC Lacoe, RC Mayer, DC Fleetwood, DM Schrimpf, RD Galloway, KF AF Witczak, SC Lacoe, RC Mayer, DC Fleetwood, DM Schrimpf, RD Galloway, KF TI Space charge limited degradation of bipolar oxides at low electric fields SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 35th IEEE International Nuclear and Space Radiation Effects Conference (NSREC) CY JUL 20-24, 1998 CL NEWPORT BEACH, CALIFORNIA SP IEEE/NPSS Radiat Effects Comm ID TOTAL-DOSE RESPONSE; INTERFACE-STATE GENERATION; SHALLOW-ACCEPTOR IMPURITIES; SINGLE-CRYSTAL SILICON; GROUP-III ACCEPTORS; SI-SIO2 INTERFACE; HYDROGEN PASSIVATION; TRAPPED HOLES; INTEGRATED-CIRCUITS; IONIZING-RADIATION AB P-type MOS capacitors fabricated in two bipolar processes were examined for ionizing radiation-induced threshold voltage shifts as a function of total dose, dose rate, temperature and bias. Hydrogen passivation of acceptor impurities near the Si surface was observed through decreases in the Si capacitance. The reduction in net electrically active dopants shifts the threshold voltage negative with total dose. The relative contribution of dopant passivation to the radiation-induced threshold voltage shift is most significant for irradiations performed under zero bias above 100 degrees C. For zero bias, dopant passivation and densities of radiation-induced interface traps and net positive oxide trapped charge all exhibit true dose rate and time dependent effects. A positive gate bias during irradiation eliminates the dose rate dependence. High dose rate irradiation at elevated temperatures enhances oxide degradation while simultaneously accelerating the annealing of damage. The enhancement in interface trap formation is greater than that of net positive oxide trapped charge and occurs over a greater range of temperatures. The temperature dependence of dopant passivation indicates that hydrogen transport through the oxides is accelerated with temperature. These results strongly suggest that metastably trapped charge in the oxide bulk reduces high dose rate degradation at room temperature by inhibiting the transport of holes and H+ ions. C1 Aerospace Corp, Inst Electron Technol, Los Angeles, CA 90009 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. Vanderbilt Univ, Dept Elect & Comp Sci, Nashville, TN 37235 USA. RP Witczak, SC (reprint author), Aerospace Corp, Inst Electron Technol, POB 92957, Los Angeles, CA 90009 USA. RI Schrimpf, Ronald/L-5549-2013 OI Schrimpf, Ronald/0000-0001-7419-2701 NR 139 TC 77 Z9 98 U1 3 U2 15 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD DEC PY 1998 VL 45 IS 6 BP 2339 EP 2351 DI 10.1109/23.736453 PN 1 PG 13 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 149UM UT WOS:000077624200005 ER PT J AU Graves, RJ Cirba, CR Schrimpf, RD Milanowski, RJ Michez, A Fleetwood, DM Witczak, SC Saigne, F AF Graves, RJ Cirba, CR Schrimpf, RD Milanowski, RJ Michez, A Fleetwood, DM Witczak, SC Saigne, F TI Modeling low-dose-rate effects in irradiated bipolar-base oxides SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 35th IEEE International Nuclear and Space Radiation Effects Conference (NSREC) CY JUL 20-24, 1998 CL NEWPORT BEACH, CALIFORNIA SP IEEE/NPSS Radiat Effects Comm ID GAIN DEGRADATION; IONIZING-RADIATION; TRAPPED HOLES; TRANSISTORS; DEPENDENCE; SUBSTRATE; SILICON; ENERGY; CHARGE; BJTS AB A physical model is developed to quantify the contribution of oxide-trapped charge to enhanced low-dose-rate gain degradation in bipolar junction transistors. Multiple-trapping simulations show that space charge limited transport is partially responsible for low-dose-rate enhancement. At low dose rates, more holes are trapped near the silicon-oxide interface than at high dose rates, resulting in larger midgap voltage shifts. The additional trapped charge near the interface causes an exponential increase in excess base current and a resultant decrease in current gain for some NPN bipolar technologies. Space charge effects also may be responsible for differences in interface trap formation at low and high dose rates. C1 SILVACO Int, Scottsdale, AZ 85251 USA. Vanderbilt Univ, ECE Dept, Nashville, TN 37235 USA. Univ Montpellier 2, F-34095 Montpellier, France. Sandia Natl Labs, Albuquerque, NM 87185 USA. Aerospace Corp, Los Angeles, CA 90009 USA. RP Graves, RJ (reprint author), SILVACO Int, Scottsdale, AZ 85251 USA. RI Schrimpf, Ronald/L-5549-2013 OI Schrimpf, Ronald/0000-0001-7419-2701 NR 33 TC 33 Z9 50 U1 1 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD DEC PY 1998 VL 45 IS 6 BP 2352 EP 2360 DI 10.1109/23.736454 PN 1 PG 9 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 149UM UT WOS:000077624200006 ER PT J AU Fleetwood, DM Winokur, PS Shaneyfelt, MR Riewe, LC Flament, O Paillet, P Leray, JL AF Fleetwood, DM Winokur, PS Shaneyfelt, MR Riewe, LC Flament, O Paillet, P Leray, JL TI Effects of isochronal annealing and irradiation temperature on radiation-induced trapped charge SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 35th IEEE International Nuclear and Space Radiation Effects Conference (NSREC) CY JUL 20-24, 1998 CL NEWPORT BEACH, CALIFORNIA SP IEEE/NPSS Radiat Effects Comm ID STIMULATED CURRENT MEASUREMENTS; OXIDE-SEMICONDUCTOR DEVICES; BORDER TRAPS; INTERFACE TRAPS; MOS CAPACITORS; TRANSISTORS; HARDNESS; ENERGY AB Radiation-induced trapped charge densities in 45-nm radiation-hardened oxides are estimated via capacitance-voltage (C-V) and thermally stimulated current (TSC) techniques as functions of irradiation and/or isochronal anneal temperature. Reductions in trapped-hole charge were greater for -10 V and 0 V isochronal anneals than for 10 V anneals. This is attributed to enhanced electron-hole dipole pairing during positive-bias anneal. Between 22 degrees C and 125 degrees C, the trapped electron charge increases for 10 V isochronal anneals, and is approximately constant for 0 V and -10 V anneals. Interface-trap charge decreases for 0 V isochronal annealing above 80 degrees C and +/-10 V annealing above 100 degrees C. Elevated temperature irradiation at 10 V shows similar trends to 10 V isochronal anneals. Trapped-hole energy scales derived from C-V measurements for positive or zero bias isochronal anneals are found to be inaccurate, due to the different temperature dependencies of trapped-hole annealing and trapped-electron buildup. Refined estimates of trapped-hole attempt-to-escape frequency are obtained via TSC. Isochronal annealing and elevated temperature irradiation techniques generally cannot be used for hardness assurance testing unless the results are "calibrated" to the low-rate irradiation or long-term annealing response for a given technology. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. CEA, Ctr Etud Bruyeres Le Chatel, F-91680 Bruyeres Le Chatel, France. RP Fleetwood, DM (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 43 TC 31 Z9 31 U1 2 U2 7 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD DEC PY 1998 VL 45 IS 6 BP 2366 EP 2374 DI 10.1109/23.736456 PN 1 PG 9 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 149UM UT WOS:000077624200008 ER PT J AU Vanheusden, K Fleetwood, DM Shaneyfelt, MR Draper, BL Schwank, JR AF Vanheusden, K Fleetwood, DM Shaneyfelt, MR Draper, BL Schwank, JR TI The effects of irradiation and proton implantation on the density of mobile protons in SiO2 thin films SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 35th IEEE International Nuclear and Space Radiation Effects Conference (NSREC) CY JUL 20-24, 1998 CL NEWPORT BEACH, CALIFORNIA SP IEEE/NPSS Radiat Effects Comm ID MEMORY DEVICE; CENTERS; DEFECTS; WAFERS; CHARGE AB The radiation response of mobile protons introduced into thermal oxides capped with poly-Si is investigated. Total dose irradiation data show that the cross section for capture of radiation-induced electrons by mobile protons is two orders of magnitude smaller than for electron capture by trapped holes. A consistent model is proposed to explain the weak temperature dependence of the capture process observed in this study as opposed to the strong increase in proton neutralization with increasing temperature observed in an earlier UV exposure study. In contrast with the behavior of SOI material, no post-irradiation trapping of mobile protons could be observed in the thermal SiO2 layer of the Si/SiO2/Si structures studied in this work. In the second part of this work it is shown that, unlike the effect of annealing in a hydrogen containing ambient, proton implantation does not yield a significant number of mobile protons in the buried oxide of Si/SiO2/Si structures. C1 USAF, Res Lab, Space Elect & Protect Branch VSSE, Kirtland AFB, NM 87117 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Vanheusden, K (reprint author), USAF, Res Lab, Space Elect & Protect Branch VSSE, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117 USA. NR 25 TC 9 Z9 9 U1 1 U2 5 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD DEC PY 1998 VL 45 IS 6 BP 2391 EP 2397 DI 10.1109/23.736459 PN 1 PG 7 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 149UM UT WOS:000077624200011 ER PT J AU Dodd, PE Musseau, O Shaneyfelt, MR Sexton, FW D'hose, C Hash, GL Martinez, M Loemker, RA Leray, JL Winokur, PS AF Dodd, PE Musseau, O Shaneyfelt, MR Sexton, FW D'hose, C Hash, GL Martinez, M Loemker, RA Leray, JL Winokur, PS TI Impact of ion energy on single-event upset SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 35th IEEE International Nuclear and Space Radiation Effects Conference (NSREC) CY JUL 20-24, 1998 CL NEWPORT BEACH, CALIFORNIA SP IEEE/NPSS Radiat Effects Comm ID CHARGE COLLECTION; CROSS-SECTIONS; HEAVY-ION; SILICON; SEU; RATES; TRACK AB The impact of ion energy on single-event upset was investigated by irradiating CMOS SRAMs with low and high-energy heavy ions. A variety of CMOS SRAM technologies was studied, with gate lengths ranging from 1 to 0.5 mu m and integration densities from 16 Kbit to 1 Mbit. No significant differences were observed between the low and high-energy single-event upset response. The results are consistent with simulations of heavy-ion track structures that show the central core of the track structures are nearly identical for low and high-energy ions. Three-dimensional simulations confirm that charge collection is similar in the two cases. Standard low energy heavy ion tests are more cost-effective and appear to be sufficient for CMOS technologies down to 0.5 mu m. We discuss implications for deep submicron scaling, multiple-bit upsets, and hardness assurance. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. CEA, DRIF, Bruyeres Le Chatel, France. RP Dodd, PE (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 28 TC 60 Z9 62 U1 0 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD DEC PY 1998 VL 45 IS 6 BP 2483 EP 2491 DI 10.1109/23.736489 PN 1 PG 9 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 149UM UT WOS:000077624200023 ER PT J AU Sexton, FW Fleetwood, DM Shaneyfelt, MR Dodd, PE Hash, GL Schanwald, LP Loemker, RA Krisch, KS Green, ML Weir, BE Silverman, PJ AF Sexton, FW Fleetwood, DM Shaneyfelt, MR Dodd, PE Hash, GL Schanwald, LP Loemker, RA Krisch, KS Green, ML Weir, BE Silverman, PJ TI Precursor ion damage and angular dependence of single event gate rupture in thin oxides SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 35th IEEE International Nuclear and Space Radiation Effects Conference (NSREC) CY JUL 20-24, 1998 CL NEWPORT BEACH, CALIFORNIA SP IEEE/NPSS Radiat Effects Comm ID VERTICAL POWER MOSFETS; N2O AB No correlation was observed between single-event gate rupture (SEGR) and precursor damage by heavy-ion irradiation for 7-nm thermal and nitrided oxides. Precursor ion damage at biases below SEGR threshold for fluence variations over three orders of magnitude had no significant effect on SEGR thresholds. These data support a true single ion model for SEGR. A physical model based on the concept of a conducting pipe is developed that explains the empirical equation for the linear dependence of inverse critical field to rupture with LET. This model also explains the dependence of critical voltage on angle of incidence. As the oxide thickness approaches the diameter of the conducting pipe, the angular dependence of the critical voltage disappears. A model fit to the data suggests a central core diameter of 6 and 8 nm for conducting pipes induced in MOS oxides by Br and Au ions, respectively. The buildup of precursor ion damage in the oxides depends on ion species and bias during irradiation, but is not consistent with the accumulation of total ionizing dose damage. Some 5-nm oxides exhibited the characteristic high leakage current of SEGR; however, most 5-nm devices showed only soft breakdown during heavy ion exposure with electric fields up to 12 MV/cm. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Lucent Technol, Bell Labs, Murray Hill, NJ 07974 USA. RP Sexton, FW (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 20 TC 85 Z9 86 U1 1 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD DEC PY 1998 VL 45 IS 6 BP 2509 EP 2518 DI 10.1109/23.736492 PN 1 PG 10 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 149UM UT WOS:000077624200026 ER PT J AU Schone, H Walsh, DS Sexton, FW Doyle, BL Dodd, PE Aurand, JF Flores, RS Wing, N AF Schone, H Walsh, DS Sexton, FW Doyle, BL Dodd, PE Aurand, JF Flores, RS Wing, N TI Time-resolved ion beam induced charge collection (TRIBICC) in micro-electronics SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 35th IEEE International Nuclear and Space Radiation Effects Conference (NSREC) CY JUL 20-24, 1998 CL NEWPORT BEACH, CALIFORNIA SP IEEE/NPSS Radiat Effects Comm ID TRANSIENTS; DAMAGE AB The entire current transient induced by single 12-MeV Carbon ions was measured at a 5GHz analog bandwidth. A focused ion micro-beam was used to acquire multiple single ion transients at multiple locations of a single CMOS transistor. The current transients reveal clear and discernible contributions of drift and diffusive charge collection. Transients measured for drain and off-drain ion strikes compare well to 3D DAVINCI calculations. The simulations match the drift charge collection measurements within experimental errors. Estimates are presented for the drift assisted funneling charge collection depth. C1 USAF, Res Lab, VSSE, Albuquerque, NM 87117 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Schone, H (reprint author), USAF, Res Lab, VSSE, 3550 Aberdeen Ave, Albuquerque, NM 87117 USA. NR 12 TC 29 Z9 29 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD DEC PY 1998 VL 45 IS 6 BP 2544 EP 2549 DI 10.1109/23.736496 PN 1 PG 6 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 149UM UT WOS:000077624200030 ER PT J AU Shaneyfelt, MR Dodd, PE Draper, BL Flores, RS AF Shaneyfelt, MR Dodd, PE Draper, BL Flores, RS TI Challenges in hardening technologies using shallow-trench isolation SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 35th IEEE International Nuclear and Space Radiation Effects Conference (NSREC) CY JUL 20-24, 1998 CL NEWPORT BEACH, CALIFORNIA SP IEEE/NPSS Radiat Effects Comm ID POLYSILICON GATE; SILICON; CMOS; TRANSISTORS; SIO2 AB Challenges related to radiation hardening CMOS technologies with shallow-trench isolation are explored. It is shown that developing a radiation-hardened CMOS technology with shallow trench isolation is more complex than using a traditional hardened field oxide as the trench insulator. We illustrate the use of device simulations in concert with measurements on test structures to provide detailed physical insight into methods for improving total-dose radiation response. Mechanisms that can limit the total-dose radiation hardness of shallow trench isolation such as high electric fields and ion implantation damage are explored, We demonstrate the successful conversion of a non-radiation hardened technology with LOGOS isolation (Sandia's CMOS6) into a greater than 1 Mrad(SiO2) radiation-hardened shallow-trench isolated technology (Sandia's CMOS6r). C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Shaneyfelt, MR (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 34 TC 151 Z9 158 U1 1 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD DEC PY 1998 VL 45 IS 6 BP 2584 EP 2592 DI 10.1109/23.736501 PN 1 PG 9 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 149UM UT WOS:000077624200035 ER PT J AU Witczak, SC Schrimpf, RD Barnaby, HJ Lacoe, RC Mayer, DC Galloway, KF Pease, RL Fleetwood, DM AF Witczak, SC Schrimpf, RD Barnaby, HJ Lacoe, RC Mayer, DC Galloway, KF Pease, RL Fleetwood, DM TI Moderated degradation enhancement of lateral pnp transistors due to measurement bias SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 35th IEEE International Nuclear and Space Radiation Effects Conference (NSREC) CY JUL 20-24, 1998 CL NEWPORT BEACH, CALIFORNIA SP IEEE/NPSS Radiat Effects Comm ID GAIN DEGRADATION; BIPOLAR AB Enhanced low-dose-rate gain degradation of ADI RF25 lateral pnp transistors is examined as a function of the bias at which the gain is measured. Degradation enhancement at low dose rates diminishes rapidly with increasing measurement bias between the emitter and the base. Device simulations reveal that interface trap charging, field effects from oxide trapped charge and emitter metallization, base series resistance and high-level carrier injection all contribute to this behavior. As a practical consequence, accelerated hardness assurance tests of this device require higher irradiation temperatures or larger design margins for low power applications. C1 Aerospace Corp, Elect Technol Ctr, Los Angeles, CA 90009 USA. Vanderbilt Univ, Dept Elect & Comp Engn, Nashville, TN 37235 USA. RLP Res Inc, Albuquerque, NM 87122 USA. Sandia Natl Labs, Dept 1727, Albuquerque, NM 87185 USA. RP Witczak, SC (reprint author), Aerospace Corp, Elect Technol Ctr, POB 92957, Los Angeles, CA 90009 USA. RI Schrimpf, Ronald/L-5549-2013 OI Schrimpf, Ronald/0000-0001-7419-2701 NR 12 TC 14 Z9 15 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD DEC PY 1998 VL 45 IS 6 BP 2644 EP 2648 DI 10.1109/23.736509 PN 1 PG 5 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 149UM UT WOS:000077624200043 ER PT J AU Shinn, JL Cucinotta, FA Simonsen, LC Wilson, JW Badavi, FF Badhwar, GD Miller, J Zeitlin, C Heilbronn, T Tripathi, RK Clowdsley, MS Heinbockel, JH Xapsos, MA AF Shinn, JL Cucinotta, FA Simonsen, LC Wilson, JW Badavi, FF Badhwar, GD Miller, J Zeitlin, C Heilbronn, T Tripathi, RK Clowdsley, MS Heinbockel, JH Xapsos, MA TI Validation of a comprehensive space radiation transport code SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 35th IEEE International Nuclear and Space Radiation Effects Conference (NSREC) CY JUL 20-24, 1998 CL NEWPORT BEACH, CALIFORNIA SP IEEE/NPSS Radiat Effects Comm ID ACCURATE UNIVERSAL PARAMETERIZATION; GALACTIC COSMIC-RADIATION; ABSORPTION CROSS-SECTIONS; HEAVY-ION FRAGMENTATION; TARGET FRAGMENTATION; ENERGY DEPOSITION; MODEL; SPECTRA; SHUTTLE; COLLISIONS AB The HZETRN code has been developed over the past decade to evaluate the local radiation fields within sensitive materials on spacecraft in the space environment. Most of the more important nuclear and atomic processes are now modeled and evaluation within a complex spacecraft geometry with differing material components, including transition effects across boundaries of dissimilar materials, are included. The atomic/nuclear database and transport procedures have received limited validation in laboratory testing with high energy ion beams.,The codes have been applied in design of the SAGE-III instrument resulting in material changes to control injurious neutron production, in the study of the Space Shuttle single event upsets, and in validation with space measurements (particle telescopes, tissue equivalent. proportional counters, CR-39) on Shuttle and Mir. The present paper reviews the code development and presents recent results in laboratory and space flight validation. C1 NASA, Langley Res Ctr, Hampton, VA 23665 USA. NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA. Christopher Newport Univ, Newport News, VA 23606 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA USA. Hampton Univ, Hampton, VA 23668 USA. Old Dominion Univ, Norfolk, VA USA. USN, Res Lab, Washington, DC 20375 USA. RP Shinn, JL (reprint author), NASA, Langley Res Ctr, Hampton, VA 23665 USA. NR 48 TC 17 Z9 18 U1 0 U2 4 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD DEC PY 1998 VL 45 IS 6 BP 2711 EP 2719 DI 10.1109/23.736519 PN 1 PG 9 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 149UM UT WOS:000077624200052 PM 11542474 ER PT J AU Schanwald, LP Schwank, JR Sniegowski, JJ Walsh, DS Smith, NF Peterson, KA Shaneyfelt, MR Winokur, PS Smith, JH Doyle, BL AF Schanwald, LP Schwank, JR Sniegowski, JJ Walsh, DS Smith, NF Peterson, KA Shaneyfelt, MR Winokur, PS Smith, JH Doyle, BL TI Radiation effects on surface micromachined comb drives and microengines SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 35th IEEE International Nuclear and Space Radiation Effects Conference (NSREC) CY JUL 20-24, 1998 CL NEWPORT BEACH, CALIFORNIA SP IEEE/NPSS Radiat Effects Comm ID MEMS; ACCELEROMETERS; FRICTION AB Surface micromachined comb drive and microengine fluence thresholds and failure modes were investigated in x-ray, electron, and proton total-dose environments. Very high electron, and proton total-dose environments. Very high fluence levels were necessary to induce motion degradation or lockup for normal device biasing or operation. For the abnormal biasing of ungrounded or partially grounded dice, significantly lower fault thresholds were observed, but still in a medium or high fluence range. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Schanwald, LP (reprint author), Sandia Natl Labs, POB 5800,MS 0972, Albuquerque, NM 87185 USA. NR 16 TC 28 Z9 28 U1 4 U2 5 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD DEC PY 1998 VL 45 IS 6 BP 2789 EP 2798 DI 10.1109/23.736529 PN 1 PG 10 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 149UM UT WOS:000077624200062 ER PT J AU Ritzau, SM Funsten, HO Harper, RW Korde, R AF Ritzau, SM Funsten, HO Harper, RW Korde, R TI Damage induced in 100% internal carrier collection efficiency silicon photodiodes by 10-60 keV ion irradiation SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 35th IEEE International Nuclear and Space Radiation Effects Conference (NSREC) CY JUL 20-24, 1998 CL NEWPORT BEACH, CALIFORNIA SP IEEE/NPSS Radiat Effects Comm AB We measure the change in the response of 100% internal carrier collection efficiency silicon photodiodes having 60 Angstrom SiO2 passivation layers due to the damage induced by bombardment with 10-60 keV ions of H, He, N, Ne, and Ar. We find an initially exponential decrease in responsivity with increasing ion fluence Phi and use this to define a damage constant beta. The correlation of beta with the nuclear stopping power of the incident ion instead of the with the total energy lost to nuclear stopping indicates that damage in a channel lying within the n-type silicon near the Si-SiO2 interface dominates the radiation-induced change in the photodiode response. We use a fluid model of electron transport in the channel to derive a universal curve to describe the damage as a function of ion fluence and to show that the damage constant beta is proportional to the damage cross section. Over the energy range of this study, damage cross sections of N+, Ne+, and Ar+ are 10-100 times that of He+, and similar to 1000 times that of H. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Allied Signal Inc, Los Alamos Off, Los Alamos, NM 87544 USA. Int Radiat Detectors, Unit C, Torrance, CA 90505 USA. RP Ritzau, SM (reprint author), Univ Calif Los Alamos Natl Lab, MS D466, Los Alamos, NM 87545 USA. RI Funsten, Herbert/A-5702-2015 OI Funsten, Herbert/0000-0002-6817-1039 NR 7 TC 8 Z9 8 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD DEC PY 1998 VL 45 IS 6 BP 2820 EP 2825 DI 10.1109/23.736534 PN 1 PG 6 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 149UM UT WOS:000077624200067 ER PT J AU Reutter, BW Gullberg, GT Huesman, RH AF Reutter, BW Gullberg, GT Huesman, RH TI Kinetic parameter estimation from attenuated SPECT projection measurements SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 1997 Medical Imaging Conference CY NOV 13-15, 1997 CL ALBUQUERQUE, NEW MEXICO ID OF-INTEREST EVALUATION; MODEL-BASED ESTIMATION; EMISSION TOMOGRAPHY; COMPUTED-TOMOGRAPHY; RECONSTRUCTION; ALGORITHM AB Conventional analysis of dynamically acquired nuclear medicine data involves fitting kinetic models to time-activity curves generated from regions of interest defined on a temporal sequence of reconstructed images. However, images reconstructed from the inconsistent projections of a time-varying distribution of radiopharmaceutical acquired by a rotating SPECT system can contain artifacts that lead to biases in the estimated kinetic parameters. To overcome this problem we investigated the estimation of kinetic parameters directly from projection data by modeling the data acquisition process. To accomplish this it was necessary to parametrize the spatial and temporal distribution of the radiopharmaceutical within the SPECT field of view. In a simulated transverse slice, kinetic parameters were estimated for simple one compartment models for three myocardial regions of interest, as well as for the liver. Myocardial uptake and washout parameters estimated by conventional analysis of noiseless simulated data had biases ranging between 1-63%. Parameters estimated directly from the noiseless projection data were unbiased as expected, since the model used for fitting was faithful to the simulation. Predicted uncertainties (standard deviations) of the parameters obtained for 500,000 detected events ranged between 2-31% for the myocardial uptake parameters and 2-23% for the myocardial washout parameters. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Funct Imaging, Berkeley, CA 94720 USA. Univ Utah, Dept Radiol, Salt Lake City, UT 84132 USA. RP Reutter, BW (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Funct Imaging, Berkeley, CA 94720 USA. NR 18 TC 41 Z9 41 U1 0 U2 5 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD DEC PY 1998 VL 45 IS 6 BP 3007 EP 3013 DI 10.1109/23.737657 PN 2 PG 7 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 149UQ UT WOS:000077624500004 ER PT J AU Weisenberger, AG Kross, B Majewski, S Wojick, R Bradley, EL Saha, MS AF Weisenberger, AG Kross, B Majewski, S Wojick, R Bradley, EL Saha, MS TI Design features and performance of a CsI(Na) array based gamma camera for small animal gene research SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 1997 Medical Imaging Conference CY NOV 13-15, 1997 CL ALBUQUERQUE, NM ID POSITION-SENSITIVE PMT; ULTRA-HIGH-RESOLUTION; SMALL-FIELD; IODINE-125; DETECTORS; SPECT AB We report on the development and performance of a radiation imaging system based on a 110 mm diameter matrix of 1 mm x 1 mm size CsI(Na) scintillating crystals. This detector system has been optimized for high resolution radiation imaging of the distribution of iodine 125 ((125)I) in a laboratory animal. The radioisotope (125)I is readily available as a label to molecular biology probes that can be used in gene research. The system utilizes the Hamamatsu 5 inch diameter 3292 position sensitive photomultiplier tube (PSPMT) coupled to the CsI(Na) matrix and a custom built high resolution copper-beryllium collimator. A resulting spatial resolution of the order of 1.5 mm FWHM and a sensitivity of 68 cpm/mu Ci were obtained with the copper-beryllium collimator. The detector system is installed on a rotating gantry to obtain multiple projections and is now being used in animal studies. C1 Thomas Jefferson Natl Accelerator Facil, Detector Grp, Newport News, VA 23607 USA. Coll William & Mary, Dept Biol, Williamsburg, VA 23185 USA. Coll William & Mary, Dept Appl Sci, Williamsburg, VA 23185 USA. RP Weisenberger, AG (reprint author), Thomas Jefferson Natl Accelerator Facil, Detector Grp, Newport News, VA 23607 USA. NR 19 TC 26 Z9 27 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD DEC PY 1998 VL 45 IS 6 BP 3053 EP 3058 DI 10.1109/23.737663 PN 2 PG 6 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 149UQ UT WOS:000077624500010 ER PT J AU Beuville, E Cahn, R Cederstrom, B Danielsson, M Hall, A Hasegawa, B Luo, L Lundqvist, M Nygren, D Oltman, E Walton, J AF Beuville, E Cahn, R Cederstrom, B Danielsson, M Hall, A Hasegawa, B Luo, L Lundqvist, M Nygren, D Oltman, E Walton, J TI High resolution X-ray imaging using a silicon strip detector SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 1997 Medical Imaging Conference CY NOV 13-15, 1997 CL ALBUQUERQUE, NEW MEXICO ID DIGITAL MAMMOGRAPHY AB We are presenting the first images and an initial evaluation of a scanned-slot X-ray imaging system based on edge-on silicon strip detectors and high-speed low-noise parallel processing ASICs. We have demonstrated noiseless single photon counting above a minimal threshold of 7.2 keV. Edge scans show negligible cross talk between different channels in the ASIC. The Modulation Transfer Function (MTF) has been measured and found to agree with the ideal MTF for 100 mu m pixel size. The first images are obtained at very low exposures and show the high performance of the system. We also present a way of enhancing the X-ray flux to a slot by using a refractive X-ray lens. We believe this focusing device will significantly enhance the potential for scanned-slot X-ray imaging. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Calif San Francisco, S San Francisco, CA 94080 USA. RP Beuville, E (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. NR 16 TC 37 Z9 39 U1 0 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD DEC PY 1998 VL 45 IS 6 BP 3059 EP 3063 DI 10.1109/23.737664 PN 2 PG 5 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 149UQ UT WOS:000077624500011 ER PT J AU Malluhi, QM Johnston, WE AF Malluhi, QM Johnston, WE TI Coding for high availability of a distributed-parallel storage system SO IEEE TRANSACTIONS ON PARALLEL AND DISTRIBUTED SYSTEMS LA English DT Article DE storage systems; availability; scalability; RAID; high performance; distributed systems; error-correcting codes ID EFFICIENT AB We have developed a distributed parallel storage system that employs the aggregate bandwidth of multiple data servers connected by a high-speed wide-area network to achieve scalability and high data throughput. This paper studies different schemes to enhance the reliability and availability of such network-based distributed storage systems. The general approach of this paper employs "erasure" error-correcting codes that can be used to reconstruct missing information caused by hardware, software, or human faults. The paper describes the approach and develops optimized algorithms for the encoding and decoding operations. Moreover, the paper presents techniques for reducing the communication and computation overhead incurred while reconstructing missing data from the redundant information. These techniques include clustering, multidimensional coding, and the full two-dimensional parity schemes. The paper considers trade-offs between redundancy, fault tolerance, and complexity of error recovery. C1 Jackson State Univ, Dept Comp Sci, Jackson, MS 39217 USA. Ernesto Orlando Lawrence Berkeley Natl Lab, Informat & Comp Sci Div, Berkeley, CA 94720 USA. RP Jackson State Univ, Dept Comp Sci, POB 18839, Jackson, MS 39217 USA. EM qmalluhi@homs.jsums.edu NR 20 TC 12 Z9 12 U1 0 U2 0 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1314 USA SN 1045-9219 EI 1558-2183 J9 IEEE T PARALL DISTR JI IEEE Trans. Parallel Distrib. Syst. PD DEC PY 1998 VL 9 IS 12 BP 1237 EP 1252 DI 10.1109/71.737699 PG 16 WC Computer Science, Theory & Methods; Engineering, Electrical & Electronic SC Computer Science; Engineering GA 150VZ UT WOS:000077687600007 ER PT J AU Chan, C Mizuno, B Wood, BP AF Chan, C Mizuno, B Wood, BP TI Special issue on plasma processing SO IEEE TRANSACTIONS ON PLASMA SCIENCE LA English DT Editorial Material C1 Northeastern Univ, Boston, MA 02115 USA. Matsushita Elect Ind Co Ltd, Moriguchi, Osaka 570, Japan. