FN Thomson Reuters Web of Science™ VR 1.0 PT J AU Otto, WH Burton, SD Carper, WR Larive, CK AF Otto, WH Burton, SD Carper, WR Larive, CK TI Examination of Cadmium(II) complexation by the suwannee river fulvic acid using Cd-113 NMR relaxation measurements SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Article ID SPIN-LATTICE RELAXATION; CORRELATION TIMES; BINDING; CD AB Aquatic and terrestrial fulvic acids are environmentally important because they affect the bioavailability and transport of metal ions. Prior studies demonstrated that COO binds to the oxygen containing functional groups of fulvic acids. The complexation of Cd(II) is further investigated in this study using Cd-113 NMR relaxation measurements for solutions of the Suwannee River fulvic acid (SRFA). Spin-lattice (T-1) and spin-spin (T-2) relaxation times are measured over a range of Cd(II):SRFA ratios. The results clearly indicate two types of Cd(II) binding sites for the SRFA. A series of model ligands was also examined to gain further understanding of the two types of binding motifs present in the fulvic acid. The results for a model compound containing several carboxylate functionalities in near proximity correspond very closely to the results obtained for the strong binding sites of the Cd(II)-SRFA complexes. C1 Univ Kansas, Dept Chem, Lawrence, KS 66045 USA. Wichita State Univ, Dept Chem, Wichita, KS 67260 USA. Pacific NW Natl Lab, Richland, WA 99352 USA. RP Larive, CK (reprint author), Univ Kansas, Dept Chem, Lawrence, KS 66045 USA. RI Larive, Cynthia/E-4640-2012; OI Larive, Cynthia/0000-0003-3458-0771 NR 25 TC 14 Z9 14 U1 0 U2 11 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 2001 VL 35 IS 24 BP 4900 EP 4904 DI 10.1021/es0108032 PG 5 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 502UF UT WOS:000172760600028 PM 11775168 ER PT J AU Gaffney, JS Marley, NA AF Gaffney, JS Marley, NA TI Comment on "Environmental implications on the oxygenation of gasoline with ethanol in the metropolitan area of Mexico City" SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Letter C1 Argonne Natl Lab, Div Environm Res, Argonne, IL 60439 USA. RP Gaffney, JS (reprint author), Argonne Natl Lab, Div Environm Res, Argonne, IL 60439 USA. NR 8 TC 6 Z9 6 U1 0 U2 5 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 2001 VL 35 IS 24 BP 4957 EP 4958 DI 10.1021/es0110832 PG 2 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 502UF UT WOS:000172760600039 PM 11775179 ER PT J AU Sigurdsson, S Van Komen, S Bussen, W Schild, D Albala, JS Sung, P AF Sigurdsson, S Van Komen, S Bussen, W Schild, D Albala, JS Sung, P TI Mediator function of the human Rad51B-Rad51C complex in Rad51/RPA-catalyzed DNA strand exchange SO GENES & DEVELOPMENT LA English DT Article DE DNA double-strand break repair; tumor suppression ID REPLICATION PROTEIN-A; HUMAN RAD51 PROTEIN; SACCHAROMYCES-CEREVISIAE; BINDING-PROTEIN; HRP-A; RECOMBINATION; REPAIR; RECA; STIMULATION; POLARITY AB Five Rad51-like proteins, referred to as Rad51 paralogs, have been described in vertebrates. We show that two of them, Rad51B and Rad51C, are associated in a stable complex. Rad51B-Rad51C complex has ssDNA binding and ssDNA-stimulated ATPase activities. We also examined the functional interaction of Rad51B-Rad51C with Rad51 and RPA. Even though RPA enhances Rad51-catalyzed DNA joint formation via removal of secondary structure in the ssDNA substrate, it can also compete with Rad51 for binding to the substrate, leading to suppressed reaction efficiency. The competition by RPA for substrate binding can be partially alleviated by Rad51B-Rad51C. This recombination mediator function of Rad51B-Rad51C is likely required for the assembly of the Rad51-ssDNA nucleoprotein filament in vivo. C1 Univ Texas Hlth Sci Ctr, Dept Mol Med, Inst Biotechnol, San Antonio, TX 78245 USA. Lawrence Berkeley Natl Lab, Life Sci Div, Berkeley, CA 94720 USA. Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, Livermore, CA 94551 USA. RP Sung, P (reprint author), Univ Texas Hlth Sci Ctr, Dept Mol Med, Inst Biotechnol, San Antonio, TX 78245 USA. RI Sigurdsson, Stefan/L-9820-2015 OI Sigurdsson, Stefan/0000-0002-5284-0058 FU NCI NIH HHS [R55 CA081019, CA81019-01, P01 CA081020, P01CA81020, R01 CA081019]; NIEHS NIH HHS [ES07061, R01 ES007061]; NIGMS NIH HHS [GM30990, GM57814, R01 GM057814] NR 33 TC 146 Z9 152 U1 0 U2 1 PU COLD SPRING HARBOR LAB PRESS PI PLAINVIEW PA 1 BUNGTOWN RD, PLAINVIEW, NY 11724 USA SN 0890-9369 J9 GENE DEV JI Genes Dev. PD DEC 15 PY 2001 VL 15 IS 24 BP 3308 EP 3318 DI 10.1101/gad.935501 PG 11 WC Cell Biology; Developmental Biology; Genetics & Heredity SC Cell Biology; Developmental Biology; Genetics & Heredity GA 504WP UT WOS:000172879200009 PM 11751636 ER PT J AU Sanderson, TR Marsden, RG Tranquille, C Balogh, A Forsyth, RJ Goldstein, BE Gosling, JT Harvey, KL AF Sanderson, TR Marsden, RG Tranquille, C Balogh, A Forsyth, RJ Goldstein, BE Gosling, JT Harvey, KL TI The influence of the Sun's magnetic field on energetic particles at high heliospheric latitudes SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID SECTOR STRUCTURE; SOLAR-WIND; ULYSSES AB The first passage of the Ulysses spacecraft to high latitudes was during the declining phase of solar cycle 22. The recent second passage to high latitudes was close to the maximum of solar cycle 23. The axis of the dipolar component of the Sun's magnetic field was close to 90 degrees from the spin axis, and the coronal neutral line extended up to high latitudes. A variable but generally slow solar wind was observed all the way up to the highest latitudes reached by Ulysses, as was the sector structure of the magnetic field. The high-latitude heliosphere was populated with intensities of energetic particles with energies around 1 MeV several orders of magnitude above background. We show how the changes in the Sun's magnetic field, the coronal holes, and the configuration of the heliosphere could be responsible for the differences between particle observations in the two orbits. C1 European Space Agcy, Estec, Dept Space Sci, NL-2200 AG Noordwijk, Netherlands. Univ London Imperial Coll Sci Technol & Med, Blackett Lab, London, England. CALTECH, Jet Prop Lab, Pasadena, CA USA. Los Alamos Natl Lab, Los Alamos, NM USA. Solar Phys Res Corp, Tucson, AZ USA. RP Sanderson, TR (reprint author), European Space Agcy, Estec, Dept Space Sci, NL-2200 AG Noordwijk, Netherlands. NR 11 TC 4 Z9 4 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 2001 VL 28 IS 24 BP 4525 EP 4528 DI 10.1029/2001GL013146 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 507KA UT WOS:000173025400004 ER PT J AU Widlowski, JL Pinty, B Gobron, N Verstraete, MM Davis, AB AF Widlowski, JL Pinty, B Gobron, N Verstraete, MM Davis, AB TI Characterization of surface heterogeneity detected at the MISR/TERRA subpixel scale. SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID STRATOCUMULUS; FRACTALS; RAIN AB Vegetation structure can have a significant impact on the degree of anisotropy in the reflected radiation field. With the appropriate characterization of these effects, the analysis of multiangular data, such as provided by the Multi-angle Imaging SpectroRadiometer (MISR) instrument on board TERRA, can yield statistical information about the type of surface heterogeneity that exists at the subpixel scale. C1 Joint Res Ctr, Space Applicat Inst, GVM Unit, I-21020 Ispra, Italy. Los Alamos Natl Lab, Space & Remote Sensing Grp, Los Alamos, NM 87545 USA. RP Widlowski, JL (reprint author), Joint Res Ctr, Space Applicat Inst, GVM Unit, TP 440, I-21020 Ispra, Italy. OI Verstraete, Michel/0000-0003-0968-8721 NR 12 TC 34 Z9 34 U1 0 U2 1 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 2001 VL 28 IS 24 BP 4639 EP 4642 DI 10.1029/2001GL013490 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 507KA UT WOS:000173025400033 ER PT J AU Kammler, DR Mason, TO Young, DL Coutts, TJ Ko, D Poeppelmeier, KR Williamson, DL AF Kammler, DR Mason, TO Young, DL Coutts, TJ Ko, D Poeppelmeier, KR Williamson, DL TI Comparison of thin film and bulk forms of the transparent conducting oxide solution Cd1+xIn2-2xSnxO4 SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID ELECTRICAL-PROPERTIES; CD2SNO4; CDIN2O4; RADII; CDO AB Physical and structural properties of thin films prepared via rf magnetron sputtering of the transparent conducting oxide spinel Cd1+xIn2-2xSnxO4 are compared to those reported for bulk specimens (prepared via high-temperature solid state reaction at 1175 degreesC). Optical band gaps measured on thin films of Cd1+xIn2-2xSnxO4 were 3.5, 3.70, and 3.65 eV for x=0.15, 0.45, and 0.70, which where 0.57, 0.94, and 0.95 eV higher than their bulk counterparts. Thin film Seebeck coefficients were -18.0, -15.5, and -15.5 muV/K for x=0.15, 0.45, and 0.70, respectively, which were 27, 24, and 19 muV/K smaller in magnitude than their bulk counterparts. Sn-Mossbauer spectroscopy revealed isomer shifts that averaged 0.2 mm/s for both bulk and thin films specimens. The presence of quadrupole splitting, which averaged near 0.48 mm/s for film specimens and 0.39 mm/s for bulk specimens, suggests that Sn+4 in all specimens is in octahedral coordination. The difference in quadrupole splitting suggests that thin films have a different cation distribution than their bulk counterparts. The effective mass at the base of the conduction band, measured via the method-of-four-coefficients, was found to be 0.25, 0.18, 0.21, and 0.22 m(e) for x equal to 0.15, 0.45, 0.70, and 1.0, respectively. A model that explains the changes in optical gap and thermopower as a result of differences in the fundamental band gap (resulting from a changing cation distribution), conduction band curvature, and carrier density is presented. (C) 2001 American Institute of Physics. C1 Northwestern Univ, Dept Mat Sci & Engn, Evanston, IL 60208 USA. Northwestern Univ, Ctr Mat Res, Evanston, IL 60208 USA. Natl Renewable Energy Lab, Golden, CO 80401 USA. Northwestern Univ, Dept Chem, Evanston, IL 60208 USA. Colorado Sch Mines, Dept Phys, Golden, CO 80401 USA. RP Mason, TO (reprint author), Northwestern Univ, Dept Mat Sci & Engn, Evanston, IL 60208 USA. RI Mason, Thomas/B-7528-2009 NR 31 TC 37 Z9 37 U1 0 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 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD DEC 15 PY 2001 VL 90 IS 12 BP 5979 EP 5985 DI 10.1063/1.1410882 PG 7 WC Physics, Applied SC Physics GA 498BK UT WOS:000172489800024 ER PT J AU Herrera-Gomez, A Aguirre-Tostado, FS Sun, Y Pianetta, P Yu, Z Marshall, D Droopad, R Spicer, WE AF Herrera-Gomez, A Aguirre-Tostado, FS Sun, Y Pianetta, P Yu, Z Marshall, D Droopad, R Spicer, WE TI Photoemission from the Sr/Si(001) interface SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID JET VAPOR-DEPOSITION; THIN-FILMS; CAPACITORS; SURFACE; SILICON; OXIDES; SR AB The growth of Sr on n-type Si(001) was studied in detail for coverages between 0 and 1 monolayer (ML) using core level photoemission spectroscopy. In a similar manner, the Sr saturation coverage was studied in the 600-925 degreesC temperature range. Data analysis was carried out by a method that allows accurate determination of the band-bending shifts. Using this method it is possible to pinpoint the formation and destruction of chemical species from bungled core level photoemission data without needing to know details of the chemical composition of the spectra. Through this analysis it was established that the interaction between Sr and Si breaks down the binding energy difference between upward and downward Si dimer atoms. In addition, it was found that the saturation coverage exhibits a clear plateau at 1 ML around 650 degreesC, and a slope change at 1/3 ML around 850 degreesC. The surface band bending suffers a discontinuous increase as the Sr coverage surpasses 1/2 s ML and as the low energy electron diffraction symmetry changes from [2x3] to [2x1]. (C) 2001 American Institute of Physics. C1 CINVESTAV Queretaro, Realll De Juriqulla 76230, Queretaro, Mexico. CINVESTAV Fis, Zacatenco 07360, DF, Mexico. Stanford Synchrotron Radiat Lab, Menlo Pk, CA 94025 USA. Motorola Inc, Phys Sci Res Labs, Tempe, AZ 85284 USA. RP Herrera-Gomez, A (reprint author), CINVESTAV Queretaro, Libramiento Norponiente 2000, Realll De Juriqulla 76230, Queretaro, Mexico. NR 13 TC 30 Z9 30 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 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD DEC 15 PY 2001 VL 90 IS 12 BP 6070 EP 6072 PG 3 WC Physics, Applied SC Physics GA 498BK UT WOS:000172489800039 ER PT J AU Sugimoto, M Sakaki, S Sakanoue, K Newton, MD AF Sugimoto, M Sakaki, S Sakanoue, K Newton, MD TI Theory of emission state of tris(8-quinolinolato)aluminum and its related compounds SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID ORGANIC ELECTROLUMINESCENT DEVICES; MOLECULAR-ORBITAL METHODS; LIGHT-EMITTING DEVICES; GAUSSIAN-TYPE BASIS; EXCITED-STATES; METAL-COMPLEX; ALUMINUM; SPECTRA; RU(PHEN)(3)(2+); DELOCALIZATION AB Fluorescence of fac-AlQ(3) (Q=8-quinolinolato), mer-AlQ(3), mer-Al(mQ)(3) (mQ=4-methyl-8-quinolinolato), and BeQ(2) were investigated with electronic structure calculations. The molecular structure of the first singlet excited state (the emission state) was optimized with the ab initio "configuration interaction with single excitations" (CIS) method. Ab initio CIS and semiempirical "Zerner's intermediate neglect of differential overlap" (ZINDO) methods were used to calculate the emission energies (DeltaE) and also the corresponding absorption energies. Although the ab initio CIS method overestimated the experimental value of DeltaE by 1.09-1.16 eV, the ZINDO method reproduced it to a reasonable accuracy (within 0.26 eV). The optimized excited-state structure has an interesting feature in that one of the equivalent ligands distorts appreciably, while the thers keep their ground-state structures. As a result the highest occupied and the lowest unoccupied molecular orbitals (HOMO and LUMO) are localized on the distorted ligand. Since the excited state is characterized as the HOMO-LUMO transition, the emission from AlQ(3) (and its analogues) directly reflects that of the ligand. In order to analyze this intrigung excited-state structure, exciton transfer theory was applied, where the exciton coupling between ligands and the structural relaxation of the ligand upon excitation were taken into account. By examining these two factors for BeQ(2), it is shown that the exciton localization results from weak exciton coupling and/or large structural relaxation energy. (C) 2001 American Institute of Physics. C1 Kumamoto Univ, Fac Engn, Dept Appl Chem & Biochem, Kumamoto 8608555, Japan. Kyushu Matsushita Elect Co Ltd, Corp Engn Div, Res & Dev Lab, Fukuoka 8128531, Japan. Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. RP Sugimoto, M (reprint author), Kumamoto Univ, Fac Engn, Dept Appl Chem & Biochem, Kumamoto 8608555, Japan. NR 43 TC 41 Z9 42 U1 0 U2 3 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 15 PY 2001 VL 90 IS 12 BP 6092 EP 6097 DI 10.1063/1.1415059 PG 6 WC Physics, Applied SC Physics GA 498BK UT WOS:000172489800042 ER PT J AU Levin, EM Pecharsky, VK Gschneidner, KA AF Levin, EM Pecharsky, VK Gschneidner, KA TI Real and imaginary components of the alternating current magnetic susceptibility of RAl2 (R=Gd, Dy, and Er) in the ferromagnetic region SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID CUBIC INTERMETALLIC COMPOUNDS; AC SUSCEPTIBILITY; SINGLE-CRYSTAL; FIELD AB The real (chi'(ac)) and imaginary (chi " (ac)) components of the ac magnetic susceptibility of the polycrystalline GdAl2, DyAl2, and ErAl2 have been measured as functions of temperature, ac and bias dc magnetic field amplitude, and ac magnetic field frequency. Both chi'(ac) and chi " (ac) of the ferromagnetic DyAl2 and ErAl2 are strongly dependent on the ac magnetic field parameters, especially when compared with those of the ferromagnetic GdAl2. The observed behavior of the ac magnetic susceptibility is determined mainly by the domain dynamics, rather than by a change of the exchange interactions below Curie temperature. (C) 2001 American Institute of Physics. C1 Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Dept Mat Sci & Engn, Ames, IA 50011 USA. RP Pecharsky, VK (reprint author), Iowa State Univ Sci & Technol, Ames Lab, 242 Spedding Hall, Ames, IA 50011 USA. NR 21 TC 51 Z9 51 U1 1 U2 9 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 15 PY 2001 VL 90 IS 12 BP 6255 EP 6262 DI 10.1063/1.1415056 PG 8 WC Physics, Applied SC Physics GA 498BK UT WOS:000172489800069 ER PT J AU Wright, AF AF Wright, AF TI Interaction of hydrogen with nitrogen interstitials in wurtzite GaN SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID TOTAL-ENERGY CALCULATIONS; WAVE BASIS-SET; NATIVE DEFECTS; MOLECULAR-DYNAMICS; GALLIUM NITRIDE; MG; ACTIVATION; METALS; STATE AB First-principles techniques are used to investigate the interaction of hydrogen with nitrogen interstitials in wurtzite GaN. The calculations reveal that hydrogen can either compensate an interstitial by donating an electron to an interstitial acceptor level, or passivate the interstitial by forming a hydrogen-interstitial complex. Nitrogen interstitials can bind up to three hydrogen atoms and hydrogen removal energies are computed as a function of the number of hydrogen atoms. Removal energies are found to depend strongly on the Fermi level, and hydrogen-interstitial complexes are predicted to be unstable in n-type GaN. Frequencies are computed for hydrogen vibrations and compared with previously reported infrared absorption measurements on hydrogen-implanted GaN. (C) 2001 American Institute of Physics. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. EM afwright@sandia.gov NR 24 TC 18 Z9 18 U1 2 U2 5 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 0021-8979 EI 1089-7550 J9 J APPL PHYS JI J. Appl. Phys. PD DEC 15 PY 2001 VL 90 IS 12 BP 6526 EP 6532 DI 10.1063/1.1400099 PG 7 WC Physics, Applied SC Physics GA 498BK UT WOS:000172489800110 ER PT J AU Pushkarsky, MB Mann, AM Yeston, JS Moore, CB AF Pushkarsky, MB Mann, AM Yeston, JS Moore, CB TI Electronic spectroscopy of jet-cooled vinyl radical SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID ABSORPTION-SPECTRUM; RATE CONSTANTS; AB-INITIO; PHOTODISSOCIATION; C2H3; STATE AB The spectra of the (X) over tilde (2)A'-(A) over tilde (2)A" electronic transition of jet-cooled vinyl radical, C2H3, and its partially deuterated isotopomer, CD2CH, have been obtained via action spectroscopy. The appearance of the H or D fragment was monitored via 1+1' resonance enhanced multiphoton ionization through the Lyman-alpha transition. The vibrational structure of the (A) over tilde (2)A" state was fully resolved and analyzed. The experimental vibrational frequencies agree well with ab initio calculations. The simulation of the rotational structure of several bands reinforces vibrational assignments. (C) 2001 American Institute of Physics. C1 Ohio State Univ, Dept Chem, Laser Spect Facil, Columbus, OH 43210 USA. Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA. RP Moore, CB (reprint author), Ohio State Univ, Dept Chem, Laser Spect Facil, Columbus, OH 43210 USA. NR 20 TC 24 Z9 25 U1 3 U2 6 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 2001 VL 115 IS 23 BP 10738 EP 10744 DI 10.1063/1.1416495 PG 7 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 498WF UT WOS:000172536000020 ER PT J AU Rodriguez, JA Jirsak, T Gonzalez, L Evans, J Perez, M Maiti, A AF Rodriguez, JA Jirsak, T Gonzalez, L Evans, J Perez, M Maiti, A TI Reaction of SO2 with pure and metal-doped MgO: Basic principles for the cleavage of S-O bonds SO JOURNAL OF CHEMICAL PHYSICS LA English DT Review ID TOTAL-ENERGY CALCULATIONS; SOLID-SOLUTION CATALYSTS; BAND-GAP SIZE; ELECTRONIC-STRUCTURE; AB-INITIO; OXIDE SURFACES; CHEMICAL-REACTIVITY; TIO2(110) SURFACE; MGO(100) SURFACE; MAGNESIUM-OXIDE AB Synchrotron-based high-resolution photoemission, x-ray absorption near-edge spectroscopy, and first-principles density-functional calculations are used to examine the interaction of SO2 with pure and modified surfaces of magnesium oxide. On a MgO(100) single crystal, SO2 reacts with O centers to form SO3 and SO4 species. The bonding interactions with the Mg cations are weak and do not lead to cleavage of S-O bonds. An identical result is found after adsorbing SO2 on pure stoichiometric powders of MgO and other oxides (TiO2, Cr2O3, Fe2O3, NiO, CuO, ZnO, V2O5, CeO2, BaO). In these systems, the occupied cations bands are too stable for effective bonding interactions with the LUMO of SO2. To activate an oxide for S-O bond cleavage, one has to create occupied metal states above the valence band of the oxide. DF calculations predict that in the presence of these "extra" electronic states the adsorption energy of SO2 should increase, and there should be a significant oxide --> SO2(LUMO) charge transfer that facilitates the cleavage of the S-O bonds. In this article, we explore three different approaches (formation of O vacancies, promotion with alkali metals, and doping with transition metals) that lead to the activation of SO2 and S-O bond breaking on MgO and oxides in general. Basic principles for a rational design of catalysts with a high efficiency for the destruction of SO2 are presented. (C) 2001 American Institute of Physics. C1 Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. Cent Univ Venezuela, Fac Ciencias, Caracas 1020A, Venezuela. Accelrys Inc, San Diego, CA 92121 USA. RP Rodriguez, JA (reprint author), Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. NR 104 TC 41 Z9 41 U1 3 U2 38 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 2001 VL 115 IS 23 BP 10914 EP 10926 DI 10.1063/1.1416683 PG 13 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 498WF UT WOS:000172536000039 ER PT J AU Rose, MK Borg, A Mitsui, T Ogletree, DF Salmeron, M AF Rose, MK Borg, A Mitsui, T Ogletree, DF Salmeron, M TI Subsurface impurities in Pd(111) studied by scanning tunneling microscopy SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID SURFACE; OXYGEN; SEGREGATION; SOLUBILITY; ADSORPTION; DIFFUSION; PALLADIUM; HYDROGEN; METALS; STRAIN AB Low concentrations of three distinct impurity species beneath the Pd(111) surface are studied by STM. The subsurface impurities are distinguished by their image contrast, diffusion properties, and interactions with adsorbed molecules. Isolated subsurface impurities appear at low gap resistance (less than or similar to5 M Omega) as three-fold symmetric modulations of the Pd 1x1 surface corrugation. One impurity type is found to occupy substitutional sites in the layer below the surface. Based on Auger spectroscopy this species is identified as sulfur. The other two species are found to occupy octahedral interstitial sites immediately below the surface layer. Two-dimensional diffusion of the interstitial impurities occurs below room temperature. The onset temperature for diffusion is lowered dramatically in the presence of surface adsorbates. Quantitative measures of the diffusion barriers are consistent with surface facilitated diffusion of interstitial oxygen and carbon atoms. The mobile impurities interact with adsorbed atoms and molecules, limiting surface diffusion, nucleating island growth, and serving as active sites for surface reactions. (C) 2001 American Institute of Physics. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. RP Rose, MK (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RI Ogletree, D Frank/D-9833-2016 OI Ogletree, D Frank/0000-0002-8159-0182 NR 19 TC 60 Z9 60 U1 3 U2 25 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 2001 VL 115 IS 23 BP 10927 EP 10934 DI 10.1063/1.1420732 PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 498WF UT WOS:000172536000040 ER PT J AU Annis, BK Borodin, O Smith, GD Benmore, CJ Soper, AK Londono, JD AF Annis, BK Borodin, O Smith, GD Benmore, CJ Soper, AK Londono, JD TI The structure of a poly(ethylene oxide) melt from neutron scattering and molecular dynamics simulations SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID MODEL MOLECULES; AB-INITIO; POLYETHYLENE; DIFFRACTION AB We have determined the static structure factor for a poly(ethylene oxide) (PEO) melt from neutron scattering and atomistic molecular dynamics simulations. The experimental total structure factors for protonated and deuterated samples were found to be in good agreement with simulation. The calculated partial structure functions facilitate the interpretation of features in the total radial distribution function in the 5-15 Angstrom range and comparison is made with previous work on poly(ethylene). Using hydrogen-deuterium isotope substitution methods, the intermolecular H-H pair distribution function was determined. Unlike a previous comparison for polyethylene, only qualitative agreement between experiment and simulation for the intermolecular H-H pair distribution function was obtained. (C) 2001 American Institute of Physics. C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. Univ Utah, Dept Mat Sci & Engn, Salt Lake City, UT 84112 USA. Univ Utah, Dept Chem & Fuels Engn, Salt Lake City, UT 84112 USA. Argonne Natl Lab, IPNS Div, Argonne, IL 60439 USA. Rutherford Appleton Lab, ISIS Sci Div, Didcot OX11 0QX, Oxon, England. Dupont Co Inc, Expt Stn Lab, Wilmington, DE 19880 USA. RP Annis, BK (reprint author), Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RI Borodin, Oleg/B-6855-2012; OI Borodin, Oleg/0000-0002-9428-5291; Benmore, Chris/0000-0001-7007-7749 NR 25 TC 26 Z9 26 U1 1 U2 12 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 2001 VL 115 IS 23 BP 10998 EP 11003 DI 10.1063/1.1418727 PG 6 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 498WF UT WOS:000172536000047 ER PT J AU Trainor, TP Fitts, JP Templeton, AS Grolimund, D Brown, GE AF Trainor, TP Fitts, JP Templeton, AS Grolimund, D Brown, GE TI Grazing-incidence XAFS study of aqueous Zn(II) sorption on alpha-Al(2)O(3) single crystals SO JOURNAL OF COLLOID AND INTERFACE SCIENCE LA English DT Article ID ABSORPTION FINE-STRUCTURE; METAL-OXIDE SURFACES; PRECIPITATION; ADSORPTION; INTERFACES; PB(II); CO(II); SITES; IDENTIFICATION; SPECTROSCOPY AB Grazing-incidence XAFS spectroscopy was applied to study the sorption of Zn(II) on two crystallographically distinct surfaces of highly polished sapphire single crystals as a simplified analog for metal ion sorption on natural aluminum-(hydr)oxides. Experiments were performed both in situ (in contact with bulk solution) and ex situ in a humidified N(2) atmosphere. The identification of an Al shell at roughly 3 Angstrom in all samples indicates that Zn(II) binds as an inner sphere complex on both the (0001) and (1-102) surfaces. The first shell Zn-O distances of 1.97-1.99 Angstrom suggest that Zn is in fourfold coordination with oxygen in the in situ samples. However, sample drying appears to have induced the formation of polynuclear surface complexes with first shell Zn-O distances closer to values expected for sixfold coordination (2.06-2.07 Angstrom ). The results presented here show that in situ characterization of sorption products on single crystal surfaces using Grazing-incidence XAFS is feasible if solution conditions are chosen carefully. (C) 2001 Elsevier Science. C1 Stanford Univ, Dept Geol & Environm Sci, Stanford, CA 94305 USA. Columbia Univ, Environm Mol Sci Inst, New York, NY 10027 USA. Paul Scherrer Inst, SLS, CH-5232 Villigen, Switzerland. Stanford Synchrotron Radiat Lab, Stanford, CA 94309 USA. RP Trainor, TP (reprint author), Univ Chicago, Consortium Adv Radiat Sources, Bldg 434-A,9700 S Cass Ave, Argonne, IL 60439 USA. EM trainor@cars.uchicago.edu RI Fitts, Jeffrey/J-3633-2012 NR 32 TC 26 Z9 26 U1 1 U2 15 PU ACADEMIC PRESS INC ELSEVIER SCIENCE 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 2001 VL 244 IS 2 BP 239 EP 244 DI 10.1006/jcis.2001.7951 PG 6 WC Chemistry, Physical SC Chemistry GA 502LM UT WOS:000172745100003 ER PT J AU Doss, ED Kumar, R Ahluwalia, RK Krumpelt, M AF Doss, ED Kumar, R Ahluwalia, RK Krumpelt, M TI Fuel processors for automotive fuel cell systems: a parametric analysis SO JOURNAL OF POWER SOURCES LA English DT Article DE fuel processing; fuel cell systems; system modeling; system efficiency AB An autothermally-reformed, gasoline-fueled automotive polymer electrolyte fuel cell (PEFC) system has been modeled and analyzed for the fuel processor and total system performance. The purpose of the study is to identify the influence of various operating parameters on the system performance and to investigate related tradeoff scenarios. Results of steady-state analyses at the design rated power level are presented and discussed. The effects of the following parameters are included in the analysis: operating pressure (3 and 1 atm), reforming temperature (1000-1300 K), water-to-fuel and air-to-fuel reactant feed ratios, electrochemical fuel utilization, and thermal integration of the fuel processor and the fuel cell stack subsystems. The analyses are also used to evaluate the impact of those parameters on the concentrations of methane and carbon monoxide in the processed reformate. Both of these gases can be reduced to low levels with adequate water-to-carbon used in the fuel processor. Since these two species represent corresponding amounts of hydrogen that would not be available for electrochemical oxidation in the fuel cell stack, it is important to maintain them at low levels. Subject to the assumptions used in the analyses, particularly that of thermodynamic equilibrium, it was determined that reforming temperatures of 1100 K, a water-to-carbon mole ratio of 1.5-2.5, and the use of fuel cell exhaust energy in the fuel processor subsystem can yield fuel processor efficiencies of 82-84%, and total system efficiencies of 40-42% can be achieved. For the atmospheric pressure system, if the exhaust energy is not used in the fuel processor subsystem, the fuel processor efficiency would drop to 75-82% and the total system efficiency would drop below 40%. At higher reforming temperatures, say 1300 K, the fuel processor efficiency would decrease to 78%, and the total system efficiency would drop below 39%, even with the use of the fuel cell stack exhaust energy. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Argonne Natl Lab, Argonne, IL 60439 USA. RP Doss, ED (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 10 TC 49 Z9 49 U1 1 U2 4 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0378-7753 J9 J POWER SOURCES JI J. Power Sources PD DEC 15 PY 2001 VL 102 IS 1-2 BP 1 EP 15 PG 15 WC Chemistry, Physical; Electrochemistry; Energy & Fuels; Materials Science, Multidisciplinary SC Chemistry; Electrochemistry; Energy & Fuels; Materials Science GA 499XX UT WOS:000172597000001 ER PT J AU Shim, J Lee, CR Lee, HK Lee, JS Cairns, EJ AF Shim, J Lee, CR Lee, HK Lee, JS Cairns, EJ TI Electrochemical characteristics of Pt-WO3/C and Pt-TiO2/C electrocatalysts in a polymer electrolyte fuel cell SO JOURNAL OF POWER SOURCES LA English DT Article DE polymer electrolyte fuel cell; tungsten oxide; titanium oxide; electrocatalyst ID OXYGEN REDUCTION; PLATINUM; HYDROGEN AB The electrochemical characteristics and the catalytic activity, of Pt-tungsten oxide and Pt-titanium, oxide catalysts in polymer electrolyte fuel cell were investigated by cyclic voltammetry and in fuel cells. Fuel cell performances for those catalysts at 80 degreesC with, humidified hydrogen and oxygen increased with increasing added oxide content in the catalysts up to a certain content. Adsorption characteristics for hydrogen and oxygen on the surface of platinum were greatly influenced by added oxide content in the catalysts. It was, also obtained that the electrochemically active surface area of these catalysts was influenced by their oxide content. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Lawrence Berkeley Natl Lab, Environm Energy Technol Div, Berkeley, CA 94720 USA. Woosuk Univ, Dept Chem Engn, Chunbook, South Korea. Hanyang Univ, Dept Ind Chem, Seoul 133791, South Korea. RP Shim, J (reprint author), Lawrence Berkeley Natl Lab, Environm Energy Technol Div, Berkeley, CA 94720 USA. RI Cairns, Elton/E-8873-2012 OI Cairns, Elton/0000-0002-1179-7591 NR 22 TC 240 Z9 251 U1 8 U2 89 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0378-7753 J9 J POWER SOURCES JI J. Power Sources PD DEC 15 PY 2001 VL 102 IS 1-2 BP 172 EP 177 DI 10.1016/S0378-7753(01)00817-5 PG 6 WC Chemistry, Physical; Electrochemistry; Energy & Fuels; Materials Science, Multidisciplinary SC Chemistry; Electrochemistry; Energy & Fuels; Materials Science GA 499XX UT WOS:000172597000025 ER PT J AU Simner, SP Stevenson, JW AF Simner, SP Stevenson, JW TI Compressive mica seals for SOFC applications SO JOURNAL OF POWER SOURCES LA English DT Article DE SOFC; compressive seals; leak rate ID OXIDE FUEL-CELLS; GLASS AB Muscovite and phlogopite micas have been assessed as SOFC seals at 800 degreesC. Paper gaskets, composed of pressed mica platelets in an organic binder, proved ineffective seal materials predominantly because of their uneven surface. However, cleaved natural mica sheets (with no binder) indicated far superior sealing characteristics with leak rates lower than 0.1 sccm cm(-1) at 800 degreesC, and approximately 0.7 MPa (100 psi) compressive stress. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Pacific NW Natl Lab, Mat Resource Dept, Richland, WA 99352 USA. RP Simner, SP (reprint author), Pacific NW Natl Lab, Mat Resource Dept, POB 999, Richland, WA 99352 USA. NR 10 TC 102 Z9 106 U1 2 U2 16 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0378-7753 J9 J POWER SOURCES JI J. Power Sources PD DEC 15 PY 2001 VL 102 IS 1-2 BP 310 EP 316 DI 10.1016/S0378-7753(01)00811-4 PG 7 WC Chemistry, Physical; Electrochemistry; Energy & Fuels; Materials Science, Multidisciplinary SC Chemistry; Electrochemistry; Energy & Fuels; Materials Science GA 499XX UT WOS:000172597000042 ER PT J AU Thoma, SG Trudell, DE Bonhomme, F Nenoff, TM AF Thoma, SG Trudell, DE Bonhomme, F Nenoff, TM TI Vapor phase transport synthesis of un-supported ZSM-22 catalytic membranes SO MICROPOROUS AND MESOPOROUS MATERIALS LA English DT Article DE ZSM-22; TON framework; zeolite; membrane; synthesis; 1-butene isomerization; catalysis; catalyst; vapor phase transport; catalytic membrane ID DRY GEL CONVERSION; HIGH-SILICA ZEOLITE; SKELETAL ISOMERIZATION; 1-BUTENE; THETA-1; NU-10; KZ-2 AB ZSM-22 has been synthesized from a dry amorphous gel via vapor phase transport crystallization, as bulk crystalline powder as well as an un-supported membrane. Crystalline products were characterized by powder X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy, chemical analysis, and thermal analysis. Catalytic testing was performed to demonstrate the membrane's ability to perform as an on-line catalyst. The ZSM-22 catalytic membrane showed 1-butene to isobutene conversions in excess of 60% with selectivites close to 40%, which compares well with conventionally synthesized bulk crystals. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Sandia Natl Labs, Environm Monitoring & Characterizat Dept, Albuquerque, NM 87185 USA. RP Nenoff, TM (reprint author), Sandia Natl Labs, Environm Monitoring & Characterizat Dept, POB 5800,MS 0755, Albuquerque, NM 87185 USA. NR 28 TC 27 Z9 30 U1 1 U2 21 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 15 PY 2001 VL 50 IS 1 BP 33 EP 39 DI 10.1016/S1387-1811(01)00432-2 PG 7 WC Chemistry, Applied; Chemistry, Physical; Nanoscience & Nanotechnology; Materials Science, Multidisciplinary SC Chemistry; Science & Technology - Other Topics; Materials Science GA 500CB UT WOS:000172607400004 ER PT J AU Naulleau, PP Anderson, EH Gullikson, EM Bokor, J AF Naulleau, PP Anderson, EH Gullikson, EM Bokor, J TI Fabrication of high-efficiency multilayer-coated binary blazed gratings in the EUV regime SO OPTICS COMMUNICATIONS LA English DT Article DE extreme ultraviolet; diffractive optics; blazed grating; multilayer coating; electron-beam lithography ID EXTREME-ULTRAVIOLET LITHOGRAPHY; DIFFRACTIVE OPTICAL-ELEMENTS; ELECTRON-BEAM LITHOGRAPHY; WAVELENGTH REGION; X-RAYS; PERFORMANCE; COATINGS; MO/SI AB Improving the efficiency of soft X-ray and extreme ultraviolet (EUV) gratings by way of multilayer reflection coatings has been under investigation for many years. Here we present the fabrication and characterization of binary blazed gratings designed to operate in the 14 nm wavelength region. These binary gratings are stepped approximations to the ideal sawtooth blazed-grating profile and are fabricated directly into a layer of photoresist. Norm al-incidence reflection efficiencies as high as 25% into the first-diffracted order have been demonstrated. (C) 2001 Published by Elsevier Science B.V. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Xray Opt, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept EECS, Berkeley, CA 94720 USA. RP Naulleau, PP (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Xray Opt, Berkeley, CA 94720 USA. RI Bokor, Jeffrey/A-2683-2011 NR 27 TC 19 Z9 19 U1 0 U2 3 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 2001 VL 200 IS 1-6 BP 27 EP 34 DI 10.1016/S0030-4018(01)01647-9 PG 8 WC Optics SC Optics GA 506RY UT WOS:000172986600005 ER PT J AU Demos, SG Staggs, M De Yoreo, JJ Radousky, HB AF Demos, SG Staggs, M De Yoreo, JJ Radousky, HB TI Imaging of laser-induced reactions of individual defect nanoclusters SO OPTICS LETTERS LA English DT Article ID POTASSIUM DIHYDROGEN PHOSPHATE; KH2PO4 CRYSTALS; CLUSTERS AB The response of individual defect nanoclusters located in the bulk of a dielectric material following exposure to 355-nm, 3-ns high-power laser irradiation is investigated by use of microscopic fluorescence imaging. Experiments were carried out on KH2PO4 crystals, We provide direct imaging of the reaction to an external stimulus of individual defect clusters and demonstrate a novel method of studying the dynamic behavior of bulk defects. (C) 2001 Optical Society of America. C1 Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. RP Demos, SG (reprint author), Lawrence Livermore Natl Lab, POB 808, Livermore, CA 94551 USA. NR 16 TC 15 Z9 16 U1 0 U2 2 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 2001 VL 26 IS 24 BP 1975 EP 1977 DI 10.1364/OL.26.001975 PG 3 WC Optics SC Optics GA 505XG UT WOS:000172940400012 PM 18059750 ER PT J AU Trinkle, JC Tzitzouris, JA Pang, JS AF Trinkle, JC Tzitzouris, JA Pang, JS TI Dynamic multi-rigid-body systems with concurrent distributed contacts SO PHILOSOPHICAL TRANSACTIONS OF THE ROYAL SOCIETY A-MATHEMATICAL PHYSICAL AND ENGINEERING SCIENCES LA English DT Article DE multi-rigid-body contact problem; torsional friction; maximum work inequality; complementarity; time-stepping methods ID COULOMB-FRICTION AB Consider a system of rigid bodies with multiple concurrent contacts. The multi-rigid-body contact problem is to predict the accelerations of the bodies and the normal and friction loads acting at the contacts. This paper presents theoretical results for the multi-rigid-body contact problem under the assumptions that one or more contacts occur over locally planar, finite regions and that friction forces are consistent with the maximum work inequality. Existence and uniqueness results are presented for this problem under mild assumptions on the system inputs. In addition, the performance of two different time-stepping methods for integrating the dynamics are compared on two simple problems. C1 Sandia Natl Labs, Intelligent Syst Principles Dept, Albuquerque, NM 87185 USA. Johns Hopkins Univ, Dept Math Sci, Baltimore, MD 21218 USA. RP Sandia Natl Labs, Intelligent Syst Principles Dept, POB 5800, Albuquerque, NM 87185 USA. EM jctrink@sandia.gov; jimt2@mts.jhu.edu; jsp@vicpl.mts.jhu.edu NR 17 TC 32 Z9 32 U1 3 U2 6 PU ROYAL SOC PI LONDON PA 6-9 CARLTON HOUSE TERRACE, LONDON SW1Y 5AG, ENGLAND SN 1364-503X EI 1471-2962 J9 PHILOS T R SOC A JI Philos. Trans. R. Soc. A-Math. Phys. Eng. Sci. PD DEC 15 PY 2001 VL 359 IS 1789 BP 2575 EP 2593 PG 19 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 504MJ UT WOS:000172860200016 ER PT J AU Bringa, EM Nordlund, K Keinonen, J AF Bringa, EM Nordlund, K Keinonen, J TI Cratering-energy regimes: From linear collision cascades to heat spikes to macroscopic impacts SO PHYSICAL REVIEW B LA English DT Article ID MOLECULAR-DYNAMICS SIMULATION; ION-BEAM MODIFICATION; EMBEDDED-ATOM-METHOD; CYLINDRICAL TRACK; FORCE-MICROSCOPY; CLUSTER-IMPACT; SURFACE DAMAGE; SOLID-SURFACES; GOLD CLUSTERS; FCC METALS AB Using classical molecular-dynamics simulations we examine the formation of craters during 0.4-100-keV Xe bombardment of Au. Our simulation results, and comparison with experiments and simulations of other groups, are used to examine to what extent analytical models can be used to predict the size and properties of craters. We do not obtain a fully predictive analytical model (with no fitting parameters) for the cratering probability, because of the difficulty in predicting the probability of cascades splitting into subcascades, and the relation of the heat spike lifetime and energy density. We do, however, demonstrate that the dependence of the crater size on the incident ion energy can be well understood qualitatively in terms of the lifetime of the heat spike and the cohesive energy of the material. We also show that a simple energy density criterion cannot be used to predict cratering in a wide ion energy range because of the important role of the heat spike lifetime in high-energy cascades. The cohesive energy dependence differs from that obtained for macroscopic cratering (observed, e.g., in astrophysics) because of the crucial role of melting in the development of heat spikes. C1 Univ Virginia, Engn Phys & Astron Dept, Charlottesville, VA 22903 USA. Univ Helsinki, Accelerator Lab, FIN-00014 Helsinki, Finland. RP Lawrence Livermore Natl Lab, POB 808,L-353, Livermore, CA 94550 USA. EM bringa1@llnl.gov RI Bringa, Eduardo/F-8918-2011; Keinonen, Juhani/D-4347-2013; Nordlund, Kai/L-8275-2014 OI Nordlund, Kai/0000-0001-6244-1942 NR 56 TC 56 Z9 56 U1 0 U2 9 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 2001 VL 64 IS 23 AR 235426 DI 10.1103/PhysRevB.64.235426 PG 12 WC Physics, Condensed Matter SC Physics GA 504QT UT WOS:000172867900142 ER PT J AU Cuenya, BR Keune, W Sturhahn, W Toellner, TS Hu, MY AF Cuenya, BR Keune, W Sturhahn, W Toellner, TS Hu, MY TI Structure and vibrational dynamics of interfacial Sn layers in Sn/Si multilayers SO PHYSICAL REVIEW B LA English DT Article ID NUCLEAR RESONANT SCATTERING; DENSITY-OF-STATES; RAMAN-SCATTERING; ALPHA-SN; SYNCHROTRON-RADIATION; AMORPHOUS-SILICON; BEAM EPITAXY; THIN-FILMS; GE; GROWTH AB The structure and vibrational dynamics of room-temperature-grown nanoscale Sn/amorphous (a-)Si multilayers have been studied by x-ray diffraction, Raman scattering, Sn-119 Mossbauer spectroscopy, and Sn-119 nuclear-resonant inelastic x-ray scattering (NRIXS) of synchrotron radiation. With increasing Sn-layer thickness, the formation of beta -Sn was observed, except at the Sn/Si interfaces, where a 10-Angstrom -thick metastable pure amorphous-alpha -Sn-like layer remains stabilized. By means of NRIXS we have measured the Sn-projected vibrational density of states (VDOS) in these multilayers (in particular, at the interfaces), and in 500-Angstrom -thick epitaxial alpha -Sn films on InSb(001) as a reference. Further, the Sn-specific Lamb-Mossbauer factor (f factor), mean kinetic energy per atom, mean atomic force constant, and vibrational entropy per atom were obtained. The VDOS of the amorphous-alpha -Sn-like interface layer is observed to be distinctly different from that of (bulk) alpha -Sn and beta -Sn, and its prominent vibrational energies are found to scale with those of amorphous Ge and Si. The observed small difference in vibrational entropy (DeltaS/k(B) = +0.17 +/-0.05 per atom) between alpha -Sn and interfacial amorphous-alpha -like Sn does not account for the stability of the latter phase. C1 Gerhard Mercator Univ, Lab Angew Phys, D-47048 Duisburg, Germany. Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. RP Gerhard Mercator Univ, Lab Angew Phys, D-47048 Duisburg, Germany. EM roldan@uni-duisburg.de RI Roldan Cuenya, Beatriz/L-1874-2016 OI Roldan Cuenya, Beatriz/0000-0002-8025-307X NR 51 TC 18 Z9 18 U1 1 U2 12 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 2001 VL 64 IS 23 AR 235321 DI 10.1103/PhysRevB.64.235321 PG 12 WC Physics, Condensed Matter SC Physics GA 504QT UT WOS:000172867900105 ER PT J AU Gao, F Bylaska, EJ Weber, WJ Corrales, LR AF Gao, F Bylaska, EJ Weber, WJ Corrales, LR TI Ab initio and empirical-potential studies of defect properties in 3C-SiC SO PHYSICAL REVIEW B LA English DT Article ID THRESHOLD DISPLACEMENT ENERGIES; SILICON-CARBIDE; ELECTRONIC-STRUCTURE; CARBON RINGS; PSEUDOPOTENTIALS; SIMULATIONS; CASCADES; METALS; STATE AB Density functional theory (DFT) is used to study the formation and properties of native defects in 3 C-SiC. Extensive calculations have been carried out to determine the formation of point defects and the stability of self-interstitials. Although there is good agreement in the formation of vacancies and antisitc defects between the present study and previous calculations. a large disparity appears in the formation of self-interstitials, The most favorable configurations for C interstitials are [100] and [110] dumbbells. with formation energies front 3.16 to 3.59 eV, and the most favorable Si interstitial is Si tetrahedral surrounded by four C atoms. with a formation energy of 6.17 eV. The present DFT results are also compared with those Calculated by molecular dynamics (MD) simulations using the Tersoff potentials, with parameters obtained from the literature. The formation energies of vacancies and antisite defects obtained by MD calculation are in good agreement with those obtained by DFT calculations. However, the MD Calculations yield different results for interstitials energies and structures that depend on the cutoff distances used in the Tersoff potentials. The results provide guidelines for evaluating the quality and fit of empirical potentials for large-scale Simulations of irradiation damage and defect migration processes in SiC. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Gao, F (reprint author), Pacific NW Natl Lab, POB 999, Richland, WA 99352 USA. EM fei.gao@pnl.gov RI Weber, William/A-4177-2008; Gao, Fei/H-3045-2012 OI Weber, William/0000-0002-9017-7365; NR 35 TC 78 Z9 78 U1 10 U2 52 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 2001 VL 64 IS 24 AR 245208 DI 10.1103/PhysRevB.64.245208 PG 7 WC Physics, Condensed Matter SC Physics GA 508HK UT WOS:000173082500046 ER PT J AU Guo, CL Taylor, AJ AF Guo, CL Taylor, AJ TI Nonlinear optical study of the Fermi-surface oscillation in gold induced by acoustic-phonon excitation SO PHYSICAL REVIEW B LA English DT Article ID PHASE-TRANSITION; ELECTRON; COPPER; GENERATION; EXPANSION; METALS; PULSES AB Using a two-color ultrafast optical pump-probe technique with an amplified Ti:sapphire femtosecond laser system, we study the heat-induced structural dynamics in gold by monitoring both the fundamental and third harmonic generation (THG) signals of the probe beam. An amplitude oscillation, with a period of tens of picoseconds, is clearly observed in the THG signal, but absent in fundamental, In contrast to previous understandings from a purely mechanical deformation point of view, we demonstrate that this oscillation in THG directly results from a periodic modulation of the Fermi level in gold driven by acoustic-phonon excitation following ultrafast laser heating. C1 Los Alamos Natl Lab, Condensed Matter & Thermal Phys Grp, Los Alamos, NM 87545 USA. RP Guo, CL (reprint author), Univ Rochester, Inst Opt, Rochester, NY 14627 USA. NR 20 TC 4 Z9 4 U1 1 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 2001 VL 64 IS 24 AR 245106 DI 10.1103/PhysRevB.64.245106 PG 4 WC Physics, Condensed Matter SC Physics GA 508HK UT WOS:000173082500025 ER PT J AU Harrison, WA AF Harrison, WA TI Theory of the electronic structure of the alloys of the actinides SO PHYSICAL REVIEW B LA English DT Article AB An earlier theory of the electronic structure of the actinides is improved, generalized to alloys of actinides, and applied to plutonium and its alloys with other trivalent metals. The theory combines the s and d electrons as free electrons, treating them to second order in an empty-core pseudopotential. The f levels produce bands in this theory. which are actually broadened by electron correlations, but their role in the bonding is decreased. The effects both of the coupling between neighboring f shells and of the correlation are included in a second moment in terms of which the total energy is estimated using a Friedel model. This allows all contributions to be rewritten in terms of near-neighbor interactions and on-site terms. It is found that f-shell contribution alone favors a much smaller spacing than the free-electron contribution alone. and the competition makes the resulting structure very sensitive to the parameters of the theory. Adjustment of the parameters seems essential. An f-shell radius is adjusted, within the range of previous estimates, so that the minimum in the f-shell contributions for plutonium comes at a spacing of 2.5 A, and the total is scaled back such that the minimum is of the same depth. The same scaling factors are applied to other actinides. Then the pseudopotential core radius is adjusted for each actinide and trivalent simple metal in the face-centered-cubic structure to yield the observed atomic volume (that for the delta structure in the case of plutonium). The resulting electronic structure is tested successfully by using it to predict the bulk modulus of all of these metals. Using the same parameters for plutonium, the energy is calculated in the alpha structure, found to haec higher energy than the fee structure at the atomic volume of delta plutonium, but lower energy at a reduced volume, near that of the observed low-temperature a structure. The same formulas and parameters are applicable to random alloys of any of these metals, evaluating each term in an alloy of x atomic fraction of B in A with the appropriate weighting of x, x(1-x), or (1-x)(2). This does not predict correct variations with concentration x of the lattice pacings unless we introduce the interaction between simple-metal core d states and actinide valence d states, absent in the pure materials. A moderate scaling of previously predicted d-state radii brings the dilute-alloy spacings into accord with experiment for plutonium alloys with gallium, indium, and thallium. Aluminum. without core d states, was initially in accord and is not affected. The ordered alloys, Pu3Ga, Pu3In, and Pu3Al, are found to have larger spacings than the random alloys. in accord with experiment, though Pu3Al is not found to be the stable structure. For alloys of two actinides, or with rare earths, the effects of d-state couplings are expected to be negligible, but additional terms in the f-state energy arise from the contribution of f levels of different energy to the global f bands. With this effect included, cerium. americium, and curium are found to increase the spacing of delta plutonium. in accord with experiment. but the lighter actinides, as well as the type-B simple metals. Al, Ga, In. and Tl decrease the spacing, also in accord with experiment. Alloys with the type A metals Sc, Y, and La are found to increase the spacing. Initial studies of the displacement of plutonium neighbors to substituted gallium atoms showed alpha -like reconstructions, as in pure plutonium. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Stanford Univ, Dept Appl Phys, Stanford, CA 94305 USA. RP Los Alamos Natl Lab, T1,MS B221, Los Alamos, NM 87545 USA. NR 16 TC 12 Z9 12 U1 2 U2 6 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 2001 VL 64 IS 23 AR 235112 DI 10.1103/PhysRevB.64.235112 PG 10 WC Physics, Condensed Matter SC Physics GA 504QT UT WOS:000172867900056 ER PT J AU Jaffe, JE Zunger, A AF Jaffe, JE Zunger, A TI Defect-induced nonpolar-to-polar transition at the surface of chalcopyrite semiconductors SO PHYSICAL REVIEW B LA English DT Article ID MOLECULAR-DYNAMICS; TOTAL-ENERGY; CUINSE2; METALS; FORMALISM; CLEAVAGE AB In zinc-blende semiconductors, the nonpolar (110) surface is more stable than all polar surfaces because the formation of the latter requires the creation of charge-neutralizing but energetically costly surface reconstruction. Our first-principles calculations on CuInSe2 reveal this in the double-zinc-blende (chalcopyrite) structure, the defect-induced reconstructions make the (112)-cation plus ((1) over bar(1) over bar(2) over bar)-anion polar facets lower in energy than the nonpolar (110) plane, despite the resulting increased surface area. We show that this spontaneous facetting results from the remarkable stability of surface defects (Cu vacancy, Cu-on-In antisite) in chalcopyrites, and explains the hitherto puzzling formation of polar microfacets when one attempts to grow epitaxialloy a nonpolar chalcopyrite surface. C1 Pacific NW Natl Lab, William R Wiley Environm Mol Sci Lab, Richland, WA 99352 USA. Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Jaffe, JE (reprint author), Pacific NW Natl Lab, William R Wiley Environm Mol Sci Lab, Richland, WA 99352 USA. RI Zunger, Alex/A-6733-2013 NR 28 TC 77 Z9 77 U1 0 U2 16 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 2001 VL 64 IS 24 AR 241304 DI 10.1103/PhysRevB.64.241304 PG 4 WC Physics, Condensed Matter SC Physics GA 508HK UT WOS:000173082500009 ER PT J AU Kramper, P Birner, A Agio, M Soukoulis, CM Muller, F Gosele, U Mlynek, J Sandoghdar, V AF Kramper, P Birner, A Agio, M Soukoulis, CM Muller, F Gosele, U Mlynek, J Sandoghdar, V TI Direct spectroscopy of a deep two-dimensional photonic crystal microresonator SO PHYSICAL REVIEW B LA English DT Article ID NEAR-INFRARED WAVELENGTHS; MACROPOROUS SILICON; COUPLING EFFICIENCY; WAVE-GUIDES; MICROCAVITIES; INGAASP AB Photonic crystals based on macroporous silicon with fundamental band gaps in the middle infrared region 3.4-5.8 mum were fabricated. Scanning probe optical microscopy and laser spectroscopy were combined to examine a deep two-dimensional photonic crystal microresonator based on a single point defect. Two sharp resonances were recorded in the band gap, in excellent agreement with the results of numerical simulations. Such a microresonator with high-quality factors and a subwavelength mode extension could be used for a range of applications including integrated optical gas sensors. C1 Univ Konstanz, Fachbereich Phys, D-78457 Constance, Germany. Max Planck Inst Mikrostrukturphys, D-06120 Halle An Der Saale, Germany. Univ Pavia, Dipartimento Fis A Volta, INFM, I-27100 Pavia, Italy. Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Res Ctr Crete, Iraklion, Crete, Greece. RP Swiss Fed Inst Technol, Phys Chem Lab, CH-8093 Zurich, Switzerland. EM vahid.sandoghdar@ethz.ch RI Agio, Mario/F-7366-2011; Sandoghdar, Vahid/C-7390-2013; Soukoulis, Costas/A-5295-2008 OI Agio, Mario/0000-0003-3282-5982; NR 31 TC 30 Z9 31 U1 0 U2 6 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 2001 VL 64 IS 23 AR 233102 DI 10.1103/PhysRevB.64.233102 PG 4 WC Physics, Condensed Matter SC Physics GA 504QT UT WOS:000172867900002 ER PT J AU Levin, EM Pecharsky, VK Gschneidner, KA Miller, GJ AF Levin, EM Pecharsky, VK Gschneidner, KA Miller, GJ TI Electrical resistivity, electronic heat capacity, and electronic structure of Gd5Ge4 SO PHYSICAL REVIEW B LA English DT Article ID PHASE-TRANSITION; MAGNETIC-FIELD; MAGNETORESISTANCE; GD-5(SI2GE2); RESISTANCE; GD-5(SI1.8GE2.2); FERROMAGNETS; TEMPERATURE; MANGANITES; ANOMALIES AB Temperature and do magnetic-field dependencies of the electrical resistivity (4.3-300 K, 0-40 kOe) and heat capacity (3.5-14 K- 0-100 kOe) of polycrystalline Gd5Ge4 have been measured. The electrical resistivity of Gd5Ge4 shows a transition between the low-temperature metallic and high-temperature insulatorlike states at similar to 130 K. In the low-temperature metallic state both the resistivity and electronic heat capacity of Gd5Ge4 indicate a possible presence of a narrow conduction band. Both low- and high-temperature behaviors of the electrical resistivity of Gd5Ge4 correlate with the crystallographic and magnetic phase transitions induced by temperature and/or magnetic field. Several models, which can describe the unusual behavior of the electrical resistance of Gd5Ge4 above 130 K, are discussed. Preliminary tight-binding linear muffin-tin orbital calculations show that Gd5Ge4 behaves as a metal in the low-temperature magnetically ordered state, and as a Mott-Hubbard "semiconductor" in the high-temperature magnetically disordered state. C1 Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Mat Sci & Engn, Ames, IA 50011 USA. Iowa State Univ, Dept Chem, Ames, IA 50011 USA. RP Iowa State Univ, Ames Lab, 242 Spedding, Ames, IA 50011 USA. NR 42 TC 82 Z9 85 U1 1 U2 11 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 2001 VL 64 IS 23 AR 235103 DI 10.1103/PhysRevB.64.235103 PG 11 WC Physics, Condensed Matter SC Physics GA 504QT UT WOS:000172867900047 ER PT J AU Melechko, AV Simkin, MV Samatova, NF Braun, J Plummer, EW AF Melechko, AV Simkin, MV Samatova, NF Braun, J Plummer, EW TI Complex structural phase transition in a defect-populated two-dimensional system SO PHYSICAL REVIEW B LA English DT Article ID CHARGE-DENSITY-WAVE; SURFACE PHASE; BAND-STRUCTURE; SN/GE(111); PB/GE(111); SEMICONDUCTORS; DRIVEN; STM AB A complex phase transition in Sri/Ge(111) and similar systems can be decomposed into two intertwined phase transitions: a structural symmetry lowering (root3 x root3) double left right arrow (3x3) transition and a disorder-order transition in the defect distribution, We present two phenomenological models that describe these transitions and their interrelation. These models allow us to understand the formation of domains and domain walls at low temperatures, defect-induced density waves above the structural transition temperature, and ordering of the defects caused by lattice-mediated defect-defect interactions. The models predict a destruction of the pure structural transition when impurities are introduced into the system, a shift in the structural crossover temperature with impurity density. and a dependence of the (3x3) lattice structure on the specific defect alignment. C1 Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Oak Ridge Natl Lab, Div Math & Comp Sci, Oak Ridge, TN 37831 USA. RP Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. RI Melechko, Anatoli/B-8820-2008 NR 38 TC 12 Z9 12 U1 0 U2 1 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 2001 VL 64 IS 23 AR 235424 DI 10.1103/PhysRevB.64.235424 PG 12 WC Physics, Condensed Matter SC Physics GA 504QT UT WOS:000172867900140 ER PT J AU Meng, S Schroeder, BR Bostwick, A Olmstead, MA Rotenberg, E Ohuchi, FS AF Meng, S Schroeder, BR Bostwick, A Olmstead, MA Rotenberg, E Ohuchi, FS TI Low-energy photoelectron diffraction structure determination of GaSe-bilayer-passivated Si(111) SO PHYSICAL REVIEW B LA English DT Article ID ABSORPTION FINE-STRUCTURE; ATOMIC-STRUCTURE; SURFACE; GROWTH; HETEROEPITAXY; SILICON; EPITAXY; FILMS AB The atomic structure of GaSe-bilayer-passivated Si(111) was determined using low-energy photoelectron diffraction (PED). Scanned-energy and scanned-angle PED measurements were combined with multiple-scattering calculations to investigate the specific bonding configuration and to test the applicability of these techniques in an electron energy range where multiple and back scattering are important. Using tunable synchrotron radiation to vary the electron wavelength for emission along the Ga-Si and Ga-Se bonds, we determined the Ga site to be directly atop a surface Si atom with a bond length of 2.35 +/- 0.02 Angstrom. We find the Ga-Se bond lies 65 degrees from the surface normal towards [11 (2) over bar], with length 2.44 +/- 0.01 Angstrom. Diffraction stereograms [variable-angle scattering at constant kinetic energy (KE)] for Ga 3d emission (KE=230 eV) show threefold symmetric, forward-focusing peaks along Ga-Se bonds, indicating a single-domained bilayer. Se 3d stereograms (KE=196 eV) show a sixfold ripple pattern due to scattering from the six in-plane Se next-nearest neighbors. Multiple scattering analysis is required to explain the full diffraction pattern for this two-layer thick film. Polar-angle scans at constant azimuth and kinetic energy were measured using conventional laboratory x-ray sources for Ga 2p (KE = 131 eV) and Se 2p (KE = 48 eV). The results, subjected to multiple-scattering analysis, are consistent with the structure determined using synchrotron radiation. These results demonstrate low-energy PED as an effective tool in structural determination. C1 Univ Washington, Dept Phys, Seattle, WA 98195 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Adv LIght Source, Berkeley, CA 94720 USA. Univ Washington, Dept Mat Sci & Engn, Seattle, WA 98195 USA. RP Univ Washington, Dept Phys, Box 351560, Seattle, WA 98195 USA. RI Rotenberg, Eli/B-3700-2009; Bostwick, Aaron/E-8549-2010 OI Rotenberg, Eli/0000-0002-3979-8844; NR 29 TC 11 Z9 11 U1 1 U2 4 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 2001 VL 64 IS 23 AR 235314 DI 10.1103/PhysRevB.64.235314 PG 8 WC Physics, Condensed Matter SC Physics GA 504QT UT WOS:000172867900098 ER PT J AU Mryasov, ON Freeman, AJ AF Mryasov, ON Freeman, AJ TI Electronic band structure of indium tin oxide and criteria for transparent conducting behavior SO PHYSICAL REVIEW B LA English DT Article ID SN-DOPED IN2O3; OPTICAL-PROPERTIES; FILMS AB Indium-based transparent conductors, notably indium tin oxide (ITO), have a wide range of applications due to a unique combination of visible light transparency and modest conductivity. A fundamental understanding of such an unusual combination of properties is strongly motivated by the great demand for materials with improved transparent conducting properties. Here we formulate conditions for transparent conducting behavior on the basis of the local density full-potential linear muffin-tin orbital electronic band structure calculations for Sn-doped In2O3 and available experimental data. We conclude that the position, dispersion, and character of the lowest conduction band are the key characteristics of the band structure responsible for its electro-optical properties. Further, we find that this lowest band is split with Sri doping due to the strong hybridization with dopant s-type states and this splitting contributes to both the decrease of the plasma frequency and the mobility of the carriers. C1 Northwestern Univ, Mat Res Ctr, Evanston, IL 60208 USA. Northwestern Univ, Dept Phys & Astron, Evanston, IL 60208 USA. RP Sandia Natl Labs, Mail Stop 9161,POB 0969, Livermore, CA 94551 USA. EM onm@pluto.phys.nwu.edu NR 12 TC 163 Z9 166 U1 5 U2 67 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 2001 VL 64 IS 23 AR 233111 DI 10.1103/PhysRevB.64.233111 PG 3 WC Physics, Condensed Matter SC Physics GA 504QT UT WOS:000172867900011 ER PT J AU Nardelli, MB Fattebert, JL Bernholc, J AF Nardelli, MB Fattebert, JL Bernholc, J TI O(N) real-space method for ab initio quantum transport calculations: Application to carbon nanotube-metal contacts SO PHYSICAL REVIEW B LA English DT Article ID FIRST-PRINCIPLES CALCULATION; QUANTIZED CONDUCTANCE; ELECTRONIC-STRUCTURE; ATOMIC WIRES; SINGLE; RESISTANCE; NANOCONTACTS; INTERFACES; FORMULA; DEFECTS AB \We present an ab initio O(N) method that combines an accurate optimized-orbital solution of the electronic structure problem with an efficient Green's function technique for evaluating the quantum conductance, As an important illustrative example, we investigate carbon nanotube-metal contacts and explain the anomalously large contact resistance observed in nanotube devices as due to the spatial separation of their conductance eigenchannels. The results for various contact geometries and strategies for improving device performance are discussed. C1 N Carolina State Univ, Dept Phys, Raleigh, NC 27695 USA. Lawrence Livermore Natl Lab, Ctr Appl Sci Comp, Livermore, CA 94551 USA. RP N Carolina State Univ, Dept Phys, Raleigh, NC 27695 USA. RI Buongiorno Nardelli, Marco/C-9089-2009 NR 45 TC 91 Z9 91 U1 0 U2 8 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 2001 VL 64 IS 24 AR 245423 DI 10.1103/PhysRevB.64.245423 PG 5 WC Physics, Condensed Matter SC Physics GA 508HK UT WOS:000173082500117 ER PT J AU Riva, C Peeters, FM Varga, K AF Riva, C Peeters, FM Varga, K TI Positively charged magnetoexcitons in a semiconductor quantum well SO PHYSICAL REVIEW B LA English DT Article ID HIGH MAGNETIC-FIELDS; ENERGY-LEVELS; EXCITONS; PHOTOLUMINESCENCE; TRANSLATIONS; STATE; HOLES AB A variational calculation of the lower singlet and triplet states of positively charged excitons (trions), confined to a single quantum well and in the presence of a perpendicular magnetic field, is presented. All the three particles of the exciton complex are treated within the effective-mass approximation. We study the dependence of the energy levels and of the binding energy on the well width and on the magnetic-field strength. Our results are compared with the available experimental data, and show a good qualitative and quantitative agreement. A ringlet-triplet crossing is found which for a 200-Angstrom -wide GaAs is predicted to occur for B = 15 T. C1 Univ Instelling Antwerp, Dept Nat Kunde, B-2610 Antwerp, Belgium. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Univ Instelling Antwerp, Dept Nat Kunde, B-2610 Antwerp, Belgium. EM riva@uia.ua.ac.be; peeters@uia.ua.ac.be RI Varga, Kalman/A-7102-2013; CMT, UAntwerpen Group/A-5523-2016 NR 29 TC 23 Z9 23 U1 0 U2 0 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 2001 VL 64 IS 23 AR 235301 DI 10.1103/PhysRevB.64.235301 PG 5 WC Physics, Condensed Matter SC Physics GA 504QT UT WOS:000172867900085 ER PT J AU Vaschenko, G Patel, D Menoni, CS Gardner, NF Sun, J Gotz, W Tome, CN Clausen, B AF Vaschenko, G Patel, D Menoni, CS Gardner, NF Sun, J Gotz, W Tome, CN Clausen, B TI Significant strain dependence of piezoelectric constants in InxGa1-x/GaN quantum wells SO PHYSICAL REVIEW B LA English DT Article ID ELECTRIC-FIELD; GAN; PRESSURE; POLARIZATION; ALN; NITRIDE AB Using hydrostatic pressure to modify the strain in InxGa1-xN/GaN quantum wells we show an almost twofold increase of the built-in piezoelectric field in the wells from 1.4 MV/cm at atmospheric pressure to 2.6 MV/cm at 8.7 GPa. An analysis in terms of the total strain generated by the pressure suggests that the increase in the field arises from a significant dependence of the piezoelectric constants on strain. C1 Colorado State Univ, Dept Elect & Comp Engn, Ft Collins, CO 80523 USA. LumiLeds Lighting, San Jose, CA 95131 USA. Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. RP Vaschenko, G (reprint author), Colorado State Univ, Dept Elect & Comp Engn, Ft Collins, CO 80523 USA. RI Menoni, Carmen/A-3775-2008; Menoni, Carmen/B-4989-2011; Tome, Carlos/D-5058-2013; Clausen, Bjorn/B-3618-2015 OI Clausen, Bjorn/0000-0003-3906-846X NR 18 TC 45 Z9 53 U1 2 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 2001 VL 64 IS 24 AR 241308 DI 10.1103/PhysRevB.64.241308 PG 4 WC Physics, Condensed Matter SC Physics GA 508HK UT WOS:000173082500013 ER PT J AU Zhang, PH Crespi, VH Chang, E Louie, SG Cohen, ML AF Zhang, PH Crespi, VH Chang, E Louie, SG Cohen, ML TI Theory of metastable group-IV alloys formed from CVD precursors SO PHYSICAL REVIEW B LA English DT Article ID TEMPERATURE EPITAXIAL-GROWTH; SI-C ALLOYS; OPTICAL-PROPERTIES; ELECTRONIC-PROPERTIES; POROUS SILICON; LASER-ABLATION; QUANTUM WIRES; TOTAL-ENERGY; PSEUDOPOTENTIALS; SUPERLATTICES AB Using chemical-vapor deposition (CVD) precursors, group-IV compounds such as Si4C and Ge4C, which incorporate 20 at. % carbon, have been synthesized. Here we present systematic ab initio studies of the electronic and structural properties of group-IV compounds formed from CVD precursors. We also propose a class of precursor molecules for materials containing 25 at. % carbon. These compounds are energetically comparable to already synthesized materials (e.g., Ge4C) and are semimetallic within the local-density approximation. In addition, we give information for two previously proposed group-IV compounds, Si2Sn2C and Ge3SnC, which are direct-gap semiconductors and match the lattice of silicon to within 1%. C1 Penn State Univ, Dept Phys, Davey Lab 104, University Pk, PA 16802 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Penn State Univ, Dept Phys, Davey Lab 104, University Pk, PA 16802 USA. RI Zhang, Peihong/D-2787-2012 NR 40 TC 10 Z9 10 U1 0 U2 1 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 2001 VL 64 IS 23 AR 235201 DI 10.1103/PhysRevB.64.235201 PG 10 WC Physics, Condensed Matter SC Physics GA 504QT UT WOS:000172867900074 ER PT J AU Blagoev, KB Cooper, F Dawson, JF Mihaila, B AF Blagoev, KB Cooper, F Dawson, JF Mihaila, B TI Schwinger-Dyson approach to nonequilibrium classical field theory SO PHYSICAL REVIEW D LA English DT Article ID LARGE-N EXPANSION; SCALAR FIELD; TIME EVOLUTION; QUANTUM EVOLUTION; DYNAMICS; APPROXIMATION; THERMALIZATION; FORMULATION; RELAXATION; MECHANICS AB In this paper we discuss a Schwinger-Dyson (SD) approach for determining the time evolution of the unequal time correlation functions of a nonequilibrium classical field theory, where the classical system is described by an initial density matrix at time t=0. We focus on lambda phi (4) field theory in 1 + 1 space-time dimensions where we can perform exact numerical simulations by sampling an ensemble of initial conditions specified by the initial density matrix. We discuss two approaches. The first, the bare vertex approximation (BVA), is based on ignoring vertex corrections to the SD equations in the auxiliary field formalism relevant for 1/N expansions. The second approximation is a related approximation made to the SD equations of the original formulation in terms of phi alone. We compare these SD approximations as well as a Hartree approximation with exact numerical simulations. We find that both approximations based on the SD equations yield good agreement with exact numerical simulations and cure the late time oscillation problem of the Hartree approximation. We also discuss the relationship between the quantum and classical SD equations. C1 Boston Coll, Dept Phys, Chestnut Hill, MA 02167 USA. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Univ New Hampshire, Dept Phys, Durham, NH 03824 USA. Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. RP Blagoev, KB (reprint author), Boston Coll, Dept Phys, Chestnut Hill, MA 02167 USA. RI Mihaila, Bogdan/D-8795-2013 OI Mihaila, Bogdan/0000-0002-1489-8814 NR 65 TC 37 Z9 37 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 2001 VL 64 IS 12 AR 125003 DI 10.1103/PhysRevD.64.125003 PG 16 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 504QJ UT WOS:000172867100067 ER PT J AU Cornwall, JM Grigoriev, D Kusenko, A AF Cornwall, JM Grigoriev, D Kusenko, A TI Resonant amplification of electroweak baryogenesis at preheating SO PHYSICAL REVIEW D LA English DT Article ID NUMBER NON-CONSERVATION; FINITE TEMPERATURES; PHASE-TRANSITIONS; MAGNETIC-FIELDS; ADIABATIC LIMIT; EARLY UNIVERSE; GAUGE-THEORIES; PAIR CREATION; INFLATION; NONCONSERVATION AB We explore viable scenarios for parametric resonant amplification of electroweak (EW) gauge fields and the Chern-Simons number during preheating, leading to baryogenesis at the EW scale. In this class of scenarios time-dependent classical EW gauge fields, essentially spatially homogeneous on the horizon scales, carry the Chem-Simons number which can be amplified by parametric resonance up to magnitudes at which unsuppressed topological transitions in the Higgs sector become possible. Baryon number nonconservation associated with the gauge sector and the highly non-equilibrium nature of preheating allow for efficient baryogenesis. The requisite large CP violation can arise either from the time dependence of a slowly varying Higgs field (spontaneous baryogenesis) or from a resonant amplification of CP violation induced in the gauge sector through loops. We identify several CP-violating operators, in the standard model and its minimal extensions that can facilitate efficient baryogenesis at preheating, and we show how to overcome would-be exponential suppression of baryogenesis associated with tunneling barriers. C1 Univ Calif Los Angeles, Dept Phys & Astron, Los Angeles, CA 90095 USA. Brookhaven Natl Lab, RIKEN, Res Ctr, Upton, NY 11973 USA. RP Univ Calif Los Angeles, Dept Phys & Astron, Los Angeles, CA 90095 USA. NR 49 TC 11 Z9 11 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0010 EI 2470-0029 J9 PHYS REV D JI Phys. Rev. D PD DEC 15 PY 2001 VL 64 IS 12 AR 123518 DI 10.1103/PhysRevD.64.123518 PG 20 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 504QJ UT WOS:000172867100028 ER PT J AU Dimopoulos, S Kachru, S Kaloper, N Lawrence, A Silverstein, E AF Dimopoulos, S Kachru, S Kaloper, N Lawrence, A Silverstein, E TI Small numbers from tunneling between brane throats SO PHYSICAL REVIEW D LA English DT Article ID HETEROTIC STRING THEORY; SUPERSYMMETRY BREAKING; EXTRA DIMENSIONS; COSMOLOGICAL CONSTANT; GAUGINO MEDIATION; HIERARCHY PROBLEM; DOMAIN-WALLS; 5D GRAVITY; SUPERGRAVITY; SCALE AB Genetic classes of string compactifications include "brane throats" emanating from the compact dimensions and separated by effective potential barriers raised by the background gravitational fields. The interaction of observers inside different throats occurs via tunneling and is consequently weak. This provides a new mechanism for generating small numbers in nature. We apply it to the hierarchy problem, where supersymmetry breaking near the unification scale causes TeV sparticle masses inside the standard model throat. We also design naturally long-lived cold dark matter which decays within a Hubble time to the approximate conformal matter of a long throat, This may soften structure formation at galactic scales and raises the possibility that much of the dark matter of the universe is conformal matter. Finally, the tunneling rate shows that the coupling between throats, mediated by bulk modes, is stronger than a naive application of holography suggests. C1 Stanford Univ, Dept Phys, Stanford, CA 94305 USA. Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94305 USA. Univ Calif Santa Barbara, Inst Theoret Phys, Santa Barbara, CA 93106 USA. Duke Univ, Ctr Geometry & Theoret Phys, Durham, NC 27708 USA. RP Stanford Univ, Dept Phys, Stanford, CA 94305 USA. OI Lawrence, Albion/0000-0003-4116-045X NR 68 TC 57 Z9 57 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0010 EI 2470-0029 J9 PHYS REV D JI Phys. Rev. D PD DEC 15 PY 2001 VL 64 IS 12 AR 121702 DI 10.1103/PhysRevD.64.121702 PG 5 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 504QJ UT WOS:000172867100003 ER PT J AU Huterer, D Turner, MS AF Huterer, D Turner, MS TI Probing dark energy: Methods and strategies SO PHYSICAL REVIEW D LA English DT Article ID MICROWAVE BACKGROUND ANISOTROPIES; SMALL COSMOLOGICAL CONSTANT; STRING-DOMINATED UNIVERSE; LY-ALPHA FOREST; COSMIC EQUATION; REDSHIFT SURVEYS; IA SUPERNOVAE; STATE; QUINTESSENCE; CLUSTERS AB The presence of dark energy in the Universe is infer-red directly from the accelerated expansion of the Universe, and, indirectly, from measurements of cosmic microwave background (CMB) anisotropy. Dark energy contributes about two-thirds of the critical density, is smoothly distributed, has large negative pressure, and is very mysterious. For now, all of its discernible cosmological consequences follow from its effect on the expansion rate of the Universe. Absent a compelling theoretical model (or even a class of models), we describe the dark energy by its equation of state w=p(X)/rho (X) which is allowed to vary with time. We describe and compare different approaches for determining w(t), including a magnitude-redshift (Hubble) diagram, number counts of galaxies and clusters, and CMB anisotropy. We focus particular attention on the use of a sample of several thousand type Ia supernova with redshifts z less than or similar to1.7, as might be gathered by the proposed SNAP satellite. Among other things, we derive optimal strategies for constraining cosmological parameters using type la supernovae. The redshift range z similar or equal to0.2-2 has the most leverage for probing w(X); supernovae and number counts appear to have the most potential to probe dark energy. Because the expansion rate depends upon both w(t) and Omega (M), an independent measurement of the matter density is critical for obtaining the most information about dark energy from cosmological observations. C1 Univ Chicago, Enrico Fermi Inst, Dept Phys, Chicago, IL 60637 USA. Univ Chicago, Dept Astron & Astrophys, Chicago, IL 60637 USA. NASA, Fermilab Astrophys Ctr, Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. RP Univ Chicago, Enrico Fermi Inst, Dept Phys, Chicago, IL 60637 USA. NR 89 TC 303 Z9 304 U1 0 U2 5 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0010 EI 2470-0029 J9 PHYS REV D JI Phys. Rev. D PD DEC 15 PY 2001 VL 64 IS 12 AR 123527 DI 10.1103/PhysRevD.64.123527 PG 20 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 504QJ UT WOS:000172867100037 ER PT J AU Guo, XF Randic, M Basak, SC AF Guo, XF Randic, M Basak, SC TI A novel 2-D graphical representation of DNA sequences of low degeneracy SO CHEMICAL PHYSICS LETTERS LA English DT Article ID H-CURVES; SIMILARITY AB Some 2-D and 3-D graphical representations of DNA sequences have been given by Nandy, Leong and Mogenthaler, and Randic et al., which give visual characterizations of DNA sequences. In this Letter, we introduce a novel graphical representation of DNA sequences by taking four special vectors in 2-D space to represent the four nucleic acid bases in DNA sequences, so that a DNA sequence is denoted on a plane by a successive vector sequence, which is also a directed walk on the plane. It is showed that the novel graphical representation of DNA sequences has lower degeneracy and less overlapping. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Xinjiang Univ, Inst Math & Phys, Urumqi 830046, Xinjiang, Peoples R China. Iowa State Univ Sci & Technol, Ames Lab, EOE, Ames, IA 50011 USA. Univ Minnesota, Nat Resources Res Inst, Duluth, MN 55811 USA. RP Guo, XF (reprint author), Xinjiang Univ, Inst Math & Phys, Urumqi 830046, Xinjiang, Peoples R China. RI Guo, XF/G-3448-2010 NR 22 TC 88 Z9 90 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0009-2614 J9 CHEM PHYS LETT JI Chem. Phys. Lett. PD DEC 14 PY 2001 VL 350 IS 1-2 BP 106 EP 112 DI 10.1016/S0009-2614(01)01246-5 PG 7 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 507YF UT WOS:000173058300016 ER PT J AU Van Dort, HM Knowles, DW Chasis, JA Lee, G Mohandas, N Low, PS AF Van Dort, HM Knowles, DW Chasis, JA Lee, G Mohandas, N Low, PS TI Analysis of integral membrane protein contributions to the deformability and stability of the human erythrocyte membrane SO JOURNAL OF BIOLOGICAL CHEMISTRY LA English DT Article ID ANKYRIN-BINDING; CELL DEFORMABILITY; ANION-EXCHANGER; BAND-3 PROTEIN; SPECTRIN; SKELETON; PHOSPHATIDYLSERINE; SPHEROCYTOSIS; TRANSMEMBRANE; DEFICIENCY AB Three major hypotheses have been proposed to explain the role of membrane-spanning proteins in establishing/maintaining membrane stability. These hypotheses ascribe the essential contribution of integral membrane proteins to (i) their ability to anchor the membrane skeleton to the lipid bilayer, (ii) their capacity to bind and stabilize membrane lipids, and (iii) their ability to influence and regulate local membrane curvature. In an effort to test these hypotheses in greater detail, we have modified both the membrane skeletal and lipid binding interactions of band 3 (the major membrane-spanning and skeletal binding protein of the human erythrocyte membrane) and have examined the impact of these modifications on erythrocyte membrane morphology., deformability, and stability. The desired changes in membrane skeletal and protein-lipid interactions were induced by 1) reaction of the cells with 4,4'-diisothiocyanostilbene-2,2'-disulfonate (DIDS), an inhibitor of band 3-mediated anion transport that dissociates band 3 into dimers (increasing its surface area in contact with lipid) and severs band 3 linkages to the membrane skeleton; 2) a fragment of ankyrin that ruptures the same ankyrin-band 3 bridge to the membrane skeleton, but drives the band 3 subunit equilibrium toward the tetramer (i.e. decreasing the band 3 surface area in contact with lipid); and 3) an antibody to the ankyrin-binding site on band 3 that promotes the same changes in band 3 skeletal and lipid interactions as the ankyrin fragment. We observed that although DIDS induced echinocytic morphological changes in the treated erythrocytes, it had little impact on either membrane deformability or stability. In contrast, resealing of either the ankyrin fragment or anti-band 3 IgG into erythrocytes caused spontaneous membrane fragmentation and loss of deformability/stability. Because these and other new observations cannot all be reconciled with any single hypothesis on membrane stability, we suggest that more than one hypothesis may be operative and provide an explanation of how each might individually contribute to net membrane stability. C1 Purdue Univ, Dept Chem, W Lafayette, IN 47907 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, Berkeley, CA 94720 USA. RP Low, PS (reprint author), Purdue Univ, Dept Chem, W Lafayette, IN 47907 USA. OI Low, Philip/0000-0001-9042-5528 FU NHLBI NIH HHS [HL 31579]; NIDDK NIH HHS [DK 26263]; NIGMS NIH HHS [GM 24417, T32 GM 08296] NR 37 TC 23 Z9 23 U1 1 U2 4 PU AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3996 USA SN 0021-9258 J9 J BIOL CHEM JI J. Biol. Chem. PD DEC 14 PY 2001 VL 276 IS 50 BP 46968 EP 46974 DI 10.1074/jbc.M107855200 PG 7 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 502XR UT WOS:000172768500041 PM 11595743 ER PT J AU Trombettoni, A Smerzi, A AF Trombettoni, A Smerzi, A TI Variational dynamics of Bose-Einstein condensates in deep optical lattices SO JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS LA English DT Article; Proceedings Paper CT International Workshop on Theory of Quantum Gases and Quantum Coherence CY JUN 03-05, 2001 CL SALERNO, ITALY SP European Sci Fdn, INFM, Univ Salerno, Dept Phys, Fac Sci ID ARRAYS AB We study the dynamics of a Bose-Einstein condensate wavepacket trapped in an optical lattice. In the tight-binding limit, the system maps onto a discrete nonlinear Schrodinger equation. Using a collective coordinate approximation, we investigate different dynamical regimes: diffusive (in which the boson wavepacket spreads out), self-trapped (with a self-induced pinning), breathing (where the centre of mass of the wavepacket moves with an oscillating width), and solitonic (in which the wavepacket shape is exactly preserved during the dynamics). C1 Scuola Int Super Studi Avanzati, I-34014 Trieste, Italy. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Los Alamos Natl Lab, Ctr Nonlinear Studies, Los Alamos, NM 87545 USA. RP Trombettoni, A (reprint author), Scuola Int Super Studi Avanzati, Via Beirut 2-4, I-34014 Trieste, Italy. OI Trombettoni, Andrea/0000-0002-1108-4727 NR 23 TC 18 Z9 18 U1 0 U2 1 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 2001 VL 34 IS 23 BP 4711 EP 4720 AR PII S0953-4075(01)28506-X DI 10.1088/0953-4075/34/23/315 PG 10 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 522HQ UT WOS:000173890700016 ER PT J AU Bowler, KC Del Debbio, L Flynn, JM Lacagnina, GN Lesk, VI Maynard, CM Richards, DG AF Bowler, KC Del Debbio, L Flynn, JM Lacagnina, GN Lesk, VI Maynard, CM Richards, DG CA UKQCD Collaboration TI Decay constants of B and D mesons from non-perturbatively improved lattice QCD SO NUCLEAR PHYSICS B LA English DT Article ID NONPERTURBATIVE RENORMALIZATION-CONSTANTS; QUARK EFFECTIVE THEORY; FORM-FACTORS; GAUGE-THEORY; PRECISION COMPUTATION; O(A) IMPROVEMENT; WARD IDENTITIES; QUENCHED QCD; HEAVY; FERMIONS AB The decay constants of B, D and K mesons are computed in quenched lattice QCD at two different values of the coupling. The action and operators are O(a) improved with non-perturbative coefficients. The results are f(B) = 195(6)(-) (+24)(23) MeV, f(D) = 206(4)(-10)(+17) MeV, f(Bs) = 220(6)(-28)(+23) MeV, f(Ds) = 229(3)(-12)(+23) MeV and f(K) = 150(3)(-8)(+12) MeV. Systematic errors are discussed in detail. Results for vector decay constants, flavour symmetry breaking ratios of decay constants, the pseudoscalar-vector mass splitting and D meson masses are also presented. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Edinburgh, Dept Phys & Astron, Edinburgh EH9 3JZ, Midlothian, Scotland. Univ Southampton, Dept Phys & Astron, Southampton SO17 1BJ, Hants, England. Jefferson Lab, Newport News, VA 23606 USA. Old Dominion Univ, Dept Phys, Norfolk, VA 23529 USA. RP Univ Edinburgh, Dept Phys & Astron, Edinburgh EH9 3JZ, Midlothian, Scotland. EM gnl@ph.ed.ac.uk OI Del Debbio, Luigi/0000-0003-4246-3305 NR 54 TC 67 Z9 67 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 14 PY 2001 VL 619 IS 1-3 BP 507 EP 537 DI 10.1016/S0550-3213(01)00511-9 PG 31 WC Physics, Particles & Fields SC Physics GA 504NT UT WOS:000172863300021 ER PT J AU Kumar, S Wesnousky, SG Rockwell, TK Ragona, D Thakur, VC Seitz, GG AF Kumar, S Wesnousky, SG Rockwell, TK Ragona, D Thakur, VC Seitz, GG TI Earthquake recurrence and rupture dynamics of Himalayan Frontal Thrust, India SO SCIENCE LA English DT Article ID CONVERGENCE; COLLISION; KANGRA; NEPAL AB The Black Mango fault is a structural discontinuity that transforms motion between two segments of the active Himalayan Frontal Thrust (HFT) in northwestern India. The Black Mango fault displays evidence of two large surface rupture earthquakes during the past 650 years, subsequent to 1294 A.D. and 1423 A.D., and possibly another rupture at about 260 A.D. Displacement during the last two earthquakes was at minimum 4.6 meters and 2.4 to 4.0 meters, respectively, and possibly larger for the 260 A.D. event. Abandoned terraces of the adjacent Markanda River record uplift due to slip on the underlying HFT of 4.8 +/- 0.9 millimeters per year or greater since the mid-Holocene. The uplift rate is equivalent to rates of fault slip and crustal shortening of 9.6(-3.5)(+7.0) millimeters per year and 8.4(-3.6)(+7.3) millimeters per year, respectively, when it is assumed that the HFT dips 30 degrees +/- 10 degrees. C1 Univ Nevada, Ctr Neotecton Studies, Reno, NV 89557 USA. San Diego State Univ, Dept Geol Sci, San Diego, CA 92182 USA. Wadia Inst Himalayan Geol, Dehra Dun 248001, Uttar Pradesh, India. Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Kumar, S (reprint author), Univ Nevada, Ctr Neotecton Studies, Reno, NV 89557 USA. OI Rockwell, Thomas/0000-0001-5319-6447 NR 19 TC 100 Z9 108 U1 1 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 14 PY 2001 VL 294 IS 5550 BP 2328 EP 2331 DI 10.1126/science.1066195 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 503TT UT WOS:000172817200039 PM 11729266 ER PT J AU Wang, YS Liu, SX Pinto, MR Dattelbaum, DM Schoonover, JR Schanze, KS AF Wang, YS Liu, SX Pinto, MR Dattelbaum, DM Schoonover, JR Schanze, KS TI Excited-state structure and delocalization in ruthenium(II)-bipyridine complexes that contain phenyleneethynylene substituents SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID CHARGE-TRANSFER CHROMOPHORES; EMISSION SPECTRAL PROFILES; ENERGY-GAP LAW; POLYPYRIDINE COMPLEXES; ELECTRON-TRANSFER; INTRAMOLECULAR ELECTRON; LUMINESCENCE PROPERTIES; CONJUGATED POLYMERS; REDOX COUPLES; METAL AB A comprehensive photophysical study has been carried out on the two complexes [(bpy)(2)Ru(4,4 ' -PE-bpy)](2+) and [(bpy)2Ru(5,5 ' -PE-bpy)](2+) (44Ru and 55Ru, respectively, where bpy = 2.2 ' -bipyridine and PE = phenyleneethynylene). The objective of this work is to determine the effect of the phenyleneethynylene substituents on the properties of the metal-to-ligand charge-transfer excited state. The complexes have been characterized by using UV-visible absorption, photoluminescence, and UV-visible and infrared transient absorption spectroscopy. The results indicate that the MLCT excited state is localized on the PE-substituted bpy ligands. Moreover, the photophysical data indicate that in the MLCT excited state the excited electron is delocalized into the PE substituents and the manifestations of the electronic delocalization are larger when the substituents are in the 4,4 ' -positions. C1 Univ Florida, Dept Chem, Gainesville, FL 32611 USA. Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87544 USA. RP Schanze, KS (reprint author), Univ Florida, Dept Chem, POB 117200, Gainesville, FL 32611 USA. RI Schanze, Kirk/A-7200-2009 OI Schanze, Kirk/0000-0003-3342-4080 NR 55 TC 43 Z9 43 U1 0 U2 6 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 13 PY 2001 VL 105 IS 49 BP 11118 EP 11127 DI 10.1021/jp013008j PG 10 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 502CW UT WOS:000172727000023 ER PT J AU Ciraolo, MF Hanson, JC Toby, BH Grey, CP AF Ciraolo, MF Hanson, JC Toby, BH Grey, CP TI Combined X-ray and neutron powder refinement and NMR study of hydrochlorofluorocarbon HCFC-124a (CF2HCF2Cl) binding on NaX SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID SODIUM-Y ZEOLITE; STRUCTURAL CHARACTERIZATION; RAMAN-SPECTROSCOPY; CRYSTAL-STRUCTURE; MAS NMR; DIFFRACTION; CHLOROFORM; CATIONS; BENZENE; ADSORPTION AB The structure of hydrochlorofluorocarbon (HCFC) 124a (CF2HCF2Cl) adsorbed on NaX has been determined at 100 K. by performing simultaneous Rietveld analyses of both X-ray and neutron data. The HCFC molecule is localized above the four rings, and is bound via fluorine atoms on both the CF2H and CF2Cl groups to sodium cations in the SII and SIII' positions. Both this model and the H-1 MAS NMR are consistent with hydrogen bonding between the proton of the HCFC and the framework oxygen. Cations were found at the SI', SII, and SIII' positions, after gas sorption. The positions and occupancies do not differ significantly from those previously reported in the low-temperature structures of NaX, Na-23 MAS NMR demonstrates that the SIII cations in the supercages are mobile at room temperature in the bare zeolite, but that lowering the temperature or gas sorption lock's these cations in place. Variable offset F-19 to Na-23 cross polarization (CP) MAS NMR spectroscopy was used to probe fluorocarbon-cation proximity. More efficient CP was observed from the fluorine atoms on the CF2H group, in comparison to the CF2Cl fluorine atoms. This was ascribed to the larger number of cations coordinated to this group. This is consistent with the model obtained from the diffraction studies. where the CF2H group is bound to two cations, while the CF2Cl group is bound to only one cation. C1 SUNY Stony Brook, Dept Chem, Stony Brook, NY 11794 USA. Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. NIST, Ctr Neutron Res, Gaithersburg, MD 20899 USA. RP Grey, CP (reprint author), SUNY Stony Brook, Dept Chem, Stony Brook, NY 11794 USA. RI Hanson, jonathan/E-3517-2010; Toby, Brian/F-3176-2013 OI Toby, Brian/0000-0001-8793-8285 NR 32 TC 16 Z9 16 U1 1 U2 7 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 13 PY 2001 VL 105 IS 49 BP 12330 EP 12337 DI 10.1021/jp0120413 PG 8 WC Chemistry, Physical SC Chemistry GA 502CY UT WOS:000172727200015 ER PT J AU Zazubovich, V Tibe, I Small, GJ AF Zazubovich, V Tibe, I Small, GJ TI Bacteriochlorophyll a Franck-Condon factors for the S-0 -> S-1(Q(y)) transition SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID PHOTOSYNTHETIC ANTENNA COMPLEXES; TEMPERATURE-DEPENDENT ABSORPTION; STEADY-STATE SPECTRA; ENERGY-TRANSFER; PROSTHECOCHLORIS-AESTUARII; FMO-COMPLEX; INTEGRAL INTERPRETATION; DISPERSIVE KINETICS; EXCITON SIMULATIONS; OPTICAL-SPECTRA AB Pseudovibronic satellite hole-burning spectroscopy of bacteriochlorophyll a (BChl a) in two glasses at 5 K was used to determine the Franck-Condon (FC) factors for 56 one-quantum (0 --> 1) vibrational transitions that lie between 160 and 1600 cm(-1). As in the case of Chl a (Pieper, L et al. J, Phys. Chem. B 1999, 103, 2319). the FC factors are small. ranging between 0.05 and 0,0007 (uncertainty approximate to +/- 20%). The FC factors, together with the experimentally determined inhomogeneous site excitation distribution function for the zerophonon line and linear electron-phonon coupling parameters. account well for the S-0 --> Q(y) absorption spectra. Thus. the FC factors are accurate enough to be used in quantum mechanical calculations of excitation energy transfer rates in photosynthetic antenna complexes (with their intrinsic Structural heterogeneity) exhibiting excitonic coupling that ranges between weak and strong. The BChl a FC factors determined by hole burning are compared with those obtained by fluorescence line narrowing spectroscopy (Wendling, M.; et al. J. Phys. Chem. B 2000, 104, 5825). The latter, which are about a factor of 5 smaller than those determined by hole burning, are too small to account for the vibronic contribution to the So absorption spectrum. The discrepancy between the two sets of FC factors is discussed. C1 US DOE, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Chem, Ames, IA 50011 USA. RP Small, GJ (reprint author), US DOE, Ames Lab, Ames, IA 50011 USA. NR 48 TC 36 Z9 36 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 13 PY 2001 VL 105 IS 49 BP 12410 EP 12417 DI 10.1021/jp012804m PG 8 WC Chemistry, Physical SC Chemistry GA 502CY UT WOS:000172727200024 ER PT J AU Schrope, M AF Schrope, M TI Which way to energy utopia? SO NATURE LA English DT News Item C1 US DOE, Hydrogen Program, Washington, DC 20585 USA. RP Schrope, M (reprint author), US DOE, Hydrogen Program, Washington, DC 20585 USA. NR 0 TC 43 Z9 46 U1 0 U2 7 PU MACMILLAN PUBLISHERS LTD PI LONDON PA PORTERS SOUTH, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD DEC 13 PY 2001 VL 414 IS 6865 BP 682 EP 684 DI 10.1038/414682a PG 3 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 501GD UT WOS:000172676200012 PM 11742361 ER PT J AU Eschrich, I Kruger, H Simon, J Vorwalter, K Alkhazov, G Atamantchouk, AG Balatz, MY Bondar, NF Cooper, PS Dauwe, LJ Davidenko, GV Dersch, U Dirkes, G Dolgolenko, AG Dzyubenko, GB Edelstein, R Emediato, L Endler, AMF Engelfried, J Escobar, CO Evdokimov, AV Filimonov, IS Garcia, FG Gaspero, M Giller, I Golovtsov, VL Gouffon, P Gulmez, E Kangling, H Iori, M Jun, SY Kaya, M Kilmer, J Kim, VT Kochenda, LM Konigsmann, K Konorov, I Kozhevnikov, AP Krivshich, AG Kubantsev, MA Kubarovsky, VP Kulyavtsev, AI Kuropatkin, NP Kurshetsov, VF Kushnirenko, A Kwan, S Lach, J Lamberto, A Landsberg, LG Larin, I Leikin, EM Li, YS Luksys, M Lungov, T Maleev, VP Mao, D Mao, CS Mao, ZL Masciocchi, S Mathew, P Mattson, M Matveev, V McCliment, E Moinester, MA Molchanov, VV Morelos, A Nelson, KD Nemitkin, AV Neoustroev, PV Newsom, C Nilov, AP Nurushev, SB Ocherashvili, A Onel, Y Ozel, E Ozkorucuklu, S Penzo, A Petrenko, SV Pogodin, P Povh, B Procario, M Prutskoi, VA Ramberg, E Rappazzo, GF Razmyslovich, BV Rud, VI Russ, J Scheglov, Y Schiavon, P Sitnikov, AI Skow, D Smith, VJ Srivastava, M Steiner, V Stepanov, V Stutte, L Svoiski, M Terentyev, NK Thomas, GP Uvarov, LN Vasiliev, AN Vavilov, DV Verebryusov, VS Victorov, VA Vishnyakov, VE Vorobyov, AA You, J Zhao, WH Zheng, SC Zukanovich-Funchal, R AF Eschrich, I Kruger, H Simon, J Vorwalter, K Alkhazov, G Atamantchouk, AG Balatz, MY Bondar, NF Cooper, PS Dauwe, LJ Davidenko, GV Dersch, U Dirkes, G Dolgolenko, AG Dzyubenko, GB Edelstein, R Emediato, L Endler, AMF Engelfried, J Escobar, CO Evdokimov, AV Filimonov, IS Garcia, FG Gaspero, M Giller, I Golovtsov, VL Gouffon, P Gulmez, E Kangling, H Iori, M Jun, SY Kaya, M Kilmer, J Kim, VT Kochenda, LM Konigsmann, K Konorov, I Kozhevnikov, AP Krivshich, AG Kubantsev, MA Kubarovsky, VP Kulyavtsev, AI Kuropatkin, NP Kurshetsov, VF Kushnirenko, A Kwan, S Lach, J Lamberto, A Landsberg, LG Larin, I Leikin, EM Li, YS Luksys, M Lungov, T Maleev, VP Mao, D Mao, CS Mao, ZL Masciocchi, S Mathew, P Mattson, M Matveev, V McCliment, E Moinester, MA Molchanov, VV Morelos, A Nelson, KD Nemitkin, AV Neoustroev, PV Newsom, C Nilov, AP Nurushev, SB Ocherashvili, A Onel, Y Ozel, E Ozkorucuklu, S Penzo, A Petrenko, SV Pogodin, P Povh, B Procario, M Prutskoi, VA Ramberg, E Rappazzo, GF Razmyslovich, BV Rud, VI Russ, J Scheglov, Y Schiavon, P Sitnikov, AI Skow, D Smith, VJ Srivastava, M Steiner, V Stepanov, V Stutte, L Svoiski, M Terentyev, NK Thomas, GP Uvarov, LN Vasiliev, AN Vavilov, DV Verebryusov, VS Victorov, VA Vishnyakov, VE Vorobyov, AA You, J Zhao, WH Zheng, SC Zukanovich-Funchal, R TI Measurement of the Sigma(-) charge radius by Sigma(-)-electron elastic scattering SO PHYSICS LETTERS B LA English DT Article DE electromagnetic form factors; elastic scattering; hadron-induced elastic scattering at high energy; hyperons; electron-Sigma(-) elastic scattering; Sigma(-) form factor; Sigma(-) charge radius; hadron strong and electromagnetic radii AB The Sigma (-) mean squared charge radius has been measured in the space-like Q(2) range 0.035--0.105 GeV2/c(2) by elastic scattering of a Sigma (-) beam off atomic electrons. The measurement was per-formed with the SELEX (E781) spectrometer using the Fermilab hyperon beam at a mean energy of 610 GeV/c We obtain Sigma (-) =(0.61 +/- 0.12(stat.) +/- 0.09(syst.)) fm(2). The proton and pi (-) charge radii were measured as well and are consistent with results of other experiments. Our result agrees with the recently measured strong interaction radius of the Sigma (-). (C) 2001 Elsevier Science B.V. All rights reserved. C1 Max Planck Inst Kernphys, D-69117 Heidelberg, Germany. Ball State Univ, Muncie, IN 47306 USA. Bogazici Univ, TR-80815 Bebek, Turkey. Carnegie Mellon Univ, Pittsburgh, PA 15213 USA. Ctr Brasileiro Pesquisas Fis, BR-22290 Rio De Janeiro, Brazil. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Inst High Energy Phys, Protvino, Russia. Inst High Energy Phys, Beijing 100039, Peoples R China. Inst Theoret & Expt Phys, Moscow 117259, Russia. Moscow MV Lomonosov State Univ, Moscow, Russia. Petersburg Nucl Phys Inst, St Petersburg, Russia. Tel Aviv Univ, IL-69978 Tel Aviv, Israel. Univ Autonoma San Luis Potosi, San Luis Potosi, Mexico. Univ Fed Paraiba, BR-58059900 Joao Pessoa, Paraiba, Brazil. Univ Bristol, Bristol BS8 1TL, Avon, England. Univ Iowa, Iowa City, IA 52242 USA. Univ Michigan, Flint, MI 48502 USA. Univ Roma La Sapienza, I-00185 Rome, Italy. Ist Nazl Fis Nucl, I-00185 Rome, Italy. Univ Sao Paulo, BR-05508900 Sao Paulo, Brazil. Univ Trieste, I-34127 Trieste, Italy. Ist Nazl Fis Nucl, I-34127 Trieste, Italy. RP Eschrich, I (reprint author), Univ London Imperial Coll Sci Technol & Med, London SW7 2BZ, England. RI Zukanovich Funchal, Renata/C-5829-2013; Russ, James/P-3092-2014; Gulmez, Erhan/P-9518-2015; Gouffon, Philippe/I-4549-2012; Maleev, Victor/R-4140-2016; OI Zukanovich Funchal, Renata/0000-0001-6749-0022; Russ, James/0000-0001-9856-9155; Gulmez, Erhan/0000-0002-6353-518X; Gouffon, Philippe/0000-0001-7511-4115; iori, maurizio/0000-0002-6349-0380 NR 19 TC 38 Z9 38 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 13 PY 2001 VL 522 IS 3-4 BP 233 EP 239 DI 10.1016/S0370-2693(01)01285-0 PG 7 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 500AB UT WOS:000172602500005 ER PT J AU Chung, GY Williams, JR Tin, CC McDonald, K Farmer, D Chanana, RK Pantelides, ST Holland, OW Feldman, LC AF Chung, GY Williams, JR Tin, CC McDonald, K Farmer, D Chanana, RK Pantelides, ST Holland, OW Feldman, LC TI Interface state density and channel mobility for 4H-SiC MOSFETs with nitrogen passivation SO APPLIED SURFACE SCIENCE LA English DT Article; Proceedings Paper CT Spring Meeting of the European-Materials-Research-Society CY JUN 05-08, 2001 CL STRASBOURG, FRANCE SP European Mat Res Soc DE interface states; mobility; silicon carbide; MOSFETs; nitration; threshold voltage ID SILICON-CARBIDE; BAND EDGES; POLYTYPE AB Interface state density and channel mobility have been characterized for 4H-SiC MOSFETs fabricated with dry thermal oxides and subsequently passivated with nitric oxide. The interface trap density at 0.1 eV below the conduction band edge decreases from approximately 8 x 10(12) to 1 x 10(12) eV(-1) cm(-2) following anneals in nitric oxide (NO) at 1175 degreesC for 2 h. The room temperature field effect channel mobility increases by an order of magnitude to approximately 35 cm(2)/V s following the passivation anneal. The field effect channel mobility of passivated MOSFETs shows almost no change with increasing temperature, while the mobility for unpassivated devices increases with increasing temperature and is thermally activated (similar toT(1.9)) due to decreased Coulomb scattering by electrons trapped at the acceptor-like interface states near the conduction band. Over the temperature range 300-473 K, threshold voltage changes of about -0.8 and -3.7 V, respectively, are observed for devices processed with and without NO passivation. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Sterling Semicond Inc, Tampa, FL 33619 USA. Auburn Univ, Dept Phys, Auburn, AL 36849 USA. Vanderbilt Univ, Dept Phys & Astron, Nashville, TN 37235 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Chung, GY (reprint author), Sterling Semicond Inc, 4301 Cragmont Dr, Tampa, FL 33619 USA. RI Tin, Chin-Che/A-9122-2012 NR 14 TC 17 Z9 18 U1 1 U2 8 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0169-4332 J9 APPL SURF SCI JI Appl. Surf. Sci. PD DEC 12 PY 2001 VL 184 IS 1-4 BP 399 EP 403 DI 10.1016/S0169-4332(01)00684-5 PG 5 WC Chemistry, Physical; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Chemistry; Materials Science; Physics GA 506YV UT WOS:000173000100068 ER PT J AU Zhu, XY Jun, Y Staarup, DR Major, RC Danielson, S Boiadjiev, V Gladfelter, WL Bunker, BC Guo, A AF Zhu, XY Jun, Y Staarup, DR Major, RC Danielson, S Boiadjiev, V Gladfelter, WL Bunker, BC Guo, A TI Grafting of high-density poly(ethylene glycol) monolayers on Si(111) SO LANGMUIR LA English DT Article ID SELF-ASSEMBLED MONOLAYERS; PROTEIN ADSORPTION; SILICON SURFACES; SPECTROSCOPY; OXIDE) AB A strategy has been developed for the grafting of poly(ethylene glycol) (PEG) monolayers onto the atomically flat Si(111) surface. This process involves the direct interaction of the HO-functional group on PEG with a chlorine-terminated silicon surface. The resulting monolayers show exceptional flatness, with mean roughness on the angstrom scale. Film thickness is determined by ellipsometry, X-ray photoelectron spectroscopy, and atomic force microscopy. Results for different molecular weights reveal that the grafted PEG molecules are in a brushlike configuration at low molecular weight (MW = 200, 300) and a more coil-like configuration at higher molecular weight (MW = 1000, 2000). The surface density of grafted PEG molecules is significantly higher than those reported in the literature and decreases with increasing molecular weight, from 92% at MW = 300 to 35% at MW = 2000. Both the brushlike and the coil-like configurations show excellent properties of protein resistance. C1 Univ Minnesota, Dept Chem, Minneapolis, MN 55455 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. Univ Minnesota, Dept Neurosci, Minneapolis, MN 55455 USA. RP Zhu, XY (reprint author), Univ Minnesota, Dept Chem, 207 Pleasant St SE, Minneapolis, MN 55455 USA. RI Jun, F-5077-2010/F-5077-2010 NR 21 TC 92 Z9 93 U1 3 U2 18 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0743-7463 J9 LANGMUIR JI Langmuir PD DEC 11 PY 2001 VL 17 IS 25 BP 7798 EP 7803 DI 10.1021/la010672i PG 6 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 499VJ UT WOS:000172590800015 ER PT J AU Peurrung, A Arthur, R Elovich, R Geelhood, B Kouzes, R Pratt, S Scheele, R Sell, R AF Peurrung, A Arthur, R Elovich, R Geelhood, B Kouzes, R Pratt, S Scheele, R Sell, R TI The 871 keV gamma ray from O-17 and the identification of plutonium oxide SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article DE plutonium oxide; O-17; weapons attributes; disarmament AB Disarmament agreements and discussions between the United States and the Russian Federation for reducing the number of stockpiled nuclear weapons require verification of the origin of materials as having come from disassembled weapons. This has resulted in the identification of measurable "attributes" that characterize such materials. It has been proposed that the 871 keV gamma ray of O-17 can be observed as an indicator of the unexpected presence of plutonium oxide, as opposed to plutonium metal, in such materials. We have shown that the observation of the 871 keV gamma ray is not a specific indicator of the presence of the oxide, but rather indicates the presence of nitrogen. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Kouzes, R (reprint author), Pacific NW Natl Lab, MS P8-20,POB 999, Richland, WA 99352 USA. NR 8 TC 5 Z9 5 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 11 PY 2001 VL 474 IS 3 BP 285 EP 293 DI 10.1016/S0168-9002(01)00886-5 PG 9 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 500CZ UT WOS:000172609500009 ER PT J AU Seong, MJ Hanna, MC Mascarenhas, A AF Seong, MJ Hanna, MC Mascarenhas, A TI Composition dependence of Raman intensity of the nitrogen localized vibrational mode in GaAs1-xNx SO APPLIED PHYSICS LETTERS LA English DT Article ID TRANSITIONS; SCATTERING; GAAS AB We have investigated the nitrogen-localized vibrational mode (LVM) Raman intensity and its frequency (omega (LVM)) as a function of nitrogen concentration in GaAs1-xNx (x less than or equal to0.04) at 300 K. The normalized Raman intensity of nitrogen LVM with respect to that of GaAs-LO phonon as well as omega (LVM) exhibits a remarkable linear dependence on the nitrogen concentration for x less than or equal to0.03. This provides excellent calibration to determine nitrogen composition not only in the ternary alloy GaAs1-xNx but also in the quaternaries such as Ga1-yInyAs1-xNx. (C) 2001 American Institute of Physics. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Seong, MJ (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 14 TC 38 Z9 38 U1 1 U2 6 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD DEC 10 PY 2001 VL 79 IS 24 BP 3974 EP 3976 DI 10.1063/1.1424469 PG 3 WC Physics, Applied SC Physics GA 498BC UT WOS:000172489100023 ER PT J AU Platt, CL Berkowitz, AE David, S Fullerton, EE Jiang, JS Bader, SD AF Platt, CL Berkowitz, AE David, S Fullerton, EE Jiang, JS Bader, SD TI Reversal modes of exchange-spring magnets revealed by torque magnetometry SO APPLIED PHYSICS LETTERS LA English DT Article ID ANISOTROPY; STABILITY; FILMS; CO AB Torque magnetometry measurements and related micromagnetic simulations are reported for SmCo/Fe exchange-spring films with uniaxial in-plane easy axis of magnetization. Rotating an applied magnetic field in plane, away from the easy direction, gives rise to an irreversible jump in the torque curves at a critical angle. The jump is associated with a switch in chirality of the magnetization spiral structure that develops in the magnetically soft Fe layer, pinned at the interface with the hard SmCo layer. Two reversal modes of the chirality are identified, one at low fields due to an in-plane untwisting of the spiral, and the other at high fields, due to an out-of-plane fanning of the spiral. (C) 2001 American Institute of Physics. C1 Univ Calif San Diego, Ctr Magnet Recording Res, La Jolla, CA 92093 USA. IBM Corp, Almaden Res Ctr, San Jose, CA 95120 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Platt, CL (reprint author), Seagate Technol, River Pk Commons,Suite 550, Pittsburgh, PA 15203 USA. RI Bader, Samuel/A-2995-2013; Fullerton, Eric/H-8445-2013 OI Fullerton, Eric/0000-0002-4725-9509 NR 15 TC 17 Z9 18 U1 1 U2 8 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD DEC 10 PY 2001 VL 79 IS 24 BP 3992 EP 3994 DI 10.1063/1.1425432 PG 3 WC Physics, Applied SC Physics GA 498BC UT WOS:000172489100029 ER PT J AU Zhang, Y Kinion, D Chen, J Clarke, J Hinks, DG Crabtree, GW AF Zhang, Y Kinion, D Chen, J Clarke, J Hinks, DG Crabtree, GW TI MgB2 tunnel junctions and 19 K low-noise dc superconducting quantum interference devices SO APPLIED PHYSICS LETTERS LA English DT Article AB Point contact junctions made from two pieces of MgB2 can be adjusted to exhibit either superconductor-insulator-superconductor (SIS) or superconductor-normal metal-superconductor (SNS) current-voltage characteristics. The SIS characteristics are in good agreement with the standard tunneling model for s-wave superconductors, and yield an energy gap of (2.02+/-0.08) meV. The SNS characteristics are in good agreement with the predictions of the resistively-shunted junction model. DC superconducting quantum interference devices made from two SNS junctions yield magnetic flux and field noise as low as 4 mu Phi (0) Hz(-1/2) and 35 fT Hz(-1/2) at 19 K; Phi (0) is the flux quantum. (C) 2001 American Institute of Physics. C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Zhang, Y (reprint author), Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. NR 17 TC 47 Z9 49 U1 0 U2 6 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD DEC 10 PY 2001 VL 79 IS 24 BP 3995 EP 3997 DI 10.1063/1.1424465 PG 3 WC Physics, Applied SC Physics GA 498BC UT WOS:000172489100030 ER PT J AU Feldmann, DM Larbalestier, DC Verebelyi, DT Zhang, W Li, Q Riley, GN Feenstra, R Goyal, A Lee, DF Paranthaman, M Kroeger, DM Christen, DK AF Feldmann, DM Larbalestier, DC Verebelyi, DT Zhang, W Li, Q Riley, GN Feenstra, R Goyal, A Lee, DF Paranthaman, M Kroeger, DM Christen, DK TI Inter- and intragrain transport measurements in YBa2Cu3O7-x deformation textured coated conductors SO APPLIED PHYSICS LETTERS LA English DT Article ID GRAIN-BOUNDARIES; CALCIUM; DENSITY; FILMS AB Using photolithography, links for transport measurement have been placed across individual Ni grain boundaries and within individual Ni grains on several coated conductor samples. The typical Ni grain size is similar to 50 mum, while the YBa2Cu3O7-x grains are submicron in size. It is found that the intragrain J(c)(0 T,77 K) can exceed 5 MA/cm(2), thus showing that present coated conductor J(c) values are not significantly limited by the intragrain J(c). Inter- and intragrain J(c) values ranged from one-half to more than four times full-width measured values, demonstrating that current percolates through the conductor. The misorientation angle dependence of J(c) fits well with previous studies of [001] tilt SrTiO3 bicrystals. (C) 2001 American Institute of Physics. C1 Univ Wisconsin, Ctr Appl Superconduct, Madison, WI 53706 USA. Amer Superconductor, Westborough, MA 01581 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Feldmann, DM (reprint author), Univ Wisconsin, Ctr Appl Superconduct, 1500 Johnson Dr, Madison, WI 53706 USA. RI Paranthaman, Mariappan/N-3866-2015; Larbalestier, David/B-2277-2008 OI Paranthaman, Mariappan/0000-0003-3009-8531; Larbalestier, David/0000-0001-7098-7208 NR 12 TC 37 Z9 37 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 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD DEC 10 PY 2001 VL 79 IS 24 BP 3998 EP 4000 DI 10.1063/1.1425952 PG 3 WC Physics, Applied SC Physics GA 498BC UT WOS:000172489100031 ER PT J AU Keck, JW Craig, WW Hailey, CJ Harrison, F Hong, JS Kahn, SM Lubin, PM McLean, R Pivovaroff, MJ Seiffert, M Wurtz, R Ziock, KP AF Keck, JW Craig, WW Hailey, CJ Harrison, F Hong, JS Kahn, SM Lubin, PM McLean, R Pivovaroff, MJ Seiffert, M Wurtz, R Ziock, KP TI Long-term multiwavelength observations of GRS 1758-258 and the advection-dominated accretion flow model SO ASTROPHYSICAL JOURNAL LA English DT Article DE accretion, accretion disks; black hole physics; gamma rays : observations; radio continuum : stars; stars : individual (GRS 1758-258); X-rays : stars ID X-RAY SOURCE; BLACK-HOLE; SOURCE GRS-1758-258; COMPTONIZATION MODELS; INTERSTELLAR-MEDIUM; NEUTRON-STARS; GX-339-4; 1E-1740.7-2942; STATE; SPECTROSCOPY AB We present a long-term multiwavelength light curve of Galactic black hole candidate GRS 1758-258 by combining previously published and archival data from Granat, ROSAT, the Compton Gamma Ray Observatory, the Rossi X-Ray Timing Explorer, BeppoSAX, ASCA, EXOSAT, and the Very Large Array. In addition, we include the first spectral results from the balloon-borne Gamma-Ray Arcminute Telescope Imaging System (GRAT IS). In light of divergent analyses of the 1991-1993 ROSAT observations, we have reanalyzed these data; we find that the soft X-rays track the hard X-rays and that the fits require no blackbody component-indicating that GRS 1758-258 did not go to the high state in 1993. We offer an interpretation of these long-baseline data based on the advection-dominated accretion flow (ADAF) model for a system with m over dot less than or similar to m over dot(crit). We find that the 1990-1993 coeval hard and soft X-ray observations support the ADAF predictions. We discuss a new way to constrain black hole mass with spectral data and the ADAF theory and apply this technique to GRS 1758-258 to find M (1) greater than or similar to 8-9 M. at an assumed distance of 8.5 kpc. Further investigations of the ADAF model allow us to evaluate the model critically against the 1996 data and flux-flux diagram of Barret, McClintock, & Grindlay and to understand the limits of the latter's "X-ray burster box." C1 Columbia Univ, Columbia Astrophys Lab, New York, NY 10027 USA. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. CALTECH, Space Radiat Lab, Pasadena, CA 91125 USA. Univ Calif Santa Barbara, Dept Phys, Santa Barbara, CA 93106 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. RP Keck, JW (reprint author), Columbia Univ, Columbia Astrophys Lab, 538 W 120th St, New York, NY 10027 USA. RI Pivovaroff, Michael/M-7998-2014 OI Pivovaroff, Michael/0000-0001-6780-6816 NR 56 TC 6 Z9 6 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD DEC 10 PY 2001 VL 563 IS 1 BP 301 EP 312 DI 10.1086/323686 PN 1 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 504JC UT WOS:000172852700029 ER PT J AU Flores, A Auer, LH Koenigsberger, G Cardona, O AF Flores, A Auer, LH Koenigsberger, G Cardona, O TI The wind-wind collision region of the Wolf-Rayet binary V444 Cygni: How much optical line emission does it produce? SO ASTROPHYSICAL JOURNAL LA English DT Article DE binaries : close; stars : individual (V444 Cygni); stars : winds, outflows; stars : Wolf-Rayet ID SPECTROSCOPIC MICROSCOPE; COLLIDING WINDS; STELLAR WINDS; STAR WINDS; MASS-LOSS; V444-CYGNI; CONSTRAINTS; SYSTEMS; MODELS AB We model the emission-line profile variations that are expected to be produced by physical and wind eclipses in the Wolf-Rayet (W-R + O) binary system V444 Cyg. A comparison of the theoretical profiles with the He II 4686 Angstrom line observed in V444 Cyg allows us to isolate the effects that are likely to be due to the wind-wind collision region in this particular line. We estimate that the wind-wind collision region contributes no more than similar to 12% of the equivalent width of the emission line, with smaller values during elongations, when part of the shock cone is being eclipsed by the O star. The upper limit implies a maximum contribution from the wind-wind collision region of similar to1 x 10(35) ergs s(-1) to the total luminosity of He II 4686 Angstrom line. Using the analytical solution of Canto et al., we find that the bulk of this emission arises along the shock cone walls where the flow velocity is similar to 800 km s(-1), at a distance of similar to8 R. from the O star's surface, and at theta = 65 degrees -75 degrees from the line joining the centers of the two stars, with origin in the O star. The derived surface density of this region is sigma = 0.22 g cm(-2), which, together with the He II 4686 Angstrom luminosity, indicates that the thickness of the shock lies in the range 2-10 x 10(10) cm and the total density is 1-6 x 10(12) cm(-3). C1 Inst Nacl Astrofis Opt & Elect, Puebla, Mexico. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Natl Autonomous Univ Mexico, Inst Astron, Mexico City 04510, DF, Mexico. RP Flores, A (reprint author), Inst Nacl Astrofis Opt & Elect, Puebla, Mexico. NR 31 TC 9 Z9 9 U1 1 U2 2 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD DEC 10 PY 2001 VL 563 IS 1 BP 341 EP 350 DI 10.1086/323774 PN 1 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 504JC UT WOS:000172852700034 ER PT J AU Gong, ZG Dappen, W Nayfonov, A AF Gong, ZG Dappen, W Nayfonov, A TI Effects of heavy elements and excited states in the equation of state of the solar interior SO ASTROPHYSICAL JOURNAL LA English DT Article DE atomic processes; equation of state; stars : evolution; stars : interiors; Sun : helioseismology ID STELLAR ENVELOPES; PARTITION-FUNCTION; THERMODYNAMIC QUANTITIES; MHD EQUATION; MODELS; DIFFUSION; IONIZATION; OPAL; OSCILLATIONS; CONSTRAINTS AB Although 98% of the solar material consists of hydrogen and helium, the remaining chemical elements contribute in a discernible way to the thermodynamic quantities. An adequate treatment of the heavy elements and their excited states is important for solar models that are subject to the stringent requirements of helioseismology. The contribution of various heavy elements in a set of thermodynamic quantities has been examined. Characteristic features that can trace individual heavy elements in the adiabatic exponent gamma (1) = (partial derivative ln p/partial derivative ln rho)(s) (s being specific entropy), and hence in the adiabatic sound speed, were searched. It has emerged that prominent signatures of individual elements exist and that these e+ects are greatest in the ionization zones, typically located near the bottom of the convection zone. The main result is that part of the features found here depend strongly on both the given species (atom or ion) and its detailed internal partition function, whereas other features only depend on the presence of the species itself, not on details such as the internal partition function. The latter features are obviously well suited for a helioseismic abundance determination, while the former features present a unique opportunity to use the Sun as a laboratory to test the validity of physical theories of partial ionization in a relatively dense and hot plasma. This domain of plasma physics has so far no competition from terrestrial laboratories. Another, quite general, finding of this work is that the inclusion of a relatively large number of heavy elements has a tendency to smear out individual features. This affects both the features that determine the abundance of elements and the ones that identify physical effects. This property alleviates the task of solar modelers because it helps to construct a good working equation of state that is relatively free of the uncertainties from basic physics. By the same token, it makes more difficult the reverse task, which is constraining physical theories with the help of solar data. C1 Univ So Calif, Dept Phys & Astron, Los Angeles, CA 90089 USA. Lawrence Livermore Natl Lab, Inst Geophys & Planetary Phys, Livermore, CA 94550 USA. RP Gong, ZG (reprint author), Univ So Calif, Dept Phys & Astron, Los Angeles, CA 90089 USA. NR 45 TC 10 Z9 10 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD DEC 10 PY 2001 VL 563 IS 1 BP 419 EP 433 DI 10.1086/323883 PN 1 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 504JC UT WOS:000172852700043 ER PT J AU Gu, MF Kahn, SM Savin, DW Behar, E Beiersdorfer, P Brown, GV Liedahl, DA Reed, KJ AF Gu, MF Kahn, SM Savin, DW Behar, E Beiersdorfer, P Brown, GV Liedahl, DA Reed, KJ TI Laboratory measurements of iron L-shell emission: 3 -> 2 transitions of Fe XXI-XXIV between 10.5 and 12.5 angstrom SO ASTROPHYSICAL JOURNAL LA English DT Article DE atomic data; atomic processes; line : formation; X-rays : general ID BEAM ION-TRAP; X-RAY SPECTROMETER; ELECTRON-BEAM; DIELECTRONIC-RECOMBINATION; CROSS-SECTIONS; LINE EMISSION; EXCITATION; SPECTRUM; PLASMA AB Using the electron beam ion trap EBIT-II facility at Lawrence Livermore National Laboratory, we have measured the iron L-shell spectrum between 10.5 and 12.5 Angstrom for Fe XXI-XXIV with a spectral resolution of similar to 30 m Angstrom. The relative line intensities of strong 3 --> 2 transitions for each charge state are measured as functions of electron energy and compared to distorted wave (DW) calculations. The contributions of resonant processes, namely, resonant excitation (RE) and spectroscopically unresolved dielectronic recombination (DR) satellites, are investigated. The RE contributions are shown to be less than the experimental and theoretical uncertainties for plasma in collisional ionization equilibrium. The unresolved DR satellites, however, enhance the emissivities of almost all lines, some by as large as 15%, consistent with our earlier measurements for Fe XXIV. The DW results agree with our measurements to better than 20% under the condition of collisional ionization equilibrium. The line emissivities in the widely used spectral synthesis model, MEKAL, are also compared to our measurements and are found to be discrepant at a greater than 20% level for some lines. C1 Columbia Univ, Dept Phys, New York, NY 10027 USA. Columbia Univ, Columbia Astrophys Lab, New York, NY 10027 USA. Lawrence Livermore Natl Lab, Dept Phys & Space Technol, Livermore, CA 94550 USA. RP Gu, MF (reprint author), Columbia Univ, Dept Phys, 538 W 120th St, New York, NY 10027 USA. RI Savin, Daniel/B-9576-2012 OI Savin, Daniel/0000-0002-1111-6610 NR 27 TC 22 Z9 23 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD DEC 10 PY 2001 VL 563 IS 1 BP 462 EP 471 DI 10.1086/323683 PN 1 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 504JC UT WOS:000172852700046 ER PT J AU Jung, KT Bell, AT AF Jung, KT Bell, AT TI An in situ infrared study of dimethyl carbonate synthesis from carbon dioxide and methanol over zirconia SO JOURNAL OF CATALYSIS LA English DT Article ID AEROGEL CATALYSTS; METAL-OXIDES; MONOCLINIC ZIRCONIA; SURFACE-ACIDITY; ADSORPTION; CU/ZRO2/SIO2; MOLECULES; CU/SIO2; ZRO2; GAS AB The mechanism of dimethyl carbonate (DMC) synthesis from methanol and carbon dioxide over monoclinic zirconia has been investigated using in situ infrared spectroscopy. The dissociative adsorption of methanol occurs more slowly than the adsorption of carbon dioxide, but the species formed from methanol are bound more strongly. On adsorption, the oxygen atom of methanol binds to coordinately unsaturated Zr4+ cations present at the catalyst surface. Rapid dissociation of the adsorbed methanol leads to the formation of a methoxide group (Zr-OCH3) and the release of a proton, which reacts with a surface hydroxyl group to produce water. Carbon dioxide inserts into the Zr-O bond of the methoxide to form a mondentate methyl carbonate group (Zr-OC(O)OCH3). It is proposed that this process is facilitated by the interactions of C and O atoms in CO2 with Lewis acid-base pairs of sites (Zr4+O2-) on the surface of the catalyst. Methyl carbonate species can also be produced via the reaction of methanol with carbon dioxide adsorbed in the form of bicarbonate species, but this process is slower than that involving the reaction of carbon dioxide with methoxide species. DMC is formed by reaction of the methyl carbonate species with methanol, a process that results in the transfer of a methyl group to the carbonate and restores a hydroxyl group to the zirconia surface. The decomposition of DMC on monoclinic zirconia has also been investigated and has been observed to occur via the reverse of the processes described for the synthesis of DMC. (C) 2001 Elsevier Science. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Chem Engn, Berkeley, CA 94720 USA. RP Bell, AT (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA. OI Bell, Alexis/0000-0002-5738-4645 NR 45 TC 85 Z9 90 U1 9 U2 71 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0021-9517 J9 J CATAL JI J. Catal. PD DEC 10 PY 2001 VL 204 IS 2 BP 339 EP 347 DI 10.1006/jcat.2001.3411 PG 9 WC Chemistry, Physical; Engineering, Chemical SC Chemistry; Engineering GA 505XP UT WOS:000172941100009 ER PT J AU Bdzil, JB Stewart, DS Jackson, TL AF Bdzil, JB Stewart, DS Jackson, TL TI Program burn algorithms based on detonation shock dynamics: Discrete approximations of detonation flows with discontinuous front models SO JOURNAL OF COMPUTATIONAL PHYSICS LA English DT Article ID EFFICIENT IMPLEMENTATION; NUMERICAL-SIMULATION; SCHEMES AB In the design of explosive systems, the generic problem that one must consider is the propagation of a well-developed detonation wave sweeping through an explosive charge with a complex shape. At a given instant of time, the lead detonation shock is a surface that occupies a region of the explosive and has a dimension that is characteristic of the explosive device, typically on the scale of meters. The detonation shock is powered by a detonation reaction zone. sitting immediately behind the shock, which is on the scale of I mm or less. Thus, the ratio of the reaction zone thickness to the device dimension is on the order of 1/1000 or less. This scale disparity can lead to great difficulties in computing three-dimensional detonation dynamics. An attack on the dilemma in the computation of detonation systems has led to the invention of subscale models for a propagating detonation front that we refer to herein as program burn models. The program burn model does not resolve the fine scale of the reaction zone; instead the goal is to solve for the hydrodynamics of the inert product gases on a coarse grid scale. which is insufficient to resolve the physical reaction zone. We first show that traditional program burn algorithms for detonation hydrocodes used for explosive design are inconsistent and yield incorrect shock dynamic behavior. To overcome these inconsistencies. we discuss a new class of program burn models based on detonation shock dynamic theory. This new class yields more consistent and robust algorithms that better reflect the correct shock dynamic behavior. (C) 2001 Elsevier Science. C1 Los Alamos Natl Lab, DX Div, Los Alamos, NM 87545 USA. Univ Illinois, Ctr Simulat Adv Rockets, Urbana, IL 61801 USA. RP Los Alamos Natl Lab, DX Div, POB 1663, Los Alamos, NM 87545 USA. EM jbb@lanl.gov; dss@uiuc.edu NR 14 TC 11 Z9 12 U1 1 U2 2 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0021-9991 EI 1090-2716 J9 J COMPUT PHYS JI J. Comput. Phys. PD DEC 10 PY 2001 VL 174 IS 2 BP 870 EP 902 DI 10.1006/jcph.2001.6942 PG 33 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA 508KV UT WOS:000173088000014 ER PT J AU Van der Woerd, J Xu, XW Li, HB Tapponnier, P Meyer, B Ryerson, FJ Meriaux, AS Xu, ZQ AF Van der Woerd, J Xu, XW Li, HB Tapponnier, P Meyer, B Ryerson, FJ Meriaux, AS Xu, ZQ TI Rapid active thrusting along the northwestern range front of the Tanghe Nan Shan (western Gansu, China) SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH LA English DT Article ID ALTYN-TAGH FAULT; TIBETAN PLATEAU; HAIYUAN FAULT; QILIAN-SHAN; C-14 DATA; SLIP; EARTHQUAKES; GROWTH; TECTONICS; ROTATION AB The western part of the Tanghe Nan Shan range southwest of Subei (western Gansu, China) is presently growing on thrust ramps splaying from the left-lateral Altyn Tagh Fault. Late Cenozoic thrusting has folded and sliced Oligocene-Miocence red beds into an imbricate wedge, capped by warped and uplifted Quaternary terraces that form a 2- to 5-km-wide ledge, north of the steeply faceted range front. Seismic scarps 1.5 to 4.5 m high cut young fans along the outer thrusts. Carbon 14 dating of organic remains collected on strath terraces constrains the chronology of deposition and incision by the streams. Most of the fans and terraces in the southern part of the Subei basin appear to have been emplaced after the last glacial maximum, particularly during the early Holocene optimum (9-5 ka). Measurements of the shapes of the warped terraces constrain minimum and maximum throws on the outer thrusts, The minimum vertical throw of 34 +/- 2 in of a surface dated at 8411 +/- 530 years B.P. at one site provides a minimum vertical uplift rate of 4.1 +/- 0.5 mm/yr. The maximum possible uplift (115 +/- 15 m) of the oldest terrace surface, whose probable age is 15 to 18, ka, places an upper bound on the uplift rate of 7 +/- 2 mm/yr. The thrust geometry at depth and the cumulative shortening (10-20 km) deduced from balancing sections logged across the imbricate thrust wedge are consistent with a shortening rate of about 5 mm/yr and an onset of thrusting at about 4 +/- 2 Ma. Such a shortening rate implies a significant northward decrease in slip rate along the Altyn Tagh Fault. The recent growth of the western Qilian mountain ranges thus appears to be intimately coupled with sinistral motion on the Altyn Tagh Fault and the extrusion of Tibet. C1 Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Inst Phys Globe, CNRS UMR 7578, F-75252 Paris 05, France. Minist Land & Resources, Inst Geol, Beijing 100037, Peoples R China. China Seismol Bur, Beijing 100029, Peoples R China. RP Van der Woerd, J (reprint author), Lawrence Livermore Natl Lab, POB 808,L202, Livermore, CA 94551 USA. EM vanderwoerd2@llnl.gov; xxi-wei@public3.bta.net.cn; tappon@ipgp.jussieu.fr; meyer@ipgp.jussieu.fr; ryerson1@llnl.gov; ameriaux@ipgp.jussieu.fr RI Meriaux, Anne-Sophie/G-1754-2010; Meyer, Bertrand/E-6903-2011; Tapponnier, .Paul/B-7033-2011 OI Tapponnier, .Paul/0000-0002-7135-1962 NR 32 TC 66 Z9 66 U1 2 U2 13 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-9313 EI 2169-9356 J9 J GEOPHYS RES-SOL EA JI J. Geophys. Res.-Solid Earth PD DEC 10 PY 2001 VL 106 IS B12 BP 30475 EP 30504 DI 10.1029/2001JB000583 PG 30 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 512JG UT WOS:000173320800003 ER PT J AU Williams, GP AF Williams, GP TI IR investigations of surfaces and adsorbates SO JOURNAL OF PHYSICS-CONDENSED MATTER LA English DT Article ID INFRARED SYNCHROTRON-RADIATION; HYDROGEN DIFFUSION; METAL-SURFACE; SPECTROSCOPY; CU(111); CU(100); OXYGEN; CO; REFLECTANCE; RESISTIVITY AB Synchrotron infrared reflection-absorption measurements on single crystal metal surfaces with adsorbates have led to the determination of many key parameters related to the bonding vibrational modes and the dynamics of adsorbates. In particular, energy couplings between electrons and adsorbate motion have been shown to be a dominant mechanism on metal surfaces. Excellent agreement has been obtained with calculations for many of the observations, and the synergy between theory and experiment has led to a deeper understanding of the roles of electrons and phonons in determining the properties of interfaces and their roles in phenomena as diverse as friction, lubrication, catalysis and adhesion. Nonetheless, as the experiments axe pushed harder, to describe such effects as co-adsorbed systems, disagreements continue to challenge the theory and our comprehension also is still evolving. C1 Thomas Jefferson Natl Accelerator Facil, Newport News, VA 23606 USA. RP Williams, GP (reprint author), Thomas Jefferson Natl Accelerator Facil, 12000 Jefferson Ave, Newport News, VA 23606 USA. NR 40 TC 7 Z9 7 U1 1 U2 6 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 10 PY 2001 VL 13 IS 49 BP 11367 EP 11390 DI 10.1088/0953-8984/13/49/315 PG 24 WC Physics, Condensed Matter SC Physics GA 505PL UT WOS:000172921100016 ER PT J AU Korobkov, I Gambarotta, S Yap, GPA Thompson, L Hay, PJ AF Korobkov, I Gambarotta, S Yap, GPA Thompson, L Hay, PJ TI Dinuclear trivalent and mixed-valence uranium [(-CH2-)(5)](4)-calix[4]tetrapyrrole complexes with short intermetallic distances SO ORGANOMETALLICS LA English DT Article ID CARBON BOND FORMATION; RAY CRYSTAL-STRUCTURE; EFFECTIVE CORE POTENTIALS; STRUCTURAL-CHARACTERIZATION; DINITROGEN COMPLEXES; OXIDATIVE-ADDITION; THIOLATE COMPLEXES; REACTIVITY; CHEMISTRY; ORGANOLANTHANIDE AB A dinuclear trivalent uranium complex (1) and a mixed-valence U(III)U(IV) complex (2) have been prepared by using the [(-CH2-)(5)](4)-calix[4]tetrapyrrole tetraanion. Both compounds display unusually short U-U distances with two metals held together by the bridging tetraanion, where each pyrrole ring adopts the eta (1):eta (5) bonding mode. Both magnetic measurements at variable temperature and DFT calculations carried out on the trivalent 1 indicate the existence of antiferromagnetic coupling between the two metal centers as the only significant U-U interaction. C1 Univ Ottawa, Dept Chem, Ottawa, ON K1N 6N5, Canada. Mem Univ Newfoundland, Dept Chem, St John, NF A1B 3X7, Canada. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Gambarotta, S (reprint author), Univ Ottawa, Dept Chem, Ottawa, ON K1N 6N5, Canada. NR 80 TC 29 Z9 29 U1 0 U2 5 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0276-7333 J9 ORGANOMETALLICS JI Organometallics PD DEC 10 PY 2001 VL 20 IS 25 BP 5440 EP 5445 DI 10.1021/om010510h PG 6 WC Chemistry, Inorganic & Nuclear; Chemistry, Organic SC Chemistry GA 500AD UT WOS:000172602700025 ER PT J AU Affolder, T Akimoto, H Akopian, A Albrow, MG Amaral, P Amidei, D Anikeev, K Antos, J Apollinari, G Arisawa, T Artikov, A Asakawa, T Ashmanskas, W Azfar, F Azzi-Bacchetta, P Bacchetta, N Bachacou, H Bailey, S de Barbaro, P Barbaro-Galtieri, A Barnes, VE Barnett, BA Baroiant, S Barone, M Bauer, G Bedeschi, F Belforte, S Bell, WH Bellettini, G Bellinger, J Benjamin, D Bensinger, J Beretvas, A Berge, JP Berryhill, J Bhatti, A Binkley, M Bisello, D Bishai, M Blair, RE Blocker, C Bloom, K Blumenfeld, B Blusk, SR Bocci, A Bodek, A Bokhari, W Bolla, G Bonushkin, Y Borras, K Bortoletto, D Boudreau, J Brandl, A van den Brink, S Bromberg, C Brozovic, M Brubaker, E Bruner, N Buckley-Geer, E Budagov, J Budd, HS Burkett, K Busetto, G Byon-Wagner, A Byrum, KL Cabrera, S Calafiura, R Campbell, M Carithers, W Carlson, J Carlsmith, D Caskey, W Castro, A Cauz, D Cerri, A Chan, AW Chang, PS Chang, PT Chapman, J Chen, C Chen, YC Cheng, MT Chertok, M Chiarelli, G Chirikov-Zorin, I Chlachidze, G Chlebana, F Christofek, L Chu, ML Chung, YS Ciobaru, CI Clark, AG Connolly, A Convery, ME Conway, J Cordelli, M Cranshaw, J Cropp, R Culbertson, R Dagenhart, D D'Auria, S DeJongh, F Dell'Agnello, S Dell'Orso, M Demortier, L Deninno, M Derwent, PF Devlin, T Dittmann, JR Dominguez, A Donati, S Done, J D'Onofrio, M Dorigo, T Eddy, N Einsweiler, K Elias, JE Engels, E Erbacher, R Errede, D Errede, S Fan, Q Feild, RG Fernandez, JP Ferretti, C Field, RD Fiori, I Flaugher, B Foster, GW Franklin, M Freeman, J Friedman, J Fukui, Y Furic, I Galeotti, S Gallas, A Gallinaro, M Gao, T Garcia-Sciveres, M Garfinkel, AR Gatti, P Gay, C Gerdes, DW Giannetti, P Glagolev, V Glenzinski, D Gold, M Goldstein, J Gorelov, I Goshaw, AT Gotra, Y Goulianos, K Green, C Grim, G Gris, P Groer, L Grosso-Pilcher, C Guenther, M Guillian, G da Costa, JG Haas, RM Haber, C Hahn, SR Hall, C Handa, T Handler, R Hao, W Happacher, F Hara, K Hardman, AD Harris, RM Hartmann, F Hatakeyama, K Hauser, J Heinrich, J Heiss, A Herndon, M Hill, C Hoffman, KD Holck, C Hollebeek, R Holloway, L Hughes, R Huston, J Huth, J Ikeda, H Incandela, J Introzzi, G Iwai, J Iwata, Y James, E Jones, M Joshi, U Kambara, H Kamon, T Kaneko, T Karr, K Kasha, H Kato, Y Keaffaber, TA Kelley, K Kelly, M Kennedy, RD Kepham, R Khazins, D Kikuchi, T Kilminster, B Kim, BJ Kim, DH Kim, HS Kim, MJ Kim, SB Kim, SH Kim, YK Kirby, M Kirk, M Kirsch, L Klimenko, S Koehn, P Kondo, K Konigsberg, J Korn, A Korytov, A Kovacs, E Kroll, J Kruse, M Kuhlmann, SE Kurino, K Kuwabara, T Laasanen, AT Lai, N Lami, S Lammel, S Lancaster, J Lancaster, M Lander, R Lath, A Latino, G LeCompte, T Lee, AM Lee, K Leone, S Lewis, JD Lindgren, M Liss, TM Liu, JB Liu, YC Litvintsev, DO Lobban, O Lockyer, N Loken, J Loreti, M Lucchesi, D Lukens, P Lusin, S Lyons, L Lys, J Madrak, R Maeshima, K Maksimovic, P Malferrari, L Mangano, M Mariotti, M Martignon, G Martin, A Matthews, JAJ Mayer, J Mazzanti, P McFarland, KS McIntyre, P McKigney, E Menguzzato, M Menzione, A Mesropian, C Meyer, A Miao, T Miller, R Miller, JS Minato, H Miscetti, S Mishina, M Mitselmakher, G Moggi, N Moore, E Moore, R Morita, Y Moulik, T Mulhearn, M Mukherjee, A Muller, T Munar, A Murat, P Murgia, S Nachtman, J Nagaslaev, V Nahn, S Nakada, H Nakano, I Nelson, C Nelson, T Neu, C Neuberger, D Newman-Holmes, C Ngan, CYP Niu, H Nodulman, L Nomerotski, A Oh, SH Oh, YD Ohmoto, T Ohsugi, T Oishi, R Okusawa, T Olsen, J Orejudos, W Pagliarone, C Palmonari, F Paoletti, R Papadimitriou, V Partos, D Patrick, J Pauletta, G Paulini, M Paus, C Pellett, D Pescara, L Phillips, TJ Piacentino, G Pitts, KT Pompos, A Pondrom, L Pope, G Popovic, M Prokoshin, F Proudfoot, J Ptohos, F Pukhov, O Punzi, G Rakitine, A Ratnikov, F Reher, D Reichold, A Ribon, A Riegler, W Rimondi, F Ristori, L Riveline, M Robertson, WJ Robinson, A Rodrigo, T Rolli, S Rosenson, L Roser, R Rossin, R Roy, A Ruiz, A Safonov, A St Denis, R Sakumoto, WK Saltzberg, D Sanchez, C Sansoni, A Santi, L Sato, H Savard, P Schlabach, P Schmidt, EE Schmidt, MP Schmitt, M Scodellaro, L Scott, A Scribano, A Segler, S Seidel, S Seiya, Y Semenov, A Semeria, F Shah, T Shapiro, MD Shepard, PF Shibayama, T Shimojima, M Shochet, M Sidoti, A Siegrist, J Sill, A Sinervo, P Singh, P Slaughter, AJ Sliwa, K Smith, C Snider, FD Solodsky, A Spalding, J Speer, T Sphicas, R Spinella, F Spiropulu, M Spiegel, L Steele, J Stefanini, A Strologas, J Strumia, F Stuart, D Sumorok, K Suzuki, T Takano, T Takashima, R Takikawa, K Tamburello, P Tanaka, M Tannenbaum, B Tecchio, M Tesarek, R Teng, PK Terashi, K Tether, S Thompson, AS Thurman-Keup, R Tipton, R Tkaczyk, S Toback, D Tollefson, K Tollestrup, A Tonelli, D Toyoda, H Trischuk, W de Troconiz, JF Tseng, J Turini, N Ukegawa, F Vaiciulis, T Valls, J Vejcik, S Velev, G Veramendi, G Vidal, R Vila, I Vilar, R Volobouev, I von der Mey, M Vucinic, D Wagner, RG Wagner, RL Wallace, NB Wan, Z Wang, C Wang, MJ Ward, B Waschke, S Watanabe, T Waters, D Watts, T Webb, R Wenzel, H Wester, WC Wicklund, AB Wicklund, E Wilkes, T Williams, HH Wilson, P Winer, BL Winn, D Wolbers, S Wolinski, D Wolinski, J Wolinski, S Worm, S Wu, X Wyss, J Yao, W Yeh, GP Yeh, P Yoh, J Yosef, C Yoshida, T Yu, I Yu, S Yu, Z Zanetti, A Zetti, F Zucchelli, S AF Affolder, T Akimoto, H Akopian, A Albrow, MG Amaral, P Amidei, D Anikeev, K Antos, J Apollinari, G Arisawa, T Artikov, A Asakawa, T Ashmanskas, W Azfar, F Azzi-Bacchetta, P Bacchetta, N Bachacou, H Bailey, S de Barbaro, P Barbaro-Galtieri, A Barnes, VE Barnett, BA Baroiant, S Barone, M Bauer, G Bedeschi, F Belforte, S Bell, WH Bellettini, G Bellinger, J Benjamin, D Bensinger, J Beretvas, A Berge, JP Berryhill, J Bhatti, A Binkley, M Bisello, D Bishai, M Blair, RE Blocker, C Bloom, K Blumenfeld, B Blusk, SR Bocci, A Bodek, A Bokhari, W Bolla, G Bonushkin, Y Borras, K Bortoletto, D Boudreau, J Brandl, A van den Brink, S Bromberg, C Brozovic, M Brubaker, E Bruner, N Buckley-Geer, E Budagov, J Budd, HS Burkett, K Busetto, G Byon-Wagner, A Byrum, KL Cabrera, S Calafiura, R Campbell, M Carithers, W Carlson, J Carlsmith, D Caskey, W Castro, A Cauz, D Cerri, A Chan, AW Chang, PS Chang, PT Chapman, J Chen, C Chen, YC Cheng, MT Chertok, M Chiarelli, G Chirikov-Zorin, I Chlachidze, G Chlebana, F Christofek, L Chu, ML Chung, YS Ciobaru, CI Clark, AG Connolly, A Convery, ME Conway, J Cordelli, M Cranshaw, J Cropp, R Culbertson, R Dagenhart, D D'Auria, S DeJongh, F Dell'Agnello, S Dell'Orso, M Demortier, L Deninno, M Derwent, PF Devlin, T Dittmann, JR Dominguez, A Donati, S Done, J D'Onofrio, M Dorigo, T Eddy, N Einsweiler, K Elias, JE Engels, E Erbacher, R Errede, D Errede, S Fan, Q Feild, RG Fernandez, JP Ferretti, C Field, RD Fiori, I Flaugher, B Foster, GW Franklin, M Freeman, J Friedman, J Fukui, Y Furic, I Galeotti, S Gallas, A Gallinaro, M Gao, T Garcia-Sciveres, M Garfinkel, AR Gatti, P Gay, C Gerdes, DW Giannetti, P Glagolev, V Glenzinski, D Gold, M Goldstein, J Gorelov, I Goshaw, AT Gotra, Y Goulianos, K Green, C Grim, G Gris, P Groer, L Grosso-Pilcher, C Guenther, M Guillian, G da Costa, JG Haas, RM Haber, C Hahn, SR Hall, C Handa, T Handler, R Hao, W Happacher, F Hara, K Hardman, AD Harris, RM Hartmann, F Hatakeyama, K Hauser, J Heinrich, J Heiss, A Herndon, M Hill, C Hoffman, KD Holck, C Hollebeek, R Holloway, L Hughes, R Huston, J Huth, J Ikeda, H Incandela, J Introzzi, G Iwai, J Iwata, Y James, E Jones, M Joshi, U Kambara, H Kamon, T Kaneko, T Karr, K Kasha, H Kato, Y Keaffaber, TA Kelley, K Kelly, M Kennedy, RD Kepham, R Khazins, D Kikuchi, T Kilminster, B Kim, BJ Kim, DH Kim, HS Kim, MJ Kim, SB Kim, SH Kim, YK Kirby, M Kirk, M Kirsch, L Klimenko, S Koehn, P Kondo, K Konigsberg, J Korn, A Korytov, A Kovacs, E Kroll, J Kruse, M Kuhlmann, SE Kurino, K Kuwabara, T Laasanen, AT Lai, N Lami, S Lammel, S Lancaster, J Lancaster, M Lander, R Lath, A Latino, G LeCompte, T Lee, AM Lee, K Leone, S Lewis, JD Lindgren, M Liss, TM Liu, JB Liu, YC Litvintsev, DO Lobban, O Lockyer, N Loken, J Loreti, M Lucchesi, D Lukens, P Lusin, S Lyons, L Lys, J Madrak, R Maeshima, K Maksimovic, P Malferrari, L Mangano, M Mariotti, M Martignon, G Martin, A Matthews, JAJ Mayer, J Mazzanti, P McFarland, KS McIntyre, P McKigney, E Menguzzato, M Menzione, A Mesropian, C Meyer, A Miao, T Miller, R Miller, JS Minato, H Miscetti, S Mishina, M Mitselmakher, G Moggi, N Moore, E Moore, R Morita, Y Moulik, T Mulhearn, M Mukherjee, A Muller, T Munar, A Murat, P Murgia, S Nachtman, J Nagaslaev, V Nahn, S Nakada, H Nakano, I Nelson, C Nelson, T Neu, C Neuberger, D Newman-Holmes, C Ngan, CYP Niu, H Nodulman, L Nomerotski, A Oh, SH Oh, YD Ohmoto, T Ohsugi, T Oishi, R Okusawa, T Olsen, J Orejudos, W Pagliarone, C Palmonari, F Paoletti, R Papadimitriou, V Partos, D Patrick, J Pauletta, G Paulini, M Paus, C Pellett, D Pescara, L Phillips, TJ Piacentino, G Pitts, KT Pompos, A Pondrom, L Pope, G Popovic, M Prokoshin, F Proudfoot, J Ptohos, F Pukhov, O Punzi, G Rakitine, A Ratnikov, F Reher, D Reichold, A Ribon, A Riegler, W Rimondi, F Ristori, L Riveline, M Robertson, WJ Robinson, A Rodrigo, T Rolli, S Rosenson, L Roser, R Rossin, R Roy, A Ruiz, A Safonov, A St Denis, R Sakumoto, WK Saltzberg, D Sanchez, C Sansoni, A Santi, L Sato, H Savard, P Schlabach, P Schmidt, EE Schmidt, MP Schmitt, M Scodellaro, L Scott, A Scribano, A Segler, S Seidel, S Seiya, Y Semenov, A Semeria, F Shah, T Shapiro, MD Shepard, PF Shibayama, T Shimojima, M Shochet, M Sidoti, A Siegrist, J Sill, A Sinervo, P Singh, P Slaughter, AJ Sliwa, K Smith, C Snider, FD Solodsky, A Spalding, J Speer, T Sphicas, R Spinella, F Spiropulu, M Spiegel, L Steele, J Stefanini, A Strologas, J Strumia, F Stuart, D Sumorok, K Suzuki, T Takano, T Takashima, R Takikawa, K Tamburello, P Tanaka, M Tannenbaum, B Tecchio, M Tesarek, R Teng, PK Terashi, K Tether, S Thompson, AS Thurman-Keup, R Tipton, R Tkaczyk, S Toback, D Tollefson, K Tollestrup, A Tonelli, D Toyoda, H Trischuk, W de Troconiz, JF Tseng, J Turini, N Ukegawa, F Vaiciulis, T Valls, J Vejcik, S Velev, G Veramendi, G Vidal, R Vila, I Vilar, R Volobouev, I von der Mey, M Vucinic, D Wagner, RG Wagner, RL Wallace, NB Wan, Z Wang, C Wang, MJ Ward, B Waschke, S Watanabe, T Waters, D Watts, T Webb, R Wenzel, H Wester, WC Wicklund, AB Wicklund, E Wilkes, T Williams, HH Wilson, P Winer, BL Winn, D Wolbers, S Wolinski, D Wolinski, J Wolinski, S Worm, S Wu, X Wyss, J Yao, W Yeh, GP Yeh, P Yoh, J Yosef, C Yoshida, T Yu, I Yu, S Yu, Z Zanetti, A Zetti, F Zucchelli, S CA CDF Collaboration TI Observation of diffractive J/psi production at the Fermilab Tevatron SO PHYSICAL REVIEW LETTERS LA English DT Article ID SILICON VERTEX DETECTOR; DIJET PRODUCTION; CDF AB We report the first observation of diffractive J/psi(--> mu (+)mu (-)) production in <(p)power bar> collisions at roots = 1.8 TeV. Diffractive events are identified by their rapidity gap signature. In a sample of events with two muons of transverse momentum p(T)(mu) > 2 GeV/c within the pseudorapidity region \ eta \ < 1.0, the ratio of diffractive to total J/ production rates is found to be R-J/psi = [1.45 +/- 0.25]%. ne ratio R-J/psi(X) is presented as a function of x-Bjorken. By combining it with our previously measured corresponding ratio R-jj(x) for diffractive dijet production, we extract a value of 0.59 +/- 0.15 for the gluon fraction of the diffractive structure function of the proton. C1 Ernest Orlando Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. Acad Sinica, Inst Phys, Taipei 11529, Taiwan. 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 Davis, Davis, CA 95616 USA. Univ Calif Los Angeles, Los Angeles, CA 90024 USA. Univ Cantabria, Inst Fis Cantabria, CSIC, E-39005 Santander, Spain. Univ Chicago, Enrico Fermi Inst, Chicago, IL 60637 USA. Joint Inst Nucl Res, RU-141980 Dubna, Russia. 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. Univ Glasgow, Glasgow G12 8QQ, Lanark, Scotland. Harvard Univ, Cambridge, MA 02138 USA. Hiroshima Univ, Higashihiroshima 724, Japan. Univ Illinois, Urbana, IL 61801 USA. Johns Hopkins Univ, Baltimore, MD 21218 USA. Univ Karlsruhe, Inst Expt Kernphys, D-76128 Karlsruhe, Germany. Kyungpook Natl Univ, Ctr High Energy Phys, Taegu 702701, South Korea. Seoul Natl Univ, Seoul 151742, South Korea. Sungkyunkwan Univ, Suwon 440746, South Korea. High Energy Accelerator Res Org KEK, Tsukuba, Ibaraki 305, Japan. 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 Oxford, Oxford OX1 3RH, England. 