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Chan, C (reprint author), Northeastern Univ, Boston, MA 02115 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0093-3813 J9 IEEE T PLASMA SCI JI IEEE Trans. Plasma Sci. PD DEC PY 1998 VL 26 IS 6 BP 1590 EP 1591 PG 2 WC Physics, Fluids & Plasmas SC Physics GA 162DF UT WOS:000078329600001 ER PT J AU Cluggish, BP AF Cluggish, BP TI Transport of a cathodic arc plasma in a straight, magnetized duct SO IEEE TRANSACTIONS ON PLASMA SCIENCE LA English DT Article DE cathodic arc; macroparticle filtering; magnetized duct; vacuum arc ID VACUUM-ARC; MACROPARTICLE FILTERS; DEPOSITION; FIELD; BIAS AB Measurements are presented of the transport of a supersonic, cathodic-arc plasma through a straight, magnetized duct. These measurements are compared to previous work on curved ducts, in order to illuminate the effect of duct curvature on the transport. The axial ion flux through the straight duct decays as ions are lost to the walls, This decay is exponential, with a scale length of seven duct radii; this is two to three times longer than in most experiments on curved ducts. The scale length is independent of the magnetic field strength for fields from 5-40 mT. (For this range of magnetic fields, the electron Larmor radius varies from 0.03-0.003 duct radii; while the ion Larmor radius varies from 4-0.5 duct radii.) This differs from previous experiments with curved ducts, where the attenuation length generally increases with magnetic field. Also in contrast to experiments on curved ducts, biasing the duct wall to positive voltages similar to the ion energy produces only a slight decrease in the ion losses to the wall. The observed scale length for ion loss and its independence from the magnetic field strength are in quantitative agreement with a plasma fluid simulation, Differences in plasma transport through straight and curved ducts are discussed. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Cluggish, BP (reprint author), Archimedes Technol Grp, San Diego, CA 92121 USA. EM cluggish@archimedestechnology.com NR 24 TC 22 Z9 22 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0093-3813 J9 IEEE T PLASMA SCI JI IEEE Trans. Plasma Sci. PD DEC PY 1998 VL 26 IS 6 BP 1645 EP 1652 DI 10.1109/27.747882 PG 8 WC Physics, Fluids & Plasmas SC Physics GA 162DF UT WOS:000078329600007 ER PT J AU Tuszewski, M Henins, I Nastasi, M Scarborough, WK Walter, KC Lee, DH AF Tuszewski, M Henins, I Nastasi, M Scarborough, WK Walter, KC Lee, DH TI Inductive plasma sources for plasma implantation and deposition SO IEEE TRANSACTIONS ON PLASMA SCIENCE LA English DT Article DE inductive plasma sources; plasma deposition; plasma ion implantation ID ION-IMPLANTATION AB External and reentrant radio frequency inductive plasma sources are developed for plasma ion implantation and deposition processes in a 1.8 m(3) vacuum vessel. Plasma densities in the range 10(16)-10(17) m(-3) are desirable for the above processes. External plasma sources could not yield the required plasma densities because of high particle losses in the transition region between the source and the main vessel. The particle losses are clarified through experiments and analysis, with and without multipole magnetic confinement. Reentrant plasma sources eliminate transmission losses and yield high plasma densities with good spatial uniformity. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Tuszewski, M (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. EM mgtu@lanl.gov NR 14 TC 22 Z9 22 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 0093-3813 EI 1939-9375 J9 IEEE T PLASMA SCI JI IEEE Trans. Plasma Sci. PD DEC PY 1998 VL 26 IS 6 BP 1653 EP 1660 DI 10.1109/27.747883 PG 8 WC Physics, Fluids & Plasmas SC Physics GA 162DF UT WOS:000078329600008 ER PT J AU Schutze, A Jeong, JY Babayan, SE Park, J Selwyn, GS Hicks, RF AF Schutze, A Jeong, JY Babayan, SE Park, J Selwyn, GS Hicks, RF TI The atmospheric-pressure plasma jet: A review and comparison to other plasma sources SO IEEE TRANSACTIONS ON PLASMA SCIENCE LA English DT Article DE atmospheric pressure; corona discharge; dielectric barrier discharge; plasma jet; plasma torch; thermal and nonthermal plasmas; transferred arc ID CHEMICAL-VAPOR-DEPOSITION; CORONA DISCHARGE; TIO2 FILMS; DIAMOND; TORCH; ARC; TEMPERATURE; SPRAY; CVD; GENERATION AB Atmospheric-pressure plasmas are used in a variety of materials processes. Traditional sources include transferred arcs, plasma torches, corona discharges, and dielectric barrier discharges, In arcs and torches, the electron and neutral temperatures exceed 3000 degrees C and the densities of charge species range from 10(16)-10(19) cm(-3). Due to the high gas temperature, these plasmas are used primarily in metallurgy. Corona and dielectric barrier discharges produce nonequilibrium plasmas with gas temperatures between 50-400 degrees C and densities of charged species typical of weakly ionized gases. However, since these discharges are nonuniform, their use in materials processing is limited. Recently, an atmospheric-pressure plasma jet has been developed, which exhibits many characteristics of a conventional, low-pressure glow discharge. In the jet, the gas temperature ranges from 25-200 degrees C, charged-particle densities are 10(11)-10(12) cm(-3), and reactive species are present in high concentrations, i.e., 10-100 ppm. Since this source may be scaled to treat large areas, it could be used in applications which have been restricted to vacuum, In this paper, the physics and chemistry of the plasma jet and other atmospheric-pressure sources are reviewed. C1 Univ Calif Los Angeles, Dept Chem Engn, Los Angeles, CA 90095 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Schutze, A (reprint author), Univ Calif Los Angeles, Dept Chem Engn, Los Angeles, CA 90095 USA. NR 70 TC 637 Z9 656 U1 28 U2 297 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0093-3813 J9 IEEE T PLASMA SCI JI IEEE Trans. Plasma Sci. PD DEC PY 1998 VL 26 IS 6 BP 1685 EP 1694 DI 10.1109/27.747887 PG 10 WC Physics, Fluids & Plasmas SC Physics GA 162DF UT WOS:000078329600012 ER PT J AU Snyder, HR Anderson, SK AF Snyder, HR Anderson, SK TI Effect of air and oxygen content on the dielectric barrier discharge decomposition of chlorobenzene SO IEEE TRANSACTIONS ON PLASMA SCIENCE LA English DT Article DE atmospheric pressure plasmas; dielectric barrier discharge; plasma chemistry ID PLASMAS AB Experiments were performed on the plasma-assisted decomposition of dilute concentrations of chlorobenzene in air/oxygen and argon/oxygen gas mixtures at atmospheric pressure using a coaxial geometry single dielectric barrier discharge for different oxygen concentrations and energy densities. The results show that the decomposition process requires higher energy densities using air mixtures compared to argon/oxygen mixtures and is not linearly dependent on the oxygen content for a given energy density. The main decomposition products detected in the offgas were carbon dioxide and carbon monoxide. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Snyder, HR (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 10 TC 51 Z9 54 U1 1 U2 9 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0093-3813 J9 IEEE T PLASMA SCI JI IEEE Trans. Plasma Sci. PD DEC PY 1998 VL 26 IS 6 BP 1695 EP 1699 DI 10.1109/27.747888 PG 5 WC Physics, Fluids & Plasmas SC Physics GA 162DF UT WOS:000078329600013 ER PT J AU Wood, BP Pesenson, D AF Wood, BP Pesenson, D TI Cathodic-arc plasma density, radial profile, and total plasma inventory as measured by microwave interferometer and Faraday cup SO IEEE TRANSACTIONS ON PLASMA SCIENCE LA English DT Article DE arc discharges; microwave measurements; plasma measurements; vacuum arcs ID ION AB The total amount of plasma, peak plasma density, and plasma density radial profile are derived from a series of measurements of ion current density (with a Faraday cup) and integrated electron line density (with a microwave interferometer) for a cathodic are derived plasma, Comparisons are made between cathode material (erbium and titanium), are current, background gas pressure, and the presence or absence of a series magnetic solenoid around the coaxial anode and cathode. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Calif Irvine, Dept Math, Irvine, CA 92697 USA. RP Wood, BP (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. EM bwood@lanl.gov NR 10 TC 1 Z9 1 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0093-3813 J9 IEEE T PLASMA SCI JI IEEE Trans. Plasma Sci. PD DEC PY 1998 VL 26 IS 6 BP 1718 EP 1723 DI 10.1109/27.747891 PG 6 WC Physics, Fluids & Plasmas SC Physics GA 162DF UT WOS:000078329600016 ER PT J AU Carlsten, BE Ferguson, P Sprehn, D AF Carlsten, BE Ferguson, P Sprehn, D TI Accuracy of the equivalent circuit model using a fixed beam impedance for klystron gain cavities SO IEEE TRANSACTIONS ON PLASMA SCIENCE LA English DT Article DE cavity resonators; klystrons; microwave tubes; numerical analysis AB Most small-signal calculations of the modulation in a klystron's gain cavity use an equivalent circuit which includes a fixed beam impedance. Comparing this calculation to the gain calculated self-consistently, we note there are appreciable errors in both the calculated amplitude and phase of the cavity's modulation. These errors may lead to large accumulated errors in determining either the tube's small-signal or large-signal gain, Both techniques are used in a comparison with an existing S-band klystron. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. MDS Co, Oakland, CA 94611 USA. Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Carlsten, BE (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 20 TC 5 Z9 5 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0093-3813 J9 IEEE T PLASMA SCI JI IEEE Trans. Plasma Sci. PD DEC PY 1998 VL 26 IS 6 BP 1745 EP 1749 DI 10.1109/27.747895 PG 5 WC Physics, Fluids & Plasmas SC Physics GA 162DF UT WOS:000078329600020 ER PT J AU Jones, RE Wilson, RH Calton, TL AF Jones, RE Wilson, RH Calton, TL TI On constraints in assembly planning SO IEEE TRANSACTIONS ON ROBOTICS AND AUTOMATION LA English DT Article DE assembly planning; manufacturing; manufacturing; constraints; planning; user interfaces ID FRICTIONLESS ASSEMBLIES; SEQUENCES; GENERATION AB Constraints on assembly plans vary depending on product, assembly facility, assembly volume, and many other factors. Assembly costs and other measures to optimize vary just as widely. To be effective, computer-aided assembly planning systems must allow users to express the plan selection criteria that apply to their products and production environments. We begin this article by surveying the types of user criteria, both constraints and quality measures, that have been accepted by assembly planning systems to date. The survey is organized along several dimensions, including strategic versus tactical criteria; manufacturing requirements versus requirements of the automated planning process itself; and the information needed to assess compliance with each criterion. The latter strongly influences the efficiency of planning. We then focus on constraints, We describe a framework to support a wide variety of user constraints for intuitive and efficient assembly planning, Our framework expresses all constraints on a sequencing level, specifying orders and conditions on part mating operations in a number of ways. Constraints are implemented as simple procedures that either accept or reject assembly operations proposed by the planner. For efficiency, some constraints are supplemented with special-purpose modifications to the planner's algorithms, Fast replanning enables an interactive plan-vie cv-constrain-replan cycle that aids in constraint discovery and documentation, We describe an implementation of the framework in a computer-aided assembly planning system and experiments applying the system to a number of complex assemblies, including one with 472 parts. C1 Sandia Natl Labs, Intelligent Syst & Robot Ctr, Albuquerque, NM 87185 USA. RP Sandia Natl Labs, Intelligent Syst & Robot Ctr, POB 5800, Albuquerque, NM 87185 USA. NR 32 TC 27 Z9 29 U1 1 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1042-296X J9 IEEE T ROBOTIC AUTOM JI IEEE Trans. Robot. Autom. PD DEC PY 1998 VL 14 IS 6 BP 849 EP 863 DI 10.1109/70.736770 PG 15 WC Automation & Control Systems; Engineering, Electrical & Electronic; Robotics SC Automation & Control Systems; Engineering; Robotics GA 153NQ UT WOS:000077839500001 ER PT J AU Carroll, JM Rosson, MB Chin, G Koenemann, J AF Carroll, JM Rosson, MB Chin, G Koenemann, J TI Requirements development in scenario-based design SO IEEE TRANSACTIONS ON SOFTWARE ENGINEERING LA English DT Article DE participatory design; scenario-based design; requirements engineering; requirements development ID TASK AB We describe and analyze the process of requirements development in scenario-based design through consideration of a case study. In our project, a group of teachers and system developers initially set out to create a virtual physics laboratory. Our design work centered on the collaborative development of a series of scenarios describing current and future classroom activities. We observed classroom scenarios to assess needs and opportunities, and envisioned future scenarios to specify and analyze possible design moves. We employed claims analysis to evaluate design trade-offs implicit in these scenarios, to codify the specific advantages and disadvantages in achieving requirements. Through the course of this process, the nature of our project requirements has evolved, providing more information but also more kinds of information. We discuss the utility of managing requirements development through an evolving set of scenarios, and the generality of the scenario stages from this case study. C1 Virginia Polytech Inst & State Univ, Dept Comp Sci, Blacksburg, VA 24061 USA. Virginia Polytech Inst & State Univ, Ctr Human Comp Interact, Blacksburg, VA 24061 USA. Pacific NW Lab, Informat Sci & Engn Dept, Richland, WA 99352 USA. German Natl Res Ctr Informat Technol, FIT HCI, D-53754 St Augustin, Germany. RP Carroll, JM (reprint author), Virginia Polytech Inst & State Univ, Dept Comp Sci, Blacksburg, VA 24061 USA. RI Carroll, John/A-8718-2009 OI Carroll, John/0000-0001-5189-337X NR 42 TC 32 Z9 32 U1 0 U2 1 PU IEEE COMPUTER SOC PI LOS ALAMITOS PA 10662 LOS VAQUEROS CIRCLE, PO BOX 3014, LOS ALAMITOS, CA 90720-1314 USA SN 0098-5589 J9 IEEE T SOFTWARE ENG JI IEEE Trans. Softw. Eng. PD DEC PY 1998 VL 24 IS 12 BP 1156 EP 1170 DI 10.1109/32.738344 PG 15 WC Computer Science, Software Engineering; Engineering, Electrical & Electronic SC Computer Science; Engineering GA 151TW UT WOS:000077737600008 ER PT J AU Bishop, RL Flesner, RL Dell'Orco, PC Spontarelli, T Larson, SA Bell, DA AF Bishop, RL Flesner, RL Dell'Orco, PC Spontarelli, T Larson, SA Bell, DA TI Application of gas-liquid film theory to base hydrolysis of HMX powder and HMX-based plastic-bonded explosives using sodium carbonate SO INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH LA English DT Article ID KINETICS AB Sodium carbonate (Na2CO3) is identified as a hydrolysis reagent for decomposing HMX and HMX-base explosives to water-soluble, nonenergetic products. The reaction kinetics of Na2CO3 hydrolysis are examined, and a reaction rate model is developed. Greater than 99% of the explosive at an initial concentration of 10 wt % PBX 9404 was destroyed in less than 5 min at 150 degrees C. The primary products from Na2CO3 hydrolysis were nitrite (NO2), formate (HCOO-), nitrate (NO3-), and acetate (CH3COO-) ions, hexamethylenetetramine, (hexamine: C6H12N4), nitrogen gas (N-2), nitrous oxide (N2O), and ammonia (NH3). The rate of hydrolysis was characterized for HMX powder and PBX 9404 molding powder from 110 to 150 degrees C. The rate was found to be dependent on both the chemical kinetics and the mass transfer resistance. Since the HMX particles are nonporous and external mass transfer dominates, gas-liquid film theory for fast chemical kinetics was used to model the reaction rate. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Wyoming, Dept Chem & Petr Engn, Laramie, WY 82071 USA. RP Flesner, RL (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663,MS C920, Los Alamos, NM 87545 USA. NR 40 TC 6 Z9 6 U1 0 U2 4 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0888-5885 J9 IND ENG CHEM RES JI Ind. Eng. Chem. Res. PD DEC PY 1998 VL 37 IS 12 BP 4551 EP 4559 DI 10.1021/ie980351a PG 9 WC Engineering, Chemical SC Engineering GA 146NH UT WOS:000077436600004 ER PT J AU Shehata, AM McEligot, DM AF Shehata, AM McEligot, DM TI Mean structure in the viscous layer of strongly-heated internal gas flows. Measurements SO INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER LA English DT Article ID LAMINARIZATION AB Experiments for air flowing upward in a Vertical circular tube were conducted for heating rates causing significant property variation in primarily forced convection. Two entry Reynolds numbers were employed, concentrating on three heating rates of q(i)(+) = q(w)"/Gc(p,) (in) T-in approximate to 0.0018, 0.0035 and 0.0045, to give conditions considered to be 'turbulent', 'subturbulent' and 'laminarizing'. In addition to variation of integral parameters, results include the mean velocity and temperature distributions-needed to guide development of advanced turbulence models for this situation. However, comparison to a simple approach-a modified version of the van Driest model-shows useful agreement. (C) 1998 Published by Elsevier Science Ltd. C1 Univ Arizona, Dept Aerosp & Mech Engn, Tucson, AZ 85721 USA. Xerox Corp, Webster, NY 14580 USA. Idaho Natl Engn & Environm Lab Lockheed Martin Id, Idaho Falls, ID 83415 USA. Xerox Corp, Webster, NY 14580 USA. RP McEligot, DM (reprint author), Univ Arizona, Dept Aerosp & Mech Engn, Tucson, AZ 85721 USA. NR 50 TC 44 Z9 44 U1 1 U2 5 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0017-9310 J9 INT J HEAT MASS TRAN JI Int. J. Heat Mass Transf. PD DEC PY 1998 VL 41 IS 24 BP 4297 EP 4313 DI 10.1016/S0017-9310(98)00088-X PG 17 WC Thermodynamics; Engineering, Mechanical; Mechanics SC Thermodynamics; Engineering; Mechanics GA 142FH UT WOS:000077189000018 ER PT J AU Thakur, R Lusk, E Gropp, W AF Thakur, R Lusk, E Gropp, W TI I/O in parallel applications: The weakest link SO INTERNATIONAL JOURNAL OF HIGH PERFORMANCE COMPUTING APPLICATIONS LA English DT Article AB Parallel computers are increasingly being used to run large-scale applications that also have huge input/output (I/O) requirements. However, many applications obtain poor I/O performance on modem parallel machines. This two-part special issue of the International Journal of High Performance Computing Applications contains papers that describe the I/O requirements and the techniques used to perform I/O in real parallel applications. The authors first explain how the I/O application program interface (API) plays a critical role in enabling such applications to achieve high I/O performance. They describe how the commonly used UNIX I/O interface is inappropriate for parallel I/O and how an explicitly parallel API with support for collective I/O can help the underlying I/O hardware and software perform I/O efficiently. They then describe MPI-IO, a recently defined, standard, portable API specifically designed for high performance parallel I/O. They conclude with an overview of the papers in Part 1 and Part 2 of this special issue. C1 Argonne Natl Lab, Div Math & Comp Sci, Argonne, IL 60439 USA. RP Argonne Natl Lab, Div Math & Comp Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. OI Gropp, William/0000-0003-2905-3029 NR 30 TC 12 Z9 12 U1 1 U2 3 PU SAGE PUBLICATIONS LTD PI LONDON PA 1 OLIVERS YARD, 55 CITY ROAD, LONDON EC1Y 1SP, ENGLAND SN 1094-3420 EI 1741-2846 J9 INT J HIGH PERFORM C JI Int. J. High Perform. Comput. Appl. PD WIN PY 1998 VL 12 IS 4 BP 389 EP 395 DI 10.1177/109434209801200401 PG 7 WC Computer Science, Hardware & Architecture; Computer Science, Interdisciplinary Applications; Computer Science, Theory & Methods SC Computer Science GA 132DG UT WOS:000076614600001 ER PT J AU Noble, DR Torczynski, JR AF Noble, DR Torczynski, JR TI A lattice-Boltzmann method for partially saturated computational cells SO INTERNATIONAL JOURNAL OF MODERN PHYSICS C LA English DT Article; Proceedings Paper CT 7th International Conference on the Discrete Simulation of Fluids CY JUL 14-18, 1998 CL UNIV OXFORD, OXFORD, ENGLAND HO UNIV OXFORD DE lattice-Boltzmann; boundary conditions; suspensions ID BOUNDARY-CONDITIONS; SIMULATION; FLOWS; PERMEABILITY; GEOMETRIES; EQUATION; MODEL AB The lattice-Boltzmann (LB) method is applied to complex, moving geometries in which computational cells are partially filled with fluid. The LB algorithm is modified to include a term that depends on the percentage of the cell saturated with fluid. The method is useful for modeling suspended obstacles that do not conform to the grid. Another application is to simulations of flow through reconstructed media that are not easily segmented into solid and liquid regions. A detailed comparison is made with FIDAP simulation results for the flow about a periodic line of cylinders in a channel at a nonzero Reynolds number. Two cases are examined. In the first simulation, the cylinders are given a constant velocity along the axis of the channel, and the steady solution is acquired. The transient behavior of the system is then studied by giving the cylinders an oscillatory velocity. For both steady and oscillatory flows, the method provides excellent agreement with FIDAP simulation results, even at locations close to the surface of a cylinder. In contrast to steplike solutions produced using the "bounce-back" condition, the proposed condition gives close agreement with the smooth FIDAP predictions. Computed drag forces with the proposed condition exhibit apparent quadratic convergence with grid refinement rather than the linear convergence exhibited by other LB boundary conditions. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Noble, DR (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 24 TC 95 Z9 100 U1 2 U2 26 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA JOURNAL DEPT PO BOX 128 FARRER ROAD, SINGAPORE 912805, SINGAPORE SN 0129-1831 J9 INT J MOD PHYS C JI Int. J. Mod. Phys. C PD DEC PY 1998 VL 9 IS 8 BP 1189 EP 1201 DI 10.1142/S0129183198001084 PG 13 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA 199BL UT WOS:000080459500006 ER PT J AU Stockman, HW Glass, RJ Cooper, C Rajaram, H AF Stockman, HW Glass, RJ Cooper, C Rajaram, H TI Accuracy and computational efficiency in 3D dispersion via lattice-Boltzmann: Models for dispersion in rough fractures and double-diffusive fingering SO INTERNATIONAL JOURNAL OF MODERN PHYSICS C LA English DT Article; Proceedings Paper CT 7th International Conference on the Discrete Simulation of Fluids CY JUL 14-18, 1998 CL UNIV OXFORD, OXFORD, ENGLAND HO UNIV OXFORD DE fingering; dispersion; lattice-Boltzmann; efficiency; fractures; roughness ID POROUS-MEDIA; BOUNDARY-CONDITIONS; GAS; CONVECTION; SIMULATION; STABILITY; MIGRATION; TRANSPORT; CHANNELS; FLUIDS AB In the presence of buoyancy, multiple diffusion coefficients, and porous media, the dispersion of solutes can be remarkably complex. The lattice-Boltzmann (LB) method is ideal for modeling dispersion in flow through complex geometries; yet, LB models of solute fingers or slugs can suffer from peculiar numerical conditions (e.g., denormal generation) that degrade computational performance by factors of 6 or more. Simple code optimizations recover performance and yield simulation rates up to similar to 3 million site up dates per second on inexpensive, single-CPU systems. Two examples illustrate limits of the methods: (1) Dispersion of solute in a thin duct is often approximated with dispersion between infinite parallel plates. However, Doshi, Daiya and Gill (DDG) showed that for a smooth-walled duct, this approximation is in error by a factor of similar to 8. But in the presence of wall roughness (found in all real fractures), the DDG phenomenon can be diminished. (2) Double-diffusive convection drives "salt-fingering", a process for mixing of fresh-cold and warm-salty waters in many coastal regions. Fingering experiments are typically performed in Hele-Shaw cells, and can be modeled with the 2D (pseudo-3D) LB method with velocity-proportional drag forces. However, the 2D models cannot capture Taylor-Aris dispersion from the cell walls. We compare 2D and true 3D fingering models against observations from laboratory experiments. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Univ Nevada, Desert Res Inst, Reno, NV 89506 USA. Univ Colorado, Dept Civil Engn, Boulder, CO 80309 USA. RP Stockman, HW (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 28 TC 27 Z9 28 U1 1 U2 9 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA JOURNAL DEPT PO BOX 128 FARRER ROAD, SINGAPORE 912805, SINGAPORE SN 0129-1831 J9 INT J MOD PHYS C JI Int. J. Mod. Phys. C PD DEC PY 1998 VL 9 IS 8 BP 1545 EP 1557 DI 10.1142/S0129183198001394 PG 13 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA 199BL UT WOS:000080459500037 ER PT J AU Hasslacher, B Meyer, DA AF Hasslacher, B Meyer, DA TI Modeling dynamical geometry with lattice-gas automata SO INTERNATIONAL JOURNAL OF MODERN PHYSICS C LA English DT Article; Proceedings Paper CT 7th International Conference on the Discrete Simulation of Fluids CY JUL 14-18, 1998 CL UNIV OXFORD, OXFORD, ENGLAND HO UNIV OXFORD DE dynamical geometry; lattice gas; self-assembly; nonequilibrium dynamics; reversible evolution; emergence ID CELLULAR-AUTOMATA; MICROEMULSIONS; EQUATION; FLUIDS AB Conventional lattice-gas automata consist of particles moving discretely on a fixed lattice. While such models have been quite successful for a variety of fluid flow problems, there are other systems, e.g., flow in a flexible membrane or chemical self-assembly, in which the geometry is dynamical and coupled to the particle Bow. Systems of this type seem to call for lattice gas models with dynamical geometry. We construct such a model on one-dimensional (periodic) lattices and describe some simulations illustrating its nonequilibrium dynamics. C1 Univ Calif Los Alamos Natl Lab, Div Theoret, Inst Phys Sci, Los Alamos, NM 87545 USA. Univ Calif San Diego, Dept Math, Project Geometry & Phys, La Jolla, CA 92093 USA. RP Hasslacher, B (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, Inst Phys Sci, MS B213, Los Alamos, NM 87545 USA. RI Meyer, David/J-5809-2015 OI Meyer, David/0000-0003-4148-5617 NR 22 TC 8 Z9 8 U1 0 U2 0 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA JOURNAL DEPT PO BOX 128 FARRER ROAD, SINGAPORE 912805, SINGAPORE SN 0129-1831 J9 INT J MOD PHYS C JI Int. J. Mod. Phys. C PD DEC PY 1998 VL 9 IS 8 BP 1597 EP 1605 DI 10.1142/S0129183198001448 PG 9 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA 199BL UT WOS:000080459500042 ER PT J AU Donangelo, R Rasmussen, JO Stoyer, MA Hamilton, JH AF Donangelo, R Rasmussen, JO Stoyer, MA Hamilton, JH TI Cluster aspects of Cf-252 spontaneous fission SO INTERNATIONAL JOURNAL OF MODERN PHYSICS E-NUCLEAR PHYSICS LA English DT Article ID OCTUPOLE DEFORMATION; FRAGMENT PAIRS; ISOTOPES; YIELDS AB An analysis of the spontaneous Cf-252 fission into the Mo-Ba channel suggests the existence of two distinct modes of fission. The dominant one agrees with the general trend of fission fragment excitation energies. The second mode, occurring with a relative frequency of a few percent, is characterized by a total kinetic energy much lower than that of the first mode, with almost all of the difference appearing as excitation energy of the fragments. We argue that the second mode can be interpreted in terms of a cluster structure allowing long neck lengths at scission. C1 Univ Fed Rio de Janeiro, Inst Fis, BR-21945970 Rio De Janeiro, Brazil. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. Vanderbilt Univ, Dept Phys & Astron, Nashville, TN 37235 USA. RP Donangelo, R (reprint author), Univ Fed Rio de Janeiro, Inst Fis, CP 68528, BR-21945970 Rio De Janeiro, Brazil. NR 22 TC 6 Z9 6 U1 0 U2 0 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA JOURNAL DEPT PO BOX 128 FARRER ROAD, SINGAPORE 912805, SINGAPORE SN 0218-3013 J9 INT J MOD PHYS E JI Int. J. Mod. Phys. E-Nucl. Phys. PD DEC PY 1998 VL 7 IS 6 BP 669 EP 676 DI 10.1142/S0218301398000385 PG 8 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 166DU UT WOS:000078561600002 ER PT J AU Snider, DM O'Rourke, PJ Andrews, MJ AF Snider, DM O'Rourke, PJ Andrews, MJ TI Sediment flow in inclined vessels calculated using a multiphase particle-in-cell model for dense particle flows SO INTERNATIONAL JOURNAL OF MULTIPHASE FLOW LA English DT Article DE two-phase flow; Eulerian; Lagrangian; sedimentation ID SETTLING TANKS; WALLS; SUSPENSIONS AB Sedimentation of particles in an inclined vessel is predicted using a two-dimensional, incompressible? multiphase particle-in-cell (MP-PIC) method. The numerical technique solves the governing equations of the fluid phase using a continuum model and those of the particle phase using a Lagrangian model. Mapping particle properties to an Eulerian grid and then mapping back computed stress tensors to particle positions allows a complete solution of sedimentation from a dilute mixture to close-pack. The solution scheme allows for distributions of types, sizes and density of particles, with no numerical diffusion from the Lagrangian particle calculations. The MP-PIC solution method captures the physics of inclined sedimentation which includes the clarified fluid layer under the upper wall, a dense mixture layer above the bottom wall, and instabilities which produce waves at the clarified fluid and suspension interface. Measured and calculated sedimentation rates are in good agreement. (C) 1998 Published by Elsevier Science Ltd. All rights reserved. C1 Flow Anal, Albuquerque, NM 87109 USA. Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Texas A&M Univ, Dept Mech Engn, College Stn, TX 77843 USA. RP Snider, DM (reprint author), Flow Anal, 6504 Avenida La Costa NE, Albuquerque, NM 87109 USA. NR 27 TC 76 Z9 82 U1 2 U2 28 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0301-9322 J9 INT J MULTIPHAS FLOW JI Int. J. Multiph. Flow PD DEC PY 1998 VL 24 IS 8 BP 1359 EP 1382 DI 10.1016/S0301-9322(98)00030-5 PG 24 WC Mechanics SC Mechanics GA 154DF UT WOS:000077872800006 ER PT J AU Ponnaiya, B Limoli, CL Corcoran, J Kaplan, MI Hartmann, A Morgan, WF AF Ponnaiya, B Limoli, CL Corcoran, J Kaplan, MI Hartmann, A Morgan, WF TI The evolution of chromosomal instability in Chinese hamster cells: a changing picture? SO INTERNATIONAL JOURNAL OF RADIATION BIOLOGY LA English DT Article; Proceedings Paper CT Workshop on Genomic Instability CY OCT, 1998 CL CAPRI, ITALY SP European Late Effects Project Grp ID DELAYED REPRODUCTIVE DEATH; SURVIVING X-IRRADIATION; IONIZING-RADIATION; LETHAL MUTATIONS; ABERRATIONS; PHENOTYPE AB Purpose: To investigate the kinetics of chromosomal instability induced in clones of Chinese hamster cells following X-irradiation. Materials and methods: X-irradiated clones of GM10115, human-hamster hybrid cells containing a single human chromosome 4 (HC4), have been previously established. These clones were defined as unstable if they contained greater than or equal to three subpopulations of cells with unique rearrangements of HC4 as detected by FISH. Stable and unstable clones were analysed by FISH and Giemsa staining at various times post-irradiation. Results: While most of the stable clones continued to show chromosomal stability of HC4 over time, one became marginally unstable at approximately 45 population doublings postirradiation. Clones exhibiting chromosomal instability had one of several fates. Many of the unstable clones were showed similar levels of instability over time. However, one unstable clone became stable with time in culture, while another became even more unstable over time. Cytogenetic analyses of all clones after Giemsa staining indicated that in some clones the hamster chromosomes were rearranged independent of HC4, demonstrating increased frequencies of chromatid breaks and dicentric chromosomes. The majority of the unstable clones also had higher yields of chromatid gaps. Conclusions: These data demonstrate the dynamic nature of chromosomal instability as measured by two different cytogenetic assays. C1 Univ Calif San Francisco, Dept Radiat Oncol, San Francisco, CA 94143 USA. Univ Calif San Francisco, Dept Radiol, San Francisco, CA 94143 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, Berkeley, CA 94720 USA. RP Ponnaiya, B (reprint author), Univ Calif San Francisco, Dept Radiat Oncol, Box 0750, San Francisco, CA 94143 USA. FU NCI NIH HHS [CA 09215, CA 73924]; NIGMS NIH HHS [GM 54189] NR 24 TC 14 Z9 15 U1 0 U2 0 PU TAYLOR & FRANCIS LTD PI LONDON PA ONE GUNPOWDER SQUARE, LONDON EC4A 3DE, ENGLAND SN 0955-3002 J9 INT J RADIAT BIOL JI Int. J. Radiat. Biol. PD DEC PY 1998 VL 74 IS 6 BP 765 EP 770 DI 10.1080/095530098141041 PG 6 WC Biology; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Life Sciences & Biomedicine - Other Topics; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 150PL UT WOS:000077673700015 PM 9881722 ER PT J AU Brost, RC Peters, RR AF Brost, RC Peters, RR TI Automatic design of 3-D fixtures and assembly pallets SO INTERNATIONAL JOURNAL OF ROBOTICS RESEARCH LA English DT Article ID RESTRAINT ANALYSIS AB This paper presents an implemented algorithm that automatically designs fixtures and assembly pallets to hold three-dimensional parts. All fixtures generated by the algorithm employ round side locators, a side clamp, and cylindrical supports; depending on the value of an input-control flag, the fixture may also include swing-arm top clamps. Using these modular elements, the algorithm designs fixtures that rigidly constrain and locate a part, obey task constraints, are robust to part-shape variations, are easy to load, and are economical to produce. For the class of fixtures that are considered, the algorithm is guaranteed to find the global optimum design that satisfies these and other pragmatic conditions. We present the results of the algorithm applied to several practical manufacturing problems. For these complex problems, the algorithm typically returns initial high-quality fixture designs in less than a minute, and identifies the global optimum design in just over an hour The algorithm is also capable of solving difficult design problems where a single fixture is desired that can hold either of two parts. C1 Eastman Kodak Co, Albuquerque, NM 87112 USA. Sandia Natl Labs, Intelligent Syst & Robot Ctr, Albuquerque, NM 87185 USA. RP Eastman Kodak Co, 2901 Juan Tabo NE,Suite 210, Albuquerque, NM 87112 USA. NR 50 TC 15 Z9 15 U1 0 U2 2 PU SAGE PUBLICATIONS LTD PI LONDON PA 1 OLIVERS YARD, 55 CITY ROAD, LONDON EC1Y 1SP, ENGLAND SN 0278-3649 EI 1741-3176 J9 INT J ROBOT RES JI Int. J. Robot. Res. PD DEC PY 1998 VL 17 IS 12 BP 1243 EP 1281 DI 10.1177/027836499801701201 PG 39 WC Robotics SC Robotics GA 141VU UT WOS:000077165600001 ER PT J AU Berryman, JG Pride, SR AF Berryman, JG Pride, SR TI Volume averaging, effective stress rules, and inversion for microstructural response of multicomponent porous media SO INTERNATIONAL JOURNAL OF SOLIDS AND STRUCTURES LA English DT Article ID ELASTIC PROPERTIES; FLUID TRANSPORT; PORE-FLUID; ROCK; POROELASTICITY; EQUATIONS; THERMOELASTICITY; COMPRESSIBILITY; CONSTITUENTS AB A general volume-averaging technique is used to derive equations satisfied by the average scalar stresses and strains in multicomponent porous rock. The resulting equations are combined with general thought experiments to produce the effective-stress rules that determine the volumetric changes of the rock induced by changes in the confining and fluid pressures. The composite porous material specifically treated is an isotropic mixture of two Gassmann materials. Two distinct cases are considered depending on whether the grains at the interface between the Gassmann materials are either (1) welded together (no "cracks" can open between the two constituents) or (2) nonwelded (cracks can open). The effective-stress laws determine not only the overall volumetric changes of a given sample (i.e., changes in sample volume, total pore volume, and fluid-mass content), but determine as well the changes within each Gassmann component individually. This additional level of detail achieved in the analysis is referred to as inversion for the microstructural response. In the nonwelded case, the effective-stress law relating the variation of crack porosity with macroscopic changes in confining and fluid stress can be used to determine optimum strategies for increasing fracture/crack porosity with applications to reservoir production analysis. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Inst Phys Globe, Dept Geomagnetisme & Paleomagnetisme, F-75252 Paris 05, France. RP Lawrence Livermore Natl Lab, POB 808 L-200, Livermore, CA 94551 USA. EM berryman@s123.es.llnl.gov RI Berryman, James/A-9712-2008 NR 34 TC 15 Z9 15 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0020-7683 EI 1879-2146 J9 INT J SOLIDS STRUCT JI Int. J. Solids Struct. PD DEC PY 1998 VL 35 IS 34-35 BP 4811 EP 4843 DI 10.1016/S0020-7683(98)00096-1 PG 33 WC Mechanics SC Mechanics GA 120QZ UT WOS:000075969000017 ER PT J AU Erdman, DL Weitsman, Y AF Erdman, DL Weitsman, Y TI The multi-fracture response of cross-ply ceramic composites SO INTERNATIONAL JOURNAL OF SOLIDS AND STRUCTURES LA English DT Article ID REINFORCED GLASS-CERAMICS; MATRIX COMPOSITES; DAMAGE EVOLUTION; HIGH-STRENGTH; STRESS; TOUGHNESS; CRACKING; FRICTION AB The mechanical response of cross-ply SiC/CAS ceramic matrix composites was investigated experimentally and analytically. The experiments consisted of recording stress-strain behavior, counting matrix cracks and measuring the interlaminar shearing strength. The analysis employed an extended shear-lag model which incorporated non-linear behavior of the 0 degrees plies and interlaminar slip between the 0 and 90 degrees plies. The evolution of the multi-cracking process was determined by means of fracture criterion, leading to the prediction of the overall stress-strain response of the cross-ply laminate. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Univ Tennessee, Dept Aerosp Engn Mech & Engn Sci, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Weitsman, Y (reprint author), Univ Tennessee, Dept Aerosp Engn Mech & Engn Sci, 307 Perkins Hall, Knoxville, TN 37996 USA. EM weitsmana@utk.edu NR 52 TC 9 Z9 14 U1 0 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0020-7683 J9 INT J SOLIDS STRUCT JI Int. J. Solids Struct. PD DEC PY 1998 VL 35 IS 36 BP 5051 EP 5083 DI 10.1016/S0020-7683(97)00248-5 PG 33 WC Mechanics SC Mechanics GA 127VM UT WOS:000076371300002 ER PT J AU Burke, JJ Kehoe, HW O'Donovan, T AF Burke, JJ Kehoe, HW O'Donovan, T TI The effect of set size, set population and defoliation date on seed yield of the late maincrop potato cultivar Barna SO IRISH JOURNAL OF AGRICULTURAL AND FOOD RESEARCH LA English DT Article DE Barna; defoliation date; set population; set size; seed yield AB Field trials were conducted over three growing seasons to study the effects of three set sizes (30 to 40, 40 to 50, 50 to 60 mm), six population densities (ranging from 35 000 to 75 000 sets/ha) and three defoliation dates on yield in the seed grade (35 to 55 mm) of the late-maincrop potato cultivar Barna. The responses of seed yield to increases in set size, set population and delaying defoliation date varied between growing seasons. When yields were compared after eliminating the effects of set population and defoliation date, the 50 to 60 mm sets outyielded the 40 to 50 mm sets and these outyielded the 30 to 40 mm sets. Yield increased with initial increases in population density, then stabilised or declined with further increases. Defoliation date had a significant effect on tuber yield, with the largest yield being obtained at the earliest date. For all set sizes, tuber number in the seed grade increased significantly with increase in population density. The highest number of seed tubers was recorded at the earliest defoliation date. Set populations that provided optimum yield of tubers in the seed grade are presented for each set size. C1 TEAGASC, Oak Pk Res Ctr, Carlow, Ireland. RP Burke, JJ (reprint author), TEAGASC, Oak Pk Res Ctr, Carlow, Ireland. NR 6 TC 0 Z9 1 U1 0 U2 0 PU TEAGASC PI DUBLIN PA 19 SANDYMOUNT AVE, DUBLIN 4, IRELAND SN 0791-6833 J9 IRISH J AGR FOOD RES JI Irish J. Agr. Food Res. PD DEC PY 1998 VL 37 IS 2 BP 183 EP 189 PG 7 WC Agriculture, Multidisciplinary; Food Science & Technology SC Agriculture; Food Science & Technology GA 160AA UT WOS:000078207100004 ER PT J AU Dale, VH Parr, PD AF Dale, VH Parr, PD TI Preserving DOE's research parks SO ISSUES IN SCIENCE AND TECHNOLOGY LA English DT Article C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Dale, VH (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RI Dale, Virginia/B-6023-2009 NR 5 TC 21 Z9 22 U1 0 U2 0 PU NATL ACAD SCIENCES PI WASHINGTON PA 2101 CONSTITUTION AVE NW, WASHINGTON, DC 20418 USA SN 0748-5492 J9 ISSUES SCI TECHNOL JI Issues Sci. Technol. PD WIN PY 1998 VL 14 IS 2 BP 73 EP 77 PG 5 WC Engineering, Multidisciplinary; Engineering, Industrial; Multidisciplinary Sciences; Social Issues SC Engineering; Science & Technology - Other Topics; Social Issues GA YR412 UT WOS:000071492700041 ER PT J AU Ohzono, T Glosli, JN Fujihira, M AF Ohzono, T Glosli, JN Fujihira, M TI Simulations of wearless friction at a sliding interface between ordered organic monolayers SO JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS BRIEF COMMUNICATIONS & REVIEW PAPERS LA English DT Article DE friction; molecular dynamics simulation; phenomenological simulation; interlace; ordered organic monolayer ID ATOMIC-SCALE FRICTION; SELF-ASSEMBLED MONOLAYERS; MOLECULAR-DYNAMICS SIMULATIONS; LANGMUIR-BLODGETT MONOLAYERS; STICK-SLIP MOTION; FORCE MICROSCOPY; ENERGY-DISSIPATION; DIAMOND SURFACES; FUNDAMENTAL MECHANISMS; LATERAL STIFFNESS AB Molecular dynamics and simple phenomenological simulations are used to model the friction between two ordered monolayers of alkane chains bound at their ends to rigid substrates. Results of calculations using these methods suggest that the frictional properties at a sliding interface between the ordered films are governed by two simplified potentials. One isa potential due to the lateral collective deformation of a film and the other is a corrugated interfacial potential between films facing each other. These two potentials are closely related to the nature of the films, i.e., their physical and chemical properties. In addition, the simplified models can be greatly extended to clarify the frictional behavior of other weakly interacting interfaces such as hydrogen-terminated diamond surfaces. C1 Tokyo Inst Technol, Dept Biomol Engn, Midori Ku, Yokohama, Kanagawa 2268501, Japan. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Tokyo Inst Technol, Dept Biomol Engn, Midori Ku, 4259 Nagatsuta, Yokohama, Kanagawa 2268501, Japan. EM mfujihir@bio.titech.ac.jp RI Ohzono, Takuya/M-5400-2016 OI Ohzono, Takuya/0000-0003-2185-2504 NR 64 TC 18 Z9 18 U1 1 U2 4 PU JAPAN SOC APPLIED PHYSICS PI TOKYO PA KUDAN-KITA BUILDING 5TH FLOOR, 1-12-3 KUDAN-KITA, CHIYODA-KU, TOKYO, 102-0073, JAPAN SN 0021-4922 J9 JPN J APPL PHYS 1 JI Jpn. J. Appl. Phys. Part 1 - Regul. Pap. Brief Commun. Rev. Pap. PD DEC PY 1998 VL 37 IS 12A BP 6535 EP 6543 DI 10.1143/JJAP.37.6535 PG 9 WC Physics, Applied SC Physics GA 159TF UT WOS:000078190000048 ER PT J AU Taga, N Maekawa, M Shigesato, Y Yasui, I Kakei, M Haynes, TE AF Taga, N Maekawa, M Shigesato, Y Yasui, I Kakei, M Haynes, TE TI Deposition of heteroepitaxial In2O3 thin films by molecular beam epitaxy SO JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS SHORT NOTES & REVIEW PAPERS LA English DT Article DE In2O3; hetero epitaxial; molecular beam epitaxy; Rutherford backscattering; thin film; crystallinity; Volmer-Weber ID INDIUM-TIN OXIDE; YTTRIA-STABILIZED ZIRCONIA; LARGE-SCALE; TRANSPORT AB Highly oriented thin film In2O3 was heteroepitaxially grown on an optically polished (001) plane of single crystalline yttria stabilized zirconia (YSZ) substrate using molecular beam epitaxy (MBE). The full-width at half maximum (FWHM) of the X-ray rocking curve was 0.08 degrees for 200-nm-thick In2O3 layers indicating excellent uniformity of the crystallographic orientation compared with the heteroepitaxially-grown In2O3 deposited by a conventional method such as electron-beam (e-beam) evaporation. The minimum yield (chi(min)) of the MBE grown In2O3 film obtained from Rutherford backscattering (RBS) spectra was also extremely small with a value of 3.1% implying high crystallinity with very low lattice defect density. C1 Asahi Glass Co Ltd, Res Ctr, Kanagawa Ku, Yokohama, Kanagawa 2218755, Japan. Aoyama Gakuin Univ, Coll Sci & Engn, Setagaya Ku, Tokyo 1578572, Japan. Univ Tokyo, Inst Ind Sci, Minato Ku, Tokyo 1068558, Japan. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Taga, N (reprint author), Asahi Glass Co Ltd, Res Ctr, Kanagawa Ku, Yokohama, Kanagawa 2218755, Japan. RI Haynes, Tony/P-8932-2015 OI Haynes, Tony/0000-0003-2871-4745 NR 22 TC 35 Z9 36 U1 1 U2 11 PU JAPAN J APPLIED PHYSICS PI MINATO-KU TOKYO PA DAINI TOYOKAIJI BLDG 24-8 SHINBASHI 4-CHOME, MINATO-KU TOKYO, 105, JAPAN SN 0021-4922 J9 JPN J APPL PHYS 1 JI Jpn. J. Appl. Phys. Part 1 - Regul. Pap. Short Notes Rev. Pap. PD DEC PY 1998 VL 37 IS 12A BP 6524 EP 6529 DI 10.1143/JJAP.37.6524 PG 6 WC Physics, Applied SC Physics GA 159TF UT WOS:000078190000046 ER PT J AU Smith, LL AF Smith, LL TI Estimating US uranium reserves SO JOM-JOURNAL OF THE MINERALS METALS & MATERIALS SOCIETY LA English DT Article AB This article presents information on the Energy Information Administration's (U.S. Department of Energy) annual estimates of U.S. uranium reserves. Encompassed is information for year-end 1997's uranium reserves, which were estimated by employing numerous resources. C1 US DOE, Energy Informat Adm, Washington, DC 20585 USA. RP Smith, LL (reprint author), US DOE, Energy Informat Adm, 1000 Independence Ave SW, Washington, DC 20585 USA. EM lsmith@eia.doe.gov NR 4 TC 2 Z9 2 U1 0 U2 0 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 USA SN 1047-4838 J9 JOM-J MIN MET MAT S JI JOM-J. Miner. Met. Mater. Soc. PD DEC PY 1998 VL 50 IS 12 BP 41 EP 43 DI 10.1007/s11837-998-0306-6 PG 3 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Mineralogy; Mining & Mineral Processing SC Materials Science; Metallurgy & Metallurgical Engineering; Mineralogy; Mining & Mineral Processing GA 145PY UT WOS:000077381500009 ER PT J AU Simonen, EP Bruemmer, SM AF Simonen, EP Bruemmer, SM TI Radiation effects on environmental cracking of stainless steels SO JOM-JOURNAL OF THE MINERALS METALS & MATERIALS SOCIETY LA English DT Article ID STRESS-CORROSION CRACKING; SEGREGATION; IRRADIATION; ALLOYS AB Stainless steels exposed to radiation and hot water may fail by irradiation-assisted stress corrosion cracking. Cracking is especially evident in austenitic stainless steels exposed to light-water reactor irradiation and oxidizing water chemistry at temperatures near 288 degrees C. Neutron doses greater than one displacement per atom are typically required to induce observed cracking susceptibility. Thee evidence of a threshold dose suggests that radiation-induced material changes promote irradiation-assisted stress corrosion cracking, not radiation effects on water chemistry. Radiation-induced chromium depletion is considered the primary material change impacting this cracking. Impurity influences on solute segregation are apparent and may influence specific alloy susceptibility. Synergistic chemical/mechanical creep contributions to the intergranular failure mode are not important for light-water reactor conditions. C1 Pacific NW Lab, Richland, WA 99352 USA. RP Simonen, EP (reprint author), Pacific NW Lab, MS-P8-15, Richland, WA 99352 USA. NR 23 TC 4 Z9 5 U1 0 U2 3 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 USA SN 1047-4838 J9 JOM-J MIN MET MAT S JI JOM-J. Miner. Met. Mater. Soc. PD DEC PY 1998 VL 50 IS 12 BP 52 EP 55 DI 10.1007/s11837-998-0309-3 PG 4 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Mineralogy; Mining & Mineral Processing SC Materials Science; Metallurgy & Metallurgical Engineering; Mineralogy; Mining & Mineral Processing GA 145PY UT WOS:000077381500012 ER PT J AU Lillard, RS Butt, DP AF Lillard, RS Butt, DP TI The corrosion of materials in spallation neutron sources SO JOM-JOURNAL OF THE MINERALS METALS & MATERIALS SOCIETY LA English DT Article ID WATER; RADIOLYSIS AB Efforts to measure the real-time corrosion rates of alloy 718 during 800 MeV proton radiation at currents up to 1 mA are reported. Specially designed corrosion probes, which incorporate ceramic seals, were mounted in a wafer manifold that allowed samples to be directly exposed to the proton beam at the Los Alamos Neutron Science Center. The water system that supplied the manifold provided a means for controlling water chemistry, measuring dissolved hydrogen concentration, and measuring the effects of water radiolysis and water quality on corrosion rate. Real-time corrosion rate measurements during proton irradiation showed an exponential increase in corrosion rate with proton-beam current. These results are discussed within the context of water radiolysis at the diffusion boundary layer/beam-spot interface. However, additional factors that may influence these parameters, such as oxide spallation and charge build-up in the passive film, are not ruled out. C1 Univ Calif Los Alamos Natl Lab, Mat Corros & Environm Effects Lab, Los Alamos, NM 87545 USA. Univ Calif Los Alamos Natl Lab, Nonproliferat & Int Secur Div, Los Alamos, NM 87545 USA. RP Lillard, RS (reprint author), Univ Calif Los Alamos Natl Lab, Mat Corros & Environm Effects Lab, MS G755, Los Alamos, NM 87545 USA. EM lillard@lanl.gov RI Butt, Darryl/B-7480-2008 OI Butt, Darryl/0000-0003-4501-8864 NR 25 TC 7 Z9 7 U1 2 U2 5 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 USA SN 1047-4838 J9 JOM-J MIN MET MAT S JI JOM-J. Miner. Met. Mater. Soc. PD DEC PY 1998 VL 50 IS 12 BP 56 EP 59 DI 10.1007/s11837-998-0310-x PG 4 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Mineralogy; Mining & Mineral Processing SC Materials Science; Metallurgy & Metallurgical Engineering; Mineralogy; Mining & Mineral Processing GA 145PY UT WOS:000077381500013 ER PT J AU Bjormander, C Wittborn, J Rao, KV Dahlberg, ED AF Bjormander, C Wittborn, J Rao, KV Dahlberg, ED TI Slow relaxation of the polarization in pulsed laser ablated highly oriented ferroelectric thin films SO JOURNAL DE PHYSIQUE IV LA English DT Article; Proceedings Paper CT 2nd European Meeting on Integrated Ferroelectrics (EMIF2) CY SEP 28-30, 1997 CL JOUY EN JOSAS, FRANCE SP Siemens, Thomson-CSF AB The relaxation of the polarization (as determined by the pyroelectric effect) of high quality laser ablated films of PbZr0.52Ti0.48O3 has been measured after saturation with an applied electric field. The decay is observed to be quasilogrithmic over four decades in time. Analysis of measurements of the remanent polarization and the depolarization remanence are consistent with the depolarization field providing a polarization-state-dependent field of the correct direction to drive the decay. Also, the quasilogrithmic time dependence is consistent with a model for slow relaxation or creep with the depolarization field the driving field for the decay. These observations along with our AFM measurements imply that for maximum polarization stability a ferroelectric film should consist of decoupled grains. The optimum grain size should be the maximum grain size which does not support domain walls. C1 Argonne Natl Lab, Argonne, IL 60439 USA. Univ Minnesota, Tate Lab Phys, Minneapolis, MN 55455 USA. Royal Inst Technol, Dept Condensed Matter Phys, S-10044 Stockholm, Sweden. RP Bjormander, C (reprint author), Argonne Natl Lab, Argonne, IL 60439 USA. RI Rao, K.V./F-4577-2011 NR 16 TC 0 Z9 0 U1 0 U2 1 PU E D P SCIENCES PI LES ULIS CEDEXA PA 7, AVE DU HOGGAR, PARC D ACTIVITES COURTABOEUF, BP 112, F-91944 LES ULIS CEDEXA, FRANCE SN 1155-4339 J9 J PHYS IV JI J. Phys. IV PD DEC PY 1998 VL 8 IS P9 BP 89 EP 99 DI 10.1051/jp4:1998915 PG 11 WC Physics, Multidisciplinary SC Physics GA 158LZ UT WOS:000078118100016 ER PT J AU Hames, BR Kurek, B Pollet, B Lapierre, C Monties, B AF Hames, BR Kurek, B Pollet, B Lapierre, C Monties, B TI Interaction between MnO2 and oxalate: Formation of a natural and abiotic lignin oxidizing system SO JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY LA English DT Article DE manganese dioxide; oxalate; abiotic oxidation; poplar wood; lignin; cellulose; hemicellulose ID ACID-INSOLUBLE LIGNIN; PHANEROCHAETE-CHRYSOSPORIUM; MANGANESE PEROXIDASE; OXALIC-ACID; WHITE-ROT; BROWN-ROT; THIOACIDOLYSIS PRODUCTS; OXIDATIVE CLEAVAGE; ALDITOL ACETATES; SPRUCE LIGNINS AB This paper reports for the first time the efficient modification/degradation of in situ lignin by manganese complexes formed by the association of MnO2, accumulated as black deposits during wood decay, and oxalic acid, produced by fungi or resulting from oxidative degradation of cell wall components. The Mn oxidants formed are shown to modify both the chemical and physical properties of the wood cell wall. Microscopic analysis revealed the disruption of ray cell in oxidized wood and the formation of amorphous globular material not yet characterized. Thioacidolysis analysis of the oxidized lignin showed a reduction up to 25-30% in the recovery of ether-linked guaiacyl (G) and syringyl monomers and up to 50-80% of Several diarylpropane and phenylcoumarane dimers composing the polymer. Preferential oxidation of G moieties in all structures examined was observed during catalysis. The MnO2/oxalate system also appears to selectively oxidize the lignin macromolecule, as no xylose or glucose loss was observed in all treated samples. The oxidation process catalyzed by MnO2 and oxalate may play an important role in the general pathway of lignin degradation and also in the transformation of the lignin polymer into humus and/or its precursors. C1 Natl Renewable Energy Lab, Ctr Renewable Chem TEchnol & Mat, Golden, CO 80401 USA. INRA Paris Grignon, Ctr Biotechnol Agroind, Chim Biol Lab, F-78850 Thiverval Grignon, France. RP Kurek, B (reprint author), INRA, Equipe Biochim Macromol Vegetales, Unite Physicochim & Biotechnol Polymeres, 2 Esplanade Roland Garros, F-51686 Reims 2, France. EM kurek@reims.inra.fr NR 46 TC 13 Z9 13 U1 2 U2 15 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0021-8561 J9 J AGR FOOD CHEM JI J. Agric. Food Chem. PD DEC PY 1998 VL 46 IS 12 BP 5362 EP 5367 DI 10.1021/jf9806513 PG 6 WC Agriculture, Multidisciplinary; Chemistry, Applied; Food Science & Technology SC Agriculture; Chemistry; Food Science & Technology GA 150ZZ UT WOS:000077697600095 ER PT J AU Thiyagarajan, P Crawford, RK Mildner, DFR AF Thiyagarajan, P Crawford, RK Mildner, DFR TI Neutron transmission of a single-crystal MgO filter SO JOURNAL OF APPLIED CRYSTALLOGRAPHY LA English DT Article AB The neutron transmission probability through a single-crystal MgO filter has been measured at both liquid-nitrogen (77 K) and room (300 K) temperatures, as a function of wavelength, using a pulsed neutron source. The data show that a cooled MgO filter is superior to room-temperature sapphire for both thermal and cold neutrons, principally because the absorption probability is reduced by a factor of three at long wavelengths. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Argonne Natl Lab, Intense Pulsed Neutron Source, Argonne, IL 60439 USA. RP Mildner, DFR (reprint author), Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. NR 7 TC 13 Z9 13 U1 0 U2 0 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0021-8898 J9 J APPL CRYSTALLOGR JI J. Appl. Crystallogr. PD DEC 1 PY 1998 VL 31 BP 841 EP 844 DI 10.1107/S0021889898005858 PN 6 PG 4 WC Chemistry, Multidisciplinary; Crystallography SC Chemistry; Crystallography GA 157ND UT WOS:000078067800004 ER PT J AU Parkin, S Hope, H AF Parkin, S Hope, H TI Macromolecular cryocrystallography: Cooling, mounting, storage and transportation of crystals SO JOURNAL OF APPLIED CRYSTALLOGRAPHY LA English DT Article ID CRYSTALLOGRAPHY AB Simple methods are presented for handling, mounting, storage and transportation of crystals at cryogenic temperatures. They are easy to learn and have a number of technical and operational advantages over currently popular methods. In particular, the temperature of the crystal throughout all manipulations is known; it is shown never to rise above that of the warmest component of the cryogenic system, typically the cold gas stream of the low-temperature apparatus. Crystals can be mounted and inspected in the home laboratory prior to transportation to a synchrotron, giving dramatic savings in experimental time and effort. Provided appropriate care is taken, crystals remain frost free throughout any number of mount-dismount cycles. C1 Univ Calif Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, Livermore, CA 94550 USA. Univ Calif Davis, Dept Chem, Davis, CA 95616 USA. RP Parkin, S (reprint author), Duke Univ, Dept Biochem, Durham, NC 27710 USA. RI Parkin, Sean/E-7044-2011 NR 17 TC 53 Z9 55 U1 0 U2 3 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0021-8898 J9 J APPL CRYSTALLOGR JI J. Appl. Crystallogr. PD DEC 1 PY 1998 VL 31 BP 945 EP 953 DI 10.1107/S0021889898005305 PN 6 PG 9 WC Chemistry, Multidisciplinary; Crystallography SC Chemistry; Crystallography GA 157ND UT WOS:000078067800018 ER PT J AU Kim, DE Kim, DS Osterheld, AL AF Kim, DE Kim, DS Osterheld, AL TI Characteristics of populations and gains in neon-like argon (Ar IX) SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID WAVELENGTH LASER CALCULATIONS; X-RAY AMPLIFIER; PREPULSE TECHNIQUE; IONS AB The characteristics of the populations and gain coefficients in Ne-like Ar have been investigated considering the 37 levels of the 2p(6), 2p(5)3s, 2p(5)3p, 2p(5)3d, 2s2p(6)3s, 2s2p(6)3p, and 2s2p(6)3d configurations. It was found that large gains on the 3p S-1(0)-3s P-1(1), 3p P-3(2)-3s P-1(1) and 3p D-3(2)-3s P-3(1) transitions are formed for the density between 10(18) and 10(19) cm(-3). The effect of the opacities of the 2p S-1(0)-3s P-3(1), 2p S-1(0)-3s P-1(1), 2p S-1(0)-3d D-3(1) 2p S-1(0)-3d P-1(1), and 2p S-1(0)-2s3p P-1(1) transitions becomes important for a density higher than 10(18) cm(-3) and even increases the gain on the 3p S-1(0)-3s P-1(1) transition for the opacity of the 2p S-1(0)-3s P-1(1) transition of up to 2. (C) 1998 American Institute of Physics. [S0021-8979(98)02423-2] C1 Pohang Univ Sci & Technol, Dept Phys, Pohang 790784, South Korea. Youngwol Inst Technol, Dept Off Automat, Youngwol 230800, Kangwon Do, South Korea. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Kim, DE (reprint author), Pohang Univ Sci & Technol, Dept Phys, Pohang 790784, South Korea. EM kimd@vision.postech.ac.kr NR 22 TC 13 Z9 15 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD DEC 1 PY 1998 VL 84 IS 11 BP 5862 EP 5866 DI 10.1063/1.368900 PG 5 WC Physics, Applied SC Physics GA 137RN UT WOS:000076930100003 ER PT J AU Hecht, B Bielefeldt, H Pohl, DW Novotny, L Heinzelmann, H AF Hecht, B Bielefeldt, H Pohl, DW Novotny, L Heinzelmann, H TI Influence of detection conditions on near-field optical imaging SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID MICROSCOPE ISTOM; TNOM-2; MODE; RESOLUTION; FORCE; PROBE AB The process of image formation in transmission mode scanning near-field optical microscopy is analyzed both theoretically and experimentally. Changes in the dielectric and topographic properties of the sample influence not only the total transmitted intensity, but also its angular distribution in the far field. This opens up an additional source of optical information about the sample. Some of this additional information is retrieved by separate but simultaneous detection of the radiation emitted at angles smaller (allowed light) and larger (forbidden light) than the critical angle of total internal reflection, respectively. Different experimental setups and their respective advantages are discussed. High resolution, constant height mode optical images of test structures are compared with theoretical predictions. Forbidden-light optical images frequently provide enhanced resolution and/or contrast as compared to allowed light images. For small phase objects, in contrast to amplitude objects, a contrast reversal between forbidden and allowed light images is observed. (C) 1998 American Institute of Physics. [S0021-8979(98)02923-5] C1 IBM Corp, Div Res, Zurich Res Lab, CH-8803 Ruschlikon, Switzerland. Pacific NW Lab, Richland, WA 99352 USA. Univ Basel, Inst Phys, CH-4056 Basel, Switzerland. RP Hecht, B (reprint author), Swiss Fed Inst Technol, Dept Phys Chem, CH-8092 Zurich, Switzerland. RI Hecht, Bert/B-4996-2010 OI Hecht, Bert/0000-0002-4883-8676 NR 33 TC 38 Z9 38 U1 0 U2 6 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD DEC 1 PY 1998 VL 84 IS 11 BP 5873 EP 5882 DI 10.1063/1.368902 PG 10 WC Physics, Applied SC Physics GA 137RN UT WOS:000076930100005 ER PT J AU Cluggish, BP Munson, CP AF Cluggish, BP Munson, CP TI Sheath overlap during very large scale plasma source ion implantation SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID SIMULATIONS; GEOMETRIES; PLANAR; MODEL AB Measurements of plasma source ion implantation have been performed on a large target of complex geometry. The target consists of 1000 aluminum, automotive piston surrogates mounted on four racks; total surface area is over 16 m(2). The four racks are positioned parallel to each other, 0.25 m apart, in an 8 m(3) vacuum chamber. The racks of pistons are immersed in a capacitive radio frequency plasma, with an argon gas pressure of 20-65 mPa. Langmuir probe measurements indicate that the plasma density profile is highly nonuniform, due to particle losses to the racks of pistons. The plasma ions are implanted into the pistons by pulse biasing the workpiece to negative voltages as low as -18 kV for up to 20 mu s. During the voltage pulse, the high-voltage sheaths from adjacent racks of pistons converge towards each other. At plasma densities less than 10(9) cm(-3) the sheaths are observed to overlap. Measurements of the sheath overlap time are compared with standard analytic theory and with simulations run with a two-dimensional particle-in-cell code. [S0021-8979(98)08523-5] C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Cluggish, BP (reprint author), Archimedes Technol Grp, 5405 Oberlin Dr, San Diego, CA 92121 USA. NR 27 TC 6 Z9 6 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD DEC 1 PY 1998 VL 84 IS 11 BP 5937 EP 5944 DI 10.1063/1.368910 PG 8 WC Physics, Applied SC Physics GA 137RN UT WOS:000076930100014 ER PT J AU Cluggish, BP Munson, CP AF Cluggish, BP Munson, CP TI Secondary electron enhanced discharges in plasma source ion implantation SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID GLOW-DISCHARGE; SIMULATIONS; BOMBARDMENT; EMISSION; MODEL AB The first published measurements of a plasma discharge enhanced by secondary electrons during plasma source ion implantation are presented. The ion implantation target consists of 1000 aluminum, automotive piston surrogates mounted on four racks; total surface area is over 16 m(2). The four racks are positioned parallel to each other, 0.25 m apart, in an 8 m(3) vacuum chamber. The racks of pistons are immersed in a capacitive radio frequency plasma, with an argon gas pressure of 20-65 mPa. Each plasma ion implanted into the target results in the emission of multiple secondary electrons. Langmuir probe measurements indicate that at high enough gas pressures, the energy of the secondary electrons can couple to the plasma, increasing the rate of ionization. Two different coupling mechanisms are observed. In the first, the secondary electrons directly ionize the background gas. In the second, the secondary electrons couple to the thermal electrons through a beam-plasma instability. Measurements of the instabilities are in agreement with two-dimensional particle-in-cell simulations. [S0021-8979(98)08623-X] C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Cluggish, BP (reprint author), Archimedes Technol Grp, 5405 Oberlin Dr, San Diego, CA 92121 USA. NR 33 TC 12 Z9 13 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD DEC 1 PY 1998 VL 84 IS 11 BP 5945 EP 5955 DI 10.1063/1.368889 PG 11 WC Physics, Applied SC Physics GA 137RN UT WOS:000076930100015 ER PT J AU Keidar, M Beilis, II Brown, IG AF Keidar, M Beilis, II Brown, IG TI Multiply charged ion transport in free boundary vacuum arc plasma jet SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID STATE DISTRIBUTIONS AB The free boundary plasma arc jet expansion was analyzed based on a two-dimensional hydrodynamic model. The plasma jet expansion was modeled using the sourceless steady-state hydrodynamic equations, where the plasma free boundary was determined self-consistently. Due to the existence of an electric field in the quasineutral plasma the different charged ion species can be spatially separated. It was found that the mean charge state distribution is strongly nonuniform with a tendency for the highly charged species to appear near the plasma jet boundary region. Along the center line the density of singly charged ions falls off by about four times while the density of fourfold charged ions drops by more than 100 times. The radial charge state distribution becomes more nonuniform with increasing magnetic field. Good qualitative agreement between calculated and experimental radial distributions of different charged species was obtained. (C) 1998 American Institute of Physics. [S0021-8979(98)07323-X] C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Tel Aviv Univ, Elect Discharge & Plasma Lab, IL-69978 Tel Aviv, Israel. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Keidar, M (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, M-S-53, Berkeley, CA 94720 USA. NR 13 TC 10 Z9 10 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD DEC 1 PY 1998 VL 84 IS 11 BP 5956 EP 5960 DI 10.1063/1.368890 PG 5 WC Physics, Applied SC Physics GA 137RN UT WOS:000076930100016 ER PT J AU Ahrenkiel, SP Norman, AG Al-Jassim, MM Mascarenhas, A Mirecki-Millunchick, J Twesten, RD Lee, SR Follstaedt, DM Jones, ED AF Ahrenkiel, SP Norman, AG Al-Jassim, MM Mascarenhas, A Mirecki-Millunchick, J Twesten, RD Lee, SR Follstaedt, DM Jones, ED TI Laterally modulated composition profiles in AlAs/InAs short-period superlattices SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID MOLECULAR-BEAM EPITAXY; QUANTUM WIRES; GROWTH; LAYERS; ALLOYS AB Laterally modulated composition profiles in AlAs/InAs short-period superlattices grown by molecular-beam epitaxy under tensile strain on (001) InP are examined by transmission electron microscopy (TEM) and x-ray diffraction K mapping. Weak, one-dimensional modulation with a wavelength of lambda(m) = 110 Angstrom is observed for a period of 1 ML. At 2 ML, the composition profile is irregular, while a two-dimensional network of wire and dot structures with lambda(m) = 130 Angstrom occurs at 3 ML. At a high growth rate, 4-ML samples exhibit smooth modulated profiles with lambda(m) = 220 Angstrom. When the growth rate is reduced with beam interrupts, sharp profiles develop that show strong alignment in the substrate plane with lambda(m) = 270 Angstrom. TEM dark-field image contrast of the modulated profiles is simulated using dynamical diffraction theory to reproduce features observed in experiment. (C) 1998 American Institute of Physics. [S0021-8979(98)02123-9]. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Ahrenkiel, SP (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. EM phil_ahrenkiel@nrel.gov RI Norman, Andrew/F-1859-2010 OI Norman, Andrew/0000-0001-6368-521X NR 17 TC 30 Z9 30 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD DEC 1 PY 1998 VL 84 IS 11 BP 6088 EP 6094 DI 10.1063/1.368921 PG 7 WC Physics, Applied SC Physics GA 137RN UT WOS:000076930100037 ER PT J AU Fleetwood, DM Winokur, PS Riewe, LC Reber, RA AF Fleetwood, DM Winokur, PS Riewe, LC Reber, RA TI Bulk oxide traps and border traps in metal-oxide-semiconductor capacitors SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID POSTIRRADIATION ANNEALING RESPONSE; IRRADIATED MOS DEVICES; SILICON DIOXIDE; RADIATION RESPONSE; SI/SIO2 INTERFACE; ATOMIC-HYDROGEN; POSITIVE CHARGE; THIN-FILMS; ELECTRON; SIO2 AB Thermally stimulated current (TSC) and capacitance-voltage measurements are combined via a newly developed analysis technique to estimate positive and negative oxide-trap charge densities for metal-oxide-semiconductor (MOS) capacitors exposed to ionizing radiation or subjected to high-field stress. Significantly greater hole trapping than electron trapping is observed in 3% borosilicate glass (BSG) insulators. Two prominent TSC peaks are observed in these BSG films. A ;high-temperature peak near 250 degrees C is attributed to the E'(gamma) defect, which is a trivalent Si center in SiO2 associated with an O vacancy. A lower temperature positive charge center near 100 degrees C in these films is likely to be impurity related. The higher temperature E'(gamma) peak is also observed in 10, 17, and 98 nm thermal oxides. A much weaker secondary peak is observed near similar to 60 degrees C in some devices, which likely is due to metastably trapped holes in the bulk of the SiO2. Negative charge densities in these thermal oxides are primarily associated with electrons in border traps, which do not contribute to TSC, as opposed to bulk electron traps, which can contribute to TSC. Ratios of electron to hole trap densities in the thermal oxides range from similar to 30% for radiation exposure to greater than 80% for high-field stress. It is suggested that the large densities of border traps associated with trapped holes in these devices may be due to high space-charge induced electric fields near the Si/SiO2 interface. In some instances, border traps can reduce near-interfacial electric fields by local compensation of trapped positive charge. This may provide a natural explanation for the large densities of border traps often observed in irradiated or electrically stressed MOS capacitors. (C) 1998 American Institute of Physics. [S0021-8979(98)03423-9]. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Fleetwood, DM (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. EM dmfleet@sandia.gov NR 45 TC 38 Z9 38 U1 1 U2 26 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD DEC 1 PY 1998 VL 84 IS 11 BP 6141 EP 6148 DI 10.1063/1.368881 PG 8 WC Physics, Applied SC Physics GA 137RN UT WOS:000076930100045 ER PT J AU Gaburro, Z You, HD Babic, D AF Gaburro, Z You, HD Babic, D TI Effect of resistivity and current density on photoluminescence in porous silicon produced at low HF concentration SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID X-RAY-SCATTERING; QUANTUM CONFINEMENT; DISSOLUTION; LAYERS; LUMINESCENCE; POROSITY AB An experimental study of the intensity of photoluminescence (PL) of porous silicon prepared from an anodic dissolution of Si at low HF concentration (12.5%) of p-type (100) 0.01, 1 and 10 Ohm cm substrates as a function of substrate resistivity and etching current density has been performed. Based on the experimental results a photoluminescence efficiency diagram is proposed. Etching of p(+)-type silicon samples without light illumination produces PSi layers whose PL spectra show interference fringes. Comparison of the fringes in PL and in light reflectivity demonstrates unambiguously that they originate from the interference of the light reflected at the PSi/ bulk Si interface and depend on the thickness of the PSi layer. The intensity and frequency of the interference fringes are found to be strongly dependent on the anodization current. Implications of PSi layer fabrication at low HF concentration are discussed. (C) 1998 American Institute of Physics. [S0021-8979(98)06623- 7]. C1 Univ Illinois, Dept Elect Engn & Comp Sci, Chicago, IL 60607 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Gaburro, Z (reprint author), Univ Illinois, Dept Elect Engn & Comp Sci, Chicago, IL 60607 USA. RI You, Hoydoo/A-6201-2011 OI You, Hoydoo/0000-0003-2996-9483 NR 33 TC 25 Z9 27 U1 0 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD DEC 1 PY 1998 VL 84 IS 11 BP 6345 EP 6350 DI 10.1063/1.368960 PG 6 WC Physics, Applied SC Physics GA 137RN UT WOS:000076930100078 ER PT J AU Maya, L Riester, L Thundat, T Yust, CS AF Maya, L Riester, L Thundat, T Yust, CS TI Characterization of sputtered amorphous platinum dioxide films SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID OXIDE-FILMS; BEHAVIOR AB Amorphous platinum dioxide, a-PtO2, films are formed commonly during reactive sputtering of platinum at relatively high power density levels and high oxygen partial pressures. The structure of a-PtO2 is intermediate between the crystalline alpha and beta phases of this compound and either phase may form upon annealing or by lowering the power density during sputtering. Amorphous platinum dioxide is a semiconductor, and its resistivity depends on deposition parameters. Films of a-PtO2 are dense, chemically resistant, smooth, reflective, and have a hardness similar to titanium nitride. The films may be reduced in hydrogen at room temperature or in carbon monoxide at 200 degrees C to produce metallic platinum with crystallite sizes in the range of 5-10 nm. Any of these properties may be exploited to produce films that could be used in the development of sensors, optical materials, and in microelectronics. (C) 1998 American Institute of Physics. [S0021-8979(98)03223-X]. C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. Oak Ridge Natl Lab, Div Life Sci, Oak Ridge, TN 37831 USA. RP Maya, L (reprint author), Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. EM mayal@ornl.gov NR 18 TC 35 Z9 35 U1 2 U2 8 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD DEC 1 PY 1998 VL 84 IS 11 BP 6382 EP 6386 DI 10.1063/1.368883 PG 5 WC Physics, Applied SC Physics GA 137RN UT WOS:000076930100084 ER PT J AU Barnard, JC Wendell, LL Morris, VR AF Barnard, JC Wendell, LL Morris, VR TI Optimal filtering of AC output anemometers SO JOURNAL OF ATMOSPHERIC AND OCEANIC TECHNOLOGY LA English DT Article AB The output of pulsed and AC output anemometers suffer from discretization noise when such anemometers are sampled at fast rates (>1 Hz). This paper describes the construction of an optimal filter designed to reduce this noise. By comparing the filtered output from an AC output cup anemometer with a nearby cup anemometer whose output is free from discretization noise, it is shown that the filter significantly reduces the noise. Wind speed time series obtained from the two anemometers are quite similar Next, deconvolution is applied to the filtered time series to account for the anemometer response. Spectra from the deconvolved time series and a time series measured by a nearby sonic anemometer are compared, and for high-speed flows the spectra from the two instruments match quite well. The time series are also very similar; however, the cup anemometer generally cannot respond to the quick bursts of speed seen by the sonic anemometer. The filtering and deconvolution methods presented here are most appropriate for the high-speed flows relevant to wind energy studies. These methods make it possible to use inexpensive, rugged cup anemometers to measure a high-speed, turbulent wind field up to a frequency of about 5 Hz. C1 Pacific NW Lab, Richland, WA 99352 USA. RP Barnard, JC (reprint author), Pacific NW Lab, MSIN K-9 30,POB 999, Richland, WA 99352 USA. EM jc-barnard@pnl.gov NR 12 TC 4 Z9 4 U1 0 U2 1 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0739-0572 J9 J ATMOS OCEAN TECH JI J. Atmos. Ocean. Technol. PD DEC PY 1998 VL 15 IS 6 BP 1261 EP 1271 DI 10.1175/1520-0426(1998)015<1261:OFOAOA>2.0.CO;2 PG 11 WC Engineering, Ocean; Meteorology & Atmospheric Sciences SC Engineering; Meteorology & Atmospheric Sciences GA 165LM UT WOS:000078522500004 ER PT J AU Schwartz, SH Black, TA Jager, K Panoff, JM Wolk, CP AF Schwartz, SH Black, TA Jager, K Panoff, JM Wolk, CP TI Regulation of an osmoticum-responsive gene in Anabaena sp. strain PCC 7120 SO JOURNAL OF BACTERIOLOGY LA English DT Article ID CYANOBACTERIUM ANABAENA; ESCHERICHIA-COLI; HETEROCYST DEVELOPMENT; CONJUGAL TRANSFER; SALT; PROTEIN; GLUCOSYLGLYCEROL; PCC-7120; PCC-6803; STRESS AB Salt-induced genes in the cyanobacterium Anabaena sp, strain PCC 7120 were identified by use of a Tn5-based transposon bearing luxAB as a reporter. The genomic sequence adjacent to one site of insertion of the transposon was identical in part to the sequence of the lti2 gene, which was previously identified in a differential screen for cold-induced transcripts in Anabaena variabilis. The lti2-like gene was induced by sucrose and other osmotica and by low temperature, in addition to salt, Regulatory components necessary fur the induction of this gene by osmotica were sought by a further round of transposon mutagenesis, One mutant that displayed reduced transcriptional activity of the lti2-like gene in response to exposure to osmotica had an insertion in an open reading frame, which was denoted orrA, whose predicted product showed sequence similarity to response regulators from two-component regulatory systems. The corresponding mutation was reconstructed and was shown, like the secund-site transposon mutation, to result in reduced response to osmotic stress, Induction of the hn reporter gene by osmotica was restored by complementation with a genomic fragment containing the entire open reading frame for the presumptive response regulator, whereas a fragment containing a truncated copy of the open reading frame for the response regulator did not complement the mutation. C1 Michigan State Univ, MSU DOE, Plant Res Lab, E Lansing, MI 48824 USA. RP Wolk, CP (reprint author), Michigan State Univ, MSU DOE, Plant Res Lab, E Lansing, MI 48824 USA. EM wolk@pilot.msu.edu NR 46 TC 20 Z9 25 U1 1 U2 3 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1752 N ST NW, WASHINGTON, DC 20036-2904 USA SN 0021-9193 J9 J BACTERIOL JI J. Bacteriol. PD DEC PY 1998 VL 180 IS 23 BP 6332 EP 6337 PG 6 WC Microbiology SC Microbiology GA 142TZ UT WOS:000077217600031 PM 9829944 ER PT J AU Seaborg, GT AF Seaborg, GT TI A long career in chemistry and education SO JOURNAL OF CHEMICAL EDUCATION LA English DT Biographical-Item C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Seaborg, GT (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0021-9584 J9 J CHEM EDUC JI J. Chem. Educ. PD DEC PY 1998 VL 75 IS 12 BP 1520 EP 1520 PG 1 WC Chemistry, Multidisciplinary; Education, Scientific Disciplines SC Chemistry; Education & Educational Research GA 139PP UT WOS:000077038200006 ER PT J AU Pile, DL Benjamin, AS Lackner, KS Wendt, CH Butt, DP AF Pile, DL Benjamin, AS Lackner, KS Wendt, CH Butt, DP TI A precise method for determining the CO2 content of carbonate materials SO JOURNAL OF CHEMICAL EDUCATION LA English DT Article C1 Univ Calif Los Alamos Natl Lab, Mat Corros & Environm Effects Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. RP Butt, DP (reprint author), Univ Calif Los Alamos Natl Lab, Mat Corros & Environm Effects Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. RI Butt, Darryl/B-7480-2008 OI Butt, Darryl/0000-0003-4501-8864 NR 8 TC 3 Z9 3 U1 0 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0021-9584 J9 J CHEM EDUC JI J. Chem. Educ. PD DEC PY 1998 VL 75 IS 12 BP 1610 EP 1614 PG 5 WC Chemistry, Multidisciplinary; Education, Scientific Disciplines SC Chemistry; Education & Educational Research GA 139PP UT WOS:000077038200052 ER PT J AU Liu, B Lu, ZY Pan, BC Wang, CZ Ho, KM Shvartsburg, AA Jarrold, MF AF Liu, B Lu, ZY Pan, BC Wang, CZ Ho, KM Shvartsburg, AA Jarrold, MF TI Ionization of medium-sized silicon clusters and the geometries of the cations SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID LANGEVIN MOLECULAR-DYNAMICS; SMALL SI CLUSTERS; SMALL SEMICONDUCTOR CLUSTERS; ION MOBILITY MEASUREMENTS; INTERATOMIC FORCE-FIELDS; TIGHT-BINDING; EQUILIBRIUM STRUCTURES; ELECTRONIC-STRUCTURES; VIBRATIONAL-SPECTRA; PHOTOELECTRON-SPECTROSCOPY AB We have performed a systematic ground state geometry search for the singly charged Si-n cations in the medium-size range (n less than or equal to 20) using density functional theory in the local density approximation (LDA) and generalized gradient approximation (GGA). The structures resulting for n less than or equal to 18 generally follow the prolate ''stacked Si-9 tricapped trigonal prism'' pattern recently established for the lowest energy geometries of neutral silicon clusters in this size range. However, the global minima of Si-n and Si-n(+) for n = 6, 8, 11, 12, and 13 differ significantly in their details. For S-19 and Si-20 neutrals and cations, GGA renders the prolate stacks practically isoenergetic with the near-spherical structures that are global minima in LDA. The mobilities in He gas evaluated for all lowest energy Si-n(+) geometries using the trajectory method agree with the experiment, except for n=18 where the second lowest isomer fits the measurements. The effect of gradient corrections for either the neutral or cationic clusters is subtle, but their inclusion proves to be critical for obtaining agreement with the mobility measurements in the n=15-20 range. We have also determined ionization potentials for our Si-n neutral geometries and found that all experimental size-dependent trends are reproduced for n less than or equal to 19. This particularly supports our structural assignments for Si-9, Si-11, Si-12, and Si-17 neutrals. The good overall agreement between the measured and calculated properties supports the elucidation of the "prolate" family of silicon clusters as stacks of trigonal prisms. (C) 1998 American Institute of Physics. [S0021-9606(98)02445-3]. C1 Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. Northwestern Univ, Dept Chem, Evanston, IL 60208 USA. RP Iowa State Univ, Ames Lab, Ames, IA 50011 USA. RI 上官, 敏慧/E-8964-2012; Pan, Bicai/A-1235-2010; OI Pan, Bicai/0000-0002-5128-7860 NR 99 TC 159 Z9 163 U1 1 U2 15 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 0021-9606 EI 1089-7690 J9 J CHEM PHYS JI J. Chem. Phys. PD DEC 1 PY 1998 VL 109 IS 21 BP 9401 EP 9409 DI 10.1063/1.477601 PG 9 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 141MN UT WOS:000077147900022 ER PT J AU Sugama, T Hanwood, T AF Sugama, T Hanwood, T TI Polyacrylamide-grafted dextrine copolymer coatings SO JOURNAL OF COATINGS TECHNOLOGY LA English DT Article ID RAY PHOTOELECTRON-SPECTROSCOPY; POLYMER SURFACES; STARCH; POLYIMIDE; MECHANISM; ALUMINUM AB Polyacrylamide (PAM)-grafted dextrine (DEX) copolymers were prepared by heating a film-forming precursor solution consisting of PAM, corn starch-derived DEX, cerium (IV) nitrate hexahydrate, and water, at 150 degrees or 200 degrees C; these solutions were applied as water-based primer coating systems to aluminum (Al) substrates. Grafting PAM on the DEX not only inhibited the fragmentation of DEX structures caused by oxidation at 200 degrees C in air, but also aided in fabricating coating films that were less susceptible to moisture and minimized the rate of permeation of electrolyte species through the film layers. In addition, the grafted DEX coating films favorable reacted with the Al substrate to form Al-O bonds at interfaces. Consequently, Al panels coated with a highly grafted DEX copolymer had a salt-spray resistance of 600 hr. C1 Brookhaven Natl Lab, Dept Appl Sci, Energy Efficiency & Conservat Div, Upton, NY 11973 USA. RP Sugama, T (reprint author), Brookhaven Natl Lab, Dept Appl Sci, Energy Efficiency & Conservat Div, Upton, NY 11973 USA. NR 23 TC 2 Z9 2 U1 1 U2 1 PU FEDERATION SOC COATING TECH PI BLUE BELL PA 492 NORRISTOWN ROAD, BLUE BELL, PA 19422 USA SN 0361-8773 J9 J COATING TECHNOL JI J. Coat. Technol. PD DEC PY 1998 VL 70 IS 887 BP 69 EP 78 DI 10.1007/BF02700545 PG 10 WC Chemistry, Applied; Materials Science, Coatings & Films SC Chemistry; Materials Science GA 147TN UT WOS:000077514000010 ER PT J AU Vineis, CJ Wang, CA Jensen, KF Breiland, WG AF Vineis, CJ Wang, CA Jensen, KF Breiland, WG TI In situ monitoring of GaSb, GaInAsSb, and AlGaAsSb SO JOURNAL OF CRYSTAL GROWTH LA English DT Article; Proceedings Paper CT 9th International Conference on Metalorganic Vpour Phase Epitaxy (ICMOVPE-IX) CY MAY 31-JUN 04, 1998 CL LA JOLLA, CALIFORNIA DE GaInAsSb; AlGaAsSb; GaSb; in situ reflectance monitoring; organometallic vapor phase epitaxy; OMVPE ID CHEMICAL-VAPOR-DEPOSITION; LASER REFLECTANCE; GROWTH; EPITAXY; REFLECTOMETRY AB The suitability of the wavelength range provided by silicon photodiode detector arrays for monitoring the spectral reflectance during epitaxial growth of GaSb, AlGaAsSb, and GaInAsSb, which have cutoff wavelengths at 25 degrees C of 1.7, 1.2, and 2.3 mu m, respectively, is demonstrated. These alloys were grown lattice matched to GaSb in a vertical rotating-disk reactor, which was modified to accommodate near normal reflectance without affecting epilayer uniformity. By using a virtual interface model, the growth rate and complex refractive index at the growth temperature are extracted for these alloys over the 600-1000 nm spectral range. Excellent agreement is obtained between the extracted growth rate and that determined by ex situ measurement. (C) 1998 Published by Elsevier Science B.V. All rights reserved. C1 MIT, Lincoln Lab, Lexington, MA 02173 USA. MIT, Dept Mat Sci & Engn, Cambridge, MA 02139 USA. MIT, Dept Chem Engn, Cambridge, MA 02139 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Vineis, CJ (reprint author), MIT, Lincoln Lab, 244 Wood St, Lexington, MA 02173 USA. RI Jensen, Klavs/F-2462-2012 OI Jensen, Klavs/0000-0001-7192-580X NR 17 TC 12 Z9 12 U1 0 U2 7 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-0248 J9 J CRYST GROWTH JI J. Cryst. Growth PD DEC PY 1998 VL 195 IS 1-4 BP 181 EP 186 DI 10.1016/S0022-0248(98)00699-X PG 6 WC Crystallography; Materials Science, Multidisciplinary; Physics, Applied SC Crystallography; Materials Science; Physics GA 153NM UT WOS:000077839200030 ER PT J AU Hou, HQ Hammons, BE Breiland, WG AF Hou, HQ Hammons, BE Breiland, WG TI In situ etching of GaAs by AsCl3 for regrowth on AlGaAs in metalorganic vapor-phase epitaxy SO JOURNAL OF CRYSTAL GROWTH LA English DT Article; Proceedings Paper CT 9th International Conference on Metalorganic Vpour Phase Epitaxy (ICMOVPE-IX) CY MAY 31-JUN 04, 1998 CL LA JOLLA, CALIFORNIA DE in situ etching; AsCl3; selective etching; MOVPE AB In situ etching of GaAs with AsCl3 in metalorganic vapor-phase epitaxy (MOVPE) reactor was studied with in situ reflectometry as a function of the AsCl3 flow rate, substrate temperature, and AsH3 flow rate during etching. A smooth and uniform etched surface was successfully achieved at substrate temperatures above 680 degrees C. The etch rate was found to be proportional to the flow rate of AsCl3, and exhibited Arrhenius temperature dependence with an activation energy of similar to 1 eV. The etching was also found to be very selective towards the Al composition in AlGaAs, and stopped abruptly on AlGaAs. This process has applications for MOVPE regrowth on an AlGaAs surface after a selective in situ etch of the GaAs cap layer. (C) 1998 Published by Elsevier Science B.V. All rights reserved. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Hou, HQ (reprint author), EMCORE Corp, 10420 Res Rd SE, Albuquerque, NM 87123 USA. NR 9 TC 2 Z9 2 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-0248 J9 J CRYST GROWTH JI J. Cryst. Growth PD DEC PY 1998 VL 195 IS 1-4 BP 199 EP 204 DI 10.1016/S0022-0248(98)00733-7 PG 6 WC Crystallography; Materials Science, Multidisciplinary; Physics, Applied SC Crystallography; Materials Science; Physics GA 153NM UT WOS:000077839200033 ER PT J AU Han, J Figiel, JJ Crawford, MH Banas, MA Bartram, ME Biefeld, RM Song, YK Nurmikko, AV AF Han, J Figiel, JJ Crawford, MH Banas, MA Bartram, ME Biefeld, RM Song, YK Nurmikko, AV TI OMVPE growth and gas-phase reactions of AlGaN for UV emitters SO JOURNAL OF CRYSTAL GROWTH LA English DT Article; Proceedings Paper CT 9th International Conference on Metalorganic Vpour Phase Epitaxy (ICMOVPE-IX) CY MAY 31-JUN 04, 1998 CL LA JOLLA, CALIFORNIA DE gas-phase reactions; LED; GaN; quantum well; diode ID CHEMICAL-VAPOR-DEPOSITION; MOLECULAR-BEAM EPITAXY; EMISSION; MOVPE AB Gas-phase parasitic reactions among TMG, TMA, and NH3, are investigated by monitoring the growth rate/incorporation efficiency of GaN and AlN using an in situ optical reflectometer. It is suggested that gas phase adduct (TMA: NH3) reactions not only reduce the incorporation efficiency of TMA but also affect the incorporation behavior of TMGa. The observed phenomena can be explained by either a synergistic gas-phase scavenging effect or a surface site-blocking effect. Relatively low reactor pressures (30-50 Torr) are employed to grow an AlGaN/GaN QW p-n diode structure. The UV emission at 354 nm (FWHM similar to 6 nm) represents the first report of LED operation from an indium-free GaN QW diode. (C) 1998 Published by Elsevier Science B.V. All rights reserved. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Brown Univ, Div Engn, Providence, RI 02912 USA. RP Han, J (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 20 TC 53 Z9 55 U1 1 U2 16 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-0248 J9 J CRYST GROWTH JI J. Cryst. Growth PD DEC PY 1998 VL 195 IS 1-4 BP 291 EP 296 DI 10.1016/S0022-0248(98)00675-7 PG 6 WC Crystallography; Materials Science, Multidisciplinary; Physics, Applied SC Crystallography; Materials Science; Physics GA 153NM UT WOS:000077839200049 ER PT J AU Dupuis, RD Park, J Grudowski, PA Eiting, CJ Liliental-Weber, Z AF Dupuis, RD Park, J Grudowski, PA Eiting, CJ Liliental-Weber, Z TI Selective-area and lateral epitaxial overgrowth of III-N materials by metalorganic chemical vapor deposition SO JOURNAL OF CRYSTAL GROWTH LA English DT Article; Proceedings Paper CT 9th International Conference on Metalorganic Vpour Phase Epitaxy (ICMOVPE-IX) CY MAY 31-JUN 04, 1998 CL LA JOLLA, CALIFORNIA ID PHASE EPITAXY; GAN; SAPPHIRE; GROWTH; LAYERS AB We describe the characteristics of single-crystal GaN regions obtained by selective-art a and subsequent lateral epitaxial overgrowth using metalorganic chemical vapor deposition. For a range of deposition conditions, the surface kinetics of the metalorganic chemical vapor deposition process results in an initial stage of selective-area growth, subsequently followed by the lateral growth of single-crystal GaN over the SiO2 mask. The lateral-to-vertical relative growth rate depends upon the orientation of stripe openings with respect to the GaN crystal planes, the ratio of the "open" stripe width to the "masked" stripe width, and the specific growth conditions (e.g., temperature and V/III ratio). The crystalline orientations of the growth facets on the sidewalls of the laterally growing stripes are also dependent upon the growth conditions. The results of cathodoluminescence and transmission-electron microscopy studies of the GaN films indicate that materials with improved quality are grown over the oxide mask. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Univ Texas, Microelect Res Ctr, Austin, TX 78712 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Dupuis, RD (reprint author), Univ Texas, Microelect Res Ctr, PRC MER 1-606D-R9900, Austin, TX 78712 USA. RI Liliental-Weber, Zuzanna/H-8006-2012 NR 13 TC 13 Z9 13 U1 0 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-0248 J9 J CRYST GROWTH JI J. Cryst. Growth PD DEC PY 1998 VL 195 IS 1-4 BP 340 EP 345 DI 10.1016/S0022-0248(98)00674-5 PG 6 WC Crystallography; Materials Science, Multidisciplinary; Physics, Applied SC Crystallography; Materials Science; Physics GA 153NM UT WOS:000077839200058 ER PT J AU Biefeld, RM Allerman, AA Kurtz, SR Baucom, KC AF Biefeld, RM Allerman, AA Kurtz, SR Baucom, KC TI Progress in the growth of mid-infrared InAsSb emitters by metal-organic chemical vapor deposition SO JOURNAL OF CRYSTAL GROWTH LA English DT Article; Proceedings Paper CT 9th International Conference on Metalorganic Vpour Phase Epitaxy (ICMOVPE-IX) CY MAY 31-JUN 04, 1998 CL LA JOLLA, CALIFORNIA DE InAsSb IR emitters; mid-infrared lasers; MOCVD; multi-stage lasers ID INTERBAND CASCADE LASERS; LIGHT-EMITTING-DIODES; MIDINFRARED LASERS; QUANTUM-WELLS; MU-M; ALASSB AB We report on recent progress and improvements in the metal-organic chemical vapor deposition (MOCVD) of mid-infrared InAsSb emitters using a high speed rotating disk reactor (RDR). The devices contain AlAsSb claddings and strained InAsSb active regions. These emitters have multi-stage, type I, InAsSb/lnAsP quantum well active regions. A semi-metal GaAsSb/InAs layer acts as an internal electron source for the multi-stage injection lasers and AlAsSb is the electron confinement layer. These structures are the first MOCVD multi-stage devices. Growth in an RDR was necessary to avoid the previously observed Al memory effects found in a horizontal reactor. Broadband LEDs produced 2 mW average power at 3.7 mu m and 80 K and 0.1 mW at 4.3 mu m and 300 K. A multi-stage, 3.8-3.9 mu m laser structure operated up to T = 180 K. At 80 K, peak-power > 100 mW/facet and a high slope-efficiency (48%) were observed in these gain guided lasers. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Biefeld, RM (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 12 TC 13 Z9 13 U1 1 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-0248 J9 J CRYST GROWTH JI J. Cryst. Growth PD DEC PY 1998 VL 195 IS 1-4 BP 356 EP 362 DI 10.1016/S0022-0248(98)00643-5 PG 7 WC Crystallography; Materials Science, Multidisciplinary; Physics, Applied SC Crystallography; Materials Science; Physics GA 153NM UT WOS:000077839200060 ER PT J AU Geisz, JF Friedman, DJ Olson, JM Kurtz, SR Keyes, BM AF Geisz, JF Friedman, DJ Olson, JM Kurtz, SR Keyes, BM TI Photocurrent of 1 eV GaInNAs lattice-matched to GaAs SO JOURNAL OF CRYSTAL GROWTH LA English DT Article; Proceedings Paper CT 9th International Conference on Metalorganic Vpour Phase Epitaxy (ICMOVPE-IX) CY MAY 31-JUN 04, 1998 CL LA JOLLA, CALIFORNIA DE GaInNAs; dimethylhydrazine; quantum efficiency; MOVPE; diffusion length; Hall mobility; absorption coefficient; annealing ID CARBON-DOPED GAAS; HIGH-TEMPERATURE PERFORMANCE; CHEMICAL-VAPOR-DEPOSITION; LASER-DIODES; PASSIVATION; GROWTH; OPERATION; GAP AB The spectral photocurrent response, or quantum efficiency, of GaInNAs lattice-matched to GaAs with a bandgap of 1 eV has been measured in an electrochemical cell in order to optimize material quality for use in a multijunction solar cell lattice-matched to GaAs or Ge. GaInNAs with about 3% nitrogen grown by MOVPE using dimethylhydrazine as a nitrogen source was found to be p-type with hole concentrations of about 1 x 10(17) cm(-3), possibly due to unintentional carbon doping as observed by SIMS. This unintentionally doped material typically had up to 20% internal quantum efficiencies and an absorption coefficient of about 10000 cm(-1), 200 meV above the bandedge. By doping the material with Si, Se, or Zn, we find that the quantum efficiency is strongly correlated with the carrier concentration because the quantum efficiency is limited by the junction depletion width rather than the bulk minority carrier diffusion length. Low minority carrier lifetimes and mobilities both appear to contribute to these short diffusion lengths. We have observed significant increases in temperature dependent Hall mobilities and photoluminescence intensities due to changes in growth conditions and post-growth anneals. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Geisz, JF (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 18 TC 242 Z9 244 U1 1 U2 33 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-0248 J9 J CRYST GROWTH JI J. Cryst. Growth PD DEC PY 1998 VL 195 IS 1-4 BP 401 EP 408 DI 10.1016/S0022-0248(98)00563-6 PG 8 WC Crystallography; Materials Science, Multidisciplinary; Physics, Applied SC Crystallography; Materials Science; Physics GA 153NM UT WOS:000077839200067 ER PT J AU Friedman, DJ Geisz, JF Kurtz, SR Olson, JM AF Friedman, DJ Geisz, JF Kurtz, SR Olson, JM TI 1-eV solar cells with GaInNAs active layer SO JOURNAL OF CRYSTAL GROWTH LA English DT Article; Proceedings Paper CT 9th International Conference on Metalorganic apour Phase Epitaxy (ICMOVPE-IX) CY MAY 31-JUN 04, 1998 CL LA JOLLA, CA DE solar cells; diffusion length; MOVPE; GaInNAs; GaInAsN; dimethylhydrazine ID ALLOYS; GAASN AB We demonstrate working prototypes of a GaInNAs-based solar cell lattice-matched to GaAs with photoresponse down to 1 eV. This device is intended for use as the third junction of future-generation ultrahigh-efficiency three- and four-junction devices. Under the AM1.5 direct spectrum with all the light higher in energy than the GaAs band gap filtered out, the prototypes have open-circuit voltages ranging from 0.35 to 0.44 V, short-circuit currents of 1.8 mA/cm(2), and fill factors from 61% to 66%. The short-circuit currents are of principal concern: the internal quantum efficiencies rise only to about 0.2. We discuss the short diffusion lengths which are the reason for this low photocurrent. As a partial workaround for the poor diffusion lengths, we demonstrate a depletion-width-enhanced variation of one of the prototype devices that trades off decreased voltage for increased photocurrent, with a short-circuit current of 6.5 mA/cm(2) and an open-circuit voltage of 0.29 V. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Friedman, DJ (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. EM friedman@nrel.gov NR 10 TC 329 Z9 334 U1 2 U2 33 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-0248 J9 J CRYST GROWTH JI J. Cryst. Growth PD DEC PY 1998 VL 195 IS 1-4 BP 409 EP 415 DI 10.1016/S0022-0248(98)00561-2 PG 7 WC Crystallography; Materials Science, Multidisciplinary; Physics, Applied SC Crystallography; Materials Science; Physics GA 153NM UT WOS:000077839200068 ER PT J AU Friedman, DJ Geisz, JF Kurtz, SR Olson, JM Reedy, R AF Friedman, DJ Geisz, JF Kurtz, SR Olson, JM Reedy, R TI Nonlinear dependence of N incorporation on In content in GaInNAs SO JOURNAL OF CRYSTAL GROWTH LA English DT Article; Proceedings Paper CT 9th International Conference on Metalorganic Vpour Phase Epitaxy (ICMOVPE-IX) CY MAY 31-JUN 04, 1998 CL LA JOLLA, CALIFORNIA DE MOVPE; GaInNAs; GaInAsN; dimethylhydrazine; N incorporation ID MOLECULAR-BEAM EPITAXY; CHEMICAL-VAPOR-DEPOSITION; LASER-DIODES; GROWTH; NITROGEN; SEMICONDUCTORS; SOLUBILITY; ALLOYS; GAASN AB Ga1-xInxNyAs1-y with a few percent In and N has recently been demonstrated as a 1 eV material lattice-matched to GaAs. Similarly, it is expected that for Ga0.5-xIn0.5+xNyAs1-y, which is lattice-matched to InP, band gaps from similar to 0.7-0.3 eV should be achievable if a few percent N could be incorporated. I Here, we compare the growth of GaInNAs/InP with GaInNAs/GaAs. Epilayers of both alloy compositions were grown under comparable conditions by metal-organic vapor-phase epitaxy (MOVPE) with dimethylhydrazine. For GaInNAs/GaAs, nitrogen concentrations as high as 3% were measured, with corresponding bandgaps down to 0.96 eV. In contrast, for GaInNAs/InP, secondary ion mass spectroscopy (SIMS) measurements show a N concentration at least 100 times smaller in GaInNAs/InP than in GaInNAs/GaAs at comparable growth conditions, and, consistent with this observation, no bandgap depression is seen. Thus, N incorporation in GaInNAs falls off superlinearly with In concentration. Possible reasons for this are discussed. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Friedman, DJ (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 22 TC 68 Z9 69 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-0248 J9 J CRYST GROWTH JI J. Cryst. Growth PD DEC PY 1998 VL 195 IS 1-4 BP 438 EP 443 DI 10.1016/S0022-0248(98)00562-4 PG 6 WC Crystallography; Materials Science, Multidisciplinary; Physics, Applied SC Crystallography; Materials Science; Physics GA 153NM UT WOS:000077839200072 ER PT J AU Potter, BG Sinclair, MB AF Potter, BG Sinclair, MB TI Photosensitive and rare-earth doped ceramics for optical sensing: A review SO JOURNAL OF ELECTROCERAMICS LA English DT Article DE photo sensitivity; rare-earth; ceramics; optical sensors ID PLANAR WAVE-GUIDES; TRANSVERSE HOLOGRAPHIC METHOD; BRAGG GRATING INSCRIPTION; UV WRITTEN GRATINGS; GERMANOSILICATE GLASS; SENSOR APPLICATIONS; FIBER GRATINGS; FLUORIDE FIBER; SILICA FIBER; TEMPERATURE AB This work reviews two inorganic materials classes used for optical sensors: photosensitive glasses and rare-earth doped materials. The underlying physical mechanisms contributing to the photosensitive response of germanosilicate glasses are discussed, along with a summary of optical sensor strategies which have been developed based upon photo-imprinted Bragg gratings. Particular attention is paid to the fabrication and characterization of photosensitive germanosilicate thin-films. Insights into the ability to control the photosensitivity of these materials through manipulation of material compositions and structures are also included. The discussion of rare-earth doped optical sensor materials emphasizes the important contribution of the host material to the observed optical behavior of the rare-earth ions. The use of rare-earth doped materials in applications ranging from temperature sensing to fiber-optic gyroscopes is also described. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Potter, BG (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 67 TC 11 Z9 11 U1 0 U2 8 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 1385-3449 J9 J ELECTROCERAM JI J. Electroceram. PD DEC PY 1998 VL 2 IS 4 BP 295 EP 308 DI 10.1023/A:1009982708530 PG 14 WC Materials Science, Ceramics SC Materials Science GA 164YR UT WOS:000078491600008 ER PT J AU Cheung, YS Hsu, CW Ng, CY AF Cheung, YS Hsu, CW Ng, CY TI Non-resonant two photon pulsed field ionization photoelectron study of CH3CH2S formed in the photodissociation of CH3CH2SH SO JOURNAL OF ELECTRON SPECTROSCOPY AND RELATED PHENOMENA LA English DT Article DE N2P-PFI-PE; CH3CH2SH; ab initio ID C2H5S AB The non-resonant two-photon pulsed field ionization photoelectron (N2P-PFI-PE) spectrum for CH3CH2S produced in the photodissociation of CH3CH2SH has been measured in the energy region of 2 x (36 160-37 200) cm(-1). The assignment of the N2P-PFI-PE spectrum indicates that both the (X) over tilde 2A " and (A) over tilde 2A' states for CH3CH2S are formed in the photodissociation of CH3CH2SH at h nu approximate to 4.6 eV. The ionization energies for transitions to CH3CH2S+ ((X) over tilde(3)A ") from the (X) over tilde(2)A " and (A) over tilde(2)A' states of CH3CH2S are determined to be 9.107 +/- 0.003 and 9.077 +/- 0.004 eV, respectively. The small energy gap of 0.030 +/- 0.004 eV observed between the (X) over tilde(2)A " and (A) over tilde(2)A' states of CH3CH2S is consistent with the ab initio theoretical calculation. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Iowa State Univ, US DOE, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Chem, Ames, IA 50011 USA. RP Ng, CY (reprint author), Iowa State Univ, US DOE, Ames Lab, Ames, IA 50011 USA. NR 12 TC 10 Z9 11 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0368-2048 J9 J ELECTRON SPECTROSC JI J. Electron Spectrosc. Relat. Phenom. PD DEC PY 1998 VL 97 IS 1-2 BP 115 EP 120 DI 10.1016/S0368-2048(98)00262-X PG 6 WC Spectroscopy SC Spectroscopy GA 162TE UT WOS:000078362200011 ER PT J AU Litorja, M Ruscic, B AF Litorja, M Ruscic, B TI A photoionization study of the hydroperoxyl radical, HO2, and hydrogen peroxide, H2O2 SO JOURNAL OF ELECTRON SPECTROSCOPY AND RELATED PHENOMENA LA English DT Article DE hydrogen peroxide; hydroperoxyl radical; photoionization mass spectrometry; enthalpy of formation; appearance energy; bond dissociation energy; ionization energy ID BOND-DISSOCIATION ENERGIES; PHOTOELECTRON-SPECTROSCOPY; REDOX POTENTIALS; THEORETICAL CHARACTERIZATION; TEMPERATURE-DEPENDENCE; BRANCHING RATIO; DELTA-HDBE; GAS-PHASE; H-OO; HEAT AB Hydrogen peroxide and the hydroperoxyl radical have been studied by photoionization mass spectrometry. The radical has been produced in situ from H2O2 by hydrogen abstraction with fluorine atoms produced in a microwave discharge. The adiabatic ionization energy of the hydroperoxyl radical has been measured as IE(HO2) = 11.352 +/- 0.007 eV, while that of hydrogen peroxide has been determined to be IE(H2O2) = 10.631 +/- 0.007 eV. The OH+ and HO2+ fragments from H2O2 were also measured and their threshold behavior was analyzed in terms of model functions. The 0 K appearance energy of the HO2+ fragment was determined to be AE(0)(HO2+/H2O2) = 15.112 +/- 0.035 eV. From these values, the O-H bond dissociation energy in hydrogen peroxide of D-0(H-OOH) = 86.7 +/- 0.8 kcal mol(-1) (87.9 +/- 0.8 kcal mol(-1) at 298 K) was determined, yielding the enthalpy of formation of the hydroperoxyl radical of Delta H-f0(-)(HO2) = 4.0 +/- 0.8 kcal mol(-1) (3.3 +/- 0.8 kcal mol(-1) at 298 K), and also implying the proton affinity of oxygen of PA(O-2) = 100.6 +/- 0.8 kcal mol(-1) and the enthalpy of deprotonation of hydrogen peroxide of Delta H-acid (-)(298)(H2O2) = 376.4 +/- 0.8 kcal mol(-1). (C) 1998 Elsevier Science B.V. All rights reserved. C1 Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. RP Ruscic, B (reprint author), Argonne Natl Lab, Div Chem, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Ruscic, Branko/A-8716-2008 OI Ruscic, Branko/0000-0002-4372-6990 NR 84 TC 71 Z9 71 U1 1 U2 25 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0368-2048 J9 J ELECTRON SPECTROSC JI J. Electron Spectrosc. Relat. Phenom. PD DEC PY 1998 VL 97 IS 1-2 BP 131 EP 146 DI 10.1016/S0368-2048(98)00264-3 PG 16 WC Spectroscopy SC Spectroscopy GA 162TE UT WOS:000078362200013 ER PT J AU Ravindra, NM Gokce, OH Sopori, BL AF Ravindra, NM Gokce, OH Sopori, BL TI Special section on transient thermal processing of electronic materials - Foreword SO JOURNAL OF ELECTRONIC MATERIALS LA English DT Editorial Material C1 New Jersey Inst Technol, Newark, NJ 07102 USA. Natl Renewable Energy Lab, Golden, CO USA. RP Ravindra, NM (reprint author), New Jersey Inst Technol, Newark, NJ 07102 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 USA SN 0361-5235 J9 J ELECTRON MATER JI J. Electron. Mater. PD DEC PY 1998 VL 27 IS 12 BP 1277 EP 1277 DI 10.1007/s11664-998-0085-4 PG 1 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Physics, Applied SC Engineering; Materials Science; Physics GA 146PW UT WOS:000077440400001 ER PT J AU Moore, HJ Olson, DL Noufi, R AF Moore, HJ Olson, DL Noufi, R TI Use of the effective heat of formation model to determine phase formation sequences of In-Se, Ga-Se, Cu-Se, and Ga-In multilayer thin films SO JOURNAL OF ELECTRONIC MATERIALS LA English DT Article; Proceedings Paper CT 2nd Conference on Transient Thermal Processing CY FEB, 1998 CL SAN ANTONIO, TEXAS SP TMS, Electr Magnet & Photon Mat Div DE differential thermal analysis (DTA); effective heat of formation; solar cells; thin films; x-ray diffraction (XRD) AB Multilayer thin films of indium-selenium, gallium-selenium, copper-selenium, and gallium-indium have been analyzed for the purpose of understanding thin film phase transformations that are relevant to the production of Cu(In,Ga)Se photovoltaic solar cells. For example, the intermetallic phases that are present during selenization of precursor films will affect film microstructure and the resulting film properties. Throughout this research, the effective heat of formation model(1) has been used to predict phase formation sequences. The accuracy of these predictions was explored experimentally. By using differential thermal analysis, the reactions of product film formation were examined. X-ray diffraction was used to determine reactant and product phases. C1 Colorado Sch Mines, Dept Met & Mat Engn, Golden, CO 80401 USA. Natl Renewable Energy Lab, Solar Energy Res Facil, Golden, CO USA. RP Moore, HJ (reprint author), Colorado Sch Mines, Dept Met & Mat Engn, Golden, CO 80401 USA. NR 7 TC 11 Z9 11 U1 0 U2 2 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 USA SN 0361-5235 J9 J ELECTRON MATER JI J. Electron. Mater. PD DEC PY 1998 VL 27 IS 12 BP 1334 EP 1340 DI 10.1007/s11664-998-0093-4 PG 7 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Physics, Applied SC Engineering; Materials Science; Physics GA 146PW UT WOS:000077440400009 ER PT J AU Sopori, BL Chen, W Abedrabbo, S Ravindra, NM AF Sopori, BL Chen, W Abedrabbo, S Ravindra, NM TI Modeling emissivity of rough and textured silicon wafers SO JOURNAL OF ELECTRONIC MATERIALS LA English DT Article; Proceedings Paper CT 2nd Conference on Transient Thermal Processing CY FEB, 1998 CL SAN ANTONIO, TEXAS SP TMS, Electr Magnet & Photon Mat Div DE absorption coefficient; emissivity; refractive index; silicon wafers; surface roughness ID ELEVATED-TEMPERATURES AB A method for calculating the emissivity of Si wafers with planar and nonplanar (such as rough or textured) surface morphologies is described. The technique is similar to that used in modeling of light trapping in solar cells and is also applicable to those cases when the wafer may have thin dielectric or metal layers. A software package is developed that uses this method. This package includes an approach for calculating the refractive index and absorption coefficient as a function of wavelength, for various temperatures and dopant concentrations. We present results for a number of cases to demonstrate the applications of this model. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. New Jersey Inst Technol, Newark, NJ 07102 USA. RP Sopori, BL (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 13 TC 4 Z9 4 U1 1 U2 7 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 USA SN 0361-5235 J9 J ELECTRON MATER JI J. Electron. Mater. PD DEC PY 1998 VL 27 IS 12 BP 1341 EP 1346 DI 10.1007/s11664-998-0094-3 PG 6 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Physics, Applied SC Engineering; Materials Science; Physics GA 146PW UT WOS:000077440400010 ER PT J AU Von Dreele, RB Morgan, JG Stishov, SM AF Von Dreele, RB Morgan, JG Stishov, SM TI Thermal expansion and equation for state of KCN of different isotopic composition SO JOURNAL OF EXPERIMENTAL AND THEORETICAL PHYSICS LA English DT Article ID POTASSIUM CYANIDE; NEUTRON-DIFFRACTION AB Thermal expansion and the equation of state of isotopically different samples of KCN were measured in the temperature range 175-300 K and at pressures up to 2 GPa by the neutron powder diffraction technique. No evidence of the influence of isotopic composition on the thermal expansion or the compression isotherms was found. (C) 1998 American Institute of Physics. [S1063-7761(98)02112-X]. C1 Univ Calif Los Alamos Natl Lab, Lujan Ctr, Los Alamos, NM 87545 USA. Russian Acad Sci, Inst High Pressure Phys, Troitsk 142092, Moscow Region, Russia. RP Stishov, SM (reprint author), Univ Calif Los Alamos Natl Lab, Lujan Ctr, MS H805, Los Alamos, NM 87545 USA. EM sergei@hppi.troitsk.ru NR 12 TC 2 Z9 2 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1063-7761 J9 J EXP THEOR PHYS+ JI J. Exp. Theor. Phys. PD DEC PY 1998 VL 87 IS 6 BP 1188 EP 1190 PG 3 WC Physics, Multidisciplinary SC Physics GA 153ED UT WOS:000077819400021 ER PT J AU Vorobieff, P Ecke, RE AF Vorobieff, P Ecke, RE TI Flow structure in a Rayleigh-Benard cell upon impulsive spin-up SO JOURNAL OF FLUIDS ENGINEERING-TRANSACTIONS OF THE ASME LA English DT Article ID NUMBER CONVECTION; ROTATING FLUID AB We investigate convection in a cylindrical Rayleigh-Benard cell with radius-to-height ratio Gamma = 1/2. The cell is subjected to impulsive spin-up about its vertical axis. We use TLC (thermochromic liquid crystal) imaging for temperature field measurements and PIV (particle image velocimetry) for velocity reconstruction of the transition in the range of Rayleigh numbers R from 5 X 10(7) to 5 X 10(8) and dimensionless rotation rates Omega from 0 up to 8 X 10(4). The initial (at rest) and the final (in steady rotation) states of the system are those of turbulent convection. The most persistent transient feature is a well-defined ring pattern characterized by a decrease in temperature, axial velocity directed downward and high azimuthal shear. The latter leads to formation of an azimuthally regular structure of Kelvin-Helmholz vortices. During the final stage of the transition, this vortical structure loses azimuthal regularity and an irregular pattern of vortices characteristic of turbulent rotating convection forms. C1 Univ Calif Los Alamos Natl Lab, Ctr Nonlinear Studies, Los Alamos, NM 87545 USA. Univ Calif Los Alamos Natl Lab, Condensed Matter & Thermal Phys Grp, Los Alamos, NM 87545 USA. RP Vorobieff, P (reprint author), Univ Calif Los Alamos Natl Lab, Ctr Nonlinear Studies, Los Alamos, NM 87545 USA. RI Vorobieff, Peter/B-3376-2011; OI Vorobieff, Peter/0000-0003-0631-7263; Ecke, Robert/0000-0001-7772-5876 NR 14 TC 0 Z9 0 U1 0 U2 2 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0098-2202 J9 J FLUID ENG-T ASME JI J. Fluids Eng.-Trans. ASME PD DEC PY 1998 VL 120 IS 4 BP 672 EP 675 DI 10.1115/1.2820721 PG 4 WC Engineering, Mechanical SC Engineering GA 151ZB UT WOS:000077749700006 ER PT J AU Faulques, E Wery, J Dulieu, B Seybert, C Perry, DL AF Faulques, E Wery, J Dulieu, B Seybert, C Perry, DL TI Synthesis, fabrication, and photoluminescence of CaF2 doped with rare earth ions SO JOURNAL OF FLUORESCENCE LA English DT Article; Proceedings Paper CT 24th Annual Conference of the Federation of Analytical Chemistry and Spectroscopy Societies (FACSS) CY OCT 29-30, 1997 CL PROVIDENCE, RI SP Akzo Nobel, Edinburgh Instruments, Photon Technol Int DE photoluminescence; europium; erbium; calcium fluoride; Raman spectroscopy ID RAMAN AB Ambient condition wet synthetic techniques were used to synthesize CaF2 doped with europium and erbium. Photoluminescence spectroscopy and energy-dispersive x-ray analyses were used to study the electronic states of rare earth (RE) ions and the degree of heterogeneity/homogeneity in the matrix. Raman spectroscopy was used to study the degree of crystallinity of CaF2. Effects on the photoluminescence spectra were studied as a function of the thermal treatment of CaF2 samples. C1 Univ Nantes, Lab Phys Cristalline, UMR CNRS 6502, Inst Mat Nantes, F-44322 Nantes 03, France. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Faulques, E (reprint author), Univ Nantes, Lab Phys Cristalline, UMR CNRS 6502, Inst Mat Nantes, BP 32229, F-44322 Nantes 03, France. NR 13 TC 7 Z9 8 U1 0 U2 14 PU SPRINGER/PLENUM PUBLISHERS PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1053-0509 J9 J FLUORESC JI J. Fluoresc. PD DEC PY 1998 VL 8 IS 4 BP 283 EP 287 DI 10.1023/A:1020556028008 PG 5 WC Biochemical Research Methods; Chemistry, Analytical; Chemistry, Physical SC Biochemistry & Molecular Biology; Chemistry GA 242DM UT WOS:000082923000002 ER PT J AU Dean, SO Callen, JD Furth, HP Clarke, JF Ohkawa, T Rutherford, PH AF Dean, SO Callen, JD Furth, HP Clarke, JF Ohkawa, T Rutherford, PH TI Status and objectives of tokamak systems for fusion research SO JOURNAL OF FUSION ENERGY LA English DT Review DE fusion; tokamak AB This report had its beginnings at the Third International Symposium on Toroidal Plasma Confinement held in Garching/Munich, Federal Republic of Germany, March 26-30, 1973. The American scientists who attended this conference agreed to assist in preparing a summary of the status of the field. Since that time, the authors of this report have had the opportunity to incorporate progress reported at the VI European Conference on Plasma Physics and Controlled Fusion, held in Moscow, U.S.S.R., from July 29 to August 3, 1973. The report has been available previously only as U.S. Atomic Energy Commission Report WASH-1295 (1974). It was the first comprehensive survey of the status of the tokamak fusion research concept, which was to become the cornerstone of the world fusion effort far the next quarter century. It provided the basis for the rapid buildup of the U.S. tokamak program during the latter half of the 1970's and is published now to archive its historical significance. C1 Fus Power Associates, Gaithersburg, MD 20879 USA. Univ Wisconsin, Madison, WI 53706 USA. Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. Battelle Pacific NW Lab, Washington, DC USA. Archimedes Technol Inc, La Jolla, CA USA. RP Dean, SO (reprint author), Fus Power Associates, 2 Profess Dr,Suite 249, Gaithersburg, MD 20879 USA. NR 270 TC 1 Z9 1 U1 2 U2 2 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0164-0313 EI 1572-9591 J9 J FUSION ENERG JI J. Fusion Energy PD DEC PY 1998 VL 17 IS 4 BP 289 EP 337 DI 10.1023/A:1021868025903 PG 49 WC Nuclear Science & Technology SC Nuclear Science & Technology GA V2728 UT WOS:000168669800002 ER PT J AU Su, YJ Horwitz, JL Moore, TE Giles, BL Chandler, MO Craven, PD Hirahara, M Pollock, CJ AF Su, YJ Horwitz, JL Moore, TE Giles, BL Chandler, MO Craven, PD Hirahara, M Pollock, CJ TI Polar wind survey with the Thermal Ion Dynamics Experiment Plasma Source Instrument suite aboard POLAR SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID ELECTRON-TEMPERATURE ANISOTROPY; RETURN CURRENT REGION; SUPRATHERMAL O+ IONS; TOPSIDE IONOSPHERE; KINETIC-MODEL; CENTRIFUGAL ACCELERATION; TRANSPORT MODELS; MAGNETOSPHERE; CAP; OUTFLOW AB In February 1996, the POLAR spacecraft was placed in an elliptical orbit with a 9 R-E geocentric distance apogee in the northern hemisphere and 1.8 R-E perigee in the southern hemisphere. The Thermal Ion Dynamics Experiment (TIDE) on POLAR has allowed sampling of the three-dimensional ion distribution functions with excellent energy, angular, and mass resolution. The Plasma Source Instrument (PSI), when operated, allows sufficient diminution of the electric potential to observe the polar wind at very high altitudes. In this paper, we describe the results of a survey of the polar wind characteristics for H+, He+, and O+ as observed by TIDE at similar to 5000 km and similar to 8 R-E altitudes over the polar cap during April-May 1996. At 5000 km altitude, the H+ polar wind exhibits a supersonic outflow, while O+ shows subsonic downflow, which suggests a cleft ion fountain origin for the O+ ions in the polar cap region. Dramatic decreases of the 5000 km altitude H+ and O+ ion densities and fluxes are seen as the solar zenith angle increases from 90 degrees to 100 degrees for the ionospheric base, which is consistent with solar illumination ionization control. However, the polar cap downward O+ flow and density decline from dayside to nightside in magnetic coordinates suggest a cleft ion fountain origin for the polar cap O+. Cleft ion fountain origin O+ density plumes could also be partially responsible for a similar day-night asymmetry in H+ owing to the charge-exchange reaction. At 8 R-E altitude, both H+ and O+ outflows are supersonic and H+ is the highly dominant ion species. The average bulk ion field-aligned velocities are in the typical ratio VO+ : VHe+: VH+ similar to 2 : 3 : 5, which may suggest a tendency toward comparable energy gains, such as via an electric potential layer. C1 NASA, George C Marshall Space Flight Ctr, Space Sci Lab, Huntsville, AL 35812 USA. NASA, Goddard Space Flight Ctr, Extraterr Phys Lab, Greenbelt, MD 20771 USA. Rikkyo Univ, Dept Phys, Tokyo 171, Japan. Univ Alabama, Ctr Space Plasma & Aeron Res, Huntsville, AL 35899 USA. SW Res Inst, Instrumentat & Space Res Div, San Antonio, TX 78238 USA. RP Chandler, MO (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. RI Moore, Thomas/D-4675-2012 OI Moore, Thomas/0000-0002-3150-1137 NR 78 TC 51 Z9 51 U1 1 U2 4 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD DEC 1 PY 1998 VL 103 IS A12 BP 29305 EP 29337 DI 10.1029/98JA02662 PG 33 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 149MD UT WOS:000077608400016 ER PT J AU Daughton, W AF Daughton, W TI Kinetic theory of the drift kink instability in a current sheet SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID THIN CURRENT SHEETS; NEUTRAL SHEET; PLASMA SHEET; MAGNETOTAIL; SUBSTORMS; MODE AB The linear stability of a current sheet is of interest in connection with the dynamics of the magnetotail and in particular as a triggering mechanism for substorms. Until recently, most theoretical work in this area has concentrated on the collisionless tearing mode. Recent simulations suggest that for thin current sheets another long wavelength electromagnetic mode, these-called drift kink instability, may also be of importance. The linear stability analysis for a Harris-type equilibrium is formulated using a kinetic description for both ions and electrons. The orbit integrals are treated numerically using the exact unperturbed particle orbits and including the global structure of the perturbation inside the integral. It is found that the drift kink has a significant electrostatic component which strongly alters the mode structure and real frequency relative to the case of a purely electromagnetic mode. The resulting growth rates, mode structure and parametric dependences are presented and compared with previous results. The effect of finite parallel wavelength is considered, and the relevance of the drift kink mode to the magnetotail is discussed. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Daughton, W (reprint author), Univ Calif Los Alamos Natl Lab, MS D466, Los Alamos, NM 87545 USA. RI Daughton, William/L-9661-2013 NR 32 TC 76 Z9 76 U1 0 U2 10 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD DEC 1 PY 1998 VL 103 IS A12 BP 29429 EP 29443 DI 10.1029/1998JA900028 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 149MD UT WOS:000077608400025 ER PT J AU Barbieri, R Hall, LJ Smith, D Weiner, NJ Strumia, A AF Barbieri, R Hall, LJ Smith, D Weiner, NJ Strumia, A TI Oscillations of solar and atmospheric neutrinos SO JOURNAL OF HIGH ENERGY PHYSICS LA English DT Article DE solar and atmospheric neutrinos; beyond Standard Model; neutrino physics ID MATTER; FLUX AB Motivated by recent results from SuperKamiokande, we study both solar and atmospheric neutrino fluxes in the context of oscillations of the three known neutrinos. We aim at a global view which identifies the various possibilities, rather than attempting the most accurate determination of the parameters of each scenario. For solar neutrinos we emphasise the importance of performing a general analysis, independent of any particular solar model and we consider the possibility that any one of the techniques - chlorine, gallium or water Cerenkov - has a large unknown systematic error, so that its results should be discarded. The atmospheric neutrino anomaly is studied by paying special attention to the ratios of upward and downward going nu(e) and nu(mu) fluxes. Both anomalies can be described in a minimal scheme where the respective oscillation frequencies are widely separated or in non-minimal schemes with two comparable oscillation frequencies. We discuss explicit forms of neutrino mass matrices in which both atmospheric and solar neutrino fluxes are explained. In the minimal scheme we identify only two 'zeroth order' textures that can result from unbroken symmetries. Finally we discuss experimental strategies for the determination of the various oscillation parameters. C1 Scuola Normale Super Pisa, I-56126 Pisa, Italy. Ist Nazl Fis Nucl, Sez Pisa, I-56126 Pisa, Italy. Univ Calif Berkeley, Lawrence Berkeley Lab, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Theoret Phys Grp, Berkeley, CA 94720 USA. Univ Pisa, Dipartimento Fis, I-56127 Pisa, Italy. Ist Nazl Fis Nucl, Sez Pisa, I-56127 Pisa, Italy. RP Scuola Normale Super Pisa, Piazza Cavalieri 7, I-56126 Pisa, Italy. EM barbieri@difi.unipi.it; LJHall@lbl.gov; NJWeiner@lbl.gov; astrumia@difi.unipi.it NR 43 TC 181 Z9 181 U1 0 U2 0 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1029-8479 J9 J HIGH ENERGY PHYS JI J. High Energy Phys. PD DEC PY 1998 IS 12 AR 017 PG 31 WC Physics, Particles & Fields SC Physics GA 200CU UT WOS:000080522700017 ER PT J AU de Boer, J Ooguri, H Robins, H Tannenhauser, J AF de Boer, J Ooguri, H Robins, H Tannenhauser, J TI String theory on AdS(3) SO JOURNAL OF HIGH ENERGY PHYSICS LA English DT Article DE p-branes; black holes in string theory AB It was shown by Brown and Henneaux that the classical theory of gravity on AdS(3) has an infinite-dimensional symmetry group forming a Virasoro algebra. More recently, Giveon, Kutasov and Seiberg (GKS) constructed the corresponding Virasoro generators in the first-quantized string theory on AdS(3). In this paper, we explore various aspects of string theory on AdS(3) and study the relation between these two works. We show how semi-classical properties of the string theory reproduce many features of the AdS/CFT duality. Furthermore, we examine how the Virasoro symmetry of Brown and Henneaux is realized in string theory, and show how it leads to the Virasoro Ward identities of the boundary CFT. The Virasoro generators of GKS emerge naturally in this analysis. Our work clarifies several aspects of the GKS construction: why the Brown-Henneaux Virasoro algebra can be realized on the first-quantized Hilbert space, to what extent the free-field approximation is valid, and why the Virasoro generators act on the string worldsheet localized near the boundary of AdS(3). On the other hand, we find that the way the central charge of the Virasoro algebra is generated is different from the mechanism proposed by GKS. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Theoret Phys Grp, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. RP Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. EM deboer@lbl.gov; hooguri@lbl.gov; robins@physics.berkeley.edu; jetannen@thsrv.lbl.gov RI Ooguri, Hirosi/A-4407-2011 NR 27 TC 107 Z9 107 U1 0 U2 0 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1029-8479 J9 J HIGH ENERGY PHYS JI J. High Energy Phys. PD DEC PY 1998 IS 12 AR 026 PG 20 WC Physics, Particles & Fields SC Physics GA 200CU UT WOS:000080522700026 ER PT J AU Mauro, T Bench, G Sidderas-Haddad, E Feingold, K Elias, P Cullander, C AF Mauro, T Bench, G Sidderas-Haddad, E Feingold, K Elias, P Cullander, C TI Acute barrier perturbation abolishes the ca(2+) and k(+) gradients in murine epidermis: Quantitative measurement using PIXE SO JOURNAL OF INVESTIGATIVE DERMATOLOGY LA English DT Article DE epidermal permeability barrier ID HUMAN-SKIN; CALCIUM; DIFFERENTIATION; KERATINOCYTE; ION; LOCALIZATION; DISRUPTION; POTASSIUM; PROFILES; PROTEIN AB Epidermal permeability barrier homeostasis requires the delivery of lipids and hydrolytic enzymes by lamellar body exocytosis from the uppermost granular cells, a process that is upregulated following barrier disruption. As lamellar body secretion is controlled by ionic concentrations, especially Ca2+ and K+, we used a quantitative technique, microbeam proton-induced X-ray emission, to measure Ca2+, K+, Cl-, and P concentrations before and after acute barrier perturbation by acetone applications, We found a steep gradient of Ca2+ in normal tissue, peaking in the outer stratum granulosum, which disappeared after barrier disruption, and partially reformed as the barrier recovered. A similar gradient, peaking somewhat lower in the epidermis (i.e., at the stratum granulosum-stratum corneum interface), was found for K+. Epidermal concentrations of K+ also decreased after barrier abrogation, although to a lesser extent than Ca2+. In contrast, P and Cl- demonstrated distribution gradients at baseline, which remained unchanged after barrier disruption. These studies quantitate the levels of Ca2+, K+, Cl-, and P within specific epidermal cell layers at baseline, and in relation to changes in permeability barrier integrity. Ca2+ and K+, but not Cl- or P, decrease after barrier disruption, consistent with these two ion's role in barrier repair. C1 Vet Affairs Med Ctr, Dermatol Serv 190, San Francisco, CA 94121 USA. Vet Affairs Med Ctr, Med Metab Serv, San Francisco, CA 94121 USA. Univ Calif Lawrence Livermore Natl Lab, Ctr Accelerator Mass Spectrometry, Livermore, CA USA. Univ Calif San Francisco, Dept Dermatol, San Francisco, CA 94143 USA. Univ Calif San Francisco, Dept Med, San Francisco, CA 94143 USA. Univ Calif San Francisco, Ctr Accelerator Mass Spectrometry Biopharmaceut S, San Francisco, CA 94143 USA. RP Mauro, T (reprint author), Vet Affairs Med Ctr, Dermatol Serv 190, 4150 Clement St, San Francisco, CA 94121 USA. FU NIAMS NIH HHS [AR44341, AR46019, AR19098] NR 27 TC 109 Z9 112 U1 0 U2 4 PU BLACKWELL SCIENCE INC PI MALDEN PA 350 MAIN ST, MALDEN, MA 02148 USA SN 0022-202X J9 J INVEST DERMATOL JI J. Invest. Dermatol. PD DEC PY 1998 VL 111 IS 6 BP 1198 EP 1201 DI 10.1046/j.1523-1747.1998.00421.x PG 4 WC Dermatology SC Dermatology GA 145PT UT WOS:000077381000045 PM 9856840 ER PT J AU Aloia, JF Vaswani, A Flaster, E Ma, R AF Aloia, JF Vaswani, A Flaster, E Ma, R TI Relationship of body water compartments to age, race, and fat-free mass SO JOURNAL OF LABORATORY AND CLINICAL MEDICINE LA English DT Article ID DUAL-PHOTON-ABSORPTIOMETRY; X-RAY ABSORPTIOMETRY; NEUTRON-ACTIVATION; EXCHANGEABLE HYDROGEN; DENSITY; NITROGEN; POTASSIUM; DILUTION; MODELS; WOMEN AB Water compartments were studied in 72 black and 128 white women, aged 20 to 70 years. Total body water (TBW) was measured by tritiated water dilution, and extracellular water (ECW) was measured by using delayed gamma neutron activation for the determination of total body chloride. Intracellular water (ICW) was assessed as the difference between TBW and ECW. Fat-free mass (FFM) was estimated by the measurement of total body potassium (TBK) and total body fat (TBF) by measurement of total body carbon (IBC). Total body protein was calculated from total body nitrogen (TBN). TBW was found to decline with age and to also be significantly influenced by body size. The extracellular water space was 41.5% of TBW. The decline of TBW with age is due primarily to a decline in ICW. The hydration of the FFM increased with age for the overall population because of a decline in TBK and TBN and an increase in ECW. Body composition models that have assumed constancy of hydration should be adjusted not only for gender but for age and body size. C1 Winthrop Univ Hosp, Dept Med, Mineola, NY 11501 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. RP Aloia, JF (reprint author), Winthrop Univ Hosp, Dept Med, 259 1st St, Mineola, NY 11501 USA. FU NIAMS NIH HHS [R01-AR37520-05]; NIDDK NIH HHS [P01-DK42618] NR 39 TC 18 Z9 19 U1 0 U2 1 PU MOSBY-ELSEVIER PI NEW YORK PA 360 PARK AVENUE SOUTH, NEW YORK, NY 10010-1710 USA SN 0022-2143 J9 J LAB CLIN MED JI J. Lab. Clin. Med. PD DEC PY 1998 VL 132 IS 6 BP 483 EP 490 DI 10.1016/S0022-2143(98)90126-3 PG 8 WC Medical Laboratory Technology; Medicine, General & Internal; Medicine, Research & Experimental SC Medical Laboratory Technology; General & Internal Medicine; Research & Experimental Medicine GA 145XQ UT WOS:000077398000010 PM 9851738 ER PT J AU Chang, JJ Warner, BE Dragon, EP Martinez, MW AF Chang, JJ Warner, BE Dragon, EP Martinez, MW TI Precision micromachining with pulsed green lasers SO JOURNAL OF LASER APPLICATIONS LA English DT Review DE laser materials processing; laser micromachining; microfabrication; copper vapor lasers ID ABLATION AB We have developed high-precision machining based on high-power pulsed green lasers (30-40 ns pulse width) at multi-kHz repetition rate. Dynamics of material removal has been investigated using a copper vapor laser. We found that noticeable surface evaporation starts to appear as laser intensity exceeds 10(7) W/cm(2). Material removal is then dominated by ablation at higher laser intensities. However, strong plasma absorption starts to appear as laser intensity exceeds 2GW/cm(2). This prolongs material heating by hot plasma via electron conduction, resulting in noticeable melt formation and expulsion. Maintaining laser radiance below the plasma-ignition threshold minimizes this melt formation. The optimum rate of ablation on metals was found to be similar to 1 mu m/pulse with a laser fluence of 50 J/cm(2). Higher material removal rate can be achieved at higher fluence, but is mostly accompanied with unwanted melt formation and ejection. By keeping laser intensity within a few GW/cm(2), we have demonstrated high-aspect-ratio machining with micron-scale accuracy and negligible heat affected zone. High-quality percussion drilling, trepanning, grooving, and slotting were demonstrated on metals and ceramics with a negligible heat affected zone. Straight holes with sizes varying from 500 to less than 25 mu m were consistently drilled with a height-to-diameter ratio up to 40. The high quality machining with scalable machining speed promises expanded use of pulsed green lasers in micromachining. (C) 1998 Laser Institute of America. [S1042-346X(98)00906-1]. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Chang, JJ (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808,L-463, Livermore, CA 94550 USA. NR 12 TC 76 Z9 76 U1 2 U2 6 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1042-346X J9 J LASER APPL JI J. Laser Appl. PD DEC PY 1998 VL 10 IS 6 BP 285 EP 291 PG 7 WC Materials Science, Multidisciplinary; Optics; Physics, Applied SC Materials Science; Optics; Physics GA 143WQ UT WOS:000077280800007 ER PT J AU Barker, BI Polukhina, L Poco, JF Hrubesh, LW Osheroff, DD AF Barker, BI Polukhina, L Poco, JF Hrubesh, LW Osheroff, DD TI Spin dynamics of He-3 in aerogel SO JOURNAL OF LOW TEMPERATURE PHYSICS LA English DT Article; Proceedings Paper CT International Symposium on Quantum Fluids and Solids (QFS98) CY JUN 09-14, 1998 CL AMHERST, MASSACHUSETTS ID SUPERFLUID STATE AB We report continuous-wave NMR measurements on superfluid(3) He contained inside high porosity aerogel at 3.24 MPa, in a 28.4 mT magnetic field, and down to 0.9 mK. Three different purities of He-3 were used: pure He-3, He-3 with enough He-4 to replace the first localized layer, and He-3 with enough He-4 to replace both localized layers. Below 2.26mK, the NMR spectrum does not consist of a single Lorentzian, but a distribution of NMR resonant frequencies both above and below the Larmor frequency, wt. Upon cooling, the component of the spectrum at frequencies below the Larmor frequency moves to higher frequencies over a narrow temperature range and does not return to w < w(L) upon warming. The higher frequency component of the spectrum displays two resolvable peaks which become a complex structure upon removal of the localized He-3 spins. The spectrum changes as the magnetic field is rotated about the axis of the aerogel sample, indicating that the 3He is able to detect a preferred direction in the aerogel. The shape of the spectrum shows no rotation or magnetic field hysteresis. We find that the average frequency shifts of our NMR spectra do not depend on the presence of the localized 3He spins. These frequency shifts and the presence of a temperature-independent magnetization for the liquid 3He suggest that the aerogel stabilizes a single equal-spin-pairing state in our experiments. C1 Stanford Univ, Dept Phys, Stanford, CA 94305 USA. Lawrence Livermore Natl Labs, Livermore, CA 94550 USA. RP Barker, BI (reprint author), Stanford Univ, Dept Phys, Stanford, CA 94305 USA. NR 8 TC 20 Z9 20 U1 1 U2 2 PU PLENUM PUBL CORP PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0022-2291 J9 J LOW TEMP PHYS JI J. Low Temp. Phys. PD DEC PY 1998 VL 113 IS 5-6 BP 635 EP 644 DI 10.1023/A:1022534124285 PG 10 WC Physics, Applied; Physics, Condensed Matter SC Physics GA 140RA UT WOS:000077101100001 ER PT J AU Fernandez, A Gibbons, MR Wall, MA Cerjan, CJ AF Fernandez, A Gibbons, MR Wall, MA Cerjan, CJ TI Magnetic domain structure and magnetization reversal in submicron-scale Co dots SO JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS LA English DT Article; Proceedings Paper CT Workshop Marking the 10th Anniversary of the Magnetic Force Microscope (MFM10) CY JAN 09-10, 1998 CL SAN FRANCISCO, CALIFORNIA DE magnetic force microscopy; Co dots; remanent states; magnetization reversal; micromagnetic simulations ID INTERFERENCE LITHOGRAPHY; FORCE MICROSCOPY; SWITCHING FIELD; COBALT ISLANDS; PARTICLES; NUCLEATION; ARRAYS; NICKEL AB We present a magnetic force microscopy (MFM) analysis of arrays of submicron-scale Co dots fabricated by interference lithography. The dots are thin (180-300 Angstrom) and elliptical in shape. MFM reveals that these structures relax into highly ordered remanent states whose symmetry and configuration are governed by their shape anisotropy. In particular, when the dots are saturated along their long-axis, a uniformly magnetized state persists at remanence. However, when the dots are saturated along their short-axis, they relax into a single-vortex state in which the circulation can have either sign. Both states are characterized by smoothly varying magnetization patterns and a high degree of uniformity across the array. We attribute the ordered behavior of these structures to the film microstructure, which allows the shape anisotropy to dominate over magnetocrystalline anisotropy. By imaging a series of minor-loop remanent states, we show that magnetization reversal in these structures occurs via the nucleation and annihilation of a single vortex. Magnetic hysteresis loop measurements are consistent with these observations and provide additional details. Furthermore, we present the results of micromagnetic simulations, which are in excellent agreement with both the MFM images and the hysteresis loop measurements. (C) 1998 Published by Elsevier Science B.V. All rights reserved. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Fernandez, A (reprint author), Etec Syst Inc, 24640 Corp Ave, Hayward, CA 94545 USA. NR 21 TC 74 Z9 74 U1 1 U2 14 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-8853 J9 J MAGN MAGN MATER JI J. Magn. Magn. Mater. PD DEC PY 1998 VL 190 IS 1-2 BP 71 EP 80 DI 10.1016/S0304-8853(98)00267-4 PG 10 WC Materials Science, Multidisciplinary; Physics, Condensed Matter SC Materials Science; Physics GA 143EL UT WOS:000077242000008 ER PT J AU Hawley, ME Brown, GW Markiewicz, DJ Spaepen, F Barth, EP AF Hawley, ME Brown, GW Markiewicz, DJ Spaepen, F Barth, EP TI Magnetic force microscopy observation of the magnetic structure of deformation induced shear bands in amorphous Fe80B16Si4 SO JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS LA English DT Article; Proceedings Paper CT Workshop Marking the 10th Anniversary of the Magnetic Force Microscope (MFM10) CY JAN 09-10, 1998 CL SAN FRANCISCO, CALIFORNIA DE MFM; amorphous ribbons; residual stress; deformation ID METAL RIBBONS; DOMAINS AB Processing-induced magnetic structures in amorphous metallic alloys are of interest because of their impact on performance of materials use in electrical device applications. In these situations, plastic deformation associated with cutting or bending the material to the desired shape occurs through the formation of shear bands. The stress associated with these shear bands induces magnetic domains that can lead to power losses through interaction with the fields and currents involved in normal device operation. These domains have been studied previously using a variety of techniques capable of imaging magnetic domain structures. In an effort to better characterize and understand these issues, we have applied magnetic force microscopy to these materials to provide submicrometer scale magnetic resolution and three-dimensional micrometer scale topographic resolution. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. Univ Calif Los Alamos Natl Lab, Ctr Mat Sci, Los Alamos, NM 87545 USA. Princeton Univ, Dept Chem, Princeton, NJ 08544 USA. Harvard Univ, Div Engn & Appl Sci, Cambridge, MA 02138 USA. RP Hawley, ME (reprint author), Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, MST-8, Los Alamos, NM 87545 USA. RI Milliron, Delia/D-6002-2012 NR 15 TC 5 Z9 5 U1 1 U2 7 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-8853 J9 J MAGN MAGN MATER JI J. Magn. Magn. Mater. PD DEC PY 1998 VL 190 IS 1-2 BP 89 EP 97 DI 10.1016/S0304-8853(98)00283-2 PG 9 WC Materials Science, Multidisciplinary; Physics, Condensed Matter SC Materials Science; Physics GA 143EL UT WOS:000077242000010 ER PT J AU Lambrakos, SG Milewski, JO AF Lambrakos, SG Milewski, JO TI A general approach based on constrained parameter-optimization for the implicit representation of information concerning welding processes SO JOURNAL OF MATERIALS ENGINEERING AND PERFORMANCE LA English DT Article DE complex morphology; constraints; deep penetration; elliptic problem; generating function; parameter optimization ID GEOMETRIC CONSTRAINTS; PENETRATION AB An analysis of weld morphology which typically occurs in deep penetration welding processes using electron or laser beams is presented. The method of analysis is based on geometric constraints with formal mathematical foundation within the theory of constrained parameter optimization. The analysis presented in this report serves as an example of the application of the geometric-constraints method to the analysis of weld fusion boundary morphology where there can be fragmented and incomplete information concerning material properties and only approximate information concerning the character of energy deposition, thus making a direct first principals approach difficult. A significant aspect of the geometric-constraints method is that it permits the implicit representation of information concerning temperature dependence of material properties and of coupling between heat transfer and fluid convection occurring in the weld meltpool. C1 USN, Div Mat Sci & Technol, Res Lab, Washington, DC 20375 USA. Univ Calif Los Alamos Natl Lab, Met Grp, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. RP Lambrakos, SG (reprint author), USN, Div Mat Sci & Technol, Res Lab, Code 6324, Washington, DC 20375 USA. NR 10 TC 0 Z9 0 U1 1 U2 1 PU ASM INTERNATIONAL PI MATERIALS PARK PA SUBSCRIPTIONS SPECIALIST CUSTOMER SERVICE, MATERIALS PARK, OH 44073-0002 USA SN 1059-9495 J9 J MATER ENG PERFORM JI J. Mater. Eng. Perform. PD DEC PY 1998 VL 7 IS 6 BP 761 EP 771 DI 10.1361/105994998770347332 PG 11 WC Materials Science, Multidisciplinary SC Materials Science GA 151PV UT WOS:000077730400009 ER PT J AU Siegal, MP Overmyer, DL Venturini, EL Dominguez, F Padilla, RR AF Siegal, MP Overmyer, DL Venturini, EL Dominguez, F Padilla, RR TI A new hybrid two-zone/crucible furnace process for the growth of epitaxial Tl2Ba2CaCu2O8 superconducting films SO JOURNAL OF MATERIALS RESEARCH LA English DT Article ID TLBA2CACU2O7 THIN-FILMS; CU-O SUPERCONDUCTORS; ZERO RESISTANCE AB Epitaxial Tl2Ba2CaCu2O8 (Tl-2212) films similar to 5500 Angstrom thick are grown on LaAlO3(100) substrates using a new hybrid two-zone/crucible furnace process enabling precise control of thallination. This method combines the best features of both conventional crucible and two-zone processing for the first time: superb film properties and reduced handling of hazardous Tl-oxide powders. Single-phase, highly c-axis oriented Tl-2212 films are grown with smooth morphology, Meissner transition similar to 103 K, and critical current density similar to 1.1 x 10(7) A/cm(2) at 5 K for twenty consecutive runs without having to change or add to the Tl-oxide source. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Siegal, MP (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 9 TC 5 Z9 5 U1 0 U2 0 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DR, WARRENDALE, PA 15086 USA SN 0884-2914 J9 J MATER RES JI J. Mater. Res. PD DEC PY 1998 VL 13 IS 12 BP 3349 EP 3352 DI 10.1557/JMR.1998.0453 PG 4 WC Materials Science, Multidisciplinary SC Materials Science GA 143WG UT WOS:000077280000001 ER PT J AU Huang, Y Vuchic, BV Carmody, M Baldo, PM Merkle, KL Buchholz, DB Mahajan, S Lei, JS Markworth, PR Chang, RPH Marks, LD AF Huang, Y Vuchic, BV Carmody, M Baldo, PM Merkle, KL Buchholz, DB Mahajan, S Lei, JS Markworth, PR Chang, RPH Marks, LD TI The mechanism of sputter-induced epitaxy modification in YBCO (001) films grown on MgO (001) substrates SO JOURNAL OF MATERIALS RESEARCH LA English DT Article ID YBA2CU3O7-X THIN-FILMS; ORGANOMETALLIC-BEAM-EPITAXY; GRAIN-BOUNDARY JUNCTIONS; SINGLE-CRYSTAL MGO; TRANSPORT-PROPERTIES; INPLANE ORIENTATION; 100 MGO; MICROSTRUCTURE; NUCLEATION; MGO(001) AB The sputter-induced epitaxy change of in-plane orientation occurring in YBa2Cu3O7-x (001) thin films grown on MgO (001) substrates by pulsed organo-metallic beam epitaxy (POMBE) is investigated by a series of film growth and characterization experiments, including RES and TEM. The factors influencing the orientation change are systematically studied. The experimental results suggest that the substrate surface morphology change caused by the ion sputtering and the Ar ion implantation in the substrate surface layer are not the major factors that affect the orientation change. Instead, the implantation of W ions, which come from the hot filament of the ion gun, and the initial Ba deposition layer in the YBCO film growth play the most important roles in controlling the epitaxy orientation change. Microstructure studies show that a BaxMg1-xO buffer layer is formed on top of the sputtered substrate surface due to Ba diffusion into the W implanted layer. It is believed that the formation of this buffer layer relieves the large lattice mismatch and changes the YBCO film from the 45 degrees oriented growth to the 0 degrees oriented growth. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Northwestern Univ, Dept Mat Sci & Engn, Evanston, IL 60201 USA. RP Huang, Y (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Marks, Laurence/B-7527-2009; Chang, R.P.H/B-7505-2009 NR 40 TC 0 Z9 0 U1 0 U2 1 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DR, WARRENDALE, PA 15086 USA SN 0884-2914 J9 J MATER RES JI J. Mater. Res. PD DEC PY 1998 VL 13 IS 12 BP 3378 EP 3388 DI 10.1557/JMR.1998.0460 PG 11 WC Materials Science, Multidisciplinary SC Materials Science GA 143WG UT WOS:000077280000008 ER PT J AU Swaminarayan, S LeSar, R Lomdahl, P Beazley, D AF Swaminarayan, S LeSar, R Lomdahl, P Beazley, D TI Short-range dislocation interactions using molecular dynamics: Annihilation of screw dislocations SO JOURNAL OF MATERIALS RESEARCH LA English DT Article ID CORE STRUCTURE AB We present results of a large-scale atomistic study of the annihilation of oppositely signed screw dislocations in an fee metal using molecular dynamics (MD) and an Embedded-Atom-Method (EAM) potential for Cu, The mechanisms of the annihilation process are studied in detail. From the simulation results, we determined the interaction energy between the dislocations as a function of separation. These results are compared with predictions from linear elasticity to examine the onset of non-linear-elastic interactions. The applicability of heuristic models for annihilation of dislocations in large-scale dislocation dynamics simulations is discussed in the light of these results. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Swaminarayan, S (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. RI LeSar, Richard/G-1609-2012 NR 21 TC 9 Z9 9 U1 0 U2 2 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DR, WARRENDALE, PA 15086 USA SN 0884-2914 J9 J MATER RES JI J. Mater. Res. PD DEC PY 1998 VL 13 IS 12 BP 3478 EP 3484 DI 10.1557/JMR.1998.0475 PG 7 WC Materials Science, Multidisciplinary SC Materials Science GA 143WG UT WOS:000077280000023 ER PT J AU Simner, SP Xiao, P Derby, B AF Simner, SP Xiao, P Derby, B TI Processing and microstructural characterisation of RBSiC-TaSi2 composites SO JOURNAL OF MATERIALS SCIENCE LA English DT Article ID SILICON-CARBIDE; MELT INFILTRATION AB Reaction bonded silicon carbide (RBSiC) ceramics typically contain 10 vol% silicon inherent to the reaction bonding process. However, the relatively low melting point (1410 degrees C) of the silicon phase is a limiting factor in the high temperature use of RBSiC materials. The application temperature can potentially be enhanced by replacing the silicon with more refractory metal disilicide phases. In this paper we report the infiltration of SiC-graphite compacts with alloyed Si-Ta melts in an attempt to precipitate TaSi2 (T-m = 2040 degrees C) in place of the residual silicon. High density RBSiC-TaSi2 ceramics with virtually no porosity were readily produced, but subsequent XRD and SEM examination revealed that the silicon phase was not completely removed. In addition, the materials possessed complex, inhomogeneous microstructures and were susceptible to various types of crack formation phenomena. (C) 1998 Kluwer Academic Publishers. C1 Univ Oxford, Dept Mat Sci & Engn, Oxford OX1 3PH, England. RP Simner, SP (reprint author), Pacific NW Natl Lab, Dept Mat Sci, Richland, WA 99352 USA. RI Derby, Brian/E-3529-2010 OI Derby, Brian/0000-0001-5753-0166 NR 21 TC 6 Z9 7 U1 1 U2 4 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0022-2461 J9 J MATER SCI JI J. Mater. Sci. PD DEC 1 PY 1998 VL 33 IS 23 BP 5557 EP 5568 DI 10.1023/A:1004447727931 PG 12 WC Materials Science, Multidisciplinary SC Materials Science GA 170YF UT WOS:000078834200006 ER PT J AU Plucknett, KP Lewis, MH AF Plucknett, KP Lewis, MH TI Microstructure and fracture toughness of Si3N4 based ceramics subjected to pre-sinter heat treatments SO JOURNAL OF MATERIALS SCIENCE LETTERS LA English DT Article C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. Univ Warwick, Ctr Adv Mat Technol, Coventry CV4 7AL, W Midlands, England. RP Plucknett, KP (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, POB 2008, Oak Ridge, TN 37831 USA. NR 13 TC 8 Z9 8 U1 0 U2 0 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0261-8028 J9 J MATER SCI LETT JI J. Mater. Sci. Lett. PD DEC 1 PY 1998 VL 17 IS 23 BP 1987 EP 1990 DI 10.1023/A:1006656505995 PG 4 WC Materials Science, Multidisciplinary SC Materials Science GA 170ZY UT WOS:000078838400010 ER PT J AU Suenram, RD Lovas, FJ Walker, ARH Dixon, DA AF Suenram, RD Lovas, FJ Walker, ARH Dixon, DA TI Rotational spectrum, structure, and electric dipole moment of bis(difluoromethyl) ether SO JOURNAL OF MOLECULAR SPECTROSCOPY LA English DT Article ID THERMODYNAMIC PROPERTIES AB The rotational spectrum of bis(difluoromethyl) ether (CF(2)HOCF(2)H) has been observed and analyzed using both a conventional Stark-modulated microwave spectrometer and a pulsed molecular beam Fabry-Perot cavity microwave (FTMW) spectrometer. The lowest energy conformer studied here has a (hydrogen) syn-anti conformation. The high sensitivity of the FTMW spectrometer permits observation and analysis of the (13)C, (18)O and (2)H isotopomers in natural abundance. The electric dipole moment was measured for the normal species and found to be mu(a), = 5.020(7) x 10(-30) C.m [1.505(2) D], mu(b) = 0.19(4) x 10(-30) C.m [0.056(11) D], mu(c) = 0.48(2) x 10(-30) C.m [0.144(7) D], and mu(T) = 5.047(10) x 10(-30) C.m [1.513(3) D]. C1 Natl Inst Stand & Technol, Opt Technol Div, Gaithersburg, MD 20899 USA. Pacific NW Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Suenram, RD (reprint author), Natl Inst Stand & Technol, Opt Technol Div, Gaithersburg, MD 20899 USA. RI Hight Walker, Angela/C-3373-2009 OI Hight Walker, Angela/0000-0003-1385-0672 NR 16 TC 3 Z9 3 U1 0 U2 0 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0022-2852 J9 J MOL SPECTROSC JI J. Mol. Spectrosc. PD DEC PY 1998 VL 192 IS 2 BP 441 EP 448 DI 10.1006/jmsp.1998.7713 PG 8 WC Physics, Atomic, Molecular & Chemical; Spectroscopy SC Physics; Spectroscopy GA 145FH UT WOS:000077360000022 ER PT J AU Corrales, LR AF Corrales, LR TI Immiscibility in binary silicates: chemical and phase equilibria SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article ID STATISTICAL MECHANICAL MODEL; ALKALI SILICATES; THERMODYNAMICS; SYSTEMS AB The driving force for immiscibility in binary silicates was examined using a statistical theory which combines a Flory-type theory, based on the compatibility of structural units, and a chemical equilibrium model, that describes the preferred associated species distribution of silicates. Restrictions imposed by a preferred distribution of associated species lead to a limitation of the number of ways to form a complete network structure, or equivalently to a decrease in the configurational entropy. An increase in configurational entropy is achieved by inducing a phase separation. The role of the enthalpies of species formation is examined relative to the configurational entropic contribution to phase coexistence. The theory leads to a rich set of phase coexistence behavior that includes three-phase equilibrium and a higher order critical point. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Pacific NW Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Corrales, LR (reprint author), Pacific NW Lab, Environm Mol Sci Lab, POB 999 K1-96, Richland, WA 99352 USA. NR 23 TC 1 Z9 1 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3093 J9 J NON-CRYST SOLIDS JI J. Non-Cryst. Solids PD DEC 1 PY 1998 VL 242 IS 1 BP 1 EP 13 DI 10.1016/S0022-3093(98)00782-0 PG 13 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA 149EK UT WOS:000077592000001 ER PT J AU Widmayer, CC Jones, LR Milam, D AF Widmayer, CC Jones, LR Milam, D TI Measurement of the nonlinear coefficient of carbon disulfide using holographic self-focusing SO JOURNAL OF NONLINEAR OPTICAL PHYSICS & MATERIALS LA English DT Article ID OBSCURATIONS; IMAGES; LASER AB We report a measurement of the nonlinear refractive index coefficient, gamma, of Carbon Disulfide (CS2), taken at a wavelength of 1.053 mu m. The measurement uses a new technique based on the generation of high fluence holographic images of obscurations by self-focusing in the CS2. Near-field beam distortion measurements are used in conjunction with detailed wave propagation analysis. The approach is attractive because it utilizes a sensitive near-field fluence measurement, it is tolerant of intensity modulation in the measurement beam, and it is straightforward to model with the computer. A value of gamma = (3.1 +/- 0.3) x 10(-14) cm(2)/W is obtained. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Widmayer, CC (reprint author), Univ Calif Lawrence Livermore Natl Lab, 7000 East Ave,L-465, Livermore, CA 94550 USA. NR 14 TC 4 Z9 5 U1 4 U2 4 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA JOURNAL DEPT PO BOX 128 FARRER ROAD, SINGAPORE 912805, SINGAPORE SN 0218-1991 J9 J NONLINEAR OPT PHYS JI J. Nonlinear Opt. Phys. Mater. PD DEC PY 1998 VL 7 IS 4 BP 563 EP 570 DI 10.1142/S0218863598000417 PG 8 WC Optics; Physics, Applied SC Optics; Physics GA 158TQ UT WOS:000078133200009 ER PT J AU Jiang, W Weber, WJ Thevuthasan, S McCready, DE AF Jiang, W Weber, WJ Thevuthasan, S McCready, DE TI Accumulation and recovery of irradiation damage in He+ implanted alpha-SiC SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article ID BEAM-INDUCED AMORPHIZATION; INDUCED CRYSTALLINE; SILICON-CARBIDE; AMORPHOUS TRANSITION; SINGLE-CRYSTALS; RECRYSTALLIZATION AB In situ RES/Channeling (RBS/C) has been used to investigate damage accumulation and subsequent annealing behavior in single-crystal wafers of 6H-silicon carbide (alpha-SiC) irradiated at temperatures from 160 to 300 K with 390 keV He+ ions to fluences ranging from 7.5 x 10(18) to 1.0 x 10(20) He+/m(2). Damage recovery in the irradiated crystals was studied by isochronal annealing at temperatures up to 1170 K. The RBS/C results show that complete amorphization in alpha-SiC does not occur at 190 K for irradiation fluences up to 1.0 x 10(20) He(/)(+)m(2) (0.38 dpa at the damage peak). For a fluence of 4.5 x 10(19) He+/m(2), the relative amount of damage accumulated during irradiation at 190 K is a factor of 5 larger than that accumulated under irradiation at 300 K, which suggests a higher rate of simultaneous point defect recombination at 300 K. In post-irradiation isochronal annealing studies, the integrated damage profile for all irradiated samples decreased exponentially with increasing annealing temperature. At low relative ion fluences and comparable irradiation-induced defect concentrations, the defects produced by He+ irradiation at 160 K are more difficult to anneal at 300 K than those produced by Si+ irradiation at 160 K, which suggests that trapping of He atoms at defects may be inhibiting recombination. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Pacific NW Lab, Richland, WA 99352 USA. RP Jiang, W (reprint author), Pacific NW Lab, POB 999,MSIn K8-93,902 Battelle Blvd, Richland, WA 99352 USA. EM weilin.jiang@pnl.gov RI Weber, William/A-4177-2008; OI Weber, William/0000-0002-9017-7365; Jiang, Weilin/0000-0001-8302-8313 NR 20 TC 23 Z9 23 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD DEC PY 1998 VL 257 IS 3 BP 295 EP 302 DI 10.1016/S0022-3115(98)00452-8 PG 8 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 142GY UT WOS:000077193200007 ER PT J AU Honda, T Bartels, HW Uckan, NA Sugihara, M Okazaki, T Seki, Y AF Honda, T Bartels, HW Uckan, NA Sugihara, M Okazaki, T Seki, Y TI Transient behaviors of plasma and in-vessel components when considering divertor plasma state transition in a fusion reactor SO JOURNAL OF NUCLEAR SCIENCE AND TECHNOLOGY LA English DT Article DE ITER TOKAMAK; diverters; detached plasma; attached plasma; transient behavior; safety analysis; plasma dynamics; thermal analysis; impurities; disruption; density limit; beta limit; fusion reactors ID EVENTS; ITER AB Transient behaviors of plasma and in-vessel components have been investigated considering the divertor plasma state (detached/attached) transition. The SAFALY code consisting of a zero-dimensional plasma model and a one-dimensional heat transfer model of components has been modified to take account of the divertor plasma state transition on the basis of the updated divertor plasma physics. Several plasma events, i.e., over fueling, sudden auxiliary heating injection and confinement improvement events which would be expected to result in overpower, were selected for the International Thermonuclear Experimental Reactor (ITER) and the transient behaviors were calculated on the assumption of a combined failure of plasma control and machine interlock in addition with a postulated plasma transient. The results show that plasma burning passively terminates due to sublimated impurity penetration from the carbon target surface, but there are possibilities of dry out of the coolant for the high heat flux in sudden attached slate transition under the multifailure of plasma control. However, effects Ly the aggravating failure of the divertor are expected to be safely terminated by the confinement boundary, the vacuum vessel and its pressure suppression system. C1 Hitachi Ltd, Power & Ind Syst, R&D Div, Hitachi, Ibaraki 3191221, Japan. ITER Joint Cent Team, La Jolla, CA 92037 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. ITER Joint Cent Team, D-85448 Garching, Germany. Japan Atom Energy Res Inst, Naka Fus Res Estab, Naka, Ibaraki 3110102, Japan. RP Hitachi Ltd, Power & Ind Syst, R&D Div, Omika Cho,7 Chome, Hitachi, Ibaraki 3191221, Japan. EM honda@ehl.hitachi.co.jp NR 10 TC 2 Z9 2 U1 0 U2 0 PU TAYLOR & FRANCIS LTD PI ABINGDON PA 4 PARK SQUARE, MILTON PARK, ABINGDON OX14 4RN, OXON, ENGLAND SN 0022-3131 EI 1881-1248 J9 J NUCL SCI TECHNOL JI J. Nucl. Sci. Technol. PD DEC PY 1998 VL 35 IS 12 BP 916 EP 927 DI 10.1080/18811248.1998.9733964 PG 12 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 164HU UT WOS:000078458400009 ER PT J AU Rao, CV Wright, SJ Rawlings, JB AF Rao, CV Wright, SJ Rawlings, JB TI Application of interior-point methods to model predictive control SO JOURNAL OF OPTIMIZATION THEORY AND APPLICATIONS LA English DT Article DE model predictive control; interior-point methods; Riccati equation ID STABILITY; SYSTEMS; STATE AB We present a structured interior-point method for the efficient solution of the optimal control problem in model predictive control. The cost of this approach is linear in the horizon length, compared with cubic growth for a naive approach. We use a discrete-time Riccati recursion to solve the linear equations efficiently at each iteration of the interior-point method, and show that this recursion is numerically stable. We demonstrate the effectiveness of the approach by applying it to three process control problems. C1 Univ Wisconsin, Dept Chem Engn, Madison, WI 53706 USA. Argonne Natl Lab, Div Math & Comp Sci, Argonne, IL 60439 USA. RP Rao, CV (reprint author), Univ Wisconsin, Dept Chem Engn, 1415 Johnson Dr, Madison, WI 53706 USA. NR 29 TC 208 Z9 211 U1 0 U2 11 PU PLENUM PUBL CORP PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0022-3239 J9 J OPTIMIZ THEORY APP JI J. Optim. Theory Appl. PD DEC PY 1998 VL 99 IS 3 BP 723 EP 757 DI 10.1023/A:1021711402723 PG 35 WC Operations Research & Management Science; Mathematics, Applied SC Operations Research & Management Science; Mathematics GA 148FL UT WOS:000077494300007 ER PT J AU Datta-Gupta, A Yoon, S Barman, I Vasco, DW AF Datta-Gupta, A Yoon, S Barman, I Vasco, DW TI Streamline-based production-data integration into high-resolution reservoir models SO JOURNAL OF PETROLEUM TECHNOLOGY LA English DT Article C1 Texas A&M Univ, Dept Petr Engn, College Stn, TX 77843 USA. Berkeley Lab, Berkeley, CA USA. RP Datta-Gupta, A (reprint author), Texas A&M Univ, Dept Petr Engn, College Stn, TX 77843 USA. RI Vasco, Donald/I-3167-2016 OI Vasco, Donald/0000-0003-1210-8628 NR 6 TC 6 Z9 7 U1 0 U2 1 PU SOC PETROLEUM ENG PI RICHARDSON PA 222 PALISADES CREEK DR,, RICHARDSON, TX 75080 USA SN 0149-2136 J9 J PETROL TECHNOL JI J. Pet. Technol. PD DEC PY 1998 VL 50 IS 12 BP 72 EP 76 PG 5 WC Energy & Fuels; Engineering, Chemical; Engineering, Petroleum; Geosciences, Multidisciplinary SC Energy & Fuels; Engineering; Geology GA 145XK UT WOS:000077397500016 ER PT J AU Chaurasia, CS Chen, CE Rubin, J Dewey, SL AF Chaurasia, CS Chen, CE Rubin, J Dewey, SL TI Effects of tamoxifen on striatal dopamine and 5-hydroxytryptamine release in freely moving male rats: An in-vivo microdialysis investigation SO JOURNAL OF PHARMACY AND PHARMACOLOGY LA English DT Article ID FEMALE RATS; BREAST-CANCER; ACETYLCHOLINE-RELEASE; LOCOMOTOR-ACTIVITY; ESTROGEN; BRAIN; ESTRADIOL; ANTIESTROGENS; METABOLISM; HIPPOCAMPUS AB Recent studies indicating interaction of oestrogens with central cholinergic, dopaminergic and 5-HTergic systems have led to the assumption of a protective role of oestrogens in certain neurodegenerative disorders. The non-steroidal drug tamoxifen, a mixed oestrogen agonist-antagonist, has been shown to modulate central nervous system functions in the corpus striatum. In this study we used a microdialysis technique to examine the effects of tamoxifen upon the striatal dopaminergic and 5-HTergic systems in intact freely moving male rats. The extracellular levels of dopamine, 3,4-dihydroxyphenylacetic acid, homovanillic acid and 5-hydroxyindoleacetic acid were measured after intraperitoneal administration of either the control or tamoxifen, and were compared with their corresponding baseline levels. Significant 25-35% increases in the baseline levels of dopamine and 3,4-dihydroxyphenylacetic acid were observed after the highest doses of tamoxifen (1.5 mg kg(-1) and 3.0 mg kg(-1) respectively), whereas the lowest dose of tamoxifen (0.3 mg kg(-1)) elevated dopamine and 3,4-dihydroxyphenylacetic acid levels by a detectable 15% of the basal. In addition, the ratio of 3,4-dihydroxyphenylacetic acid-to-dopamine remained unchanged in comparison with that of the pretreatment levels. Whereas no change in the striatal 5-hydroxyindoleacetic acid concentrations was seen with the lowest and highest dose regimen, the intermediate dose elicited a moderate increase (20%) in basal 5-hydroxyindoleacetic acid levels. The pharmacological relevance of the effects of tamoxifen on the dopaminergic and 5-HTergic systems, as a prelude to the development of non-steroidal oestrogenic compounds in reducing the risk of neurodegenerative disorders such as Alzheimer's disease, is discussed. C1 St Johns Univ, Coll Pharm & Allied Hlth Profess, Jamaica, NY 11439 USA. Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. RP Chaurasia, CS (reprint author), US FDA, Div Bioequivalence, Room 123,Metropk N 2,7500 Standish Pl, Rockville, MD 20855 USA. NR 47 TC 10 Z9 10 U1 0 U2 0 PU ROYAL PHARMACEUTICAL SOC GREAT BRITAIN PI LONDON PA 1 LAMBETH HIGH ST, LONDON SE1 7JN, ENGLAND SN 0022-3573 J9 J PHARM PHARMACOL JI J. Pharm. Pharmacol. PD DEC PY 1998 VL 50 IS 12 BP 1377 EP 1385 PG 9 WC Pharmacology & Pharmacy SC Pharmacology & Pharmacy GA 168KG UT WOS:000078690600009 PM 10052853 ER PT J AU Wang, Y Stocks, GM Nicholson, DMC Shelton, WA AF Wang, Y Stocks, GM Nicholson, DMC Shelton, WA TI Noncollinear magnetism of Fe-rich FeNi alloys SO JOURNAL OF PHASE EQUILIBRIA LA English DT Article ID SPIN DYNAMICS; NI INVAR; ANTIFERROMAGNETISM; FERROMAGNETISM; IRON AB The magnetic structure of Fe-rich FeNi alloys has long been a subject of great scientific interest and controversy. In this study, the authors attempt to understand an interesting phenomenon that the average magnetic moment of the alloys in the gamma-phase (fcc) decreases dramatically in the composition range near 70% Fe. Although the observation was made more than 30 years ago, the nature of the mechanism for this moment collapse is still controversial. In this approach, the noncollinear locally self-consistent multiple-scattering (LSMS) method is applied to the magnetic structure calculation of large unit cell samples consisting of Fe and Ni atoms. The Fe and Ni atoms are randomly distributed on a fee lattice. The moment directions are initialized to be randomly oriented and then, as the self-consistent iterations proceed, are allowed to rotate to minimize the total energy. A stable magnetic structure of the alloy is determined by the final moment configuration. Results are compared with experiments and the possible existence of noncollinear magnetic structures are discussed. C1 Pittsburgh Supercomp Ctr, Pittsburgh, PA 15213 USA. Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. Oak Ridge Natl Lab, Computat Phys & Engn Div, Oak Ridge, TN 37831 USA. Oak Ridge Natl Lab, Div Math & Comp Sci, Oak Ridge, TN 37831 USA. RP Wang, Y (reprint author), Pittsburgh Supercomp Ctr, Pittsburgh, PA 15213 USA. RI Stocks, George Malcollm/Q-1251-2016 OI Stocks, George Malcollm/0000-0002-9013-260X NR 16 TC 0 Z9 0 U1 1 U2 6 PU ASM INTERNATIONAL PI MATERIALS PARK PA SUBSCRIPTIONS SPECIALIST CUSTOMER SERVICE, MATERIALS PARK, OH 44073-0002 USA SN 1054-9714 J9 J PHASE EQUILIB JI J. Phase Equilib. PD DEC PY 1998 VL 19 IS 6 BP 513 EP 516 DI 10.1361/105497198770341680 PG 4 WC Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering GA 149KM UT WOS:000077604400006 ER PT J AU Ice, GE Sparks, CJ Jiang, X Robertson, L AF Ice, GE Sparks, CJ Jiang, X Robertson, L TI Diffuse scattering measurements of static atomic displacements in crystalline binary solid solutions SO JOURNAL OF PHASE EQUILIBRIA LA English DT Article ID ABSORPTION FINE-STRUCTURE; X-RAY-SCATTERING; SOLUTION ALLOYS; ORDER AB Diffuse x-ray scattering from crystalline solid solutions is sensitive to both local chemical order and local bond distances. In short-range ordered alloys, fluctuations of chemistry and bond distances break the long-range symmetry of the crystal within a local region and contribute to the total energy of the alloy. Recent use of tunable synchrotron radiation to change the x-ray scattering contrast between elements has greatly advanced the measurement of bond distances between the three kinds of atom pairs found in crystalline binary alloys. The estimated standard deviation on these recovered static displacements approaches +/-0.001 Angstrom (+/-0.0001 nm), which is an order of magnitude more precise than obtained with extended x-ray absorption fine structure measurement. In addition, both the radial and tangential displacements can be recovered to five near neighbors and beyond, These static displacement measurements provide new information that challenges the most advanced theoretical models of binary crystalline alloys. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37830 USA. RP Ice, GE (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37830 USA. NR 30 TC 3 Z9 3 U1 0 U2 1 PU ASM INT PI MATERIALS PARK PA SUBSCRIPTIONS SPECIALIST CUSTOMER SERVICE, MATERIALS PARK, OH 44073-0002 USA SN 1054-9714 J9 J PHASE EQUILIB JI J. Phase Equilib. PD DEC PY 1998 VL 19 IS 6 BP 529 EP 537 DI 10.1361/105497198770341716 PG 9 WC Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering GA 149KM UT WOS:000077604400009 ER PT J AU Faulkner, JS Moghadam, NY Wang, Y Stocks, GM AF Faulkner, JS Moghadam, NY Wang, Y Stocks, GM TI Comparison of the electronic states of alloys from the coherent potential approximation and an order-N calculation SO JOURNAL OF PHASE EQUILIBRIA LA English DT Article ID RANDOM SUBSTITUTIONAL ALLOYS; TOTAL-ENERGY; SYSTEMS AB For historical reasons, the coherent potential approximation was originally proposed for isomorphous models of alloys in which all the atoms of a given species are assumed to have the same charge distribution. Order-N methods for density-functional theory local-density approximation calculations of the electronic structure for clusters of hundreds or thousands of atoms demonstrate that a polymorphous model, in which each atom is different, is more realistic. The predictive ability of isomorphous coherent potential approximations is studied by comparison with order-N calculations. C1 Florida Atlantic Univ, Alloy Res Ctr, Boca Raton, FL 33431 USA. Florida Atlantic Univ, Dept Phys, Boca Raton, FL 33431 USA. Pittsburgh Supercomp Ctr, Pittsburgh, PA 15213 USA. Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37830 USA. RP Faulkner, JS (reprint author), Florida Atlantic Univ, Alloy Res Ctr, Boca Raton, FL 33431 USA. EM faulkner@acc.fau.edu RI Stocks, George Malcollm/Q-1251-2016 OI Stocks, George Malcollm/0000-0002-9013-260X NR 36 TC 3 Z9 3 U1 0 U2 1 PU ASM INT PI MATERIALS PARK PA SUBSCRIPTIONS SPECIALIST CUSTOMER SERVICE, MATERIALS PARK, OH 44073-0002 USA SN 1054-9714 J9 J PHASE EQUILIB JI J. Phase Equilib. PD DEC PY 1998 VL 19 IS 6 BP 538 EP 542 DI 10.1361/105497198770341725 PG 5 WC Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering GA 149KM UT WOS:000077604400010 ER PT J AU Vergara, JJ Berges, JA Falkowski, PG AF Vergara, JJ Berges, JA Falkowski, PG TI Diel periodicity of nitrate reductase activity and protein levels in the marine diatom Thalassiosira weissflogii (Bacillariophyceae) SO JOURNAL OF PHYCOLOGY LA English DT Article DE diatoms; diel cycle; nitrate reductase; transcriptional regulation ID STEADY-STATE LIGHT; SKELETONEMA-COSTATUM; HIGHER-PLANTS; NITROGEN ASSIMILATION; GONYAULAX-POLYEDRA; GENE-EXPRESSION; PHOTOSYNTHESIS; LIMITATION; CARBON; PHYTOPLANKTON AB The diel variation and regulation of the enzyme nitrate reductase (NR) were examined in the diatom Thalassiosira weissflogii (Gru.) Fryxell et Hask. NR was purified, and polyclonal antibodies were raised to a 98-kD polypeptide. The antibodies cross-reacted only with proteins from closely related diatom species, suggesting significant epitopic variation of this enzyme within algal divisions. Neither NR enzymatic activity nor protein was detected in cells grown with ammonium as the sole nitrogen source; the addition of ammonium to cells growing on nitrate decreased both protein levels and enzyme activity by 40% within 2 h. In cells grown on a 12:12 h LD cycle, NR activity and NR protein levers were highly correlated with a peak at midday, a decrease toward the end of the photoperiod, and an increase in activity beginning near the end of the dark period. The addition of actinomycin D (an inhibitor of RNA synthesis) and cycloheximide (an inhibitor of protein synthesis) affected NR activity and NR protein levels identically, strongly suggesting that this nuclear-encoded protein is regulated primarily at a transcriptional level. The diel pattern of NR protein and activity ceased immediately following transfer to continuous light, indicating that the periodicity is not directly controlled by a circadian rhythm. Time-lagged cross-correlation analysis revealed a G-h phased difference between the minimum enzyme activity or protein levels and the maximum cellular carbon pool. On the basis of the experimental results, we develop a model proposing that (1) IVR activity is regulated primarily by transcriptional regulation of NR synthesis and that (2) the level of expression of the enzyme during a given day is correlated with the integrated pool of organic carbon accumulated during the preceding photoperiod. C1 Brookhaven Natl Lab, Div Oceanog & Atmospher Sci, Environm Biophys & Mol Biol Program, Upton, NY 11973 USA. RP Falkowski, PG (reprint author), Rutgers State Univ, Inst Marine & Coastal Sci, Environm Biophys & Mol Biol Program, 71 Dudley Rd, New Brunswick, NJ 08901 USA. RI Vergara, Juan/H-9808-2012; Berges, John /D-9520-2012 OI Vergara, Juan/0000-0003-4479-4693; Berges, John /0000-0002-3124-4783 NR 52 TC 49 Z9 50 U1 0 U2 18 PU PHYCOLOGICAL SOC AMER INC PI LAWRENCE PA 810 EAST 10TH ST, LAWRENCE, KS 66044 USA SN 0022-3646 J9 J PHYCOL JI J. Phycol. PD DEC PY 1998 VL 34 IS 6 BP 952 EP 961 DI 10.1046/j.1529-8817.1998.340952.x PG 10 WC Plant Sciences; Marine & Freshwater Biology SC Plant Sciences; Marine & Freshwater Biology GA 155VB UT WOS:000077966100007 ER PT J AU Robinson, L Johnson, E Zhao, L AF Robinson, L Johnson, E Zhao, L TI Study of the neutron flux in a model for a Cf-252 cold neutron source SO JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY LA English DT Article AB The flux of cold neutrons that is obtainable from various high energy neutron sources is studied for a particular model of a cold neutron source when the cold moderation region of the apparatus is at 20, 70, and 298K. The maximum flux obtained with a californium-252 source was 2.7.10(-3) cold neutron per (cm(2).second (source neutron)). This flux was obtained when the cold moderation region of the apparatus was at 20K and when the thermal moderator is either polyethylene or trimethylbenzene and the cold moderator is polyethylene. This flux should allow sensitive prompt and delayed neutron activation analysis measurements. C1 Florida A&M Univ, Inst Environm Sci, Tallahassee, FL 32307 USA. Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Robinson, L (reprint author), Florida A&M Univ, Inst Environm Sci, Tallahassee, FL 32307 USA. NR 12 TC 1 Z9 1 U1 0 U2 1 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0236-5731 J9 J RADIOANAL NUCL CH JI J. Radioanal. Nucl. Chem. PD DEC PY 1998 VL 238 IS 1-2 BP 25 EP 28 DI 10.1007/BF02385351 PG 4 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 155LL UT WOS:000077948400005 ER PT J AU Huang, BQ Corbett, JD AF Huang, BQ Corbett, JD TI Ba3AlO4H: Synthesis and structure of a new hydrogen-stabilized phase SO JOURNAL OF SOLID STATE CHEMISTRY LA English DT Article ID HYDRIDES; CLUSTERS AB The title compound and its deuteride were synthesized in high yield by sintering appropriate mixtures of BaH2(BaD2), BaO and Al2O3 in welded Ta containers at 1100 degrees C under a hydrogen (deuterium) pressure of 600-700 torr, The structure was determined by a combination of single crystal X-ray and time-of-flight powder neutron diffraction means (orthorhombic Pnma, Z = 4, a = 10.4911(9), b = 8.1518(7), c = 7.2399(6) Angstrom for the deuteride), The compound contains nominal Ba2+ cations, AlO45- complex anions and H-(D-) anions, The hydride is bound in a strongly distorted barium octahedron while the tetrahedral AlO45- anion is surrounded by eleven barium atoms in a peculiar polyhedral configuration. The HBa6 octahedra are linked together by corner-sharing to form a three dimension framework with large voids defined by eight of the HBa6 octahedra that are occupied by the tetrahedral AlO45- anions, The structure is closely related in a hierarchical way to that of orthorhombic inverse perovskitic Ba3GeO. (C) 1998 Academic Press. C1 Iowa State Univ Sci & Technol, US DOE, Ames Lab, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Dept Chem, Ames, IA 50011 USA. RP Corbett, JD (reprint author), Iowa State Univ Sci & Technol, US DOE, Ames Lab, Ames, IA 50011 USA. NR 28 TC 8 Z9 8 U1 0 U2 5 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0022-4596 J9 J SOLID STATE CHEM JI J. Solid State Chem. PD DEC PY 1998 VL 141 IS 2 BP 570 EP 575 DI 10.1006/jssc.1998.8022 PG 6 WC Chemistry, Inorganic & Nuclear; Chemistry, Physical SC Chemistry GA 153MP UT WOS:000077837100034 ER PT J AU Ma, B Hodges, JP Jorgensen, JD Miller, DJ Richardson, JW Balachandran, U AF Ma, B Hodges, JP Jorgensen, JD Miller, DJ Richardson, JW Balachandran, U TI Structure and property relationships in mixed-conducting Sr-4(Fe1-xCox)(6)O-13 +/-delta materials SO JOURNAL OF SOLID STATE CHEMISTRY LA English DT Article ID FUEL-CELLS; O SYSTEM; METHANE AB Mixed-conducting ceramic oxides have potential uses in high-temperature electrochemical applications such as solid-oxide fuel cells, batteries, sensors, and oxygen-permeable membranes. The Sr4(Fe1-xCox)6O13+/-delta system combines high electronic/ionic conductivity with appreciable oxygen permeability at elevated temperatures. Dense ceramic membranes made of this material can be used to separate high-purity oxygen from air without the need for external electrical circuitry or to partially oxidize methane to produce synthesis gas (syngas, CO + H2). Samples of Sr4(Fe1-xCox)6O13+/-delta (where x = , 0.1, 0.2, 0.333, and 0.467) were prepared by a solid-state reaction method in atmospheres with various oxygen partial pressure (pO2) and were characterized by powder X-ray diffraction, scanning electron microscopy, and electrical conductivity testing. The proportion of phase components in the samples is dependent on both cobalt content and pO2. The total conductivity increases with both temperature and cobalt substitution in the material. Current-voltage characteristics determined in a gas-tight cell indicate that a bulk effect, rather than a surface exchange effect, is the main limiting factor for oxygen permeation through membranes made of Sr4Fe4Co2 O13+/-delta (x = 0.333 sample). Oxygen permeability measurements at various temperatures showed that, as expected, permeability increases with increasing temperature. At 900 degrees C, an oxygen permeation flux of 2.5 scc.cm-2.min-1 was obtained from an Sr4Fe4Co2O13+/-delta disk membrane that was 2.9 mm thick. (C) 1998 Academic Press. C1 Argonne Natl Lab, Div Energy Technol, Argonne, IL 60439 USA. Argonne Natl Lab, Div Sci Mat, Argonne, IL 60439 USA. Argonne Natl Lab, Intense Pulsed Neutron Source, Argonne, IL 60439 USA. RP Balachandran, U (reprint author), Argonne Natl Lab, Div Energy Technol, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Hodges, Jason/K-1421-2013; Ma, Beihai/I-1674-2013; OI Ma, Beihai/0000-0003-3557-2773; Hodges, Jason/0000-0003-3016-4578 NR 22 TC 39 Z9 41 U1 0 U2 4 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0022-4596 J9 J SOLID STATE CHEM JI J. Solid State Chem. PD DEC PY 1998 VL 141 IS 2 BP 576 EP 586 DI 10.1006/jssc.1998.8023 PG 11 WC Chemistry, Inorganic & Nuclear; Chemistry, Physical SC Chemistry GA 153MP UT WOS:000077837100035 ER PT J AU Mitchell, JF Millburn, JE Medarde, M Short, S Jorgensen, JD Fernandez-Diaz, MT AF Mitchell, JF Millburn, JE Medarde, M Short, S Jorgensen, JD Fernandez-Diaz, MT TI Sr3Mn2O7 : Mn4+ parent compound of the n=2 layered CMR manganites SO JOURNAL OF SOLID STATE CHEMISTRY LA English DT Letter ID GIANT MAGNETORESISTANCE; OXYGEN STOICHIOMETRY; PEROVSKITE STRUCTURE; MAGNETIC-PROPERTIES; CRYSTAL-STRUCTURE; MANGANESE OXIDES; DIFFRACTION; TRANSITION AB We report the crystal and magnetic structures of the bilayer Ruddlesden-Popper phase Sr3Mn2O7-delta (delta=0.0, 0.45), The delta = 0.45 compound exhibits a large number of oxygen vacancies disordered in the MnO2 planes and is a nonmagnetic insulator. Sr3Mn2O7.0 (delta = 0) in an antiferromagnetic insulator whose magnetic structure is analogous to that of the related SrMnO3 perovskite, The stoichiometric layered material has a small distortion of its exclusively Mn4+O6 octahedra as a result of steric influence of the surrounding cations, Thus, it provides a baseline for structural distortions related to electronic and/or magnetic transitions in doped materials. (C) 1998 Academic Press. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Inst Max Von Laue Paul Langevin, Grenoble 9, France. RP Mitchell, JF (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Fernandez-Diaz, Maria Teresa/D-7373-2014 NR 26 TC 49 Z9 50 U1 2 U2 21 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0022-4596 J9 J SOLID STATE CHEM JI J. Solid State Chem. PD DEC PY 1998 VL 141 IS 2 BP 599 EP 603 DI 10.1006/jssc.1998.8026 PG 5 WC Chemistry, Inorganic & Nuclear; Chemistry, Physical SC Chemistry GA 153MP UT WOS:000077837100038 ER PT J AU Lanza, GM Trousil, RL Wallace, KD Rose, JH Hall, CS Scott, MJ Miller, JG Eisenberg, PR Gaffney, PJ Wickline, SA AF Lanza, GM Trousil, RL Wallace, KD Rose, JH Hall, CS Scott, MJ Miller, JG Eisenberg, PR Gaffney, PJ Wickline, SA TI In vitro characterization of a novel, tissue-targeted ultrasonic contrast system with acoustic microscopy SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article ID MONOCLONAL-ANTIBODIES; ELASTIC PROPERTIES; CARDIOMYOPATHY; ARCHITECTURE; QUANTIFICATION; BACKSCATTER; MECHANISMS; FIBRIN; AGENT AB Targeted ultrasonic contrast systems are designed to enhance the reflectivity of selected tissues in vivo [Lanza et nl., Circulation 94, 3334 (1996)]. In particular, these agents hold promise for the minimally invasive diagnosis and treatment of a wide array of pathologies, most notably tumors, thromboses, and inflamed tissues. In the present study, acoustic microscopy was used to assess the efficacy of a novel, perfluorocarbon based contrast agent to enhance the inherent acoustic reflectivity of biological and synthetic substrates. Data from these experiments were used to postulate a simple model describing the observed enhancements. Frequency averaged reflectivity (30-55 MHz) was shown to increase 7.0+/-1.1 dB for nitrocellulose membranes with targeted contrast. Enhancements of 36.0+/-2.3 dB and 8.5+/-0.9 dB for plasma and whole blood clots, respectively, were measured between 20 and 35 MHz. A proposed acoustic transmission Line model predicted the targeted contrast system would increase the acoustic reflectivity of the nitrocellulose membrane, whole blood clot, and fibrin plasma clot by 2.6, 8.0, and 31.8 dB, respectively. These predictions were in reasonable agreement with the experimental results of this paper. In conclusion, acoustic microscopy provides a rapid and sensitive approach for in vitro characterization, development, and testing of mathematical models of targeted contrast systems. Given the current demand for targeted contrast systems for medical diagnostic and therapeutic use, the use of acoustic microscopy may provide a useful tool in the development of these agents. (C) 1998 Acoustical Society of America. [S0001-4966(98)01412-X]. C1 Washington Univ, Barnes Jewish Hosp, Dept Med, Div Cardiol, St Louis, MO 63110 USA. Washington Univ, Dept Phys, St Louis, MO 63130 USA. Iowa State Univ Sci & Technol, Dept Phys & Astron, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. Natl Inst Biol Stand & Controls, Div Hematol, Potters Bar EN6 3QG, Herts, England. RP Rose, JH (reprint author), Washington Univ, Barnes Jewish Hosp, Dept Med, Div Cardiol, St Louis, MO 63110 USA. FU NHLBI NIH HHS [HL-59865] NR 39 TC 84 Z9 87 U1 0 U2 6 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0001-4966 J9 J ACOUST SOC AM JI J. Acoust. Soc. Am. PD DEC PY 1998 VL 104 IS 6 BP 3665 EP 3672 DI 10.1121/1.423948 PG 8 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA 145JM UT WOS:000077367500057 PM 9857523 ER PT J AU Ross, M Wenzel, T AF Ross, M Wenzel, T TI Untitled SO JOURNAL OF THE AIR & WASTE MANAGEMENT ASSOCIATION LA English DT Letter C1 Univ Michigan, Ann Arbor, MI 48109 USA. Lawrence Berkeley Lab, Berkeley, CA USA. RP Ross, M (reprint author), Univ Michigan, Ann Arbor, MI 48109 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU AIR & WASTE MANAGEMENT ASSOC PI PITTSBURGH PA ONE GATEWAY CENTER, THIRD FL, PITTSBURGH, PA 15222 USA SN 1047-3289 J9 J AIR WASTE MANAGE JI J. Air Waste Manage. Assoc. PD DEC PY 1998 VL 48 IS 12 BP 1134 EP 1134 PG 1 WC Engineering, Environmental; Environmental Sciences; Meteorology & Atmospheric Sciences SC Engineering; Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA 148GW UT WOS:000077497700001 ER PT J AU Besmann, TM AF Besmann, TM TI Thermochemical behavior of gallium in weapons-material-derived mixed-oxide light water reactor (LWR) fuel SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID FISSION-PRODUCTS AB The use of weapons-derived plutonium in light water reactor (LWR) fuel must consider the effects of up to 1 mass % of gallium that is used in weapons plutonium alloy. The potential effects of this residual gallium have been examined for 5% PuO2-95% UO2 from a thermochemical standpoint. The state and effect of gallium in the fuel are predicted, based on the oxygen potential of the fuel and the effects of burn-up. The possibility of vapor-phase transport of gallium to the fuel dad and potential interaction with the clad also is assessed. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Besmann, TM (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, POB 2008, Oak Ridge, TN 37831 USA. NR 10 TC 11 Z9 11 U1 1 U2 1 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43081-6136 USA SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD DEC PY 1998 VL 81 IS 12 BP 3071 EP 3076 DI 10.1111/j.1151-2916.1998.tb02740.x PG 6 WC Materials Science, Ceramics SC Materials Science GA 149CR UT WOS:000077588000002 ER PT J AU Moss, TS Lackey, WJ More, KL AF Moss, TS Lackey, WJ More, KL TI Chemical vapor deposition of B13C2 from BCl3-CH4-H-2-argon mixtures SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID BORON CARBIDES AB The deposition of boron carbide (B13C2) onto graphite substrates was accomplished by using a hot-wall chemical vapor deposition (CVD) reactor at a pressure of 10.1 kPa in the temperature range of 1000 degrees-1400 degrees C. A modified inpinging-jet geometry was used to simplify the mass-transfer analysis. Coatings were characterized using X-ray diffractometry (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The surface morphology was composed of well-defined facets, the size of which was dependent on the growth rate and deposition time, as would be expected from a competitive growth mechanism. TEM micrographs of the coating showed long, columnar grains that emanated from a narrow nucleation zone. The growth rate could be adequately described by a first-order kinetic expression, with respect to the bulk gas phase boron chloride (BCl3) concentration. The activation energy of the kinetic expression was estimated to be 93.1 kJ/mol, It was proposed that the deposition was limited by the adsorption of (BCl3) onto the substrate surface. C1 Georgia Inst Technol, Sch Mat Sci & Engn, Atlanta, GA 30332 USA. Georgia Inst Technol, George W Woodruff Sch Mech Engn, Atlanta, GA 30332 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Moss, TS (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. RI More, Karren/A-8097-2016 OI More, Karren/0000-0001-5223-9097 NR 27 TC 16 Z9 17 U1 1 U2 6 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43081-6136 USA SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD DEC PY 1998 VL 81 IS 12 BP 3077 EP 3086 DI 10.1111/j.1151-2916.1998.tb02741.x PG 10 WC Materials Science, Ceramics SC Materials Science GA 149CR UT WOS:000077588000003 ER PT J AU Ackler, HD AF Ackler, HD TI Healing of lithographically introduced cracks in glass and glass-containing ceramics SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID 96-PERCENT ALUMINA CERAMICS; CYLINDRICAL VOIDS; BOUNDARY GLASSES; MICROSTRUCTURE; SPHEROIDIZATION; CRYSTALLIZATION; INSTABILITY; SIMULATION; STABILITY; PARTICLES AB The morphological evolution of lithographically defined cracklike flaws in glass and glass-containing ceramics was studied at elevated temperatures. The systems studied have glass contents from 100 to approximately 0.5 vol%, providing insight to the contribution of viscous flow of the glass to crack healing over a range of glass contents spanning many industrial ceramics. Healing behavior is found to be controlled by viscous flow of glass in all cases except the lowest glass content, for which significant mass transport is only accomplished by diffusional mechanisms. This implies a change of mechanism below some critical glass content. C1 Univ Calif Berkeley, Dept Mat Sci & Mineral Engn, Berkeley, CA 94720 USA. RP Ackler, HD (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 57 TC 21 Z9 21 U1 2 U2 9 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43081-6136 USA SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD DEC PY 1998 VL 81 IS 12 BP 3093 EP 3103 DI 10.1111/j.1151-2916.1998.tb02743.x PG 11 WC Materials Science, Ceramics SC Materials Science GA 149CR UT WOS:000077588000005 ER PT J AU Gu, H Pan, XQ Cannon, RM Ruhle, M AF Gu, H Pan, XQ Cannon, RM Ruhle, M TI Dopant distribution in grain-boundary films in calcia-doped silicon nitride ceramics SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article; Proceedings Paper CT 97th Annual Meeting of the American-Ceramic-Society CY MAY 01-03, 1995 CL CINCINNATI, OHIO SP Amer Ceram Soc ID ENERGY-LOSS SPECTROSCOPY; INTERGRANULAR FILM; EQUILIBRIUM THICKNESS; GLASS; CHEMISTRY; FRACTURE; PHASES; GROWTH; SI3N4 AB Quantitative analyses of the local chemistry of amorphous films at the grain boundary (GB) were taken on hot isostatically pressed high-purity Si3N4 doped with various amounts of calcium (up to 450 ppm), This work was mainly accomplished by using spatially resolved electron energy-loss spectroscopy (EELS) in a dedicated scanning transmission electron microscope. The amount of calcium segregation, quantified in terms of GB excess, saturated in the films at a bulk-doping level of similar to 220 ppm. Extra additives did not stay at the triple-point glass pockets, where the calcium was almost expelled completely; instead, the additives stayed at intersections between the films and pockets. Otherwise, the calcium distribution was uniform along and across GB films, The latter was determined from simulations of EELS profiling. At grain/pocket interfaces, a much-lower segregation level occurred, ranging from one-half to one-tenth of the level at the GB. This observation indicates different segregation mechanisms in the two cases, Also, the calcium segregation in GB films changed the film composition dramatically, because more N3- ions were introduced and replaced O2- ions, to maintain the local stoichiometry. Reduction of the Van der Waals force has been proposed as being the origin of the film expansion with increasing calcium content. C1 Japan Sci & Technol Corp, Ceram Superplast Project, Nagoya, Aichi 456, Japan. Max Planck Inst Met Forsch, D-70174 Stuttgart, Germany. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Gu, H (reprint author), Japan Sci & Technol Corp, Ceram Superplast Project, Nagoya, Aichi 456, Japan. NR 33 TC 77 Z9 78 U1 0 U2 6 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43081-6136 USA SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD DEC PY 1998 VL 81 IS 12 BP 3125 EP 3135 DI 10.1111/j.1151-2916.1998.tb02747.x PG 11 WC Materials Science, Ceramics SC Materials Science GA 149CR UT WOS:000077588000009 ER PT J AU Ellison, AJG Hess, PC Naski, GC AF Ellison, AJG Hess, PC Naski, GC TI Cassiterite solubility in high-silica K2O-Al2O3-SiO2 liquids SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID SOLUTION MECHANISMS; GLASSES; MELTS; SPECIATION; BEHAVIOR; RAMAN; TIN AB The saturation surface of cassiterite, SnO2, was determined for Iiquids in the system K2O-Al2O3-SiO2 as a function of bulk composition and temperature. At fixed K2O/Al2O3 cassiterite solubility varies weakly with SiO2 concentration (76 to 84 mol%), temperature (1350 degrees to 1550 degrees C), and log (f(o2)) (-0.7 to -5.3). Cassiterite solubility is also approximately independent of composition in liquids with molar ratios of K2O/Al2O3 less than or equal to 1 (peraluminous liquids), As K2O/ Al2O3 increases from 1 (peralkaline liquids), however, cassiterite solubility increases steeply and approximately linearly with K2O in excess of Al2O3. It is proposed that potassium in excess of aluminum combines with Sn4+ to form quasi-molecular complexes with an effective stoichiometry of K4SnO4. C1 Argonne Natl Lab, Div Chem Technol, Argonne, IL 60439 USA. Brown Univ, Dept Geol Sci, Providence, RI 02912 USA. RP Ellison, AJG (reprint author), Corning Inc, Corning, NY 14831 USA. NR 22 TC 2 Z9 2 U1 2 U2 8 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43081-6136 USA SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD DEC PY 1998 VL 81 IS 12 BP 3215 EP 3220 DI 10.1111/j.1151-2916.1998.tb02758.x PG 6 WC Materials Science, Ceramics SC Materials Science GA 149CR UT WOS:000077588000020 ER PT J AU Swenson, D Nieh, TG Fournelle, JH AF Swenson, D Nieh, TG Fournelle, JH TI Solid-state phase relationships in the calcia-titania-zirconia system at 1200 degrees C SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID CAZRXTI3-XO7; ZIRCONOLITE AB Phase relationships were investigated in the CaO-TiO2-ZrO2 system at 1200 degrees C for compositions containing <50 mol% CaO using X-ray diffraction and electron probe microanalysis. The existence of two previously reported ternary phases, zirconolite (CaZrTi2O7) and calzirtite (Ca2Zr5Ti2O16), was confirmed, Each of these phases exhibited a significant range of homogeneity between TiO2 and ZrO2, while maintaining a nearly constant concentration of CaO. The ternary solubilities of the constituent binary phases were found to be small (typically <1 mol%), with the exceptions of the perovskites (CaTiO3 and CaZrO3). These latter phases displayed mutual solubilities of at least 22 mol% but exhibited significant variations in composition from grain to grain. Thermodynamic equilibrium was clearly not established in several samples, although most of the phase relationship information obtained was self-consistent. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Univ Wisconsin, Dept Geol & Geophys, Madison, WI 53706 USA. RP Swenson, D (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RI Nieh, Tai-Gang/G-5912-2011 OI Nieh, Tai-Gang/0000-0002-2814-3746 NR 14 TC 7 Z9 7 U1 0 U2 3 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43081-6136 USA SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD DEC PY 1998 VL 81 IS 12 BP 3249 EP 3252 DI 10.1111/j.1151-2916.1998.tb02763.x PG 4 WC Materials Science, Ceramics SC Materials Science GA 149CR UT WOS:000077588000025 ER PT J AU Quinn, NWT Karkoski, J AF Quinn, NWT Karkoski, J TI Real-time management of water quality in the San Joaquin River Basin, California SO JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION LA English DT Article DE water quality; real-time management; salts; drainage AB In the San Joaquin River Basin, California, a realtime water quality forecasting model was developed to help improve the management of saline agricultural and wetland drainage to meet water quality objectives. Predicted salt loads from the water quality forecasting model, SJRIODAY, were consistently within +/- 11 percent of actual, within +/- 14 percent for seven-day forecasts, and within +/- 26 percent for 14-day forecasts for the 16-month trial period. When the 48 days dominated by rainfall/runoff events were eliminated from the data set, the error bar decreased to +/- 9 percent for the model and +/- II percent and +/- 17 percent for the seven-day and 14-day forecasts, respectively. Constraints on the use of the model for salinity management on the San Joaquin River include the number of entities that control or influence water quality and the lack of a centralized authority to direct their activities. The lack of real-time monitoring sensors for other primary constituents of concern, such as selenium and boron, limits the application of the model to salinity at the present time. A case study describes wetland drainage releases scheduled to coincide with high river flows and significant river assimilative capacity for salt loads. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. US EPA, State Water Resources Control Board, Sacramento, CA 95814 USA. RP Quinn, NWT (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, 70A-3317K, Berkeley, CA 94720 USA. EM nquinn@mp405a.mp.usbr.gov OI Quinn, Nigel/0000-0003-3333-4763 NR 15 TC 7 Z9 7 U1 0 U2 1 PU AMER WATER RESOURCES ASSOC PI HERNDON PA 950 HERNDON PARKWAY SUITE 300, HERNDON, VA 20170-5531 USA SN 1093-474X J9 J AM WATER RESOUR AS JI J. Am. Water Resour. Assoc. PD DEC PY 1998 VL 34 IS 6 BP 1473 EP 1486 DI 10.1111/j.1752-1688.1998.tb05446.x PG 14 WC Engineering, Environmental; Geosciences, Multidisciplinary; Water Resources SC Engineering; Geology; Water Resources GA 158UE UT WOS:000078134800019 ER PT J AU Neudecker, BJ Zuhr, RA Kwak, BS Bates, JB Robertson, JD AF Neudecker, BJ Zuhr, RA Kwak, BS Bates, JB Robertson, JD TI Lithium manganese nickel oxides Li-x(MnyNi1-y)(2-x)O-2 - I. Synthesis and characterization of thin films and bulk phases SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID ELECTROCHEMISTRY; DEINTERCALATION; LIXNI2-XO2; NUCLEAR; CELLS; XPS; LI AB The series Li-x(MnyNi1-y)(2-x)O-2 for x less than or equal to 1.33 and 0.38 less than or equal to y less than or equal to 0.50 shows a very close relationship to its parent series LixNi2-xO2. The refined lattice parameters for at least 0.93 less than or equal to x less than or equal to 1.26 are a linear function of the concentration ratio Li/(Mn + Ni) which in turn is proportional to the averaged valence state of the transition metals, Li-x(MnyNi1-y)(2-x)O-x is able to reversibly coprecipitate/reinsert Li2O and release/absorb O-2. This self-regulation mechanism seems to always adjust the number of cations to an undisturbed oxygen sublattice according to the rule "cations/anions = 1," which holds true at least for temperatures up to 800 degrees C and oxygen partial pressures above 10(-5) atm. Samples prepared in air and under O-2 did not show nucleation of Li2O, not even for x > 1.0. The series Li-x(MnyNi1-y)(2-x)O-2 where 0.38 less than or equal to y less than or equal to 0.50 crystallizes in a rhombohedral unit cell (space group R (3) over bar m) for x < 1.15 and transforms into a single monoclinic phase (space group C2/c) for x > 1.25. The similarity between LixNi2-xO2 and Li-x(MnyNi1-y)(2-x)O-2 strongly suggests a rhombohedral --> cubic transition at x approximate to 0.6 for the latter series. Derived from the linear dependence of the X-ray density on the stoichiometric parameter x, an equation was found with which the lithium concentration of Li-x(MnyNi1-y)(2-x)O-2 thin film phases over the entire range 0 less than or equal to x less than or equal to 1.33 can be determined accurately without extensive ion-beam analysis. XPS measurements on a film with the bulk stoichiometry Li1.10Mn0.39Ni0.51O2 gave evidence for Mn4+ and Mn3+, but no indication was found for nickel valence states other than Ni2+. In order to meet, the above-given stoichiometry, the averaged nickel valence state had to increase with film depth. C1 Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Univ Kentucky, Dept Chem, Lexington, KY 40502 USA. RP Neudecker, BJ (reprint author), Oak Ridge Natl Lab, Div Solid State, POB 2008, Oak Ridge, TN 37831 USA. NR 34 TC 65 Z9 65 U1 1 U2 20 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 10 SOUTH MAIN STREET, PENNINGTON, NJ 08534 USA SN 0013-4651 J9 J ELECTROCHEM SOC JI J. Electrochem. Soc. PD DEC PY 1998 VL 145 IS 12 BP 4148 EP 4159 DI 10.1149/1.1838929 PG 12 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA 141YG UT WOS:000077171500019 ER PT J AU Neudecker, BJ Zuhr, RA Robertson, JD Bates, JB AF Neudecker, BJ Zuhr, RA Robertson, JD Bates, JB TI Lithium manganese nickel oxides Li-x(MnyNi1-y)(2-x)O-2 - II. Electrochemical studies on thin-film batteries SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID X-RAY-DIFFRACTION; M = LI; CRYSTAL-STRUCTURE; CATION DISTRIBUTION; CELLS; ELECTROLYTE; LIXCOO2; CATHODE; LIMN2O4; LINIO2 AB In a lithium thin-film battery, the reversible discharge capacity of a Li1.12Mn0.44Ni0.44O2 cathode deposited by rf magnetron sputtering and postannealed at 750 degrees C under O-2 could be increased by 80% to 136 mu Ah/mg when cycled between 4.8-2.5 V instead of 4.2-2.5 V. An 82 atom % Li1.03Mn0.42Ni0.55O2/18 atom % Li2O (14 vol %) cathode prepared from a rf magnetron sputter.-deposited film that was annealed at 700 degrees C under N-2 supplied a reversible discharge capacity of 146 mu Ah/mg between 5.3-1.5V. For a given lithium concentration in the cathode during cycling, the magnitude of the chemical potential of sites on the lithium layers (3a sites) in both rhombohedral cathode phases decreased whenever the charge cutoff voltage was raised. This thermodynamic change is attributed to the migration of transition metal ions from the 3b layer sites to vacancies on the lithium layers at high potentials. These transition metal ions also explain the kinetic limitations the cathodes exhibited at higher current densities. Only one rhombohedral phase could be detected by ex situ X-ray diffraction (XRD) measurements over the voltage range 4.6-1.5 V. At 1.5 V, however, possible additional phases might have been present but not detectable due to their low concentration and/or their X-ray amorphousness. The maximum valence state of the transition metal ions of +4 was reached in rhombohedral LixMn0.44Ni0.44O2 at 4.6 V where about 0.4 Li' per formula units remained on the Lithium layers. Such a high lithium concentration between the MO, slabs (M = metal ion on 3b layer sites) prevented the phase from developing a unit cell. with the extremely small c axis parameter found for "NiO2" and CoO2 and is believed to be an important prerequisite for the good cycle stability of LixMn0.44Ni0.44O2 between 4.8-2.5 V. C1 Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Univ Kentucky, Dept Chem, Lexington, KY 40502 USA. RP Neudecker, BJ (reprint author), Oak Ridge Natl Lab, Div Solid State, POB 2008, Oak Ridge, TN 37831 USA. NR 48 TC 30 Z9 31 U1 3 U2 20 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 10 SOUTH MAIN STREET, PENNINGTON, NJ 08534 USA SN 0013-4651 J9 J ELECTROCHEM SOC JI J. Electrochem. Soc. PD DEC PY 1998 VL 145 IS 12 BP 4160 EP 4168 DI 10.1149/1.1838930 PG 9 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA 141YG UT WOS:000077171500020 ER PT J AU Armstrong, TR Stevenson, JW Hasinska, K McCready, DE AF Armstrong, TR Stevenson, JW Hasinska, K McCready, DE TI Synthesis and properties of mixed lanthanide chromite perovskites SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID ELECTRICAL-CONDUCTIVITY; DEFECT STRUCTURE; TRANSPORT; BEHAVIOR; YCRO3; OXIDE AB Calcium-substituted lanthanum chromites were synthesized using a mixed lanthanide precursor composed primarily of La, Nd, Cc, and Pr The thermal and electrical properties of these materials were measured and compared to similar chromites synthesized with lanthanum nitrate. The presence of Nd and Pr in the chromite resulted in a lowering of the thermal expansion coefficient and an increase in the temperature necessary to attain full density. Arrhenius plots of electrical conductivity were nonlinear with an inflection at temperatures between 625 and 750 degrees C, indicating an increase in the carrier concentration with temperature. The increase in carrier concentration was consistent;with the reduction of Ce4+ to Ce3+, resulting in a corresponding increase in Cr4+ in order to preserve electrical neutrality. The presence of both tri- and tetravalent Cc was substantiated using dilatometry measurements and X-ray photoelectron spectroscopy. The mixed lanthanide precursor is a possible low cost alternative for the synthesis of rare earth chromites for applications such as interconnects in solid oxide fuel cells. C1 Pacific NW Lab, Dept Chem & Mat Sci, Richland, WA 99352 USA. RP Armstrong, TR (reprint author), Pacific NW Lab, Dept Chem & Mat Sci, POB 999, Richland, WA 99352 USA. NR 36 TC 21 Z9 21 U1 0 U2 4 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 10 SOUTH MAIN STREET, PENNINGTON, NJ 08534 USA SN 0013-4651 J9 J ELECTROCHEM SOC JI J. Electrochem. Soc. PD DEC PY 1998 VL 145 IS 12 BP 4282 EP 4289 DI 10.1149/1.1838952 PG 8 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA 141YG UT WOS:000077171500042 ER PT J AU Bennett, JG Haberman, KS Johnson, JN Asay, BW Henson, BF AF Bennett, JG Haberman, KS Johnson, JN Asay, BW Henson, BF TI A constitutive model for the non-shock ignition and mechanical response of high explosives SO JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS LA English DT Article DE microcracking; chemical-mechanical processes; constitutive behaviour; finite elements; energetic materials ID HOT-SPOT IGNITION AB An understanding of the non-shock ignition properties of energetic particulate composite materials, "high explosives" such as PBX-9501 is an important part of the safety assessments for conventional handling (transportation, storage, etc.) of weapons systems including assembly operations. This paper develops and demonstrates the use of a numerical constitutive model for PBX-9501 that includes viscoelastic response, statistical fracture mechanics, and an ignition hot-spot mechanism. The intent is that this model can be used in safety analyses involving accidents to prevent undesirable dispersion of Pu. The parameters have been determined that will predict the mechanical response and ignition/non-ignition of a set of experiments that have explored the non-shock properties of this material. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87544 USA. RP Bennett, JG (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87544 USA. NR 15 TC 58 Z9 73 U1 1 U2 16 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0022-5096 J9 J MECH PHYS SOLIDS JI J. Mech. Phys. Solids PD DEC PY 1998 VL 46 IS 12 BP 2303 EP 2322 DI 10.1016/S0022-5096(98)00011-8 PG 20 WC Materials Science, Multidisciplinary; Mechanics; Physics, Condensed Matter SC Materials Science; Mechanics; Physics GA 146GD UT WOS:000077420200003 ER PT J AU Sucha, G Chemla, DS Bolton, SR AF Sucha, G Chemla, DS Bolton, SR TI Effects of cavity topology on the nonlinear dynamics of additive-pulse mode-locked lasers SO JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS LA English DT Article ID HIGH-ORDER SOLITONS; SEMICONDUCTOR-LASERS; RING LASER; LOCKING; GENERATION AB We study the effect of cavity topology on the nonlinear dynamics of additive-pulse mode-locked (APM) lasers configured in the Fabry-Perot and Michelson geometries. In experiments the Fabry-Perot laser often exhibits such behaviors as period doubling and quasiperiodicity as the nonlinearity is increased, whereas the Michelson APM (M-APM) exhibits none of these effects. Numerical studies confirm that the M-APM appears to be more resistant to such behavior and thus is more tolerant to excessive nonlinearity in the control cavity. Using the concepts of intensity- and phase-dependent two-beam and multiple-beam interference, we obtain a general empirical rule connecting cavity topology to pulse train instabilities for fast saturable absorber mode-locked lasers employing coupled cavities. (C) 1998 Optical Society of America. [S0740-3224(98)01910-9]. OCIS codes: 140.1540, 140.4050, 140.1700, 320.7090, 320.7110. C1 IMRA Amer, Ann Arbor, MI 48105 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Williams Coll, Dept Phys, Williamstown, MA 01267 USA. RP Sucha, G (reprint author), IMRA Amer, 1044 Woodridge Ave, Ann Arbor, MI 48105 USA. NR 24 TC 10 Z9 10 U1 0 U2 0 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0740-3224 J9 J OPT SOC AM B JI J. Opt. Soc. Am. B-Opt. Phys. PD DEC PY 1998 VL 15 IS 12 BP 2847 EP 2853 DI 10.1364/JOSAB.15.002847 PG 7 WC Optics SC Optics GA 147HC UT WOS:000077482400005 ER PT J AU Fischer, RU Congdon, JD Difonzo, CD Aho, JM AF Fischer, RU Congdon, JD Difonzo, CD Aho, JM TI Lipid and reproductive cycles of bluegills (Lepomis macrochirus) exposed to 35 years of elevated environmental temperatures SO JOURNAL OF THERMAL BIOLOGY LA English DT Article DE cooling reservoir; lipid cycles of bluegill from a heated and normothermic ponds; reproduction; thermal environment ID THERMOREGULATION; RESERVOIR; STORAGE AB 1.. We studied bluegills to compare how thermal perturbation affected lipid dynamics and reproductive cycles of fish from heated (Pond C) and normothermic (Par Pond) sites. 2. Bodies of bluegills contained over 90%, and gonads and livers 10% of the non-polar lipids. 3. Overall, the percent body lipids of bluegills from the heated pond was twice as high (12.4%) as that of Par Pond bluegills (6.6%). 4. During a prolonged reactor down period, when both ponds were normothermic, body lipids of bluegills from Pond C and Par Pond increased at a rate of approximately 3 and 1% of body mass per week, respectively. 5. Juveniles from Pond C had higher percent stored lipids than did adult males or females. 6. Lipid cycling in Par Pond bluegills was seasonal, whereas Pond C bluegill lipid cycles corresponded to long reactor down periods. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Eastern Illinois Univ, Dept Zool, Charleston, IL 61920 USA. Savannah River Ecol Lab, Aiken, SC 29802 USA. Michigan State Univ, Dept Entomol, E Lansing, MI 48824 USA. Auburn Univ, Dept Biol, Montgomery, AL 36117 USA. RP Fischer, RU (reprint author), Eastern Illinois Univ, Dept Zool, Charleston, IL 61920 USA. NR 28 TC 6 Z9 6 U1 0 U2 2 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0306-4565 J9 J THERM BIOL JI J. Therm. Biol. PD DEC PY 1998 VL 23 IS 6 BP 359 EP 367 DI 10.1016/S0306-4565(98)00026-6 PG 9 WC Biology; Zoology SC Life Sciences & Biomedicine - Other Topics; Zoology GA 155BZ UT WOS:000077927200006 ER PT J AU Fincke, J AF Fincke, J TI Progress on diagnostics and instrumentation in the thermal spray process SO JOURNAL OF THERMAL SPRAY TECHNOLOGY LA English DT Editorial Material C1 Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. RP Fincke, J (reprint author), Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. NR 0 TC 0 Z9 0 U1 1 U2 1 PU ASM INTERNATIONAL PI MATERIALS PARK PA SUBSCRIPTIONS SPECIALIST CUSTOMER SERVICE, MATERIALS PARK, OH 44073-0002 USA SN 1059-9630 J9 J THERM SPRAY TECHN JI J. Therm. Spray Technol. PD DEC PY 1998 VL 7 IS 4 BP 447 EP 447 DI 10.1007/s11666-998-0042-z PG 1 WC Materials Science, Coatings & Films SC Materials Science GA 147UZ UT WOS:000077516700001 ER PT J AU Varacalle, DJ Zeek, DP Zanchuck, V Sampson, E Couch, KW Benson, D Cox, GS AF Varacalle, DJ Zeek, DP Zanchuck, V Sampson, E Couch, KW Benson, D Cox, GS TI Experimental studies of twin-wire electric arc sprayed zinc/aluminum alloy coatings SO JOURNAL OF THERMAL SPRAY TECHNOLOGY LA English DT Article DE box; characterization; coatings; corrosion resistance; regression analysis; twin-wire; 85/15 AB An experimental study of twin-wire electric are spraying of zinc/aluminum alloy coatings demonstrates the suitability of the systems for anticorrosion applications. Experiments were conducted using Box-type, fractional-factorial designs. The process parameters that were varied include nozzle diameter, current, spray distance, and system pressure. The experiments were designed to display the range of processing conditions and their effect on the coating. The coatings were characterized with bond strength and deposition efficiency tests and optical metallography. Coating characteristics were quantified with respect to roughness, porosity, thickness, bond strength, and microstructure. Performance evaluation of the coatings was quantified with accelerated corrosion testing. A parameter-property-performance relationship has been developed for each material system. This paper presents the results of material systems 85Zn/15Al and 70Zn/30Al. C1 Idaho Natl Engn Lab, Idaho Falls, ID 83415 USA. Tafa Inc, Concord, NH 03301 USA. Protech Lab Corp, Cincinnati, OH 45241 USA. ITI Anticorros Inc, Houston, TX 77036 USA. RP Varacalle, DJ (reprint author), Idaho Natl Engn Lab, Idaho Falls, ID 83415 USA. NR 5 TC 11 Z9 11 U1 1 U2 7 PU ASM INTERNATIONAL PI MATERIALS PARK PA SUBSCRIPTIONS SPECIALIST CUSTOMER SERVICE, MATERIALS PARK, OH 44073-0002 USA SN 1059-9630 J9 J THERM SPRAY TECHN JI J. Therm. Spray Technol. PD DEC PY 1998 VL 7 IS 4 BP 513 EP 520 DI 10.1361/105996398770350738 PG 8 WC Materials Science, Coatings & Films SC Materials Science GA 147UZ UT WOS:000077516700008 ER PT J AU Neiser, RA Smith, MF Dykhuizen, RC AF Neiser, RA Smith, MF Dykhuizen, RC TI Oxidation in wire HVOF-sprayed steel SO JOURNAL OF THERMAL SPRAY TECHNOLOGY LA English DT Article DE Auger spectroscopy; HVOF; oxidation AB It is widely held that most oxidation in thermally sprayed coatings occurs on the surface of the droplet after it has flattened. Evidence in this paper suggests that, for the conditions studied here, oxidation of the top surface of flattened droplets is not the dominant oxidation mechanism. In this study, a mild steel wire (AISI 1025) was sprayed using a high-velocity oxy-fuel (HVOF) torch onto copper and aluminum substrates, Ion milling and Auger spectroscopy were used to examine the distribution of oxides within individual splats, Conventional metallographic analysis was also used to study oxide distributions within coatings that were sprayed under the same conditions, An analytical model for oxidation of the exposed surface of a splat is presented. Based on literature data, the model assumes that diffusion of iron through a solid FeO layer is the rate limiting factor in forming the oxide on the top surface of a splat. An FeO layer only a few nanometers thick is predicted to form on the splat surface as it cools. However, experimental evidence shows that the oxide layers are typically 100x thicker than the predicted value. These thick oxide layers are not always observed on the top surface of a splat, Indeed, in some instances the oxide layer is on the bottom, and the metal is on the top. The observed oxide distributions are more consistently explained if most of the oxide forms before the droplets impact the substrate. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Smith, MF (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 19 TC 56 Z9 59 U1 0 U2 3 PU ASM INTERNATIONAL PI MATERIALS PARK PA SUBSCRIPTIONS SPECIALIST CUSTOMER SERVICE, MATERIALS PARK, OH 44073-0002 USA SN 1059-9630 J9 J THERM SPRAY TECHN JI J. Therm. Spray Technol. PD DEC PY 1998 VL 7 IS 4 BP 537 EP 545 DI 10.1361/105996398770350765 PG 9 WC Materials Science, Coatings & Films SC Materials Science GA 147UZ UT WOS:000077516700011 ER EF