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. Texas A&M Univ, College Stn, TX 77843 USA. Texas Tech Univ, Lubbock, TX 79409 USA. Univ Toronto, Inst Particle Phys, Toronto, ON M5S 1A7, Canada. Univ Trieste, Ist Nazl Fis Nucl, Udine, Italy. Univ Tsukuba, Tsukuba, Ibaraki 305, 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 Affolder, T (reprint author), Ernest Orlando Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RI Prokoshin, Fedor/E-2795-2012; Introzzi, Gianluca/K-2497-2015; Gorelov, Igor/J-9010-2015; Cabrera Urban, Susana/H-1376-2015; Lancaster, Mark/C-1693-2008; Vucinic, Dejan/C-2406-2008; Nomerotski, Andrei/A-5169-2010; Ruiz, Alberto/E-4473-2011; St.Denis, Richard/C-8997-2012; Azzi, Patrizia/H-5404-2012; Punzi, Giovanni/J-4947-2012; Chiarelli, Giorgio/E-8953-2012; Kim, Soo-Bong/B-7061-2014; Gallas Torreira, Abraham Antonio/K-6508-2014; Scodellaro, Luca/K-9091-2014; Paulini, Manfred/N-7794-2014 OI Prokoshin, Fedor/0000-0001-6389-5399; Introzzi, Gianluca/0000-0002-1314-2580; Gorelov, Igor/0000-0001-5570-0133; Ruiz, Alberto/0000-0002-3639-0368; Azzi, Patrizia/0000-0002-3129-828X; Punzi, Giovanni/0000-0002-8346-9052; Chiarelli, Giorgio/0000-0001-9851-4816; Gallas Torreira, Abraham Antonio/0000-0002-2745-7954; Scodellaro, Luca/0000-0002-4974-8330; Paulini, Manfred/0000-0002-6714-5787 NR 12 TC 28 Z9 28 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 10 PY 2001 VL 87 IS 24 AR 241802 DI 10.1103/PhysRevLett.87.241802 PG 6 WC Physics, Multidisciplinary SC Physics GA 500TD UT WOS:000172642100009 ER PT J AU Aubert, B Boutigny, D Gaillard, JM Hicheur, A Karyotakis, Y Lees, JP Robbe, P Tisserand, V Palano, A Chen, GP Chen, JC Qi, ND Rong, G Wang, P Zhu, YS Eigen, G Reinertsen, PL Stugu, B Abbott, B Abrams, GS Borgland, AW Breon, AB Brown, DN Button-Shafer, J Cahn, RN Clark, AR Gill, MS Gritsan, A Groysman, Y Jacobsen, RG Kadel, RW Kadyk, J Kerth, LT Kluth, S Kolomensky, YG Kral, JR LeClerc, C Levi, ME Liu, T Lynch, G Meyer, AB Momayezi, M Oddone, PJ Perazzo, A Pripstein, M Roe, NA Romosan, A Ronan, MT Shelkov, VG Telnov, AV Wenzel, WA Bright-Thomas, PG Harrison, TJ Hawkes, CM Kirk, A Knowles, DJ O'Neale, SW Penny, RC Watson, AT Watson, NK Deppermann, T Goetzen, K Koch, H Krug, J Kunze, M Lewandowski, B Peters, K Schmuecker, H Steinke, M Andress, JC Barlow, NR Bhimji, W Chevalier, N Clark, PJ Cottingham, WN De Groot, N Dyce, N Foster, B McFall, JD Wallom, D Wilson, FF Abe, K Hearty, C Mattison, TS McKenna, JA Thiessen, D Jolly, S McKemey, AK Tinslay, J Blinov, VE Ukin, ADB Bukin, DA Buzykaev, AR Golubev, VB Ivanchenko, VN Korol, AA Kravchenko, EA Onuchin, AR Salnikov, AA Serednyakov, SI Skovpen, YI Telnov, VI Yushkov, AN Best, D Lankford, AJ Mandelkern, M McMahon, S Stoker, DR Ahsan, A Arisaka, K Buchanan, C Chun, S Branson, JG MacFarlane, DB Prell, S Rahatlou, S Raven, G Sharma, V Campagnari, C Dahmes, B Hart, PA Kuznetsova, N Levy, SL Long, O Lu, A Richman, JD Verkerke, W Witherell, M Yellin, S Beringer, J Dorfan, DE Eisner, AM Frey, A Grillo, AA Grothe, M Heusch, CA Johnson, RP Kroeger, W Lockman, WS Pulliam, T Sadrozinski, H Schalk, T Schmitz, RE Schumm, BA Seiden, A Turri, M Walkowiak, W Williams, DC Wilson, MG Chen, E Dubois-Felsmann, GR Dvoretskii, A Hitlin, DG Metzler, S Oyang, J Porter, FC Ryd, A Samuel, A Weaver, M Yang, S Zhu, RY Devmal, S Geld, TL Jayatilleke, S Mancinelli, G Meadows, BT Sokoloff, MD Barillari, T Bloom, P Dima, MO Fahey, S Ford, WT Johnson, DR Nauenberg, U Olivas, A Park, H Rankin, P Roy, J Sen, S Smith, JG van Hoek, WC Wagner, DL Blouw, J Harton, JL Krishnamurthy, M Soffer, A Toki, WH Wilson, RJ Zhang, J Brandt, T Brose, J Colberg, T Dahlinger, G Dickopp, M Dubitzky, RS Maly, E Muller-Pfefferkorn, R Otto, S Schubert, KR Schwierz, R Spaan, B Wilden, L Behr, L Bernard, D Bonneaud, GR Brochard, F Cohen-Tanugi, J Ferrag, S Roussot, E T'Jampens, S Thiebaux, C Vasileiadis, G Verderi, M Anjomshoaa, A Bernet, R Khan, A Muheim, F Playfer, S Swain, JE Falbo, M Borean, C Bozzi, C Dittongo, S Folegani, M Piemontese, L Treadwell, E Anulli, F Baidini-Ferroli, R Calcaterra, A de Sangro, R Falciai, D Finocchiaro, G Patteri, P Peruzzi, IM Piccolo, M Xie, Y Zallo, A Bagnasco, S Buzzo, A Contri, R Crosetti, G Fabbricatore, P Farinon, S LoVetere, M Macri, M Monge, MR Musenich, R Pallavicini, M Parodi, R Passaggio, S Pastore, FC Patrignani, C Pia, MG Priano, C Robutti, E Santroni, A Morii, M Bartoldus, R Dignan, T Hamilton, R Mallick, U Cochran, J Crawley, HB Fischer, PA Lamsa, J Meyer, WT Rosenberg, EI Benkebil, M Grosdidier, G Hast, C Hocker, A Lacker, HM LePeltier, V Lutz, AM Plaszczynski, S Schune, MH Trincaz-Duvoid, S Valassi, A Wormser, G Bionta, RM Brigljevic, V Lange, DJ Mugge, M Shi, X van Bibber, K Wenaus, TJ Wright, DM Wuest, CR Carroll, M Fry, JR Gabathuler, E Gamet, R George, M Kay, M Payne, DJ Sloane, RJ Touramanis, C Aspinwall, ML Bowerman, DA Dauncey, PD Egede, U Eschrich, I Gunawardane, NJW Nash, JA Sanders, P Smith, D Azzopardi, DE Back, JJ Dixon, P Harrison, PF Potter, RJL Shorthouse, HW Strother, P Vidal, PB Williams, MI Cowan, G George, S Green, MG Kurup, A Marker, CE McGrath, P McMahon, TR Ricciardi, S Salvatore, R Scott, I Vaitsas, G Brown, D Davis, CL Allison, J Barlow, RJ Boyd, JT Forti, AC Fullwood, J Jackson, F Lafferty, GD Savvas, N Simopoulos, ET Weatherall, JH Farbin, A Jawahery, A Lillard, V Olsen, J Roberts, DA Schieck, JR Blaylock, G Dallapiccola, C Flood, KT Hertzbach, SS Kofler, R Moore, TB Staengle, H Willocq, S Brau, B Cowan, R Sciolla, G Taylor, F Yamamoto, RK Milek, M Patel, PM Trischuk, J Lanni, F Palombo, F Bauer, JM Booke, M Cremaldi, L Eschenburg, V Kroeger, R Reidy, J Sanders, DA Summers, DJ Martin, JP Nief, JY Seitz, R Taras, P Zacek, V Nicholson, H Sutton, CS Cartaro, C Cavallo, N De Nardo, G Fabozzi, F Gatto, C Lista, L Paolucci, P Piccolo, D Sciacca, C LoSecca, JM Alsmiller, JRG Gabriel, TA Handler, T Brau, J Frey, R Iwasaki, M Sinev, NB Strom, D Colecchia, F Dal Corso, F Dorigo, A Galeazzi, F Margoni, M Michelon, G Morandin, M Posocco, M Rotondo, M Simonetto, F Stroili, R Torassa, E Voci, C Benayoun, M Briand, H Chauveau, J David, R De la Vaissiere, C Del Buono, L Hamon, O Le Diberder, F Leruste, P Lory, J Roos, L Stark, J Versille, S Manfredi, PF Re, V Speziali, V Frank, ED Gladney, L Guo, QH Panetta, JH Angelini, C Batignani, G Bettarini, S Bondioli, M Carpinelli, M Forti, F Giorgi, MA Lusiani, A Martinez-Vidal, F Morganti, M Neri, N Paoloni, E Rama, M Rizzo, G Sandrelli, F Simi, G Triggiani, G Walsh, J Haire, M Judd, D Paick, K Turnbull, L Wagoner, DE Albert, J Bula, C Elmer, P Lu, C McDonald, KT Miftakov, V Schaffner, SF Smith, AJS Tumanov, A Varnes, EW Cavoto, G del Re, D Faccini, R Ferrarotto, F Ferroni, F Fratini, K Lamanna, E Leonardi, E Mazzoni, MA Morganti, S Piredda, G Tehrani, FS Serra, M Voena, C Christ, S Waldi, R Adye, T Franek, B Geddes, NI Gopal, GP Xella, SM Aleksan, R De Domenico, G Emery, S Gaidot, A Ganzhur, SF Giraud, PF de Monchenault, GH Kozanecki, W Langer, M London, GW Mayer, B Serfass, B Vasseur, G Yeche, C Zito, M Copty, N Purohit, MV Singh, H Yumiceva, FX Adam, I Anthony, RL Aston, D Baird, K Bloom, E Boyarski, AM Bulos, F Calderini, G Claus, R Convery, MR Coupal, DP Coward, DH Dorfan, J Doser, M Dunwoodie, W Field, RC Glanzman, T Godfrey, GL Gowdy, SJ Grosso, R Himel, T Huffer, ME Innes, WR Jessop, CP Kelsey, MH Kim, P Kocian, ML Langenegger, U Leith, DWGS Luitz, S Luth, V Lynch, HL Marsiske, H Menke, S Messner, R Moffeit, KC Mount, R Muller, DR O'Grady, CP Perl, M Petrak, S Quinn, H Ratcliff, BN Robertson, SH Rochester, LS Roodman, A Schietinger, T Schindler, RH Schwiening, J Serbo, VV Snyder, A Soha, A Spanier, SM Stelzer, J Su, D Sullivan, MK Tanaka, HA Va'vra, J Wagner, SR Weinstein, AJR Wisniewski, WJ Wright, DH Young, CC Burchat, RR Cheng, CH Kirkby, D Meyer, TI Roat, C Henderson, R Bugg, W Cohn, H Weidemann, AW Izen, JM Kitayama, I Lou, XC Turcotte, M Bianchhi, F Bona, M Di Girolamo, B Gamba, D Smol, A Zanin, D Lanceri, L Pompili, A Vaugnin, G Panvini, RS Brown, CM De Silva, A Kowalewski, R Roney, JM Band, HR Charles, E Dasu, S Di Lodovico, F Eichenbaum, AM Hu, H Johnson, JR Liu, R Nielsen, J Pan, Y Prepost, R Scott, IJ Sekula, SJ von Wimmersperg-Toeller, JH Wu, SL Yu, Z Zobernig, H Kordich, TMB Neal, H AF Aubert, B Boutigny, D Gaillard, JM Hicheur, A Karyotakis, Y Lees, JP Robbe, P Tisserand, V Palano, A Chen, GP Chen, JC Qi, ND Rong, G Wang, P Zhu, YS Eigen, G Reinertsen, PL Stugu, B Abbott, B Abrams, GS Borgland, AW Breon, AB Brown, DN Button-Shafer, J Cahn, RN Clark, AR Gill, MS Gritsan, A Groysman, Y Jacobsen, RG Kadel, RW Kadyk, J Kerth, LT Kluth, S Kolomensky, YG Kral, JR LeClerc, C Levi, ME Liu, T Lynch, G Meyer, AB Momayezi, M Oddone, PJ Perazzo, A Pripstein, M Roe, NA Romosan, A Ronan, MT Shelkov, VG Telnov, AV Wenzel, WA Bright-Thomas, PG Harrison, TJ Hawkes, CM Kirk, A Knowles, DJ O'Neale, SW Penny, RC Watson, AT Watson, NK Deppermann, T Goetzen, K Koch, H Krug, J Kunze, M Lewandowski, B Peters, K Schmuecker, H Steinke, M Andress, JC Barlow, NR Bhimji, W Chevalier, N Clark, PJ Cottingham, WN De Groot, N Dyce, N Foster, B McFall, JD Wallom, D Wilson, FF Abe, K Hearty, C Mattison, TS McKenna, JA Thiessen, D Jolly, S McKemey, AK Tinslay, J Blinov, VE Ukin, ADB Bukin, DA Buzykaev, AR Golubev, VB Ivanchenko, VN Korol, AA Kravchenko, EA Onuchin, AR Salnikov, AA Serednyakov, SI Skovpen, YI Telnov, VI Yushkov, AN Best, D Lankford, AJ Mandelkern, M McMahon, S Stoker, DR Ahsan, A Arisaka, K Buchanan, C Chun, S Branson, JG MacFarlane, DB Prell, S Rahatlou, S Raven, G Sharma, V Campagnari, C Dahmes, B Hart, PA Kuznetsova, N Levy, SL Long, O Lu, A Richman, JD Verkerke, W Witherell, M Yellin, S Beringer, J Dorfan, DE Eisner, AM Frey, A Grillo, AA Grothe, M Heusch, CA Johnson, RP Kroeger, W Lockman, WS Pulliam, T Sadrozinski, H Schalk, T Schmitz, RE Schumm, BA Seiden, A Turri, M Walkowiak, W Williams, DC Wilson, MG Chen, E Dubois-Felsmann, GR Dvoretskii, A Hitlin, DG Metzler, S Oyang, J Porter, FC Ryd, A Samuel, A Weaver, M Yang, S Zhu, RY Devmal, S Geld, TL Jayatilleke, S Mancinelli, G Meadows, BT Sokoloff, MD Barillari, T Bloom, P Dima, MO Fahey, S Ford, WT Johnson, DR Nauenberg, U Olivas, A Park, H Rankin, P Roy, J Sen, S Smith, JG van Hoek, WC Wagner, DL Blouw, J Harton, JL Krishnamurthy, M Soffer, A Toki, WH Wilson, RJ Zhang, J Brandt, T Brose, J Colberg, T Dahlinger, G Dickopp, M Dubitzky, RS Maly, E Muller-Pfefferkorn, R Otto, S Schubert, KR Schwierz, R Spaan, B Wilden, L Behr, L Bernard, D Bonneaud, GR Brochard, F Cohen-Tanugi, J Ferrag, S Roussot, E T'Jampens, S Thiebaux, C Vasileiadis, G Verderi, M Anjomshoaa, A Bernet, R Khan, A Muheim, F Playfer, S Swain, JE Falbo, M Borean, C Bozzi, C Dittongo, S Folegani, M Piemontese, L Treadwell, E Anulli, F Baidini-Ferroli, R Calcaterra, A de Sangro, R Falciai, D Finocchiaro, G Patteri, P Peruzzi, IM Piccolo, M Xie, Y Zallo, A Bagnasco, S Buzzo, A Contri, R Crosetti, G Fabbricatore, P Farinon, S LoVetere, M Macri, M Monge, MR Musenich, R Pallavicini, M Parodi, R Passaggio, S Pastore, FC Patrignani, C Pia, MG Priano, C Robutti, E Santroni, A Morii, M Bartoldus, R Dignan, T Hamilton, R Mallick, U Cochran, J Crawley, HB Fischer, PA Lamsa, J Meyer, WT Rosenberg, EI Benkebil, M Grosdidier, G Hast, C Hocker, A Lacker, HM LePeltier, V Lutz, AM Plaszczynski, S Schune, MH Trincaz-Duvoid, S Valassi, A Wormser, G Bionta, RM Brigljevic, V Lange, DJ Mugge, M Shi, X van Bibber, K Wenaus, TJ Wright, DM Wuest, CR Carroll, M Fry, JR Gabathuler, E Gamet, R George, M Kay, M Payne, DJ Sloane, RJ Touramanis, C Aspinwall, ML Bowerman, DA Dauncey, PD Egede, U Eschrich, I Gunawardane, NJW Nash, JA Sanders, P Smith, D Azzopardi, DE Back, JJ Dixon, P Harrison, PF Potter, RJL Shorthouse, HW Strother, P Vidal, PB Williams, MI Cowan, G George, S Green, MG Kurup, A Marker, CE McGrath, P McMahon, TR Ricciardi, S Salvatore, R Scott, I Vaitsas, G Brown, D Davis, CL Allison, J Barlow, RJ Boyd, JT Forti, AC Fullwood, J Jackson, F Lafferty, GD Savvas, N Simopoulos, ET Weatherall, JH Farbin, A Jawahery, A Lillard, V Olsen, J Roberts, DA Schieck, JR Blaylock, G Dallapiccola, C Flood, KT Hertzbach, SS Kofler, R Moore, TB Staengle, H Willocq, S Brau, B Cowan, R Sciolla, G Taylor, F Yamamoto, RK Milek, M Patel, PM Trischuk, J Lanni, F Palombo, F Bauer, JM Booke, M Cremaldi, L Eschenburg, V Kroeger, R Reidy, J Sanders, DA Summers, DJ Martin, JP Nief, JY Seitz, R Taras, P Zacek, V Nicholson, H Sutton, CS Cartaro, C Cavallo, N De Nardo, G Fabozzi, F Gatto, C Lista, L Paolucci, P Piccolo, D Sciacca, C LoSecca, JM Alsmiller, JRG Gabriel, TA Handler, T Brau, J Frey, R Iwasaki, M Sinev, NB Strom, D Colecchia, F Dal Corso, F Dorigo, A Galeazzi, F Margoni, M Michelon, G Morandin, M Posocco, M Rotondo, M Simonetto, F Stroili, R Torassa, E Voci, C Benayoun, M Briand, H Chauveau, J David, R De la Vaissiere, C Del Buono, L Hamon, O Le Diberder, F Leruste, P Lory, J Roos, L Stark, J Versille, S Manfredi, PF Re, V Speziali, V Frank, ED Gladney, L Guo, QH Panetta, JH Angelini, C Batignani, G Bettarini, S Bondioli, M Carpinelli, M Forti, F Giorgi, MA Lusiani, A Martinez-Vidal, F Morganti, M Neri, N Paoloni, E Rama, M Rizzo, G Sandrelli, F Simi, G Triggiani, G Walsh, J Haire, M Judd, D Paick, K Turnbull, L Wagoner, DE Albert, J Bula, C Elmer, P Lu, C McDonald, KT Miftakov, V Schaffner, SF Smith, AJS Tumanov, A Varnes, EW Cavoto, G del Re, D Faccini, R Ferrarotto, F Ferroni, F Fratini, K Lamanna, E Leonardi, E Mazzoni, MA Morganti, S Piredda, G Tehrani, FS Serra, M Voena, C Christ, S Waldi, R Adye, T Franek, B Geddes, NI Gopal, GP Xella, SM Aleksan, R De Domenico, G Emery, S Gaidot, A Ganzhur, SF Giraud, PF de Monchenault, GH Kozanecki, W Langer, M London, GW Mayer, B Serfass, B Vasseur, G Yeche, C Zito, M Copty, N Purohit, MV Singh, H Yumiceva, FX Adam, I Anthony, RL Aston, D Baird, K Bloom, E Boyarski, AM Bulos, F Calderini, G Claus, R Convery, MR Coupal, DP Coward, DH Dorfan, J Doser, M Dunwoodie, W Field, RC Glanzman, T Godfrey, GL Gowdy, SJ Grosso, R Himel, T Huffer, ME Innes, WR Jessop, CP Kelsey, MH Kim, P Kocian, ML Langenegger, U Leith, DWGS Luitz, S Luth, V Lynch, HL Marsiske, H Menke, S Messner, R Moffeit, KC Mount, R Muller, DR O'Grady, CP Perl, M Petrak, S Quinn, H Ratcliff, BN Robertson, SH Rochester, LS Roodman, A Schietinger, T Schindler, RH Schwiening, J Serbo, VV Snyder, A Soha, A Spanier, SM Stelzer, J Su, D Sullivan, MK Tanaka, HA Va'vra, J Wagner, SR Weinstein, AJR Wisniewski, WJ Wright, DH Young, CC Burchat, RR Cheng, CH Kirkby, D Meyer, TI Roat, C Henderson, R Bugg, W Cohn, H Weidemann, AW Izen, JM Kitayama, I Lou, XC Turcotte, M Bianchhi, F Bona, M Di Girolamo, B Gamba, D Smol, A Zanin, D Lanceri, L Pompili, A Vaugnin, G Panvini, RS Brown, CM De Silva, A Kowalewski, R Roney, JM Band, HR Charles, E Dasu, S Di Lodovico, F Eichenbaum, AM Hu, H Johnson, JR Liu, R Nielsen, J Pan, Y Prepost, R Scott, IJ Sekula, SJ von Wimmersperg-Toeller, JH Wu, SL Yu, Z Zobernig, H Kordich, TMB Neal, H CA BABAR Collaboration TI Measurement of the B -> J/psi K*(892) decay amplitudes SO PHYSICAL REVIEW LETTERS LA English DT Article ID ASYMMETRIES AB We present a measurement of the decay amplitudes in B --> J/psiK*(892) channels using 20.7 fb(-1) of data collected at the Y(4S) resonance with the BABAR detector at PEP-H. We measure a P-wave fraction R-perpendicular to = (16.0 +/- 3.2 +/- 1.4)% and a longitudinal polarization fraction (59.7 +/- 2.8 +/- 2.4)%. The measurement of a relative phase that is neither 0 nor pi, phi (parallel to) = 2.50 +/- 0.20 +/- 0.08 radians, favors a departure from the factorization hypothesis. Although the decay B --> J/psiK pi proceeds mainly via K*(892), there is also evidence for K-2*(1430) and K pi S-wave contributions. C1 Phys Particules Lab, F-74941 Annecy Le Vieux, France. Univ Bari, Dipartmento Fis, I-70126 Bari, Italy. Ist Nazl Fis Nucl, I-70126 Bari, Italy. Inst High Energy Phys, Beijing 100039, Peoples R China. Univ Bergen, Inst Phys, N-5007 Bergen, Norway. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Birmingham, Birmingham B15 2TT, W Midlands, England. Ruhr Univ Bochum, Inst Expt Phys 1, D-44780 Bochum, Germany. Univ Bristol, Bristol BS8 1TL, Avon, England. Univ British Columbia, Vancouver, BC V6T 1Z1, Canada. Brunel Univ, Uxbridge UB8 3PH, Middx, England. Budker Inst Nucl Phys, Novosibirsk 630090, Russia. Univ Calif Irvine, Irvine, CA 92697 USA. Univ Calif Los Angeles, Los Angeles, CA 90024 USA. Univ Calif San Diego, La Jolla, CA 92093 USA. Univ Calif Santa Barbara, Santa Barbara, CA 93106 USA. Univ Calif Santa Cruz, Inst Particle Phys, Santa Cruz, CA 95064 USA. CALTECH, Pasadena, CA 91125 USA. Univ Cincinnati, Cincinnati, OH 45221 USA. Univ Colorado, Boulder, CO 80309 USA. Colorado State Univ, Ft Collins, CO 80523 USA. Tech Univ Dresden, Inst Kern & Teilchenphys, D-01062 Dresden, Germany. Ecole Polytech, F-91128 Palaiseau, France. Univ Edinburgh, Edinburgh EH9 3JZ, Midlothian, Scotland. Elon Univ, Elon College, NC 27244 USA. Univ Ferrara, Dipartimento Fis, I-44100 Ferrara, Italy. Ist Nazl Fis Nucl, I-44100 Ferrara, Italy. Florida A&M Univ, Tallahassee, FL 32307 USA. Ist Nazl Fis Nucl, Lab Nazl Frascati, I-00044 Frascati, Italy. Univ Genoa, Dipartimento Fis, I-16146 Genoa, Italy. Ist Nazl Fis Nucl, I-16146 Genoa, Italy. Harvard Univ, Cambridge, MA 02138 USA. Univ Iowa, Iowa City, IA 52242 USA. Iowa State Univ Sci & Technol, Ames, IA 50011 USA. Lab Accelerateur Lineaire, F-91898 Orsay, France. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Liverpool, Liverpool L69 3BX, Merseyside, England. Univ London Imperial Coll Sci Technol & Med, London SW7 2BW, England. Univ London, London E1 4NS, England. Univ London Royal Holloway & Bedford New Coll, Egham TW20 0EX, Surrey, England. Univ Louisville, Louisville, KY 40292 USA. Univ Manchester, Manchester M13 9PL, Lancs, England. Univ Maryland, College Pk, MD 20742 USA. Univ Massachusetts, Amherst, MA 01003 USA. MIT, Nucl Sci Lab, Cambridge, MA 02139 USA. McGill Univ, Montreal, PQ H3A 2T8, Canada. Univ Milan, Dipartimento Fis, I-20133 Milan, Italy. Ist Nazl Fis Nucl, I-20133 Milan, Italy. Univ Mississippi, University, MS 38677 USA. Univ Montreal, Lab Rene JA Levesque, Montreal, PQ H3C 3J7, Canada. Mt Holyoke Coll, S Hadley, MA 01075 USA. Univ Naples Federico II, Dipartimento Sci Fis, I-80126 Naples, Italy. Ist Nazl Fis Nucl, I-80126 Naples, Italy. Univ Notre Dame, Notre Dame, IN 46556 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Univ Oregon, Eugene, OR 97403 USA. Univ Padua, Dipartimento Fis, I-35131 Padua, Italy. Ist Nazl Fis Nucl, I-35131 Padua, Italy. Univ Paris 06, LPNHE, F-75252 Paris, France. Univ Paris 07, LPNHE, F-75252 Paris, France. Univ Pavia, Dept Elettron, I-27100 Pavia, Italy. Ist Nazl Fis Nucl, I-27100 Pavia, Italy. Univ Penn, Philadelphia, PA 19104 USA. Univ Pisa, Scuola Normale Super Pisa, I-56010 Pisa, Italy. Ist Nazl Fis Nucl, I-56010 Pisa, Italy. Prairie View A&M Univ, Prairie View, TX 77446 USA. Princeton Univ, Princeton, NJ 08544 USA. Univ Roma La Sapienza, Dipartimento Fis, I-00185 Rome, Italy. Ist Nazl Fis Nucl, I-00185 Rome, Italy. Univ Rostock, D-18051 Rostock, Germany. Rutherford Appleton Lab, Didcot OX11 0QX, Oxon, England. CEA Saclay, DAPNIA, F-91191 Gif Sur Yvette, France. Univ S Carolina, Columbia, SC 29208 USA. Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. Stanford Univ, Stanford, CA 94305 USA. TRIUMF, Vancouver, BC V6T 2A3, Canada. Univ Tennessee, Knoxville, TN 37996 USA. Univ Texas, Richardson, TX 75083 USA. Univ Turin, Dipartimento Fis Sperimentale, I-10125 Turin, Italy. Ist Nazl Fis Nucl, I-10125 Turin, Italy. Univ Trieste, Dipartmento Fis, I-34127 Trieste, Italy. Ist Nazl Fis Nucl, I-34127 Trieste, Italy. Vanderbilt Univ, Nashville, TN 37235 USA. Univ Victoria, Victoria, BC V8W 3P6, Canada. Univ Wisconsin, Madison, WI 53706 USA. Yale Univ, New Haven, CT 06511 USA. Univ Perugia, I-06100 Perugia, Italy. Univ Basilicata, I-85100 Potenza, Italy. RP Aubert, B (reprint author), Phys Particules Lab, F-74941 Annecy Le Vieux, France. RI Di Lodovico, Francesca/L-9109-2016; Calcaterra, Alessandro/P-5260-2015; Frey, Raymond/E-2830-2016; Cavallo, Nicola/F-8913-2012; Patrignani, Claudia/C-5223-2009; Monge, Maria Roberta/G-9127-2012; Kravchenko, Evgeniy/F-5457-2015; Martinez Vidal, F*/L-7563-2014; Kolomensky, Yury/I-3510-2015; Lo Vetere, Maurizio/J-5049-2012; Lamanna, Ernesto/C-7658-2012; Pallavicini, Marco/G-5500-2012; Lusiani, Alberto/N-2976-2015; Lusiani, Alberto/A-3329-2016; Morandin, Mauro/A-3308-2016; Valassi, Andrea/K-7506-2012; Telnov, Valery/C-6900-2009; Peters, Klaus/C-2728-2008; de Groot, Nicolo/A-2675-2009; Lista, Luca/C-5719-2008; Schaffner, Stephen/D-1189-2011; Frank, Edward/A-8865-2012; Pia, Maria Grazia/C-7034-2012; Torassa, Ezio/I-1788-2012; Forti, Francesco/H-3035-2011; Rotondo, Marcello/I-6043-2012; de Sangro, Riccardo/J-2901-2012 OI Di Lodovico, Francesca/0000-0003-3952-2175; Calcaterra, Alessandro/0000-0003-2670-4826; Frey, Raymond/0000-0003-0341-2636; Salvatore, Fabrizio/0000-0002-3709-1554; Wilson, Robert/0000-0002-8184-4103; Wallom, David/0000-0001-7527-3407; Della Ricca, Giuseppe/0000-0003-2831-6982; Patrignani, Claudia/0000-0002-5882-1747; Monge, Maria Roberta/0000-0003-1633-3195; Martinez Vidal, F*/0000-0001-6841-6035; Kolomensky, Yury/0000-0001-8496-9975; Lo Vetere, Maurizio/0000-0002-6520-4480; Lamanna, Ernesto/0000-0002-7844-8230; Pallavicini, Marco/0000-0001-7309-3023; Lusiani, Alberto/0000-0002-6876-3288; Lusiani, Alberto/0000-0002-6876-3288; Morandin, Mauro/0000-0003-4708-4240; Valassi, Andrea/0000-0001-9322-9565; Telnov, Valery/0000-0002-8312-8119; Peters, Klaus/0000-0001-7133-0662; Pia, Maria Grazia/0000-0002-3579-9639; Forti, Francesco/0000-0001-6535-7965; Rotondo, Marcello/0000-0001-5704-6163; de Sangro, Riccardo/0000-0002-3808-5455 NR 14 TC 11 Z9 11 U1 0 U2 8 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 10 PY 2001 VL 87 IS 24 AR 241801 DI 10.1103/PhysRevLett.87.241801 PG 7 WC Physics, Multidisciplinary SC Physics GA 500TD UT WOS:000172642100008 ER PT J AU Aubert, B Boutigny, D Gaillard, JM Hicheur, A Karyotakis, Y Lees, JP Robbe, P Tisserand, V Palano, A Chen, GP Chen, JC Qi, ND Rong, G Wang, P Zhu, YS Eigen, G Reinertsen, PL Stugu, B Abbott, B Abrams, GS Borgland, AW Breon, AB Brown, DN Button-Shafer, J Cahn, RN Clark, AR Gill, MS Gritsan, A Groysman, Y Jacobsen, RG Kadel, RW Kadyk, J Kerth, LT Kluth, S Kolomensky, YG Kral, JF LeClerc, C Levi, ME Liu, T Lynch, G Meyer, AB Momayezi, M Oddone, PJ Perazzo, A Pripstein, M Roe, NA Romosan, A Ronan, MT Shelkov, VG Telnov, AV Wenzel, WA Bright-Thomas, RG Harrison, TJ Hawkes, CM Knowles, DJ O'Neale, SW Penny, RC Watson, AT Watson, NK Deppermann, T Goetzen, K Koch, H Krug, J Kunze, M Lewandowski, B Peters, K Schmuecker, H Steinke, M Andress, JC Barlow, NR Bhimji, N Chevalier, N Clark, PJ Cottingham, WN De Groot, N Dyce, N Foster, B McFall, JD Wallom, D Wilson, FF Abe, K Hearty, C Mattison, TS McKenna, JA Thiessen, D Jolly, S McKemey, AK Tinslay, J Blinov, VE Bukin, AD Bukin, DA Buzykaev, AR Golubev, VB Ivanchenko, VN Korol, AA Kravchenko, EA Onuchin, AP Salnikov, AA Serednyakov, SI Skovpen, YI Telnov, VI Yushkov, AN Best, D Lankford, AJ Mandelkern, M McMahon, S Stoker, DR Ahsan, A Arisaka, K Buchanan, C Chun, S Branson, JG MacFarlane, DB Prell, S Rahatlou, S Raven, G Sharma, V Campagnari, C Dahmes, B Hart, PA Kuznetsova, N Levy, SL Long, O Lu, A Richman, JD Verkerke, W Witherell, M Yellin, S Beringer, J Dorfan, DE Eisner, AM Frey, A Grillo, AA Grothe, M Heusch, CA Johnson, RP Kroeger, W Lockman, WS Pulliam, T Sadrozinski, H Schalk, T Schmitz, RE Schumm, BA Seiden, A Turri, M Walkowiak, W Williams, DC Wilson, MG Chen, E Dubois-Felsmann, GP Dvoretskii, A Hitlin, DG Metzler, S Oyang, J Porter, FC Ryd, A Samuel, A Weaver, M Yang, S Zhu, RY Devmal, S Geld, TL Jayatilleke, S Mancinelli, G Meadows, BT Sokoloff, MD Barillari, T Bloom, P Dima, MO Fahey, S Ford, WT Johnson, DR Nauenberg, U Olivas, A Park, H Rankin, P Roy, J Sen, S Smith, JG van Hoek, WC Wagner, DL Blouw, J Harton, JL Krishnamurthy, M Soffer, A Toki, WH Wilson, RJ Zhang, J Brandt, T Brose, J Colberg, T Dahlinger, G Dickopp, M Dubitzky, RS Maly, E Muller-Pfefferkorn, R Otto, S Schubert, KR Schwierz, R Spaan, B Wilden, L Behr, L Bernard, D Bonneaud, GR Brochard, F Cohen-Tanugi, J Ferrag, S Roussot, E T'Jampens, S Thiebaux, C Vasileiadis, G Verderi, M Anjomshoaa, A Bernet, R Khan, A Muheim, F Playfer, S Swain, JE Falbo, M Borean, C Bozzi, C Dittongo, S Folegani, M Piemontese, L Treadwell, E Anulli, F Baldini-Ferroli, R Calcaterra, A de Sangro, R Falciai, D Finocchiaro, G Patteri, P Peruzzi, IM Piccolo, M Xie, Y Zallo, A Bagnasco, S Buzzo, A Contri, R Crosetti, G Fabbricatore, P Farinon, S Lo Vetere, M Macri, M Monge, MR Musenich, R Pallavicini, M Parodi, R Passaggio, S Pastore, FC Patrignani, C Pia, MG Priano, C Robutti, E Santroni, A Morii, M Bartoldus, R Dignan, T Hamilton, R Mallik, U Cochran, J Crawley, HB Fischer, RA Lamsa, J Meyer, WT Rosenberg, EI Benkebil, M Grosdidier, G Hast, C Hocker, A Lacker, HM Laplace, S Lepeltier, V Lutz, AM Plaszczynski, S Schune, MH Trincaz-Duvoid, S Valassi, A Wormser, G Bionta, RM Brigljevic, V Lange, DJ Mugge, M Shi, X van Bibber, K Wenaus, TJ Wright, DM Wuest, CR Carroll, M Fry, JR Gabathuler, E Gamet, R George, M Kay, M Payne, DJ Sloane, RJ Touramanis, C Aspinwall, ML Bowerman, DA Dauncey, PD Egede, U Eschrich, I Gunawardane, NJW Nash, JA Sanders, R Smith, D Azzopardi, DE Back, JJ Dixon, P Harrison, PF Potter, RJL Shorthouse, HW Strother, P Vidal, PB Williams, MI Cowan, G George, S Green, MG Kurup, A Marker, CE McGrath, P McMahon, TR Ricciardi, S Salvatore, F Scott, I Vaitsas, G Brown, D Davis, CL Allison, J Barlow, RJ Boyd, JT Forti, AC Fullwood, J Jackson, F Lafferty, GD Savvas, N Simopoulos, ET Weatherall, JH Farbin, A Jawahery, A Lilllard, V Olsen, J Roberts, DA Schieck, JR Blaylock, G Dallapiccola, C Flood, KT Hertzbach, SS Kofler, R Moore, TB Staengle, H Willocq, S Brau, B Cowan, R Sciolla, G Taylor, F Yamamoto, RK Milek, M Patel, PM Trischuk, J Lanni, F Palombo, F Bauer, JM Booke, M Cremaldi, L Eschenburg, V Kroger, R Reidy, J Sanders, DA Summers, DJ Martin, JR Nief, JY Seitz, R Taras, P Zacek, V Nicholson, H Sutton, CS Cartaro, C Cavallo, N De Nardo, G Fabozzi, F Gatto, C Lista, L Paolucci, R Piccolo, D Sciacca, C LoSecco, JM Alsmiller, JRG Gabriel, TA Handler, T Brau, J Frey, R Iwasaki, M Sinev, NB Strom, D Colecchia, F Dal Corso, F Dorigo, A Galeazzi, F Margoni, M Michelon, G Morandin, M Posocco, M Rotondo, M Simonetto, F Stroili, R Torassa, E Voci, C Benayoun, M Briand, H Chauveau, J David, P de la Vaissiere, C Del Buono, L Hamon, O Le Diberder, F Leruste, P Lory, J Roos, L Stark, J Versille, S Manfredi, PF Re, V Speziali, V Frank, ED Gladney, L Guo, QH Panetta, JH Angelini, C Batignani, G Bettarini, S Bondioli, M Carpinelli, M Forti, F Giorgi, MA Lusiani, A Martinez-Vidal, F Morganti, M Neri, N Paoloni, E Rama, M Rizzo, G Sandrelli, F Simi, G Triggiani, G Walsh, J Haire, M Judd, D Paick, K Turnbull, L Wagoner, DE Albert, J Bula, C Elmer, P Lu, C McDonald, KT Miftakov, V Schaffner, SF Smith, AJS Tumanov, A Varnes, EW Cavoto, G del Re, D Faccini, R Ferrarotto, F Ferroni, F Fratini, K Lamanna, E Leonardi, E Mazzoni, MA Morganti, S Piredda, G Tehrani, FS Serra, M Voena, C Christ, S Waldi, R Adye, T Franek, B Geddes, NI Gopal, GP Xella, SM Aleksan, R De Domenico, G Emery, S Gaidot, A Ganzhur, SF Giraud, PF de Monchenault, GH Kozanecki, W Langer, M London, GW Mayer, B Serfass, B Vasseur, G Yeche, C Zito, M Copty, N Purohit, MV Singh, H Yumiceva, FX Adam, I Anthony, PL Aston, D Baird, K Bloom, E Boyarski, AM Bulos, F Calderini, G Claus, R Convery, MR Coupal, DP Coward, DH Dorfan, J Doser, M Dunwoodie, W Field, RC Glanzman, T Godfrey, GL Gowdy, SJ Grosso, P Himel, T Huffer, ME Innes, WR Jessop, CP Kelsey, MH Kim, P Kocian, ML Langenegger, U Leith, DWGS Luitz, S Luth, V Lynch, HL Marsiske, H Menke, S Messner, R Moffeit, KC Mount, R Muller, DR O'Grady, CP Perl, M Petrak, S Quinn, H Ratcliff, BN Robertson, SH Rochester, LS Roodman, A Schietinger, T Schindler, RH Schwiening, J Serbo, VV Snyder, A Soha, A Spanier, SM Stelzer, J Su, D Sullivan, MK Tanaka, HA Va'vra, J Wagner, SR Weinstein, AJR Wisniewski, WJ Wright, DH Young, CC Burchat, PR Cheng, CH Kirkby, D Meyer, TI Roat, C De Silva, A Henderson, R Bugg, W Cohn, H Weidemann, AW Izen, JM Kitayama, I Lou, XC Turcotte, M Bianchi, F Bona, M Di Girolamo, B Gamba, D Smol, A Zanin, D Bosisio, L Della Ricca, G Lanceri, L Pompili, A Poropat, P Vuagnin, G Panvini, RS Brown, CM Kowalewski, R Roney, JM Band, HR Charles, E Dasu, S Di Lodovico, F Eichenbaum, AM Hu, H Johnson, JR Liu, R Nielsen, J Pan, Y Prepost, R Scott, IJ Sekula, SJ von Wimmersperg-Toeller, JH Wu, SL Yu, Z Zobernig, H Kordich, TMB Neal, H AF Aubert, B Boutigny, D Gaillard, JM Hicheur, A Karyotakis, Y Lees, JP Robbe, P Tisserand, V Palano, A Chen, GP Chen, JC Qi, ND Rong, G Wang, P Zhu, YS Eigen, G Reinertsen, PL Stugu, B Abbott, B Abrams, GS Borgland, AW Breon, AB Brown, DN Button-Shafer, J Cahn, RN Clark, AR Gill, MS Gritsan, A Groysman, Y Jacobsen, RG Kadel, RW Kadyk, J Kerth, LT Kluth, S Kolomensky, YG Kral, JF LeClerc, C Levi, ME Liu, T Lynch, G Meyer, AB Momayezi, M Oddone, PJ Perazzo, A Pripstein, M Roe, NA Romosan, A Ronan, MT Shelkov, VG Telnov, AV Wenzel, WA Bright-Thomas, RG Harrison, TJ Hawkes, CM Knowles, DJ O'Neale, SW Penny, RC Watson, AT Watson, NK Deppermann, T Goetzen, K Koch, H Krug, J Kunze, M Lewandowski, B Peters, K Schmuecker, H Steinke, M Andress, JC Barlow, NR Bhimji, N Chevalier, N Clark, PJ Cottingham, WN De Groot, N Dyce, N Foster, B McFall, JD Wallom, D Wilson, FF Abe, K Hearty, C Mattison, TS McKenna, JA Thiessen, D Jolly, S McKemey, AK Tinslay, J Blinov, VE Bukin, AD Bukin, DA Buzykaev, AR Golubev, VB Ivanchenko, VN Korol, AA Kravchenko, EA Onuchin, AP Salnikov, AA Serednyakov, SI Skovpen, YI Telnov, VI Yushkov, AN Best, D Lankford, AJ Mandelkern, M McMahon, S Stoker, DR Ahsan, A Arisaka, K Buchanan, C Chun, S Branson, JG MacFarlane, DB Prell, S Rahatlou, S Raven, G Sharma, V Campagnari, C Dahmes, B Hart, PA Kuznetsova, N Levy, SL Long, O Lu, A Richman, JD Verkerke, W Witherell, M Yellin, S Beringer, J Dorfan, DE Eisner, AM Frey, A Grillo, AA Grothe, M Heusch, CA Johnson, RP Kroeger, W Lockman, WS Pulliam, T Sadrozinski, H Schalk, T Schmitz, RE Schumm, BA Seiden, A Turri, M Walkowiak, W Williams, DC Wilson, MG Chen, E Dubois-Felsmann, GP Dvoretskii, A Hitlin, DG Metzler, S Oyang, J Porter, FC Ryd, A Samuel, A Weaver, M Yang, S Zhu, RY Devmal, S Geld, TL Jayatilleke, S Mancinelli, G Meadows, BT Sokoloff, MD Barillari, T Bloom, P Dima, MO Fahey, S Ford, WT Johnson, DR Nauenberg, U Olivas, A Park, H Rankin, P Roy, J Sen, S Smith, JG van Hoek, WC Wagner, DL Blouw, J Harton, JL Krishnamurthy, M Soffer, A Toki, WH Wilson, RJ Zhang, J Brandt, T Brose, J Colberg, T Dahlinger, G Dickopp, M Dubitzky, RS Maly, E Muller-Pfefferkorn, R Otto, S Schubert, KR Schwierz, R Spaan, B Wilden, L Behr, L Bernard, D Bonneaud, GR Brochard, F Cohen-Tanugi, J Ferrag, S Roussot, E T'Jampens, S Thiebaux, C Vasileiadis, G Verderi, M Anjomshoaa, A Bernet, R Khan, A Muheim, F Playfer, S Swain, JE Falbo, M Borean, C Bozzi, C Dittongo, S Folegani, M Piemontese, L Treadwell, E Anulli, F Baldini-Ferroli, R Calcaterra, A de Sangro, R Falciai, D Finocchiaro, G Patteri, P Peruzzi, IM Piccolo, M Xie, Y Zallo, A Bagnasco, S Buzzo, A Contri, R Crosetti, G Fabbricatore, P Farinon, S Lo Vetere, M Macri, M Monge, MR Musenich, R Pallavicini, M Parodi, R Passaggio, S Pastore, FC Patrignani, C Pia, MG Priano, C Robutti, E Santroni, A Morii, M Bartoldus, R Dignan, T Hamilton, R Mallik, U Cochran, J Crawley, HB Fischer, RA Lamsa, J Meyer, WT Rosenberg, EI Benkebil, M Grosdidier, G Hast, C Hocker, A Lacker, HM Laplace, S Lepeltier, V Lutz, AM Plaszczynski, S Schune, MH Trincaz-Duvoid, S Valassi, A Wormser, G Bionta, RM Brigljevic, V Lange, DJ Mugge, M Shi, X van Bibber, K Wenaus, TJ Wright, DM Wuest, CR Carroll, M Fry, JR Gabathuler, E Gamet, R George, M Kay, M Payne, DJ Sloane, RJ Touramanis, C Aspinwall, ML Bowerman, DA Dauncey, PD Egede, U Eschrich, I Gunawardane, NJW Nash, JA Sanders, R Smith, D Azzopardi, DE Back, JJ Dixon, P Harrison, PF Potter, RJL Shorthouse, HW Strother, P Vidal, PB Williams, MI Cowan, G George, S Green, MG Kurup, A Marker, CE McGrath, P McMahon, TR Ricciardi, S Salvatore, F Scott, I Vaitsas, G Brown, D Davis, CL Allison, J Barlow, RJ Boyd, JT Forti, AC Fullwood, J Jackson, F Lafferty, GD Savvas, N Simopoulos, ET Weatherall, JH Farbin, A Jawahery, A Lilllard, V Olsen, J Roberts, DA Schieck, JR Blaylock, G Dallapiccola, C Flood, KT Hertzbach, SS Kofler, R Moore, TB Staengle, H Willocq, S Brau, B Cowan, R Sciolla, G Taylor, F Yamamoto, RK Milek, M Patel, PM Trischuk, J Lanni, F Palombo, F Bauer, JM Booke, M Cremaldi, L Eschenburg, V Kroger, R Reidy, J Sanders, DA Summers, DJ Martin, JR Nief, JY Seitz, R Taras, P Zacek, V Nicholson, H Sutton, CS Cartaro, C Cavallo, N De Nardo, G Fabozzi, F Gatto, C Lista, L Paolucci, R Piccolo, D Sciacca, C LoSecco, JM Alsmiller, JRG Gabriel, TA Handler, T Brau, J Frey, R Iwasaki, M Sinev, NB Strom, D Colecchia, F Dal Corso, F Dorigo, A Galeazzi, F Margoni, M Michelon, G Morandin, M Posocco, M Rotondo, M Simonetto, F Stroili, R Torassa, E Voci, C Benayoun, M Briand, H Chauveau, J David, P de la Vaissiere, C Del Buono, L Hamon, O Le Diberder, F Leruste, P Lory, J Roos, L Stark, J Versille, S Manfredi, PF Re, V Speziali, V Frank, ED Gladney, L Guo, QH Panetta, JH Angelini, C Batignani, G Bettarini, S Bondioli, M Carpinelli, M Forti, F Giorgi, MA Lusiani, A Martinez-Vidal, F Morganti, M Neri, N Paoloni, E Rama, M Rizzo, G Sandrelli, F Simi, G Triggiani, G Walsh, J Haire, M Judd, D Paick, K Turnbull, L Wagoner, DE Albert, J Bula, C Elmer, P Lu, C McDonald, KT Miftakov, V Schaffner, SF Smith, AJS Tumanov, A Varnes, EW Cavoto, G del Re, D Faccini, R Ferrarotto, F Ferroni, F Fratini, K Lamanna, E Leonardi, E Mazzoni, MA Morganti, S Piredda, G Tehrani, FS Serra, M Voena, C Christ, S Waldi, R Adye, T Franek, B Geddes, NI Gopal, GP Xella, SM Aleksan, R De Domenico, G Emery, S Gaidot, A Ganzhur, SF Giraud, PF de Monchenault, GH Kozanecki, W Langer, M London, GW Mayer, B Serfass, B Vasseur, G Yeche, C Zito, M Copty, N Purohit, MV Singh, H Yumiceva, FX Adam, I Anthony, PL Aston, D Baird, K Bloom, E Boyarski, AM Bulos, F Calderini, G Claus, R Convery, MR Coupal, DP Coward, DH Dorfan, J Doser, M Dunwoodie, W Field, RC Glanzman, T Godfrey, GL Gowdy, SJ Grosso, P Himel, T Huffer, ME Innes, WR Jessop, CP Kelsey, MH Kim, P Kocian, ML Langenegger, U Leith, DWGS Luitz, S Luth, V Lynch, HL Marsiske, H Menke, S Messner, R Moffeit, KC Mount, R Muller, DR O'Grady, CP Perl, M Petrak, S Quinn, H Ratcliff, BN Robertson, SH Rochester, LS Roodman, A Schietinger, T Schindler, RH Schwiening, J Serbo, VV Snyder, A Soha, A Spanier, SM Stelzer, J Su, D Sullivan, MK Tanaka, HA Va'vra, J Wagner, SR Weinstein, AJR Wisniewski, WJ Wright, DH Young, CC Burchat, PR Cheng, CH Kirkby, D Meyer, TI Roat, C De Silva, A Henderson, R Bugg, W Cohn, H Weidemann, AW Izen, JM Kitayama, I Lou, XC Turcotte, M Bianchi, F Bona, M Di Girolamo, B Gamba, D Smol, A Zanin, D Bosisio, L Della Ricca, G Lanceri, L Pompili, A Poropat, P Vuagnin, G Panvini, RS Brown, CM Kowalewski, R Roney, JM Band, HR Charles, E Dasu, S Di Lodovico, F Eichenbaum, AM Hu, H Johnson, JR Liu, R Nielsen, J Pan, Y Prepost, R Scott, IJ Sekula, SJ von Wimmersperg-Toeller, JH Wu, SL Yu, Z Zobernig, H Kordich, TMB Neal, H CA BABAR Collaboration TI Search for the decay B-0 ->gamma gamma SO PHYSICAL REVIEW LETTERS LA English DT Article ID PHYSICS AB We present a limit on the branching fraction for the decay B-0 --> gamma gamma using data collected at the Y(4S) resonance with the BABAR detector at the PEP-II asymmetric energy e(+)e(-) collider Based on the observation of one event in the signal region, out of a sample of 21.3 x 10(6) e(+)e(-) --> Y(4S) --> B(B) over bar decays, we establish an upper limit on the branching fraction of B (B-0 --> gamma gamma) < 1.7 x 10(-6) at the 90% confidence level. This result substantially improves upon existing limits. C1 Phys Particules Lab, F-74941 Annecy Le Vieux, France. Univ Bari, Dipartmento Fis, I-70126 Bari, Italy. Ist Nazl Fis Nucl, I-70126 Bari, Italy. Inst High Energy Phys, Beijing 100039, Peoples R China. Univ Bergen, Inst Phys, N-5007 Bergen, Norway. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Birmingham, Birmingham B15 2TT, W Midlands, England. Ruhr Univ Bochum, Inst Expt Phys 1, D-44780 Bochum, Germany. Univ Bristol, Bristol BS8 1TL, Avon, England. Univ British Columbia, Vancouver, BC V6T 1Z1, Canada. Brunel Univ, Uxbridge UB8 3PH, Middx, England. Budker Inst Nucl Phys, Novosibirsk 630090, Russia. Univ Calif Irvine, Irvine, CA 92697 USA. Univ Calif Los Angeles, Los Angeles, CA 90024 USA. Univ Calif San Diego, La Jolla, CA 92093 USA. Univ Calif Santa Barbara, Santa Barbara, CA 93106 USA. Univ Calif Santa Cruz, Inst Particle Phys, Santa Cruz, CA 95064 USA. CALTECH, Pasadena, CA 91125 USA. Univ Cincinnati, Cincinnati, OH 45221 USA. Univ Colorado, Boulder, CO 80309 USA. Colorado State Univ, Ft Collins, CO 80523 USA. Tech Univ Dresden, Inst Kern & Teilchenphys, D-01062 Dresden, Germany. Ecole Polytech, F-91128 Palaiseau, France. Univ Edinburgh, Edinburgh EH9 3JZ, Midlothian, Scotland. Elon Univ, Elon Univ, NC 27244 USA. Univ Ferrara, Dipartmento Fis, I-44100 Ferrara, Italy. Ist Nazl Fis Nucl, I-44100 Ferrara, Italy. Florida A&M Univ, Tallahassee, FL 32307 USA. Nazl Frascati Lab, I-00044 Frascati, Italy. Ist Nazl Fis Nucl, I-00044 Frascati, Italy. Univ Genoa, Dipartimento Fis, I-16146 Genoa, Italy. Ist Nazl Fis Nucl, I-16146 Genoa, Italy. Harvard Univ, Cambridge, MA 02138 USA. Univ Iowa, Iowa City, IA 52242 USA. Iowa State Univ Sci & Technol, Ames, IA 50011 USA. Lab Accelerateur Lineaire, F-91898 Orsay, France. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Liverpool, Liverpool L69 3BX, Merseyside, England. Univ London Imperial Coll Sci Technol & Med, London SW7 2BW, England. Univ London, London E1 4NS, England. Univ London Royal Holloway & Bedford New Coll, Egham TW20 0EX, Surrey, England. Univ Louisville, Louisville, KY 40292 USA. Univ Manchester, Manchester M13 9PL, Lancs, England. Univ Maryland, College Pk, MD 20742 USA. Univ Massachusetts, Amherst, MA 01003 USA. MIT, Nucl Sci Lab, Cambridge, MA 02139 USA. McGill Univ, Montreal, PQ H3A 2T8, Canada. Univ Milan, Dipartimento Fis, I-20133 Milan, Italy. Ist Nazl Fis Nucl, I-20133 Milan, Italy. Univ Mississippi, University, MS 38677 USA. Univ Montreal, Lab Rene JA Levesque, Montreal, PQ H3C 3J7, Canada. Mt Holyoke Coll, S Hadley, MA 01075 USA. Univ Naples Federico 2, Dipartimento Sci Fis, I-80126 Naples, Italy. Ist Nazl Fis Nucl, I-80126 Naples, Italy. Univ Notre Dame, Notre Dame, IN 46556 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Univ Oregon, Eugene, OR 97403 USA. Univ Padua, Dipartimento Fis, I-35131 Padua, Italy. Ist Nazl Fis Nucl, I-35131 Padua, Italy. Univ Paris 06, LPNHE, F-75252 Paris, France. Univ Paris 07, LPNHE, F-75252 Paris, France. Univ Pavia, Dept Elettron, I-27100 Pavia, Italy. Ist Nazl Fis Nucl, I-27100 Pavia, Italy. Univ Penn, Philadelphia, PA 19104 USA. Univ Pisa, Scuola Normale Super Pisa, I-56010 Pisa, Italy. Ist Nazl Fis Nucl, I-56010 Pisa, Italy. Prairie View A&M Univ, Prairie View, TX 77446 USA. Princeton Univ, Princeton, NJ 08544 USA. Univ Roma La Sapienza, Dipartimento Fis, I-00185 Rome, Italy. Ist Nazl Fis Nucl, I-00185 Rome, Italy. Univ Rostock, D-18051 Rostock, Germany. Rutherford Appleton Lab, Didcot OX11 0QX, Oxon, England. CEA Saclay, DAPNIA, F-91191 Gif Sur Yvette, France. Univ S Carolina, Columbia, SC 29208 USA. Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. Stanford Univ, Stanford, CA 94305 USA. TRIUMF, Vancouver, BC V6T 2A3, Canada. Univ Tennessee, Knoxville, TN 37996 USA. Univ Texas, Richardson, TX 75083 USA. Univ Turin, Dipartimento Fis Sperimentale, I-10125 Turin, Italy. Ist Nazl Fis Nucl, I-10125 Turin, Italy. Univ Trieste, Dipartmento Fis, I-34127 Trieste, Italy. Ist Nazl Fis Nucl, I-34127 Trieste, Italy. Vanderbilt Univ, Nashville, TN 37235 USA. Univ Victoria, Victoria, BC V8W 3P6, Canada. Univ Wisconsin, Madison, WI 53706 USA. Yale Univ, New Haven, CT 06511 USA. Univ Perugia, I-06100 Perugia, Italy. Univ Basilicata, I-85100 Potenza, Italy. RP Aubert, B (reprint author), Phys Particules Lab, F-74941 Annecy Le Vieux, France. RI Della Ricca, Giuseppe/B-6826-2013; Di Lodovico, Francesca/L-9109-2016; Calcaterra, Alessandro/P-5260-2015; Frey, Raymond/E-2830-2016; Cavallo, Nicola/F-8913-2012; Patrignani, Claudia/C-5223-2009; Monge, Maria Roberta/G-9127-2012; Kravchenko, Evgeniy/F-5457-2015; Martinez Vidal, F*/L-7563-2014; Kolomensky, Yury/I-3510-2015; Lo Vetere, Maurizio/J-5049-2012; Lamanna, Ernesto/C-7658-2012; Pallavicini, Marco/G-5500-2012; Lusiani, Alberto/N-2976-2015; Lusiani, Alberto/A-3329-2016; Morandin, Mauro/A-3308-2016; Peters, Klaus/C-2728-2008; Rotondo, Marcello/I-6043-2012; de Sangro, Riccardo/J-2901-2012; de Groot, Nicolo/A-2675-2009; Lista, Luca/C-5719-2008; Schaffner, Stephen/D-1189-2011; Valassi, Andrea/K-7506-2012; Telnov, Valery/C-6900-2009; Frank, Edward/A-8865-2012; Pia, Maria Grazia/C-7034-2012; Torassa, Ezio/I-1788-2012; Forti, Francesco/H-3035-2011 OI Della Ricca, Giuseppe/0000-0003-2831-6982; Di Lodovico, Francesca/0000-0003-3952-2175; Calcaterra, Alessandro/0000-0003-2670-4826; Frey, Raymond/0000-0003-0341-2636; Patrignani, Claudia/0000-0002-5882-1747; Monge, Maria Roberta/0000-0003-1633-3195; Martinez Vidal, F*/0000-0001-6841-6035; Kolomensky, Yury/0000-0001-8496-9975; Lo Vetere, Maurizio/0000-0002-6520-4480; Lamanna, Ernesto/0000-0002-7844-8230; Pallavicini, Marco/0000-0001-7309-3023; Lusiani, Alberto/0000-0002-6876-3288; Lusiani, Alberto/0000-0002-6876-3288; Morandin, Mauro/0000-0003-4708-4240; Peters, Klaus/0000-0001-7133-0662; Rotondo, Marcello/0000-0001-5704-6163; de Sangro, Riccardo/0000-0002-3808-5455; Valassi, Andrea/0000-0001-9322-9565; Telnov, Valery/0000-0002-8312-8119; Pia, Maria Grazia/0000-0002-3579-9639; Forti, Francesco/0000-0001-6535-7965 NR 12 TC 11 Z9 11 U1 1 U2 8 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 10 PY 2001 VL 87 IS 24 AR 241803 DI 10.1103/PhysRevLett.87.241803 PG 7 WC Physics, Multidisciplinary SC Physics GA 500TD UT WOS:000172642100010 ER PT J AU Back, BB Betts, RR Chang, J Chang, WC Chi, CY Chu, YY Cuniming, JB Dunlop, JC Eldredge, W Fung, SY Ganz, R Garcia, E Gillitzer, A Heintzelman, G Henning, WF Hofman, DJ Holzman, B Kang, JH Kim, EJ Kim, SY Kwon, Y McLeod, D Mignerey, AC Moulson, M Nanal, V Ogilvie, CA Pak, R Ruangma, A Russ, DE Seto, R Stanskas, PJ Stephans, GSF Wang, H Wolfs, FLH Wuosmaa, AH Xiang, H Xu, GH Yao, HB Zou, CM AF Back, BB Betts, RR Chang, J Chang, WC Chi, CY Chu, YY Cuniming, JB Dunlop, JC Eldredge, W Fung, SY Ganz, R Garcia, E Gillitzer, A Heintzelman, G Henning, WF Hofman, DJ Holzman, B Kang, JH Kim, EJ Kim, SY Kwon, Y McLeod, D Mignerey, AC Moulson, M Nanal, V Ogilvie, CA Pak, R Ruangma, A Russ, DE Seto, R Stanskas, PJ Stephans, GSF Wang, H Wolfs, FLH Wuosmaa, AH Xiang, H Xu, GH Yao, HB Zou, CM CA E917 Collaboration TI Antilambda production in Au+Au collisions at 11.7A GeV/c SO PHYSICAL REVIEW LETTERS LA English DT Article ID HEAVY-ION COLLISIONS; ANTIPROTON PRODUCTION; 11.6A GEV/C; STRANGENESS; FLOW; AGS AB We present results for antilambda and antiproton production in Au + Au collisions at 11.7 A GeV/c including spectra and extracted invariant yields for both species in central and peripheral collisions in the rapidity range 1.0 < v < 1.4. The antilambda yield increases from dN(<()over bar>)/dy = 1.2(-0.6-0.2)(+0.7+0.2) x 10-3 in peripheral collisions to 19(-5-2)(+4+3) x 10(-3) in central collisions. The direct antiproton yield is deduced from the measured total antiproton spectra to extract the ratio of antilambda-to-direct-antiproton production. The <()over bar>/(p) over bar ratio near midrapidity increases from 0.26(-0.15-0.4)(+0.19+0.5) in peripheral collisions to 3.6(-1.8-1.1)(+4/7+2.7) in central collisions, a value larger than current theoretical estimates. C1 Argonne Natl Lab, Argonne, IL 60439 USA. Univ Illinois, Chicago, IL 60607 USA. Univ Calif Riverside, Riverside, CA 92521 USA. Columbia Univ, Nevis Lab, Irvington, NY 10533 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. MIT, Cambridge, MA 02139 USA. Univ Maryland, College Pk, MD 20742 USA. Yonsei Univ, Seoul 120749, South Korea. Univ Rochester, Rochester, NY 14627 USA. RP Back, BB (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Mignerey, Alice/D-6623-2011; seto, richard/G-8467-2011; OI Holzman, Burt/0000-0001-5235-6314 NR 23 TC 7 Z9 7 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 10 PY 2001 VL 87 IS 24 AR 242301 DI 10.1103/PhysRevLett.87.242301 PG 4 WC Physics, Multidisciplinary SC Physics GA 500TD UT WOS:000172642100013 ER PT J AU Blake, GR Palstra, TTM Ren, Y Nugroho, AA Menovsky, AA AF Blake, GR Palstra, TTM Ren, Y Nugroho, AA Menovsky, AA TI Transition between orbital orderings in YVO3 SO PHYSICAL REVIEW LETTERS LA English DT Article ID MOTT-INSULATOR YVO3; MAGNETIC-PROPERTIES; LAMNO3; DIFFRACTION; CRYSTAL; YTIO3 AB Evidence has been found for a change in the ordered occupation of the vanadium d orbitals at the 77 K phase transition in YVO3, manifested by a change in the type of Jahn-Teller distortion. The orbital ordering above 77 K is not destroyed at the magnetic ordering temperature of 116 K, but is present as far as a second structural phase transition at 200 K. The transition between orbital orderings is caused by an increase in octahedral tilting with decreasing temperature. C1 Univ Groningen, Solid State Chem Lab, Ctr Mat Sci, NL-9747 AG Groningen, Netherlands. Argonne Natl Lab, Argonne, IL 60439 USA. Univ Amsterdam, Van Der Waals Zeeman Inst, NL-1018 XE Amsterdam, Netherlands. RP Palstra, TTM (reprint author), Univ Groningen, Solid State Chem Lab, Ctr Mat Sci, Nijenborgh 4, NL-9747 AG Groningen, Netherlands. EM Palstra@chem.rug.nl RI Nugroho, Agustinus Agung/E-5977-2010; Palstra, Thomas/K-1961-2013 OI Nugroho, Agustinus Agung/0000-0002-1785-4008; Palstra, Thomas/0000-0001-5239-3115 NR 21 TC 94 Z9 94 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 10 PY 2001 VL 87 IS 24 AR 245501 DI 10.1103/PhysRevLett.87.245501 PG 4 WC Physics, Multidisciplinary SC Physics GA 500TD UT WOS:000172642100027 PM 11736512 ER PT J AU Covington, AM Aguilar, A Covington, IR Gharaibeh, M Shirley, CA Phaneuf, RA Alvarez, I Cisneros, C Hinojosa, G Bozek, JD Dominguez, I Sant'Anna, MM Schlachter, AS Berrah, N Nahar, SN McLaughlin, BM AF Covington, AM Aguilar, A Covington, IR Gharaibeh, M Shirley, CA Phaneuf, RA Alvarez, I Cisneros, C Hinojosa, G Bozek, JD Dominguez, I Sant'Anna, MM Schlachter, AS Berrah, N Nahar, SN McLaughlin, BM TI Photoionization of metastable O(+) ions: Experiment and theory SO PHYSICAL REVIEW LETTERS LA English DT Article ID ATOMIC NITROGEN; CROSS-SECTIONS; OSCILLATOR-STRENGTHS; OPACITY CALCULATIONS; OXYGEN; EXCITATION; STATES AB High-resolution absolute experimental measurements and two independent theoretical calculations were performed for photoionization of O(+) ions from the (2)P(0) and (2)D(0) metastable levels and from the (4)S(0) ground state in the photon energy range 30-35.5 eV. This is believed to be the first comparison of experiment and theory to be reported for photoionization from metastable states of ions. While there is correspondence between the predicted and measured positions and relative strengths of the resonances, the cross-section magnitudes and fine structure are sensitive to the choice of basis states. C1 Univ Nevada, Dept Phys, Reno, NV 89557 USA. Univ Nacl Autonoma Mexico, Ctr Ciencias Fis, Cuernavaca 62131, Morelos, Mexico. Univ Calif Berkeley, Lawrence Berkeley Lab, Adv Light Source, Berkeley, CA 94720 USA. Western Michigan Univ, Dept Phys, Kalamazoo, MI 49008 USA. Ohio State Univ, Dept Astron, Columbus, OH 43210 USA. Harvard Smithsonian Ctr Astrophys, Inst Theoret Atom & Mol Phys, Cambridge, MA 02138 USA. RP Covington, AM (reprint author), Univ Nevada, Dept Phys, MS 220, Reno, NV 89557 USA. RI Bozek, John/E-4689-2010; Sant'Anna, Marcelo/B-9355-2013; Bozek, John/E-9260-2010; Dominguez-Lopez, Ivan/B-6072-2016 OI Sant'Anna, Marcelo/0000-0001-5342-5799; Bozek, John/0000-0001-7486-7238; Dominguez-Lopez, Ivan/0000-0001-8084-8711 NR 20 TC 48 Z9 48 U1 0 U2 2 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 10 PY 2001 VL 87 IS 24 AR 243002 DI 10.1103/PhysRevLett.87.243002 PG 4 WC Physics, Multidisciplinary SC Physics GA 500TD UT WOS:000172642100016 PM 11736500 ER PT J AU Maslov, S Zhang, YC AF Maslov, S Zhang, YC TI Extracting hidden information from knowledge networks SO PHYSICAL REVIEW LETTERS LA English DT Article AB We develop a method allowing us to reconstruct individual tastes of customers from a sparsely connected network of their opinions on products, services, or each other. Two distinct phase transitions occur as the density of edges in this network is increased: Above the first, macroscopic prediction of tastes becomes possible; while above the second, all unknown opinions can be uniquely reconstructed. We illustrate our ideas using a simple Gaussian model, which we study using both field-theoretical methods and numerical simulations. We point out a potential relevance of our approach to the field of bioinformatics. C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Univ Fribourg, Inst Phys Theor, CH-1700 Fribourg, Switzerland. RP Maslov, S (reprint author), Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RI Maslov, Sergei/C-2397-2009 OI Maslov, Sergei/0000-0002-3701-492X NR 9 TC 72 Z9 74 U1 2 U2 9 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 10 PY 2001 VL 87 IS 24 AR 248701 DI 10.1103/PhysRevLett.87.248701 PG 4 WC Physics, Multidisciplinary SC Physics GA 500TD UT WOS:000172642100059 PM 11736544 ER PT J AU Morr, DK Balatsky, AV AF Morr, DK Balatsky, AV TI Proximity effects and quantum dissipation in the chains of YBa2Cu3O6+x SO PHYSICAL REVIEW LETTERS LA English DT Article ID SCANNING TUNNELING SPECTROSCOPY; PENETRATION-DEPTH; SUPERCONDUCTIVITY; YBA2CU3O7-DELTA; FLUCTUATIONS; ANISOTROPY; PLANES; WAVES AB We argue that the results of recent scanning tunneling microscopy, angle-resolved photoemission, and infrared spectroscopy experiments on the CuO chains of YBa2Cu3O6+x are consistently explained within a proximity model by the interplay of a coherent chain-plane and an incoherent and indirect interchain coupling. We show that the CuO2 planes act as an Ohmic heat bath for the chain fermions and induce a substantial quantum dissipation. Below the planar T-c, charge excitations in the chains acquire a universal superconducting gap. C1 Univ Illinois, Dept Phys, Chicago, IL 60607 USA. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Morr, DK (reprint author), Univ Illinois, Dept Phys, Chicago, IL 60607 USA. OI Morr, Dirk/0000-0003-3692-2835 NR 17 TC 24 Z9 25 U1 1 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 10 PY 2001 VL 87 IS 24 AR 247002 DI 10.1103/PhysRevLett.87.247002 PG 4 WC Physics, Multidisciplinary SC Physics GA 500TD UT WOS:000172642100046 PM 11736531 ER PT J AU Ng, JST Chen, P Baldis, H Bolton, P Cline, D Craddock, W Crawford, C Decker, FJ Field, C Fukui, Y Kumar, V Iverson, R King, F Kirby, RE Nakajima, K Noble, R Ogata, A Raimondi, P Walz, D Weidemann, AW AF Ng, JST Chen, P Baldis, H Bolton, P Cline, D Craddock, W Crawford, C Decker, FJ Field, C Fukui, Y Kumar, V Iverson, R King, F Kirby, RE Nakajima, K Noble, R Ogata, A Raimondi, P Walz, D Weidemann, AW TI Observation of plasma focusing of a 28.5 GeV positron beam SO PHYSICAL REVIEW LETTERS LA English DT Article ID LENS AB The observation of plasma focusing of a 28.5 GeV positron beam is reported. The plasma was formed by ionizing a nitrogen jet only 3 mm. thick. Simultaneous focusing in both transverse dimensions was observed with effective focusing strengths of order tesla per micron. The minimum area of the beam spot was reduced by a factor of 2.0 +/- 0.3 by the plasma. The longitudinal beam envelope was measured and compared with numerical calculations. C1 Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Univ Calif Los Angeles, Los Angeles, CA 90024 USA. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. High Energy Accelerator Lab, Tsukuba, Ibaraki 3050801, Japan. Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. Univ Calif Davis, Dept Appl Sci, Davis, CA 95616 USA. Hiroshima Univ, Higashihiroshima 7398526, Japan. RP Ng, JST (reprint author), Stanford Linear Accelerator Ctr, POB 4349, Stanford, CA 94309 USA. NR 14 TC 51 Z9 52 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 10 PY 2001 VL 87 IS 24 AR 244801 DI 10.1103/PhysRevLett.87.244801 PG 4 WC Physics, Multidisciplinary SC Physics GA 500TD UT WOS:000172642100023 PM 11736507 ER PT J AU Ohldag, H Regan, TJ Stohr, J Scholl, A Nolting, F Luning, J Stamm, C Anders, S White, RL AF Ohldag, H Regan, TJ Stohr, J Scholl, A Nolting, F Luning, J Stamm, C Anders, S White, RL TI Spectroscopic identification and direct imaging of interfacial magnetic spins SO PHYSICAL REVIEW LETTERS LA English DT Article ID X-RAY-ABSORPTION; EXCHANGE BIAS; DICHROISM SPECTROMICROSCOPY; ANISOTROPY; INJECTION; FILMS; FE; CO AB Using x-ray absorption spectromicroscopy we have imaged the uncompensated spins induced at the surface of antiferromagnetic (AFM) NiO(100) by deposition of ferromagnetic (FM) Co. These spins align parallel to the AFM spins in NiO(100) and align the FM spins in Co. The uncompensated interfacial spins arise from an ultrathin CoNiOx layer that is formed upon Co deposition through reduction of the NiO surface. The interfacial Ni spins are discussed in terms of the "uncompensated spins" at AFM/FM interfaces long held responsible for coercivity increases and exchange bias. We find a direct correlation between their number and the size of the coercivity. C1 Stanford Synchrotron Radiat Lab, Stanford, CA 94309 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Adv Light Source, Berkeley, CA 94720 USA. Stanford Univ, Dept Appl Phys, Stanford, CA 94305 USA. Stanford Univ, Dept Mat Sci & Engn, Stanford, CA 94305 USA. Univ Dusseldorf, Inst Angew Phys, D-40225 Dusseldorf, Germany. RP Ohldag, H (reprint author), Stanford Synchrotron Radiat Lab, POB 20450, Stanford, CA 94309 USA. RI Stamm, Christian/G-4814-2013; Ohldag, Hendrik/F-1009-2014; Raoux, Simone/G-3920-2016 OI Stamm, Christian/0000-0001-5611-9084; NR 21 TC 168 Z9 168 U1 2 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 10 PY 2001 VL 87 IS 24 AR 247201 DI 10.1103/PhysRevLett.87.247201 PG 4 WC Physics, Multidisciplinary SC Physics GA 500TD UT WOS:000172642100052 PM 11736537 ER PT J AU Spataru, CD Cazalilla, MA Rubio, A Benedict, LX Echenique, PM Louie, SG AF Spataru, CD Cazalilla, MA Rubio, A Benedict, LX Echenique, PM Louie, SG TI Anomalous quasiparticle lifetime in graphite: Band structure effects SO PHYSICAL REVIEW LETTERS LA English DT Article ID FEMTOSECOND PHOTOEMISSION SPECTROSCOPY; FERMI-LIQUID BEHAVIOR; INELASTIC LIFETIMES; ENERGY-DEPENDENCE; ELECTRON LIFETIME; QUASI-PARTICLE; HOT-ELECTRONS; NOBLE-METALS AB We report ab initio calculations of quasiparticle lifetimes in graphite, as determined from the imaginary part of the self-energy operator within the GW approximation. The inverse lifetime in the energy range from 0.5 to 3.5 eV above the Fermi level presents significant deviations from the quadratic behavior naively expected from Fermi liquid theory. The deviations are explained in terms of the unique features of the band structure of this material. We also discuss the experimental results from different groups and make some predictions for future experiments. C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Brown Univ, Dept Phys, Providence, RI 02912 USA. Kimika Fak, Donostia San Sebastian 20080, Spain. Donostia Int Phys Ctr, Donostia San Sebastian 20018, Spain. Lawrence Livermore Natl Lab, H Div, Phys & Adv Technol Directorate, Livermore, CA 94550 USA. CSIC UPV EHU, Ctr Mixto, Donostia San Sebastian 20080, Spain. RP Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. RI CSIC-UPV/EHU, CFM/F-4867-2012; Cazalilla, Miguel/A-1366-2013; Rubio, Angel/A-5507-2008; DONOSTIA INTERNATIONAL PHYSICS CTR., DIPC/C-3171-2014 OI Cazalilla, Miguel/0000-0002-2994-2873; Rubio, Angel/0000-0003-2060-3151; NR 31 TC 54 Z9 55 U1 1 U2 11 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 10 PY 2001 VL 87 IS 24 AR 246405 DI 10.1103/PhysRevLett.87.246405 PG 4 WC Physics, Multidisciplinary SC Physics GA 500TD UT WOS:000172642100039 PM 11736524 ER PT J AU Timmermans, E AF Timmermans, E TI Degenerate fermion gas heating by hole creation SO PHYSICAL REVIEW LETTERS LA English DT Article ID BOSE-EINSTEIN CONDENSATION; ATTRACTIVE INTERACTIONS; ATOMIC GAS; LI-6; RECOMBINATION; TRANSITION AB Loss processes that remove particles from an atom trap leave holes behind in the single particle distribution if the trapped gas is a degenerate fem-lion system. The appearance of holes increases the temperature and we show that the heating (i) is significant if the initial temperature is well below the Fermi temperature T-F, and (ii) increases the temperature to T greater than or equal to T-F/4 after half of the system's lifetime, regardless of the initial temperature. The hole heating has important consequences for the prospect of observing Cooper pairing in atom traps. C1 Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Timmermans, E (reprint author), Los Alamos Natl Lab, Div Theoret, T4, Los Alamos, NM 87545 USA. NR 20 TC 44 Z9 44 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 10 PY 2001 VL 87 IS 24 AR 240403 DI 10.1103/PhysRevLett.87.240403 PG 4 WC Physics, Multidisciplinary SC Physics GA 500TD UT WOS:000172642100004 PM 11736488 ER PT J AU Williamson, AJ Hood, RQ Grossman, JC AF Williamson, AJ Hood, RQ Grossman, JC TI Linear-scaling quantum Monte Carlo calculations SO PHYSICAL REVIEW LETTERS LA English DT Article ID WANNIER FUNCTIONS; WAVE-FUNCTIONS; SIMULATIONS; SOLIDS AB A method is presented for using truncated, maximally localized Wannier functions to introduce sparsity into the Slater determinant part of the trial wave function in quantum Monte Carlo calculations. When combined with an efficient numerical evaluation of these localized orbitals, the dominant cost in the calculation, namely, the evaluation of the Slater determinant, scales linearly with system size. This technique is applied to accurate total energy calculation of hydrogenated silicon clusters and carbon fullerenes containing 20-1000 valence electrons. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Williamson, AJ (reprint author), Lawrence Livermore Natl Lab, 7000 East Ave, Livermore, CA 94550 USA. NR 18 TC 111 Z9 112 U1 0 U2 4 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 10 PY 2001 VL 87 IS 24 AR 246406 DI 10.1103/PhysRevLett.87.246406 PG 4 WC Physics, Multidisciplinary SC Physics GA 500TD UT WOS:000172642100040 PM 11736525 ER PT J AU Xiong, F Dutta, D Xu, W Anderson, B Auberbach, L Averett, T Bertozzi, W Black, T Calarco, J Cardman, L Cates, GD Chai, ZW Chen, JP Choi, S Chudakov, E Churchwell, S Corrado, GS Crawford, C Dale, D Deur, A Djawotho, P Filippone, BW Finn, JM Gao, H Gilman, R Glamazdin, AV Glashausser, C Glockle, W Golak, J Gomez, J Gorbenko, VG Hansen, JO Hersman, FW Higinbotham, DW Holmes, R Howell, CR Hughes, E Humensky, B Incerti, S de Jager, CW Jensen, JS Jiang, X Jones, CE Jones, M Kahl, R Kamada, H Kievsky, A Kominis, I Korsch, W Kramer, K Kumbartzki, G Kuss, M Lakuriqi, E Liang, M Liyanage, N LeRose, J Malov, S Margaziotis, DJ Martin, JW McCormick, K McKeown, RD McIlhany, K Meziani, ZE Michaels, R Miller, GW Pace, E Pavlin, T Petratos, GG Pomatsalyuk, RI Pripstein, D Prout, D Ransome, RD Roblin, Y Rvachev, M Saha, A Salme, G Schnee, M Shin, T Slifer, K Souder, PA Strauch, S Suleiman, R Sutter, M Tipton, B Todor, L Viviani, M Vlahovic, B Watson, J Williamson, CF Witala, H Wojtsekhowski, B Yeh, J Zolnierczuk, P AF Xiong, F Dutta, D Xu, W Anderson, B Auberbach, L Averett, T Bertozzi, W Black, T Calarco, J Cardman, L Cates, GD Chai, ZW Chen, JP Choi, S Chudakov, E Churchwell, S Corrado, GS Crawford, C Dale, D Deur, A Djawotho, P Filippone, BW Finn, JM Gao, H Gilman, R Glamazdin, AV Glashausser, C Glockle, W Golak, J Gomez, J Gorbenko, VG Hansen, JO Hersman, FW Higinbotham, DW Holmes, R Howell, CR Hughes, E Humensky, B Incerti, S de Jager, CW Jensen, JS Jiang, X Jones, CE Jones, M Kahl, R Kamada, H Kievsky, A Kominis, I Korsch, W Kramer, K Kumbartzki, G Kuss, M Lakuriqi, E Liang, M Liyanage, N LeRose, J Malov, S Margaziotis, DJ Martin, JW McCormick, K McKeown, RD McIlhany, K Meziani, ZE Michaels, R Miller, GW Pace, E Pavlin, T Petratos, GG Pomatsalyuk, RI Pripstein, D Prout, D Ransome, RD Roblin, Y Rvachev, M Saha, A Salme, G Schnee, M Shin, T Slifer, K Souder, PA Strauch, S Suleiman, R Sutter, M Tipton, B Todor, L Viviani, M Vlahovic, B Watson, J Williamson, CF Witala, H Wojtsekhowski, B Yeh, J Zolnierczuk, P TI Precision measurement of the spin-dependent asymmetry in the threshold region of (3)(H)over-right-arrow ((e)over-right-arrow, e ') SO PHYSICAL REVIEW LETTERS LA English DT Article ID ELECTRIC FORM-FACTOR; STRUCTURE-FUNCTION G(1)(N); DEEP-INELASTIC SCATTERING; QUASI-ELASTIC SCATTERING; POLARIZED HE-3; INCLUSIVE SCATTERING; RADIATIVE-CAPTURE; EXCHANGE CURRENTS; NEUTRON; H-3 AB We present the first precision measurement of the spin-dependent asymmetry in the threshold region of (3)(H) over right arrowe((e) over right arrow ,e') at Q(2) values of 0.1 and 0.2 (GeV/c)(2). The agreement between the data and nonrelativistic Faddeev calculations which include both final-state interactions and meson-exchange current effects is very good at Q(2) = 0.1 (GeV/c)(2), while a small discrepancy at Q(2) = 0.2 (GeV/c)(2) is observed. C1 MIT, Cambridge, MA 02139 USA. CALTECH, Pasadena, CA 91125 USA. Calif State Univ Los Angeles, Los Angeles, CA 90032 USA. Coll William & Mary, Williamsburg, VA 23187 USA. Duke Univ, Durham, NC 27708 USA. Ist Nazl Fis Nucl, Sez Pisa, I-56010 Pisa, Italy. Ist Nazl Fis Nucl, Sez Roma, I-00185 Rome, Italy. Ist Nazl Fis Nucl, Sez Tor Vergata, I-00133 Rome, Italy. Jagiellonian Univ, Inst Phys, PL-30059 Krakow, Poland. Kharkov Phys & Technol Inst, UA-310108 Kharkov, Ukraine. Kent State Univ, Kent, OH 44242 USA. Univ Clermont Ferrand, LPC, F-63177 Aubiere, France. MIT, Cambridge, MA 02139 USA. N Carolina Cent Univ, Durham, NC 27707 USA. Old Dominion Univ, Norfolk, VA 23508 USA. Princeton Univ, Princeton, NJ 08544 USA. Ruhr Univ Bochum, D-44780 Bochum, Germany. Rutgers State Univ, Piscataway, NJ 08855 USA. Syracuse Univ, Syracuse, NY 13244 USA. Temple Univ, Philadelphia, PA 19122 USA. Thomas Jefferson Natl Accelerator Facil, Newport News, VA 23606 USA. Univ Kentucky, Lexington, KY 40506 USA. Univ New Hampshire, Durham, NH 03824 USA. Univ Roma Tor Vergata, Dipartimento Fis, I-00173 Rome, Italy. Univ Virginia, Charlottesville, VA 22903 USA. RP Xiong, F (reprint author), MIT, 77 Massachusetts Ave, Cambridge, MA 02139 USA. RI kievsky, alejandro/A-7123-2011; Kominis, Iannis/C-5515-2011; Averett, Todd/A-2969-2011; Gao, Haiyan/G-2589-2011; Kuss, Michael/H-8959-2012 NR 43 TC 21 Z9 21 U1 0 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 10 PY 2001 VL 87 IS 24 AR 242501 DI 10.1103/PhysRevLett.87.242501 PG 5 WC Physics, Multidisciplinary SC Physics GA 500TD UT WOS:000172642100014 PM 11736498 ER PT J AU Rozsnyai, BF Albritton, JR Young, DA Sonnad, VN Liberman, DA AF Rozsnyai, BF Albritton, JR Young, DA Sonnad, VN Liberman, DA TI Theory and experiment for ultrahigh pressure shock Hugoniots SO PHYSICS LETTERS A LA English DT Article DE equation of state; shock Hugoniot; ionization ID DENSE MATTER; STATE; EQUATION; ALUMINUM; MBAR; HOT; COMPRESSIBILITY; MODEL AB Several equation of state models for hot. dense matter are compared with experimental data for the shock Hugoniots of beryllium, aluminum, iron, copper, and molybdenum up to extreme pressures. The best models are in good agreement with experiment and with one another, suggesting that our understanding of dense, partially ionized matter is good. (C) 2001 Published by Elsevier Science B.V. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Rozsnyai, BF (reprint author), Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. EM rozsnyai1@llnl.gov NR 30 TC 33 Z9 33 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9601 EI 1873-2429 J9 PHYS LETT A JI Phys. Lett. A PD DEC 10 PY 2001 VL 291 IS 4-5 BP 226 EP 231 DI 10.1016/S0375-9601(01)00661-2 PG 6 WC Physics, Multidisciplinary SC Physics GA 503LB UT WOS:000172799000008 ER PT J AU Berman, GP Borgonovi, F Izrailev, FM Tsifrinovich, VI AF Berman, GP Borgonovi, F Izrailev, FM Tsifrinovich, VI TI Single-pulse preparation of the uniform superpositional state used in quantum algorithms SO PHYSICS LETTERS A LA English DT Article AB We examine a single-pulse preparation of the uniform superpositional wave function, which includes all basis states, in a spin quantum computer. The effective energy spectrum and the errors generated by this pulse are studied in detail. We show that, in spite of the finite width of the energy spectrum bands, amplitude and phase errors can be made reasonably small. (C) 2001 Published by Elsevier Science B.V. C1 Univ Cattolica, Dipartimento Matemat & Fis, I-25121 Brescia, Italy. Los Alamos Natl Lab, CNLS, Los Alamos, NM 87545 USA. Ist Nazl Fis Nucl, Sezione Pavia, Brescia, Italy. Univ Brescia, INFM, Brescia, Italy. Univ Autonoma Puebla, Inst Fis, Puebla 72570, Mexico. Polytech Univ, IDS Dept, Metrotech Ctr, Brooklyn, NY 11201 USA. RP Borgonovi, F (reprint author), Univ Cattolica, Dipartimento Matemat & Fis, Via Musei 41, I-25121 Brescia, Italy. OI borgonovi, fausto/0000-0002-9730-1189 NR 8 TC 3 Z9 3 U1 0 U2 1 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 10 PY 2001 VL 291 IS 4-5 BP 232 EP 236 DI 10.1016/S0375-9601(01)00739-3 PG 5 WC Physics, Multidisciplinary SC Physics GA 503LB UT WOS:000172799000009 ER PT J AU Jackson, GP Lewis, CL Doorn, SK Majidi, V King, FL AF Jackson, GP Lewis, CL Doorn, SK Majidi, V King, FL TI Spectral, spatial and temporal characteristics of a millisecond pulsed glow discharge: metastable argon atom production SO SPECTROCHIMICA ACTA PART B-ATOMIC SPECTROSCOPY LA English DT Article DE pulsed glow discharge; atomic absorbance; atomic emission; laser-induced atomic fluorescence; metastable argon atoms; two-dimensional imaging ID OPTICAL-EMISSION SPECTROMETRY; MASS-SPECTROMETRY; IONIZATION-RECOMBINATION; ABSORPTION SPECTROMETRY; POPULATION-DENSITY; SIGNAL PROFILES; CROSS-SECTIONS; EXCITED IONS; PLASMA; FLUORESCENCE AB Time resolved atomic emission, atomic absorbance, and laser-induced atomic fluorescence measurements of a millisecond pulsed glow discharge, made perpendicular to the insertion probe, provide temporal profiles of 1s(5) (P-3(2)) and 1s(3) (P-3(0)) metastable argon atom populations. Acquisition of these profiles at different spatial positions in the plasma provides data from which two-dimensional spatial plots of relative populations are constructed. Each map, the result of 368 individual pulse profiles, provides insight into the production of metastable argon atoms as a function of time and position within the plasma. During power application, intensities plateau after 3 ms as the plasma reaches a steady state condition. Metastable argon atoms are most abundant 1-2 mm above the cathode surface during this time. Excitation mechanisms such as electron excitation and fast atom/ion impact appear to dominate in this temporal regime. In contrast, argon ion-electron recombination dominates metastable formation after pulse termination. The relative population maximum for metastable argon atoms in the afterpeak shifts to 5-9 mm above the cathode surface. This shift should impact signals for analyte species generated by Penning processes in the plasma. Absorption and fluorescence measurements of the P-3(2) (11.55 eV) and the P-3(0) (11.72 eV) metastable argon atom states indicate possible differences in the populations of these two states between the plateau and afterpeak time regimes. (C) 2001 Elsevier Science B.V. All rights reserved. C1 W Virginia Univ, Dept Chem, Morgantown, WV 26506 USA. Los Alamos Natl Lab, Div Chem, Los Alamos, NM 87545 USA. RP King, FL (reprint author), W Virginia Univ, Dept Chem, POB 6045, Morgantown, WV 26506 USA. RI Jackson, Glen/D-3518-2014 OI Jackson, Glen/0000-0003-0803-6254 NR 45 TC 50 Z9 50 U1 0 U2 13 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0584-8547 J9 SPECTROCHIM ACTA B JI Spectroc. Acta Pt. B-Atom. Spectr. PD DEC 10 PY 2001 VL 56 IS 12 BP 2449 EP 2464 DI 10.1016/S0584-8547(01)00329-9 PG 16 WC Spectroscopy SC Spectroscopy GA 508ZD UT WOS:000173118900010 ER PT J AU Cai, T Shi, F Shen, Z Gierer, M Goldman, AI Kramer, MJ Jenks, CJ Lograsso, TA Delaney, DW Thiel, PA Van Hove, MA AF Cai, T Shi, F Shen, Z Gierer, M Goldman, AI Kramer, MJ Jenks, CJ Lograsso, TA Delaney, DW Thiel, PA Van Hove, MA TI Structural aspects of the fivefold quasicrystalline Al-Cu-Fe surface from STM and dynamical LEED studies SO SURFACE SCIENCE LA English DT Article DE electron solid interactions, scattering, diffraction; scanning tunneling microscopy; electron solid diffraction; low energy electron diffraction (LEED); step formation and bunching; aluminum; alloys; single crystal surfaces; low index single crystal surfaces ID ENERGY-ELECTRON-DIFFRACTION; SCANNING-TUNNELING-MICROSCOPY; AL70PD21MN9 QUASI-CRYSTAL; PD-MN; AL68PD23MN9; ALPDMN; ADSORPTION; ALCUFE AB We investigate the atomic structure of the fivefold surface of an icosahedral Al-Cu-Fe alloy, using scanning tunneling microscopy (STM) imaging and a special dynamical low energy-electron diffraction (LEED) method. STM indicates that the step heights adopt (primarily) two values in the ratio of tau, but the spatial distribution of these two values does not follow a Fibonacci sequence, thus breaking the ideal bulk-like quasicrystalline layer stacking order perpendicular to the surface. The appearance of screw dislocations in the STM images is another indication of imperfect quasicrystallinity. On the other hand, the LEED analysis, which was successfully applied to Al-Pd-Mn in a previous study, is equally successful for Al-Cu Fe. Similar structural features are found for both materials, in particular for interlayer relaxations and surface terminations. Although there is no structural periodicity, there are clear atomic planes in the bulk of the quasicrystal, some of which can be grouped in recurring patterns. The surface tends to form between these grouped layers in both alloys. For Al-Cu-Fe, the step heights measured by STM are consistent with the thicknesses of the grouped layers favored in LEED, These results suggest that the fivefold Al-Cu-Fe surface exhibits a quasicrystalline layering structure, but with stacking defects. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Iowa State Univ, Dept Chem, Ames, IA 50011 USA. Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Sci Mat, Berkeley, CA 94720 USA. Univ Munich, Inst Kristallog & Mineral, D-80333 Munich, Germany. Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Mat Sci & Engn, Ames, IA 50011 USA. Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Adv Light Source, Berkeley, CA 94720 USA. Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. RP Thiel, PA (reprint author), Iowa State Univ, Dept Chem, Ames, IA 50011 USA. RI Van Hove, Michel/A-9862-2008 OI Van Hove, Michel/0000-0002-8898-6921 NR 44 TC 39 Z9 39 U1 0 U2 5 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 10 PY 2001 VL 495 IS 1-2 BP 19 EP 34 DI 10.1016/S0039-6028(01)01500-X PG 16 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA 504VK UT WOS:000172876400003 ER PT J AU Reho, JH Higgins, J Nooijen, M Lehmann, KK Scoles, G Gutowski, M AF Reho, JH Higgins, J Nooijen, M Lehmann, KK Scoles, G Gutowski, M TI Photoinduced nonadiabatic dynamics in quartet Na-3 and K-3 formed using helium nanodroplet isolation SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID SODIUM TRIMER; SPECTROSCOPY; CLUSTERS; STATE; MOTION AB Helium nanodroplet isolation is used to produce van der Waals-bound quartet state alkali trimers (Na-3 and K-3) selectively over the corresponding chemically bound doublet trimers. Frequency-resolved excitation and emission spectroscopy reveals the presence of nonadiabatic spin-flip processes in the electronically excited states. A total of four quartet to quartet electronic transitions are observed: the 2 E-4('),1 E-4<--1 (4)A(2)(') transitions of Na-3 and the 1 (4)A(1)('),2 E-4(')<--1 (4)A(2)(') transitions of K-3. Time-resolved spectroscopy reveals that intersystem crossing times in Na-3 decrease from 1.4 ns after excitation of the 0-0 band to approximately 400 ps for the higher vibronic levels (3,5/2). Analysis of the resonant quartet fluorescence reveals that the excited electronic state cools vibrationally on a time scale that is comparable to, but slower than, the intersystem crossing time. (C) 2001 American Institute of Physics. C1 Princeton Univ, Dept Chem, Princeton, NJ 08544 USA. Pacific NW Natl Lab, Richland, WA 99352 USA. Univ Gdansk, Dept Chem, PL-80952 Gdansk, Poland. RP Reho, JH (reprint author), E Carolina Univ, Dept Chem, E 5th St, Greenville, NC 27858 USA. NR 31 TC 44 Z9 44 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 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD DEC 8 PY 2001 VL 115 IS 22 BP 10265 EP 10274 DI 10.1063/1.1418248 PG 10 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 496GC UT WOS:000172387000023 ER PT J AU Xie, DQ Guo, H Peterson, KA AF Xie, DQ Guo, H Peterson, KA TI Ab initio characterization of low-lying triplet state potential-energy surfaces and vibrational frequencies in the Wulf band of ozone SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID FOURIER-TRANSFORM SPECTROMETRY; EXCITED-STATES; ELECTRONIC STATES; ABSORPTION-SPECTROSCOPY; ROTATIONAL STRUCTURE; METASTABLE STATE; CHAPPUIS BAND; BASIS-SETS; SPECTRA; PHOTODISSOCIATION AB Accurate ab initio potential-energy surfaces of the (3)A(2) and B-3(1) states of ozone and their nonadiabatic coupling are reported near the ground-state equilibrium geometry using an internally contracted multireference configuration interaction method. These coupled three-dimensional potential-energy surfaces enable the first theoretical characterization of all three vibrational modes in the Wulf band. Reasonably good agreement with recent experimental observations is obtained. (C) 2001 American Institute of Physics. C1 Univ New Mexico, Dept Chem, Albuquerque, NM 87131 USA. Washington State Univ, Dept Chem, Richland, WA 99352 USA. Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Guo, H (reprint author), Univ New Mexico, Dept Chem, Albuquerque, NM 87131 USA. RI Guo, Hua/J-2685-2014 OI Guo, Hua/0000-0001-9901-053X NR 30 TC 12 Z9 12 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 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD DEC 8 PY 2001 VL 115 IS 22 BP 10404 EP 10408 DI 10.1063/1.1417502 PG 5 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 496GC UT WOS:000172387000036 ER PT J AU Zheng, JW Chumanov, G Cotton, TM AF Zheng, JW Chumanov, G Cotton, TM TI Photoinduced electron transfer at the surface of nanosized silver particles as monitored by EPR spectroscopy SO CHEMICAL PHYSICS LETTERS LA English DT Article ID REDUCTION; PHOTOREDUCTION; METHYLVIOLOGEN; RESONANCE; ZEOLITES; RAMAN AB EPR spectroscopy was employed in study of photoinduced electron transfer on nanosized silver particles. Radicals were observed for the silver colloid with methylviologen (MV), nitrophenol and methanol with irradiation of UV lights. The wavelength dependence of EPR spectra of silver colloid with methanol indicates that plasmon resonance may be critical for the formation of the radicals on the nanosized silver particles. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Suzhou Univ, Dept Chem, Suzhou 215006, Peoples R China. Iowa State Univ, Ames Lab, Ames, IA 50011 USA. RP Zheng, JW (reprint author), Suzhou Univ, Dept Chem, Suzhou 215006, Peoples R China. NR 13 TC 8 Z9 8 U1 0 U2 12 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0009-2614 J9 CHEM PHYS LETT JI Chem. Phys. Lett. PD DEC 7 PY 2001 VL 349 IS 5-6 BP 367 EP 370 DI 10.1016/S0009-2614(01)01149-6 PG 4 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 502RG UT WOS:000172756100004 ER PT J AU Coronado, EA Xing, JH Miller, WH AF Coronado, EA Xing, JH Miller, WH TI Ultrafast non-adiabatic dynamics of systems with multiple surface crossings: a test of the Meyer-Miller Hamiltonian with semiclassical initial value representation methods SO CHEMICAL PHYSICS LETTERS LA English DT Article ID COMPLEX MOLECULAR-SYSTEMS; THERMAL RATE CONSTANTS; QUANTUM DYNAMICS; PHOTODISSOCIATION DYNAMICS; WAVEPACKET PROPAGATION; ELECTRONIC DEGREES; FREEDOM; APPROXIMATIONS; SIMULATIONS AB Three three-state models have been studied to test the capabilities of the Meyer-Miller Hamiltonian studying nonadiabatic photodissociation dynamics, within the framework of the semiclassical initial value representation (SC-IVR). The absorption spectra and the evolution of the electronic populations were calculated using the SC-IVR methodology, and they both show excellent agreement with accurate quantum results. A linearized version (LSC-IVR) was also tested, and it describes the dynamics well for short times but becomes less accurate at longer time, (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Chem Sci, Kennet S Pitzer Ctr Theoret Chem,Dept Chem, Berkeley, CA 94720 USA. RP Miller, WH (reprint author), Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Chem Sci, Kennet S Pitzer Ctr Theoret Chem,Dept Chem, Berkeley, CA 94720 USA. EM miller@neon.cchem.berkeley.edu RI Xing, Jianhua/A-8101-2012; icmol, icmol/I-5784-2015; OI Xing, Jianhua/0000-0002-3700-8765; Coronado, Eduardo A./0000-0002-2251-1501 NR 34 TC 16 Z9 16 U1 4 U2 8 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0009-2614 J9 CHEM PHYS LETT JI Chem. Phys. Lett. PD DEC 7 PY 2001 VL 349 IS 5-6 BP 521 EP 529 DI 10.1016/S0009-2614(01)01242-8 PG 9 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 502RG UT WOS:000172756100029 ER PT J AU Yu, HG Muckerman, JT Sears, TJ AF Yu, HG Muckerman, JT Sears, TJ TI A theoretical study of the potential energy surface for the reaction OH+CO -> H+CO2 SO CHEMICAL PHYSICS LETTERS LA English DT Article ID INFRARED-ABSORPTION SPECTRUM; HIGH-PRESSURE RANGE; TRANS-HOCO; QUANTUM CALCULATIONS; DOCO; PHOTOIONIZATION; OH+CO->CO2+H; SPECTROSCOPY; EXCITATIONS; ENERGETICS AB Stationary points on the OH + CO --> H + CO2 potential energy surface are calculated using an extrapolated full coupled-cluster/complete basis set (FCC/CBS) method. The trans-HOCO intermediate is found to lie 30.10 kcal/mole below the OH + CO dissociation limit. For the forward reaction, the vibrationally adiabatic ground-state barrier height is predicted to be 1.03 kcal/mole. Finally, a many-body expansion potential energy surface for HOCO is obtained by fitting to the new ab initio results. (C) 2001 Published by Elsevier Science B.V. C1 Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. RP Muckerman, JT (reprint author), Brookhaven Natl Lab, Dept Chem, Bldg 555A, Upton, NY 11973 USA. RI Muckerman, James/D-8752-2013; Sears, Trevor/B-5990-2013; Yu, Hua-Gen/N-7339-2015 OI Sears, Trevor/0000-0002-5559-0154; NR 31 TC 118 Z9 118 U1 3 U2 18 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0009-2614 J9 CHEM PHYS LETT JI Chem. Phys. Lett. PD DEC 7 PY 2001 VL 349 IS 5-6 BP 547 EP 554 DI 10.1016/S0009-2614(01)01238-6 PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 502RG UT WOS:000172756100032 ER PT J AU Tandori, J Baciou, L Alexov, E Maroti, P Schiffer, M Hanson, DK Sebban, P AF Tandori, J Baciou, L Alexov, E Maroti, P Schiffer, M Hanson, DK Sebban, P TI Revealing the involvement of extended hydrogen bond networks in the cooperative function between distant sites in bacterial reaction centers SO JOURNAL OF BIOLOGICAL CHEMISTRY LA English DT Article ID PHOTOSYNTHETIC REACTION-CENTER; MUTANT REACTION CENTERS; RHODOBACTER-SPHAEROIDES; ELECTRON-TRANSFER; PROTON-TRANSFER; FREE-ENERGY; Q(B); MUTATIONS; DELIVERY; QUINONES AB In reaction center proteins of photosynthetic bacteria, the amplitude of proton uptake induced by the one-electron reduction of either of the two quinone electron acceptors (Q(A) and Q(B)) is an intrinsic observable of the electrostatic interactions associated with the redox function of the complex. We report here that, in Rhodobacter capsulatus, complete restoration of proton uptake (upon formation of Q(A)(-) and Q(B)(-)) to the level found in the wild type is observed in a mutant reaction center in which a tyrosine substitution in the QA environment (Ala(M274) --> Tyr) is coupled with mutations of acidic residues near QR (Glu(L212) --> Ala/Asp(L213) --> Ala) that initially cancel the proton uptake above pH 8. This result demonstrates that proton uptake occurs by strong cooperation between structural motifs, such as hydrogen-bonded networks, that span the 18 Angstrom distance between the two quinone acceptors. C1 CNRS, Ctr Genet Mol, F-91198 Gif Sur Yvette, France. Univ Szeged, Dept Biophys, H-6722 Szeged, Hungary. Columbia Univ, Howard Hughes Med Inst, New York, NY 10032 USA. Columbia Univ, Dept Biochem, New York, NY 10032 USA. Argonne Natl Lab, Biosci Div, Argonne, IL 60439 USA. RP Sebban, P (reprint author), CNRS, Ctr Genet Mol, F-91198 Gif Sur Yvette, France. NR 20 TC 24 Z9 25 U1 1 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 7 PY 2001 VL 276 IS 49 BP 45513 EP 45515 DI 10.1074/jbc.C100537200 PG 3 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 499LR UT WOS:000172573100005 PM 11604387 ER PT J AU Curtright, T Zachos, C AF Curtright, T Zachos, C TI Negative probability and uncertainty relations SO MODERN PHYSICS LETTERS A LA English DT Article DE uncertainty relations; star product; Wigner functions; phase-space quantization; negative probability ID PHASE-SPACE; WIGNER FUNCTION; FUNDAMENTALS; MECHANICS AB A concise derivation of all uncertainty relations is given entirely within the context of phase-space quantization, without recourse to operator methods, to the direct use of Weyl's correspondence, or to marginal distributions of x and p. C1 Univ Miami, Dept Phys, Coral Gables, FL 33124 USA. Argonne Natl Lab, Div High Energy Phys, Argonne, IL 60439 USA. RP Curtright, T (reprint author), Univ Miami, Dept Phys, Box 248046, Coral Gables, FL 33124 USA. RI zachos, cosmas/C-4366-2014; Curtright, Thomas/B-6840-2015; OI zachos, cosmas/0000-0003-4379-3875; Curtright, Thomas/0000-0001-7031-5604 NR 34 TC 16 Z9 16 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 0217-7323 J9 MOD PHYS LETT A JI Mod. Phys. Lett. A PD DEC 7 PY 2001 VL 16 IS 37 BP 2381 EP 2385 DI 10.1142/S021773230100576X PG 5 WC Physics, Nuclear; Physics, Particles & Fields; Physics, Mathematical SC Physics GA 517QP UT WOS:000173621600004 ER PT J AU Klein, PB Binari, SC Ikossi, K Wickenden, AE Koleske, DD Henry, RL AF Klein, PB Binari, SC Ikossi, K Wickenden, AE Koleske, DD Henry, RL TI Effect of deep traps on sheet charge in AlGaN/GaN high electron mobility transistors SO ELECTRONICS LETTERS LA English DT Article ID FIELD-EFFECT TRANSISTORS; GAN AB The same traps that produce current collapse in AlGaN/GaN high electron mobility transistors are also shown to limit the sheet charge that is attainable in these devices by the trapping of channel carriers at equilibrium (no applied bias). In the present case. this reduction in sheet charge was found comparable to that induced by current collapse. C1 USN, Res Lab, Washington, DC 20375 USA. USA, Res Lab, Adelphi, MD 20783 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Klein, PB (reprint author), USN, Res Lab, 4555 Overlook Ave SW, Washington, DC 20375 USA. NR 9 TC 10 Z9 10 U1 0 U2 3 PU IEE-INST ELEC ENG PI HERTFORD PA MICHAEL FARADAY HOUSE SIX HILLS WAY STEVENAGE, HERTFORD SG1 2AY, ENGLAND SN 0013-5194 J9 ELECTRON LETT JI Electron. Lett. PD DEC 6 PY 2001 VL 37 IS 25 BP 1550 EP 1551 DI 10.1049/el:20011040 PG 2 WC Engineering, Electrical & Electronic SC Engineering GA 504JZ UT WOS:000172854700039 ER PT J AU Schmidt, TJ Ross, PN Markovic, NM AF Schmidt, TJ Ross, PN Markovic, NM TI Temperature-dependent surface electrochemistry on Pt single crystals in alkaline electrolyte: Part 1: CO oxidation SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID CARBON-MONOXIDE; ACID-SOLUTIONS; PT-RU; HYDROGEN ELECTROCHEMISTRY; OXYGEN REDUCTION; H-2/CO MIXTURES; ELECTROOXIDATION; PLATINUM; INTERFACE; ELECTROCATALYSIS AB In this work we studied the continuous electrooxidation of CO dissolved in 0.1 M KOH electrolyte (COb) on Pt(hkl) at 275 and 333 K, respectively. The results clearly demonstrate that Pt(hkl) electrodes in alkaline electrolyte represent a highly active system for COb oxidation. Significant reaction rates are observed even in the potential region for hydrogen underpotential deposition (H-upd). The COb oxidation on Pt(hkl) surfaces proceeds through a Langmuir-Hinshelwood type reaction between the adsorbed states of CO and OHad, the latter forming selectively at the defect/step sites. The coexistence of OHad in the Hupd potential region implies that the potential-dependent surface coverages by H-upd and OHad in alkaline solutions cannot be obtained by simple coulometry. The kinetics of CO oxidation on Pt(hkl) surfaces is found to vary with crystal face. The difference in activity is attributed to the structure-sensitive adsorption of OHad on the defect/step sites and mobility of adsorbed CO (COad). C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Markovic, NM (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RI Schmidt, Thomas/A-2586-2010 OI Schmidt, Thomas/0000-0002-1636-367X NR 25 TC 56 Z9 57 U1 2 U2 28 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 6 PY 2001 VL 105 IS 48 BP 12082 EP 12086 DI 10.1021/jp0124037 PG 5 WC Chemistry, Physical SC Chemistry GA 499ZC UT WOS:000172600100023 ER PT J AU Alcock, C Allsman, RA Alves, DR Axelrod, TS Becker, AC Bennett, DP Cook, KH Drake, AJ Freeman, KC Geha, M Griest, K Keller, SC Lehner, MJ Marshall, SL Minniti, D Nelson, CA Peterson, BA Popowski, P Pratt, MR Quinn, PJ Stubbs, CW Sutherland, W Tomaney, AB Vandehel, T Welch, D AF Alcock, C Allsman, RA Alves, DR Axelrod, TS Becker, AC Bennett, DP Cook, KH Drake, AJ Freeman, KC Geha, M Griest, K Keller, SC Lehner, MJ Marshall, SL Minniti, D Nelson, CA Peterson, BA Popowski, P Pratt, MR Quinn, PJ Stubbs, CW Sutherland, W Tomaney, AB Vandehel, T Welch, D TI Direct detection of a microlens in the Milky Way SO NATURE LA English DT Article ID MACHO PROJECT; M DWARFS AB The nature of dark matter remains mysterious, with luminous material accounting for at most similar to 25 per cent of the baryons in the Universe(1,2). We accordingly undertook a survey looking for the microlensing of stars in the Large Magellanic Cloud (LMC) to determine the fraction of Galactic dark matter contained in massive compact halo objects (MACHOs). The presence of the dark matter would be revealed by gravitational lensing of the light from an LMC star as the foreground dark matter moves across the line of sight. The duration of the lensing event is the key observable parameter, but gives non-unique solutions when attempting to estimate the mass, distance and transverse velocity of the lens. The survey results to date indicate that between 8 and 50 per cent of the baryonic mass of the Galactic halo is in the form of MACHOs (ref. 3), but removing the degeneracy by identifying a lensing object would tighten the constraints on the mass in MACHOs. Here we report a direct image of a microlens, revealing it to be a nearby low-mass star in the disk of the Milky Way. This is consistent with the expected frequency of nearby stars acting as lenses, and demonstrates a direct determination of a lens mass from a microlensing event. Complete solutions such as this for halo microlensing events will probe directly the nature of the MACHOs. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Calif Berkeley, Ctr Particle Astrophys, Berkeley, CA 94720 USA. Univ Penn, Dept Phys & Astron, Philadelphia, PA 19104 USA. Australian Natl Univ, Supercomp Facil, Canberra, ACT 0200, Australia. Space Telescope Sci Inst, Baltimore, MD 21218 USA. Mt Stromlo & Siding Spring Observ, Res Sch Anat, Weston, ACT 2611, Australia. Bell Labs, Lucent Technol, Murray Hill, NJ 07974 USA. Univ Notre Dame, Dept Phys, Notre Dame, IN 46556 USA. Univ Calif Santa Cruz, Dept Astron & Astrophys, Santa Cruz, CA 95064 USA. Univ Calif San Diego, Dept Phys, San Diego, CA 92039 USA. Pontificia Univ Catolica Chile, Dept Astron, Santiago 22, Chile. Univ Washington, Dept Phys & Astron, Seattle, WA 98195 USA. European So Observ, D-85748 Munich, Germany. Univ Oxford, Dept Phys, Oxford OX1 3RH, England. McMaster Univ, Dept Phys & Astron, Hamilton, ON L8S 4M1, Canada. RP Nelson, CA (reprint author), Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RI Stubbs, Christopher/C-2829-2012; OI Stubbs, Christopher/0000-0003-0347-1724; Sutherland, William/0000-0002-6498-0437; Lehner, Matthew/0000-0003-4077-0985 NR 13 TC 96 Z9 96 U1 1 U2 3 PU MACMILLAN PUBLISHERS LTD PI LONDON PA PORTERS SOUTH, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD DEC 6 PY 2001 VL 414 IS 6864 BP 617 EP 619 DI 10.1038/414617a PG 3 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 498WB UT WOS:000172535600041 PM 11740553 ER PT J AU Schafer, T Son, DT Stephanov, MA Toublan, D Verbaarschot, JJM AF Schafer, T Son, DT Stephanov, MA Toublan, D Verbaarschot, JJM TI Kaon condensation and Goldstone's theorem SO PHYSICS LETTERS B LA English DT Article DE QCD partition function; Kaon condensation; finite isospin density; Goldstone's theorem; quadratic dispersion relations; low-energy effective theory; Chiral perturbation theory ID CHIRAL PERTURBATION-THEORY; COLOR-FLAVOR-LOCKING; HIGH-DENSITY QCD; PHASE AB We consider QCD at a nonzero chemical potential for strangeness. At a critical value of the chemical potential equal to the kaon mass, kaon condensation occurs through a continuous phase transition. We show that in the limit of exact isospin symmetry a Goldstone boson with the dispersion relation E similar to p(2) appears in the kaon condensed phase. At the same time, the number of the Goldstone bosons is less than the number of broken generators. Both phenomena are familiar in nonrelativistic systems. We interpret our results in terms of a Goldstone boson counting rule found previously by Nielsen and Chadha. We also formulate a criterion sufficient for the equality between the number of Goldstone bosons and the number of broken generators. (C) 2001 Published by Elsevier Science B.V. C1 SUNY Stony Brook, Dept Phys & Astron, Stony Brook, NY 11794 USA. Columbia Univ, Dept Phys, New York, NY 10027 USA. Univ Illinois, Dept Phys, Chicago, IL 60607 USA. Univ Illinois, Dept Phys, Urbana, IL 61801 USA. Brookhaven Natl Lab, RIKEN BNL Res Ctr, Upton, NY 11973 USA. RP Toublan, D (reprint author), SUNY Stony Brook, Dept Phys & Astron, Stony Brook, NY 11794 USA. NR 25 TC 91 Z9 92 U1 1 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 6 PY 2001 VL 522 IS 1-2 BP 67 EP 75 DI 10.1016/S0370-2693(01)01265-5 PG 9 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 496UP UT WOS:000172415700010 ER PT J AU Bryant, PL Harwell, CR Mrse, AA Emery, EF Gan, ZH Caldwell, T Reyes, AP Kuhns, P Hoyt, DW Simeral, LS Hall, RW Butler, LG AF Bryant, PL Harwell, CR Mrse, AA Emery, EF Gan, ZH Caldwell, T Reyes, AP Kuhns, P Hoyt, DW Simeral, LS Hall, RW Butler, LG TI Structural characterization of MAO and related aluminum complexes. 1. Solid-state Al-27 NMR with comparison to EFG tensors from ab initio molecular orbital calculations SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID QUADRUPOLE COUPLING-CONSTANTS; OLEFIN POLYMERIZATION; RESONANCE SPECTRA; FLAME RETARDANTS; PHASE-SEPARATION; FIELD-SWEPT; SPECTROSCOPY; METHYLALUMINOXANE; ANDALUSITE; MICROWAVE AB Experimental and ab initio molecular orbital techniques are developed for study of aluminum species with large quadrupole coupling constants to test structural models for methylaluminoxanes (MAO). The techniques are applied to nitrogen- and oxygen-containing complexes of aluminum and to solid MAO isolated from active commercial MAO preparations. (Aminato)- and (propanolato)aluminum clusters with 3-, 4-, and 6-coordinate aluminum sites are studied with three Al-27 NMR techniques optimized for large Al quadrupole coupling constants: field-swept, frequency-stepped, and high-field MAS NMR. Four-membered (aminato)aluminum complexes with AlN4 coordination yield slightly smaller C-q values than similar AlN2C2 Sites: 12.2 vs 15.8 MHz. Planar 3-coordinate AlN2C sites have the largest C-q values, 37 MHz. In all cases, molecular orbital calculations of the electric field gradient tensors yields C-q and eta values that match with experiment, even for a large hexameric (aminato) aluminum cage. A D-3d symmetry hexaaluminum oxane cluster, postulated as a model for MAO, yields a calculated C-q of -23.7 MHz, eta = 0.7474, and predicts a spectrum that is too broad to match the field-swept NMR of methylaluminoxane, which shows at least three sites, all with C-q values greater than 15 MHz but less than 21 MHz. Thus, the proposed hexaaluminum cluster, with its strained four-membered rings, is not a major component of MAO. However, calculations for dimers of the cage complex, either edge-bridged or face-bridged, show a much closer match to experiment. Also, MAO preparations differ, with a gel form of MAO having significantly larger Al-27 C-q values than a nongel form, a conclusion reached on the basis of Al-27 NMR line widths in field-swept NMR spectra acquired from 13 to 24 T. C1 Albemarle Corp, Baton Rouge, LA 70898 USA. Louisiana State Univ, Dept Chem, Baton Rouge, LA 70803 USA. Natl High Magnet Field Lab, Tallahassee, FL 32310 USA. Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. Louisiana State Univ, Dept Phys & Astron, Baton Rouge, LA 70803 USA. RP Simeral, LS (reprint author), Albemarle Corp, POB 14799, Baton Rouge, LA 70898 USA. RI Gan, Zhehong/C-2400-2011; Hoyt, David/H-6295-2013; Butler, Leslie/D-1636-2016 OI Butler, Leslie/0000-0003-1547-608X NR 56 TC 46 Z9 46 U1 1 U2 19 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 5 PY 2001 VL 123 IS 48 BP 12009 EP 12017 DI 10.1021/ja011092a PG 9 WC Chemistry, Multidisciplinary SC Chemistry GA 499VL UT WOS:000172591000022 PM 11724609 ER PT J AU Levitskaia, TG Moyer, BA Bonnesen, PV Marchand, AP Krishnudu, K Chen, ZB Huang, ZL Kruger, HG McKim, AS AF Levitskaia, TG Moyer, BA Bonnesen, PV Marchand, AP Krishnudu, K Chen, ZB Huang, ZL Kruger, HG McKim, AS TI Novel approach to sodium hydroxide separation: Synergistic pseudo-hydroxide extraction by a fluorinated alcohol and cage-functionalized crown ethers SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID METAL-IONS; SELECTIVITY; ALKALI C1 Oak Ridge Natl Lab, Div Chem Sci, Oak Ridge, TN 37830 USA. Univ N Texas, Dept Chem, NT Stn, Denton, TX 76203 USA. RP Moyer, BA (reprint author), Oak Ridge Natl Lab, Div Chem Sci, POB 2008, Oak Ridge, TN 37830 USA. RI Solominow, Sonia/A-4021-2008; Bonnesen, Peter/A-1889-2016; Moyer, Bruce/L-2744-2016; Kruger, Gert/B-1687-2009 OI Bonnesen, Peter/0000-0002-1397-8281; Moyer, Bruce/0000-0001-7484-6277; Kruger, Gert/0000-0003-0606-2053 NR 18 TC 26 Z9 26 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 5 PY 2001 VL 123 IS 48 BP 12099 EP 12100 DI 10.1021/ja016590y PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA 499VL UT WOS:000172591000037 PM 11724624 ER PT J AU McGrath, WJ Baniecki, ML Peters, E Green, DT Mangel, WF AF McGrath, WJ Baniecki, ML Peters, E Green, DT Mangel, WF TI Roles of two conserved cysteine residues in the activation of human adenovirus proteinase SO BIOCHEMISTRY LA English DT Article ID VIRAL-DNA; PROTEASE; PEPTIDE; PAPAIN; CATALYSIS; COFACTORS; MECHANISM; BINDING; TYPE-2; VIRION AB roles of two conserved cysteine residues involved in the activation of the adenovirus proteinase (AVP) were investigated. AVP requires two cofactors for maximal activity, the 11-amino acid peptide pVIc (GVQSLKRRRCF) and the viral DNA. In the AVP-pVIc crystal structure, conserved Cys 104 of AVP has formed a disulfide bond with conserved Cys 10 of pVIc. In this work, pVIc formed a homodimer via disulfide bond formation with a second-order rate constant of 0.12 M-1 s(-1),and half of the homodimer could covalently bind to AVP via thiol-disulfide exchange. Alternatively, monomeric pVIc could form a disulfide bond with AVP via oxidation. Regardless ofthe mechanism by which AVP becomes covalently bound to pVIc. the kinetic constants for substrate hydrolysis were the same. The equilibrium dissociation constant. K-d. for the reversible binding of pVIc to AVP was 4.4 muM. The Ki for the binding of the mutant C10A-pVIc was at least 100-fold higher. Surprisingly, the Kd for the binding of the C10A-pVIc mutant to AVP decreased at least 60-fold, to 6.93 /iM, in the presence of 12mer ssDNA. Furthermore, once the mutant C10A-pVIc was bound to an AVP-DNA complex, the macroscopic kinetic constants for substrate hydrolysis were the same as those exhibited by wild-type pVIc. Although the cysteine in pVIc is important in the binding of pVIc to AVP, formation of a disulfide bond between pVIc and AVP was not required for maximal stimulation of enzyme activity by pVIc. C1 Brookhaven Natl Lab, Dept Biol, Upton, NY 11973 USA. SUNY Stony Brook, Dept Pharmacol Sci, Stony Brook, NY 11794 USA. RP Mangel, WF (reprint author), Brookhaven Natl Lab, Dept Biol, Upton, NY 11973 USA. FU NIAID NIH HHS [AI41599] NR 24 TC 16 Z9 17 U1 1 U2 3 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 4 PY 2001 VL 40 IS 48 BP 14468 EP 14474 DI 10.1021/bi011562d PG 7 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 497PR UT WOS:000172465100018 PM 11724559 ER PT J AU Kleiger, G Perry, J Eisenberg, D AF Kleiger, G Perry, J Eisenberg, D TI 3D structure and significance of the G Phi XXG helix packing motif in tetramers of the E1 beta subunit of pyruvate dehydrogenase from the archeon Pyrobaculum aerophilum SO BIOCHEMISTRY LA English DT Article ID ALPHA-KETOACID DEHYDROGENASE; SYRUP-URINE-DISEASE; CRYSTAL-STRUCTURE; ESCHERICHIA-COLI; HETERODIMERIC INTERMEDIATE; MULTIENZYME COMPLEX; GXXXG MOTIF; ALPHA(2)BETA(2); GROEL/GROES; ASSOCIATION AB As part Of a Structural genomics project, we have determined the 2.0 Angstrom structure of the E1 beta subunit of pyruvate dehydrogenase from Pyrobaculum aerophilum (PA), a thermophilic archaeon. The overall fold of E1 beta from PA is closely similar to the previously determined E1 beta structures from humans (HU) and P. putida (PP). However, unlike the HU and PP structures, the PA structure was determined in the absence of its partner subunit, E1 alpha. Significant structural rearrangements occur in E1 beta when its E1 alpha partner is absent, including rearrangement of several secondary Structure elements such as helix C. Helix C is buried by E1 alpha in the HU and PP structures, but makes crystal contacts in the PA structure that lead to an apparent beta (4) tetramer. Static light scattering and sedimentation velocity data are consistent with the formation of PA E1 beta tetramers in solution. The interaction or helix C with its symmetry-related counterpart stabilizes the tetrameric interface, where two glycine residues on the same race of one helix create a packing surface for the other helix. This G Phi XXG helix-helix interaction motif has previously been found in interacting transmembrane helices, and is round here at the E1 alpha -E1 beta interface for both the HU and PP alpha (2)beta (2) tetramers. As a case study in structural genomics, this work illustrates that comparative analysis of protein structures can identify the structural significance of a sequence motif. C1 Univ Calif Los Angeles, Howard Hughes Med Inst, DOE Lab Struct Biol & Mol Med, Inst Mol Biol, Los Angeles, CA 90095 USA. RP Eisenberg, D (reprint author), Univ Calif Los Angeles, Howard Hughes Med Inst, DOE Lab Struct Biol & Mol Med, Inst Mol Biol, Box 951570, Los Angeles, CA 90095 USA. FU NIGMS NIH HHS [GM07185] NR 29 TC 16 Z9 18 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 4 PY 2001 VL 40 IS 48 BP 14484 EP 14492 DI 10.1021/bi011016k PG 9 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 497PR UT WOS:000172465100020 PM 11724561 ER PT J AU Malone, EL Rayner, S AF Malone, EL Rayner, S TI Role of the research standpoint in integrating global-scale and local-scale research SO CLIMATE RESEARCH LA English DT Article DE interdisciplinary research; global-local links; social sciences AB Climate change research is hampered by the gap between 2 styles of research, raising fundamental issues of standpoint, Interpretive-style researchers see themselves as at the center of the environment, experiencing it from within; their involvement is what allows them to gain knowledge. Descriptive-style researchers see themselves as outside the environment they analyze; their distance is what allows them to gain knowledge, This fundamental difference in standpoint indicates that attempts to meld the 2 styles of research in articulating global-local links are unrealistic and doomed to failure. Instead, we should look for complementarities and attempt to bring the differently achieved knowledge to bear on global problems. C1 Pacific NW Natl Lab, Washington, DC 20024 USA. Columbia Univ, Sch Int & Publ Affairs, New York, NY 10027 USA. RP Malone, EL (reprint author), Pacific NW Natl Lab, 901 D St,Suite 900, Washington, DC 20024 USA. NR 12 TC 16 Z9 16 U1 0 U2 7 PU INTER-RESEARCH PI OLDENDORF LUHE PA NORDBUNTE 23, D-21385 OLDENDORF LUHE, GERMANY SN 0936-577X J9 CLIMATE RES JI Clim. Res. PD DEC 4 PY 2001 VL 19 IS 2 BP 173 EP 178 DI 10.3354/cr019173 PG 6 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA 521BZ UT WOS:000173820000008 ER PT J AU Hahn, H Lee, JH Balsara, NP Garetz, BA Watanabe, H AF Hahn, H Lee, JH Balsara, NP Garetz, BA Watanabe, H TI Viscoelastic properties of aligned block copolymer lamellae SO MACROMOLECULES LA English DT Article ID TO-DISORDER TRANSITION; SMECTIC LIQUID-CRYSTALS; DIBLOCK COPOLYMER; SHEAR-FLOW; POLYSTYRENE-POLYISOPRENE; MICROPHASE SEPARATION; MECHANICAL-PROPERTIES; ALIGNMENT; ORIENTATION; RHEOLOGY AB Structure-property relationships of aligned block copolymer lamellae in the vicinity of the order-disorder transition are studied by a combination of optical birefringence and rheology. Minimizing defect density was a crucial part of our experiments. The organization of block copolymer chains into aligned lamellae leads to a reduction in both zero shear viscosity and compliance relative to the disordered state. The frequency dependencies of the storage and loss shear moduli of the aligned lamellae are close to the Rouse prediction. In addition, the measured value of the compliance of the ordered and aligned state is within a factor of 2 of the Rouse prediction (agreement obtained with no adjustable parameters). In contrast, large differences between the experiments and the Rouse model are seen in the disordered state due to the presence of concentration fluctuations. C1 Univ Calif Berkeley, Dept Chem Engn, Berkeley, CA 94720 USA. Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Polytech Univ, Dept Chem Engn & Chem, Metrotech Ctr 6, Brooklyn, NY 11201 USA. Kyoto Univ, Inst Chem Res, Uji, Kyoto 611, Japan. RP Watanabe, H (reprint author), Univ Calif Berkeley, Dept Chem Engn, Berkeley, CA 94720 USA. NR 55 TC 15 Z9 15 U1 0 U2 10 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0024-9297 J9 MACROMOLECULES JI Macromolecules PD DEC 4 PY 2001 VL 34 IS 25 BP 8701 EP 8709 DI 10.1021/ma0109929 PG 9 WC Polymer Science SC Polymer Science GA 496TY UT WOS:000172414100020 ER PT J AU Glimm, J Li, XL Liu, YJ Zhao, N AF Glimm, J Li, XL Liu, YJ Zhao, N TI Conservative front tracking and level set algorithms SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article ID INTERFACE; COMPUTATION; FLOWS AB Hyperbolic conservation laws are foundational for many branches of continuum physics. Discontinuities in the solutions of these partial differential equations are widely recognized as a primary difficulty for numerical simulation, especially for thermal and shear discontinuities and fluid-fluid internal boundaries. We propose numerical algorithms that will (i) track these discontinuities as sharp internal boundaries, (ii) fully conserve the conserved quantities at a discrete level, even at the discontinuities, and (iii) display one order of numerical accuracy higher globally (at the discontinuity) than algorithms in common use. A significant improvement in simulation capabilities is anticipated through use of the proposed algorithms. C1 SUNY Stony Brook, Dept Appl Math & Stat, Stony Brook, NY 11794 USA. Brookhaven Natl Lab, Ctr Data Intens Comp, Upton, NY 11973 USA. Nanjing Univ Aeronaut & Astronaut, Dept Aerodynam, Nanjing 210016, Peoples R China. RP Glimm, J (reprint author), SUNY Stony Brook, Dept Appl Math & Stat, Stony Brook, NY 11794 USA. NR 9 TC 44 Z9 48 U1 0 U2 10 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 4 PY 2001 VL 98 IS 25 BP 14198 EP 14201 DI 10.1073/pnas.251420998 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 499NH UT WOS:000172576900005 PM 11717403 ER PT J AU Chertkov, M Gabitov, I Moeser, J AF Chertkov, M Gabitov, I Moeser, J TI Pulse confinement in optical fibers with random dispersion SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article ID POLARIZATION DISPERSION; TRANSMISSION-SYSTEM; DYNAMIC EQUATION; SOLITONS; PERTURBATIONS AB Short-range correlated uniform noise in the dispersion coefficient, inherent in many types of optical fibers, broadens and eventually destroys all initially ultra-short pulses. However, under the constraint that the integral of the random component of the dispersion coefficient is set to zero (pinned), periodically or quasiperiodically along the fiber, the dynamics of the pulse propagation changes dramatically. For the case that randomness is present in addition to constant positive dispersion, the pinning restriction significantly reduces average pulse broadening. If the randomness is present in addition to piece-wise constant periodic dispersion with positive residual value, the pinning may even provide probability distributions of pulse parameters that are numerically indistinguishable from the statistically steady case. The pinning method can be used to both manufacture better fibers and upgrade existing fiber links. C1 Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Chertkov, M (reprint author), Los Alamos Natl Lab, Div Theoret, POB 1663, Los Alamos, NM 87545 USA. RI Chertkov, Michael/O-8828-2015 NR 24 TC 10 Z9 10 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 4 PY 2001 VL 98 IS 25 BP 14208 EP 14211 DI 10.1073/pnas.241494198 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 499NH UT WOS:000172576900007 PM 11717397 ER PT J AU Christian, AT Pattee, MS Attix, CM Reed, BE Sorensen, KJ Tucker, JD AF Christian, AT Pattee, MS Attix, CM Reed, BE Sorensen, KJ Tucker, JD TI Detection of DNA point mutations and mRNA expression levels by rolling circle amplification in individual cells SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article ID PADLOCK PROBES; ORIENTATION; SEQUENCES; FISH AB Rolling circle amplification has been useful for detecting point mutations in isolated nucleic acids, but its application in cytological preparations has been problematic. By pretreating cells with a combination of restriction enzymes and exonucleases, we demonstrate that rolling circle amplification in situ can detect gene copy number and single base mutations in fixed cells with efficiencies up to 90%. It can also detect and quantify transcribed RNA in individual cells, making it a versatile tool for cell-based assays. C1 Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, Livermore, CA 94551 USA. RP Christian, AT (reprint author), Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, POB 5508, Livermore, CA 94551 USA. FU NCI NIH HHS [CA55861, P01 CA055861] NR 13 TC 62 Z9 70 U1 2 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 4 PY 2001 VL 98 IS 25 BP 14238 EP 14243 DI 10.1073/pnas.251383598 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 499NH UT WOS:000172576900013 PM 11724932 ER PT J AU Margolis, SB Baer, MR AF Margolis, SB Baer, MR TI A singular-perturbation analysis of the burning-rate eigenvalue for a two-temperature model of deflagrations in confined porous energetic materials SO SIAM JOURNAL ON APPLIED MATHEMATICS LA English DT Article DE deflagration; two-phase flow; confinement; energetic material; matched asymptotic expansions; singular perturbation; asymptotics beyond all orders ID 2-PHASE FLOW; GAS PERMEATION AB Deflagrations in porous energetic materials are characterized by regions of two-phase flow, where, for sufficiently large flow velocities, temperature-nonequilibration effects can significantly affect the overall burning rate. In the present work, we analyze a two-temperature model of deflagrations in confined porous propellants that exhibit a bubbling melt layer at their surfaces. For appropriately scaled rates of interphase heat transfer, the problem reduces to a nontrivial eigenvalue calculation in the thin reaction region where final conversion of the liquid to gaseous products occurs. For realistically small values of the gas-to-liquid thermal-conductivity ratio, solutions in the reaction zone take on a singular-perturbation character that can be exploited to derive an asymptotic expansion of the burning-rate eigenvalue. The resulting problem requires a rather sophisticated application of techniques in matched asymptotic expansions (asymptotics beyond all orders) stemming from the appearance of an infinite number of logarithmic terms in the asymptotic development that must be summed to arrive at the desired level of approximation. The physical effects of temperature nonequilibrium, which decreases the rate of heat transfer from the reacting liquid phase to the gas-phase products and thus allows a greater amount of thermal energy to remain in the reacting phase, are to increase the burning rate relative to the single-temperature limit and to sharpen the transition from conductive to convective burning. C1 Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA. Sandia Natl Labs, Engn Sci Ctr, Albuquerque, NM 87185 USA. RP Margolis, SB (reprint author), Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA. NR 13 TC 8 Z9 9 U1 0 U2 2 PU SIAM PUBLICATIONS PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 USA SN 0036-1399 J9 SIAM J APPL MATH JI SIAM J. Appl. Math. PD DEC 4 PY 2001 VL 62 IS 2 BP 627 EP 663 DI 10.1137/S0036139900377780 PG 37 WC Mathematics, Applied SC Mathematics GA 508XL UT WOS:000173115000013 ER PT J AU Babu, SS Miller, MK Vitek, JM David, SA AF Babu, SS Miller, MK Vitek, JM David, SA TI Characterization of the microstructure evolution in a nickel base superalloy during continuous cooling conditions SO ACTA MATERIALIA LA English DT Article DE welding; transmission electron microscopy (TEM); atom probe; nickel base superalloys ID COMPUTER-SIMULATION; ATOM-PROBE; PRECIPITATION; AL; ALLOYS; PHASE; MODEL AB The solidification characteristics of the gamma -phase from the liquid and the subsequent decomposition of the gamma phase control the evolution of the microstructure in nickel-base superalloy welds. The precipitation of the gamma phase from the gamma phase during continuous cooling conditions (0.17-75 K s(-1)) from the solutionizing temperature was characterized in a directionally solidified CM247DS alloy with thermomechanical simulator, and by transmission electron microscopy, atom probe field ion microscopy and atom probe tomography. The number density increased; size decreased and morphology of the gamma precipitates changed with an increase in cooling rate. Under rapid water-quenched conditions. complex partitioning of the alloying elements between gamma and gamma phases was observed, Atom probe tomography on samples subjected to slower cooling rates showed different partitioning behavior compared to that of water-quenched samples and the presence of secondary gamma precipitates in the samples subjected to a cooling rate of 1 K s(-1). Published by Elsevier Science Ltd on behalf of Acta Materialia Inc. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Babu, SS (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RI Babu, Sudarsanam/D-1694-2010 OI Babu, Sudarsanam/0000-0002-3531-2579 NR 29 TC 57 Z9 58 U1 4 U2 37 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 3 PY 2001 VL 49 IS 20 BP 4149 EP 4160 DI 10.1016/S1359-6454(01)00314-7 PG 12 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 497BR UT WOS:000172433300001 ER PT J AU Gabrisch, H Kjeldgaard, L Johnson, E Dahmen, U AF Gabrisch, H Kjeldgaard, L Johnson, E Dahmen, U TI Equilibrium shape and interface roughening of small liquid Pb inclusions in solid Al SO ACTA MATERIALIA LA English DT Article DE interface; phase transformations; aluminium alloys; equilibrium shape; transmission electron microscopy (TEM) ID CRITICAL-BEHAVIOR; LEAD INCLUSIONS; ALUMINUM; SOLIDIFICATION; CRYSTALS; MATRIX AB The shape of liquid Pb inclusions embedded in a solid At matrix was investigated at temperatures between 300 and 500 degreesC using in-situ electron microscopy. Inclusion shapes in the size rang, from a few nanometers to about 150 nm were found to depend on size, temperature and thermal history. During isothermal annealing after melting, small inclusions rounded off while larger inclusions remained faceted until the temperature was raised to about 500 degreesC. During subsequent cooling, inclusions refaceted, although less strongly than during heating. The shape hysteresis between heating and cooling cycles was found to be due to the barrier of ledge nucleation necessary to advance the faceted interfaces. It is shown that this kinetic barrier can explain the observed dependence on size and temperature, and that the (111) interface undergoes a roughening transition at about 550 degreesC. Even under conditions of kinetic limitation it was possible to measure local equilibrium by modeling kinetically limited inclusions as a droplet in a crevice. For this type of measurement, the hysteresis between heating and cooling cycles disappeared, and the true equilibrium shape could be derived. The anisotropy of interfacial energy was shown to be significantly smaller than previously reported, and at about 2%, similar to the anisotropy of the surface energy for fcc metals, From the width of facets on the equilibrium shape, the step energy was determined to be epsilon = 1.9(.)10(-11) J/m at 350 degreesC. Published by Elsevier Science Ltd on behalf of Acta Materialia Inc. C1 Lawrence Berkeley Lab, Natl Ctr Electron Microscopy, Berkeley, CA 94720 USA. Univ Copenhagen, Niels Bohr Inst, Orsted Lab, DK-2100 Copenhagen, Denmark. RP Lawrence Berkeley Lab, Natl Ctr Electron Microscopy, 1 Cyclotron Rd, Berkeley, CA 94720 USA. EM udahmen@lbl.gov RI Gabrisch, Heike/I-5021-2013 NR 37 TC 61 Z9 61 U1 0 U2 21 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1359-6454 EI 1873-2453 J9 ACTA MATER JI Acta Mater. PD DEC 3 PY 2001 VL 49 IS 20 BP 4259 EP 4269 DI 10.1016/S1359-6454(01)00307-X PG 11 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 497BR UT WOS:000172433300012 ER PT J AU Liu, S Napolitano, RE Trivedi, R AF Liu, S Napolitano, RE Trivedi, R TI Measurement of anisotropy of crystal-melt interfacial energy for a binary Al-Cu alloy SO ACTA MATERIALIA LA English DT Article DE interface; microstructure; aluminium alloys; anisotropy ID DENDRITIC GROWTH; SURFACE-TENSION; SOLIDIFICATION; INSTABILITIES; MORPHOLOGY; KINETICS AB The anisotropy of solid-liquid interfacial energy for an Al-4.0 wt% Cu alloy is determined through measurement of equilibrium shape. Measurements are performed using a fine dispersion of liquid particles entrained within a single-crystal single-phase solid. Specimens are sectioned normal to the (100) direction in the continuous phase, and the droplets are observed to exhibit four-fold symmetry on this plane. The radial variation on this plane is measured using optical and chemical techniques, and the normalized anisotropy parameter is determined to be 0.98%. Equilibrium conditions are validated, and quench effects are investigated using microchemical analysis techniques. (C) 2001 Acta Materialia Inc. Published by Elsevier Science Ltd, All rights reserved. C1 Iowa State Univ, Ames Lab, US DOE, Dept Mat Sci & Engn, Ames, IA 50011 USA. RP Trivedi, R (reprint author), Iowa State Univ, Ames Lab, US DOE, Dept Mat Sci & Engn, Ames, IA 50011 USA. NR 21 TC 65 Z9 68 U1 1 U2 28 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 3 PY 2001 VL 49 IS 20 BP 4271 EP 4276 DI 10.1016/S1359-6454(01)00306-8 PG 6 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 497BR UT WOS:000172433300013 ER PT J AU Agnew, SR Yoo, MH Tome, CN AF Agnew, SR Yoo, MH Tome, CN TI Application of texture simulation to understanding mechanical behavior of Mg and solid solution alloys containing Li or Y SO ACTA MATERIALIA LA English DT Article DE texture; dislocations; magnesium; mechanical properties; plastic; constitutive equations ID HEXAGONAL SYMMETRY; ZIRCONIUM ALLOYS; PRISMATIC GLIDE; DEFORMATION; MAGNESIUM; POLYCRYSTALS; EVOLUTION; TITANIUM; INSITU; SLIP AB The viscoplastic self-consistent model was used to interpret differences in the mechanical behavior of hexagonal close packed magnesium alloys. There are only subtle differences in the compression textures of magnesium and its solid solution alloys containing lithium or yttrium. However, the plane strain compression textures of the alloys showed an increasing tendency for the basal poles to rotate away from the "normal direction" towards the "rolling direction". Texture simulations enabled these distinctions to be attributed to the increased activity of the non-basal (c + a) slip mode. The alloys had improved compressive ductilities compared to pure magnesium, and the increased c + a slip mode activity provides a satisfying explanation for this improvement, since it can accommodate c-axis compression within individual grains. Accounting for individual deformation mode hardening enabled the flow curves to be simulated and the anisotropic plastic response of textured wrought alloys to be mechanistically understood and predicted. (C) 2001 Acta Materialia Inc. Published by Elsevier Science Ltd. All rights reserved. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. RP Agnew, SR (reprint author), Univ Virginia, Dept Mat Sci & Engn, Charlottesville, VA 22904 USA. RI Tome, Carlos/D-5058-2013 NR 40 TC 692 Z9 736 U1 21 U2 179 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 3 PY 2001 VL 49 IS 20 BP 4277 EP 4289 DI 10.1016/S1359-6454(01)00297-X PG 13 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 497BR UT WOS:000172433300014 ER PT J AU Horstemeyer, MF Baskes, MI Plimpton, SJ AF Horstemeyer, MF Baskes, MI Plimpton, SJ TI Length scale and time scale effects on the plastic flow of fcc metals SO ACTA MATERIALIA LA English DT Article DE plastic flow; fcc metals ID EMBEDDED-ATOM METHOD; STRAIN GRADIENT PLASTICITY; MOLECULAR-DYNAMICS; LATTICE-DEFECTS; NICKEL; INDENTATION; HYDROGEN; SIMULATIONS; DEFORMATION; SURFACES AB We examine size scale and strain rate effects on single-crystal face-centered cubic (fee) metals. To study yield and work hardening, we per-form simple shear molecular dynamics simulations using the embedded atom method (EAM) on single-crystal nickel ranging from 100 atoms to 100 million atoms and at strain rate., ranging from 10(7) to 10(12) s(-1). We compare our atomistic simulation results with experimental data obtained from interfacial force microscopy (IFM). nano-indentation, micro-indentation and small-scale torsion. The data are found to scale with a geometric length scale parameter defined by the ratio of volume to surface area of the samples. The atomistic simulations reveal that dislocations nucleating at free surfaces are critical to causing micro-yield and macro-yield in pristine material. The increase of flow stress at increasing strain rates results from phonon drag, and a simple model is developed to demonstrate this effect. Another important aspect of this study reveals that plasticity as reflected by the global averaged stress-strain behavior is characterized by four different length scales: (1) below 10(4) atoms, (2) between 10(4) and 10(6) atoms (2 mum), (3) between 2 mum and 300 mum, and (4) above 300 mum. (C) 2001 Acta Materialia Inc. published by Elsevier Science Ltd. All rights reserved. C1 Sandia Natl Labs, Ctr Mat Sci & Engn, Livermore, CA 94551 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Sandia Natl Labs, Ctr Computat Comp & Math, Albuquerque, NM 87185 USA. RP Horstemeyer, MF (reprint author), Sandia Natl Labs, Ctr Mat Sci & Engn, Livermore, CA 94551 USA. OI Horstemeyer, Mark/0000-0003-4230-0063 NR 41 TC 205 Z9 209 U1 2 U2 75 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 3 PY 2001 VL 49 IS 20 BP 4363 EP 4374 DI 10.1016/S1359-6454(01)00149-5 PG 12 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 497BR UT WOS:000172433300021 ER PT J AU Yu, CT Li, DQ Pearson, J Bader, SD AF Yu, CT Li, DQ Pearson, J Bader, SD TI Alignment of self-assembled magnetic nanostructures: Co dot chains and stripes on grooved Ru(0001) SO APPLIED PHYSICS LETTERS LA English DT Article ID GE ISLANDS; NANOCRYSTAL SUPERLATTICES; VICINAL SURFACES; GROWTH; DIFFUSION; SI(001); CRYSTAL; FLAT AB We have deposited 0-60 nm Co with a wedge-shaped thickness gradient onto a grooved Ru(0001) substrate by means of molecular-beam epitaxy at 350 degreesC. The resultant epitaxial Co island (dot) structure was characterized ex situ using atomic- and magnetic-force microscopy and the magneto-optic Kerr effect. The dots self-assemble with similar to 70-500 nm diameter, similar to1-7 nm height, and align into linear chains along the grooves with spacings in the chains to decrease from similar to1 mum until they form continuous stripes, depending on dosage and groove structure. The dots have magnetic single domains with in-plane easy axes. (C) 2001 American Institute of Physics. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Li, DQ (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Bader, Samuel/A-2995-2013 NR 20 TC 23 Z9 24 U1 1 U2 3 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD DEC 3 PY 2001 VL 79 IS 23 BP 3848 EP 3850 DI 10.1063/1.1421624 PG 3 WC Physics, Applied SC Physics GA 495WC UT WOS:000172362500034 ER PT J AU Tour, JM Rawlett, AM Kozaki, M Yao, YX Jagessar, RC Dirk, SM Price, DW Reed, MA Zhou, CW Chen, J Wang, WY Campbell, I AF Tour, JM Rawlett, AM Kozaki, M Yao, YX Jagessar, RC Dirk, SM Price, DW Reed, MA Zhou, CW Chen, J Wang, WY Campbell, I TI Synthesis and preliminary testing of molecular wires and devices SO CHEMISTRY-A EUROPEAN JOURNAL LA English DT Article DE cross-coupling; molecular devices; self-assembly ID SELF-ASSEMBLED MONOLAYERS; MULTIBIT INFORMATION-STORAGE; LIGHT-EMITTING-DIODES; ELECTRONIC DEVICES; ALLIGATOR CLIPS; ELECTRICAL RECTIFICATION; CONJUGATED POLYMERS; PORPHYRINS BEARING; THIOESTER TERMINI; SCALE ELECTRONICS AB Presented here are several convergent synthetic routes to conjugated oligo(phenylene ethynylene)s. Some of these oligomers are free of functional groups, while others possess donor groups, acceptor groups, porphyrin interiors, and other heterocyclic interiors for various potential transmission and digital device applications. The syntheses of oligo(phenylene ethynylene)s with a variety of end groups for attachment to numerous metal probes and surfaces are presented. Some of the functionalized molecular systems showed linear, wirelike, current versus voltage (I(V)) responses, while others exhibited nonlinear I(V) curves for negative differential resistance (NDR) and molecular random access memory effects. Finally, the go syntheses of functionalized oligomers are described that can form self-assembled monolayers on metallic electrodes that reduce the Schottky barriers. Information from the Schottky barrier studies can provide useful insight into molecular alligator clip optimizations for molecular electronics. C1 Rice Univ, Dept Chem, Houston, TX 77005 USA. Rice Univ, Ctr Nanoscale Sci & Technol, Houston, TX 77005 USA. Yale Univ, Dept Elect Engn, New Haven, CT 06520 USA. Yale Univ, Dept Appl Phys, New Haven, CT 06520 USA. Yale Univ, Dept Phys, New Haven, CT 06520 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Tour, JM (reprint author), Rice Univ, Dept Chem, MS 222,6100 Main St, Houston, TX 77005 USA. EM tour@rice.edu; mark.reed@yale.edu; campbell@ianl.gov RI Zhou, Chongwu/F-7483-2010; OI Tour, James/0000-0002-8479-9328 NR 83 TC 227 Z9 227 U1 0 U2 19 PU WILEY-V C H VERLAG GMBH PI BERLIN PA PO BOX 10 11 61, D-69451 BERLIN, GERMANY SN 0947-6539 J9 CHEM-EUR J JI Chem.-Eur. J. PD DEC 3 PY 2001 VL 7 IS 23 BP 5118 EP 5134 DI 10.1002/1521-3765(20011203)7:23<5118::AID-CHEM5118>3.0.CO;2-1 PG 17 WC Chemistry, Multidisciplinary SC Chemistry GA 499ZA UT WOS:000172599900014 PM 11775685 ER PT J AU Franzen, S Miskowski, VM Shreve, AP Wallace-Williams, SE Woodruff, WH Ondrias, MR Barr, ME Moore, L Boxer, SG AF Franzen, S Miskowski, VM Shreve, AP Wallace-Williams, SE Woodruff, WH Ondrias, MR Barr, ME Moore, L Boxer, SG TI Electrostatic and conformational effects on the electronic structures of distortional isomers of a mixed-valence binuclear Cu complex SO INORGANIC CHEMISTRY LA English DT Article ID TRANSITION-METAL COMPLEXES; RAMAN-SPECTROSCOPY; A SITE; OXIDASE; ABSORPTION; CHEMISTRY; FORMS AB The electronic structure of the binuclear copper complex [Cu-2(L)](3+) [L = N(CH2CH2N(H)CH2CH2N(H)CH2CH2)(3)N] has been investigated by resonance Raman and electroabsorption spectroscopy. Crystallographic Cu-2 distances of 2.364(1) and 2.415(1) A determined for the nitrate and acetate salts, respectively, are consistent with a substantial metal-metal interaction. The Cu-Cu bonding interaction in the binuclear complex is modulated both in the solid state and in solution by the ligand environment through coupling to ligand torsional modes that are, in turn, stabilized by hydrogen bonding. Electroabsorption data on the three major visible and near-infrared electronic transitions Of Cu2L, lambda (max) (epsilon (max)) = 1000 nm (similar to 1200 M-1 cm(-1)), 748 nm (5600 M-1 cm(-1)), and 622 nm (3350 M-1 cm(-1).), reveal a difference dipole moment between the ground and excited states (Delta mu (A)) because of symmetry breaking. The difference polarizability for all three of the transitions is negative, indicating that the ground state is more polarizable than the excited state. A general model to explain this behavior in terms of the proximity of accessible transitions involving copper d electrons is proposed to explain the larger polarizability of the ground state. Raman excitation profiles (REPs) provide evidence for multiple conformational states of [Cu-2(L)](3+). Separate REPs were obtained for each of the components of the two major Raman bands for nu (1) (a Cu-Cu stretching mode) and nu (2) (a Cu-Cu-N-eq bending mode). The Raman data along with quantum chemical ZINDO/S CI calculations provide evidence for isomeric forms of Cu2L with strong coupling between the conformation of L and the Cu-Cu bond length. C1 N Carolina State Univ, Dept Chem, Raleigh, NC 27695 USA. Los Alamos Natl Lab, Biosci & Nucl Mat & Technol Div, Los Alamos, NM 87545 USA. Univ New Mexico, Dept Chem, Albuquerque, NM 87131 USA. Stanford Univ, Dept Chem, Stanford, CA 94305 USA. RP Franzen, S (reprint author), N Carolina State Univ, Dept Chem, Box 8204, Raleigh, NC 27695 USA. NR 24 TC 15 Z9 15 U1 0 U2 9 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 3 PY 2001 VL 40 IS 25 BP 6375 EP 6382 DI 10.1021/ic010494g PG 8 WC Chemistry, Inorganic & Nuclear SC Chemistry GA 498DR UT WOS:000172495000006 PM 11720490 ER PT J AU Knebel, G Braithwaite, D Lapertot, G Canfield, PC Flouquet, J AF Knebel, G Braithwaite, D Lapertot, G Canfield, PC Flouquet, J TI Magnetically ordered Kondo lattice in YbNi2Ge2 at high pressure SO JOURNAL OF PHYSICS-CONDENSED MATTER LA English DT Article ID HEAVY-FERMION COMPOUNDS; ELECTRICAL-RESISTIVITY; SPIN FLUCTUATIONS; PHASE-TRANSITION; SUPERCONDUCTIVITY; SYSTEMS; TEMPERATURE; STATE; CECU6-XAUX; YBCU2SI2 AB We have studied the electrical resistivity of YbNi2Ge2 under hydrostatic pressure up to 100 kbar. With increasing pressure the system is continuously tuned from an intermediate valence state at low pressure to a magnetically ordered Kondo lattice at high pressure. The critical pressure for the appearance of a magnetic ground state is near 50 kbar. Below P-c the resistivity shows a T-2 dependence, characteristic of a Fermi liquid description at low temperatures. The coefficient of the T-2 term increases drastically on approaching P-c. Above P-c, the magnetic transition temperature T-m increases linearly with pressure. The magnetoresistance at high pressure suggests the importance of ferromagnetic coupling. C1 CEA Grenoble, Dept Rech Fondamentale Mat Condensee, SPSMS, F-38054 Grenoble, France. Iowa State Univ Sci & Technol, Dept Phys & Astron, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. RP Knebel, G (reprint author), CEA Grenoble, Dept Rech Fondamentale Mat Condensee, SPSMS, F-38054 Grenoble, France. RI LAPERTOT, Gerard/B-3354-2008; Knebel, Georg/A-3294-2012; Canfield, Paul/H-2698-2014 NR 52 TC 41 Z9 41 U1 0 U2 11 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 3 PY 2001 VL 13 IS 48 BP 10935 EP 10946 DI 10.1088/0953-8984/13/48/318 PG 12 WC Physics, Condensed Matter SC Physics GA 505YR UT WOS:000172943600024 ER PT J AU Abrikosov, AA AF Abrikosov, AA TI Superconductivity due to ferromagnetically ordered localized spins SO JOURNAL OF PHYSICS-CONDENSED MATTER LA English DT Letter AB A new mechanism of simultaneous appearance of ferromagnetism and superconductivity based on interaction of electrons mediated by localized spins was recently proposed by Suhl. Here the superconducting critical temperature is calculated for this model and conditions for appearance of superconductivity are analysed. It is shown that this mechanism can lead only to an s-wave order parameter. Superconductivity appears together with ferromagnetism but persists only until the ferromagnetism is weak. In order for it not to be destroyed by the paramagnetic effect, the metal has to be of a heavy-fermion type. This all fits recent experimental data obtained for UGe2. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Abrikosov, AA (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 12 TC 34 Z9 36 U1 1 U2 1 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 3 PY 2001 VL 13 IS 48 BP L943 EP L947 DI 10.1088/0953-8984/13/48/104 PG 5 WC Physics, Condensed Matter SC Physics GA 505YR UT WOS:000172943600004 ER PT J AU Kennedy, BJ Vogt, T Martin, CD Parise, JB Hriljac, JA AF Kennedy, BJ Vogt, T Martin, CD Parise, JB Hriljac, JA TI Pressure-induced orthorhombic to rhombohedral phase transition in LaGaO3 SO JOURNAL OF PHYSICS-CONDENSED MATTER LA English DT Letter ID POWDER NEUTRON-DIFFRACTION; HIGH-TEMPERATURE PHASES; PEROVSKITES; NATAO3 AB The influence of pressure on the crystal structure of LaGaO3 has been studied using synchrotron x-ray diffraction. At atmospheric pressure LaGaO3 has an orthorhombic structure in Pnma and undergoes a first-order phase transition to a rhombohedral structure near 2.5 GPa. The transition is reversible and the orthorhombic structure is recovered upon releasing the pressure below 2 GPa. C1 Univ Sydney, Sch Chem, Ctr Heavy Met Res, Sydney, NSW 2006, Australia. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. SUNY Stony Brook, Dept Geosci, Stony Brook, NY 11794 USA. Univ Birmingham, Sch Chem Sci, Birmingham B15 2TT, W Midlands, England. RP Kennedy, BJ (reprint author), Univ Sydney, Sch Chem, Ctr Heavy Met Res, Sydney, NSW 2006, Australia. RI Vogt, Thomas /A-1562-2011; OI Vogt, Thomas /0000-0002-4731-2787; Kennedy, Brendan/0000-0002-7187-4579 NR 23 TC 23 Z9 23 U1 0 U2 9 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 3 PY 2001 VL 13 IS 48 BP L925 EP L930 DI 10.1088/0953-8984/13/48/101 PG 6 WC Physics, Condensed Matter SC Physics GA 505YR UT WOS:000172943600001 ER PT J AU Lee, FX Mart, T Bennhold, C Haberzettl, H Wright, LE AF Lee, FX Mart, T Bennhold, C Haberzettl, H Wright, LE TI Quasifree kaon photoproduction on nuclei SO NUCLEAR PHYSICS A LA English DT Article ID PHOTOABSORPTION CROSS-SECTION; ELECTROMAGNETIC PRODUCTION; RESONANCE REGION; HYPERNUCLEAR PHOTOPRODUCTION; DIRAC PHENOMENOLOGY; PHOTON ENERGIES; SCATTERING; MODEL; STRANGENESS; PHYSICS AB Investigations of the quasifree reaction A(gamma, KY)B are presented in the distorted wave impulse approximation (DWIA). For this purpose, we present a revised tree-level model of elementary kaon photoproduction that incorporates hadronic form factors consistent with gauge invariance, uses SU(3) values for the Born couplings and uses resonances consistent with multichannel analyses. The potential of exclusive quasifree kaon photoproduction on nuclei to reveal details of the hyperon-nucleus interaction is examined. Detailed predictions for the coincidence cross section, the photon asymmetry, and the hyperon polarization and their sensitivities to the ingredients of the model are obtained for all six production channels. Under selected kinematics these observables are found to be sensitive to the hyperon-nucleus final-state interaction. Some polarization observables are found to be insensitive to distortion effects, making them ideal tools to search for possible medium modifications of the elementary amplitude. (C) 2001 Elsevier Science B.V. All rights reserved. C1 George Washington Univ, Dept Phys, Ctr Nucl Studies, Washington, DC 20052 USA. Jefferson Lab, Newport News, VA 23606 USA. Univ Indonesia, FMIPA, Depok 16424, Indonesia. Ohio Univ, Dept Phys & Astron, Inst Nucl & Particle Phys, Athens, OH 45701 USA. RP George Washington Univ, Dept Phys, Ctr Nucl Studies, Washington, DC 20052 USA. EM fxlee@gwu.edu OI Mart, Terry/0000-0003-4628-2245 NR 65 TC 63 Z9 64 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9474 EI 1873-1554 J9 NUCL PHYS A JI Nucl. Phys. A PD DEC 3 PY 2001 VL 695 BP 237 EP 272 DI 10.1016/S0375-9474(01)01098-3 PG 36 WC Physics, Nuclear SC Physics GA 489PU UT WOS:000172001000012 ER PT J AU Savage, MJ AF Savage, MJ TI Parity violation in low-energy np -> d gamma and the deuteron anapole moment SO NUCLEAR PHYSICS A LA English DT Article ID EFFECTIVE-FIELD-THEORY; ATOMIC CESIUM; FORM-FACTOR; STANDARD MODEL; NUCLEON; SCATTERING; NONCONSERVATION; (N)OVER-RIGHT-ARROW+P->D+GAMMA; ASYMMETRY; PIONS AB Parity violation in low-energy nuclear observables is included in the pionless effective field theory. The model-independent relation between the parity-violating asymmetry in (n) over right arrowp --> d gamma and the non-nucleon part of the deuteron anapole moment is discussed. The asymmetry in (n) over right arrowp d gamma computed with KSW power-counting, and recently criticized by Desplanques, is discussed. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Washington, Dept Phys, Seattle, WA 98195 USA. Jefferson Lab, Newport News, VA 23606 USA. RP Savage, MJ (reprint author), Univ Washington, Dept Phys, Seattle, WA 98195 USA. NR 54 TC 34 Z9 34 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 3 PY 2001 VL 695 BP 365 EP 373 DI 10.1016/S0375-9474(01)01105-8 PG 9 WC Physics, Nuclear SC Physics GA 489PU UT WOS:000172001000017 ER PT J AU Baltz, AJ Gelis, F McLerran, L Peshier, A AF Baltz, AJ Gelis, F McLerran, L Peshier, A TI Coulomb corrections to e(+)e(-) production in ultra-relativistic nuclear collisions SO NUCLEAR PHYSICS A LA English DT Article DE ultra-relativistic nuclei collisions; electromagnetic pair production; eikonal approximation; Coulomb corrections ID HEAVY-ION COLLISIONS; POSITRON PAIR PRODUCTION; HIGH-ENERGY LIMIT; FINITE-TEMPERATURE; REAL-TIME; GREEN-FUNCTIONS; DIRAC-EQUATION; FIXED TARGETS; FIELD-THEORY; SULFUR IONS AB The purpose of this paper is to explain the discrepancies existing in the literature relative to e(+)e(-) pair production in peripheral heavy ion collisions at ultra-relativistic energies. A controversial issue is the possible cancellation of Coulomb corrections to the Born term in the pair production cross-section. Such a cancellation has been observed in a recent approach based on finding retarded solutions of the Dirac equation, but does not seem to hold in a perturbative approach. We show in this paper that the two approaches are in fact calculating different observables: the perturbative approach gives the exclusive cross-section of single pair production, while the other method gives the inclusive cross-section. We have also performed a thorough study of the electron propagator in the non-static background field of the two nuclei, the conclusion of which is that the retarded propagator is in the ultrarelativistic limit a much simpler object than the Feynman propagator, and can be calculated exactly. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Gelis, F (reprint author), Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. NR 47 TC 54 Z9 54 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 3 PY 2001 VL 695 BP 395 EP 429 DI 10.1016/S0375-9474(01)01109-5 PG 35 WC Physics, Nuclear SC Physics GA 489PU UT WOS:000172001000019 ER PT J AU Abazov, VM Abbott, B Abdesselam, A Abolins, M Abramov, V Acharya, BS Adams, DL Adams, M Ahmed, SN Alexeev, GD Alves, GA Amos, N Anderson, EW Arnoud, Y Baarmand, MM Babintsev, VV Babukhadia, L Bacon, TC Baden, A Baldin, B Balm, PW Banerjee, S Barberis, E Baringer, P Barreto, J Bartlett, JF Bassler, U Bauer, D Bean, A Begel, M Belyaev, A Beri, SB Bernardi, G Bertram, I Besson, A Beuselinck, R Bezzubov, VA Bhat, PC Bhatnagar, V Bhattacharjee, M Blazey, G Blessing, S Boehnlein, A Bojko, NI Borcherding, D Bos, K Brandt, A Breedon, R Briskin, G Brock, R Brooijmans, G Bross, A Buchholz, D Buehler, M Buescher, V Burtovoi, VS Butler, JM Canelli, F Carvalho, W Casey, D Casilum, Z Castilla-Valdez, H Chakraborty, D Chan, KM Chekulaev, SV Cho, DK Choi, S Chopra, S Christenson, JH Chung, M Claes, D Clark, AR Cochran, J Coney, L Connolly, B Cooper, WE Coppage, D Crepe-Renaudin, S Cummings, MAC Cutts, D Davis, GA Davis, K De, K de Jong, SJ Del Signore, K Demarteau, M Demina, R Demine, P Denisov, D Denisov, SP Desai, S Diehl, HT Diesburg, M Di Loreto, G Doulas, S Draper, P Ducros, Y Dudko, LV Duensing, S Duflot, L Dugad, SR Duperrin, A Dyshkant, A Edmunds, D Ellison, J Elvira, VD Engelmann, R Eno, S Eppley, G Ermolov, P Eroshin, OV Estrada, J Evans, H Evdokimov, VN Fahland, T Feher, S Fein, D Ferbel, T Filthaut, F Fisk, HE Fisyak, Y Flattum, E Fleuret, F Fortner, M Fox, H Frame, KC Fu, S Fuess, S Gallas, E Galyaev, AN Gao, M Gavrilov, V Genik, RJ Genser, K Gerber, CE Gershtein, Y Gilmartin, R Ginter, G Gomez, B Gomez, G Goncharov, PI Solis, JLG Gordon, H Goss, LT Gounder, K Goussiou, A Graf, N Graham, G Grannis, PD Green, JA Greenlee, H Grinstein, S Groer, L Grunendahl, S Gupta, A Gurzhiev, SN Gutierrez, G Gutierrez, P Hadley, NJ Haggerty, H Hagopian, S Hagopian, V Hall, RE Hanlet, P Hansen, S Hauptman, JM Hays, C Hebert, C Hedin, D Heinmiller, JM Heinson, AP Heintz, U Heuring, T Hildreth, MD Hirosky, R Hobbs, JD Hoeneisen, B Huang, Y Illingworth, R Ito, AS Jaffre, M Jain, S Jesik, R Johns, K Johnson, M Jonckheere, A Jones, M Jostlein, H Juste, A Kahl, W Kahn, S Kajfasz, E Kalinin, AM Karmanov, D Karmgard, D Ke, Z Kehoe, R Khanov, A Kharchilava, A Kim, SK Klima, B Knuteson, B Ko, W Kohli, JM Kostritskiy, AV Kotcher, J Kothari, B Kotwal, AV Kozelov, AV Kozlovsky, EA Krane, J Krishnaswamy, MR Krivkova, P Krzywdzinski, S Kubantsev, M Kuleshov, S Kulik, Y Kunori, S Kupco, A Kuznetsov, VE Landsberg, G Lee, WM Leflat, A Leggett, C Lehner, F Li, J Li, QZ Li, X Lima, JGR Lincoln, D Linn, SL Linnemann, J Lipton, R Lucotte, A Lueking, L Lundstedt, C Luo, C Maciel, AKA Madaras, RJ Malyshev, VL Manankov, V Mao, HS Marshall, T Martin, MI Martin, RD Mauritz, KM May, B Mayorov, AA McCarthy, R McMahon, T Melanson, HL Merkin, M Merritt, KW Miao, C Miettinen, H Mihalcea, D Mishra, CS Mokhov, N Mondal, NK Montgomery, HE Moore, RW Mostafa, M da Motta, H Nagy, E Nang, F Narain, M Narasimham, VS Neal, HA Negret, JP Negroni, S Nunnemann, T O'Neil, D Oguri, V Olivier, B Oshima, N Padley, P Pan, LJ Papageorgiou, K Para, A Parashar, N Partridge, R Parua, N Paterno, M Patwa, A Pawlik, B Perkins, J Peters, M Peters, O Petroff, P Piegaia, R Pope, BG Popkov, E Prosper, HB Protopopescu, S Qian, J Raja, R Rajagopalan, S Ramberg, E Rapidis, PA Reay, NW Reucroft, S Ridel, M Rijssenbeek, M Rizatdinova, F Rockwell, T Roco, M Rubinov, P Ruchti, R Rutherfoord, J Sabirov, BM Sajot, G Santoro, A Sawyer, L Schamberger, RD Schellman, H Schwartzman, A Sen, N Shabalina, E Shivpuri, RK Shpakov, D Shupe, M Sidwell, RA Simak, V Singh, H Singh, JB Sirotenko, V Slattery, P Smith, E Smith, RP Snihur, R Snow, GR Snow, J Snyder, S Solomon, J Sorin, V Sosebee, M Sotnikova, N Soustruznik, K Souza, M Stanton, NR Steinbruck, G Stephens, RW Stichelbaut, F Stoker, D Stolin, V Stone, A Stoyanova, DA Strauss, M Strovink, M Stutte, L Sznajder, A Talby, M Taylor, W Tentindo-Repond, S Tripathi, SM Trippe, TG Turcot, AS Tuts, PM van Gemmeren, P Vaniev, V Van Kooten, R Varelas, N Vertogradov, LS Villeneuve-Seguier, F Volkov, AA Vorobiev, AP Wahl, HD Wang, H Wang, ZM Warchol, J Watts, G Wayne, M Weerts, H White, A White, JT Whiteson, D Wightman, JA Wijngaarden, DA Willis, S Wimpenny, SJ Womersley, J Wood, DR Yamada, R Yamin, P Yasuda, T Yatsunenko, YA Yip, K Youssef, S Yu, J Yu, Z Zanabria, M Zheng, H Zhou, Z Zielinski, M Zieminska, D Zieminski, A Zutshi, V Zverev, EG Zylberstejn, A AF Abazov, VM Abbott, B Abdesselam, A Abolins, M Abramov, V Acharya, BS Adams, DL Adams, M Ahmed, SN Alexeev, GD Alves, GA Amos, N Anderson, EW Arnoud, Y Baarmand, MM Babintsev, VV Babukhadia, L Bacon, TC Baden, A Baldin, B Balm, PW Banerjee, S Barberis, E Baringer, P Barreto, J Bartlett, JF Bassler, U Bauer, D Bean, A Begel, M Belyaev, A Beri, SB Bernardi, G Bertram, I Besson, A Beuselinck, R Bezzubov, VA Bhat, PC Bhatnagar, V Bhattacharjee, M Blazey, G Blessing, S Boehnlein, A Bojko, NI Borcherding, D Bos, K Brandt, A Breedon, R Briskin, G Brock, R Brooijmans, G Bross, A Buchholz, D Buehler, M Buescher, V Burtovoi, VS Butler, JM Canelli, F Carvalho, W Casey, D Casilum, Z Castilla-Valdez, H Chakraborty, D Chan, KM Chekulaev, SV Cho, DK Choi, S Chopra, S Christenson, JH Chung, M Claes, D Clark, AR Cochran, J Coney, L Connolly, B Cooper, WE Coppage, D Crepe-Renaudin, S Cummings, MAC Cutts, D Davis, GA Davis, K De, K de Jong, SJ Del Signore, K Demarteau, M Demina, R Demine, P Denisov, D Denisov, SP Desai, S Diehl, HT Diesburg, M Di Loreto, G Doulas, S Draper, P Ducros, Y Dudko, LV Duensing, S Duflot, L Dugad, SR Duperrin, A Dyshkant, A Edmunds, D Ellison, J Elvira, VD Engelmann, R Eno, S Eppley, G Ermolov, P Eroshin, OV Estrada, J Evans, H Evdokimov, VN Fahland, T Feher, S Fein, D Ferbel, T Filthaut, F Fisk, HE Fisyak, Y Flattum, E Fleuret, F Fortner, M Fox, H Frame, KC Fu, S Fuess, S Gallas, E Galyaev, AN Gao, M Gavrilov, V Genik, RJ Genser, K Gerber, CE Gershtein, Y Gilmartin, R Ginter, G Gomez, B Gomez, G Goncharov, PI Solis, JLG Gordon, H Goss, LT Gounder, K Goussiou, A Graf, N Graham, G Grannis, PD Green, JA Greenlee, H Grinstein, S Groer, L Grunendahl, S Gupta, A Gurzhiev, SN Gutierrez, G Gutierrez, P Hadley, NJ Haggerty, H Hagopian, S Hagopian, V Hall, RE Hanlet, P Hansen, S Hauptman, JM Hays, C Hebert, C Hedin, D Heinmiller, JM Heinson, AP Heintz, U Heuring, T Hildreth, MD Hirosky, R Hobbs, JD Hoeneisen, B Huang, Y Illingworth, R Ito, AS Jaffre, M Jain, S Jesik, R Johns, K Johnson, M Jonckheere, A Jones, M Jostlein, H Juste, A Kahl, W Kahn, S Kajfasz, E Kalinin, AM Karmanov, D Karmgard, D Ke, Z Kehoe, R Khanov, A Kharchilava, A Kim, SK Klima, B Knuteson, B Ko, W Kohli, JM Kostritskiy, AV Kotcher, J Kothari, B Kotwal, AV Kozelov, AV Kozlovsky, EA Krane, J Krishnaswamy, MR Krivkova, P Krzywdzinski, S Kubantsev, M Kuleshov, S Kulik, Y Kunori, S Kupco, A Kuznetsov, VE Landsberg, G Lee, WM Leflat, A Leggett, C Lehner, F Li, J Li, QZ Li, X Lima, JGR Lincoln, D Linn, SL Linnemann, J Lipton, R Lucotte, A Lueking, L Lundstedt, C Luo, C Maciel, AKA Madaras, RJ Malyshev, VL Manankov, V Mao, HS Marshall, T Martin, MI Martin, RD Mauritz, KM May, B Mayorov, AA McCarthy, R McMahon, T Melanson, HL Merkin, M Merritt, KW Miao, C Miettinen, H Mihalcea, D Mishra, CS Mokhov, N Mondal, NK Montgomery, HE Moore, RW Mostafa, M da Motta, H Nagy, E Nang, F Narain, M Narasimham, VS Neal, HA Negret, JP Negroni, S Nunnemann, T O'Neil, D Oguri, V Olivier, B Oshima, N Padley, P Pan, LJ Papageorgiou, K Para, A Parashar, N Partridge, R Parua, N Paterno, M Patwa, A Pawlik, B Perkins, J Peters, M Peters, O Petroff, P Piegaia, R Pope, BG Popkov, E Prosper, HB Protopopescu, S Qian, J Raja, R Rajagopalan, S Ramberg, E Rapidis, PA Reay, NW Reucroft, S Ridel, M Rijssenbeek, M Rizatdinova, F Rockwell, T Roco, M Rubinov, P Ruchti, R Rutherfoord, J Sabirov, BM Sajot, G Santoro, A Sawyer, L Schamberger, RD Schellman, H Schwartzman, A Sen, N Shabalina, E Shivpuri, RK Shpakov, D Shupe, M Sidwell, RA Simak, V Singh, H Singh, JB Sirotenko, V Slattery, P Smith, E Smith, RP Snihur, R Snow, GR Snow, J Snyder, S Solomon, J Sorin, V Sosebee, M Sotnikova, N Soustruznik, K Souza, M Stanton, NR Steinbruck, G Stephens, RW Stichelbaut, F Stoker, D Stolin, V Stone, A Stoyanova, DA Strauss, M Strovink, M Stutte, L Sznajder, A Talby, M Taylor, W Tentindo-Repond, S Tripathi, SM Trippe, TG Turcot, AS Tuts, PM van Gemmeren, P Vaniev, V Van Kooten, R Varelas, N Vertogradov, LS Villeneuve-Seguier, F Volkov, AA Vorobiev, AP Wahl, HD Wang, H Wang, ZM Warchol, J Watts, G Wayne, M Weerts, H White, A White, JT Whiteson, D Wightman, JA Wijngaarden, DA Willis, S Wimpenny, SJ Womersley, J Wood, DR Yamada, R Yamin, P Yasuda, T Yatsunenko, YA Yip, K Youssef, S Yu, J Yu, Z Zanabria, M Zheng, H Zhou, Z Zielinski, M Zieminska, D Zieminski, A Zutshi, V Zverev, EG Zylberstejn, A CA D0 Collaboration TI Search for new physics using QUAERO: A general interface to D0 event data SO PHYSICAL REVIEW LETTERS LA English DT Article ID COLLISIONS; COLLIDERS; JETS AB We describe QUAERO, a method that (i) enables the automatic optimization of searches for physics beyond the standard model, and (ii) provides a mechanism for making high energy collider data generally available. We apply QUAERO to searches for standard model WW, ZZ, and t (t) over bar production, to searches for these objects produced through a new heavy resonance, and to the first direct search for W' --> WZ. Through this interface, we make three data sets collected by the D0 experiment at roots = 1.8 TeV publicly available. C1 Joint Inst Nucl Res, Dubna, Russia. Univ Buenos Aires, Buenos Aires, DF, Argentina. Ctr Brasileiro Pesquisas Fis, LAFEX, Rio De Janeiro, Brazil. Univ Estado Rio de Janeiro, Rio De Janeiro, Brazil. Inst High Energy Phys, Beijing 100039, Peoples R China. Univ Los Andes, Bogota, Colombia. Charles Univ, Ctr Particle Phys, Prague, Czech Republic. Acad Sci Czech Republ, Inst Phys, Ctr Particle Phys, Prague, Czech Republic. Univ San Francisco, Quito, Ecuador. Univ Grenoble 1, Inst Sci Nucl, CNRS, IN2P3, Grenoble, France. Univ Mediterranee, CPPM, CNRS, IN2P3, Marseille, France. Lab Accelerateur Lineaire, CNRS, IN2P3, F-91405 Orsay, France. Univ Paris 06, LPNHE, CNRS, IN2P3, Paris, France. Univ Paris 07, LPNHE, CNRS, IN2P3, Paris, France. CEA, Serv Phys Particules, DAPNIA, Saclay, France. Univ Mainz, Inst Phys, D-6500 Mainz, Germany. Panjab Univ, Chandigarh 160014, India. Univ Delhi, Delhi 110007, India. Tata Inst Fundamental Res, Mumbai, India. Seoul Natl Univ, Seoul, South Korea. CINVESTAV, Mexico City 14000, DF, Mexico. FOM Inst NIKHEF, Amsterdam, Netherlands. Univ Amsterdam, NIKHEF, Amsterdam, Netherlands. Univ Nijmegen, NIKHEF, Nijmegen, Netherlands. Inst Nucl Phys, Krakow, Poland. Inst Theoret & Expt Phys, Moscow 117259, Russia. Moscow MV Lomonosov State Univ, Moscow, Russia. Inst High Energy Phys, Protvino, Russia. Univ Lancaster, Lancaster, England. Univ London Imperial Coll Sci Technol & Med, London, England. Univ Arizona, Tucson, AZ 85721 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Calif Davis, Davis, CA 95616 USA. Calif State Univ Fresno, Fresno, CA 93740 USA. Univ Calif Irvine, Irvine, CA 92697 USA. Univ Calif Riverside, Riverside, CA 92521 USA. Florida State Univ, Tallahassee, FL 32306 USA. Univ Hawaii, Honolulu, HI 96822 USA. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Illinois, Chicago, IL 60607 USA. No Illinois Univ, De Kalb, IL 60115 USA. Northwestern Univ, Evanston, IL 60208 USA. Indiana Univ, Bloomington, IN 47405 USA. Univ Notre Dame, Notre Dame, IN 46556 USA. Iowa State Univ, Ames, IA 50011 USA. Univ Kansas, Lawrence, KS 66045 USA. Kansas State Univ, Manhattan, KS 66506 USA. Louisiana Tech Univ, Ruston, LA 71272 USA. Univ Maryland, College Pk, MD 20742 USA. Boston Univ, Boston, MA 02215 USA. Northeastern Univ, Boston, MA 02115 USA. Univ Michigan, Ann Arbor, MI 48109 USA. Michigan State Univ, E Lansing, MI 48824 USA. Univ Nebraska, Lincoln, NE 68588 USA. Columbia Univ, New York, NY 10027 USA. Univ Rochester, Rochester, NY 14627 USA. SUNY Stony Brook, Stony Brook, NY 11794 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. Langston Univ, Langston, OK 73050 USA. Univ Oklahoma, Norman, OK 73019 USA. Brown Univ, Providence, RI 02912 USA. Univ Texas, Arlington, TX 76019 USA. Texas A&M Univ, College Stn, TX 77843 USA. Rice Univ, Houston, TX 77005 USA. Univ Virginia, Charlottesville, VA 22901 USA. Univ Washington, Seattle, WA 98195 USA. RP Abazov, VM (reprint author), Joint Inst Nucl Res, Dubna, Russia. RI Juste, Aurelio/I-2531-2015; Grinstein, Sebastian/N-3988-2014; Santoro, Alberto/E-7932-2014; Belyaev, Alexander/F-6637-2015; Kim, Sun Kee/G-2042-2015; Chekulaev, Sergey/O-1145-2015; Sznajder, Andre/L-1621-2016; Canelli, Florencia/O-9693-2016; Peters, Michael/B-4973-2009; Shivpuri, R K/A-5848-2010; Gutierrez, Phillip/C-1161-2011; Dudko, Lev/D-7127-2012; Leflat, Alexander/D-7284-2012; Merkin, Mikhail/D-6809-2012; Yip, Kin/D-6860-2013; Kuleshov, Sergey/D-9940-2013; De, Kaushik/N-1953-2013; Oguri, Vitor/B-5403-2013; Alves, Gilvan/C-4007-2013; OI Madaras, Ronald/0000-0001-7399-2993; Hedin, David/0000-0001-9984-215X; Wahl, Horst/0000-0002-1345-0401; Juste, Aurelio/0000-0002-1558-3291; Begel, Michael/0000-0002-1634-4399; de Jong, Sijbrand/0000-0002-3120-3367; Fisyak, Yuri/0000-0002-3151-8377; Landsberg, Greg/0000-0002-4184-9380; Blessing, Susan/0000-0002-4455-7279; Gershtein, Yuri/0000-0002-4871-5449; Duperrin, Arnaud/0000-0002-5789-9825; Hoeneisen, Bruce/0000-0002-6059-4256; Grinstein, Sebastian/0000-0002-6460-8694; Belyaev, Alexander/0000-0002-1733-4408; Kim, Sun Kee/0000-0002-0013-0775; Sznajder, Andre/0000-0001-6998-1108; Canelli, Florencia/0000-0001-6361-2117; Heinson, Ann/0000-0003-4209-6146; grannis, paul/0000-0003-4692-2142; Qian, Jianming/0000-0003-4813-8167; Sawyer, Lee/0000-0001-8295-0605; Strovink, Mark/0000-0001-7020-7769; Dudko, Lev/0000-0002-4462-3192; Yip, Kin/0000-0002-8576-4311; Kuleshov, Sergey/0000-0002-3065-326X; De, Kaushik/0000-0002-5647-4489; Blazey, Gerald/0000-0002-7435-5758; Evans, Harold/0000-0003-2183-3127; Beuselinck, Raymond/0000-0003-2613-7446; Hays, Chris/0000-0003-2371-9723; Bassler, Ursula/0000-0002-9041-3057; Filthaut, Frank/0000-0003-3338-2247 NR 17 TC 10 Z9 10 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 3 PY 2001 VL 87 IS 23 AR 231801 DI 10.1103/PhysRevLett.87.231801 PG 6 WC Physics, Multidisciplinary SC Physics GA 498ZZ UT WOS:000172545400011 PM 11736444 ER PT J AU Affolder, T Akimoto, H Akopian, A Albrow, MG Amaral, P Amidei, D Anikeev, K Antos, J Apollinari, G Arisawa, T Artikov, A Asakawa, T Ashmanskas, W Azfar, F Azzi-Bacchetta, P Bacchetta, N Bachacou, H Bailey, S de Barbaro, P Barbaro-Galtieri, A Barnes, VE Barnett, BA Baroiant, S Barone, M Bauer, G Bedeschi, F Belforte, S Bell, WH Bellettini, G Bellinger, J Benjamin, D Bensinger, J Beretvas, A Berge, JP Berryhill, J Bhatti, A Binkley, M Bisello, D Bishai, M Blair, RE Blocker, C Bloom, K Blumenfeld, B Blusk, SR Bocci, A Bodek, A Bokhari, W Bolla, G Bonushkin, Y Bortoletto, D Boudreau, J Brandl, A van den Brink, S Bromberg, C Brozovic, M Brubaker, E Bruner, N Buckley-Geer, E Budagov, J Budd, HS Burkett, K Busetto, G Byon-Wagner, A Byrum, KL Cabrera, S Calafiura, P Campbell, M Carithers, W Carlson, J Carlsmith, D Caskey, W Castro, A Cauz, D Cerri, A Chan, AW Chang, PS Chang, PT Chapman, J Chen, C Chen, YC Cheng, MT Chertok, M Chiarelli, G Chirikov-Zorin, I Chlachidze, G Chlebana, F Christofek, L Chu, ML Chung, YS Ciobanu, CI Clark, AG Connolly, A Conway, J Cordelli, M Cranshaw, J Cropp, R Culbertson, R Dagenhart, D D'Auria, S DeJongh, F Dell'Agnello, S Dell'Orso, M Demortier, L Deninno, M Derwent, PF Devlin, T Dittmann, JR Dominguez, A Donati, S Done, J D'Onofrio, M Dorigo, T Eddy, N Einsweiler, K Elias, JE Engels, E Erbacher, R Errede, D Errede, S Fan, Q Feild, RG Fernandez, JP Ferretti, C Field, RD Fiori, I Flaugher, B Foster, GW Franklin, M Freeman, J Friedman, J Fukui, Y Furic, I Galeotti, S Gallas, A Gallinaro, M Gao, T Garcia-Sciveres, M Garfinkel, AF Gatti, P Gay, C Gerdes, DW Giannetti, P Giromini, P Glagolev, V Glenzinski, D Gold, M Goldstein, J Gorelov, I Goshaw, AT Gotra, Y Goulianos, K Green, C Grim, G Gris, P Groer, L Grosso-Pilcher, C Guenther, M Guillian, G da Costa, JG Haas, RM Haber, C Hahn, SR Hall, C Handa, T Handler, R Hao, W Happacher, F Hara, K Hardman, AD Harris, RM Hartmann, F Hatakeyama, K Hauser, J Heinrich, J Heiss, A Herndon, M Hill, C Hoffman, KD Holck, C Hollebeek, R Holloway, L Hughes, R Huston, J Huth, J Ikeda, H Incandela, J Introzzi, G Iwai, J Iwata, Y James, E Jones, M Joshi, U Kambara, H Kamon, T Kaneko, T Karr, K Kasha, H Kato, Y Keaffaber, TA Kelley, K Kelly, M Kennedy, RD Kephart, R Khazins, D Kikuchi, T Kilminster, B Kim, BJ Kim, DH Kim, HS Kim, MJ Kim, SB Kim, SH Kim, YK Kirby, M Kirk, M Kirsch, L Klimenko, S Koehn, P Kondo, K Konigsberg, J Korn, A Korytov, A Kotwal, AV Kovacs, E Kroll, J Kruse, M Kuhlmann, SE Kurino, K Kuwabara, T Laasanen, AT Lai, N Lami, S Lammel, S Lancaster, J Lancaster, M Lander, R Lath, A Latino, G LeCompte, T Lee, AM Lee, K Leone, S Lewis, JD Lindgren, M Liss, TM Liu, JB Liu, YC Litvintsev, DO Lobban, O Lockyer, N Loken, J Loreti, M Lucchesi, D Lukens, P Lusin, S Lyons, L Lys, J Madrak, R Maeshima, K Maksimovic, P Malferrari, L Mangano, M Mariotti, M Martignon, G Martin, A Matthews, JAJ Mayer, J Mazzanti, P McFarland, KS McIntyre, P McKigney, E Menguzzato, M Menzione, A Mesropian, C Meyer, A Miao, T Miller, R Miller, JS Minato, H Miscetti, S Mishina, M Mitselmakher, G Moggi, N Moore, E Moore, R Morita, Y Moulik, T Mulhearn, M Mukherjee, A Muller, T Munar, A Murat, P Murgia, S Nachtman, J Nagaslaev, V Nahn, S Nakada, H Nakano, I Nelson, C Nelson, T Neu, C Neuberger, D Newman-Holmes, C Ngan, CYP Niu, H Nodulman, L Nomerotski, A Oh, SH Oh, YD Ohmoto, T Ohsugi, T Oishi, R Okusawa, T Olsen, J Orejudos, W Pagliarone, C Palmonari, F Paoletti, R Papadimitriou, V Partos, D Patrick, J Pauletta, G Paulini, M Paus, C Pellett, D Pescara, L Phillips, TJ Piacentino, G Pitts, KT Pompos, A Pondrom, L Pope, G Popovic, M Prokoshin, F Proudfoot, J Ptohos, F Pukhov, O Punzi, G Rakitine, A Ratnikov, F Reher, D Reichold, A Ribon, A Riegler, W Rimondi, F Ristori, L Riveline, M Robertson, WJ Robinson, A Rodrigo, T Rolli, S Rosenson, L Roser, R Rossin, R Rott, C Roy, A Ruiz, A Safonov, A St Denis, R Sakumoto, WK Saltzberg, D Sanchez, C Sansoni, A Santi, L Sato, H Savard, P Schlabach, P Schmidt, EE Schmidt, MP Schmitt, M Scodellaro, L Scott, A Scribano, A Segler, S Seidel, S Seiya, Y Semenov, A Semeria, F Shah, T Shapiro, MD Shepard, PF Shibayama, T Shimojima, M Shochet, M Sidoti, A Siegrist, J Sill, A Sinervo, P Singh, P Slaughter, AJ Sliwa, K Smith, C Snider, FD Solodsky, A Spalding, J Speer, T Sphicas, P Spinella, F Spiropulu, M Spiegel, L Steele, J Stefanini, A Strologas, J Strumia, F Stuart, D Sumorok, K Suzuki, T Takano, T Takashima, R Takikawa, K Tamburello, P Tanaka, M Tannenbaum, B Tecchio, M Tesarek, R Teng, PK Terashi, K Tether, S Thompson, AS Thurman-Keup, R Tipton, P Tkaczyk, S Toback, D Tollefson, K Tollestrup, A Tonelli, D Toyoda, H Trischuk, W de Troconiz, JF Tseng, J Turini, N Ukegawa, F Vaiciulis, T Valls, J Vejcik, S Velev, G Veramendi, G Vidal, R Vila, I Vilar, R Volobouev, I von der Mey, M Vucinic, D Wagner, RG Wagner, RL Wallace, NB Wan, Z Wang, C Wang, MJ Ward, B Waschke, S Watanabe, T Waters, D Watts, T Webb, R Wenzel, H Wester, WC Wicklund, AB Wicklund, E Wilkes, T Williams, HH Wilson, P Winer, BL Winn, D Wolbers, S Wolinski, D Wolinski, J Wolinski, S Worm, S Xu, X Wyss, J Yao, W Yeh, GP Yeh, P Yoh, J Yosef, C Yoshida, T Yu, I Yu, S Yu, Z Zanetti, A Zetti, F Zucchelli, S AF Affolder, T Akimoto, H Akopian, A Albrow, MG Amaral, P Amidei, D Anikeev, K Antos, J Apollinari, G Arisawa, T Artikov, A Asakawa, T Ashmanskas, W Azfar, F Azzi-Bacchetta, P Bacchetta, N Bachacou, H Bailey, S de Barbaro, P Barbaro-Galtieri, A Barnes, VE Barnett, BA Baroiant, S Barone, M Bauer, G Bedeschi, F Belforte, S Bell, WH Bellettini, G Bellinger, J Benjamin, D Bensinger, J Beretvas, A Berge, JP Berryhill, J Bhatti, A Binkley, M Bisello, D Bishai, M Blair, RE Blocker, C Bloom, K Blumenfeld, B Blusk, SR Bocci, A Bodek, A Bokhari, W Bolla, G Bonushkin, Y Bortoletto, D Boudreau, J Brandl, A van den Brink, S Bromberg, C Brozovic, M Brubaker, E Bruner, N Buckley-Geer, E Budagov, J Budd, HS Burkett, K Busetto, G Byon-Wagner, A Byrum, KL Cabrera, S Calafiura, P Campbell, M Carithers, W Carlson, J Carlsmith, D Caskey, W Castro, A Cauz, D Cerri, A Chan, AW Chang, PS Chang, PT Chapman, J Chen, C Chen, YC Cheng, MT Chertok, M Chiarelli, G Chirikov-Zorin, I Chlachidze, G Chlebana, F Christofek, L Chu, ML Chung, YS Ciobanu, CI Clark, AG Connolly, A Conway, J Cordelli, M Cranshaw, J Cropp, R Culbertson, R Dagenhart, D D'Auria, S DeJongh, F Dell'Agnello, S Dell'Orso, M Demortier, L Deninno, M Derwent, PF Devlin, T Dittmann, JR Dominguez, A Donati, S Done, J D'Onofrio, M Dorigo, T Eddy, N Einsweiler, K Elias, JE Engels, E Erbacher, R Errede, D Errede, S Fan, Q Feild, RG Fernandez, JP Ferretti, C Field, RD Fiori, I Flaugher, B Foster, GW Franklin, M Freeman, J Friedman, J Fukui, Y Furic, I Galeotti, S Gallas, A Gallinaro, M Gao, T Garcia-Sciveres, M Garfinkel, AF Gatti, P Gay, C Gerdes, DW Giannetti, P Giromini, P Glagolev, V Glenzinski, D Gold, M Goldstein, J Gorelov, I Goshaw, AT Gotra, Y Goulianos, K Green, C Grim, G Gris, P Groer, L Grosso-Pilcher, C Guenther, M Guillian, G da Costa, JG Haas, RM Haber, C Hahn, SR Hall, C Handa, T Handler, R Hao, W Happacher, F Hara, K Hardman, AD Harris, RM Hartmann, F Hatakeyama, K Hauser, J Heinrich, J Heiss, A Herndon, M Hill, C Hoffman, KD Holck, C Hollebeek, R Holloway, L Hughes, R Huston, J Huth, J Ikeda, H Incandela, J Introzzi, G Iwai, J Iwata, Y James, E Jones, M Joshi, U Kambara, H Kamon, T Kaneko, T Karr, K Kasha, H Kato, Y Keaffaber, TA Kelley, K Kelly, M Kennedy, RD Kephart, R Khazins, D Kikuchi, T Kilminster, B Kim, BJ Kim, DH Kim, HS Kim, MJ Kim, SB Kim, SH Kim, YK Kirby, M Kirk, M Kirsch, L Klimenko, S Koehn, P Kondo, K Konigsberg, J Korn, A Korytov, A Kotwal, AV Kovacs, E Kroll, J Kruse, M Kuhlmann, SE Kurino, K Kuwabara, T Laasanen, AT Lai, N Lami, S Lammel, S Lancaster, J Lancaster, M Lander, R Lath, A Latino, G LeCompte, T Lee, AM Lee, K Leone, S Lewis, JD Lindgren, M Liss, TM Liu, JB Liu, YC Litvintsev, DO Lobban, O Lockyer, N Loken, J Loreti, M Lucchesi, D Lukens, P Lusin, S Lyons, L Lys, J Madrak, R Maeshima, K Maksimovic, P Malferrari, L Mangano, M Mariotti, M Martignon, G Martin, A Matthews, JAJ Mayer, J Mazzanti, P McFarland, KS McIntyre, P McKigney, E Menguzzato, M Menzione, A Mesropian, C Meyer, A Miao, T Miller, R Miller, JS Minato, H Miscetti, S Mishina, M Mitselmakher, G Moggi, N Moore, E Moore, R Morita, Y Moulik, T Mulhearn, M Mukherjee, A Muller, T Munar, A Murat, P Murgia, S Nachtman, J Nagaslaev, V Nahn, S Nakada, H Nakano, I Nelson, C Nelson, T Neu, C Neuberger, D Newman-Holmes, C Ngan, CYP Niu, H Nodulman, L Nomerotski, A Oh, SH Oh, YD Ohmoto, T Ohsugi, T Oishi, R Okusawa, T Olsen, J Orejudos, W Pagliarone, C Palmonari, F Paoletti, R Papadimitriou, V Partos, D Patrick, J Pauletta, G Paulini, M Paus, C Pellett, D Pescara, L Phillips, TJ Piacentino, G Pitts, KT Pompos, A Pondrom, L Pope, G Popovic, M Prokoshin, F Proudfoot, J Ptohos, F Pukhov, O Punzi, G Rakitine, A Ratnikov, F Reher, D Reichold, A Ribon, A Riegler, W Rimondi, F Ristori, L Riveline, M Robertson, WJ Robinson, A Rodrigo, T Rolli, S Rosenson, L Roser, R Rossin, R Rott, C Roy, A Ruiz, A Safonov, A St Denis, R Sakumoto, WK Saltzberg, D Sanchez, C Sansoni, A Santi, L Sato, H Savard, P Schlabach, P Schmidt, EE Schmidt, MP Schmitt, M Scodellaro, L Scott, A Scribano, A Segler, S Seidel, S Seiya, Y Semenov, A Semeria, F Shah, T Shapiro, MD Shepard, PF Shibayama, T Shimojima, M Shochet, M Sidoti, A Siegrist, J Sill, A Sinervo, P Singh, P Slaughter, AJ Sliwa, K Smith, C Snider, FD Solodsky, A Spalding, J Speer, T Sphicas, P Spinella, F Spiropulu, M Spiegel, L Steele, J Stefanini, A Strologas, J Strumia, F Stuart, D Sumorok, K Suzuki, T Takano, T Takashima, R Takikawa, K Tamburello, P Tanaka, M Tannenbaum, B Tecchio, M Tesarek, R Teng, PK Terashi, K Tether, S Thompson, AS Thurman-Keup, R Tipton, P Tkaczyk, S Toback, D Tollefson, K Tollestrup, A Tonelli, D Toyoda, H Trischuk, W de Troconiz, JF Tseng, J Turini, N Ukegawa, F Vaiciulis, T Valls, J Vejcik, S Velev, G Veramendi, G Vidal, R Vila, I Vilar, R Volobouev, I von der Mey, M Vucinic, D Wagner, RG Wagner, RL Wallace, NB Wan, Z Wang, C Wang, MJ Ward, B Waschke, S Watanabe, T Waters, D Watts, T Webb, R Wenzel, H Wester, WC Wicklund, AB Wicklund, E Wilkes, T Williams, HH Wilson, P Winer, BL Winn, D Wolbers, S Wolinski, D Wolinski, J Wolinski, S Worm, S Xu, X Wyss, J Yao, W Yeh, GP Yeh, P Yoh, J Yosef, C Yoshida, T Yu, I Yu, S Yu, Z Zanetti, A Zetti, F Zucchelli, S CA CDF Collaborat TI Search for quark-lepton compositeness and a heavy W ' boson using the e nu channel in p(p)over-bar collisions at root s=1.8 TeV SO PHYSICAL REVIEW LETTERS LA English DT Article ID FERMION-PAIR PRODUCTION; SUPERCOLLIDER PHYSICS; CONTACT INTERACTIONS; DETECTOR; LIMITS; SCALES; CESIUM; BOUNDS; TESTS; MASS AB We present searches for quark-lepton compositeness and a heavy W' boson at high electron-neutrino transverse mass. We use similar to 110 pb(-1) of data collected in pp collisions at roots = 1.8 TeV by the CDF Collaboration during 1992-1995. The data are consistent with standard model expectations. Limits are set on the quark-lepton compositeness scale A, the ratio of partial cross sections sigma (W' --> e nu)/sigma (W --> e nu), and the mass of a W' boson with standard model couplings. We exclude Lambda < 2.81 TeV and a W' boson with mass below 754 GeV/c(2) at the 95% confidence level. Combining with our previously published limit obtained using the muon channel, we exclude a W' boson with mass below 786 GeV/c(2) at the 95% confidence level. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Acad Sinica, Inst Phys, Taipei 11529, Taiwan. 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 Davis, Davis, CA 95616 USA. Univ Calif Los Angeles, Los Angeles, CA 90024 USA. Univ Cantabria, CSIC, Inst Fis Cantabria, E-39005 Santander, Spain. Univ Chicago, Enrico Fermi Inst, Chicago, IL 60637 USA. Joint Inst Nucl Res, RU-141980 Dubna, Russia. 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. Univ Glasgow, Glasgow G12 8QQ, Lanark, Scotland. Harvard Univ, Cambridge, MA 02138 USA. Hiroshima Univ, Higashihiroshima 724, Japan. Univ Illinois, Urbana, IL 61801 USA. Johns Hopkins Univ, Baltimore, MD 21218 USA. Univ Karlsruhe, Inst Expt Kernphys, D-76128 Karlsruhe, Germany. Kyungpook Natl Univ, Ctr High Energy Phys, Taegu 702701, South Korea. Seoul Natl Univ, Seoul 151742, South Korea. Sungkyunkwan Univ, Suwon 440746, South Korea. High Energy Accelerator Res Org, Tsukuba, Ibaraki 305, Japan. 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 Oxford, Oxford OX1 3RH, England. Univ Padua, Ist Nazl Fis Nucl, Sez Padova, I-35131 Padua, Italy. Univ Penn, Philadelphia, PA 19104 USA. Ist Nazl Fis Nucl, I-56100 Pisa, Italy. Univ Pisa, 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. Texas A&M Univ, College Stn, TX 77843 USA. Texas Tech Univ, Lubbock, TX 79409 USA. Univ Toronto, Inst Particle Phys, Toronto, ON M5S 1A7, Canada. Univ Tsukuba, Tsukuba, Ibaraki 305, 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 Affolder, T (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RI Scodellaro, Luca/K-9091-2014; Lancaster, Mark/C-1693-2008; Vucinic, Dejan/C-2406-2008; Nomerotski, Andrei/A-5169-2010; Ruiz, Alberto/E-4473-2011; St.Denis, Richard/C-8997-2012; Azzi, Patrizia/H-5404-2012; Punzi, Giovanni/J-4947-2012; Chiarelli, Giorgio/E-8953-2012; Kim, Soo-Bong/B-7061-2014; Gallas Torreira, Abraham Antonio/K-6508-2014; Paulini, Manfred/N-7794-2014; vilar, rocio/P-8480-2014; Cabrera Urban, Susana/H-1376-2015; Introzzi, Gianluca/K-2497-2015; Gorelov, Igor/J-9010-2015; Prokoshin, Fedor/E-2795-2012; OI Scodellaro, Luca/0000-0002-4974-8330; Ruiz, Alberto/0000-0002-3639-0368; Azzi, Patrizia/0000-0002-3129-828X; Punzi, Giovanni/0000-0002-8346-9052; Chiarelli, Giorgio/0000-0001-9851-4816; Gallas Torreira, Abraham Antonio/0000-0002-2745-7954; Paulini, Manfred/0000-0002-6714-5787; Introzzi, Gianluca/0000-0002-1314-2580; Gorelov, Igor/0000-0001-5570-0133; Prokoshin, Fedor/0000-0001-6389-5399; Lami, Stefano/0000-0001-9492-0147; CHANG, PAO-TI/0000-0003-4064-388X; Signorelli, Giovanni/0000-0001-8262-8245; Goldstein, Joel/0000-0003-1591-6014 NR 27 TC 67 Z9 68 U1 2 U2 9 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 3 PY 2001 VL 87 IS 23 AR 231803 DI 10.1103/PhysRevLett.87.231803 PG 6 WC Physics, Multidisciplinary SC Physics GA 498ZZ UT WOS:000172545400013 PM 11736493 ER PT J AU Boaknin, E Hill, RW Proust, C Lupien, C Taillefer, L Canfield, PC AF Boaknin, E Hill, RW Proust, C Lupien, C Taillefer, L Canfield, PC TI Highly anisotropic gap function in borocarbide superconductor LuNi2B2C SO PHYSICAL REVIEW LETTERS LA English DT Article ID D-WAVE SUPERCONDUCTORS; LU SINGLE-CRYSTALS; DENSITY-OF-STATES; CUPRATE SUPERCONDUCTORS; YNI2B2C; VORTEX; TRANSPORT; PHASES; HEAT; UPT3 AB The thermal conductivity of borocarbide superconductor LuNi2B2C was measured down to 70 mK (T-c/200) in a magnetic field perpendicular to the heat current from H = 0 to above H-c2 = 7 T. As soon as vortices enter the sample, the conduction at T --> 0 grows rapidly, showing unambiguously that delocalized quasiparticles are present at the lowest energies. The field dependence is very similar to that Of UPt3, a heavy-fermion superconductor with a line of nodes in the gap, and very different from the exponential dependence characteristic of s-wave superconductors. This is strong evidence for a highly anisotropic gap function in LuNi2B2C, possibly with nodes. C1 Univ Toronto, Dept Phys, Canadian Inst Adv Res, Toronto, ON M5S 1A7, Canada. Iowa State Univ, Dept Phys & Astron, Ames Lab, Ames, IA 50011 USA. RP Boaknin, E (reprint author), Univ Toronto, Dept Phys, Canadian Inst Adv Res, 60 St George St, Toronto, ON M5S 1A7, Canada. RI Lupien, Christian/C-2148-2008; Canfield, Paul/H-2698-2014 OI Lupien, Christian/0000-0003-1767-8603; NR 31 TC 82 Z9 82 U1 1 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 3 PY 2001 VL 87 IS 23 AR 237001 DI 10.1103/PhysRevLett.87.237001 PG 4 WC Physics, Multidisciplinary SC Physics GA 498ZZ UT WOS:000172545400037 PM 11736470 ER PT J AU Chanowitz, MS AF Chanowitz, MS TI Z ->(b)over-bar-b decay asymmetry: Lose-lose for the standard model SO PHYSICAL REVIEW LETTERS LA English DT Article AB Combining precision measurements and the Higgs boson search limit, the electroweak data have evolved to a point where new physics is favored whether the 3.2 sigma A(FB)(b) anomaly is genuine or not. Such new physics could greatly alter the inferred value of the Higgs boson mass. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Theoret Phys Grp, Berkeley, CA 94720 USA. RP Chanowitz, MS (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Theoret Phys Grp, Berkeley, CA 94720 USA. NR 11 TC 66 Z9 66 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 3 PY 2001 VL 87 IS 23 AR 231802 DI 10.1103/PhysRevLett.87.231802 PG 4 WC Physics, Multidisciplinary SC Physics GA 498ZZ UT WOS:000172545400012 PM 11736445 ER PT J AU Damascelli, A Shen, KM Lu, DH Shen, ZX AF Damascelli, A Shen, KM Lu, DH Shen, ZX TI Comment on "Fermi surface, surface states, and surface reconstruction in Sr2RuO4" - Reply SO PHYSICAL REVIEW LETTERS LA English DT Editorial Material ID SUPERCONDUCTOR SR2RUO4 C1 Stanford Univ, Dept Phys Appl Phys, Stanford, CA 94305 USA. Stanford Univ, Stanford Synchrotron Radiat Lab, Stanford, CA 94305 USA. RP Damascelli, A (reprint author), Stanford Univ, Dept Phys Appl Phys, Stanford, CA 94305 USA. RI Shen, Kyle/B-3693-2008; damascelli, andrea/P-6329-2014 OI damascelli, andrea/0000-0001-9895-2226 NR 10 TC 10 Z9 10 U1 0 U2 6 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 3 PY 2001 VL 87 IS 23 AR 239702 DI 10.1103/PhysRevLett.87.239702 PG 1 WC Physics, Multidisciplinary SC Physics GA 498ZZ UT WOS:000172545400050 ER PT J AU Hebner, GA Riley, ME Johnson, DS Ho, P Buss, RJ AF Hebner, GA Riley, ME Johnson, DS Ho, P Buss, RJ TI Direct determination of particle-particle interactions in a 2D plasma dust crystal SO PHYSICAL REVIEW LETTERS LA English DT Article ID PHASE-TRANSITIONS; COULOMB CLUSTERS; YUKAWA SYSTEM; ROTATION; SHEATH; CHARGE AB Particle interactions were directly determined from the lateral compression of two-dimensional plasma dust crystals confined in a parabolic potential well. Measured particle separations combined with an equation of state for the crystal were used to derive values for the particle screening length and the charge on the particles. The shape of the parabolic potential well was confirmed by observing trajectories of single particles falling within the well. No evidence of a lateral particle-particle binding was observed. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Hebner, GA (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 26 TC 36 Z9 36 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 3 PY 2001 VL 87 IS 23 AR 235001 DI 10.1103/PhysRevLett.87.235001 PG 4 WC Physics, Multidisciplinary SC Physics GA 498ZZ UT WOS:000172545400021 PM 11736454 ER PT J AU Bulatov, VV AF Bulatov, VV TI Bottomless complexity of core structure and kink mechanisms of dislocation motion in silicon SO SCRIPTA MATERIALIA LA English DT Article DE elemental semiconductors; theory and modeling; lattice defects; dislocation mobility ID 90-DEGREES PARTIAL DISLOCATION; MOBILITY; SHUFFLE; GLIDE AB Dislocation core is imperfect and populated by a variety of zero-dimensional defect species-kinks, reconstruction defects, core vacancies, etc,, and their combinations. Structural origin of such a rich spectrum of core excitations and its possible contribution to dislocation behavior under stress is the topic of this contribution. (C) 2001 Acta Materialia Inc. Published by Elsevier Science Ltd. All rights reserved. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Bulatov, VV (reprint author), Lawrence Livermore Natl Lab, 7000 East Ave, Livermore, CA 94550 USA. NR 18 TC 10 Z9 10 U1 0 U2 3 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 3 PY 2001 VL 45 IS 11 BP 1247 EP 1252 DI 10.1016/S1359-6462(01)01157-5 PG 6 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 501JH UT WOS:000172681200003 ER PT J AU Yoshimi, K Yoo, MH Wereszczak, AA Borowicz, SM George, EP Zee, RH AF Yoshimi, K Yoo, MH Wereszczak, AA Borowicz, SM George, EP Zee, RH TI Yielding and flow behavior of Mo5Si3 single crystals SO SCRIPTA MATERIALIA LA English DT Article DE intermetallics; molybdenum silicide; slip; yield phenomena ID MECHANICAL-PROPERTIES; DISLOCATION DYNAMICS; OXIDATION BEHAVIOR; BORON; CREEP AB Deformation behavior Of Mo5Si3 was studied using single crystals under compression. It was found that yielding and flow behavior were strongly dependent on temperature, strain rate and crystal orientation. A stress exponent and an activation enthalpy of lower yield stresses were estimated to be approximate to 6 and 4.5 eV, respectively. (C) 2001 Acta Materialia Inc. Published by Elsevier Science Ltd. All rights reserved. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. Auburn Univ, Mat Engn Program, Auburn, AL 36849 USA. RP Yoshimi, K (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, POB 2008, Oak Ridge, TN 37831 USA. RI George, Easo/L-5434-2014; Wereszczak, Andrew/I-7310-2016 OI Wereszczak, Andrew/0000-0002-8344-092X NR 14 TC 29 Z9 30 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 3 PY 2001 VL 45 IS 11 BP 1321 EP 1326 DI 10.1016/S1359-6462(01)01170-8 PG 6 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 501JH UT WOS:000172681200014 ER PT J AU Feng, B Cao, DM Meng, WJ Xu, J Tittsworth, RC Rehn, LE Baldo, PM Doll, GL AF Feng, B Cao, DM Meng, WJ Xu, J Tittsworth, RC Rehn, LE Baldo, PM Doll, GL TI Characterization of microstructure and mechanical behavior of sputter deposited Ti-containing amorphous carbon coatings SO SURFACE & COATINGS TECHNOLOGY LA English DT Article DE nanocomposite; microstructure; mechanical behavior; amorphous carbon ID CONTAINING HYDROCARBON COATINGS; PLASMA-ASSISTED DEPOSITION; ROLLING-CONTACT FATIGUE; RAY-ABSORPTION-SPECTRA; STEEL AB We report on the characterization of microstructure and mechanical properties of sputter deposited Ti-containing amorphous carbon (Ti-aC) coatings as a function of Ti composition. Ti-aC coatings have been deposited by unbalanced magnetron sputter deposition, in an industrial-scale four-target coating deposition system. The composition and microstructure of the Ti-aC coatings have been characterized in detail by combining the techniques of Rutherford backscattering spectrometry (RBS) and hydrogen elastic recoil detection (ERD), transmission electron microscopy (TEM), X-ray absorption near edge structure (XANES) spectroscopy and extended X-ray absorption fine structure (EXAFS) spectroscopy. At Ti compositions < 4at.%, Ti atoms dissolve in an amorphous carbon (a-C) matrix. The dissolution limit of Ti atoms in an a-C matrix is determined to be between 4 and 8 at.%. At Ti compositions >8 at.%, XANES and EXAFS data indicate that the average Ti atomic bonding environment in Ti-aC coatings resembles that in cubic B1-TiC, consistent with TEM observation of precipitation of TiC nanocrystallites in the a-C matrix. Beyond the Ti dissolution limit, the Ti-aC coatings are nanocomposites with nanocrystalline TiC clusters embedded in an a-C matrix. A large scale, quasi one-dimensional composition modulation in the Ti-aC coatings was observed due to the particular coating deposition geometry. Elastic stiffness and hardness of the Ti-aC coatings were measured by instrumented nanoindentation and found to vary systematically as a function of Ti composition. Unlubricated friction coefficient of Ti-aC coatings against WC-Co balls was found to increase as the Ti composition increases. As Ti composition increases, the overall mechanical behavior of the Ti-aC coatings becomes more TiC-like. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Louisiana State Univ, Dept Mech Engn, Baton Rouge, LA 70803 USA. Louisiana State Univ, Ctr Adv Microstruct & Devices, Baton Rouge, LA 70803 USA. Argonne Natl Lab, Div Sci Mat, Argonne, IL 60439 USA. Timken Co, Timken Res, Canton, OH 44706 USA. RP Meng, WJ (reprint author), Louisiana State Univ, Dept Mech Engn, 2508 CEBA, Baton Rouge, LA 70803 USA. RI Cao, Dongmei/A-2481-2010 NR 19 TC 51 Z9 52 U1 0 U2 5 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0257-8972 J9 SURF COAT TECH JI Surf. Coat. Technol. PD DEC 3 PY 2001 VL 148 IS 2-3 BP 153 EP 162 DI 10.1016/S0257-8972(01)01380-9 PG 10 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 504UZ UT WOS:000172875400008 ER PT J AU Amestoy, PR Duff, IS L'Excellent, JY Li, XS AF Amestoy, PR Duff, IS L'Excellent, JY Li, XS TI Analysis and comparison of two general sparse solvers for distributed memory computers SO ACM TRANSACTIONS ON MATHEMATICAL SOFTWARE LA English DT Article DE algorithms; performance; sparse direct solvers; parallelism; distributed-memory computers; multifrontal and supernodal factorizations ID PARALLEL ALGORITHMS; LU FACTORIZATION; LINEAR-SYSTEMS; MULTIPROCESSORS; ELIMINATION; MATRICES AB This paper provides a comprehensive study and comparison of two state-of-the-art direct solvers for large sparse sets of linear equations on large-scale distributed. memory computers. One is a multifrontal solver called MUMPS, the other is a supernodal solver called SuperLU. We describe the main algorithmic features of the two solvers and compare their performance characteristics with respect to uniprocessor speed, interprocessor communication, and memory requirements. For both solvers, preorderings for numerical stability and sparsity play an important role in achieving high parallel efficiency. We analyse the results with various ordering algorithms. Our performance analysis is based on data obtained from runs on a 512-processor Cray T3E using a set of matrices from real applications. We also use regular 3D grid problems to study the scalability of the two solvers. C1 ENSEEIHT IRIT, F-31071 Toulouse, France. CERFACS, F-31527 Toulouse 1, France. Ecole Normale Super Lyon, LIP, F-69364 Lyon 07, France. Univ Calif Berkeley, Lawrence Berkeley Lab, NERSC, Berkeley, CA 94720 USA. Rutherford Appleton Lab, F-31527 Toulouse 1, France. RP Amestoy, PR (reprint author), ENSEEIHT IRIT, 2 Rue Camichel, F-31071 Toulouse, France. NR 34 TC 25 Z9 25 U1 1 U2 3 PU ASSOC COMPUTING MACHINERY PI NEW YORK PA 1515 BROADWAY, NEW YORK, NY 10036 USA SN 0098-3500 J9 ACM T MATH SOFTWARE JI ACM Trans. Math. Softw. PD DEC PY 2001 VL 27 IS 4 BP 388 EP 421 DI 10.1145/504210.504212 PG 34 WC Computer Science, Software Engineering; Mathematics, Applied SC Computer Science; Mathematics GA 526WZ UT WOS:000174154000002 ER PT J AU Bryan, JC Levitskaia, TG AF Bryan, JC Levitskaia, TG TI Tetrabenzo-24-crown-8 tris(1,2-dichloroethane) solvate SO ACTA CRYSTALLOGRAPHICA SECTION C-CRYSTAL STRUCTURE COMMUNICATIONS LA English DT Article ID CESIUM AB The title compound, C32H32O8. 3C(2)H(4)Cl(2), illustrates how tetrabenzo-24-crown-8 may be solvated by a common solvent-extraction diluent, 1,2-dichloroethane (DCE). Two molecules of DCE occupy the crown cavity, forming weak hydrogen bonds to the ether O atoms and the crown arene rings, while the crown adopts its most commonly observed binding conformation. The asymmetric unit is composed of two molecules of tetrabenzo-24-crown-8 and six molecules of DCE. C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Bryan, JC (reprint author), Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. NR 13 TC 1 Z9 1 U1 0 U2 1 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 PY 2001 VL 57 BP 1457 EP 1459 DI 10.1107/S0108270101014627 PN 12 PG 3 WC Chemistry, Multidisciplinary; Crystallography SC Chemistry; Crystallography GA 499AT UT WOS:000172548200034 PM 11740116 ER PT J AU Terwilliger, TC AF Terwilliger, TC TI Maximum-likelihood density modification using pattern recognition of structural motifs SO ACTA CRYSTALLOGRAPHICA SECTION D-BIOLOGICAL CRYSTALLOGRAPHY LA English DT Article ID X-RAY CRYSTALLOGRAPHY; PHASE REFINEMENT; MACROMOLECULAR CRYSTALLOGRAPHY; PROTEIN CRYSTALLOGRAPHY; COMBINING CONSTRAINTS; HOLOGRAPHIC METHODS; IMPROVEMENT; EXTENSION; ENTROPY; MAPS C1 Los Alamos Natl Lab, Biosci Div, Los Alamos, NM 87545 USA. RP Terwilliger, TC (reprint author), Los Alamos Natl Lab, Biosci Div, Mail Stop M888, Los Alamos, NM 87545 USA. RI Terwilliger, Thomas/K-4109-2012 OI Terwilliger, Thomas/0000-0001-6384-0320 NR 40 TC 149 Z9 151 U1 0 U2 3 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0907-4449 J9 ACTA CRYSTALLOGR D JI Acta Crystallogr. Sect. D-Biol. Crystallogr. PD DEC PY 2001 VL 57 BP 1755 EP 1762 DI 10.1107/S0907444901013737 PN 12 PG 8 WC Biochemical Research Methods; Biochemistry & Molecular Biology; Biophysics; Crystallography SC Biochemistry & Molecular Biology; Biophysics; Crystallography GA 495CE UT WOS:000172322000001 PM 11717487 ER PT J AU Terwilliger, TC AF Terwilliger, TC TI Map-likelihood phasing SO ACTA CRYSTALLOGRAPHICA SECTION D-BIOLOGICAL CRYSTALLOGRAPHY LA English DT Article ID NON-CRYSTALLOGRAPHIC SYMMETRY; X-RAY CRYSTALLOGRAPHY; DNA-BINDING-PROTEIN; DENSITY-MODIFICATION; RECIPROCAL-SPACE; MOLECULAR REPLACEMENT; COMBINING CONSTRAINTS; HOLOGRAPHIC METHODS; CRYSTAL-STRUCTURES; MAXIMUM-ENTROPY AB The recently developed technique of maximum-likelihood density modification [Terwilliger (2000), Acta Cryst. D56, 965-972] allows a calculation of phase probabilities based on the likelihood of the electron-density map to be carried out separately from the calculation of any prior phase probabilities. Here, it is shown that phase-probability distributions calculated from the map-likelihood function alone can be highly accurate and that they show minimal bias towards the phases used to initiate the calculation. Map-likelihood phase probabilities depend upon expected characteristics of the electron-density map, such as a defined solvent region and expected electron-density distributions within the solvent region and the region occupied by a macromolecule. In the simplest case, map-likelihood phase-probability distributions are largely based on the flatness of the solvent region. Though map-likelihood phases can be calculated without prior phase information, they are greatly enhanced by high-quality starting phases. This leads to the technique of prime-and-switch phasing for removing model bias. In prime-and-switch phasing, biased phases such as those from a model are used to prime or initiate map-likelihood phasing, then final phases are obtained from map-likelihood phasing alone. Map-likelihood phasing can be applied in cases with solvent content as low as 30%. Potential applications of map-likelihood phasing include unbiased phase calculation from molecular-replacement models, iterative model building, unbiased electron-density maps for cases where 2F(o)-F-c or sigma (A)-weighted maps would currently be used, structure validation and ab initio phase determination from solvent masks, non-crystallographic symmetry or other knowledge about expected electron density. C1 Los Alamos Natl Lab, Biosci Div, Los Alamos, NM 87545 USA. RP Terwilliger, TC (reprint author), Los Alamos Natl Lab, Biosci Div, Mail Stop M888, Los Alamos, NM 87545 USA. RI Terwilliger, Thomas/K-4109-2012 OI Terwilliger, Thomas/0000-0001-6384-0320 NR 50 TC 74 Z9 74 U1 0 U2 4 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0907-4449 J9 ACTA CRYSTALLOGR D JI Acta Crystallogr. Sect. D-Biol. Crystallogr. PD DEC PY 2001 VL 57 BP 1763 EP 1775 DI 10.1107/S0907444901013749 PN 12 PG 13 WC Biochemical Research Methods; Biochemistry & Molecular Biology; Biophysics; Crystallography SC Biochemistry & Molecular Biology; Biophysics; Crystallography GA 495CE UT WOS:000172322000002 PM 11717488 ER PT J AU Von Dreele, RB AF Von Dreele, RB TI Binding of N-acetylglucosamine to chicken egg lysozyme: a powder diffraction study SO ACTA CRYSTALLOGRAPHICA SECTION D-BIOLOGICAL CRYSTALLOGRAPHY LA English DT Article ID PROTEIN CRYSTAL-STRUCTURE; WHITE LYSOZYME; HEN; RESOLUTION; REFINEMENT; COMPLEX; BOOK; LIFE AB The binding of N-acetylglucosamine (NAG) to chicken egg lysozyme (E.C. 3.2.1.17) was investigated by high-resolution X-ray powder diffraction at room temperature. NAG was found to bind to lysozyme in a rapid precipitation preparation with 0.05 M NaCl buffer pH 6.0, but not 0.05 M NaCl buffer pH 5.0. Binding was indicated by significant and readily apparent changes in the diffraction pattern from that of the apo protein precipitated from the same solvent. The location of NAG bound to lysozyme was easily found from a difference Fourier map generated from structure factors extracted during a preliminary combined Rietveld and stereochemical restraint refinement. Full protein and protein-NAG structures were refined with these techniques (R(wp) = 2.22-2.49%, R(p) = 1.79-1.95%, R(F)(2) = 4.95-6.35%) and revealed a binding mode for NAG which differed from that found in an earlier single-crystal study and probably represents a precursor trapped by rapid precipitation. C1 Los Alamos Natl Lab, Manuel Lujan Jr Neutron Scattering Ctr, Los Alamos, NM 87545 USA. RP Von Dreele, RB (reprint author), Los Alamos Natl Lab, Manuel Lujan Jr Neutron Scattering Ctr, MS H805, Los Alamos, NM 87545 USA. EM vondreele@lanl.gov NR 26 TC 37 Z9 37 U1 1 U2 10 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 0907-4449 J9 ACTA CRYSTALLOGR D JI Acta Crystallogr. Sect. D-Biol. Crystallogr. PD DEC PY 2001 VL 57 BP 1836 EP 1842 DI 10.1107/S0907444901015748 PN 12 PG 7 WC Biochemical Research Methods; Biochemistry & Molecular Biology; Biophysics; Crystallography SC Biochemistry & Molecular Biology; Biophysics; Crystallography GA 495CE UT WOS:000172322000010 PM 11717496 ER PT J AU Brodsky, SJ AF Brodsky, SJ TI QCD phenomenology and light-front wavefunctions SO ACTA PHYSICA POLONICA B LA English DT Article; Proceedings Paper CT 41st Cracow School of Theoretical Physics CY JUN 02-11, 2001 CL ZAKOPANE, POLAND ID VIRTUAL COMPTON-SCATTERING; LARGE-MOMENTUM-TRANSFER; TRANSITION FORM-FACTOR; PIONS DISTRIBUTION AMPLITUDE; ORBITAL ANGULAR-MOMENTUM; YANG-MILLS THEORY; PERTURBATIVE QCD; QUANTUM CHROMODYNAMICS; EXCLUSIVE PROCESSES; TRANSVERSE LATTICE AB A natural calculus for describing the bound-state structure of relativistic composite systems in quantum field theory is the light-front Fock expansion which encodes the properties of a hadrons in terms of a set of frame-in dependent n-particle wavefunctions. Light-front quantization in the doubly-transverse light-cone gauge has a number of remarkable advantages, including explicit unitarity, a physical Fock expansion, the absence of ghost degrees of freedom, and the decoupling properties needed to prove factorization theorems in high momentum transfer inclusive and exclusive reactions. A number of applications are discussed in these lectures, including semileptonic B decays, two-photon exclusive reactions, diffractive dissociation into jets, and deeply virtual Compton scattering. The relation of the intrinsic sea to the light-front wavefunctions is discussed. Light-front quantization can also be used in the Hamiltonian form to construct an event generator for high energy physics reactions at the amplitude level. The light-cone partition function, summed over exponentially-weighted light-cone energies, has simple boost properties which may be useful for studies in heavy ion collisions. I also review recent work which shows that the structure functions measured in deep inelastic lepton scattering are affected by final-state rescattering, thus modifying their connection to light-front probability distributions. In particular, the shadowing of nuclear structure functions is due to destructive interference effects from leading-twist diffraction of the virtual photon, physics not included in the nuclear light-cone wavefunctions. C1 Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Brodsky, SJ (reprint author), Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. EM sjbth@slac.stanford.edu NR 187 TC 16 Z9 16 U1 0 U2 1 PU WYDAWNICTWO UNIWERSYTETU JAGIELLONSKIEGO PI KRAKOW PA UL GRODZKA 26, KRAKOW, 31044, POLAND SN 0587-4254 J9 ACTA PHYS POL B JI Acta Phys. Pol. B PD DEC PY 2001 VL 32 IS 12 BP 4013 EP 4067 PG 55 WC Physics, Multidisciplinary SC Physics GA 515UL UT WOS:000173515000005 ER PT J AU Kunicka, J Malin, M Zelmanovic, D Katzenberg, M Canfield, W Shapiro, P Mohandas, N AF Kunicka, J Malin, M Zelmanovic, D Katzenberg, M Canfield, W Shapiro, P Mohandas, N TI Automated quantitation of hemoglobin-based blood substitutes in whole blood samples SO AMERICAN JOURNAL OF CLINICAL PATHOLOGY LA English DT Article DE blood substitutes; hemoglobin measurement methods; RBC indices; light scatter; flow cytometry ID TRANSFUSION; SURGERY; VOLUME AB It is necessary to develop methods for accurate monitoring of cell-free hemoglobin in circulation. Routine monitoring of circulating cell-free hemoglobin will be useful for evaluating the efficacy of blood substitute administration and for determining the clearance rates of the blood substitute from circulation. In addition, discriminating between cell-fi-ee hemoglobin and cell-associated hemoglobin will enable accurate determination of RBC indices, mean cell hemoglobin and mean corpuscular hemoglobin concentration, in individuals receiving hemoglobin-based blood substitutes. As colorimetric methods used by hematology analyzers to quantitate the hemoglobin value of a blood sample cannot distinguish between cell-associated and cell-free hemoglobin, it is currently not feasible to quantitate the levels of hemoglobin substitutes in circulation. The advent of a technology that measures volume and hemoglobin concentration of individual RBCs provides an alternative strategy for quantitating the cell-associated hemoglobin in a blood sample. We document that the combined use of cell-based and colorimetric hemoglobin measurements provides accurate discrimination between cell-associated and cell-free hemoglobin over a wide range of hemoglobin levels. This strategy should enable rapid and accurate monitoring of the levels of cell-free hemoglobin substitutes in the circulation of recipients of these blood substitutes. C1 Bayer, Lab Testing Segment, Tarrytown, NY USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, Berkeley, CA 94720 USA. RP Mohandas, N (reprint author), New York Blood Ctr, 310 E 67th St, New York, NY 10021 USA. NR 10 TC 10 Z9 10 U1 0 U2 0 PU AMER SOC CLIN PATHOLOGISTS PI CHICAGO PA 2100 W HARRISON ST, CHICAGO, IL 60612 USA SN 0002-9173 J9 AM J CLIN PATHOL JI Am. J. Clin. Pathol. PD DEC PY 2001 VL 116 IS 6 BP 913 EP 919 PG 7 WC Pathology SC Pathology GA 497JL UT WOS:000172451700018 PM 11764082 ER PT J AU Volkow, ND Chang, L Wang, GJ Fowler, JS Ding, YS Sedler, M Logan, J Franceschi, D Gatley, J Hitzemann, R Gifford, A Wong, C Pappas, N AF Volkow, ND Chang, L Wang, GJ Fowler, JS Ding, YS Sedler, M Logan, J Franceschi, D Gatley, J Hitzemann, R Gifford, A Wong, C Pappas, N TI Low level of brain dopamine D-2 receptors in methamphetamine abusers: Association with metabolism in the orbitofrontal cortex SO AMERICAN JOURNAL OF PSYCHIATRY LA English DT Article ID OBSESSIVE-COMPULSIVE DISORDER; POSITRON-EMISSION-TOMOGRAPHY; CONDITIONED PLACE PREFERENCE; DEPENDENT SUBJECTS; PREFRONTAL CORTEX; C-11 RACLOPRIDE; COCAINE ABUSERS; BLOOD-FLOW; DRUG; BINDING AB objective: The role of dopamine in the addictive process (loss of control and compulsive drug intake) is poorly understood. A consistent finding in drug-addicted subjects is a lower level of dopamine D-2 receptors. In cocaine abusers, low levels of D-2 receptors are associated with a lower level of metabolism in the orbitofrontal cortex. Because the orbitofrontal cortex is associated with compulsive behaviors, its disruption may contribute to compulsive drug intake in addicted subjects. This study explored whether a similar association occurs in methamphetamine abusers. Method: Fifteen methamphetamine abusers and 20 non-drug-abusing comparison subjects were studied with positron emission tomography (PET) and [C-11]raclopride to assess the availability of dopamine D-2 receptors and with [F-18]fluorodeoxyglucose to assess regional brain glucose metabolism, a marker of brain function. Results: Methamphetamine abusers had a significantly lower level of D-2 receptor availability than comparison subjects (a difference of 16% in the caudate and 10% in the putamen). D-2 receptor availability was associated with metabolic rate in the orbitofrontal cortex in abusers and in comparison subjects. Conclusions: Lower levels of dopamine D-2 receptor availability have been previously reported in cocaine abusers, alcoholics, and heroine abusers. This study extends this finding to methamphetamine abusers. The association between level of dopamine D-2 receptors and metabolism in the orbitofrontal cortex in methamphetamine abusers, which replicates previous findings in cocaine abusers, suggests that D-2 receptor-mediated dysregulation of the orbitofrontal cortex could underlie a common mechanism for loss of control and compulsive drug intake in drug-addicted subjects. C1 Brookhaven Natl Lab, Dept Med, Upton, NY 11973 USA. Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. SUNY Stony Brook, Dept Psychiat, Stony Brook, NY 11794 USA. RP Volkow, ND (reprint author), Brookhaven Natl Lab, Dept Med, BSA,POB 5000, Upton, NY 11973 USA. FU NCRR NIH HHS [RR-10710]; NIDA NIH HHS [DA-7092-01, DA-00280] NR 54 TC 469 Z9 489 U1 3 U2 20 PU AMER PSYCHIATRIC PRESS, INC PI WASHINGTON PA 1400 K ST, N W, STE 1101, WASHINGTON, DC 20005 USA SN 0002-953X J9 AM J PSYCHIAT JI Am. J. Psychiat. PD DEC PY 2001 VL 158 IS 12 BP 2015 EP 2021 DI 10.1176/appi.ajp.158.12.2015 PG 7 WC Psychiatry SC Psychiatry GA 497JQ UT WOS:000172452100012 PM 11729018 ER PT J AU Westneat, MW Betz, O Blob, R Fezzaa, K Cooper, J Lee, WK AF Westneat, MW Betz, O Blob, R Fezzaa, K Cooper, J Lee, WK TI A new view of insect biomechanics: Using synchrotron phase-enhanced x-ray imaging to study insect respiration, locomotion, and feeding. SO AMERICAN ZOOLOGIST LA English DT Meeting Abstract C1 Field Museum, Chicago, IL USA. Argonne Natl Lab, Argonne, IL 60439 USA. NR 0 TC 2 Z9 2 U1 1 U2 9 PU SOC INTEGRATIVE COMPARATIVE BIOLOGY PI MCLEAN PA 1313 DOLLEY MADISON BLVD, NO 402, MCLEAN, VA 22101 USA SN 0003-1569 J9 AM ZOOL JI Am. Zool. PD DEC PY 2001 VL 41 IS 6 BP 1623 EP 1624 PG 2 WC Zoology SC Zoology GA 529NX UT WOS:000174306500832 ER PT J AU Cavazzini, A Kaczmarski, K Szabelski, P Zhou, DM Liu, XD Guiochon, G AF Cavazzini, A Kaczmarski, K Szabelski, P Zhou, DM Liu, XD Guiochon, G TI Modeling of the separation of the enantiomers of 1-phenyl-1-propanol on cellulose tribenzoate SO ANALYTICAL CHEMISTRY LA English DT Article ID BOVINE SERUM-ALBUMIN; LIQUID-CHROMATOGRAPHIC SEPARATION; PROTEIN STATIONARY PHASES; ADSORPTION ENERGY-DISTRIBUTIONS; ANION-EXCHANGE CHROMATOGRAPHY; MASS-TRANSFER; OPTICAL RESOLUTION; AFFINITY-CHROMATOGRAPHY; FINITE-ELEMENTS; BAND PROFILES AB The competitive adsorption isotherms of rac-1-phenyl-1-propanol on cellulose tribenzoate were measured by competitive frontal analysis. The experimental data were fitted to four different isotherm models: Langmuir, Bi-langmuir, Langmuir-Freundlich, and Toth. The fittings of the experimental data to all four models were satisfactory. It was excellent in the case of the Langmuir-Freundlich and the Toth models. Overloaded elution profiles calculated with the Toth isotherm were in good agreement with the experimental profiles in all the different experimental conditions investigated. This work extends to the case of binary mixtures the equivalence between the general rate and the lumped pore diffusion models already demonstrated for pure compounds when the ratio between the Stanton and the Biot numbers exceeds 5. The adsorption energy distribution for the Toth isotherm was also calculated. 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. RI Cavazzini, Alberto/B-7051-2015 OI Cavazzini, Alberto/0000-0002-2510-0871 NR 59 TC 46 Z9 46 U1 1 U2 11 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 2001 VL 73 IS 23 BP 5704 EP 5715 DI 10.1021/ac010751z PG 12 WC Chemistry, Analytical SC Chemistry GA 498YM UT WOS:000172541200025 PM 11774911 ER PT J AU Rho, JY Mishra, SR Chung, K Bai, J Pharr, GM AF Rho, JY Mishra, SR Chung, K Bai, J Pharr, GM TI Relationship between ultrastructure and the nanoindentation properties of intramuscular herring bones SO ANNALS OF BIOMEDICAL ENGINEERING LA English DT Article; Proceedings Paper CT Conference on the Mechanical Properties of Cells and Tissues CY OCT 11-13, 1999 CL AUGUSTUSBURG, GERMANY DE nanoindentation; synchrotron x-ray radiation; bone crystal; ultrastructure; bone biomechanics; herring bone ID COLLAGEN FIBRILS; OSTEONAL BONE; LAMELLAR BONE; CRYSTALS; MODULUS; ANISOTROPY; HARDNESS; TISSUES AB The nanoindentation technique was used to characterize the indentation modulus of intramuscular herring bone (Clupea harengus) along its length, from early to fully mineralized regions. Both the indentation modulus and modulus anisotropy ratio, indentation modulus longitudinally/indentation modulus transversely, increased nonmonotonically with mineralization, from 1.1 in the early stages of mineralization to 2.1 in the fully mineralized region. The indentation modulus in the fully mineralized region decreased from 19.9 +/- 2.0GPa in the longitudinal direction to 11.4 +/- 1.5 GPa in the transverse directions. In the earliest stages of mineralization, the indentation modulus was 3.8 +/- 0.7GPa in the longitudinal direction and 3.5 +/- 0.3 GPa in the transverse direction. High-intensity synchrotron x rays were used to examine two parameters of crystal texture. the coherence length and the angular spread. Low angular spread was seen along the c axis of bone crystallite. However, the large angular spread observed along the (300) plane indicated an imperfection of crystallite periodicity in the direction perpendicular to the longitudinal axis in the bone. The relatively high coherence length was related to the low angular spread. In general, the indentation modulus increased with increasing crystallite size, but the indentation modulus decreased with increasing crystallite size along the (300) plane. (C) 2001 Biomedical Engineering Society. C1 Univ Memphis, Dept Biomed Engn, Memphis, TN 38152 USA. Univ Memphis, Dept Phys, Memphis, TN 38152 USA. Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN USA. Univ Tennessee, Dept Mat Sci, Knoxville, TN USA. RP Rho, JY (reprint author), Univ Memphis, Dept Biomed Engn, ET330, Memphis, TN 38152 USA. EM jrho@cc.memphis.edu RI Bai, Jianming/O-5005-2015 FU PHS HHS [NIH45297] NR 25 TC 31 Z9 31 U1 0 U2 8 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0090-6964 J9 ANN BIOMED ENG JI Ann. Biomed. Eng. PD DEC PY 2001 VL 29 IS 12 BP 1082 EP 1088 DI 10.1114/1.1424913 PG 7 WC Engineering, Biomedical SC Engineering GA 517LG UT WOS:000173611600009 PM 11853259 ER PT J AU Takai, K Moser, DP DeFlaun, M Onstott, TC Fredrickson, JK AF Takai, K Moser, DP DeFlaun, M Onstott, TC Fredrickson, JK TI Archaeal diversity in waters from deep South African gold mines SO APPLIED AND ENVIRONMENTAL MICROBIOLOGY LA English DT Article ID RIBOSOMAL-RNA SEQUENCES; MOLECULAR PHYLOGENETIC ANALYSIS; MARINE PLANKTONIC ARCHAEA; MICROBIAL DIVERSITY; KINGDOM CRENARCHAEOTA; SEDIMENTS; SOIL; SEA; ENVIRONMENTS; COMMUNITY AB A culture-independent molecular analysis of archaeal communities in waters collected from deep South African gold mines was performed by performing a PCR-mediated terminal restriction fragment length polymorphism (T-RFLP) analysis of rRNA genes (rDNA) in conjunction with a sequencing analysis of archaeal rDNA clone libraries. The water samples used represented various environments, including deep fissure water, mine service water, and water from an overlying dolomite aquifer. T-RFLP analysis revealed that the ribotype distribution of archaea varied with the source of water. The archaeal communities in the deep gold mine environments exhibited great phylogenetic diversity; the majority of the members were most closely related to uncultivated species. Some archaeal rDNA clones obtained from mine service water and dolomite aquifer water samples were most closely related to environmental rDNA clones from surface soil (soil clones) and marine environments (marine group I [MGI]). Other clones exhibited intermediate phylogenetic affiliation between soil clones and MGI in the Crenarchaeota. Fissure water samples, derived from active or dormant geothermal environments, yielded archaeal sequences that exhibited novel phylogeny, including a novel lineage of Euryarchaeota. These results suggest that deep South African gold mines harbor novel archaeal communities distinct from those observed in other environments. Based on the phylogenetic analysis of archaeal strains and rDNA clones, including the newly discovered archaeal rDNA clones, the evolutionary relationship and the phylogenetic organization of the domain Archaea are reevaluated. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. Japan Marine Sci & Technol Ctr, Frontier Res Program Deep Sea Environm, SUGAR Project, Yokosuka, Kanagawa 2370061, Japan. Envirogen Inc, Lawrenceville, NJ 08648 USA. Princeton Univ, Dept Geosci, Princeton, NJ 08544 USA. RP Fredrickson, JK (reprint author), MS P7-50,PO 999, Richland, WA 99352 USA. EM jim.fredrickson@pnl.gov NR 50 TC 239 Z9 256 U1 3 U2 39 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1752 N ST NW, WASHINGTON, DC 20036-2904 USA SN 0099-2240 J9 APPL ENVIRON MICROB JI Appl. Environ. Microbiol. PD DEC PY 2001 VL 67 IS 12 BP 5750 EP 5760 DI 10.1128/AEM.67.21.5750-5760.2001 PG 11 WC Biotechnology & Applied Microbiology; Microbiology SC Biotechnology & Applied Microbiology; Microbiology GA 497JM UT WOS:000172451800054 PM 11722932 ER PT J AU Wu, LY Thompson, DK Li, GS Hurt, RA Tiedje, JM Zhou, JZ AF Wu, LY Thompson, DK Li, GS Hurt, RA Tiedje, JM Zhou, JZ TI Development and evaluation of functional gene arrays for detection of selected genes in the environment SO APPLIED AND ENVIRONMENTAL MICROBIOLOGY LA English DT Article ID SACCHAROMYCES-CEREVISIAE; DENITRIFYING BACTERIA; MICROARRAY ANALYSIS; EXPRESSION ANALYSIS; ESCHERICHIA-COLI; DNA; GENOME; HYBRIDIZATION; SEDIMENTS; SCALE AB To determine the potential of DNA array technology for assessing functional gene diversity and distribution, a prototype microarray was constructed with genes involved in nitrogen cycling: nitrite reductase (nirS and nirK) genes, ammonia mono-oxygenase (amoA) genes, and methane mono-oxygenase (PmoA) genes from pure cultures and those cloned from marine sediments. In experiments using glass slide microarrays, genes possessing less than 80 to 85% sequence identity were differentiated under hybridization conditions of high stringency (65 degreesC). The detection limit for nirS genes was approximately I ng of pure genomic DNA and 25 ng of soil community DNA using our optimized protocol. A linear quantitative relationship (r(2) = 0.89 to 0.94) was observed between signal intensity and target DNA concentration over a range of I to 100 ng for genomic DNA (or genomic DNA equivalent) from both pure cultures and mixed communities. However, the quantitative capacity of microarrays for measuring the relative abundance of targeted genes in complex environmental samples is less clear due to divergent target sequences. Sequence divergence and probe length affected hybridization signal intensity within a certain range of sequence identity and size, respectively. This prototype functional gene array did reveal differences in the apparent distribution of nir and amoA and pmoA gene families in sediment and soil samples. Our results indicate that glass-based microarray hybridization has potential as a tool for revealing functional gene composition in natural microbial communities; however, more work is needed to improve sensitivity and quantitation and to understand the associated issue of specificity. C1 Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. Michigan State Univ, Ctr Microbial Ecol, E Lansing, MI 48824 USA. RP Zhou, JZ (reprint author), Oak Ridge Natl Lab, Div Environm Sci, POB 2008, Oak Ridge, TN 37831 USA. NR 37 TC 267 Z9 303 U1 5 U2 42 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1752 N ST NW, WASHINGTON, DC 20036-2904 USA SN 0099-2240 J9 APPL ENVIRON MICROB JI Appl. Environ. Microbiol. PD DEC PY 2001 VL 67 IS 12 BP 5780 EP 5790 DI 10.1128/AEM.67.12.5780-5790.2001 PG 11 WC Biotechnology & Applied Microbiology; Microbiology SC Biotechnology & Applied Microbiology; Microbiology GA 497JM UT WOS:000172451800057 PM 11722935 ER PT J AU Kane, SR Beller, HR Legler, TC Koester, CJ Pinkart, HC Halden, RU Happel, AM AF Kane, SR Beller, HR Legler, TC Koester, CJ Pinkart, HC Halden, RU Happel, AM TI Aerobic biodegradation of methyl tert-butyl ether by aquifer bacteria from leaking underground storage tank sites SO APPLIED AND ENVIRONMENTAL MICROBIOLOGY LA English DT Article ID ANAEROBIC BIODEGRADATION; CULTURE; MTBE; DEGRADATION; ALCOHOL; WATER AB The potential for aerobic methyl tert-butyl ether (MTBE) degradation was investigated with microcosms containing aquifer sediment and groundwater from four MTBE-contaminated sites characterized by oxygen-limited in situ conditions. MTBE depletion was observed for sediments from two sites (e.g., 4.5 mg/liter degraded in 15 days after a 4-day lag period), whereas no consumption of MTBE was observed for sediments from the other sites after 75 days. For sediments in which MTBE was consumed, 43 to 54% of added [U-C-14] MTBE was mineralized to (CO2)-C-14. Molecular phylogenetic analyses of these sediments indicated the enrichment of species closely related to a known MTBE-degrading bacterium, strain PM1. At only one site, the presence of water-soluble gasoline components significantly inhibited MTBE degradation and led to a more pronounced accumulation of the metabolite tert-butyl alcohol. Overall, these results suggest that the effects of oxygen and water-soluble gasoline components on in situ MTBE degradation will vary from site to site and that phylogenetic analysis may be a promising predictor of MTBE biodegradation potential. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Cent Washington Univ, Ellensburg, WA 98926 USA. RP Kane, SR (reprint author), Lawrence Livermore Natl Lab, L-542,7000 East Ave, Livermore, CA 94550 USA. RI Beller, Harry/H-6973-2014; Halden, Rolf/F-9562-2010 OI Halden, Rolf/0000-0001-5232-7361 NR 26 TC 63 Z9 66 U1 1 U2 7 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1752 N ST NW, WASHINGTON, DC 20036-2904 USA SN 0099-2240 J9 APPL ENVIRON MICROB JI Appl. Environ. Microbiol. PD DEC PY 2001 VL 67 IS 12 BP 5824 EP 5829 DI 10.1128/AEM.67.12.5824-5829.2001 PG 6 WC Biotechnology & Applied Microbiology; Microbiology SC Biotechnology & Applied Microbiology; Microbiology GA 497JM UT WOS:000172451800062 PM 11722940 ER PT J AU Sullivan, AB Drever, JI AF Sullivan, AB Drever, JI TI Geochemistry of suspended particles in a mine-affected mountain stream SO APPLIED GEOCHEMISTRY LA English DT Article ID METAL TRANSPORT; ELEMENT CONCENTRATIONS; DRAINAGE; RIVER; IRON; WATERS; TOXICITY; SEDIMENT; COLORADO; SULFATE AB The particles in a mine drainage and the creek into which it drains were examined using microbeam and filtration methods. The composition of the particles in the drainage and creek were distinctly different, though both carried a chemical signal from the mine. High concentrations of particles made up of Fe and S were seen in the drainage, especially during low flow. The molar Fe:S ratio of these suspended particles was 3.5:1. The influx of the mine drainage into the creek increased the relative number of aggregates and particles with associated Fe. However, few discrete Fe-S particles were seen in the creek, where solid-phase Fe and S were consistently associated with aluminosilicate minerals. Instream precipitation is predicted and appears to be an important additional source of Fe and Al oxyhydroxides to the particles. Some of the Fe and Al associated with particles in the creek was acid-soluble, but most of the acid-soluble Zn, Mn, Cu, Ca, Mg and Si were transported in the <0.45 mum fraction at a site downstream of the mine drainage. One third of the suspended particles had associated P. These suspended particles take part in the complex geochemistry of this system, and represent an important pool as a potential sink and source of metals and other elements. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Univ Wyoming, Dept Geol & Geophys, Laramie, WY 82071 USA. RP Sullivan, AB (reprint author), Oak Ridge Natl Lab, Div Environm Sci, POB 2008, Oak Ridge, TN 37831 USA. NR 42 TC 16 Z9 16 U1 0 U2 4 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0883-2927 J9 APPL GEOCHEM JI Appl. Geochem. PD DEC PY 2001 VL 16 IS 15 BP 1663 EP 1676 DI 10.1016/S0883-2927(01)00064-6 PG 14 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 477EQ UT WOS:000171270500001 ER PT J AU Manes, PC Weaver, PF AF Manes, PC Weaver, PF TI Evidence for three distinct hydrogenase activities in Rhodospirillum rubrum SO APPLIED MICROBIOLOGY AND BIOTECHNOLOGY LA English DT Article ID CARBON-MONOXIDE DEHYDROGENASE; MEMBRANE-BOUND HYDROGENASE; RHODOPSEUDOMONAS-CAPSULATA; ACETYLENE; CO; FERMENTATION; INHIBITION; BACTERIA; OXYGEN AB Inducer, inhibitor, and mutant studies on three hydrogenase activities of Rhodospirillum rubrum indicate that they are mediated by three distinct hydrogenase enzymes. Uptake hydrogenase mediates H-2 uptake to an unknown physiological acceptor or methylene blue and is maximally synthesized during autotrophic growth in light. Formate-linked hydrogenase is synthesized primarily during growth in darkness or when light becomes limiting, and links formate oxidation to H-2 production. Carbon-monoxide-linked hydrogenase is induced whenever CO is present and couples CO oxidation to H-2 evolution. The enzymes can be expressed singly or conjointly depending on growth conditions, and the inhibitor or inducer added. All three hydrogenases can use methyl viologen as the mediator for both the H-2 evolution and H-2 uptake reactions while displaying distinct pH optima, reversibility, and sensitivity to C2H2, gas. Yet, we present evidence that the CO-linked hydrogenase, unlike the uptake hydrogenase, does not link to methylene blue as the electron acceptor. These differences allow conditions to be established to quantitatively assay each hydrogenase independently of the others both in vivo and in vitro. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Manes, PC (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 34 TC 25 Z9 29 U1 1 U2 2 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0175-7598 J9 APPL MICROBIOL BIOT JI Appl. Microbiol. Biotechnol. PD DEC PY 2001 VL 57 IS 5-6 BP 751 EP 756 PG 6 WC Biotechnology & Applied Microbiology SC Biotechnology & Applied Microbiology GA 506FT UT WOS:000172959700025 PM 11778889 ER PT J AU Scrymgeour, DA Barad, Y Gopalan, V Gahagan, KT Jia, QX Mitchell, TE Robinson, JM AF Scrymgeour, DA Barad, Y Gopalan, V Gahagan, KT Jia, QX Mitchell, TE Robinson, JM TI Large-angle electro-optic laser scanner on LiTaO3 fabricated by in situ monitoring of ferroelectric-domain micropatterning SO APPLIED OPTICS LA English DT Article ID IMAGING MICROSCOPY; BEAM SCANNERS; CRYSTALS; PROPAGATION; DEFLECTION; LINBO3 AB We report on a hom-shaped electro-optic scanner based on a ferroelectric LiTaO3 wafer that is capable of scanning 632.8-nm light by an unprecedented 14.88 degrees angle for extraordinary polarized light and by 4.05 degrees for ordinary polarized light. The device concept is based on micropatterning ferroelectric domains in the shape of a series of optimized prisms whose refractive index is electric field tunable through the electro-optic effect. We demonstrate what we believe is a novel technique of using electro-optic imaging microscopy for in situ monitoring of the process of domain micropatterning during device fabrication, thus eliminating imperfect process control based on ex situ monitoring of transient currents. (C) 2001 Optical Society of America. C1 Penn State Univ, Mat Res Lab, University Pk, PA 16802 USA. Penn State Univ, Dept Mat Sci & Engn, University Pk, PA 16802 USA. Los Alamos Natl Lab, Div Chem Sci & Technol, Los Alamos, NM 87545 USA. RP Scrymgeour, DA (reprint author), Penn State Univ, Mat Res Lab, University Pk, PA 16802 USA. EM vgopalan@psu.edu RI Scrymgeour, David/C-1981-2008; Jia, Q. X./C-5194-2008 NR 18 TC 40 Z9 49 U1 1 U2 10 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1559-128X EI 2155-3165 J9 APPL OPTICS JI Appl. Optics PD DEC 1 PY 2001 VL 40 IS 34 BP 6236 EP 6241 DI 10.1364/AO.40.006236 PG 6 WC Optics SC Optics GA 501YE UT WOS:000172713000014 PM 18364927 ER PT J AU Drager, G Kirchner, T Bocharov, S Kao, CC AF Drager, G Kirchner, T Bocharov, S Kao, CC TI Spin-resolved NEXAFS from resonant X-ray scattering (RXS): Application to MnO SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article AB Resonantly excited metal K core line spectra of NiO, MnO, CuO and other compounds have been investigated at the beamlines X21 (NSLS/BNL), BW1 and W1.1 (HASYLAB/DESY). A novel technique for quantitative resolution of NEXAFS spectra into spin-up and spin-down components has been developed. Since the method employs spin conservation and local spin references, it needs no circularly polarized radiation and no sample magnetization for taking both the RXS and NEXAFS spectra. Hence antiferromagnetic and paramagnetic materials can be investigated as well. By utilizing linear dichroism with angular-dependent measurements on single-crystal samples, additional resolution of NEXAFS spectra is possible with respect to the orbital symmetry. Application of the method to paramagnetic MnO, for the first time, provides new and unambiguous experimental results confirming modern (LSDA+U) calculations. C1 Univ Halle Wittenberg, Fachbereich Phys, D-06108 Halle Saale, Germany. Brookhaven Natl Lab, NSLS, Upton, NY 11973 USA. RP Drager, G (reprint author), Univ Halle Wittenberg, Fachbereich Phys, D-06108 Halle Saale, Germany. NR 6 TC 5 Z9 5 U1 0 U2 9 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0947-8396 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD DEC PY 2001 VL 73 IS 6 BP 687 EP 691 DI 10.1007/s003390100961 PG 5 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 496QR UT WOS:000172407900006 ER PT J AU Eimuller, T Fischer, P Kohler, M Scholz, M Guttmann, P Denbeaux, G Gluck, S Bayreuther, G Schmahl, G Attwood, D Schutz, G AF Eimuller, T Fischer, P Kohler, M Scholz, M Guttmann, P Denbeaux, G Gluck, S Bayreuther, G Schmahl, G Attwood, D Schutz, G TI Transmission X-ray microscopy using X-ray magnetic circular dichroism SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article ID DOMAINS AB X-ray magnetic circular dichroism (X-MCD) was used as a large, element-specific and quantitative magnetic contrast mechanism in the soft X-ray microscopes at BESSY I (Berlin) and the ALS (Berkeley). The present state and potential of magnetic transmission X-ray microscopy (MTXM) is outlined. The possibility to record images in varying magnetic fields and the high spatial resolution down to 25 nm were used to image out-of-plane magnetized (4 Angstrom Fe / 4 Angstrom Gd) x 75 systems. Magnetic domains could be studied in arrays of circular and square dots with lateral dimensions down to 180 nm. Hysteresis loops of individual dots were deduced using the direct proportionality of the X-MCD contrast to the sample magnetization. Images of a 3 nm Cr / 50 nm Fe / 6 nm Cr film demonstrate for the first time that MTXM is also able to observe in-plane magnetized domains. In the future the possible applications of MTXM will be extended with regard to the strength of the external field, the available energy range and the sample conditions by building a dedicated transmission X-ray microscope for magnetic imaging at BESSY II. C1 Univ Wurzburg, D-97074 Wurzburg, Germany. Univ Regensburg, Inst Expt & Angew Phys, D-93040 Regensburg, Germany. Univ Gottingen, Inst Rontgenphys, D-37073 Gottingen, Germany. Lawrence Berkeley Natl Lab, Ctr Xray Opt, Berkeley, CA 94720 USA. RP Eimuller, T (reprint author), Univ Wurzburg, Hubland, D-97074 Wurzburg, Germany. RI Fischer, Peter/A-3020-2010; Guttmann, Peter/H-9869-2015 OI Fischer, Peter/0000-0002-9824-9343; Guttmann, Peter/0000-0002-0534-238X NR 16 TC 10 Z9 10 U1 1 U2 9 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0947-8396 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD DEC PY 2001 VL 73 IS 6 BP 697 EP 701 DI 10.1007/s003390100963 PG 5 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 496QR UT WOS:000172407900008 ER PT J AU Hill, JP Nelson, CS von Zimmermann, M Kim, YJ Gibbs, D Casa, D Keimer, B Murakami, Y Venkataraman, C Gog, T Tomioka, Y Tokura, Y Kiryukhin, V Koo, TY Cheong, SW AF Hill, JP Nelson, CS von Zimmermann, M Kim, YJ Gibbs, D Casa, D Keimer, B Murakami, Y Venkataraman, C Gog, T Tomioka, Y Tokura, Y Kiryukhin, V Koo, TY Cheong, SW TI Orbital correlations in doped manganites SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article ID X-RAY-SCATTERING; CHARGE-ORDERED STATE; PR1-XCAXMNO3; LA0.5SR1.5MNO4; LA1-XSRXMNO3; DIFFRACTION; TRANSITION; LAMNO3; DYB2C2 AB We review our recent X-ray scattering studies of charge and orbital order in doped manganites, with specific emphasis on the role of orbital correlations in Pr-1_xCaxMnO3. For x = 0.25, we find an orbital structure indistinguishable from the undoped structure and long-range orbital order at low temperatures. For dopings 0.3 less than or equal to x less than or equal to 0.5, we find scattering consistent with a charge and orbitally ordered CE-type structure. While in each case the charge order peaks are resolution limited, the orbital order exhibits only short-range correlations. We report the doping dependence of the correlation length and discuss the connection between the orbital correlations and the finite magnetic correlation length observed on the Mn3+ sublattice with neutron-scattering techniques. The physical origin of these domains, which appear to be isotropic, remains unclear. We find that weak orbital correlations persist well above the phase transition, with a correlation length of 1-2 lattice constants at high temperatures. Significantly, we observe similar correlations at high temperatures in La0.7Ca0.3MnO3, which does not have an orbitally ordered ground state, and we conclude that such correlations are robust to variations in the relative strength of the electron-phonon coupling. C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Princeton Univ, Dept Phys, Princeton, NJ 08544 USA. Max Planck Inst Festkorperforsch, D-70569 Stuttgart, Germany. High Energy Accelerator Res Org, Photon Factory, Inst Mat Struct Sci, Tsukuba, Ibaraki 3050801, Japan. Argonne Natl Lab, Adv Photon Source, CMC, CAT, Argonne, IL 60439 USA. Joint Res Ctr Atom Technol, Tsukuba, Ibaraki 3050033, Japan. Univ Tokyo, Dept Appl Phys, Tokyo 1130033, Japan. Rutgers State Univ, Dept Phys & Astron, Piscataway, NJ 08854 USA. Bell Labs, Lucent Technol, Murray Hill, NJ 07974 USA. RP Hill, JP (reprint author), Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RI Kim, Young-June /G-7196-2011; Tokura, Yoshinori/C-7352-2009; Casa, Diego/F-9060-2016 OI Kim, Young-June /0000-0002-1172-8895; NR 52 TC 25 Z9 25 U1 1 U2 9 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0947-8396 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD DEC PY 2001 VL 73 IS 6 BP 723 EP 730 DI 10.1007/s003390100968 PG 8 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 496QR UT WOS:000172407900013 ER PT J AU Zhidkov, AG Zhigilei, LV Sasaki, A Tajima, T AF Zhidkov, AG Zhigilei, LV Sasaki, A Tajima, T TI Short-laser-pulse-driven emission of energetic ions into a solid target from a surface layer spalled by a laser prepulse SO APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING LA English DT Article ID ORGANIC-SOLIDS; FEMTOSECOND LASER; DENSITY TARGETS; ABLATION; PLASMA; DESORPTION; NUCLEI; FOILS; ACCELERATION; TEMPERATURE AB An efficient emission of picosecond bunches of energetic protons and carbon ions from a thin layer spalled from a organic solid by a laser prepulse is demonstrated numerically. We combine the molecular dynamics technique and multi-component collisional particle-in-cell method with plasma ionization to simulate the laser spallation and ejection of a thin (similar to 20-30 nm) solid layer from an organic target and its further interaction with an intense femtosecond laser pulse. In spite of its small thickness, a layer produced by laser spallation efficiently absorbs ultrashort laser pulses with the generation of hot electrons that convert their energy to ion energy. The efficiency of the conversion of the laser energy to ions can be as high as 20%, and 10% to MeV ions. A transient electrostatic field created between the layer and surface of the target is up to 10 GV/cm. C1 Univ Virginia, Dept Mat Sci & Engn, Charlottesville, VA 22903 USA. JAERI, Adv Photon Res Ctr, Neyagawa, Osaka 5720019, Japan. Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Inst Gen Phys, Moscow 117945, Russia. RP Zhigilei, LV (reprint author), Univ Virginia, Dept Mat Sci & Engn, Charlottesville, VA 22903 USA. RI Zhigilei, Leonid/E-2167-2012; Sasaki, Akira/J-8158-2016 NR 36 TC 15 Z9 16 U1 0 U2 4 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0947-8396 J9 APPL PHYS A-MATER JI Appl. Phys. A-Mater. Sci. Process. PD DEC PY 2001 VL 73 IS 6 BP 741 EP 747 DI 10.1007/s003390100887 PG 7 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 496QR UT WOS:000172407900016 ER PT J AU Fan, XH Narayanan, VK Lupton, RH Strauss, MA Knapp, GR Becker, RH White, RL Pentericci, L Leggett, SK Haiman, Z Gunn, JE Ivezic, Z Schneider, DP Anderson, SF Brinkmann, J Bahcall, NA Connolly, AJ Csabai, I Doi, M Fukugita, M Geballe, T Grebel, EK Harbeck, D Hennessy, G Lamb, DQ Miknaitis, G Munn, JA Nichol, R Okamura, S Pier, JR Prada, F Richards, GT Szalay, A York, DG AF Fan, XH Narayanan, VK Lupton, RH Strauss, MA Knapp, GR Becker, RH White, RL Pentericci, L Leggett, SK Haiman, Z Gunn, JE Ivezic, Z Schneider, DP Anderson, SF Brinkmann, J Bahcall, NA Connolly, AJ Csabai, I Doi, M Fukugita, M Geballe, T Grebel, EK Harbeck, D Hennessy, G Lamb, DQ Miknaitis, G Munn, JA Nichol, R Okamura, S Pier, JR Prada, F Richards, GT Szalay, A York, DG TI A survey of z > 5.8 quasars in the Sloan Digital Sky Survey. I. Discovery of three new quasars and the spatial density of luminous quasars at z similar to 6 SO ASTRONOMICAL JOURNAL LA English DT Article DE intergalactic medium; quasars : absorption lines; quasars : emission lines; quasars : general ID SURVEY COMMISSIONING DATA; HIGH-REDSHIFT QUASARS; SURVEY PHOTOMETRIC SYSTEM; FALL EQUATORIAL STRIPE; HOBBY-EBERLY TELESCOPE; GUNN-PETERSON TROUGH; COSMOLOGICAL REIONIZATION; INTERGALACTIC SPACE; STELLAR OBJECTS; IMAGING DATA AB We present the results from a survey of i-dropout objects selected from similar to 1550 deg(2) of multicolor imaging data from the Sloan Digital Sky Survey to search for luminous quasars at z greater than or similar to 5.8. Objects with i*-z* > 2.2 and z* < 20.2 are selected, and follow-up J-band photometry is used to separate L- and T-type cool dwarfs from high-redshift quasars. We describe the discovery of three new quasars, SDSSp J083643.85+005453.3 (z = 5.82), J130608.26+035626.3 (z = 5.99), and J103027.10+052455.0 (z = 6.28). The quasar SDSSp J083643.85+005453.3 is a radio source with flux of 1.1 mJy at 20 cm. The spectra of all three quasars show strong and broad Ly+N v emission lines and very strong Ly alpha forest absorption, with a mean continuum decrement D(A) > 0.90. The ARC 3.5 m spectrum of SDSSp J103027.10+052455.0 shows that over a range of similar to 300 Angstrom immediately blueward of the Ly alpha emission, the average transmitted flux is only 0.003 +/- 0.020 times that of the continuum level, consistent with zero flux over a similar to 300 Angstrom range of the Ly alpha forest region and suggesting a tentative detection of the complete Gunn-Peterson trough. The existence of strong metal lines in the quasar spectra suggests early metal enrichment in the quasar environment. The three new objects, together with the previously published z = 5.8 quasar SDSSp J104433.04-012502.2, form a complete color-selected flux-limited sample at z greater than or similar to 5.8. We estimate the selection function of this sample, taking into account the estimated variations in the quasar spectral energy distribution, as well as observational photometric errors. We find that at z = 6, the comoving density of luminous quasars at M(1450) < -26.8 (H(0) = 50 km s(-1) Mpc(-1), = 1) is 1.1 x 10(-9) Mpc(-3). This is a factor of similar to2 lower than that at z similar to 5 and is consistent with an extrapolation of the observed quasar evolution at z < 5. Using the current sample, we discuss the constraint on the shape of the quasar luminosity function and the implications for the contribution of quasars to the ionizing background at z 6. The luminous quasars discussed in the paper have central black hole masses of several times 10(9) M. by the Eddington argument, with likely dark halo masses on the order of 10(13) M. Their observed space density provides a sensitive test of models of quasar and galaxy formation at high redshift. C1 Inst Adv Study, Princeton, NJ 08540 USA. Princeton Univ Observ, Princeton, NJ 08544 USA. Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. Lawrence Livermore Natl Lab, IGPP, Davis, CA 95616 USA. Space Telescope Sci Inst, Baltimore, MD 21218 USA. Max Planck Inst Astron, D-69171 Heidelberg, Germany. Joint Astron Ctr, United Kingdom Infrared Telescope, Hilo, HI 96720 USA. Penn State Univ, Dept Astron & Astrophys, University Pk, PA 16802 USA. Univ Washington, Dept Astron, Seattle, WA 98195 USA. Apache Point Observ, Sunspot, NM 88349 USA. Univ Pittsburgh, Dept Phys & Astron, Pittsburgh, PA 15260 USA. Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. Eotvos Lorand Univ, Dept Phys Complex Syst, H-1117 Budapest, Hungary. Univ Tokyo, Dept Astron, Bunkyo Ku, Tokyo 1130033, Japan. Univ Tokyo, Sch Sci, Res Ctr Early Universe, Bunkyo Ku, Tokyo 1130033, Japan. Univ Tokyo, Inst Cosm Ray Res, Midori Ku, Tokyo 1888502, Japan. Gemini Observ, Hilo, HI 96720 USA. USN Observ, Washington, DC 20392 USA. Univ Chicago, Ctr Astron & Astrophys, Chicago, IL 60637 USA. USN Observ, Flagstaff Stn, Flagstaff, AZ 86002 USA. Carnegie Mellon Univ, Dept Phys, Pittsburgh, PA 15213 USA. Ctr Astron Hispano Aleman, E-04004 ALmeria, Spain. RP Fan, XH (reprint author), Inst Adv Study, Olden Lane, Princeton, NJ 08540 USA. RI Csabai, Istvan/F-2455-2012 NR 74 TC 617 Z9 619 U1 1 U2 8 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-6256 J9 ASTRON J JI Astron. J. PD DEC PY 2001 VL 122 IS 6 BP 2833 EP 2849 DI 10.1086/324111 PG 17 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 505TT UT WOS:000172932200003 ER PT J AU Becker, RH Fan, XH White, RL Strauss, MA Narayanan, VK Lupton, RH Gunn, JE Annis, J Bahcall, NA Brinkmann, J Connolly, AJ Csabai, I Czarapata, PC Doi, M Heckman, TM Hennessy, GS Ivezic, Z Knapp, GR Lamb, DQ McKay, TA Munn, JA Nash, T Nichol, R Pier, JR Richards, GT Schneider, DP Stoughton, C Szalay, AS Thakar, AR York, DG AF Becker, RH Fan, XH White, RL Strauss, MA Narayanan, VK Lupton, RH Gunn, JE Annis, J Bahcall, NA Brinkmann, J Connolly, AJ Csabai, I Czarapata, PC Doi, M Heckman, TM Hennessy, GS Ivezic, Z Knapp, GR Lamb, DQ McKay, TA Munn, JA Nash, T Nichol, R Pier, JR Richards, GT Schneider, DP Stoughton, C Szalay, AS Thakar, AR York, DG TI Evidence for reionization at z similar to 6: Detection of a Gunn-Peterson trough in a z=6.28 quasar SO ASTRONOMICAL JOURNAL LA English DT Article DE cosmology : observations; galaxies : formation; quasars : absorption lines; quasars : general ID LY-ALPHA FOREST; DIGITAL SKY SURVEY; SPECTROPHOTOMETRIC STANDARDS; INTERGALACTIC SPACE; REDSHIFT QUASARS; EVOLUTION; DENSITY; HYDROGEN; SPECTRA; FLUX AB We present moderate-resolution Keck spectroscopy of quasars at z = 5.82, 5.99, and 6.28, discovered by the Sloan Digital Sky Survey (SDSS). We find that the Ly alpha absorption in the spectra of these quasars evolves strongly with redshift. To z similar to 5.7, the Ly alpha absorption evolves as expected from an extrapolation from lower redshifts. However, in the highest-redshift object, SDSSp J103027.10+052455.0 (z = 6.28), the average transmitted flux is 0.0038 +/- 0.0026 times that of the continuum level over 8450 Angstrom < < 8710 (5.95 < z(abs) < 6.16), consistent with zero flux. Thus the flux level drops by a factor of greater than 150 and is consistent with zero flux in the Ly alpha forest region immediately blueward of the Ly alpha emission line, compared with a drop by a factor of similar to 10 at z(abs) similar to 5.3. A similar break is seen at Ly beta; because of the decreased oscillator strength of this transition, this allows us to put a considerably stronger limit, tau (eff) > 20, on the optical depth to Ly alpha absorption at z = 6. This is a clear detection of a complete Gunn-Peterson trough, caused by neutral hydrogen in the intergalactic medium. Even a small neutral hydrogen fraction in the intergalactic medium would result in an undetectable flux in the Ly alpha forest region. Therefore, the existence of the Gunn-Peterson trough by itself does not indicate that the quasar is observed prior to the reionization epoch. However, the fast evolution of the mean absorption in these high-redshift quasars suggests that the mean ionizing background along the line of sight to this quasar has declined significantly from z similar to 5 to 6, and the universe is approaching the reionization epoch at z similar to 6. C1 Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. Lawrence Livermore Natl Lab, IGPP, Livermore, CA 94550 USA. Inst Adv Study, Princeton, NJ 08540 USA. Space Telescope Sci Inst, Baltimore, MD 21218 USA. Princeton Univ Observ, Princeton, NJ 08544 USA. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Apache Point Observ, Sunspot, NM 88349 USA. Univ Pittsburgh, Dept Phys & Astron, Pittsburgh, PA 15260 USA. Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. Eotvos Lorand Univ, Dept Phys Complex Syst, H-1117 Budapest, Hungary. Univ Tokyo, Sch Sci, Res Ctr Early Universe, Bunkyo Ku, Tokyo 1130033, Japan. Univ Tokyo, Dept Astron, Bunkyo Ku, Tokyo 1130033, Japan. USN Observ, Washington, DC 20392 USA. Univ Chicago, Ctr Astron & Astrophys, Chicago, IL 60637 USA. Univ Michigan, Dept Phys, Ann Arbor, MI 48109 USA. USN Observ, Flagstaff Stn, Flagstaff, AZ 86002 USA. Carnegie Mellon Univ, Dept Phys, Pittsburgh, PA 15232 USA. Penn State Univ, Dept Astron & Astrophys, University Pk, PA 16802 USA. Univ Chicago, Enrico Fermi Inst, Chicago, IL 60637 USA. RP Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. RI Csabai, Istvan/F-2455-2012; McKay, Timothy/C-1501-2009 OI McKay, Timothy/0000-0001-9036-6150 NR 32 TC 671 Z9 673 U1 0 U2 7 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-6256 EI 1538-3881 J9 ASTRON J JI Astron. J. PD DEC PY 2001 VL 122 IS 6 BP 2850 EP 2857 DI 10.1086/324231 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 505TT UT WOS:000172932200004 ER PT J AU Henry, GW Fekel, FC Kaye, AB Kaul, A AF Henry, GW Fekel, FC Kaye, AB Kaul, A TI 10 new gamma Doradus and delta Scuti stars SO ASTRONOMICAL JOURNAL LA English DT Article DE delta Scuti; stars : early-type; stars : fundamental parameters; stars : oscillations; stars : variables : other ID GROUND-BASED MEASUREMENTS; DOUBLE-MODE CEPHEIDS; SUN-LIKE STARS; RADIAL-VELOCITIES; PHOTOMETRIC VARIABILITY; ROTATIONAL VELOCITIES; HIPPARCOS; VARIABLES; CLASSIFICATION; SPECTROSCOPY AB We present high-resolution spectroscopy and precision photometry of five new gamma Doradus and five new delta Scuti variables. The five new gamma Doradus variables substantially increase the number of confirmed stars of this class. All 10 stars fall in the spectral class range F0-F2, but they are cleanly separated into two groups by their luminosity and photometric periods. However, the period gap between the gamma Doradus and delta Scuti stars is becoming very narrow since we confirm that HD 155154 is a gamma Doradus star with the shortest periods reported to date (the shortest of its four periods is similar to0.312 days). We do not find any evidence in our sample for stars exhibiting both delta Scuti- and gamma Doradus-type pulsations. C1 Tennessee State Univ, Ctr Excellence Informat Syst, Nashville, TN 37203 USA. Los Alamos Natl Lab, Div Appl Phys, Los Alamos, NM 87545 USA. RP Henry, GW (reprint author), Tennessee State Univ, Ctr Excellence Informat Syst, 330 10th Ave N, Nashville, TN 37203 USA. NR 53 TC 35 Z9 35 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-6256 J9 ASTRON J JI Astron. J. PD DEC PY 2001 VL 122 IS 6 BP 3383 EP 3395 DI 10.1086/324228 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 505TT UT WOS:000172932200040 ER PT J AU Smith, GP Treu, T Ellis, R Smail, I Kneib, JP Frye, BL AF Smith, GP Treu, T Ellis, R Smail, I Kneib, JP Frye, BL TI Near-infrared spectroscopy and Hubble Space Telescope imaging of a dusty starburst Extremely Red Object SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : evolution; galaxies : high-redshift; galaxies : individual (ERO J164023+4644.0); galaxies : starburst; infrared : galaxies ID STAR-FORMATION; ULTRALUMINOUS GALAXY; HIGH-REDSHIFT; CLUSTERS; ULTRAVIOLET; SEARCH; FIELD; SCUBA AB We present near-infrared spectroscopy and Hubble Space Telescope (HST) imaging of ERO J164023 + 4644, an Extremely Red Object (ERO) with (R-K) = 5.9 at z = 1.05 that has been detected by Infrared Space Observatory (ISO) at 15 mum. ERO J164023 resembles a disk galaxy, with an optical/infrared spectral energy distribution that is strongly reddened by dust (L-FIR/L-B less than or similar to 200; A(V) similar to 5). The combination of the narrow width of the emission lines in our spectra (similar to 300 km s(-1)) and the relatively high [N II]/H alpha line ratio indicate that this is a "composite" starburst-Seyfert galaxy. Assuming that star formation dominates the energy output, we constrain the star formation rate to lie in the broad range similar to 10-700 M. yr(-1) from a variety of star formation indicators. We compare ERO J164023 with the only other spectroscopically identified dusty EROs: HR10 (z = 1.44) and ISO J1324-2016 (z = 1.50). ERO J164023 and HR10 have similar disklike morphologies in the rest-frame UV, and both exhibit a variation in the apparent dust obscuration depending upon the diagnostic used, which suggests that there is a complex spatial mix of stellar populations and dust in these galaxies. In contrast, the compact morphology and spectral properties of ISO J1324-2016 indicate that it is a dusty quasar. Overall, our results demonstrate that the population of dusty galaxies identified using photometric ERO criteria includes systems ranging from pure starbursts through transition systems, such as ERO J164023, to dusty quasars. We suggest that the classification of EROs into these subclasses, necessary for the detailed modeling of the population, cannot be reliably achieved from optical/near-infrared photometry and instead requires mid/far-infrared or submillimeter photometry and near-infrared spectroscopy. The advent of efficient multiobject spectrographs working in the near-infrared, as well as the imminent launch of SIRTF, therefore promises the opportunity of rapid progress in our understanding of the elusive ERO population. C1 Univ Durham, Dept Phys, Durham DH1 3LE, England. CALTECH, Dept Astron, Pasadena, CA 91125 USA. Observ Midi Pyrenees, CNRS, UMR 5572, F-31400 Toulouse, France. Univ Calif Berkeley, Lawrence Berkeley Lab, Dept Phys, Berkeley, CA 94720 USA. RP Smith, GP (reprint author), Univ Durham, Dept Phys, South Rd, Durham DH1 3LE, England. RI Smail, Ian/M-5161-2013; Kneib, Jean-Paul/A-7919-2015 OI Smail, Ian/0000-0003-3037-257X; Kneib, Jean-Paul/0000-0002-4616-4989 NR 31 TC 22 Z9 22 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD DEC 1 PY 2001 VL 562 IS 2 BP 635 EP 640 DI 10.1086/323878 PN 1 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 499LL UT WOS:000172572600006 ER PT J AU Grosdidier, Y Moffat, AFJ Blais-Ouellette, S Joncas, G Acker, A AF Grosdidier, Y Moffat, AFJ Blais-Ouellette, S Joncas, G Acker, A TI Hubble Space Telescope imagery and Canada-France-Hawaii Telescope Fabry-Perot two-dimensional spectroscopy in H alpha of the ejected nebula M1-67: Turbulent status SO ASTROPHYSICAL JOURNAL LA English DT Article DE ISM : bubbles; ISM : individual (M1-67); ISM : kinematics and dynamics; stars : individual (WR 124); stars : Wolf-Rayet; turbulence ID WOLF-RAYET STARS; SPATIALLY RESOLVED SPECTROSCOPY; WR RING NEBULAE; MOLECULAR CLOUDS; FUNDAMENTAL PARAMETERS; PLANETARY-NEBULAE; WAVELET ANALYSIS; WIND INHOMOGENEITIES; INTERSTELLAR-MEDIUM; VELOCITY-FIELDS AB Bright circumstellar nebulae around massive stars are potentially useful to derive time-dependent mass-loss rates and hence constrain the evolution of the central stars. A key case in this context is the relatively young ejection-type nebula M1-67 around the runaway Population I Wolf-Rayet star WR 124 (=209 BAC), which exhibits a WN 8 spectrum. With HST-WFPC2 we have obtained a deep, H alpha image of M1-67. This image shows a wealth of complex detail that was briefly presented previously by Grosdidier et al. With the interferometer of the Universite Laval (Quebec, Canada), we have obtained complementary Fabry-Perot Ha data using Canada-France-Hawaii Telescope (CFHT) MOS/SIS. From these data M1-67 appears more or less as a spherical (or elliptical, with the major axis along the line of sight), thick, shell seen almost exactly along its direction of rapid spatial motion away from the observer in the ISM. However, a simple thick shell by itself would not explain the observed multiple radial velocities along the line of sight. This velocity dispersion leads one to consider M1-67 as a thick accelerating shell. Given the extreme perturbations of the velocity field in M1-67, it is virtually impossible to measure any systematic impact of the present WR (or previous LBV) wind on the nebular structure. The irregular nature of the velocity field is likely due to either large variations in the density distribution of the ambient ISM or large variations in the central star mass-loss history. In addition, either from the density field or the velocity field, we find no clear evidence for a bipolar outflow, as was claimed in other studies. On the deep H alpha image we have performed continuous wavelet transforms to isolate stochastic structures of different characteristic size and look for scaling laws. Small-scale wavelet coefficients show that the density field of M1-67 is remarkably structured in chaotically (or possibly radially) oriented filaments everywhere in the nebula. We draw attention to a short, marginally inertial range at the smallest scales (6.7-15.0 x 10(-3) pc), which can be attributed to turbulence in the nebula, and a strong scale break at larger scales. Examination of the structure functions for different orders shows that the turbulent regime may be intermittent. Using our Fabry-Perot interferograms, we also present an investigation of the statistical properties of fluctuating gas motions using structure functions traced by H alpha emission-line centroid velocities. We find that there is a clear correlation at scales 0.02-0.22 pc between the mean quadratic differences of radial velocities and distance over the surface of the nebula. This implies that the velocity field shows an inertial range likely related to turbulence, though not coincident with the small inertial range detected from the density field. The first- and second-order moments of the velocity increments are found to scale as [\Deltav(r)\] similar to r(0.5) and [\Deltav(r)\(2)] similar to r(0.9). The former scaling law strongly suggests that supersonic, compressible turbulence is at play in the nebula; on the other hand, the latter scaling law agrees very well with Larson-type laws for velocity turbulence. Examination of the structure functions for different orders shows that the turbulent regime is slightly intermittent and highly multifractal with universal multifractal indexes alpha approximate to 1.90-1.92 and C-1 approximate to 0.04 +/- 0.01. C1 Observ Astron Mt Megantic, Montreal, PQ, Canada. Observ Astron, UMR 7550, F-97000 Strasbourg, France. Univ Montreal, Dept Phys, Montreal, PQ H3C 3J7, Canada. Lawrence Livermore Natl Lab, Inst Geophys & Planetary Phys, Livermore, CA 94550 USA. Univ Laval, Dept Phys, St Foy, PQ G1K 7P4, Canada. RP Grosdidier, Y (reprint author), Inst Astrofis Canarias, Calle Via Lactea S-N, E-38200 La Laguna, Tenerife, Spain. NR 88 TC 18 Z9 18 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD DEC 1 PY 2001 VL 562 IS 2 BP 753 EP 769 DI 10.1086/323357 PN 1 PG 17 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 499LL UT WOS:000172572600017 ER PT J AU Gunderson, K Wilkinson, E Green, JC Barstow, MA AF Gunderson, K Wilkinson, E Green, JC Barstow, MA TI Extreme-ultraviolet rocket spectroscopy of the hot DA white dwarf G191-B2B SO ASTROPHYSICAL JOURNAL LA English DT Article DE instrumentation : spectrographs; stars : individual (G191-B2B); ultraviolet : stars; white dwarfs ID RADIATIVE LEVITATION; PARAMETER-ESTIMATION; OPACITY PROJECT; HEAVY-ELEMENTS; ATMOSPHERES; ABUNDANCES; DIFFUSION; ASTRONOMY; DISCOVERY; SPECTRA AB Because of a lack of spectral resolution in existing spectroscopic data, current white dwarf atmospheric models cannot explain the atmospheric structure, and resultant extreme-ultraviolet (EUV) emission, of G191-B2B unambiguously. Therefore, a new rocket-borne EUV spectrograph was designed, built, calibrated, and launched. This instrument observed G191-B2B over a bandpass of 254E317 Angstrom and with a resolving power of lambda/Delta lambda approximate to 2800. Highly statistically significant absorption features within the flight spectrum, coupled with metal-rich modeled stellar spectra, provide evidence for blended features of Fe IV / Fe V and Fe IV / O III in G191-B2B's atmosphere. A 3 sigma upper limit of 2 x 10(-5) has been placed on the photospheric helium abundance, arguing against models that rely on He II as a major EUV opacity source. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Colorado, Boulder, CO 80309 USA. Univ Leicester, Dept Phys & Astron, Leicester LE1 7RH, Leics, England. RP Gunderson, K (reprint author), Lawrence Livermore Natl Lab, 7000 East Ave L-413, Livermore, CA 94550 USA. NR 39 TC 3 Z9 3 U1 1 U2 2 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD DEC 1 PY 2001 VL 562 IS 2 BP 992 EP 997 DI 10.1086/323838 PN 1 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 499LL UT WOS:000172572600037 ER PT J AU Eggleton, PP Kiseleva-Eggleton, L AF Eggleton, PP Kiseleva-Eggleton, L TI Orbital evolution in binary and triple stars, with an application to SS Lacertae SO ASTROPHYSICAL JOURNAL LA English DT Article DE binaries : general; celestial mechanics; stars : evolution; stars : individual (SS Lacertae) ID CLOSE BINARY; TIDAL EVOLUTION; INTRINSIC KICKS; NEUTRON-STARS; RADIO PULSAR; FRICTION; SYSTEMS; BIRTH; ECLIPSES; EXPLAIN AB We present equations governing the way in which both the orbit and the intrinsic spins of stars in a close binary should evolve subject to a number of perturbing forces, including the effect of a third body in a possibly inclined wider orbit. We illustrate the solutions in some binary star and triple star situations: tidal friction in a wide but eccentric orbit of a radio pulsar about a B star (0045-7319), the Darwin and eccentricity instabilities in a more massive but shorter period massive X-ray binary, and the interaction of tidal friction with Kozai cycles in a triple star, such as beta Per at an early stage in that star's life, when all three components were zero-age main sequence stars. We also attempt to model in some detail the interesting triple system SS Lac, which stopped eclipsing in about 1950. We find that our model of SS Lac is quite constrained by the relatively good observational data of this system and leads to a specific inclination (29 degrees) of the outer orbit relative to the inner orbit at epoch zero (1912). We make some predictions about changes to system parameters in the short term (20-40 yr) and also in the medium term (up to similar to 3000 yr). Although the intrinsic spins of the stars have little effect on the orbit, the converse is not true: the spin axes can vary their orientation relative to the close binary by up to 120 degrees on a timescale of about a century. C1 Lawrence Livermore Natl Lab, Inst Geophys & Planetary Phys, Livermore, CA 94550 USA. RP Eggleton, PP (reprint author), Lawrence Livermore Natl Lab, Inst Geophys & Planetary Phys, POB 808,L-413, Livermore, CA 94550 USA. NR 27 TC 158 Z9 158 U1 1 U2 3 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD DEC 1 PY 2001 VL 562 IS 2 BP 1012 EP 1030 DI 10.1086/323843 PN 1 PG 19 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 499LL UT WOS:000172572600039 ER PT J AU Weaver, AJ Eby, M Wiebe, EC Bitz, CM Duffy, PB Ewen, TL Fanning, AF Holland, MM MacFadyen, A Matthews, HD Meissner, KJ Saenko, O Schmittner, A Wang, HX Yoshimori, M AF Weaver, AJ Eby, M Wiebe, EC Bitz, CM Duffy, PB Ewen, TL Fanning, AF Holland, MM MacFadyen, A Matthews, HD Meissner, KJ Saenko, O Schmittner, A Wang, HX Yoshimori, M TI The UVic Earth System Climate Model: Model description, climatology, and applications to past, present and future climates SO ATMOSPHERE-OCEAN LA English DT Review ID LAST-GLACIAL-MAXIMUM; GENERAL-CIRCULATION MODEL; SEA-SURFACE TEMPERATURE; ATLANTIC THERMOHALINE CIRCULATION; OCEAN-ATMOSPHERE MODEL; DEEP-WATER FLUX; ICE-SHEET; SOUTHERN-OCEAN; INTERMEDIATE COMPLEXITY; THICKNESS DISTRIBUTION AB A new earth system climate model of intermediate complexity has been developed and its climatology compared to observations. The UVic Earth System Climate Model consists of a three-dimensional ocean general circulation model coupled to a thermodynamic/dynamic sea-ice model, an energy-moisture balance atmospheric model with dynamical feedbacks, and a thermomechanical land-ice model. In order to keep the model computationally efficient a reduced complexity atmosphere model is used. Atmospheric heat and freshwater transports are parametrized through Fickian diffusion, and precipitation is assumed to occur when the relative humidity is greater than 85%. Moisture transport can also be accomplished through advection if desired. Precipitation over land is assumed to return instantaneously to the ocean via one of 33 observed river drainage basins. Ice and snow albedo feedbacks are included in the coupled model by locally increasing the prescribed latitudinal profile of the planetary albedo. The atmospheric model includes a parametrization of water vapour/planetary longwave feedbacks, although the radiative forcing associated with changes in atmospheric CO2 is prescribed as a modification of the planetary longwave radiative flux. A specified lapse rate is used to reduce the surface temperature over land where there is topography. The model uses prescribed present-day winds in its climatology, although a dynamical wind feedback is included which exploits a latitudinally-varying empirical relationship between atmospheric surface temperature and density. The ocean component of the coupled model is based on the Geophysical Fluid Dynamics Laboratory (GFDL) Modular Ocean Model 2.2, with a global resolution of 3.6degrees (zonal) by 1.8degrees (meridional) and 19 vertical levels, and includes an option for brine-rejection parametrization. The sea-ice component incorporates an elastic-viscous-plastic rheology to represent sea-ice dynamics and various options for the representation of sea-ice thermodynamics and thickness distribution. The systematic comparison of the coupled model with observations reveals good agreement, especially when moisture transport is accomplished through advection. Global warming simulations conducted using the model to explore the role of moisture advection reveal a climate sensitivity of 3.0degreesC for a doubling of CO2, in line with other more comprehensive coupled models. Moisture advection, together with the wind feedback, leads to a transient simulation in which the meridional overturning in the North Atlantic initially weakens, but is eventually re-established to its initial strength once the radiative forcing is held fixed, as found in many coupled atmosphere General Circulation Models (GCMs). This is in contrast to experiments in which moisture transport is accomplished through diffusion whereby the overturning is re-established to a strength that is greater than its initial condition. When applied to the climate of the Last Glacial Maximum (LGM), the model obtains tropical cooling (30degreesN-30degreesS), relative to the present, of about 2.1degreesC over the ocean and 3.6degrees C over the land. These are generally cooler than CLIMAP estimates, but not as cool as some other reconstructions. This moderate cooling is consistent with alkenone reconstructions and a low to medium climate sensitivity to perturbations in radiative forcing. An amplification of the cooling occurs in the North Atlantic due to the weakening of North Atlantic Deep Water formation. Concurrent with this weakening is a shallowing of, and a more northward penetration of, Antarctic Bottom Water. Climate models are usually evaluated by spinning them up under perpetual present-day forcing and comparing the model results with present-day observations. Implicit in this approach is the assumption that the present-day observations are in equilibrium with the present-day radiative forcing. The comparison of a long transient integration (starting at 6 KBP), forced by changing radiative forcing (solar, CO2, orbital), with an equilibrium integration reveals substantial differences. Relative to the climatology from the present-day equilibrium integration, the global mean surface air and sea surface temperatures (SSTs) are 0.74degreesC and 0.55degreesC colder, respectively. Deep ocean temperatures are substantially cooler and southern hemisphere sea-ice cover is 22% greater, although the North Atlantic conveyor remains remarkably stable in all cases. The differences are due to the long timescale memory of the deep ocean to climatic conditions which prevailed throughout the late Holocene. It is also demonstrated that a global warming simulation that starts from an equilibrium present-day climate (cold start) underestimates the global temperature increase at 2100 by 13% when compared to a transient simulation, under historical solar, CO2 and orbital forcing, that is also extended out to 2100. This is larger (13% compared to 9.8%) than the difference from an analogous transient experiment which does not include historical changes in solar forcing. These results suggest that those groups that do not account for solar forcing changes over the twentieth century may slightly underestimate (similar to3% in our model) the projected warming by the year 2100. C1 Univ Victoria, Sch Earth & Ocean Sci, Victoria, BC V8W 3P6, Canada. Polar Sci Ctr, Appl Phys Lab, Seattle, WA USA. Natl Ctr Atmospher Res, Boulder, CO 80307 USA. Lawrence Livermore Natl Lab, Livermore, CA USA. RP Weaver, AJ (reprint author), Univ Victoria, Sch Earth & Ocean Sci, POB 3055, Victoria, BC V8W 3P6, Canada. RI Schmittner, Andreas/A-3101-2008; Matthews, Damon/A-8965-2008; Weaver, Andrew/E-7590-2011; Eby, Michael/H-5278-2013; Wiebe, Edward/E-5532-2015; Schmittner, Andreas/O-9647-2015; Bitz, Cecilia/S-8423-2016 OI Wiebe, Edward/0000-0003-1583-6209; Schmittner, Andreas/0000-0002-8376-0843; Bitz, Cecilia/0000-0002-9477-7499 NR 139 TC 345 Z9 348 U1 5 U2 65 PU CANADIAN METEOROLOGICAL OCEANOGRAPHIC SOC PI OTTAWA PA 150 LOUIS PASTEUR PVT., STE 112, MCDONALD BUILDING, OTTAWA, ONTARIO K1N 6N5, CANADA SN 0705-5900 J9 ATMOS OCEAN JI Atmos.-Ocean PD DEC PY 2001 VL 39 IS 4 BP 361 EP 428 PG 68 WC Meteorology & Atmospheric Sciences; Oceanography SC Meteorology & Atmospheric Sciences; Oceanography GA 514MZ UT WOS:000173445700001 ER PT J AU Vuilleumier, L Bamer, JT Harley, RA Brown, NJ AF Vuilleumier, L Bamer, JT Harley, RA Brown, NJ TI Evaluation of nitrogen dioxide photolysis rates in an urban area using data from the 1997 Southern California Ozone Study SO ATMOSPHERIC ENVIRONMENT LA English DT Article DE NO2 photolysis; actinometry; radiative transfer model; aerosol ID ABSORPTION CROSS-SECTIONS; OBSERVATORY PHOTOCHEMISTRY EXPERIMENT; VOLATILE ORGANIC-COMPOUNDS; PHASE CHEMICAL MECHANISM; SENSITIVITY ANALYSIS; RATE COEFFICIENT; UNCERTAINTY ANALYSIS; FIRST-ORDER; NO2; ATMOSPHERES AB The photolysis of nitrogen dioxide and formaldehyde are two of the most influential reactions in the formation of photochemical air pollution, and their rates are computed using actinic flux determined from a radiative transfer model. In this study, we compare predicted and measured nitrogen dioxide photolysis rate coefficients (j(NO2)). We used the Tropospheric Ultraviolet-Visible (TUV) radiation transfer model to predict j(NO2) values corresponding to measurements performed in Riverside, California as part of the 1997 Southern California Ozone Study (SCOS'97). Spectrally resolved irradiance measured at the same site allowed us to determine atmospheric optical properties, such as aerosol optical depth and total ozone column, that are needed as inputs for the radiative transfer model. Matching measurements of aerosol optical depth, ozone column, and j(NO2) were obtained for 14 days during SCOS'97. By using collocated measurements of the light extinction caused by aerosols and ozone over the full height of the atmosphere as model input, it was possible to predict sudden changes in j(NO2) resulting from atmospheric variability. While the diurnal profile of the rate coefficient was readily reproduced, j(NO2) model predicted values were found to be consistently higher than measured values. The bias between measured and predicted values was 17-36%, depending on the assumed single scattering albedo. By statistical analysis, we restricted the most likely values of the single scattering albedo to a range that produced bias on the order of 20-25%. It is likely that measurement error is responsible for a significant part of the bias. The aerosol single scattering albedo was found to be a major source of uncertainty in radiative transfer model predictions. Our best estimate indicates its average value at UV-wavelengths for the period of interest is between 0.77 and 0.85. Published by Elsevier Science Ltd. C1 Lawrence Berkeley Natl Lab, Environm Energy Technol Div, Berkeley, CA 94720 USA. Univ Calif Davis, Dept Civil & Environm Engn, Berkeley, CA 94720 USA. RP Vuilleumier, L (reprint author), Lawrence Berkeley Natl Lab, Environm Energy Technol Div, 1 Cyclotron Rd,29C, Berkeley, CA 94720 USA. RI Harley, Robert/C-9177-2016 OI Harley, Robert/0000-0002-0559-1917 NR 48 TC 11 Z9 11 U1 0 U2 5 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 2001 VL 35 IS 36 BP 6525 EP 6537 DI 10.1016/S1352-2310(01)00379-X PG 13 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA 507VQ UT WOS:000173052300025 ER PT J AU Badger, P AF Badger, P TI Trends and progress in US bioenergy technologies SO BIOCYCLE LA English DT Article C1 Gen Bioenergy Inc, Florence, AL USA. US DOE, SE Reg Biomass Energy Program, Washington, DC 20585 USA. RP Badger, P (reprint author), Gen Bioenergy Inc, Florence, AL USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU JG PRESS, INC PI EMMAUS PA 419 STATE AVE, EMMAUS, PA 18049 USA SN 0276-5055 J9 BIOCYCLE JI Biocycle PD DEC PY 2001 VL 42 IS 12 BP 36 EP 41 PG 6 WC Ecology; Soil Science SC Environmental Sciences & Ecology; Agriculture GA 504BQ UT WOS:000172837700039 ER PT J AU Kim, SH Marmo, C Somorjai, GA AF Kim, SH Marmo, C Somorjai, GA TI Friction studies of hydrogel contact lenses using AFM: non-crosslinked polymers of low friction at the surface SO BIOMATERIALS LA English DT Article DE contact lens; hydrogel; poly(2-hydroxyethyl methacrylate); AFM; friction ID ATOMIC-FORCE MICROSCOPY; HUMAN SERUM-ALBUMIN; POLY(2-HYDROXYETHYL METHACRYLATE); BACTERIAL ADHESION; IN-VITRO; WATER; ADSORPTION; WETTABILITY; REARRANGEMENT; SPECTROSCOPY AB The surface of soft contact lenses made of crosslinked poly(2-hydroxyethyl methacrylate), pHEMA, has been investigated with atomic force microscopy in contact mode. The friction force and adhesive force measurements were able to differentiate the non-crosslinked pHEMA chains from the surface of the crosslinked pHEMA networks. These non-crosslinked pHEMA chains at the surface were anchored to the crosslinked pHEMA network, most likely by entanglement and their surfaces were about 2-4 nm higher than the surrounding surface in a dehydrated state. In saline solution, the surface friction and adhesive force of the contact lens were significantly reduced compared to those measured for the surface-dehydrated contact lens. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Ocular Sci Inc, San Francisco, CA 94080 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Somorjai, GA (reprint author), Univ Calif Berkeley, Dept Chem, D58 Hildebrand Hall 1460, Berkeley, CA 94720 USA. NR 42 TC 37 Z9 38 U1 2 U2 24 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0142-9612 J9 BIOMATERIALS JI Biomaterials PD DEC PY 2001 VL 22 IS 24 SI SI BP 3285 EP 3294 DI 10.1016/S0142-9612(01)00175-2 PG 10 WC Engineering, Biomedical; Materials Science, Biomaterials SC Engineering; Materials Science GA 485NB UT WOS:000171759500009 PM 11700800 ER PT J AU Lin, YH Timchalk, CA Matson, DW Wu, H Thrall, KD AF Lin, Yuehe Timchalk, Charles A. Matson, Dean W. Wu, Hong Thrall, Karla D. TI Integrated Microfluidics/Electrochemical Sensor System for Monitoring of Environmental Exposures to Lead and Chlorophenols SO BIOMEDICAL MICRODEVICES LA English DT Article DE microfluidics; electrochemical sensor; lead; chlorophenols; biomonitoring AB A microanalytical system based on a microfluidics/electrochemical detection scheme was developed. The microfluidic platform was fabricated based on a multi-layer lamination method. Fluidic microchannels were produced by sandwiching laser-machined adhesive-backed polyimide gaskets between layers of the device. Individual components, such as microfabricated piezo-electrically actuated pumps and a microelectrochemical cell were designed and fabricated into plug-in modules which can be readily plugged into (or unplugged from) the microfluidic platform. This allowed rapid change-out and repair of individual components by incorporating "plug and play" concepts now standard in PC's. The detection of lead and chlorophenols were performed with the microanalytical system to demonstrate the capabilities of this new technology for on-site environmental characterization and for real-time non-invasive biomonitoring of toxic chemical mixtures. C1 [Lin, Yuehe; Timchalk, Charles A.; Matson, Dean W.; Wu, Hong; Thrall, Karla D.] Pacific NW Natl Lab, Richland, WA 99352 USA. RP Lin, YH (reprint author), Pacific NW Natl Lab, POB 999, Richland, WA 99352 USA. RI Lin, Yuehe/D-9762-2011 OI Lin, Yuehe/0000-0003-3791-7587 FU US DOE through a laboratory directed research and development (LDRD) program at the Pacific Northwest National Laboratory (PNNL); US DOE [DE-AC06-76RLO 1830] FX The authors would like to thank Dr. I.F. Cheng at the University of Idaho for the development of dechlorination reaction for chlorophenols and Wendy. D. Bennett for help in microfabrication. We also acknowledge Dr. Joe Pounds and Mr. Kelvin Soldat for helpful discussions and strong support throughout this work. This project was supported by US DOE through a laboratory directed research and development (LDRD) program at the Pacific Northwest National Laboratory (PNNL). PNNL is operated by Battelle Memorial Institute for the US DOE under Contract DE-AC06-76RLO 1830. NR 23 TC 23 Z9 24 U1 0 U2 4 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 1387-2176 EI 1572-8781 J9 BIOMED MICRODEVICES JI Biomed. Microdevices PD DEC PY 2001 VL 3 IS 4 BP 331 EP 338 DI 10.1023/A:1012417000516 PG 8 WC Engineering, Biomedical; Nanoscience & Nanotechnology SC Engineering; Science & Technology - Other Topics GA V33KX UT WOS:000209018800010 ER PT J AU Facciotti, MT Rouhani, S Burkard, FT Betancourt, FM Downing, KH Rose, RB McDermott, G Glaeser, RM AF Facciotti, MT Rouhani, S Burkard, FT Betancourt, FM Downing, KH Rose, RB McDermott, G Glaeser, RM TI Structure of an early intermediate in the M-state phase of the bacteriorhodopsin photocycle SO BIOPHYSICAL JOURNAL LA English DT Article ID X-RAY-DIFFRACTION; LIPIDIC CUBIC PHASES; PROTON TRANSLOCATION; MACROMOLECULAR STRUCTURES; ANGSTROM RESOLUTION; MEMBRANE-PROTEINS; CRYSTALLIZATION; TRANSPORT; DISPLAY; MODEL AB The structure of an early M-intermediate of the wild-type bacteriorhodopsin photocycle formed by actinic illumination at 230 K has been determined by x-ray crystallography to a resolution of 2.0 Angstrom. Three-imensional crystals were trapped by illuminating with actinic light at 230 K, followed by quenching in liquid nitrogen. Amide I, amide II, and other infrared absorption bands, recorded from single bacteriorhodopsin crystals, confirm that the M-substate formed represents a structure that occurs early after deprotonation of the Schiff base. Rotation about the retinal C13-C14 double bond appears to be complete, but a relatively large torsion angle of 26 degrees is still seen for the C14-C15 bond. The intramolecular stress associated with the isomerization of retinal and the subsequent deprotonation of the Schiff base generates numerous small but experimentally measurable structural changes within the protein. Many of the residues that are displaced during the formation of the late M (M,) substate, formed by three-dimensional crystals of the D96N mutant (Luecke et al., 1999b) are positioned, in early M, between their resting-state locations and the ones which they will adopt at the end of the M phase. The relatively small magnitude of atomic displacements observed in this intermediate, and the well-defined positions adopted by nearly all of the atoms in the structure, may make the formation of this structure favorable to model (simulate) by molecular dynamics. C1 Lawrence Berkeley Natl Lab, Grad Grp Biophys, Berkeley, CA 94720 USA. Lawrence Berkeley Natl Lab, Life Sci Div, Berkeley, CA 94720 USA. Lawrence Berkeley Natl Lab, Phys Biosci Div, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Macromol Crystallog Facil, Berkeley, CA 94720 USA. Dept Mol & Cell Biol, Stanley Donner ASU 3206, Berkeley, CA 94720 USA. RP Glaeser, RM (reprint author), Lawrence Berkeley Natl Lab, Grad Grp Biophys, 363 Donner Lab, Berkeley, CA 94720 USA. FU NIGMS NIH HHS [GM08295, GM51487] NR 42 TC 96 Z9 96 U1 1 U2 2 PU BIOPHYSICAL SOCIETY PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0006-3495 J9 BIOPHYS J JI Biophys. J. PD DEC PY 2001 VL 81 IS 6 BP 3442 EP 3455 PG 14 WC Biophysics SC Biophysics GA 496QQ UT WOS:000172407800037 PM 11721006 ER PT J AU Gilbert, JR Li, XS Ng, EG Peyton, BW AF Gilbert, JR Li, XS Ng, EG Peyton, BW TI Computing row and column counts for sparse QR and LU factorization SO BIT LA English DT Article DE sparse QR and LU factorizations; column elimination tree; row and column counts; disjoint set union ID GAUSSIAN-ELIMINATION; ALGORITHMS; MATRIX; IMPLEMENTATION; TREES AB We present algorithms to determine the number of nonzeros in each row and column of the factors of a sparse matrix, for both the QR factorization and the LU factorization with partial pivoting. The algorithms use only the nonzero structure of the input matrix, and run in time nearly linear in the number of nonzeros in that matrix. They may be used to set up data structures or schedule parallel operations in advance of the numerical factorization. The row and column counts we compute are upper bounds on the actual counts. If the input matrix is strong Hall and there is no coincidental numerical cancellation, the counts axe exact for QR factorization and are the tightest bounds possible for LU factorization. These algorithms are based on our earlier work on computing row and column counts for sparse Cholesky factorization, plus an efficient method to compute the column elimination tree of a sparse matrix without explicitly forming the product of the matrix and its transpose. C1 Xerox Corp, Palo Alto Res Ctr, Palo Alto, CA 94304 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Natl Energy Res Sci Comp Div, Berkeley, CA 94720 USA. Oak Ridge Natl Lab, Div Math & Comp Sci, Oak Ridge, TN 37831 USA. NR 27 TC 8 Z9 9 U1 0 U2 1 PU SWETS ZEITLINGER PUBLISHERS PI LISSE PA P O BOX 825, 2160 SZ LISSE, NETHERLANDS SN 0006-3835 J9 BIT JI Bit PD DEC PY 2001 VL 41 IS 4 BP 693 EP 710 DI 10.1023/A:1021943902025 PG 18 WC Computer Science, Software Engineering; Mathematics, Applied SC Computer Science; Mathematics GA 522QU UT WOS:000173909100005 ER PT J AU Buttler, WT Soriano, C Baldasano, JM Nickel, GH AF Buttler, WT Soriano, C Baldasano, JM Nickel, GH TI Remote sensing of three-dimensional winds with elastic lidar: Explanation of maximum cross-correlation method SO BOUNDARY-LAYER METEOROLOGY LA English DT Article DE lidar; maximum cross-correlation method; mesoscale meteorology; remote wind sensing ID PLANETARY BOUNDARY-LAYER; SURFACE VELOCITIES; PROFILES AB Maximum cross-correlation provides a method to remotely determine highly resolved three-dimensional fields of horizontal winds with elastic lidar through-out large volumes of the planetary boundary layer (PBL). This paper details the technique and shows comparisons between elastic lidar winds, remotely sensed laser Doppler velocimeter (LDV) wind profiles, and radiosonde winds. Radiosonde wind data were acquired at Barcelona, Spain, during the Barcelona Air-Quality Initiative (1992), and the LDV wind data were acquired at Sunland Park, New Mexico during the 1994 Border Area Air-Quality Study. Comparisons show good agreement between the different instruments, and demonstrate the method useful for air pollution management at the local/regional scale. Elastic lidar winds could thus offer insight into aerosol and pollution transport within the PBL. Lidar wind fields might also be used to nudge or improve initialization and evaluation of atmospheric meteorological models. C1 Los Alamos Natl Lab, Div Phys, Los Alamos, NM 87545 USA. Univ Politecn Cataluna, Lab Environm Modeling, E-08028 Barcelona, Spain. RP Los Alamos Natl Lab, Div Phys, MS H803, Los Alamos, NM 87545 USA. EM buttler@lanl.gov; gnickel@lanl.gov RI Soriano, Cecilia/E-6200-2013 OI Soriano, Cecilia/0000-0002-2445-5398 NR 30 TC 9 Z9 10 U1 0 U2 3 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0006-8314 EI 1573-1472 J9 BOUND-LAY METEOROL JI Bound.-Layer Meteor. PD DEC PY 2001 VL 101 IS 3 BP 305 EP 328 DI 10.1023/A:1019274424820 PG 24 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 488ND UT WOS:000171941800001 ER PT J AU Kriebel, ME Keller, B Silver, RB Fox, GQ Pappas, GD AF Kriebel, ME Keller, B Silver, RB Fox, GQ Pappas, GD TI Porocytosis: a new approach to synaptic function SO BRAIN RESEARCH REVIEWS LA English DT Review DE transmitter secretion; quanta; porocytosis; porosome; synaptomere; synaptic vesicle ID MOUSE NEUROMUSCULAR-JUNCTION; END-PLATE POTENTIALS; MINIATURE ENDPLATE POTENTIALS; TERMINAL MEMBRANE POOLS; ATOMIC-FORCE MICROSCOPY; MOTOR-NERVE TERMINALS; TRANSMITTER RELEASE; AMPLITUDE DISTRIBUTIONS; FUSION PORE; SECRETORY VESICLE AB We propose a new approach to address the question of how a single quantum of neurotransmitter is secreted from a presynaptic terminal whose clustered secretory vesicles are locally bathed in high levels of calcium ions [Proceedings of the Symposium on Bioelectrogenesis (1961) 297-309; The Physiology of Synapses (1964) Chapters 1, 4, 5, 6; How the Self Controls its Brain (1994) Chapters 1, 4, 5, 6; Science 256 (1992) 677-679]. This hypothesis, which we term 'porocytosis', posits that the post-synaptic quantal response results from transmitter secreted through an array of docked vesicle/secretory pore complexes. The transient increase in calcium ions, which results from the voltage activated calcium channels, stimulates the array of secretory pores to simultaneously flicker open to pulse transmitter. Porocytosis is consistent with the quantal nature of presynaptic secretion and transmission, and with available biochemical, morphological and physiological evidence. It explains the frequency dependency of quantal size as a function of the secretion process. It permits a signature amount of transmitter release for different frequencies allowing a given synapse to be employed in different behavioral responses. The porocytosis hypothesis pen-nits fidelity of secretion and the seemingly apposed characteristic of synaptic plasticity. The dynamics inherent in an array insure a constant quantal size as a function of the number of units within the array. In this hypothesis, plasticity is a consequence of concurrent pre- and post-synaptic changes due to a change in array size. Changes in the number of docked vesicle-secretory pore complexes composing the array can explain facilitation, depletion, graded excitation-secretion and long term plasticity. (C) 2001 Elsevier Science B.V. All rights reserved. C1 SUNY Upstate Med Univ, Dept Neurosci & Physiol, Syracuse, NY 13210 USA. Marine Biol Lab, Woods Hole, MA 02543 USA. Argonne Natl Lab, Decis & Informat Sci Div, Argonne, IL 60439 USA. MPI Biophys Chem, D-37077 Gottingen, Germany. Univ Illinois, Coll Med, Inst Psychiat, Chicago, IL 60612 USA. RP SUNY Upstate Med Univ, Dept Neurosci & Physiol, Syracuse, NY 13210 USA. EM kriebelm@ssyr-v4.upstate.edu; bdkeller@dreamscape.com; rsilver@mbl.edu; geoffqfox@cs.com; gdpappas@uic.edu FU NINDS NIH HHS [NS S28931] NR 96 TC 6 Z9 7 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0165-0173 EI 1872-6321 J9 BRAIN RES REV JI Brain Res. Rev. PD DEC PY 2001 VL 38 IS 1-2 BP 20 EP 32 AR PII S0165-0173(01)00066-2 DI 10.1016/S0165-0173(01)00066-2 PG 13 WC Neurosciences SC Neurosciences & Neurology GA 521RJ UT WOS:000173855100002 PM 11750925 ER PT J AU Sutherling, WW Akhtari, M Mamelak, AN Mosher, J Arthur, D Sands, S Weiss, P Lopez, N DiMauro, M Flynn, E Leahy, R AF Sutherling, WW Akhtari, M Mamelak, AN Mosher, J Arthur, D Sands, S Weiss, P Lopez, N DiMauro, M Flynn, E Leahy, R TI Dipole localization of human induced focal afterdischarge seizure in simultaneous magnetoencephalography and electrocorticography SO BRAIN TOPOGRAPHY LA English DT Article DE MEG; seizure; afterdischarge; ECoG; epilepsy; dipole; frontal lobe; validation ID LANGUAGE-SPECIFIC CORTEX; INTRACRANIAL LOCALIZATIONS; MAGNETIC-FIELD; SOMATOSENSORY HOMUNCULUS; ELECTRICAL-STIMULATION; PARTIAL EPILEPSY; BRAIN; MEG; EEG; ACCURACY AB Localizations were compared for the same human seizure between simultaneously measured MEG and iEEG, which were both co-registered to MRI. The whole-cortex neuromagnetometer localized a dipole in a sphere phantom, co-registered to the MEG sensor array, with an error of 1.4 mm. A focal afterdischarge seizure was induced in a patient with partial epilepsy, by stimulation at a subdural electrocorticography (ECoG) electrode with a known location, which was co-registered to the MRI and to the MEG sensor array. The simultaneous MEG and ECoG during the 30-second seizure was measured and analyzed using the single, moving dipole model, which is the localization model used clinically. The dipole localizations from simultaneous whole cortex 68-channel MEG and 64-channel ECoG were then compared for the repetitive spiking at six different times during the seizure. There were two main regions of MEG and ECoG activity. The locations of these regions were confirmed by determining the location clusters of 8,000 dipoles on ECoG at consecutive time points during the seizure. The mean distances between the stimulated electrode location versus the dipole location of the MEG and versus the dipole location of the ECoG were each about one (1) centimeter. The mean distance between the dipole locations of the MEG versus the dipole locations of the ECoG was about 2 cm. These errors were compared to errors of MEG and ECoG reported previously for phantoms and for somatosensory evoked responses (SER) in patients. Comparing the findings from the present study to those from prior studies, there appeared to be the expected stepwise increase in mean localization error progressing from the phantom, to the SER, to the seizure. C1 Epilepsy & Brain Mapping Program, Pasadena, CA 91105 USA. Huntington Med Res Inst, Pasadena, CA USA. Huntington Hosp, Pasadena, CA USA. Univ New Mexico, Dept Phys & Astron, Albuquerque, NM 87131 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ So Calif, Signal Imaging Proc Inst, Los Angeles, CA 90089 USA. Neuroscan, El Paso, TX USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Sutherling, WW (reprint author), Epilepsy & Brain Mapping Program, 10 Congress St,Suite 505, Pasadena, CA 91105 USA. FU NCRR NIH HHS [S10 RR13276]; NIMH NIH HHS [R01 MH53213]; NINDS NIH HHS [R01 NS20806] NR 51 TC 22 Z9 22 U1 0 U2 1 PU KLUWER ACADEMIC-HUMAN SCIENCES PRESS PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013-1578 USA SN 0896-0267 J9 BRAIN TOPOGR JI Brain Topogr. PD WIN PY 2001 VL 14 IS 2 BP 101 EP 116 DI 10.1023/A:1012940812742 PG 16 WC Clinical Neurology; Neurosciences SC Neurosciences & Neurology GA 510AL UT WOS:000173186500003 PM 11797809 ER PT J AU Priestley, K Patton, HJ Schultz, CA AF Priestley, K Patton, HJ Schultz, CA TI Modeling anomalous surface-wave propagation across the Southern Caspian Basin SO BULLETIN OF THE SEISMOLOGICAL SOCIETY OF AMERICA LA English DT Article AB The South Caspian Basin contains one of the thickest sedimentary deposits in the world. Intermediate-frequency (0.02-0.04 Hz) fundamental-mode Rayleigh waves propagating across the basin are severely attenuated, but apparent attenuation is significantly less for both low and high frequencies. We have modeled the response of surface waves in a simplified rendition of the South Caspian Basin model of Mangino and Priestley (1998) using a hybrid normal-mode/2D finite-difference approach. To gain insight into the features of the basin that cause the anomalous surface-wave propagation, we have varied parameters of the basin model and computed synthetic record sections to compare with the observed seismograms. We have varied the Moho depth beneath the basin, the shape of the basin boundaries. the thickness and shear-wave Q of the sediments and mantle, and the water depth. Of these parameters, the intermediate-frequency surface waves are most severely affected by the sediment thickness and shear-wave attenuation. All models fail to satisfy observations for frequencies of 0.05 Hz and above, and this failure is attributed to significant 3D wave propagation effects caused by focusing and scattering of surface waves by basin structures. C1 Bullard Labs, Cambridge CB3 0EZ, England. Los Alamos Natl Lab, Los Alamos Seism Res Ctr, Los Alamos, NM 87545 USA. Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Priestley, K (reprint author), Bullard Labs, Madingley Rise,Madingley Rd, Cambridge CB3 0EZ, England. NR 7 TC 7 Z9 8 U1 0 U2 4 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 2001 VL 91 IS 6 BP 1924 EP 1929 DI 10.1785/0120010118 PG 6 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 520DZ UT WOS:000173766500040 ER PT J AU Tucker, AD Gibbons, JW Greene, JL AF Tucker, AD Gibbons, JW Greene, JL TI Estimates of adult survival and migration for diamondback terrapins: conservation insight from local extirpation within a metapopulation SO CANADIAN JOURNAL OF ZOOLOGY-REVUE CANADIENNE DE ZOOLOGIE LA English DT Article ID TURTLE MALACLEMYS-TERRAPIN; CAPTURE-RECAPTURE MODELS; LONG-LIVED ORGANISMS; CRAB POTS; CHELYDRA-SERPENTINA; POPULATION; SELECTION; DEMOGRAPHICS; MANAGEMENT; MORTALITY AB As a case study we analyze a recent extirpation within a metapopulation of diamondback terrapins (Malaclemys terrapin) in a South Carolina salt marsh. Survival and migration probabilities were estimated by means of a multistratum approach in Cormack-Jolly-Seber mark-recapture models to obtain transition probabilities among four tidal creeks adjoining a river. Terrapins showed high fidelity to each subpopulation and the low migration rates were insufficient for recolonizing a creek that had suffered extirpation. Annual survival rates for adult female terrapins averaged 0.84 across all creeks, ranging from 0.748 to 0.971. Survival rates were converted to instantaneous mortality rates (M) for the purpose of calculating the mean life-span as 1/M. When re-expressed in terms of mean life-span, the results confirmed that the average female terrapin did not survive to its estimated age at maturity, as might be predicted if additional mortality of females in crab pots was implicated. The results emphasize that incidental mortality of terrapins in crab pots is a conservation concern. Simple modifications of crab-pot design, such as an entrance reducer, can successfully mitigate this threat to the survival of terrapin populations. C1 Colorado State Univ, Brown Treesnake Project, Dededo, GU 96929 USA. Savannah River Ecol Lab, Aiken, SC 29801 USA. RP Tucker, AD (reprint author), Colorado State Univ, Brown Treesnake Project, POB 8255,MOU-3, Dededo, GU 96929 USA. NR 44 TC 27 Z9 32 U1 1 U2 13 PU NATL RESEARCH COUNCIL CANADA PI OTTAWA PA RESEARCH JOURNALS, MONTREAL RD, OTTAWA, ONTARIO K1A 0R6, CANADA SN 0008-4301 J9 CAN J ZOOL JI Can. J. Zool.-Rev. Can. Zool. PD DEC PY 2001 VL 79 IS 12 BP 2199 EP 2209 DI 10.1139/cjz-79-12-2199 PG 11 WC Zoology SC Zoology GA 519AX UT WOS:000173702200009 ER PT J AU Finn, JM del-Castillo-Negrete, D AF Finn, JM del-Castillo-Negrete, D TI Lagrangian chaos and Eulerian chaos in shear flow dynamics SO CHAOS LA English DT Article ID LONG-TIME CORRELATIONS; FLUID-FLOWS; HAMILTONIAN-SYSTEMS; STRANGE ATTRACTORS; MEANDERING JET; ROSSBY WAVES; PASSIVE SCALARS; TRANSPORT; INSTABILITY; VORTICITY AB Shear flow dynamics described by the two-dimensional incompressible Navier-Stokes equations is studied for a one-dimensional equilibrium vorticity profile having two minima. These lead to two linear Kelvin-Helmholtz instabilities; the resulting nonlinear waves corresponding to the two minima have different phase velocities. The nonlinear behavior is studied as a function of two parameters, the Reynolds number and a parameter lambda specifying the width of the minima in the vorticity profile. For parameters such that the instabilities grow to a sufficient level, there is Lagrangian chaos, leading to mixing of vorticity, i.e., momentum transport, between the chains of vortices or cat's eyes. Lagrangian chaos is quantified by plotting the finite time Lyapunov exponents on a grid of initial points, and by the probability distribution of these exponents. For moderate values of lambda, there is Lagrangian chaos everywhere except near the centers of the vortices and near the boundaries, and there are competing effects of homogenization of vorticity and formation of structures associated with secondary resonances. For smaller values of lambda Lagrangian chaos occurs in the regions in the centers of the vortices, and the Eulerian behavior of the flow undergoes bifurcations leading to Eulerian chaos, as measured by the time series of several Galilean invariant quantities. A discussion of Lagrangian chaos and its relation to Eulerian chaos is given. (C) 2001 American Institute of Physics. C1 Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37830 USA. RP Finn, JM (reprint author), Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. OI del-Castillo-Negrete, Diego/0000-0001-7183-801X NR 55 TC 9 Z9 9 U1 1 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 1054-1500 J9 CHAOS JI Chaos PD DEC PY 2001 VL 11 IS 4 BP 816 EP 832 DI 10.1063/1.1418762 PG 17 WC Mathematics, Applied; Physics, Mathematical SC Mathematics; Physics GA 502AK UT WOS:000172720200008 ER PT J AU Jaber, D McCoy, GA Hart, FL AF Jaber, D McCoy, GA Hart, FL TI Follow these best practices in stem system management SO CHEMICAL ENGINEERING PROGRESS LA English DT Article C1 Alliance Save Energy, Washington, DC 20036 USA. Washington State Univ, Energy Program, Olympia, WA 98504 USA. US DOE, Washington, DC 20585 USA. RP Jaber, D (reprint author), Alliance Save Energy, 1200 18th St NW,Suite 900, Washington, DC 20036 USA. NR 8 TC 1 Z9 1 U1 0 U2 1 PU AMER INST CHEMICAL ENGINEERS PI NEW YORK PA 3 PARK AVE, NEW YORK, NY 10016-5901 USA SN 0360-7275 J9 CHEM ENG PROG JI Chem. Eng. Prog. PD DEC PY 2001 VL 97 IS 12 BP 40 EP 43 PG 4 WC Engineering, Chemical SC Engineering GA 504CC UT WOS:000172838800016 ER PT J AU Holder, GD Mokka, LP Warzinski, RP AF Holder, GD Mokka, LP Warzinski, RP TI Formation of gas hydrates from single-phase aqueous solutions SO CHEMICAL ENGINEERING SCIENCE LA English DT Article DE hydrate formation; environment; ocean sequestration; thermodynamic processes; mathematical modeling; phase equilibria ID SOLUBILITY; BEHAVIOR; WATER; CO2 AB Experiments and theory both demonstrate that crystalline hydrates can form from a single-phase system consisting of liquid water with dissolved hydrate former under appropriate conditions of temperature, pressure, and dissolved hydrate former content. At these conditions, the pressure required for hydrate formation will be equal to or greater than that required when a separate gas or liquid phase of hydrate former is present. It is possible to form hydrates from a single phase when the mole fraction of dissolved hydrate former is greater than the mole fraction which would exist in the water-rich liquid phase at the three-phase (vapor/water-rich liquid/hydrate or VLH) hydrate equilibrium pressure. However, this would represent non-equilibrium or super-saturated conditions with respect to hydrate formation. It is also possible to form hydrates from a single water-rich phase when the mole fraction of the dissolved hydrate former is less than that which would exist in the presence of a gas phase at the three-phase VLH hydrate equilibrium pressure. The pressure requirement for the formation of hydrate increases as the mole fraction of hydrate former decreases under these conditions. The possibility of forming hydrates from dissolved hydrate formers may have application to potential commercial processes; for example, in the sequestration of CO2 in the deep ocean and in the recovery of hydrates from suboceanic and permafrost regions. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 US DOE, Natl Energy Technol Lab, Pittsburgh, PA 15236 USA. Univ Pittsburgh, Dept Chem & Petr Engn, Pittsburgh, PA 15261 USA. RP Warzinski, RP (reprint author), US DOE, Natl Energy Technol Lab, POB 10940, Pittsburgh, PA 15236 USA. OI Holder, Gerald/0000-0001-8890-794X NR 16 TC 10 Z9 12 U1 2 U2 9 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0009-2509 J9 CHEM ENG SCI JI Chem. Eng. Sci. PD DEC PY 2001 VL 56 IS 24 BP 6897 EP 6903 DI 10.1016/S0009-2509(01)00326-8 PG 7 WC Engineering, Chemical SC Engineering GA 503TD UT WOS:000172815800010 ER PT J AU Burleigh, MC Markowitz, MA Wong, EM Lin, JS Gaber, BP AF Burleigh, MC Markowitz, MA Wong, EM Lin, JS Gaber, BP TI Synthesis of periodic mesoporous organosilicas with block copolymer templates SO CHEMISTRY OF MATERIALS LA English DT Article ID ORGANIC GROUPS; CHANNEL WALLS; FRAMEWORKS; SILICA AB Large pore periodic mesoporous organosilicas have been synthesized using a triblock copolymer template. Organosilicas with pore sizes ranging from 6-20 mn have been prepared under acidic conditions. C1 USN, Res Lab, Lab Mol Interfacial Interact, Ctr Biomol Sci & Engn, Washington, DC 20375 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Markowitz, MA (reprint author), USN, Res Lab, Lab Mol Interfacial Interact, Ctr Biomol Sci & Engn, Code 6930, Washington, DC 20375 USA. NR 9 TC 103 Z9 103 U1 1 U2 15 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 2001 VL 13 IS 12 BP 4411 EP + DI 10.1021/cm010852d PG 3 WC Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 505AT UT WOS:000172889300006 ER PT J AU Nyman, M Bonhomme, F Maxwell, RS Nenoff, TM AF Nyman, M Bonhomme, F Maxwell, RS Nenoff, TM TI First Rb silicotitanate phase and its K-structural analogue: New members of the SNL-A family (Cc-A(2)TiSi(6)O(15); A = K, Rb, Cs) SO CHEMISTRY OF MATERIALS LA English DT Article ID POWDER DIFFRACTION DATA; SI-29 MAS NMR; TITANIUM-SILICATE; TITANOSILICATES; CS2TISI6O15; INITIO; ETS-10 AB Alkali silicotitanate ternary phases have been studied for a wide variety of applications including catalysis, selective ion exchange, and ceramic nuclear waste form materials. We report here the synthesis and structural characterization of Rb2TiSi6O15 and K2TiSi6O15, structural analogues to SNL-A (Cc-Cs2TiSi6O15). The Rb analogue is the first reported ternary oxide, the rubidium silicotitanate phase. Both the Rb and the K analogues were synthesized nearly pure by hydrothermal treatment of oxide precursor mixtures seeded with SNL-A and could not be synthesized without the addition of the seed. Rietveld refinement gave good structural models in the Cc space group with unit cell parameters: Rb2TiSi6O15, V = 1357.9 Angstrom (3), a = 12.736(2) Angstrom, b = 7.3392(3) Angstrom, c = 15.061(3) Angstrom, beta = 105.29(2)degrees and K2TiSi6O15, V = 1318. 5 Angstrom (3), a = 12.570(2) Angstrom, b = 7.2534(3) Angstrom, c = 15.082(3) Angstrom, beta = 106.49(3)degrees. The two isostructural phases were also characterized by thermogravimetry and Si-29 NMR. Unit cell parameters, melting temperatures, and Si-29 chemical shifts were compared to those of the Cs analogue and related to variation in alkali radius (Cs > Rb > K). The volume, the a-axis, and the b-axis increase linearly with alkali radius, which is directly related to a "relaxation" of the folds of the corrugated silicate layers that lie in the xy plane. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Lawrence Livermore Natl Lab, Analyt & Nucl Sci Div, Livermore, CA 94551 USA. RP Nenoff, TM (reprint author), Sandia Natl Labs, POB 8500,Dept 6233, Albuquerque, NM 87185 USA. NR 35 TC 23 Z9 23 U1 2 U2 5 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 2001 VL 13 IS 12 BP 4603 EP 4611 DI 10.1021/cm0102943 PG 9 WC Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 505AT UT WOS:000172889300032 ER PT J AU Zhang, JB Huo, L Zhang, WN Li, XH Xu, N Liu, YM AF Zhang, JB Huo, L Zhang, WN Li, XH Xu, N Liu, YM TI HBT parameters and space-momentum correlations in relativistic heavy-ion collisions SO CHINESE PHYSICS LETTERS LA English DT Article ID COLLECTIVE FLOW AB Using the relativistic quantum molecular dynamics approach, with a correlation after-burner, the physics of the transverse momentum dependence of the Hanbury-Brown and Twiss parameters is studied for Au + Au, Si + Si and p + p collisions at the centre-of-mass energy roots- = 200 AGeV. The results indicate that the space-momentum correlations would affect such dependence in both heavy-ion and elementary collisions. The size parameters as a function of the transverse mass mt are sensitive to the degree of space-momentum correlations. C1 Harbin Inst Technol, Dept Phys, Harbin 150001, Peoples R China. Natl Lab Heavy Ion Accelerator, Ctr Theoret Nucl Phys, Lanzhou 730000, Peoples R China. Lawrence Berkeley Natl Lab, Div Nucl Sci, Berkeley, CA 94720 USA. RP Zhang, JB (reprint author), Harbin Inst Technol, Dept Phys, Harbin 150001, Peoples R China. NR 17 TC 3 Z9 3 U1 0 U2 0 PU CHINESE PHYSICAL SOC PI BEIJING PA P O BOX 603, BEIJING 100080, PEOPLES R CHINA SN 0256-307X J9 CHINESE PHYS LETT JI Chin. Phys. Lett. PD DEC PY 2001 VL 18 IS 12 BP 1568 EP 1570 DI 10.1088/0256-307X/18/12/308 PG 3 WC Physics, Multidisciplinary SC Physics GA 502JW UT WOS:000172741300008 ER PT J AU Rosso, KM Rustad, JR Bylaska, EJ AF Rosso, KM Rustad, JR Bylaska, EJ TI The Cs/K exchange in muscovite interlayers: An ab initio treatment SO CLAYS AND CLAY MINERALS LA English DT Article DE ab initio; cation exchange; cesium; clay; defects; density functional theory; exchange energy; isomorphic substitution; mica; muscovite ID TOTAL-ENERGY CALCULATIONS; MOLECULAR-DYNAMICS; COMPUTER-SIMULATION; 2/1 PHYLLOSILICATES; CRYSTAL-STRUCTURE; CESIUM SORPTION; LAYER CHARGE; MONTE-CARLO; BASIS-SET; WATER AB Plane-wave pseudopotential total energy calculations have been applied to investigate the structure and energetics of the Cs/K exchange into interlayer sites in muscovite mica. Novel muscovite structures were designed to isolate the effects of 2:1 layer charge, cation size/interlayer site shape, and tetrahedral Al/Si substitutions on the exchange. All atom and cell-parameter optimizations were performed with the intention to mimic the constant pressure, non-isovolumetric exchange conditions thought to be found at frayed-edge sites. Under conditions where the cell parameters are allowed to relax, the overall Cs/K exchange reaction is surprisingly close to isoenergetic. The forward reaction is more strongly favored with increasing layer charge. For the condition of zero layer charge and no interlayer site distortion, the difference in the optimal interlayer spacing for Cs relative to K is very small, indicating a baseline indifference of the muscovite structure to cation size. The presence of 2:1 layer charge or tetrahedral rotations arising from Al/Si substitutions clearly change this outcome. Analysis of the dependence of the interlayer spacing on layer charge shows that while the spacing collapses with increasing layer charge for K as the interlayer cation, the reverse is true for Cs. We attribute the contrasting behavior to inherent differences in the ability of these cations to screen 2:1 layer-layer repulsions. Such effects might be involved during exchange at frayed-edge sites where interlayer spacings are increased. This is known, from experiment, to be very selective for Cs. Overall, the exchange energetics are so low that the Cs/K exchange rate and degree of irreversibility are likely to be dominated by diffusion kinetics. C1 Pacific NW Natl Lab, WR Wiley Environm Mol Sci Lab, Richland, WA 99352 USA. RP Rosso, KM (reprint author), Pacific NW Natl Lab, WR Wiley Environm Mol Sci Lab, Richland, WA 99352 USA. NR 55 TC 13 Z9 13 U1 2 U2 24 PU CLAY MINERALS SOCIETY PI AURORA PA PO BOX 460130, AURORA, CO 80046-0130 USA SN 0009-8604 J9 CLAY CLAY MINER JI Clay Clay Min. PD DEC PY 2001 VL 49 IS 6 BP 500 EP 513 DI 10.1346/CCMN.2001.0490603 PG 14 WC Chemistry, Physical; Geosciences, Multidisciplinary; Mineralogy; Soil Science SC Chemistry; Geology; Mineralogy; Agriculture GA 510EV UT WOS:000173196500003 ER PT J AU Latif, M Sperber, K Arblaster, J Braconnot, P Chen, D Colman, A Cubasch, U Cooper, C Delecluse, P DeWitt, D Fairhead, L Flato, G Hogan, T Ji, M Kimoto, M Kitoh, A Knutson, T Le Treut, H Li, T Manabe, S Marti, O Mechoso, C Meehl, G Power, S Roeckner, E Sirven, J Terray, L Vintzileos, A Voss, R Wang, B Washington, W Yoshikawa, I Yu, J Zebiak, S AF Latif, M Sperber, K Arblaster, J Braconnot, P Chen, D Colman, A Cubasch, U Cooper, C Delecluse, P DeWitt, D Fairhead, L Flato, G Hogan, T Ji, M Kimoto, M Kitoh, A Knutson, T Le Treut, H Li, T Manabe, S Marti, O Mechoso, C Meehl, G Power, S Roeckner, E Sirven, J Terray, L Vintzileos, A Voss, R Wang, B Washington, W Yoshikawa, I Yu, J Zebiak, S TI ENSIP: the El Nino simulation intercomparison project SO CLIMATE DYNAMICS LA English DT Article ID GENERAL-CIRCULATION MODEL; OCEAN-ATMOSPHERE MODEL; COUPLED GCM ECHO-2; TROPICAL PACIFIC; SEASONAL CYCLE; INTERANNUAL VARIABILITY; SOUTHERN OSCILLATION; PART II; INTERDECADAL VARIABILITY; EQUATORIAL OCEAN AB An ensemble of twenty four coupled ocean-atmosphere models has been compared with respect to their performance in the tropical Pacific. The coupled models span a large portion of the parameter space and differ in many respects. The intercomparison includes TOGA (Tropical Ocean Global Atmosphere)-type models consisting of high-resolution tropical ocean models and coarse-resolution global atmosphere models, coarse-resolution global coupled models, and a few global coupled models with high resolution in the equatorial region in their ocean components. The performance of the annual mean state, the seasonal cycle and the interannual variability are investigated. The primary quantity analysed is sea surface temperature (SST). Additionally, the evolution of interannual heat content variations in the tropical Pacific and the relationship between the interannual SST variations in the equatorial Pacific to fluctuations in the strength of the Indian summer monsoon are investigated. The results can be summarised as follows: almost all models (even those employing flux corrections) still have problems in simulating the SST climatology, although some improvements are found relative to earlier intercomparison studies. Only a few of the coupled models simulate the El Nino/Southern Oscillation (ENSO) in terms of gross equatorial SST anomalies realistically. In particular, many models overestimate the variability in the western equatorial Pacific and underestimate the SST variability in the east. The evolution of interannual heat content variations is similar to that observed in almost all models. Finally, the majority of the models show a strong connection between ENSO and the strength of the Indian summer monsoon. C1 Max Planck Inst Meteorol, Hamburg, Germany. LLNL, Program Climate Model Diag & Intercomparison, Livermore, CA USA. Natl Ctr Atmospher Res, Boulder, CO USA. Lab Modelisat Climat Environm, Saclay, France. Lamont Doherty Earth Observ, Palisades, NY USA. UK Meteorol Off, Bracknell, Berks, England. Deutsch Kilmarechenzentrum, Hamburg, Germany. IPSL, LODYC, Paris, France. Ctr Ocean Land Atmospher Studies, Calverton, MD USA. Meteorol Dynam Lab, Paris, France. Canadian Ctr Climate Modelling & Anal, Victoria, BC, Canada. USN, Res Lab, Monterey, CA USA. Natl Ctr Environm Predict, Camp Springs, MD USA. Ctr Climate Syst Res, Tokyo, Japan. Meteorol Res Inst, Tsukuba, Ibaraki 305, Japan. Geophys Fluid Dynam Lab, Princeton, NJ USA. Earth Frontier Res Syst, Tokyo, Japan. Univ Calif Los Angeles, Los Angeles, CA USA. Bur Meteorol Res Ctr, Melbourne, Vic, Australia. CERFACS, Toulouse, France. Univ Hawaii, Honolulu, HI 96822 USA. Japan Meteorol Agcy, Tokyo, Japan. Lamont Doherty Earth Observ, Palisades, NY USA. RP Latif, M (reprint author), Max Planck Inst Meteorol, Bundesstr 55, Hamburg, Germany. RI Marti, Olivier/B-2378-2009; Yu, Jin-Yi/G-3413-2011; kimoto, masahide/P-9077-2014; Sperber, Kenneth/H-2333-2012; Flato, Gregory/K-6711-2015; Arblaster, Julie/C-1342-2010; Latif, Mojib/C-2428-2016; Chen, Dake/E-7082-2011; Terray, Laurent/B-8056-2008 OI Yu, Jin-Yi/0000-0001-6156-7623; Arblaster, Julie/0000-0002-4287-2363; Latif, Mojib/0000-0003-1079-5604; Terray, Laurent/0000-0001-5512-7074 NR 69 TC 188 Z9 205 U1 2 U2 22 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0930-7575 J9 CLIM DYNAM JI Clim. Dyn. PD DEC PY 2001 VL 18 IS 3-4 BP 255 EP 276 DI 10.1007/s003820100174 PG 22 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 508QE UT WOS:000173099400007 ER PT J AU Bugmann, HKM Wullschleger, SD Price, DT Ogle, K Clark, DF Solomon, AM AF Bugmann, HKM Wullschleger, SD Price, DT Ogle, K Clark, DF Solomon, AM TI Comparing the performance of forest gap models in North America SO CLIMATIC CHANGE LA English DT Article ID CANADIAN BOREAL FOREST; CO2-INDUCED CLIMATE CHANGE; SPRUCE BUDWORM OUTBREAKS; FIELD-MEASUREMENTS; DYNAMICS; QUEBEC; FIRE; SUCCESSION; GRADIENTS; TRANSECT AB Forest gap models have a long history in the study of forest dynamics, including predicting long-term succession patterns and assessing the potential impacts of climate change and air pollution on forest structure and composition. In most applications, existing models are adapted for the specific question at hand and little effort is devoted to evaluating alternative formulations for key processes, although this has the potential to significantly influence model behavior. In the present study, we explore the implications of alternative formulations for selected ecological processes via the comparison of several gap models. Baseline predictions of forest biomass, composition and size structure generated by several gap models are compared to each other and to measured data at boreal and temperate sites in North America. The models ForClim and LINKAGES v2.0 were compared based on simulations of a temperate forest site in Tennessee, whereas FORSKA-2V, BOREALIS and ForClim were compared at four boreal forest sites in central and eastern Canada. Results for present-day conditions were evaluated on their success in predicting forest cover, species composition, total biomass and stand density, and allocation of biomass among species. In addition, the sensitivity of each model to climatic changes was investigated using a suite of six climate change scenarios involving temperature and precipitation. In the temperate forest simulations, both ForClim and LINKAGES v2.0 predicted mixed mesophytic forests dominated by oak species, which is expected for this region of Tennessee. The models differed in their predictions of species composition as well as with respect to the simulated rates of succession. Simulated forest dynamics under the changed climates were qualitatively similar between the two models, although aboveground biomass and species composition in ForClim was more sensitive to drought than in LINKAGES v2.0. Under a warmer climate, the modeled effects of temperature on tree growth in LINKAGES v2.0 led to the unrealistic loss of several key species. In the boreal forest simulations, ForClim predicted significant forest growth at only the most mesic site, and failed to predict a realistic species composition. In contrast, FORSKA-2V and BOREALIS were successful in simulating forest cover, general species composition, and biomass at most sites. In the climate change scenarios, ForClim was highly sensitive, whereas the other two models exhibited sensitivity only at the drier central Canadian sites. Although the studied sites differ strongly with respect to both the climatic regime and the set of dominating species, a unifying feature emerged from these simulation exercises. The major differences in model behavior were brought about by differences in the internal representations of the seasonal water balance, and they point to an important limitation in some gap model formulations for assessing climate change impacts. C1 Swiss Fed Inst Technol, ETH Zentrum, Dept Forest Sci, CH-8092 Zurich, Switzerland. Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. Nat Resources Canada, Canadian Forestry Serv, Edmonton, AB T6H 3S5, Canada. Duke Univ, Dept Bot, Durham, NC 27708 USA. Univ Virginia, Dept Environm Sci, Charlottesville, VA 22904 USA. US EPA, Western Ecol Div, Corvallis, OR 97333 USA. RP Bugmann, HKM (reprint author), Swiss Fed Inst Technol, ETH Zentrum, Dept Forest Sci, CH-8092 Zurich, Switzerland. RI Bugmann, Harald/A-1252-2008; Wullschleger, Stan/B-8297-2012; OI Wullschleger, Stan/0000-0002-9869-0446; Bugmann, Harald/0000-0003-4233-0094 NR 73 TC 34 Z9 38 U1 1 U2 15 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0165-0009 J9 CLIMATIC CHANGE JI Clim. Change PD DEC PY 2001 VL 51 IS 3-4 BP 349 EP 388 DI 10.1023/A:1012537914881 PG 40 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA 488NU UT WOS:000171943200005 ER PT J AU Norby, RJ Ogle, K Curtis, PS Badeck, FW Huth, A Hurtt, GC Kohyama, T Penuelas, J AF Norby, RJ Ogle, K Curtis, PS Badeck, FW Huth, A Hurtt, GC Kohyama, T Penuelas, J TI Aboveground growth and competition in forest gap models: An analysis for studies of climatic change SO CLIMATIC CHANGE LA English DT Review ID TROPICAL RAIN-FOREST; ELEVATED CO2; NITROGEN DEPOSITION; GLOBAL CHANGE; CARBON-DIOXIDE; DECIDUOUS FOREST; ATMOSPHERIC CO2; PINUS-TAEDA; ECOSYSTEM RESPONSE; FIELD-MEASUREMENTS AB Gap models have been used extensively in ecological studies of forest structure and succession, and they should be useful tools for studying potential responses of forests to climatic change. There is a wide variety of gap models with different degrees of physiological detail, and the manner in which the effects of climatic factors are analyzed varies across that range of detail. Here we consider how well the current suite of gap models can accommodate climatic-change issues, and we suggest what physiological attributes and responses should be added to better represent responses of aboveground growth and competition. Whether a gap model is based on highly empirical, aggregated growth functions or more mechanistic expressions of carbon uptake and allocation, the greatest challenge will be to express allocation correctly. For example, incorporating effects of elevated CO2 requires that the fixed allometry between stem volume and leaf area be made flexible. Simulation of the effects of climatic warming should incorporate the possibility of a longer growing season and acclimation of growth processes to changing temperature. To accommodate climatic-change factors, some of the simplicity of gap models must be sacrificed by increasing the amount of physiological detail, but it is important that the capability of the models to predict competition and successional dynamics not be sacrificed. C1 Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. Duke Univ, Dept Bot, Durham, NC 27706 USA. Ohio State Univ, Dept Ecol Evolut & Organismal Biol, Columbus, OH 43210 USA. Potsdam Inst Climate Impact Res, Potsdam, Germany. Univ Kassel, Ctr Environm Syst Res, D-3500 Kassel, Germany. Univ New Hampshire, Complex Syst Res Ctr, Durham, NH 03824 USA. Hokkaido Univ, Grad Sch Environm Earth Sci, Sapporo, Hokkaido 060, Japan. Univ Autonoma Barcelona, Ctr Ecol Res & Forestry Applicat, E-08193 Barcelona, Spain. RP Norby, RJ (reprint author), Oak Ridge Natl Lab, Div Environm Sci, Bldg 1059,POB 2008, Oak Ridge, TN 37831 USA. RI Badeck, Franz/C-6722-2008; Kohyama, Takashi /A-4031-2012; Hurtt, George/A-8450-2012; Norby, Richard/C-1773-2012; Penuelas, Josep/D-9704-2011 OI Badeck, Franz/0000-0001-7821-8825; Kohyama, Takashi /0000-0001-7186-8585; Norby, Richard/0000-0002-0238-9828; Penuelas, Josep/0000-0002-7215-0150 NR 144 TC 35 Z9 40 U1 3 U2 15 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0165-0009 J9 CLIMATIC CHANGE JI Clim. Change PD DEC PY 2001 VL 51 IS 3-4 BP 415 EP 447 DI 10.1023/A:1012510619424 PG 33 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA 488NU UT WOS:000171943200007 ER PT J AU Wullschleger, SD Jackson, RB Currie, WS Friend, AD Luo, Y Mouillot, F Pan, Y Shao, GF AF Wullschleger, SD Jackson, RB Currie, WS Friend, AD Luo, Y Mouillot, F Pan, Y Shao, GF TI Below-ground processes in gap models for simulating forest response to global change SO CLIMATIC CHANGE LA English DT Article ID TERRESTRIAL BIOSPHERE MODEL; CLIMATE-CHANGE; ROOTING DEPTH; NITROGEN PRODUCTIVITY; REGIONAL APPLICATIONS; LITTER DECOMPOSITION; ECOSYSTEM PROCESSES; TEMPERATE SAVANNA; SEED-GERMINATION; SOIL-MOISTURE AB Gap models have a rich history of being used to simulate individual tree interactions that impact species diversity and patterns of forest succession. Questions arise, however, as to whether these same models can be used to study the response of forest structure and composition under a changing climate. In contrast to many process-based models, gap models have traditionally been based on rather descriptive representations of species-specific growth processes. Opportunities now exist to expand upon these simple empirical relationships with more mechanistic descriptions of growth, the response of growth to environmental variables, and competition among species for available light, water, and nutrient resources. In this paper, we focus on several areas of below-ground research with the potential to improve the utility of gap models for predicting forest composition in response to a changing climate. Specific areas for model improvement include (1) improved descriptions of the soil environment for seed germination and subsequent seedling establishment, (2) multi-layer representations of soil water and nutrient availability, (3) more accurate information on biomass allocation to roots and root distribution within the soil profile, (4) improved treatment of inter- and intra-specific competition for available soil resources, (5) increased consideration of spatial processes as related to land-surface hydrology, and (6) improved attention to above- and below-ground interactions. This list is meant to stimulate discussion and provide guidance for future field research and model development. As an example of how increased attention to below-ground processes could help address intra-specific competition for water among trees of differing size classes, the gap model LINKAGES was modified to include a sub-model of multi-layered soil hydrology. It was then used to examine the impact of root distribution within soils on the simulated drought response of seedlings, saplings, and mature trees. An annual simulation of soil water content for a deciduous forest in eastern Tennessee showed that seedlings whose roots were restricted to the upper 20-cm of the soil experienced far more 'drought days' than did saplings and larger trees that otherwise had access to deeper soil water reserves. We recognize that models of forest succession cannot include mechanistic detail on all potential below-ground processes and that there are obvious tradeoffs between model simplicity and more sophisticated parameterizations. We conclude, however, that feedbacks among global environmental change, seed germination and seedling establishment, above- and below-ground carbon allocation, root distribution within the soil profile, and soil water and nutrient dynamics will be critically important for predicting forest dynamics and ecosystem function in the 21st century. As a result, steps should now be taken to ensure that these processes are represented in future gap models. C1 Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. Duke Univ, Dept Bot, Durham, NC 27708 USA. Duke Univ, Nicholas Sch Environm, Durham, NC 27708 USA. Appalachian Lab, Frostburg, MD 21532 USA. Rutgers State Univ, Ctr Environm Predict, New Brunswick, NJ 08901 USA. NASA, Goddard Inst Space Studies, New York, NY 10025 USA. Univ Oklahoma, Dept Bot & Microbiol, Norman, OK 73019 USA. CNRS, CEFE, Dynam React Ecosyst Anal Spatiale & Modelisat Uni, F-34293 Montpellier 5, France. Univ Corse, F-20250 Corte, France. US Forest Serv, USDA, Newtown Sq, PA 19073 USA. Purdue Univ, Dept Forestry & Nat Resources, W Lafayette, IN 47907 USA. RP Wullschleger, SD (reprint author), Oak Ridge Natl Lab, Div Environm Sci, POB 2008, Oak Ridge, TN 37831 USA. RI Wullschleger, Stan/B-8297-2012; MOUILLOT, florent/C-2204-2015; Pan, Yude/F-6145-2015 OI Wullschleger, Stan/0000-0002-9869-0446; MOUILLOT, florent/0000-0002-6548-4830; NR 92 TC 27 Z9 33 U1 2 U2 24 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0165-0009 J9 CLIMATIC CHANGE JI Clim. Change PD DEC PY 2001 VL 51 IS 3-4 BP 449 EP 473 DI 10.1023/A:1012570821241 PG 25 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA 488NU UT WOS:000171943200008 ER PT J AU Chen, JY Echekki, T AF Chen, JY Echekki, T TI Numerical study of buoyancy effects on the structure and propagation of triple flames SO COMBUSTION THEORY AND MODELLING LA English DT Article ID NONUNIFORM MIXTURE; NONPREMIXED JET; MIXING LAYERS; STABILIZATION; FLOWS AB The structure and propagation properties of diffusion neutral triple flames subject to buoyancy effects are studied numerically using a high-accuracy scheme. A wide range of gravity conditions, heat release, and mixing widths for a scalar mixing layer are computed for downward-propagating (in the same direction as the gravity vector) and upward-propagating (in the opposite direction to the gravity vector) triple flames. These results are used to identify non-dimensional quantities, which parametrize the triple flame responses. Results show that buoyancy acts primarily to modify the overall span of the premixed branches in response to gas acceleration across the triple flame. The impact of buoyancy on the structure of triple flame is less pronounced than its impact on the topology of the branches. The trailing diffusion branch is affected by buoyancy primarily as a result of the changes in the overall flame size, which consequently modifies the rates of diffusion of excess fuel and oxidizer from the premixed branches to the diffusion branch. A simple analytical model for the triple flame speed, which accounts for both buoyancy and heat release is developed. Comparisons of the proposed model with the numerical results for a wide range of gravity, heat release and mixing width conditions, yield very good agreement. The analysis shows that under neutral diffusion, downward propagation reduces the triple flame speed, while upward propagation enhances it. For the former condition, a critical Froude number may be evaluated, which corresponds to a vanishing triple flame speed. C1 Univ Calif Berkeley, Dept Mech Engn, Berkeley, CA 94720 USA. Sandia Natl Labs, Combust Res Facil, Livermore, CA 94550 USA. RP Echekki, T (reprint author), Univ Calif Berkeley, Dept Mech Engn, 6163 Etcheverry Hall, Berkeley, CA 94720 USA. RI Echekki, Tarek/C-7394-2009; OI Echekki, Tarek/0000-0002-0146-7994 NR 21 TC 14 Z9 15 U1 0 U2 5 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1364-7830 J9 COMBUST THEOR MODEL JI Combust. Theory Model. PD DEC PY 2001 VL 5 IS 4 BP 499 EP 515 DI 10.1088/1364-7830/5/4/301 PG 17 WC Thermodynamics; Energy & Fuels; Engineering, Chemical; Mathematics, Interdisciplinary Applications SC Thermodynamics; Energy & Fuels; Engineering; Mathematics GA 514UG UT WOS:000173459000001 ER PT J AU Hewson, JC Kerstein, AR AF Hewson, JC Kerstein, AR TI Stochastic simulation of transport and chemical kinetics in turbulent CO/H-2/N-2 flames SO COMBUSTION THEORY AND MODELLING LA English DT Article ID CONDITIONAL MOMENT CLOSURE; NONPREMIXED FLAMES; JET FLAMES; COMBUSTION; MODEL; FLOWS AB The one-dimensional turbulence (ODT) model is applied to the study of turbulent jet CO/H-2/N-2 flames. The ODT model retains the full range of length scales and no assumption of scale separation is required. In the present case, the ODT model describes the evolution of the entire flowfield; the ability of ODT to model the flowfield evolution is discussed. Predictions of the conditional means and fluctuations of temperature and the species mass fractions are compared with measurements and the level of closure required to address certain phenomena is discussed. The ODT model is shown to be useful for studying extinction/re-ignition phenomena and differential diffusion. The streamwise evolution in multidimensional flows is affected by dilatation in a manner not captured by the ODT model, and this results in discrepancies between the ODT mixing rates and the mixing rates evident in the measurements. C1 Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA. RP Hewson, JC (reprint author), Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA. NR 30 TC 38 Z9 40 U1 3 U2 6 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 1364-7830 J9 COMBUST THEOR MODEL JI Combust. Theory Model. PD DEC PY 2001 VL 5 IS 4 BP 669 EP 697 DI 10.1088/1364-7830/5/4/309 PG 29 WC Thermodynamics; Energy & Fuels; Engineering, Chemical; Mathematics, Interdisciplinary Applications SC Thermodynamics; Energy & Fuels; Engineering; Mathematics GA 514UG UT WOS:000173459000009 ER PT J AU Schoenlein, RW Chong, HHW Glover, TE Heimann, PA Leemans, WP Padmore, HA Shank, CV Zholents, AA Zolotorev, MS Corlett, JS AF Schoenlein, RW Chong, HHW Glover, TE Heimann, PA Leemans, WP Padmore, HA Shank, CV Zholents, AA Zolotorev, MS Corlett, JS TI Femtosecond X-rays from relativistic electrons: new tools for probing structural dynamics SO COMPTES RENDUS DE L ACADEMIE DES SCIENCES SERIE IV PHYSIQUE ASTROPHYSIQUE LA English DT Article DE femtosecond X-ray; synchrotron; structural dynamics; relativistic electron; Thomson scattering; slicing; beamline ID 90-DEGREES THOMSON SCATTERING; SYNCHROTRON-RADIATION; LATTICE-DYNAMICS; COMPTON-SCATTERING; BEAM INTERACTION; DIFFRACTION; LASER; GENERATION; PULSES; SPECTROSCOPY AB Femtosecond X-ray science is a new frontier in ultrafast research in which time-resolved measurement techniques are applied with X-ray pulses to investigate structural dynamics at the atomic scale on the fundamental time scale of an atomic vibrational period (similar to 100 fs). This new research area depends critically on the development of suitable femtosecond X-ray sources with the appropriate flux (ph/(s(.)0.1% BW)), brightness (ph/(s(.)mm(2.)mrad(2.)0.1% BW)), and tunability for demanding optical/X-ray pump probe experiments. In this paper we review recently demonstrated techniques for generating femtosecond X-rays via interaction between femtosecond laser pulses and relativistic electron beams. We give an overview of a novel femtosecond X-ray source that is proposed based on a linear accelerator combined with X-ray pulse compression. (C) 2001 Academie des sciences/Editions scientifiques et medicales Elsevier SAS. C1 Ernest Orlando Lawrence Berkeley Natl Lab, Div Sci Mat, Berkeley, CA USA. Univ Calif Berkeley, Appl Sci & Technol Grad Grp, Berkeley, CA 94720 USA. Lawrence Berkeley Natl Lab, Accelerator & Fus Res Div, Berkeley, CA USA. RP Schoenlein, RW (reprint author), Ernest Orlando Lawrence Berkeley Natl Lab, Div Sci Mat, Berkeley, CA USA. RI Schoenlein, Robert/D-1301-2014 OI Schoenlein, Robert/0000-0002-6066-7566 NR 56 TC 8 Z9 8 U1 0 U2 4 PU EDITIONS SCIENTIFIQUES MEDICALES ELSEVIER PI PARIS CEDEX 15 PA 23 RUE LINOIS, 75724 PARIS CEDEX 15, FRANCE SN 1296-2147 J9 CR ACAD SCI IV-PHYS JI C. R. Acad. Sci. Ser. IV-Phys. Astrophys. PD DEC PY 2001 VL 2 IS 10 BP 1373 EP 1388 DI 10.1016/S1296-2147(01)01277-X PG 16 WC Astronomy & Astrophysics; Physics, Multidisciplinary SC Astronomy & Astrophysics; Physics GA 523RJ UT WOS:000173968800002 ER PT J AU Chemla, DS AF Chemla, DS TI Correlation and coherence in semiconductors SO COMPTES RENDUS DE L ACADEMIE DES SCIENCES SERIE IV PHYSIQUE ASTROPHYSIQUE LA English DT Article DE Coulomb correlation; quantum kinetics; excitons; coherence; non-linearities; four wave mixing ID PHONON QUANTUM KINETICS; FERMI-EDGE SINGULARITY; FREE-INDUCTION DECAY; COLLECTIVE EXCITATIONS; 4-PARTICLE CORRELATIONS; COULOMB SCATTERING; HALL REGIME; BULK GAAS; WELLS; DYNAMICS AB We review recent advances, both experimental and theoretical, that have furthered our understanding of many-body effects in laser excited semiconductors and their heterostructures. They manifest themselves in two classes of phenomena. The First are observed in the coherently driven electron-hole pair system generated during and immediately after laser excitation before dissipation is turned on. The second are the effects electron-phonon and electron-electron scattering that drive the non-Markovian behavior of relaxation processes seen following laser excitation. (C) 2001 Academie des sciences/Editions scientifiques et medicales Elsevier SAS. C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. EO Lawrence Berkeley Natl Lab, Div Sci Mat, Berkeley, CA 94720 USA. RP Chemla, DS (reprint author), Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. NR 43 TC 2 Z9 2 U1 0 U2 1 PU EDITIONS SCIENTIFIQUES MEDICALES ELSEVIER PI PARIS CEDEX 15 PA 23 RUE LINOIS, 75724 PARIS CEDEX 15, FRANCE SN 1296-2147 J9 CR ACAD SCI IV-PHYS JI C. R. Acad. Sci. Ser. IV-Phys. Astrophys. PD DEC PY 2001 VL 2 IS 10 BP 1427 EP 1438 DI 10.1016/S1296-2147(01)01280-X PG 12 WC Astronomy & Astrophysics; Physics, Multidisciplinary SC Astronomy & Astrophysics; Physics GA 523RJ UT WOS:000173968800006 ER PT J AU Gwo, JP D'Azevedo, EF Frenzel, H Mayes, M Yeh, GT Jardine, PM Salvage, KM Hoffman, FM AF Gwo, JP D'Azevedo, EF Frenzel, H Mayes, M Yeh, GT Jardine, PM Salvage, KM Hoffman, FM TI HBGC123D: a high-performance computer model of coupled hydrogeological and biogeochemical processes SO COMPUTERS & GEOSCIENCES LA English DT Article DE hydrobiogeochemistry; coupled processes; bioremediation; shared-memory parallel computing; flow and transport ID REACTIVE CHEMICAL-TRANSPORT; MASS-TRANSPORT; EQUILIBRIUM CHEMISTRY; HYDROTHERMAL SYSTEMS; GROUNDWATER-FLOW; SOLUTE TRANSPORT; PERMEABLE MEDIA; NUMERICAL-MODEL; ION-EXCHANGE; POROUS-MEDIA AB Groundwater flow and transport models have been used to assist management of subsurface water resources and water quality. The needs of more efficient use of technical and financial resources have recently motivated the development of more effective remediation techniques and complex models of coupled hydrogeological and biogeochemical processes. We present a high-performance computer model of the coupled processes. HBGC123D. The model uses a hybrid Eulerian-Lagrangian finite element method to solve the solute transport equation and a Newton's method to solve the system of nonlinear, mixed kinetics and equilibrium reaction equations, Application of the model to a laboratory soil column with multispecies tracer injection suggests that one may use the model to derive important parameters of subsurface solute fate and transport. These parameters may be used for predictive purpose in similar field problems. To this end, we present a three-dimensional, hypothetical bioremediation simulation on an aquifer contaminated by CoNTA. The simulation suggests that, using oxygen alone to stimulate the biodegradation of the contaminant, one may reduce the waste to 40% in 10 years. Using a refined mesh of this three-dimensional model, we also conduct a performance study of HBGC123D on an array of SGI Origin 2000 distributed shared-memory processors. Both the computational kernels and the entire model show very good performance up to 32 processors. The CPU time is essentially reduced by 20-fold using 64 processors. This result suggests that HBGC123D may be a useful tool in assisting environmental restoration efforts such as waste site characterization and remediation. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Univ Maryland Baltimore Cty, Dept Civil & Environm Engn, Baltimore, MD 21250 USA. Oak Ridge Natl Lab, Div Math & Comp Sci, Oak Ridge, TN 37831 USA. Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. Univ Cent Florida, Dept Civil & Environm Engn, Orlando, FL 32816 USA. SUNY Binghamton, Dept Geog Sci & Environm Studies, Binghamton, NY 13902 USA. RP Gwo, JP (reprint author), Univ Maryland Baltimore Cty, Dept Civil & Environm Engn, 1000 Hilltop Circle, Baltimore, MD 21250 USA. RI Hoffman, Forrest/B-8667-2012 OI Hoffman, Forrest/0000-0001-5802-4134 NR 52 TC 22 Z9 23 U1 3 U2 8 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0098-3004 J9 COMPUT GEOSCI-UK JI Comput. Geosci. PD DEC PY 2001 VL 27 IS 10 BP 1231 EP 1242 DI 10.1016/S0098-3004(01)00027-9 PG 12 WC Computer Science, Interdisciplinary Applications; Geosciences, Multidisciplinary SC Computer Science; Geology GA 478MQ UT WOS:000171350300010 ER PT J AU Hyman, J Shashkov, M Steinberg, S AF Hyman, J Shashkov, M Steinberg, S TI The effect of inner products for discrete vector fields on the accuracy of mimetic finite difference methods SO COMPUTERS & MATHEMATICS WITH APPLICATIONS LA English DT Article DE numerical analysis; discrete vector analysis; finite difference methods; mimetic finite; difference methods; inner products; accuracy ID LOGICALLY RECTANGULAR GRIDS; NATURAL DISCRETIZATIONS; ALGORITHMS; DIVERGENCE; OPERATORS; EQUATIONS; GRADIENT; CURL AB The support operators method of discretizing partial differential equations produces discrete analogs of continuum initial boundary value problems that exactly satisfy discrete conservation laws analogous to those satisfied by the continuum system. Thus, the stability of the method is assured, but currently there is no theory that predicts the accuracy of the method on nonuniform grids. In this paper, we numerically investigate how the accuracy, particularly the accuracy of the fluxes, depends on the definition of the inner product for discrete vector fields. We introduce two different discrete inner products, the standard inner product that we have used previously and a new more accurate inner product. The definitions of these inner products are based on interpolation of the fluxes of vector fields. The derivation of the new inner product is closely related to the use of the Piola transform in mixed finite elements. Computing the formulas for the new accurate inner product requires a nontrivial use of computer algebra. From the results of our numerical experiments, we can conclude that using more accurate inner product produces a method with the same order of convergence as the standard inner product, but the constant in error estimate is about three times less. However, the method based on the standard inner product is easier to compute with and less sensitive to grid irregularities, so we recommend its use for rough grids. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Univ New Mexico, Dept Math & Stat, Albuquerque, NM 87131 USA. RP Hyman, J (reprint author), Los Alamos Natl Lab, Div Theoret, T-7,MS-B284, Los Alamos, NM 87545 USA. NR 17 TC 15 Z9 15 U1 0 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0898-1221 J9 COMPUT MATH APPL JI Comput. Math. Appl. PD DEC PY 2001 VL 42 IS 12 BP 1527 EP 1547 DI 10.1016/S0898-1221(01)00260-7 PG 21 WC Mathematics, Applied SC Mathematics GA 498YA UT WOS:000172540100003 ER PT J AU Sewards, TV Sewards, MA AF Sewards, TV Sewards, MA TI On the correlation between synchronized oscillatory activities and consciousness SO CONSCIOUSNESS AND COGNITION LA English DT Article DE consciousness; visual awareness; synchronized oscillations; retina; hippocampal formation; inferior temporal cortex; anaesthesia ID RETINAL GANGLION-CELLS; CAT VISUAL-CORTEX; BINOCULAR-RIVALRY; CORTICAL AREAS; BEHAVING RAT; INTEGRATION; RESPONSES; BINDING; SYSTEM; HIPPOCAMPUS AB Recent experiments have shown that the amplitudes of cortical gamma band oscillatory activities that occur during anesthesia are often greater than amplitudes of similar activities that occur without anesthesia. This result is apparently at odds with the hypothesis that synchronized oscillatory activities constitute the neural correlate of consciousness. We argue that while synchronization and oscillatory patterning are necessary conditions for consciousness, they are not sufficient. Based on the results of a binocular rivalry study of Fries et al. (1997), we propose that the degrees of oscillatory strength and. synchronization of neuronal activities determine the degree of awareness those activities produce. On the other hand, the overal firing rates of neurons in cortical sensory areas are not correlated with the degree of awareness the activities of those neurons produce. The results of the experiment of Fries et al. (1997) appear to conflict with the results of another binocular rivalry experiment, in which monkeys were trained to pull a lever in order to report which stimulus object was being perceived (Leopold & Logothetis, 11996). In the latter experiment, it was demonstrated that the firing rates of neurons in striate cortex did not change during perceptual alterations, while 90% of neurons in inferior and superior temporal cortices changed their firing rate when the perceived image changed. This result led to the conclusion that activities in temporal cortex are correlated with visual awareness, but those in striate cortex are not. We argue that activities in temporal cortex contribute little. if anything, to perceptual awareness, and that their primary function is computational. Thus the correlation between the firing rates of neurons in these areas and the responses of the monkeys is due to the recognition of a particular stimulus object, which: in turn is due to the computations made there. (C) 2001 Elsevier Science. C1 Sandia Res Ctr, Placitas, NM 87043 USA. RP Sewards, TV (reprint author), Sandia Res Ctr, 21 Perdiz Canyon Rd, Placitas, NM 87043 USA. NR 57 TC 12 Z9 12 U1 1 U2 3 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 1053-8100 J9 CONSCIOUS COGN JI Conscious. Cogn. PD DEC PY 2001 VL 10 IS 4 BP 485 EP 495 DI 10.1006/ccog.2001.0520 PG 11 WC Psychology, Experimental SC Psychology GA 512PE UT WOS:000173332100004 PM 11790038 ER PT J AU Arkin, AP AF Arkin, AP TI Synthetic cell biology SO CURRENT OPINION IN BIOTECHNOLOGY LA English DT Review ID ESCHERICHIA-COLI; COMBINATORIAL BIOSYNTHESIS; BACTERIAL CHEMOTAXIS; KINETIC-ANALYSIS; NETWORKS; CONSTRUCTION; PATHWAY; MODEL; BACTERIOPHAGE-T7; MECHANISMS AB Synthesis of data into formal models of cellular function is rapidly becoming a necessary industry. The complexity of the interactions among cellular constituents and the quantity of data about these interactions hinders the ability to predict how cells will respond to perturbation and how they can be engineered for industrial or medical purposes. Models provide a systematic framework to describe and analyze these complex systems. In the past few years, models have begun to have an impact on mainstream biology by creating deeper insight into the design rules of cellular signal processing, providing a basis for rational engineering of cells, and for resolving debates about the root causes of certain cellular behaviors. This review covers some of the recent work and challenges in developing these 'synthetic cell' models and their growing practical applications. C1 Univ Calif Berkeley, Howard Hughes Med Inst, Dept Bioengn, Phys Biosci Div,EO Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Arkin, AP (reprint author), Univ Calif Berkeley, Howard Hughes Med Inst, Dept Bioengn, Phys Biosci Div,EO Lawrence Berkeley Natl Lab, 1 Cyclotron Rd,MS 3-144, Berkeley, CA 94720 USA. RI Arkin, Adam/A-6751-2008 OI Arkin, Adam/0000-0002-4999-2931 NR 54 TC 64 Z9 67 U1 2 U2 14 PU CURRENT BIOLOGY LTD PI LONDON PA 84 THEOBALDS RD, LONDON WC1X 8RR, ENGLAND SN 0958-1669 J9 CURR OPIN BIOTECH JI Curr. Opin. Biotechnol. PD DEC PY 2001 VL 12 IS 6 BP 638 EP 644 DI 10.1016/S0958-1669(01)00273-7 PG 7 WC Biochemical Research Methods; Biotechnology & Applied Microbiology SC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology GA 500HD UT WOS:000172620200015 PM 11849948 ER PT J AU Lee, Y Choi, D Kende, H AF Lee, Y Choi, D Kende, H TI Expansins: ever-expanding numbers and functions SO CURRENT OPINION IN PLANT BIOLOGY LA English DT Review ID DEEP-WATER RICE; CELL-WALL EXTENSION; GROUP-I ALLERGENS; GENE-EXPRESSION; PROTEINS; GROWTH; FRUIT; PLANT; LOCALIZATION; ELONGATION AB Expansins were first identified as cell-wall-loosening proteins that, at least in part, mediate pH-dependent extension of the plant cell wall and growth of the cell. More recently, it has been realized that expansins belong to two protein families, the alpha- and beta -expansins, and that they appear to be involved in regulating, besides cell expansion, a variety of plant processes, including morphogenesis, softening of fruits, and growth of the pollen tube of grasses through the stigma and the style. The Arabidopsis genome contains 26 alpha -expansin genes and the rice genome at least 26. There are more beta -expansin genes in monocots than in dicots, at least 14 in rice and five in Arabidopsis. Expansin genes are differentially regulated by environmental and hormonal signals, and hormonal regulatory elements have been found in their promoter regions. An analysis of exon/intron structure led to the hypothesis that alpha- and beta -expansins evolved from a common ancestral gene. C1 Michigan State Univ, MSU DOE Plant Res Lab, E Lansing, MI 48824 USA. Michigan State Univ, Dept Plant Biol, E Lansing, MI 48824 USA. RP Lee, Y (reprint author), Michigan State Univ, MSU DOE Plant Res Lab, E Lansing, MI 48824 USA. NR 41 TC 154 Z9 187 U1 3 U2 28 PU CURRENT BIOLOGY LTD PI LONDON PA 84 THEOBALDS RD, LONDON WC1X 8RR, ENGLAND SN 1369-5266 J9 CURR OPIN PLANT BIOL JI Curr. Opin. Plant Biol. PD DEC PY 2001 VL 4 IS 6 BP 527 EP 532 DI 10.1016/S1369-5266(00)00211-9 PG 6 WC Plant Sciences SC Plant Sciences GA 486MZ UT WOS:000171822700009 PM 11641069 ER PT J AU Cho, HS Pelton, JG Yan, DL Kustu, S Wemmer, DE AF Cho, HS Pelton, JG Yan, DL Kustu, S Wemmer, DE TI Phosphoaspartates in bacterial signal transduction SO CURRENT OPINION IN STRUCTURAL BIOLOGY LA English DT Article ID RESPONSE REGULATOR PROTEIN; FIXJ RECEIVER DOMAIN; P-TYPE ATPASE; CRYSTAL-STRUCTURE; ESCHERICHIA-COLI; METHYLESTERASE CHEB; ANGSTROM RESOLUTION; PHOSPHORYLATION; CHEMOTAXIS; SWITCH AB Bacteria use a strategy referred to as two-component signal transduction to sense a variety of stimuli and initiate an appropriate response. Signal processing begins with proteins referred to as histidine kinases. In most cases, these are membrane-bound receptors that respond to environmental cues. Histidine kinases use ATP as a phosphodonor to phosphorylate a conserved histidine residue. Subsequent transfer of the phosphoryl group to a conserved aspartyl residue in the cognate response regulator results in an appropriate output. Recent structural studies of activated (phosphorylated) response regulators and their aspartate-bearing regulatory domains have provided insight into the links between the chemistry and biology of these ubiquitous regulatory proteins. Chemical aspects of their function appear to generalize broadly to enzymes that adopt a phosphoaspartate intermediate. C1 Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Phys Biosci Div, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Plant & Microbial Biol, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. RP Cho, HS (reprint author), Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Phys Biosci Div, 1 Cyclotron Rd, Berkeley, CA 94720 USA. FU NIGMS NIH HHS [GM62163, GM38361] NR 42 TC 39 Z9 39 U1 0 U2 0 PU CURRENT BIOLOGY LTD PI LONDON PA 84 THEOBALDS RD, LONDON WC1X 8RR, ENGLAND SN 0959-440X J9 CURR OPIN STRUC BIOL JI Curr. Opin. Struct. Biol. PD DEC PY 2001 VL 11 IS 6 BP 679 EP 684 DI 10.1016/S0959-440X(01)00271-8 PG 6 WC Biochemistry & Molecular Biology; Cell Biology SC Biochemistry & Molecular Biology; Cell Biology GA 501BV UT WOS:000172663900005 PM 11751048 ER PT J AU Salvadori, MC Fritz, MC Carraro, C Maboudian, R Monteiro, OR Brown, IG AF Salvadori, MC Fritz, MC Carraro, C Maboudian, R Monteiro, OR Brown, IG TI Characterization of AFM cantilevers coated with diamond-like carbon SO DIAMOND AND RELATED MATERIALS LA English DT Article DE resonance frequency; AFM cantilevers; elastic modulus ID CATHODIC-ARC DEPOSITION; IMMERSION ION-IMPLANTATION; PLASMA-IMMERSION; METAL PLASMA; FORCE MICROSCOPY; FILMS AB The resonance frequency of AFM cantilevers depends on the elastic modulus and on the dimensions of the cantilever. As for coated cantilevers, the resonance frequency will be determined not only by the properties of the cantilever. but also by the properties of the coating (elastic modulus and thickness). We have carried out a systematic investigation of cantilevers coated with several thicknesses of the DLC films. Measurements of the resonance frequency of the cantilevers, before and after the DLC coating, were used with a model to determine the elastic modulus of the DLC. The elastic modulus obtained for the DLC. with this model, was E(2) = 616 GPa. The AFM tip radii were also measured after coating and were found to increase with the DLC film thickness. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Sao Paulo, Inst Fis, BR-05315970 Sao Paulo, Brazil. Univ Calif Berkeley, Dept Chem Engn, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Salvadori, MC (reprint author), Univ Sao Paulo, Inst Fis, CP66318, BR-05315970 Sao Paulo, Brazil. EM mcsalvadori@if.usp.br RI Salvadori, Maria Cecilia/A-9379-2013 NR 16 TC 19 Z9 19 U1 0 U2 8 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0925-9635 J9 DIAM RELAT MATER JI Diam. Relat. Mat. PD DEC PY 2001 VL 10 IS 12 BP 2190 EP 2194 DI 10.1016/S0925-9635(01)00502-7 PG 5 WC Materials Science, Multidisciplinary SC Materials Science GA 496GX UT WOS:000172388800016 ER PT J AU Machado, G Schaeffer, R Worrell, E AF Machado, G Schaeffer, R Worrell, E TI Energy and carbon embodied in the international trade of Brazil: an input-output approach SO ECOLOGICAL ECONOMICS LA English DT Article DE embodied energy; embodied carbon; international trade; hybrid IO model; Brazil ID GREENHOUSE-GAS EMISSIONS; ECONOMIC-STRUCTURE; CONSUMPTION; POLLUTION; SERVICES; IMPORTS; GROWTH; GOODS; DAMS AB All goods and services produced in an economy are directly and/or indirectly associated with energy use and, according to the type of fuel utilized, with CO2 emissions as well. International trade is an important factor in shaping the industrial structure of a country and, consequently, in affecting a country's energy use and CO2 emissions. This study applies input-output techniques to the Brazilian economy to evaluate the total impacts of international trade on its energy use and CO2 emissions. A commodity-by-industry 10 model in hybrid units (energy commodities in physical units and non-energy commodities in monetary units) is applied to the Brazilian economy in 1995. Results show that total energy embodied in the exports of non-energy goods of Brazil equals 831 PJ, while total carbon embodied is 13.5 MtC. These amounts are larger than the relevant amounts embodied in the imports of non-energy goods, respectively 679 PJ and 9.9 MtC. These figures are better understood by contrasting them with the total energy use and the corresponding total carbon emissions of the Brazilian economy in 1995 estimated by this work: 6781 PJ and 99.4 MtC, respectively. This means that international inflows and outflows of energy embodied in non-energy goods are in the order of 10 and 12% of the total energy use, while inflows and outflows of carbon embodied in non-energy goods are approximately 10 and 14% of the corresponding total carbon emissions of the Brazilian economy in 1995. The general picture is that Brazil is not only a net exporter of energy (153 PJ) and of carbon (3.6 MtC) embodied in the non-energy goods internationally traded by the country in 1995, but also that each dollar earned with exports embodied 40% more energy and 56% more carbon than each dollar spent on imports. These findings suggest that Brazilian policy-makers should be concerned about the extra impacts international trade policy may have on energy use and carbon emissions of the country. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Fed Univ Rio De Janeiro, COPPE, Energy Planning Program, Ctr Tecnol, BR-21945970 Rio De Janeiro, Brazil. Lawrence Berkeley Lab, Environm Energy Technol Div, Berkeley, CA 94720 USA. RP Schaeffer, R (reprint author), Fed Univ Rio De Janeiro, COPPE, Energy Planning Program, Ctr Tecnol, Bloco C,Sala 211,CP 68565, BR-21945970 Rio De Janeiro, Brazil. RI Worrell, Ernst/L-5455-2013 OI Worrell, Ernst/0000-0002-0199-9755 NR 71 TC 163 Z9 197 U1 8 U2 62 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-8009 J9 ECOL ECON JI Ecol. Econ. PD DEC PY 2001 VL 39 IS 3 BP 409 EP 424 DI 10.1016/S0921-8009(01)00230-0 PG 16 WC Ecology; Economics; Environmental Sciences; Environmental Studies SC Environmental Sciences & Ecology; Business & Economics GA 504TE UT WOS:000172871300008 ER PT J AU O' Neill, RV AF O' Neill, RV TI Is it time to bury the ecosystem concept? (With full military honors of course!) SO ECOLOGY LA English DT Article DE ecosystem; ecosystem stability; ecosystem theory; ecotone; Homo sapiens; natural selection; system dynamics; Systems Analysis ID HABITAT DESTRUCTION; CATASTROPHE-THEORY; EXTINCTION DEBT; STABLE STATES; GLOBAL CHANGE; STABILITY; DISTURBANCE; POPULATION; LANDSCAPES; ECOLOGY AB The ecosystem concept has become a standard paradigm for studying ecological systems. Underlying the ecosystem concept is a "machine analogy" derived from Systems Analysis. This analogy is difficult to reconcile with our current understanding of ecological systems as metastable adaptive systems that may operate far from equilibrium. This paper discusses some logical and scientific problems associated with the ecosystem concept, and suggests a number of modifications in the paradigm to address these problems. C1 Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. RP O' Neill, RV (reprint author), Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. NR 78 TC 113 Z9 121 U1 3 U2 34 PU ECOLOGICAL SOC AMER PI WASHINGTON PA 1707 H ST NW, STE 400, WASHINGTON, DC 20006-3915 USA SN 0012-9658 J9 ECOLOGY JI Ecology PD DEC PY 2001 VL 82 IS 12 BP 3275 EP 3284 PG 10 WC Ecology SC Environmental Sciences & Ecology GA 503GY UT WOS:000172791800001 ER PT J AU Brankovic, SR Wang, JX Adzic, RR AF Brankovic, SR Wang, JX Adzic, RR TI Pt submonolayers on Ru nanoparticles - A novel low Pt loading, high CO tolerance fuel cell electrocatalyst SO ELECTROCHEMICAL AND SOLID STATE LETTERS LA English DT Article ID PLATINUM-ELECTRODES; CARBON-MONOXIDE; RUTHENIUM; OXIDATION; ADSORPTION; SURFACE; ELECTROOXIDATION; ENHANCEMENT; CLUSTERS AB A new method for the preparation of Pt-Ru and similar bimetallic electrocatalysts is reported. It involves a spontaneous deposition of Pt submonolayers on metallic Ru nanoparticles, which yields electrocatalysts with a considerably lower Pt loading and higher CO tolerance than the commercial Pt-Ru alloy electrocatalysts. The method offers a unique possibility to place the Pt atoms onto the surface of Ru nanoparticles, which very likely makes almost all of them available for hydrogen oxidation, in contrast to the Pt-Ru alloy catalysts that have Pt throughout the nanoparticles. Thus, an ultimate reduction of Pt loading can be achieved. It also facilitates a fine-tuning of the electrocatalyst's activity and selectivity by changing the coverage (the cluster size) of Pt for optimal performance under required CO tolerance levels. (C) 2001 The Electrochemical Society. [DOI: 10.1149/1.1414943] All rights reserved. C1 Brookhaven Natl Lab, Div Mat & Chem Sci, Energy Sci & Technol Dept, Upton, NY 11973 USA. RP Brankovic, SR (reprint author), Brookhaven Natl Lab, Div Mat & Chem Sci, Energy Sci & Technol Dept, Upton, NY 11973 USA. RI Wang, Jia/B-6346-2011 NR 23 TC 143 Z9 146 U1 3 U2 58 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 2001 VL 4 IS 12 BP A217 EP A220 DI 10.1149/1.1414943 PG 4 WC Electrochemistry; Materials Science, Multidisciplinary SC Electrochemistry; Materials Science GA 490BT UT WOS:000172030900008 ER PT J AU Weisshaar, DE Porter, MD AF Weisshaar, DE Porter, MD TI Site-specific voltage control of adsorption on glassy carbon electrodes SO ELECTROCHEMISTRY COMMUNICATIONS LA English DT Article DE adsorption; glassy carbon; applied potential; electrolyte; electrochemically modulated liquid chromatography ID MODULATED LIQUID-CHROMATOGRAPHY; SCANNING-TUNNELING-MICROSCOPY; RAMAN-SPECTROSCOPY; ORDERED GRAPHITE; SURFACES AB The influence of applied potential on the adsorption of organic compounds on glassy carbon (GC) electrodes has been examined using electrochemically modulated liquid chromatography (EMLC). The results not only confirm that the extent of adsorption is site dependent [Anal. Chem. 69 (1997) 4680], but also demonstrate for the first time that these sites exhibit differences in their potential dependence of adsorption. The results additionally reveal how the extent of adsorption is affected by the supporting electrolyte. Together, these results demonstrate the power of EMLC to serve as a tool for unraveling fundamental issues regarding adsorption on carbonaceous and other electrified interfaces. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Iowa State Univ, US DOE, Ames Lab, Dept Chem,Microanalyt Instrumentat Ctr, Ames, IA 50011 USA. Augustana Coll, Dept Chem, Sioux Falls, SD 57197 USA. RP Porter, MD (reprint author), Iowa State Univ, US DOE, Ames Lab, Dept Chem,Microanalyt Instrumentat Ctr, Ames, IA 50011 USA. NR 17 TC 7 Z9 7 U1 3 U2 3 PU ELSEVIER SCIENCE INC PI NEW YORK PA 360 PARK AVE SOUTH, NEW YORK, NY 10010-1710 USA SN 1388-2481 J9 ELECTROCHEM COMMUN JI Electrochem. Commun. PD DEC PY 2001 VL 3 IS 12 BP 758 EP 761 AR PII S1388-2481(01)00262-4 DI 10.1016/S1388-2481(01)00262-4 PG 4 WC Electrochemistry SC Electrochemistry GA 571QU UT WOS:000176729000016 ER PT J AU Murtishaw, S Schipper, L AF Murtishaw, S Schipper, L TI Disaggregated analysis of US energy consumption in the 1990s: evidence of the effects of the Internet and rapid economic growth SO ENERGY POLICY LA English DT Article DE decomposition analysis; structural change; Internet ID CARBON-DIOXIDE EMISSIONS AB This paper decomposes US energy use from 1988 to 1998 and attributes the changes in energy use to three underlying factors: activity, structure, and intensity. For this study we use a bottom-up methodology, by separately decomposing delivered energy use in six sectors: travel, freight, manufacturing industries, non-manufacturing industries, residential, and services. The most commonly used indicator of energy efficiency in the total economy, the ratio of energy consumed to unit of GDP (E/GDP) created can often be misleading. The rapid decline in the E/GDP ratio in recent years has been used to support assertions that the internet and information technologies in general have enabled improvements in energy efficiencies. However, our disaggregate analysis suggests that energy intensities on average are falling more slowly than ever before while actual energy use increased faster than at any time since 1970. The decline in the E/GDP ratio in the mid- to late 1990s owes much more to structural changes in the demand for energy services than to falling energy intensities. (C) 2001 Published by Elsevier Science Ltd. C1 Int Energy Agcy, Energy Technol Policy Div, F-75739 Paris 15, France. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Schipper, L (reprint author), Int Energy Agcy, Energy Technol Policy Div, 9 Rue Federat, F-75739 Paris 15, France. NR 17 TC 17 Z9 18 U1 0 U2 0 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 2001 VL 29 IS 15 BP 1335 EP 1356 DI 10.1016/S0301-4215(01)00093-3 PG 22 WC Energy & Fuels; Environmental Sciences; Environmental Studies SC Energy & Fuels; Environmental Sciences & Ecology GA 494JF UT WOS:000172278200001 ER PT J AU Jadach, S Ward, BFL Was, Z AF Jadach, S Ward, BFL Was, Z TI Global positioning of spin GPS scheme for half-spin massive spinors SO EUROPEAN PHYSICAL JOURNAL C LA English DT Article ID MONTE-CARLO; RADIATIVE-CORRECTIONS; PAIR PRODUCTION; ANNIHILATION; LEPTON AB We present a simple. and flexible method of keeping track of the complex phases and spin quantisation axes for half-spin initial- and final-state Weyl spinors in scattering amplitudes of Standard Model high energy physics processes. Both cases of massless and massive spinors are discussed. The method is demonstrated and checked numerically for spin correlations in tau(τ) over bar production and decay. Its application is in our work of combining effects due to multiple photon emission (exponentiation) and spin, embodied in the Monte Carlo event generators for production and decay of unstable fermions such as the tau leptun, t-quark and hypothetical new heavy particles. In particular, the recurrent problem of combining, for such unstable, fermions, one author's calculation of production and another author's calculation of decay, in the presence or absence of multiple photon effects, is there given a practical solution, both for Weyl spinor methods and for the traditional Jacob-Wick helicity methods. Moreover, for massive fermions we give a simple representation of the amplitude for n(gamma) emission ideally suited for numerical evaluation. No other method is known to us which for arbitrary n has been realized numerically for unstable, massive fermions. Our paper can contribute also, to the discussion on design principles of the phenomenology work for the future accelerators such as LHC or NLC. C1 CERN, Div Theory, CH-1211 Geneva 23, Switzerland. Inst Nucl Phys, PL-31342 Krakow, Poland. Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Jadach, S (reprint author), CERN, Div Theory, CH-1211 Geneva 23, Switzerland. NR 23 TC 15 Z9 15 U1 0 U2 0 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 1434-6044 J9 EUR PHYS J C JI Eur. Phys. J. C PD DEC PY 2001 VL 22 IS 3 BP 423 EP 430 DI 10.1007/s100520100818 PG 8 WC Physics, Particles & Fields SC Physics GA 509WK UT WOS:000173172600003 ER PT J AU Laplace, S Shelkov, V AF Laplace, S Shelkov, V TI CP violation and the absence of second class currents in charmless B decays SO EUROPEAN PHYSICAL JOURNAL C LA English DT Article ID ISOSPIN ANALYSIS; ASYMMETRIES AB The absence of second class currents together with the assumption of the factorization for non-leptonic B decays provide new constraints on CP observables in the decay B --> a(0)(980)(--> etapi)pi. The kinematics of this decay does not allow for interference between the oppositely charged resonances in the Dalitz plot as in B-0 --> p(770)pi. Nonetheless, under the assumption of factorization, the B --> a(0) pi two-body time-dependent isospin analysis leads to a more robust extraction of the angle cc than in the B --> ppi isospin-pentagon analysis. The absence of second class currents might lead to enhanced direct CP violation and/or allows for a test of some assumptions made in the alpha analysis in other decays like B --> a(0)p B --> b(1)(1235)pi, B --> a(0)a(0), B --> eta(eta')pipi and B --> b(1)a(0). The effects from non-factorizable contributions on the determination of a are estimated by means of a numerical study. C1 CNRS, IN2P3, Lab Accelerateur Lineaire, F-91898 Orsay, France. Univ Paris 11, F-91898 Orsay, France. Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Laplace, S (reprint author), CNRS, IN2P3, Lab Accelerateur Lineaire, BP 34, F-91898 Orsay, France. NR 14 TC 15 Z9 15 U1 0 U2 0 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 1434-6044 J9 EUR PHYS J C JI Eur. Phys. J. C PD DEC PY 2001 VL 22 IS 3 BP 431 EP 438 DI 10.1007/s100520100810 PG 8 WC Physics, Particles & Fields SC Physics GA 509WK UT WOS:000173172600004 ER PT J AU Benayoun, M O'Connell, HB AF Benayoun, M O'Connell, HB TI Isospin symmetry breaking within the HLS Model: A full (rho, omega, phi) mixing scheme SO EUROPEAN PHYSICAL JOURNAL C LA English DT Article ID PION FORM-FACTOR; HIDDEN LOCAL SYMMETRIES; DYNAMICAL GAUGE BOSONS; VECTOR-MESON DOMINANCE; DIRECT CP VIOLATION; RADIATIVE DECAYS; VEPP-2M COLLIDER; CMD-2 DETECTOR; SU(3) BREAKING; CHARGE AB We study the way isospin symmetry violation can be generated within the Hidden Local Symmetry (HLS) Model. We show that isospin symmetry breaking effects on pseudoscalar mesons naturally induces correspondingly effects within the physics of vector mesons, through kaon loops. In this way, one recovers all features traditionally expected from p - omega mixing and one finds support for the Orsay phase modelling of the c(+)c(-) --> pi(+)pi(-) amplitude. We then examine an effective procedure which generates mixing in the whole p, omega, phi sector of the HLS Model. The corresponding model allows us to account for all two body decays of light mesons accessible to the HLS model in modulus and phase, leaving aside the p --> pipi and K* --> Kpi modes only, which raise a specific problem. Comparison with experimental data is performed and covers modulus and phase information; this represents 26 physics quantities successfully described with very good fit quality within a constrained model which accounts for SU(3) breaking, nonet symmetry breaking in the pseudoscalar sector and, now, isospin symmetry breaking. C1 CERN, Lab Europeen Rech Nucl, CH-1211 Geneva 23, Switzerland. Univ Paris 06, LPNHE, Paris, France. Univ Paris 07, IN2P3, Paris, France. Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Benayoun, M (reprint author), CERN, Lab Europeen Rech Nucl, CH-1211 Geneva 23, Switzerland. OI O'Connell, Heath/0000-0002-1895-5310 NR 66 TC 23 Z9 23 U1 0 U2 0 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 1434-6044 J9 EUR PHYS J C JI Eur. Phys. J. C PD DEC PY 2001 VL 22 IS 3 BP 503 EP 520 DI 10.1007/s100520100806 PG 18 WC Physics, Particles & Fields SC Physics GA 509WK UT WOS:000173172600010 ER PT J AU Heinemeyer, S AF Heinemeyer, S TI The Higgs boson sector of the complex MSSM in the Feynman-diagrammatic approach SO EUROPEAN PHYSICAL JOURNAL C LA English DT Article ID SUPERSYMMETRIC STANDARD MODEL; EXPLICIT CP VIOLATION; ELECTROWEAK PRECISION OBSERVABLES; QCD CORRECTIONS; 2-LOOP LEVEL; MASS; RENORMALIZATION; PHASES AB In the Minimal Supersymmetric Standard Model with complex parameters (cMSSNI) we calculate higher order corrections to the Higgs boson sector in the Feynman-diagrammatic approach using the on-shell renormalization scheme. The application of this approach to the cMSSM, being complementary to existing approaches, is analyzed in detail. Numerical examples for the leading fermionic corrections, including the leading two-loop effects, are presented. Numerical agreement within 10% with other approaches is found for small and moderate mixing in the scalar top sector. The leading fermionic corrections, supplemented by the full logarithmic one-loop and the leading two-loop contributions are implemented into the public Fortran code FeynHiggsFastC. C1 Brookhaven Natl Lab, HET, Upton, NY 11973 USA. RP Heinemeyer, S (reprint author), Brookhaven Natl Lab, HET, Upton, NY 11973 USA. NR 41 TC 90 Z9 90 U1 0 U2 0 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 1434-6044 J9 EUR PHYS J C JI Eur. Phys. J. C PD DEC PY 2001 VL 22 IS 3 BP 521 EP 534 DI 10.1007/s100520100819 PG 14 WC Physics, Particles & Fields SC Physics GA 509WK UT WOS:000173172600011 ER PT J AU Martin, I Ortiz, G Balatsky, AV Bishop, AR AF Martin, I Ortiz, G Balatsky, AV Bishop, AR TI A minimal model of striped superconductors SO EUROPHYSICS LETTERS LA English DT Article ID HUBBARD-MODEL; T-C; MAGNETISM; OXIDES AB We present a minimal model of high-temperature superconductors that simultaneously supports antiferromagnetic stripes and d-wave superconductivity. At the unrestricted mean-field level, the various phases of the cuprates, including weak and strong pseudogap phases, and two different types of superconductivity in the underdoped and the overdoped regimes, nd a natural interpretation. We argue that on the underdoped side, the superconductor is intrinsically inhomogeneous and global phase coherence is achieved through Josephson-like coupling of the superconducting stripes. On the overdoped side, the state is overall homogeneous and the superconductivity is of a classical BCS type. C1 Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Martin, I (reprint author), Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. NR 28 TC 25 Z9 25 U1 0 U2 2 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 PY 2001 VL 56 IS 6 BP 849 EP 855 DI 10.1209/epl/i2001-00597-2 PG 7 WC Physics, Multidisciplinary SC Physics GA 505RM UT WOS:000172929400013 ER PT J AU Bouquet, F Wang, Y Fisher, RA Hinks, DG Jorgensen, JD Junod, A Phillips, NE AF Bouquet, F Wang, Y Fisher, RA Hinks, DG Jorgensen, JD Junod, A Phillips, NE TI Phenomenological two-gap model for the specific heat of MgB SO EUROPHYSICS LETTERS LA English DT Article ID STRONG-COUPLING SUPERCONDUCTORS; GAPS; BORON AB We show that the specific heat of the superconductor MgB2 in zero field, for which significant non-BCS features have been reported, can be fitted, essentially within experimental error, over the entire range of temperature to T-c by a phenomenological two-gap model. The resulting gap parameters agree with previous determinations from band structure calculations, and from various spectroscopic experiments. The determination from specific heat, a bulk property, shows that the presence of two superconducting gaps in MgB2 is a volume effect. C1 Univ Geneva, Dept Phys Mat Condensee, 24 Quai E Ansermet, CH-1211 Geneva 4, Switzerland. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Univ Geneva, Dept Phys Mat Condensee, 24 Quai E Ansermet, CH-1211 Geneva 4, Switzerland. NR 26 TC 238 Z9 241 U1 3 U2 23 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 0295-5075 J9 EUROPHYS LETT JI Europhys. Lett. PD DEC PY 2001 VL 56 IS 6 BP 856 EP 862 DI 10.1209/epl/i2001-00598-7 PG 7 WC Physics, Multidisciplinary SC Physics GA 505RM UT WOS:000172929400014 ER PT J AU Schnack, J Luban, M Modler, R AF Schnack, J Luban, M Modler, R TI Quantum rotational band model for the Heisenberg molecular magnet {Mo72Fe30} SO EUROPHYSICS LETTERS LA English DT Article ID MAGNETIZATION; CLUSTERS; CRYSTAL; IONS AB We derive the low-temperature properties of the molecular magnet {Mo72Fe30}, where 30 Fe3+ paramagnetic ions occupy the sites of an icosidodecahedron and interact via isotropic nearest-neighbour antiferromagnetic Heisenberg exchange. The key idea of our model (J.S. & M.L.) is that the low-lying excitations form a sequence of rotational bands, i.e., for each such band the excitation energies depend quadratically on the total spin quantum number. For temperatures below 50 mK we predict that the magnetisation is described by a staircase with 75 equidistant steps as the magnetic field is increased up to a critical value and saturated for higher fields. For higher temperatures thermal broadening effects wash out the staircase and yield a linear ramp below the critical field, and this has been confirmed by our measurements (R.M.). We demonstrate that the lowest two rotational bands are separated by an energy gap of 0.7 meV, and this could be tested by EPR and inelastic neutron scattering measurements. We also predict the occurrence of resonances at temperatures below 0.1 K in the proton NMR spin-lattice relaxation rate associated with level crossings. As rotational bands characterize the spectra of many magnetic molecules, our method opens a new road towards a description of their low-temperature behaviour which is not otherwise accessible. C1 Univ Osnabruck, Fachbereich Phys, D-49069 Osnabruck, Germany. Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. RP Schnack, J (reprint author), Univ Osnabruck, Fachbereich Phys, D-49069 Osnabruck, Germany. RI Schnack, Jurgen/A-4079-2008 OI Schnack, Jurgen/0000-0003-0702-2723 NR 17 TC 56 Z9 56 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 0295-5075 J9 EUROPHYS LETT JI Europhys. Lett. PD DEC PY 2001 VL 56 IS 6 BP 863 EP 869 DI 10.1209/epl/i2001-00599-0 PG 7 WC Physics, Multidisciplinary SC Physics GA 505RM UT WOS:000172929400015 ER PT J AU Wahl, LM Gerrish, PJ AF Wahl, LM Gerrish, PJ TI The probability that beneficial mutations are lost in populations with periodic bottlenecks SO EVOLUTION LA English DT Article DE experimental evolution; extinction probability; fixation; mathematical model; population bottleneck; serial passage ID EXPERIMENTAL EVOLUTION; ADAPTATION AB Population bottlenecks affect the dynamics of evolution, increasing the probability that beneficial mutations will be lost. Recent protocols for the experimental study of evolution involve repeated bottlenecks-when fresh media are inoculated during serial transfer or when chemostat tubes are changed. Unlike population reductions caused by stochastic environmental factors, these bottlenecks occur at known, regular intervals and with a fixed dilution ratio. We derive the ultimate probability of extinction for a beneficial mutation in a periodically bottlenecked population, using both discrete and continuous approaches. We show that both approaches yield the same approximation for extinction probability. From this, we derive an approximate expression for an effective population size. C1 Univ Western Ontario, London, ON N6A 5B7, Canada. Los Alamos Natl Lab, Los Alamos, NM 87544 USA. RP Wahl, LM (reprint author), Univ Western Ontario, London, ON N6A 5B7, Canada. OI Gerrish, Philip/0000-0001-6393-0553 NR 14 TC 61 Z9 61 U1 1 U2 12 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 2001 VL 55 IS 12 BP 2606 EP 2610 PG 5 WC Ecology; Evolutionary Biology; Genetics & Heredity SC Environmental Sciences & Ecology; Evolutionary Biology; Genetics & Heredity GA 516AA UT WOS:000173528000020 PM 11831673 ER PT J AU Curtis, RA Newman, J Blanch, HW Prausnitz, JM AF Curtis, RA Newman, J Blanch, HW Prausnitz, JM TI McMillan-Mayer solution thermodynamics for a protein in a mixed solvent SO FLUID PHASE EQUILIBRIA LA English DT Article DE liquid-liquid equilibria; aqueous salt solutions; potential of mean force model ID PREFERENTIAL INTERACTIONS; MOLECULAR THERMODYNAMICS; AQUEOUS-SOLUTIONS; PRECIPITATION; SOLUBILITY; MODEL; CRYSTALLIZATION; FRAMEWORK; SYSTEM AB McMillan-Mayer solution theory is used to calculate the thermodynamic properties of solute/solvent systems from the set of solvent-averaged interactions between solute particles. To match experimental data, the independent variables of the McMillan-Mayer framework (temperature, the set of solvent chemical potentials, and the set of solute concentrations) need to be converted to the Gibbs framework, where the independent variables are temperature, pressure, and the set of concentrations for all components. Previous conversions have been restricted to systems with a single solvent and one or more solutes. However, in the analysis of light-scattering data, it is sometimes necessary to consider multiple solvents. Here, we present the thermodynamics of McMillan-Mayer solution theory for a single protein solute and a mixed solvent of aqueous salt; we show that protein-salt preferential-interaction parameters can be readily determined from data reduction within the McMillan-Mayer framework. We provide a sample calculation of a liquid-liquid phase separation for protein solutions, wherein we convert the phase diagram from the McMillan-Mayer framework to the Gibbs framework. For the coexistence curve of the McMillan-Mayer phase diagram, the salt molality of a hypothetical outside solution is held constant, whereas for the coexistence curve for the Gibbs phase diagram, the salt molality of the light phase is held constant. The difference between the curves is determined by the preferential-interaction parameter. The two curves are identical only in the limiting case where the preferential-interaction parameter is zero, the solvent can be considered as a pseudo-one-component solvent. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Calif Berkeley, Dept Chem Engn, Berkeley, CA 94720 USA. Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA. RP Curtis, RA (reprint author), Univ Calif Berkeley, Dept Chem Engn, Berkeley, CA 94720 USA. RI Newman, John/B-8650-2008 OI Newman, John/0000-0002-9267-4525 NR 27 TC 12 Z9 12 U1 0 U2 9 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0378-3812 J9 FLUID PHASE EQUILIBR JI Fluid Phase Equilib. PD DEC 1 PY 2001 VL 192 IS 1-2 BP 131 EP 153 DI 10.1016/S0378-3812(01)00635-5 PG 23 WC Thermodynamics; Chemistry, Physical; Engineering, Chemical SC Thermodynamics; Chemistry; Engineering GA 506CX UT WOS:000172953300010 ER PT J AU Girault, I Karu, AE Schaper, M Barcellos-Hoff, MH Hagen, T Vogel, DS Ames, BN Christen, S Shigenaga, MK AF Girault, I Karu, AE Schaper, M Barcellos-Hoff, MH Hagen, T Vogel, DS Ames, BN Christen, S Shigenaga, MK TI Immunodetection of 3-nitrotyrosine in the liver of zymosan-treated rats with a new monoclonal antibody: Comparison to analysis by HPLC SO FREE RADICAL BIOLOGY AND MEDICINE LA English DT Article DE antibody; 3-nitrotyrosine; tyrosine nitration; nonparenchymal cells; free radicals; zymosan; inflammation ID NITRIC-OXIDE PRODUCTION; ACUTE LUNG INJURY; TYROSINE NITRATION; PEROXYNITRITE FORMATION; NITROTYROSINE FORMATION; SUPEROXIDE-DISMUTASE; ENDOTHELIAL-CELLS; HYPOCHLOROUS ACID; VASCULAR FAILURE; IN-VIVO AB Zymosan-induced peritonitis is associated with an increased production of reactive nitrogen oxides that may contribute to the often-observed failure of multiple organ systems in this model of acute inflammation. Quantitative biochemical evidence is provided for a marked 13-fold increase in protein-bound 3-nitrotyrosine (NTyr), a biomarker of reactive nitrogen oxides, in liver tissue of zymosan-treated rats. In order to investigate the localization of NTyr in this affected tissue, a monoclonal antibody, designated 39B6, was raised against 3-(4-hydroxy-3-nitrophenylacetamido) propionic acid-bovine serum albumin conjugate and its performance characterized. 39B6 was judged by competition ELISA to be approximate to2 orders of magnitude more sensitive than a commercial anti-NTyr monoclonal antibody. Binding characteristics of 39B6 were similar, but not identical, to that of a commercial affinity-purified polyclonal antibody in ELISA and immunohistochemical analyses. Western blot experiments revealed high specificity of 39B6 against NTyr and increased immunoreactivity of specific proteins from liver tissue homogenates of zymosan-treated rats. Immunohistochemical analysis of liver sections indicated a marked zymosan-induced increase in immunofluorescent staining, which was particularly intense in or adjacent to nonparenchymal cells, but not in the parenchymal cells of this tissue. Quantitative analysis of fractions enriched in these cell populations corroborated the immunofluorescent data, although the relative amounts detected in response to zymosan treatment was greatly reduced compared to whole liver tissue. These results demonstrate the high specificity of the newly developed antibody and its usefulness in Western blot and immunohistochemical analysis for NTyr, confirm the presence of NTyr by complementary methods, and suggest the possible involvement of reactive nitrogen oxides in hepatic vascular dysfunction. (C) 2001 Elsevier Science Inc. C1 Childrens Hosp, Oakland Res Inst, Oakland, CA 94609 USA. Univ Calif Berkeley, Div Biochem & Mol Biol, Berkeley, CA 94720 USA. Univ Calif Berkeley, Coll Nat Resources, Immunochem Facil, Berkeley, CA 94720 USA. Univ Bern, Inst Infect Dis, Bern, Switzerland. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, Berkeley, CA 94720 USA. RP Shigenaga, MK (reprint author), Childrens Hosp, Oakland Res Inst, 5700 Martin Luther King Way, Oakland, CA 94609 USA. EM mshigenaga@chori.org RI Christen, Stephan/B-8602-2009 FU NCI NIH HHS [CA 39910]; NIEHS NIH HHS [ES 01896] NR 45 TC 20 Z9 22 U1 2 U2 3 PU ELSEVIER SCIENCE INC PI NEW YORK PA 360 PARK AVE SOUTH, NEW YORK, NY 10010-1710 USA SN 0891-5849 J9 FREE RADICAL BIO MED JI Free Radic. Biol. Med. PD DEC 1 PY 2001 VL 31 IS 11 BP 1375 EP 1387 DI 10.1016/S0891-5849(01)00712-2 PG 13 WC Biochemistry & Molecular Biology; Endocrinology & Metabolism SC Biochemistry & Molecular Biology; Endocrinology & Metabolism GA 499YB UT WOS:000172597400008 PM 11728809 ER PT J AU Bundschuh, T Yun, JI Knopp, R AF Bundschuh, T Yun, JI Knopp, R TI Determination of size, concentration and elemental composition of colloids with laser-induced breakdown detection/spectroscopy (LIBD/S) SO FRESENIUS JOURNAL OF ANALYTICAL CHEMISTRY LA English DT Article; Proceedings Paper CT Colloquium on Analytical Atomic Spectrometry CY MAR 11-15, 2001 CL FREIBERG, GERMANY ID AQUEOUS-SOLUTIONS; SPECTROSCOPY; PARTICLES; LIQUIDS; WATER; SOLUBILITY; IRON AB The application of laser-induced breakdown detection (LIBD) as a new and powerful particle-analyzing technique for the determination of solubility data by monitoring initial colloid generation, when the metal ion concentration just exceeds the solubility at a given pH value, is investigated. Laser-induced breakdown spectroscopy (LIBS) is used for selective analysis of an aqueous suspension of lanthanide oxide particles in the presence of the respective lanthanide aquo ion. The detection limit for aquo ion and oxide particle is determined. On the basis of the different detection limits, the LIBS technique is used to study the formation of hydroxide colloids in aqueous solution by varying the pH value until the solubility limit is exceeded. LIBS enables both qualitative and quantitative monitoring of particle formation without artifacts arising from other contaminants. LIBD and LIBS are described and compared. The advantages and disadvantages of the methods for the determination of solubility data are discussed. C1 Res Ctr Karlsruhe GmbH, Inst Tech Chem Water Technol & Geotechnol, D-76021 Karlsruhe, Germany. Res Ctr Karlsruhe GmbH, Inst Nucl Waste Management, D-76021 Karlsruhe, Germany. Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Glenn T Seaborg Ctr, Div Chem Sci, Berkeley, CA 94720 USA. RP Bundschuh, T (reprint author), Res Ctr Karlsruhe GmbH, Inst Tech Chem Water Technol & Geotechnol, POB 3640, D-76021 Karlsruhe, Germany. RI Yun, Jong-Il/A-8863-2012 OI Yun, Jong-Il/0000-0001-8629-2259 NR 31 TC 23 Z9 24 U1 1 U2 10 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0937-0633 J9 FRESEN J ANAL CHEM JI Fresenius J. Anal. Chem. PD DEC PY 2001 VL 371 IS 8 BP 1063 EP 1069 DI 10.1007/s002160101065 PG 7 WC Chemistry, Analytical SC Chemistry GA 510FQ UT WOS:000173198400005 PM 11798098 ER PT J AU Adler, RJ Chen, PS Santiago, DI AF Adler, RJ Chen, PS Santiago, DI TI The generalized uncertainty principle and black hole remnants SO GENERAL RELATIVITY AND GRAVITATION LA English DT Article DE black holes; uncertainty principle ID QUANTUM-GRAVITY; STRING THEORY AB In the current standard viewpoint small black holes are believed to emit black body radiation at the Hawking temperature, at least until they approach Planck size, after which their fate is open to conjecture. A cogent argument against the existence of remnants is that, since no evident quantum number prevents it, black holes should radiate completely away to photons and other ordinary stable particles and vacuum, like any unstable quantum system. Here we argue the contrary, that the generalized uncertainty principle may prevent their total evaporation in exactly the same way that the uncertainty principle prevents the hydrogen atom from total collapse: the collapse is prevented, not by symmetry, but by dynamics, as a minimum size and mass are approached. C1 Stanford Univ, WW Hansen Exptl Phys Lab, Stanford, CA 94035 USA. Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. Stanford Univ, Dept Phys, Stanford, CA 94035 USA. RP Adler, RJ (reprint author), Stanford Univ, WW Hansen Exptl Phys Lab, Stanford, CA 94035 USA. NR 22 TC 301 Z9 302 U1 0 U2 4 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0001-7701 J9 GEN RELAT GRAVIT JI Gen. Relativ. Gravit. PD DEC PY 2001 VL 33 IS 12 BP 2101 EP 2108 DI 10.1023/A:1015281430411 PG 8 WC Astronomy & Astrophysics; Physics, Multidisciplinary; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 551JR UT WOS:000175557800002 ER PT J AU Jordan, G Higgins, SR Eggleston, CM Knauss, KG Schmahl, WW AF Jordan, G Higgins, SR Eggleston, CM Knauss, KG Schmahl, WW TI Dissolution kinetics of magnesite in acidic aqueous solution, a hydrothermal atomic force microscopy (HAFM) study: Step orientation and kink dynamics SO GEOCHIMICA ET COSMOCHIMICA ACTA LA English DT Article ID CARBONATES SOLUTION INTERFACE; SURFACE SPECIATION; WATER INTERFACE; IN-SITU; CALCITE; GROWTH; MORPHOLOGY; MECHANISM; LENGTH; AFM AB The dissolution kinetics of features on the magnesite (104) surface were studied in aqueous solutions from pH 4.2 to 2 and at temperatures between 60 and 90 degreesC by hydrothermal atomic force microscopy (HAFM). At pH = 4.2, HAFM images showed magnesite step orientations that are comparable to the step orientations on calcite, Similar to calcite (104), there is anisotropy in the step velocity, but the magnitude of the anisotropy is much greater for magnesite. Furthermore, below pH = 4.2, changes in the dominant step orientation were observed. These results are discussed in terms of a nearest neighbor kink dynamic model, and the associated kink dynamics were tested with kinetic Monte Carlo (KMC) simulations. The KMC results suggest that the kink dynamic model does not account for the experimental observations and that further details such as second-nearest neighbor interactions or surface/edge diffusion cannot be excluded from the model. The dominant step orientations at low pH also point toward mechanisms stabilizing steps along periodic bond chain directions. Copyright (C) 2001 Elsevier Science Ltd. C1 Ruhr Univ Bochum, Inst Geol Mineral & Geophys, D-44780 Bochum, Germany. Univ Wyoming, Dept Geol & Geophys, Laramie, WY 82071 USA. Lawrence Livermore Natl Lab, Geosci & Environm Tech Div, Livermore, CA 94550 USA. RP Jordan, G (reprint author), Ruhr Univ Bochum, Inst Geol Mineral & Geophys, D-44780 Bochum, Germany. RI Schmahl, Wolfgang/J-7571-2012; knauss, kevin/K-2827-2012 OI Schmahl, Wolfgang/0000-0002-0165-5952; NR 29 TC 64 Z9 64 U1 2 U2 26 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 2001 VL 65 IS 23 BP 4257 EP 4266 DI 10.1016/S0016-7037(01)00729-3 PG 10 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 501DJ UT WOS:000172667300001 ER PT J AU Lentz, RCF McSween, HY Ryan, J Riciputi, LR AF Lentz, RCF McSween, HY Ryan, J Riciputi, LR TI Water in martian magmas: Clues from light lithophile elements in shergottite and nakhlite pyroxenes SO GEOCHIMICA ET COSMOCHIMICA ACTA LA English DT Article ID YOUNG VOLCANIC-ROCKS; SNC METEORITES; MELT INCLUSIONS; MARS; MANTLE; BORON; SYSTEMATICS; EARTH; CRYSTALLIZATION; PETROGENESIS AB There is abundant geomorphic evidence that Mars once had potentially significant amounts of water on its surface. Bulk martian meteorites are curiously dry, and hydrated minerals found in some of these rocks are also surprisingly low in water content. We look for evidence of pre-eruptive magmatic water by analyzing the abundances of Li, Be, and B, light lithophile elements that have proven useful in tracking water-magma interactions in terrestrial studies because of their solubility differences. We performed secondary ionization mass spectrometer (SIMS) analysis of these incompatible elements in pyroxenes of two nakhlites and two basaltic shergottites, with quite different results. In Nakhla and Lafayette, all three elements behave as incompatible elements, with increasing abundance with magma evolution from pyroxene cores to rims. In Shergotty and Zagami, Be increases, but both B and Li decrease from pyroxene cores to rims. From terrestrial studies, it is known that Be is virtually insoluble in aqueous hydrothermal fluids, whereas B and Li are quite soluble. We suggest, therefore, that the elemental decreases in the shergottite pyroxenes reflect dissolution and loss of B and Li in a hot, aqueous fluid exsolved from the magma. Consistent with our results, recent experimental work proposes that the shergottite parent magmas contained 1.8 wt% water (Dann et al., 2001). We suggest that the pyroxene cores grew at depth (>4 km) where the water would remain dissolved in the magma. Once the magma began to ascend, the volatile component could gradually exsolve, removing the soluble species from the melt in the process. Upon eruption, the volatile component might then be lost through degassing, leaving a B- and Li-depleted magma to crystallize pyroxene rims and plagioclase. This magmatic water might have derived from the martian mantle or resulted from deep crustal contamination. If the water contents proposed for the shergottite magmas, and implied by our results, are typical of basaltic magmas on Mars, this mechanism could provide an efficient method of delivering substantial amounts of water to the martian surface at later times in martian history. Copyright (C) 2001 Elsevier Science Ltd. C1 Univ Tennessee, Dept Geol Sci, Knoxville, TN 37996 USA. Univ S Florida, Dept Geol, Tampa, FL 33620 USA. Oak Ridge Natl Lab, Chem & Analyt Sci Div, Oak Ridge, TN 37831 USA. RP Univ Tennessee, Dept Geol Sci, Knoxville, TN 37996 USA. EM rlentz@utk.edu NR 56 TC 45 Z9 45 U1 0 U2 9 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0016-7037 EI 1872-9533 J9 GEOCHIM COSMOCHIM AC JI Geochim. Cosmochim. Acta PD DEC PY 2001 VL 65 IS 24 BP 4551 EP 4565 DI 10.1016/S0016-7037(01)00756-6 PG 15 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 506FF UT WOS:000172958600010 ER PT J AU Chen, ZS Riciputi, LR Mora, CI Fishman, NS AF Chen, ZS Riciputi, LR Mora, CI Fishman, NS TI Regional fluid migration in the Illinois basin: Evidence from in situ oxygen isotope analysis of authigenic K-feldspar and quartz from the Mount Simon Sandstone SO GEOLOGY LA English DT Article DE ion probe; oxygen; isotopes; authigenic minerals; Illinois basin; fluid migration ID UPPER MISSISSIPPI VALLEY; POTASSIC DIAGENESIS; ST-PETER; PALEOHYDROLOGY; FRACTIONATION; SPHALERITE; ANORTHITE; CALCITE; ALBITE; USA AB Oxygen isotope compositions of widespread, authigenic K-feldspar and quartz overgrowths and cements in the Upper Cambrian Mount Simon Sandstone were measured by ion microprobe in 11 samples distributed across the Illinois basin and its periphery. Average K-feldspar delta O-18 values increase systematically from +14 parts per thousand +/- 1 parts per thousand in the southern-most and deepest samples in Illinois to +24 parts per thousand +/- 2 parts per thousand in the northernmost outcrop sample in Wisconsin. A similar trend was observed for quartz overgrowths (22 parts per thousand +/- 2 parts per thousand to 28 parts per thousand +/- 2 parts per thousand). Constant homogenization temperatures (100-130 degreesC) of fluid inclusions associated with quartz overgrowths throughout the basin suggest that the geographic trend in oxygen isotope compositions is a result of diagenetic modification of a south to north migrating basinal fluid. C1 Univ Tennessee, Dept Geol Sci, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. US Geol Survey, Lakewood, CO 80225 USA. RP Chen, ZS (reprint author), Univ Tennessee, Dept Geol Sci, Knoxville, TN 37996 USA. RI Mora, Claudia/B-5511-2017 OI Mora, Claudia/0000-0003-2042-0208 NR 30 TC 17 Z9 18 U1 0 U2 8 PU GEOLOGICAL SOC AMERICA, INC PI BOULDER PA PO BOX 9140, BOULDER, CO 80301-9140 USA SN 0091-7613 J9 GEOLOGY JI Geology PD DEC PY 2001 VL 29 IS 12 BP 1067 EP 1070 DI 10.1130/0091-7613(2001)029<1067:RFMITI>2.0.CO;2 PG 4 WC Geology SC Geology GA 501DG UT WOS:000172667100001 ER PT J AU Winter, CL Tartakovsky, DM AF Winter, CL Tartakovsky, DM TI Theoretical foundation for conductivity scaling SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID TRUNCATED POWER VARIOGRAMS; RANDOM-FIELDS; MEDIA AB Scaling of conductivity with the support volume of experiments has been the subject of many recent experimental and theoretical studies. However, to date there have been few attempts to relate such scaling, or the lack thereof, to microscopic properties of porous media through theory. We demonstrate that when a pore network can be represented as a collection of hierarchical trees, scalability of the pore geometry leads to scalability of conductivity. We also derive geometrical and topological conditions under which the scaling exponent takes on specific values 1/2 and 3/4. The former is consistent with universal scaling observed by Neuman [1994], while the latter agrees with the allometric scaling laws derived by West et al. [1997]. C1 Los Alamos Natl Lab, Div Theoret, Grp T 7, Los Alamos, NM 87545 USA. RP Winter, CL (reprint author), Los Alamos Natl Lab, Div Theoret, Grp T 7, MS B256, Los Alamos, NM 87545 USA. RI Tartakovsky, Daniel/E-7694-2013; Winter, C. Larrabee/D-3918-2013 NR 9 TC 5 Z9 5 U1 0 U2 5 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 2001 VL 28 IS 23 BP 4367 EP 4369 DI 10.1029/2001GL013680 PG 3 WC Geosciences, Multidisciplinary SC Geology GA 496YJ UT WOS:000172425700007 ER PT J AU Johnson, JR Cheng, CZ AF Johnson, JR Cheng, CZ TI Stochastic ion heating at the magnetopause due to kinetic Alfven waves SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID RESONANT AMPLIFICATION; SUBSOLAR MAGNETOPAUSE; DAYSIDE MAGNETOPAUSE; PLASMA TRANSPORT AB The magnetopause and boundary layer are typically characterized by large amplitude transverse wave activity with frequencies below the ion cyclotron frequency. The signatures of the transverse waves suggest that they are kinetic Alfven waves with wavelength on the order of the ion gyroradius [Johnson and Cheng, 1997a; Johnson et al., 2001]. We investigate ion motion in the presence of large amplitude kinetic Alfven waves with wavelength the order of pi and demonstrate that for sufficiently large wave amplitude (deltaB(perpendicular to)/B-0 > 0.05) the particle orbits become stochastic. As a result, low energy particles in the core of the ion distribution can migrate to higher energy through the stochastic sea leading to an increase in T-perpendicular to and a broadening of the distribution. This process can explain transverse ion energization and formation of conics which have been observed near the magnetopause in both the magnetosheath and low-latitude boundary layer. C1 Princeton Univ, Plasma Phys Lab, Princeton, NJ 08543 USA. RP Johnson, JR (reprint author), Princeton Univ, Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. RI Cheng, Chio/K-1005-2014 NR 19 TC 71 Z9 71 U1 2 U2 4 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 2001 VL 28 IS 23 BP 4421 EP 4424 DI 10.1029/2001GL013509 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 496YJ UT WOS:000172425700021 ER PT J AU Turner, DD Ferrare, RA Brasseur, LA AF Turner, DD Ferrare, RA Brasseur, LA TI Average aerosol extinction and water vapor profiles over the southern great plains SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID RAMAN LIDAR; SITE AB An operational Raman lidar deployed at the DOE Atmospheric Radiation Measurement site in Oklahoma has collected more than 7500 h of aerosol and water vapor data between April 1998 and January 2000. These data, which span a wide variety of atmospheric conditions, have been analyzed as a function of season, integrated amount, and time of day. The scale height of the mean aerosol profiles varies considerably as both a function of season and aerosol optical thickness, with the mean scale height increasing from less than I km in the winter to over 2 km during turbid summer days. The mean scale height of the water vapor remained very close to 2 km, regardless of season or precipitable water vapor. Furthermore, the distribution of aerosol optical thickness shows a slight shift to smaller values at night compared to day, and the mean aerosol profiles show little diurnal dependence except at the top of the boundary layer. C1 Pacific NW Natl Lab, Climate Dynam Grp, Richland, WA 99352 USA. NASA, Langley Res Ctr, Chem & Dynam Branch, Hampton, VA 23681 USA. NASA, Langley Res Ctr, SAIC, Hampton, VA 23681 USA. RP Turner, DD (reprint author), Univ Wisconsin, 1225 W Dayton St, Madison, WI 53706 USA. NR 9 TC 39 Z9 40 U1 2 U2 8 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 2001 VL 28 IS 23 BP 4441 EP 4444 DI 10.1029/2001GL013691 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 496YJ UT WOS:000172425700026 ER PT J AU Moore, WS Liu, TZ Broecker, WS Finkel, RC Wright, A AF Moore, WS Liu, TZ Broecker, WS Finkel, RC Wright, A TI Factors influencing Be-7 accumulation on rock varnish SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID DESERT VARNISH; SONORAN DESERT; MANGANESE; DEPOSITION; BACTERIA; FUNGI; IRON AB Rocks coated with desert varnish were translocated from Scottsdale, Arizona, and Panamint Valley, California, to a fenced-in plot near Biosphere 2 where they were allowed to accumulate a new crop of the 53 day half life, cosmic ray-produced Be-7. Those exposed to precipitation accumulated several times more of this isotope than those shielded from precipitation. No significant difference in Be-7 accumulation was observed between a set which was UV irradiated (in an attempt to kill resident bacteria) and a set which received no UV irradiation. This experiment suggests that 62 +/- 10 percent of the beryllium accumulated on the varnish was supplied by precipitation and 38 10 percent by some combination of dew, dust, and aerosols. If bacteria are, as has been proposed, responsible for varnish growth, then either our UV irradiation was inadequate to squelch their activity or the Be-7 we measured had not yet been built into the varnish. C1 Univ S Carolina, Dept Geol Sci, Columbia, SC 29208 USA. Columbia Univ, Lamont Doherty Earth Observ, Palisades, NY 10964 USA. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Columbia Univ, Biosphere Ctr 2, Oracle, AZ 85623 USA. RP Moore, WS (reprint author), Univ S Carolina, Dept Geol Sci, Columbia, SC 29208 USA. RI Moore, Willard/B-6096-2016 OI Moore, Willard/0000-0001-5930-5325 NR 22 TC 9 Z9 9 U1 0 U2 6 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 2001 VL 28 IS 23 BP 4475 EP 4478 DI 10.1029/2001GL013226 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 496YJ UT WOS:000172425700035 ER PT J AU Shook, GM AF Shook, GM TI Predicting thermal breakthrough in heterogeneous media from tracer tests SO GEOTHERMICS LA English DT Article DE tracers; reservoir; thermal front AB Analysis of the conservation equations demonstrates that the ratio of fluid-to-temperature velocities is a constant, even in heterogeneous media, Because tracers move at the bulk fluid velocity, tracer test analysis can be used to predict temperature declines at production wells that result from injection. Tracer histories are transformed into predicted temperature histories through a simple variable transformation. Examples demonstrate that the method works well for single-phase flow in heterogeneous (but porous) media. In the presence of strong permeability correlation (layering), the method's accuracy degrades somewhat; the onset of cooling, however, is still predicted reasonably accurately. (C) 2001 CNR. Published by Elsevier Science Ltd. All rights reserved. C1 Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. RP Shook, GM (reprint author), Idaho Natl Engn & Environm Lab, POB 1625,MS 2107, Idaho Falls, ID 83415 USA. NR 15 TC 29 Z9 30 U1 0 U2 6 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0375-6505 J9 GEOTHERMICS JI Geothermics PD DEC PY 2001 VL 30 IS 6 BP 573 EP 589 DI 10.1016/S0375-6505(01)00015-3 PG 17 WC Energy & Fuels; Geosciences, Multidisciplinary SC Energy & Fuels; Geology GA 499HV UT WOS:000172566500001 ER PT J AU Dinnel-Jones, K AF Dinnel-Jones, K TI 2001 Founders Award - Presented to J. Newell Stannard - at the 46th Annual Meeting of the Health Physics Society, Cleveland, OH - 10-14 June 2001 SO HEALTH PHYSICS LA English DT Biographical-Item C1 Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Dinnel-Jones, K (reprint author), Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 1 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 2001 VL 81 IS 6 BP 615 EP 616 DI 10.1097/00004032-200112000-00001 PG 2 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 495QY UT WOS:000172352900001 PM 11725873 ER PT J AU Fisher, DR AF Fisher, DR TI 2001 Elda E. Anderson Award - Presented to Tsz-Yik Edmond Hui - At the 46th Annual Meeting of the Health Physics Society, Cleveland, OH - 10-14 June 2001 SO HEALTH PHYSICS LA English DT Biographical-Item C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Fisher, DR (reprint author), Pacific NW Natl Lab, 902 Battelle Blvd, Richland, WA 99352 USA. NR 1 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 2001 VL 81 IS 6 BP 620 EP 622 DI 10.1097/00004032-200112000-00003 PG 3 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 495QY UT WOS:000172352900003 PM 11725875 ER PT J AU Zhang, JB Huo, L Zhang, WN Liu, YM Li, XH Yang, J Xu, N AF Zhang, JB Huo, L Zhang, WN Liu, YM Li, XH Yang, J Xu, N TI HBT parameters for Au plus Au collisions at RHIC energy SO HIGH ENERGY PHYSICS AND NUCLEAR PHYSICS-CHINESE EDITION LA English DT Letter DE heavy-ion collisions; HBT correlation; correlation function ID HEAVY-ION COLLISIONS; INTERFEROMETRY; DEPENDENCE; FLOW AB Using the dynamical transport approach RQMD vith a correlation afterburner, the behavior of two-pion HBT parameters is studied for Au + Au collisions at RHIC energy roots = 200GeV/u. We find that the HBT size parameters do reflect the source geometry at freeze-out for both central and non-central collisions. The transverse momentum dependence of HBT size parameters is insensitive to the pressure developed during the early stage of the collisions, rather, it is sensitive to the degree of spacemomentum correlation. C1 Harbin Inst Technol, Dept Phys, Harbin 150001, Peoples R China. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. RP Zhang, JB (reprint author), Harbin Inst Technol, Dept Phys, Harbin 150001, Peoples R China. NR 15 TC 0 Z9 0 U1 0 U2 0 PU SCIENCE CHINA PRESS PI BEIJING PA 16 DONGHUANGCHENGGEN NORTH ST, BEIJING 100717, PEOPLES R CHINA SN 0254-3052 J9 HIGH ENERG PHYS NUC JI High Energy Phys. Nucl. Phys.-Chin. Ed. PD DEC PY 2001 VL 25 IS 12 BP 1253 EP 1257 PG 5 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 504GT UT WOS:000172849500019 ER PT J AU Bolton, FN Kleinsteuber, JF AF Bolton, FN Kleinsteuber, JF TI A perspective on the effectiveness of risk assessment by first-line workers and supervisors in a safety management system SO HUMAN AND ECOLOGICAL RISK ASSESSMENT LA English DT Article DE hazard analysis; behavior-based safety; failure; management; paperwork AB In 1996, the Los Alamos National Laboratory restructured its safety management system to require formal hazard analysis and risk determination for its operations and activities. This paper provides a perspective on the effectiveness of those efforts. An overview of the safety management system is provided, and some influencing factors reviewed, such as management, bureaucratic hurdles, paperwork, hazard analysis, behavioral aspects, and the role of failure. Barriers to success, potential benefits, and challenges are discussed. C1 Hazardous Mat Response Grp, Los Alamos, NM 87545 USA. Los Alamos Natl Lab, Div Nucl Mat Technol, Los Alamos, NM 87545 USA. RP Bolton, FN (reprint author), Hazardous Mat Response Grp, Mailstop K542, Los Alamos, NM 87545 USA. NR 12 TC 2 Z9 2 U1 0 U2 2 PU CRC PRESS LLC PI BOCA RATON PA 2000 CORPORATE BLVD NW, JOURNALS CUSTOMER SERVICE, BOCA RATON, FL 33431 USA SN 1080-7039 J9 HUM ECOL RISK ASSESS JI Hum. Ecol. Risk Assess. PD DEC PY 2001 VL 7 IS 7 BP 1777 EP 1786 DI 10.1080/20018091095384 PG 10 WC Biodiversity Conservation; Environmental Sciences SC Biodiversity & Conservation; Environmental Sciences & Ecology GA 513UK UT WOS:000173397700003 ER PT J AU Kress, RL Hamel, WR Murray, P Bills, K AF Kress, RL Hamel, WR Murray, P Bills, K TI Control strategies for teleoperated Internet assembly SO IEEE-ASME TRANSACTIONS ON MECHATRONICS LA English DT Article DE assembly; control; internet; teleoperations AB Teleoperated systems are increasingly being used to perform tasks across the Internet. This paper discusses this general idea in terms of the control needs, constraints and concepts that are associated with the notion of Internet-based assembly. A discrete-event simulation is used to investigate several supervisory control strategies used for the assembly of a standardized fixture (the Cranfield) using teleoperated commands issued across the Internet. Results are presented relating assembly performance. control strategy and Internet communication performance. C1 Univ Tennessee, Dept Mech & Aerosp Engn & Engn Sci, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Kress, RL (reprint author), Univ Tennessee, Dept Mech & Aerosp Engn & Engn Sci, Knoxville, TN 37996 USA. NR 20 TC 17 Z9 17 U1 0 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1083-4435 J9 IEEE-ASME T MECH JI IEEE-ASME Trans. Mechatron. PD DEC PY 2001 VL 6 IS 4 BP 410 EP 416 DI 10.1109/3516.974854 PG 7 WC Automation & Control Systems; Engineering, Manufacturing; Engineering, Electrical & Electronic; Engineering, Mechanical SC Automation & Control Systems; Engineering GA 511ZY UT WOS:000173297700006 ER PT J AU Rinaldi, SA Peerenboom, JP Kelly, TK AF Rinaldi, SA Peerenboom, JP Kelly, TK TI Identifying, understanding, and analyzing critical infrastructure interdependencies SO IEEE CONTROL SYSTEMS MAGAZINE LA English DT Article C1 USAF, Quadrennial Def Review, Washington, DC 20330 USA. Argonne Natl Lab, Argonne, IL 60439 USA. Execut Off President, Washington, DC 20502 USA. RP Rinaldi, SA (reprint author), USAF, Quadrennial Def Review, Washington, DC 20330 USA. NR 26 TC 463 Z9 480 U1 3 U2 60 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0272-1708 J9 IEEE CONTR SYST MAG JI IEEE Control Syst. Mag. PD DEC PY 2001 VL 21 IS 6 BP 11 EP 25 DI 10.1109/37.969131 PG 15 WC Automation & Control Systems SC Automation & Control Systems GA 495YT UT WOS:000172368500002 ER PT J AU Mielke, AM Boyle, CM Buenafe, CA Dreicer, JS Gattiker, JR Martinez, BJ Smith, DA AF Mielke, AM Boyle, CM Buenafe, CA Dreicer, JS Gattiker, JR Martinez, BJ Smith, DA TI Continuous monitoring of a capacitor bank SO IEEE INSTRUMENTATION & MEASUREMENT MAGAZINE LA English DT Article C1 Los Alamos Natl Lab, Safeguards Syst Grp, Los Alamos, NM 87545 USA. RP Mielke, AM (reprint author), Los Alamos Natl Lab, Safeguards Syst Grp, Los Alamos, NM 87545 USA. NR 3 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 1094-6969 J9 IEEE INSTRU MEAS MAG JI IEEE Instrum. Meas. Mag. PD DEC PY 2001 VL 4 IS 4 BP 14 EP 19 DI 10.1109/5289.975460 PG 6 WC Engineering, Electrical & Electronic; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA 508XP UT WOS:000173115300005 ER PT J AU Mirkarimi, PB Spiller, EA Stearns, DG Sperry, V Baker, SL AF Mirkarimi, PB Spiller, EA Stearns, DG Sperry, V Baker, SL TI An ion-assisted Mo-Si deposition process for planarizing reticle substrates for extreme ultraviolet lithography SO IEEE JOURNAL OF QUANTUM ELECTRONICS LA English DT Article DE ion beam applications; integrated circuit fabrication; masks; photolithography; thin films ID THIN-FILMS; MULTILAYER; DEFECTS; MO/SI AB Substrate particles are a serious concern in the fabrication of reticles for extreme ultraviolet lithography (EUVL) because they nucleate defects in the reflective multilayer films that can print in the lithographic image. We have developed a strategy for planarizing reticle substrates with smoothing-layers and, in this letter, we investigate the smoothing properties of an ion-assisted Mo-Si deposition process. We have observed that ion-assistance can significantly improve the particle-smoothing properties of Mo-Si multilayer films and can do so without a significant increase in the high-spatial frequency roughness of the multilayer film. An ion-assisted Mo-Si smoothing-layer approach to reticle substrate planarization, therefore, shows significant promise for defect mitigation in EUVL reticles. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Spiller Xray Opt, Mt Kisco, NY 10549 USA. OS Associates, Mt View, CA 94040 USA. RP Mirkarimi, PB (reprint author), Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 18 TC 25 Z9 25 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 0018-9197 J9 IEEE J QUANTUM ELECT JI IEEE J. Quantum Electron. PD DEC PY 2001 VL 37 IS 12 BP 1514 EP 1516 DI 10.1109/3.970896 PG 3 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA 502DF UT WOS:000172727900005 ER PT J AU Liu, Y Chen, HF Liu, JM Davis, P Aida, T AF Liu, Y Chen, HF Liu, JM Davis, P Aida, T TI Communication using synchronization of optical-feedback-induced chaos in semiconductor lasers SO IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS I-REGULAR PAPERS LA English DT Article DE chaos synchronization; injection locking; optical chaos; optical communication; optical feedback ID DELAYED FEEDBACK; DYNAMICS; SYSTEM AB A communication system based on the synchronization of optical chaos in semiconductor lasers is proposed. The optical chaos is generated in a single-mode semiconductor laser with external ring optical feedback. Synchronization of chaos is performed by a direct optical-injection scheme that consists of a transmitter laser with an external optical feedback and a receiver laser with optical injection from the transmitter laser. Both numerical and experimental results on synchronization of gigs-hertz chaotic signals are presented. Direct encoding of 2.5 Gbps messages on the chaotic waveform is numerically demonstrated. The bit-error rate shows a sensitive dependence on the frequency detuning. C1 ATR Adapt Commun Res Labs, Seika, Kyoto 6190288, Japan. Oak Ridge Natl Lab, Ctr Engn Sci Adv Res, Div Math & Comp Sci, Oak Ridge, TN 37831 USA. Univ Calif Los Angeles, Dept Elect Engn, Los Angeles, CA 90095 USA. RP ATR Adapt Commun Res Labs, Seika, Kyoto 6190288, Japan. EM liuy2@ornl.gov NR 22 TC 48 Z9 51 U1 2 U2 8 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 1549-8328 EI 1558-0806 J9 IEEE T CIRCUITS-I JI IEEE Trans. Circuits Syst. I-Regul. Pap. PD DEC PY 2001 VL 48 IS 12 BP 1484 EP 1490 DI 10.1109/TCSI.2001.972855 PG 7 WC Engineering, Electrical & Electronic SC Engineering GA 504FV UT WOS:000172847400011 ER PT J AU Tucker, JB Rao, MV Papanicolaou, NA Mittereder, J Elasser, A Clock, AW Ghezzo, M Holland, OW Jones, KA AF Tucker, JB Rao, MV Papanicolaou, NA Mittereder, J Elasser, A Clock, AW Ghezzo, M Holland, OW Jones, KA TI Characteristics of planar n-p junction diodes made by double-implantations into 4H-SiC SO IEEE TRANSACTIONS ON ELECTRON DEVICES LA English DT Article DE aluminum; Boron; diode; ion implantation; Nitrogen; planar; Silicon Carbide; transient ID POWER DEVICES; BORON; ALUMINUM; SILICON AB Double implantation technology consisting of deep-range acceptor followed by shallow-range donor implantation was used to fabricate planar n(+) -p junction diodes in 4H-SiC. Either Al or B was used as the acceptor species and N as the donor species with all implants performed at 700 degreesC and annealed at 1650 degreesC with an AIN encapsulant. The diodes were characterized for their current-voltage (I-V) and capacitance-voltage (C-V) behavior over the temperature range 25 degreesC-400 degreesC, and reverse recovery transient behavior over the temperature range 25 degreesC-200 degreesC. At room temperature, the B-implanted diodes exhibited a reverse leakage current of 5 X 10(-8) A/cm(2) at a reverse bias of -20 V and a carrier lifetime of 7.4 ns. C1 Gen Elect Corp Res & Dev, Niskayuna, NY 12309 USA. GE Co, Ctr Corp Res & Dev, Schenectady, NY 12301 USA. George Mason Univ, Fairfax, VA 22030 USA. USN, Res Lab, Washington, DC 20375 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. USA, Res Lab, Adelphi, MD 20783 USA. RP Tucker, JB (reprint author), Gen Elect Corp Res & Dev, Niskayuna, NY 12309 USA. NR 17 TC 5 Z9 5 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 0018-9383 J9 IEEE T ELECTRON DEV JI IEEE Trans. Electron Devices PD DEC PY 2001 VL 48 IS 12 BP 2665 EP 2670 DI 10.1109/16.974687 PG 6 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 511HZ UT WOS:000173259700002 ER PT J AU Kueck, JD Attarian, GE Leake, HC Sims, TR AF Kueck, JD Attarian, GE Leake, HC Sims, TR TI Risk factors regarding the application of degraded voltage relaying at nuclear generating stations SO IEEE TRANSACTIONS ON ENERGY CONVERSION LA English DT Article DE degraded voltage relaying; nuclear safety-related bus voltages AB Nuclear generating stations utilize degraded voltage relaying schemes to protect electrical equipment against sustained low voltage conditions. Based on regulatory guidance, typical design involves the use of undervoltage relays which, when actuated, automatically disconnect the safety buses from the degraded offsite power supply and initiate reconnection to an alternate supply such as the diesel-generator. This automatic disconnection creates the risk of an unwanted separation from the offsite power supply. Although the industry recognizes the importance of ensuring that adequate voltage is supplied to critical plant equipment, the method of achieving this goal is a matter of ongoing discussion. The potential benefits of degraded voltage relaying schemes do not necessarily outweigh the additional risks that they create, and other measures not explicitly described in the regulations, including detailed analyzes of the transmission grid and onsite distribution system, and procedural controls, are essential elements of a reliable offsite power supply. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Kueck, JD (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. NR 12 TC 2 Z9 2 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 2001 VL 16 IS 4 BP 374 EP 379 DI 10.1109/60.969478 PG 6 WC Energy & Fuels; Engineering, Electrical & Electronic SC Energy & Fuels; Engineering GA 501ET UT WOS:000172670300011 ER PT J AU Shaneyfelt, MR AF Shaneyfelt, MR TI 2001 IEEE Nuclear and Space Radiation Effects Conference (NSREC) General Chairman's Comments SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Editorial Material C1 Sandia Natl Labs, Livermore, CA 94550 USA. RP Shaneyfelt, MR (reprint author), Sandia Natl Labs, Livermore, CA 94550 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 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD DEC PY 2001 VL 48 IS 6 BP 1750 EP 1751 AR PII S0018-9499(01)10541-1 DI 10.1109/TNS.2001.983121 PN 1 PG 2 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 521UT UT WOS:000173860300002 ER PT J AU Funsten, HO Ritzau, SM Harper, RW Korde, R AF Funsten, HO Ritzau, SM Harper, RW Korde, R TI Response of 100% internal carrier collection efficiency silicon photodiodes to low-energy ions SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 38th Annual Nuclear and Space Radiation Effects Conference (NSREC) CY JUL 16-20, 2001 CL VANCOUVER, CANADA SP IEEE DE electronic energy loss; ion radiation; ionizing radiation; nuclear energy loss; photodiodes; radiation effects; silicon detectors ID PULSE-HEIGHT DEFECT; HEAVY-IONS; QUANTUM EFFICIENCY; RANGE PARAMETERS; SI DETECTORS; DAMAGE; SEMICONDUCTORS; RADIATION; DEVICES AB We measure the response of silicon photodiodes to irradiation by H+, He+, C+, N+, O+, Ne+, and Ar+ ions with energies up to 60 keV. The unique properties of these photodiodes, including an ultrathin SiO2 dead layer and 100% internal carrier collection efficiency, allow direct measurement of the total energy lost to nuclear (nonionizing) and electronic (ionizing) energy loss processes, which are important for quantifying effects such as damage and charge deposition. When plotted as a function of E/mZ(1/2), where E, m, and Z are the incident ion energy, mass, and atomic number, respectively, the responsivity is found to follow a single curve that represents all ion species and energies used in this study. This enables rapid, accurate estimation of damage and charge deposition by an ion as a function of penetration depth in silicon. A comparison of the measurements with the stopping and range of ions in matter (SRIM) Monte Carlo simulation code shows that SRIM significantly overestimates the fraction of the incident energy lost to electronic stopping processes for E/mZ(1/2) < 2 keV/amu. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Int Radiat Detectors, Torrance, CA 90505 USA. RP Funsten, HO (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. RI Funsten, Herbert/A-5702-2015 OI Funsten, Herbert/0000-0002-6817-1039 NR 33 TC 14 Z9 15 U1 0 U2 6 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 2001 VL 48 IS 6 BP 1785 EP 1789 AR PII S0018-9499(01)10531-9 DI 10.1109/23.983131 PN 1 PG 5 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 521UT UT WOS:000173860300007 ER PT J AU Dodd, PE Shaneyfelt, MR Fuller, E Pickel, JC Sexton, FW Winokur, PS AF Dodd, PE Shaneyfelt, MR Fuller, E Pickel, JC Sexton, FW Winokur, PS TI Impact of substrate thickness on single-event effects in integrated circuits SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 38th Annual Nuclear and Space Radiation Effects Conference (NSREC) CY JUL 16-20, 2001 CL VANCOUVER, CANADA SP IEEE ID PARTICLE-INDUCED LATCHUP; CMOS SRAMS; TECHNOLOGY; SEU AB The effects of substrate and epitaxial-layer thickness on the single-event upset and single-event latchup response of integrated circuits are studied using experiments and three-dimensional device simulations. Reducing substrate thickness can be an effective method for improving single-event upset and latchup immunity, but only if devices are thinned beyond their epitaxial-layer thickness. Increases in overall single-event upset threshold linear energy transfer of more than a factor of two are predicted after thinning to a wafer thickness of 0.5 mum. Simulations predict that the single-event latchup performance of a thinned integrated circuit will be similar to that of the same integrated circuit fabricated on an epitaxial substrate of equivalent thickness. By combining wafer thinning with backside contact formation, more significant improvements in the single-event latchup threshold can be obtained. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Novus Technol, Albuquerque, NM 87123 USA. PR&T Consulting, Bonsall, CA 92003 USA. RP Dodd, PE (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 25 TC 13 Z9 13 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 2001 VL 48 IS 6 BP 1865 EP 1871 AR PII S 0018-9499(01)10662-3 DI 10.1109/23.983144 PN 1 PG 7 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 521UT UT WOS:000173860300019 ER PT J AU Dodd, PE Shaneyfelt, MR Horn, KM Walsh, DS Hash, GL Hill, TA Draper, BL Schwank, JR Sexton, FW Winokur, PS AF Dodd, PE Shaneyfelt, MR Horn, KM Walsh, DS Hash, GL Hill, TA Draper, BL Schwank, JR Sexton, FW Winokur, PS TI SEU-sensitive volumes in bulk and SOISRAMs from first-principles calculations and experiments SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 38th Annual Nuclear and Space Radiation Effects Conference (NSREC) CY JUL 16-20, 2001 CL VANCOUVER, CANADA SP IEEE ID CHARGE COLLECTION; CROSS-SECTIONS; HEAVY-IONS; TECHNOLOGIES; SIMULATION; CIRCUITS; DEVICES; IMPACT; SRAMS AB Large-scale three-dimensional (3-D) device simulations, focused ion microscopy, and broadbeam heavy-ion experiments are used to determine and compare the SEU-sensitive volumes of bulk-Si and SOI CMOS SRAMs. Single-event upset maps and cross-section curves calculated directly from 3-D simulations show excellent agreement with broadbeam cross section curves and microbeam charge collection and upset images for 16 K bulk-Si SRAMs. Charge-collection and single-event upset (SEU) experiments on 64 K and 1 M SOI SRAMs indicate that drain strikes can cause single-event upsets in SOI ICs. 3-D simulations do not predict this result, which appears to be due to anomalous charge collection from the substrate through the buried oxide. This substrate charge-collection mechanism can considerably increase the SEU-sensitive volume of SOI SRAMs, and must be included in single-event models if they are to provide accurate predictions of SOI device response in radiation environments. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Dodd, PE (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 36 TC 112 Z9 119 U1 0 U2 11 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 2001 VL 48 IS 6 BP 1893 EP 1903 AR PII S 0018-9499(01)10667-2 DI 10.1109/23.983148 PN 1 PG 11 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 521UT UT WOS:000173860300023 ER PT J AU Massengill, LW Choi, BK Fleetwood, DM Schrimpf, RD Galloway, KF Shaneyfelt, MR Meisenheimer, TL Dodd, PE Schwank, JR Lee, YM Johnson, RS Lucovsky, G AF Massengill, LW Choi, BK Fleetwood, DM Schrimpf, RD Galloway, KF Shaneyfelt, MR Meisenheimer, TL Dodd, PE Schwank, JR Lee, YM Johnson, RS Lucovsky, G TI Heavy-ion-induced breakdown in ultra-thin gate oxides and high-k dielectrics SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 38th Annual Nuclear and Space Radiation Effects Conference (NSREC) CY JUL 16-20, 2001 CL VANCOUVER, CANADA SP IEEE DE dielectric breakdown; dielectric reliability; scaling; single-event radiation effects ID VERTICAL POWER MOSFETS; LEAKAGE CURRENT; SOFT BREAKDOWN; HARD-ERRORS; RUPTURE; IRRADIATION AB We present experimental results on single-event-induced breakdown in sub-5-nm plasma-enhanced SiO2, nitrided SiO2, Al2O3, HfO2, and Zr0.4Si1.6O4 dielectrics typical of current and future-generation commercial gate oxides. These advanced oxides are found to be quite resistant to ion-induced breakdown. Radiation-induced soft breakdown was observed in some films with 342 MeV An (LET = 80 MeV/mg/cm(2)) but not 340 MeV I (LET = 60 MeV/mg/cm(2)). The critical voltage to hard breakdown was found to scale with the square root of the physical oxide thickness, not with the energy stored on the gate capacitance. Alternative dielectrics with equivalent oxide thickness substantially below their physical thickness were found to exhibit significantly higher voltage to hard breakdown than SiO2 counterparts. All of the samples reached ion-induced hard breakdown at applied voltages well above typical operating power-supply voltages; these findings bode well for the use of advanced commercial integrated circuits in space systems. C1 Vanderbilt Univ, Dept Elect Engn & Comp Sci, Nashville, TN 37235 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. N Carolina State Univ, Dept Elect & Comp Engn, Raleigh, NC 27695 USA. N Carolina State Univ, Dept Phys, Raleigh, NC 27695 USA. RP Massengill, LW (reprint author), Vanderbilt Univ, Dept Elect Engn & Comp Sci, 221 Kirkland Hall, Nashville, TN 37235 USA. RI Schrimpf, Ronald/L-5549-2013; OI Schrimpf, Ronald/0000-0001-7419-2701; Choi, Bo K./0000-0002-4984-5958 NR 27 TC 46 Z9 46 U1 2 U2 14 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 2001 VL 48 IS 6 BP 1904 EP 1912 AR PII S 0018-9499(01)10668-4 DI 10.1109/23.983149 PN 1 PG 9 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 521UT UT WOS:000173860300024 ER PT J AU Boruta, N Lum, GK O'Donnell, H Robinette, L Shaneyfelt, MR Schwank, JR AF Boruta, N Lum, GK O'Donnell, H Robinette, L Shaneyfelt, MR Schwank, JR TI A new physics-based model for understanding single-event gate rupture in linear devices SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 38th Annual Nuclear and Space Radiation Effects Conference (NSREC) CY JUL 16-20, 2001 CL VANCOUVER, CANADA SP IEEE DE dielectric breakdown; heavy ion; linear devices; oxide breakdown; single-event gate rupture (SEGR) ID POWER MOSFETS; OXIDES; EXPRESSION AB This paper presents a new physics-based model for understanding the basic mechanism of single-event gate rupture (SEGR) in analog devices. This model accounts for the different competing physics mechanisms, such as carrier drift, diffusion, recombination in the drift diffusion, and Poisson's equations, to explain the dependence of SEGR on biasing voltage, cross section, and critical electric field strength. Hence, the model provides a more accurate method of understanding and predicting the breakdown of oxides from heavy-ion strikes. C1 Lockheed Martin Space Syst Co, Sunnyvale, CA 94088 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Boruta, N (reprint author), Lockheed Martin Space Syst Co, Sunnyvale, CA 94088 USA. NR 13 TC 28 Z9 28 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 2001 VL 48 IS 6 BP 1917 EP 1924 AR PII S 0018-9499(01)10670-2 DI 10.1109/23.983151 PN 1 PG 8 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 521UT UT WOS:000173860300026 ER PT J AU Castellani-Coulie, K Palau, JM Hubert, G Calvet, MC Dodd, PE Sexton, F AF Castellani-Coulie, K Palau, JM Hubert, G Calvet, MC Dodd, PE Sexton, F TI Various SEU conditions in SRAM studied by 3-D device simulation SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 38th Annual Nuclear and Space Radiation Effects Conference (NSREC) CY JUL 16-20, 2001 CL VANCOUVER, CANADA SP IEEE DE critical charge; device simulation; sensitive regions; single-event upset (SEU); SEU mechanisms; SRAM sensitivity ID SINGLE EVENT UPSET; STATIC RAMS; CHARGE; FLIGHT AB Various single-event upset (SEU) conditions are studied by three-dimensional device simulation with the purpose of going deeply into the understanding of the mechanisms governing the SEU sensitivity for a large variety of tracks. The results give a better view of what regions are sensitive. They clearly point out that some generally accepted notions must be revised as considering the normal incidence case to be the most sensitive or neglecting PMOS contribution. C1 Univ Montpellier 2, F-34095 Montpellier 05, France. Sandia Natl Labs, Albuquerque, NM 87185 USA. EADS, LV, F-78133 Les Mureaux, France. RP Castellani-Coulie, K (reprint author), Univ Montpellier 2, CEM2, F-34095 Montpellier 05, France. RI Castellani-Coulie, Karine/G-7727-2011 NR 16 TC 29 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 0018-9499 J9 IEEE T NUCL SCI JI IEEE Trans. Nucl. Sci. PD DEC PY 2001 VL 48 IS 6 BP 1931 EP 1936 AR PII S0018-9499(01)10672-6 DI 10.1109/23.983153 PN 1 PG 6 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 521UT UT WOS:000173860300028 ER PT J AU Neal, JS Townsend, LW AF Neal, JS Townsend, LW TI Predicting dose-time profiles of solar energetic particle events using Bayesian forecasting methods SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 38th Annual Nuclear and Space Radiation Effects Conference (NSREC) CY JUL 16-20, 2001 CL VANCOUVER, CANADA SP IEEE DE Bayesian interface; dose prediction; solar particle events ID DISTRIBUTIONS; PARAMETERIZATION AB Bayesian inference techniques, coupled with Markov chain Monte Carlo sampling methods, are used to predict dose-time profiles for energetic solar particle events. Inputs into the predictive methodology are dose and dose-rate measurements obtained early in the event. Surrogate dose values are grouped in hierarchical models to express relationships among similar solar particle events. Models assume nonlinear, sigmoidal growth for dose throughout an event. Markov chain Monte Carlo methods are used to sample from Bayesian posterior predictive distributions for dose and dose rate. Example predictions are provided for the November 8, 2000, and August 12, 1989, solar particle events. C1 Univ Tennessee, Dept Nucl Engn, Knoxville, TN 37996 USA. RP Neal, JS (reprint author), Oak Ridge Natl Lab, Nucl Sci & Technol Div, Oak Ridge, TN 37831 USA. RI Neal, John/R-8203-2016 OI Neal, John/0000-0001-8337-5235 NR 19 TC 11 Z9 11 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 2001 VL 48 IS 6 BP 2004 EP 2009 AR PII S0018-9499(01)10682-9 DI 10.1109/23.983163 PN 1 PG 6 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 521UT UT WOS:000173860300038 PM 12033225 ER PT J AU Maurer, RH Roth, DR Kinnison, JD Jordan, TA Heilbronn, LH Miller, J Zeitlin, CJ AF Maurer, RH Roth, DR Kinnison, JD Jordan, TA Heilbronn, LH Miller, J Zeitlin, CJ TI Neutron production from polyethylene and common spacecraft materials SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 38th Annual Nuclear and Space Radiation Effects Conference (NSREC) CY JUL 16-20, 2001 CL VANCOUVER, CANADA SP IEEE DE high-energy neutrons; neutron moderation; polyethylene AB We report experimental measurements of neutron production from collisions of neutron beams with polyethylene blocks simulating tissue at the Los Alamos National Laboratory Neutron Science Center and 1 GeV/amu iron nuclei with spacecraft shielding materials at the Brookhaven National Laboratory AGS. C1 Johns Hopkins Univ, Appl Phys Lab, Laurel, MD 20723 USA. Expt & Math Phys Consultants, Gaithersburg, MD 20885 USA. Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Maurer, RH (reprint author), Johns Hopkins Univ, Appl Phys Lab, Johns Hopkins Rd, Laurel, MD 20723 USA. RI Heilbronn, Lawrence/J-6998-2013 OI Heilbronn, Lawrence/0000-0002-8226-1057 NR 6 TC 6 Z9 6 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 2001 VL 48 IS 6 BP 2029 EP 2033 AR PII S0018-9499(01)10686-6 DI 10.1109/23.983167 PN 1 PG 5 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 521UT UT WOS:000173860300042 PM 12033226 ER PT J AU Rashkeev, SN Fleetwood, DM Schrimpf, RD Pantelides, ST AF Rashkeev, SN Fleetwood, DM Schrimpf, RD Pantelides, ST TI Proton-induced defect generation at the Si-SiO2 interface SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 38th Annual Nuclear and Space Radiation Effects Conference (NSREC) CY JUL 16-20, 2001 CL VANCOUVER, CANADA SP IEEE DE centers; devices; oxide; radiation; silicon ID FIRST-PRINCIPLES CALCULATIONS; TRAP FORMATION; CRYSTALLINE SILICON; MOLECULAR-HYDROGEN; TIME-DEPENDENCE; MOBILE PROTONS; MOS STRUCTURES; H+ MOTION; SIO2; STATES AB We report first-principles calculations of interface-trap formation in MOS structures. Hydrogen is known to passivate Si dangling bonds at the Si-SiO2 interface, but the subsequent arrival of H+ at the interface causes depassivation of Si-H bonds. We show that, contrary to conventional assumptions, depassivation is not a two-step process, namely, neutralization of H+ by a Si electron, reaction with a Si-H bond, and subsequent formation of an H-2 molecule. Instead, we establish that H+ is the only stable charge state of hydrogen at the interface, and that H+ reacts directly with Si-H. The products of this reaction are an H-2 molecule and a positively charged dangling bond center (D+), formed via the reaction SiH + H+ = > D+ + H-2. Here the D+ center is most likely the positive charge state of the P-b defect. As a result, H-induced interface-trap formation depends on the electric field in the oxide to establish a preferred direction for proton drift, but does not depend on the availability of Si electrons to enable the interface reaction to occur. After the dangling bond center is formed via this process, the subsequent charge state of the interface traps is controlled by the Si surface potential. A hydrogen catalytic cycle can lead to reversible passivation and depassivation reactions at or near the interface, depending on experimental conditions. C1 Vanderbilt Univ, Dept Phys & Astron, Nashville, TN 37235 USA. Vanderbilt Univ, Dept Elect Engn & Comp Sci, Nashville, TN 37235 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Rashkeev, SN (reprint author), Vanderbilt Univ, Dept Phys & Astron, Nashville, TN 37235 USA. RI Schrimpf, Ronald/L-5549-2013 OI Schrimpf, Ronald/0000-0001-7419-2701 NR 54 TC 41 Z9 45 U1 0 U2 9 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 2001 VL 48 IS 6 BP 2086 EP 2092 AR PII S0018-9499(01)10648-9 DI 10.1109/23.983177 PN 1 PG 7 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 521UT UT WOS:000173860300052 ER PT J AU Felix, JA Fleetwood, DM Riewe, LC Shaneyfelt, MR Winokur, PS AF Felix, JA Fleetwood, DM Riewe, LC Shaneyfelt, MR Winokur, PS TI Bias and frequency dependence of radiation-induced charge trapping in MOS devices SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 38th Annual Nuclear and Space Radiation Effects Conference (NSREC) CY JUL 16-20, 2001 CL VANCOUVER, CANADA SP IEEE DE electron traps; hole traps; modeling; radiation effects; thermally stimulated currents ID THERMALLY-STIMULATED-CURRENT; BORDER TRAPS; INTERFACE STATES; PHOTON ENERGY; CAPACITORS; OXIDE; BUILDUP; CO-60; IRRADIATIONS; TEMPERATURE AB Trapped-charge densities in 45-mn radiation-hardened MOS oxides were characterized after 0.1 Hz to 1.0 MHz ac bias irradiations using thermally stimulated-current (TSC) and capacitance-voltage (C-V) techniques. We find no significant frequency dependence for the buildup of trapped positive or negative charge in these oxides. Trapped positive charge densities during ac bias exposures are similar to densities during dc bias exposures at the same average applied field during irradiation, but trapped negative charge densities do not scale as simply with average electric field. The majority of negative trapped charge is part of a stable dipole defect, which evidently forms very quickly (<1 mus) after the creation of an electron-hole pair in a region of localized space charge. Over the entire frequency range for these devices, the trapped electrons compensate 60 +/- 5% of the trapped positive charge for 5 V/0 V exposures and 70 +/- 6% of the positive charge for 5 V/-5 V exposures. These data agree well with de bias irradiations of these devices, in which trapped electrons compensate 59 +/- 4% of the trapped positive charge under positive bias and 76 +/- 2% at zero or negative bias, suggesting an enhancement of electron-hole dipole formation at small or negative electric fields. Mechanisms are discussed for the creation of dipoles in SiO2, and our results are compared with previous studies of the field dependence of electron-hole recombination rates. Implications for total dose modeling are discussed. C1 Vanderbilt Univ, Dept Comp Sci & Elect Engn, Nashville, TN 37235 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Felix, JA (reprint author), Vanderbilt Univ, Dept Comp Sci & Elect Engn, 221 Kirkland Hall, Nashville, TN 37235 USA. NR 30 TC 4 Z9 6 U1 0 U2 10 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 2001 VL 48 IS 6 BP 2114 EP 2120 AR PII S0018-9499(01)10652-0 DI 10.1109/23.983181 PN 1 PG 7 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 521UT UT WOS:000173860300056 ER PT J AU Schwank, JR Shaneyfelt, MR Paillet, P Beutler, DE Ferlet-Cavrois, V Draper, BL Loemker, RA Dodd, PE Sexton, FW AF Schwank, JR Shaneyfelt, MR Paillet, P Beutler, DE Ferlet-Cavrois, V Draper, BL Loemker, RA Dodd, PE Sexton, FW TI Optimum laboratory radiation source for hardness assurance testing SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 38th Annual Nuclear and Space Radiation Effects Conference (NSREC) CY JUL 16-20, 2001 CL VANCOUVER, CANADA SP IEEE ID X-RAY; MOS DEVICES; CO-60; IRRADIATIONS; TRANSISTORS; ELECTRONICS AB Silicon-on-insulator (SOI) and bulk-silicon transistors were irradiated using X-ray, Co-60 gamma, and proton radiation sources. Co-60 gamma irradiation generates larger radiation-induced threshold voltage shifts (by a factor of two) in SOI buried oxides and in parasitic field oxides under low-field conditions than X-ray or proton irradiation. For all devices examined, the radiation-induced threshold voltage shifts generated by X-ray irradiation were equal to, within experimental uncertainty, the radiation-induced threshold voltage shifts generated by proton irradiation. The differences in threshold voltage shifts, for the different radiation sources are attributed to differences in stopping power and consequently charge yield. The results suggest that for simulating proton-rich space environments, X-ray laboratory radiation sources are better suited for hardness assurance testing than Co-60 gamma radiation sources. Using Co-60 gamma sources for hardness assurance testing will result in more conservative estimates of device failure levels. Thus, our results do not preclude the use of Co-60 gamma radiation sources for hardness assurance testing for proton-rich environments. For electron-rich space environments, Co-60 gamma radiation sources may be better suited for hardness assurance testing. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. CEA, DIF, F-91680 Bruyeres Le Chatel, France. RP Schwank, JR (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 20 TC 23 Z9 23 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 2001 VL 48 IS 6 BP 2152 EP 2157 AR PII S0018-9499(01)10659-3 DI 10.1109/23.983188 PN 1 PG 6 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 521UT UT WOS:000173860300063 ER PT J AU Zhu, XW Bhuva, B Cirba, CR Massengill, L Buchner, S Dodd, PE AF Zhu, XW Bhuva, B Cirba, CR Massengill, L Buchner, S Dodd, PE TI A methodology for identifying laser parameters for equivalent heavy-ion hits SO IEEE TRANSACTIONS ON NUCLEAR SCIENCE LA English DT Article; Proceedings Paper CT 38th Annual Nuclear and Space Radiation Effects Conference (NSREC) CY JUL 16-20, 2001 CL VANCOUVER, CANADA SP IEEE ID PULSED-LASER; CHARGE COLLECTION; CMOS SRAMS; SEU AB Pulsed lasers show excellent promise for single-event upset (SEU) studies in laboratory environments due to their simplicity of use. However, a one-to-one relationship between a laser hit and a heavy-ion hit has not been developed so far. With the assumption that the collected charge from a SEU hit dictates the circuit-level response, equivalency between a laser hit and heavy-ion hit can be established if the collected charge from both hits is identical. This paper presents a methodology to identify the equivalent laser characteristics for a heavy-ion hit by calculating the collected charge through device-level simulations. Such knowledge will enable SEU hardness assurance of circuits using lasers. C1 Vanderbilt Univ, Dept Elect Engn & Comp Sci, Nashville, TN 37235 USA. SFA, NRL, Washington, DC 20375 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Zhu, XW (reprint author), Vanderbilt Univ, Dept Elect Engn & Comp Sci, 221 Kirkland Hall, Nashville, TN 37235 USA. NR 13 TC 7 Z9 7 U1 3 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 2001 VL 48 IS 6 BP 2174 EP 2179 AR PII S0018-9499(01)10708-2 DI 10.1109/23.983192 PN 1 PG 6 WC Engineering, Electrical & Electronic; Nuclear Science & Technology SC Engineering; Nuclear Science & Technology GA 521UT UT WOS:000173860300067 ER PT J AU Guerra, C Pascucci, V AF Guerra, C Pascucci, V TI Finding line segments with tabu search SO IEICE TRANSACTIONS ON INFORMATION AND SYSTEMS LA English DT Letter DE 3D line detection; range images; tabu search AB The problem of detecting straight lines arises frequently in image processing and computer vision. Here we consider the problem of extracting lines from range images and more generally from sets of three-dimensional (3D) points. The problem is stated as follows. Given a set Gamma of points in 3D space and a non-negative constant e, determine the line that is at a distance at most e from the maximal number of points of Gamma. The extraction of multiple lines is achieved iteratively by performing this best line detection and removing at each iteration the points that are close to the line found. We consider two approaches to solve the problem. The first is a simple approach that selects the best line among a randomly chosen subset of lines each defined by a pair of edge points, The second approach, based on tabu search, explores a larger set of candidate lines thus obtaining a better fit of the lines to the points. We present experimental results on different typos of three-dimensional data (i) range images of polyhedral objects (II) secondary structures (helices and strands) of large molecules. C1 Univ Padua, Padua, Italy. Purdue Univ, W Lafayette, IN 47907 USA. Lawrence Livermore Natl Lab, CASC, Livermore, CA USA. RP Guerra, C (reprint author), Univ Padua, Padua, Italy. NR 15 TC 3 Z9 3 U1 0 U2 0 PU IEICE-INST ELECTRONICS INFORMATION COMMUNICATIONS ENG PI TOKYO PA KIKAI-SHINKO-KAIKAN BLDG MINATO-KU SHIBAKOEN 3 CHOME, TOKYO, 105, JAPAN SN 0916-8532 J9 IEICE T INF SYST JI IEICE Trans. Inf. Syst. PD DEC PY 2001 VL E84D IS 12 BP 1739 EP 1744 PG 6 WC Computer Science, Information Systems; Computer Science, Software Engineering SC Computer Science GA 504UM UT WOS:000172874300022 ER PT J AU Wright, JL Zhu, JH Horton, JA Heatherly, L AF Wright, JL Zhu, JH Horton, JA Heatherly, L TI Effect of boron doping on the mechanical properties of ordered Ni-Mo alloys SO INTERMETALLICS LA English DT Article DE intermetallics, miscellaneous; mechanical properties at ambient temperature; environmental embrittlement ID INTERGRANULAR HYDROGEN EMBRITTLEMENT; ROOM-TEMPERATURE DUCTILITY; GRAIN-BOUNDARY FRACTURE; ENVIRONMENTAL EMBRITTLEMENT; WATER-VAPOR; NI3AL; FEAL; FE3AL; CO3TI; ALUMINIDES AB HASTELLOY B-2 alloy was found to exhibit environmental embrittlement when tested in air and hydrogen at ambient temperature after atomic ordering introduced by a heat treatment at 700 degreesC for 24 h. Molybdenum in the HASTELLOY B-2 alloy was probably reactive enough to dissociate water vapor in air to generate atomic hydrogen, resulting in hydrogen embrittlement. The percentage of transgranular fracture increased as the test environment changed from hydrogen gas to moist air or water vapor, and vacuum or oxygen. With the addition of 100 wt ppm B, the environmental embrittlement was completely eliminated, with the tensile properties independent of both test environment and strain rate. The fracture mode remained the same, i.e. ductile dimpling, after B-doping when tested in different environments. The immunity of the B-doped B2 alloy to environmental sensitivity remained even after long-term heat treatment. Auger analysis does not detect any boron segregation at the grain boundaries. The mechanism of boron doping in eliminating the environmental embrittlement in the Ni-Mo alloy is apparently different from that in many L1(2)-type alloys such as Ni3Al and Ni3Si. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Oak Ridge Natl Lab, Met & Ceram Div, Oak Ridge, TN 37831 USA. Tennessee Technol Univ, Dept Mech Engn, Cookeville, TN 38505 USA. RP Wright, JL (reprint author), Oak Ridge Natl Lab, Met & Ceram Div, Mail Stop 6115, Oak Ridge, TN 37831 USA. NR 40 TC 4 Z9 4 U1 0 U2 2 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0966-9795 J9 INTERMETALLICS JI Intermetallics PD DEC PY 2001 VL 9 IS 12 BP 1021 EP 1028 DI 10.1016/S0966-9795(01)00071-1 PG 8 WC Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering GA 499AK UT WOS:000172547100004 ER PT J AU Kimura, Y Mishima, Y Liu, CT AF Kimura, Y Mishima, Y Liu, CT TI Microstructure control and tensile properties of three-phase alloys based on the E2(1) Co3AlC and B2CoAl SO INTERMETALLICS LA English DT Article DE intermetallics, miscellaneous; phase diagram; yield stress; mechanical testing; microscopy ID INTERMETALLIC COMPOUND COAL; MECHANICAL-PROPERTIES; AL-C; ORIENTATION DEPENDENCE; TEMPERATURE-DEPENDENCE; SINGLE-CRYSTALS; ORDERED ALLOYS; B2 COAL; STABILITY; BEHAVIOR AB To investigate tensile mechanical behavior, tensile tests were conducted at room temperature and 1273 K on three-phase alloys consisting of the E2(1) Co3AlC, B2 CoAl and (Co) primary solid solution. The alloy containing a large volume fraction of E21 phase exhibits excellent ductility, exceeding 5% plastic strain at room temperature, while the alloy with a,considerable amount of coarse B2 phase particles shows zero ductility. In this study, microstructure control was used to improve the ambient temperature ductility of the E2(1)/B2/(Co) three-phase alloys. Hot forging and subsequent heat treatments were performed aiming at eliminating solidification defects and minimizing the heterogeneity of the as-cast microstructure. These thermomechanical treatments together with compositional control effectively improve the ductility of the E2(1)/B2/(Co) three-phase alloys at ambient temperature and 1273 K. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Tokyo Inst Technol Mat Sci & Engn, Midori Ku, Yokohama, Kanagawa 2268502, Japan. Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Kimura, Y (reprint author), Tokyo Inst Technol Mat Sci & Engn, Midori Ku, 4259 Nagatsuta, Yokohama, Kanagawa 2268502, Japan. OI Liu, Chain Tsuan/0000-0001-7888-9725 NR 47 TC 15 Z9 15 U1 0 U2 0 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0966-9795 J9 INTERMETALLICS JI Intermetallics PD DEC PY 2001 VL 9 IS 12 BP 1069 EP 1078 DI 10.1016/S0966-9795(01)00113-3 PG 10 WC Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering GA 499AK UT WOS:000172547100010 ER PT J AU Krokidis, X Moriarty, NW Lester, WA Frenklach, M AF Krokidis, X Moriarty, NW Lester, WA Frenklach, M TI A quantum Monte Carlo study of energy differences in C4H3 and C4H5 isomers SO INTERNATIONAL JOURNAL OF CHEMICAL KINETICS LA English DT Article ID ELECTRON LOCALIZATION FUNCTION; TOPOLOGICAL ANALYSIS; MOLLER-PLESSET; THEORETICAL PROCEDURES; GAUSSIAN-2 THEORY; WAVE-FUNCTIONS; 2ND-ROW ATOMS; BASIS-SETS; ACETYLENE; THERMOCHEMISTRY AB Quantum Monte Carlo and a series of other ab initio as well as density functional theory calculations were performed for the enthalpy of formation of C4H3 and C4H5 radicals. The computed Delta H-f(298)0 values, in kcal/mol, are 126.0 for n-C4H3, 119.4 for i-C4H3, 83.4 for n-C4H5, and 76.2 for i-C4H5, all with one standard deviation of 0.6 kcal/mol.The enthalpy differences between the n and i isomers of C4H3 and C4H5 are predicted to be substantially lower than those obtained in recent theoretical studies. The nature of the middle C-C bond in these radicals was examined using the electron localization function topological analysis performed by bonding evolution theory for partitioning the molecular space into regions with clear chemical meaning. This analysis shows that the n isomers are represented by a unique Lewis structure while the i isomers are represented by a resonance description, For the latter systems, the middle C-C bond is only mildly conjugated and the corresponding degree of conjugation is calculated. These results signify higher prominence of the even-carbon-atom reaction pathways in the formation of the first aromatic ring. in hydrocarbon pyrolysis and oxidation, consistent with the past kinetic modeling and recent experimental studies. (C) 2001 John Wiley & Sons, Inc.* C1 Accelrys Inc, F-91898 Orsay, France. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Phys Biosci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Mech Engn, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Environm Energy Technol Div, Berkeley, CA 94720 USA. RP Frenklach, M (reprint author), Accelrys Inc, Parc Club Orsay Univ,20 Rue Jean Rostand, F-91898 Orsay, France. NR 48 TC 18 Z9 18 U1 0 U2 2 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0538-8066 J9 INT J CHEM KINET JI Int. J. Chem. Kinet. PD DEC PY 2001 VL 33 IS 12 BP 808 EP 820 DI 10.1002/kin.10004 PG 13 WC Chemistry, Physical SC Chemistry GA 494BK UT WOS:000172258300006 ER PT J AU Kiefer, JH Tranter, RS Wang, H Wagner, AF AF Kiefer, JH Tranter, RS Wang, H Wagner, AF TI Thermodynamic functions for the cyclopentadienyl radical: The effect of Jahn-Teller distortion SO INTERNATIONAL JOURNAL OF CHEMICAL KINETICS LA English DT Article AB We report CASSCF/cc-PVDZ calculations of the potential surface for the title Jahn-Teller molecule. Energies are calculated along all normal coordinates that can be affected by Jahn-Teller distortion. Both the E'(2) in-plane bend and stretch modes are found to be involved, but the bend contribution is very small and its contribution to the entropy is negligible. The in-plane stretch modes strongly dominate, affording a maximum stabilization energy of 4.73 kcal/mol. Harmonic frequencies are calculated for the other modes in the D-5h configuration, and these, are scaled in accordance with a comparison of experimental frequencies with similar calculations on cyclopentadiene. Energy levels for nuclear motion in the Jahn-Teller modes are then determined using the calculated surface, and these are combined with the scaled harmonic frequencies to obtain complete thermodynamic functions for the radical. The results are then fit to both the NASA polynomial form and a compact power series in inverse temperature for modeling applications. Because of changes in degeneracy and symmetry number. the entropy is actually lower than previous estimates. Nonetheless, the effect of the pseudorotation on the entropy is noticeable over the entire span of temperatures. This work is evidently the first to present both energy levels and thermodynamic functions for a Jahn-Teller molecule derived from a complete and consistent theoretical treatment, (C) 2001 John Wiley & Sons, Inc. C1 Univ Illinois, Dept Chem Engn, Chicago, IL 60680 USA. Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. Univ Delaware, Dept Mech Engn, Newark, DE 19716 USA. RP Univ Illinois, Dept Chem Engn, Chicago, IL 60680 USA. EM kiefer@uic.edu RI Wang, Hai/A-1292-2009 OI Wang, Hai/0000-0001-6507-5503 NR 33 TC 24 Z9 24 U1 1 U2 9 PU WILEY-BLACKWELL PI HOBOKEN PA 111 RIVER ST, HOBOKEN 07030-5774, NJ USA SN 0538-8066 EI 1097-4601 J9 INT J CHEM KINET JI Int. J. Chem. Kinet. PD DEC PY 2001 VL 33 IS 12 BP 834 EP 845 DI 10.1002/kin.10006 PG 12 WC Chemistry, Physical SC Chemistry GA 494BK UT WOS:000172258300008 ER PT J AU Westbrook, CK Pitz, WJ Curran, HJ Boercker, J Kunrath, E AF Westbrook, CK Pitz, WJ Curran, HJ Boercker, J Kunrath, E TI Chemical kinetic modeling study of shock tube ignition of heptane isomers SO INTERNATIONAL JOURNAL OF CHEMICAL KINETICS LA English DT Article ID OXIDATION; COMBUSTION; MOLECULES; MECHANISM; MIXTURES; PROPANE; METHANE; ETHANE AB High-temperature detailed chemical kinetic reaction mechanisms are developed for all nine chemical isomers of heptane (C7H16), following techniques and models developed previously for other smaller alkane hydrocarbon species. These reaction mechanisms are tested by computing shock tube ignition delay times for stoichiometric heptane/oxygen mixtures diluted by argon. Although no corresponding experiments have been reported in the literature for most of these isomers of heptane, intercomparisons, between the computed results for these isomers and comparisons with available experimental results for other alkane fuels are used to validate the reaction mechanisms as much as possible. Differences in the overall reaction rates of these heptane isomers are discussed in terms of differences in their molecular structure and the resulting variations in rates of important chain branching and termination reactions. The implications of these results regarding ignition of other alkane fuels are discussed. (C) 2001 John Wiley & Sons, Inc. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Galway Mayo Inst, Galway, Ireland. USAF Acad, Colorado Springs, CO 80840 USA. RP Westbrook, CK (reprint author), Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. EM westbrook1@llnl.gov OI Curran, Henry/0000-0002-5124-8562 NR 34 TC 48 Z9 49 U1 3 U2 13 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0538-8066 J9 INT J CHEM KINET JI Int. J. Chem. Kinet. PD DEC PY 2001 VL 33 IS 12 BP 868 EP 877 DI 10.1002/kin.10020 PG 10 WC Chemistry, Physical SC Chemistry GA 494BK UT WOS:000172258300012 ER PT J AU Watson, WD Ruppert, LF Bragg, LJ Tewalt, SJ AF Watson, WD Ruppert, LF Bragg, LJ Tewalt, SJ TI A geostatistical approach to predicting sulfur content in the Pittsburgh coal bed SO INTERNATIONAL JOURNAL OF COAL GEOLOGY LA English DT Article DE geostatistical analysis; Pittsburgh coal bed; comparison with mine data; kriging; statistical precision AB The US Geological Survey (USGS) is completing a national assessment of coal resources in the five top coal-producing regions in the US. Point-located data provide measurements on coal thickness and sulfur content. The sample data and their geologic interpretation represent the most regionally complete and up-to-date assessment of what is known about top-producing US coal beds. The sample data are analyzed using a combination of geologic and Geographic Information System (GIS) models to estimate tonnages and qualities of the coal beds. Traditionally, GIS practitioners use contouring to represent geographical patterns of "similar" data values. The tonnage and grade of coal resources are then assessed by using the contour lines as references for interpolation. An assessment taken to this point is only indicative of resource quantity and quality. Data users may benefit from a statistical approach that would allow them to better understand the uncertainty and limitations of the sample data. To develop a quantitative approach, geostatistics were applied to the data on coal sulfur content from samples taken in the Pittsburgh coal bed (located in the eastern US, in the southwestern part of the state of Pennsylvania, and in adjoining areas in the states of Ohio and West Virginia). Geostatistical methods that account for regional and local trends were applied to blocks 2.7 mi (4.3 km) on a side. The data and geostatistics support conclusions concerning the average sulfur content and its degree of reliability at regional- and economic-block scale over the large, contiguous part of the Pittsburgh outcrop, but not to a mine scale. To validate the method, a comparison was made with the sulfur contents in sample data taken from 53 coal mines located in the study area. The comparison showed a high degree of similarity between the sulfur content in the mine samples and the sulfur content represented by the geostatistically derived contours. Published by Elsevier Science B.V. C1 Energy Informat Adm, US DOE, Washington, DC 20585 USA. US Geol Survey, Natl Ctr, Reston, VA 20192 USA. RP Watson, WD (reprint author), Energy Informat Adm, US DOE, 950 Lenfant Plaza S Bldg EI-52,1000 Independence, Washington, DC 20585 USA. OI Ruppert, Leslie/0000-0002-7453-1061 NR 21 TC 12 Z9 13 U1 1 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0166-5162 J9 INT J COAL GEOL JI Int. J. Coal Geol. PD DEC PY 2001 VL 48 IS 1-2 BP 1 EP 22 DI 10.1016/S0166-5162(01)00035-0 PG 22 WC Energy & Fuels; Geosciences, Multidisciplinary SC Energy & Fuels; Geology GA 510VA UT WOS:000173226900001 ER PT J AU Murphy, M Mount, DM Gable, CW AF Murphy, M Mount, DM Gable, CW TI A point-placement strategy for Conforming Delaunay tetrahedralization SO INTERNATIONAL JOURNAL OF COMPUTATIONAL GEOMETRY & APPLICATIONS LA English DT Article DE Delaunay triangulations; unstructured mesh generation ID TRIANGULATIONS AB A strategy is presented to find a set of points that yields a Conforming Delaunay tetrahedralization of a three-dimensional Piecewise-Linear! complex (PLC). This algorithm is novel because it imposes no angle restrictions on the input PLC. In the process, an algorithm is described that computes a planar conforming Delaunay triangulation of a Planar Straight-Line Graph (PSLG) such that each triangle has a bounded circumradius, which may be of independent interest. C1 Univ Maryland, Dept Comp Sci, College Pk, MD 20742 USA. Univ Maryland, Inst Adv Comp Studies, College Pk, MD 20742 USA. Los Alamos Natl Lab, Div Earth & Environm Sci, Geoanal Grp, Los Alamos, NM 87544 USA. RP Murphy, M (reprint author), Univ Maryland, Dept Comp Sci, College Pk, MD 20742 USA. RI Gable, Carl/B-4689-2011; OI Gable, Carl/0000-0001-7063-0815 NR 21 TC 19 Z9 21 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 0218-1959 J9 INT J COMPUT GEOM AP JI Int. J. Comput. Geom. Appl. PD DEC PY 2001 VL 11 IS 6 BP 669 EP 682 DI 10.1142/S0218195901000699 PG 14 WC Computer Science, Theory & Methods; Mathematics, Applied SC Computer Science; Mathematics GA 508BP UT WOS:000173067600004 ER PT J AU Berman, F Chien, A Cooper, K Dongarra, J Foster, I Gannon, D Johnsson, L Kennedy, K Kesselman, C Mellor-Crummey, J Reed, D Torczon, L Wolski, R AF Berman, F Chien, A Cooper, K Dongarra, J Foster, I Gannon, D Johnsson, L Kennedy, K Kesselman, C Mellor-Crummey, J Reed, D Torczon, L Wolski, R TI The GrADS project: Software support for high-level grid application development SO INTERNATIONAL JOURNAL OF HIGH PERFORMANCE COMPUTING APPLICATIONS LA English DT Article ID I-WAY; ARCHITECTURE AB Advances in networking technologies will soon make it possible to use the global information infrastructure in a qualitatively different way-as a computational as well as an information resource. As described in the recent book The Grid: Blueprint for a New Computing Infrastructure, this Grid will connect the nation's computers, databases, instruments, and people in a seamless web of computing and distributed intelligence, which can be used in an on demand fashion as a problem-solving resource in many fields of human endeavor-and, in particular, science and engineering. The availability of grid resources will give rise to dramatically new classes of applications, in which computing resources are no longer localized but, rather, distributed, heterogeneous, and dynamic; computation is increasingly sophisticated and multidisciplinary; and computation is integrated into our daily lives and, hence, subject to stricter time constraints than at present. The impact of these new applications will be pervasive, ranging from new systems for scientific inquiry, through computing support for crisis management, to the use of ambient computing to enhance personal mobile computing environments. To realize this vision, significant scientific and technical obstacles must be overcome. Principal among these is usability. The goal of the Grid Application Development Software (GrADS) project is to simplify distributed heterogeneous computing in the same way that the World Wide Web simplified information sharing over the Internet. To that end, the project is exploring the scientific and technical problems that must be solved to make it easier for ordinary scientific users to develop, execute, and tune applications on the Grid. In this paper, the authors describe the vision and strategies underlying the GrADS project, including the base software architecture for grid execution and performance monitoring, strategies and tools for construction of applications from libraries of grid-aware components, and development of innovative new science and engineering applications that can exploit these new technologies to run effectively in grid environments. C1 Univ Tennessee, Dept Comp Sci, Knoxville, TN 37996 USA. Univ Calif San Diego, La Jolla, CA 92093 USA. Rice Univ, Houston, TX 77251 USA. Argonne Natl Lab, Argonne, IL 60439 USA. Univ Chicago, Chicago, IL 60637 USA. Indiana Univ, Bloomington, IN 47405 USA. Univ Houston, Houston, TX 77004 USA. Univ So Calif, Los Angeles, CA 90089 USA. Univ Illinois, Urbana, IL 61801 USA. Univ Calif Santa Barbara, Santa Barbara, CA 93106 USA. RP Dongarra, J (reprint author), Univ Tennessee, Dept Comp Sci, 1122 Volunteer Blvd,Suite 203, Knoxville, TN 37996 USA. EM dongarra@cs.utk.edu RI Dongarra, Jack/E-3987-2014; OI Kesselman, Carl/0000-0003-0917-1562 NR 61 TC 131 Z9 138 U1 0 U2 11 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 2001 VL 15 IS 4 BP 327 EP 344 DI 10.1177/109434200101500401 PG 18 WC Computer Science, Hardware & Architecture; Computer Science, Interdisciplinary Applications; Computer Science, Theory & Methods SC Computer Science GA 493NB UT WOS:000172228600001 ER PT J AU Allen, G Angulo, D Foster, I Lanfermann, G Liu, C Radke, T Seidel, E Shalf, J AF Allen, G Angulo, D Foster, I Lanfermann, G Liu, C Radke, T Seidel, E Shalf, J TI The cactus worm: Experiments with dynamic resource discovery and allocation in a grid environment SO INTERNATIONAL JOURNAL OF HIGH PERFORMANCE COMPUTING APPLICATIONS LA English DT Article ID IMPLEMENTATION AB The ability to harness heterogeneous, dynamically available grid resources, is attractive to typically resource-starved computational scientists and engineers, as in principle it can increase, by significant factors, the number of cycles that can be delivered to applications. However, new adaptive application structures and dynamic runtime system mechanisms are required if we are to operate effectively in grid environments. To explore some of these issues in a practical setting, the authors are developing an experimental framework, called Cactus, that incorporates both adaptive application structures for dealing with changing resource characteristics and adaptive resource selection mechanisms that allow applications to change their resource allocations (e.g., via migration) when performance falls outside specified limits. The authors describe the adaptive resource selection mechanisms and describe how they are used to achieve automatic application migration to "better" resources following performance degradation. The results provide insights into the architectural structures required to support adaptive resource selection. In addition, the authors suggest that the Cactus Worm affords many opportunities for grid computing. C1 Univ Chicago, Dept Comp Sci, Chicago, IL 60657 USA. Max Planck Inst Gravitat Phys, Potsdam, Germany. Argonne Natl Lab, Argonne, IL 60439 USA. Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Angulo, D (reprint author), Univ Chicago, Dept Comp Sci, 1100 E 58th St, Chicago, IL 60657 USA. EM dangulo@cs.uchicago.edu NR 32 TC 42 Z9 43 U1 0 U2 1 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 2001 VL 15 IS 4 BP 345 EP 358 DI 10.1177/109434200101500402 PG 14 WC Computer Science, Hardware & Architecture; Computer Science, Interdisciplinary Applications; Computer Science, Theory & Methods SC Computer Science GA 493NB UT WOS:000172228600002 ER PT J AU Ripeanu, M Iamnitchi, A Foster, I AF Ripeanu, M Iamnitchi, A Foster, I TI Performance predictions for a numerical relativity package in grid environments SO INTERNATIONAL JOURNAL OF HIGH PERFORMANCE COMPUTING APPLICATIONS LA English DT Article AB The Cactus software package is representative for a class of scientific applications that are tightly coupled, have regular space decompositions, and involve huge memory and processor time requirements. Cactus has proved to be a valuable tool for astrophysicists, who first initiated its development. However, today's fastest supercomputers are not powerful enough to perform realistic large-scale astrophysics simulations with Cactus. Instead, astrophysicists must turn to innovative resource environments-in particular, computational grids-to satisfy this need for computational power. This paper addresses issues related to the execution of applications such as Cactus in grid environments. The authors focus on two types of grids: a set of geographically distributed supercomputers and a collection of one million Internet-connected workstations. The authors study the application performance on traditional systems, validate the theoretical results against experimental data, and predict performance in the two new environments. C1 Univ Chicago, Dept Comp Sci, Chicago, IL 60657 USA. Argonne Natl Lab, Argonne, IL 60439 USA. RP Iamnitchi, A (reprint author), Univ Chicago, Dept Comp Sci, 1100 E 58th St, Chicago, IL 60657 USA. NR 15 TC 1 Z9 1 U1 0 U2 0 PU SAGE PUBLICATIONS INC PI THOUSAND OAKS PA 2455 TELLER RD, THOUSAND OAKS, CA 91320 USA SN 1094-3420 J9 INT J HIGH PERFORM C JI Int. J. High Perform. Comput. Appl. PD WIN PY 2001 VL 15 IS 4 BP 375 EP 387 DI 10.1177/109434200101500404 PG 13 WC Computer Science, Hardware & Architecture; Computer Science, Interdisciplinary Applications; Computer Science, Theory & Methods SC Computer Science GA 493NB UT WOS:000172228600004 ER PT J AU Wang, YT Hermann, AM Bhattacharya, RN Blaugher, RD AF Wang, YT Hermann, AM Bhattacharya, RN Blaugher, RD TI The study of critical current density of superconducting thallium oxide films from spray-deposited precursors SO INTERNATIONAL JOURNAL OF HYDROGEN ENERGY LA English DT Article; Proceedings Paper CT 4th International Symposium on New Materials, Renewable Energy and Environment CY AUG 27-31, 2000 CL CANCUN, MEXICO AB Spray deposition is a promising and economic approach for fabricating high-temperature superconducting films for the Tl-oxide superconductors. The Tl-oxides provide the potential for operation at 77 K in practical magnetic fields of 3-5 T, which has been demonstrated by measurements on the irreversibility behavior of the Tl-1223 single layer compound with Bi and Sr substitution. In this report, we present the preparation and characterization of Tl0.78Bi0.22Sr1.6Ba0.4Ca2Cu3O9 superconducting films fabricated from spray-deposited Tl-free, Ag-containing and Cu-rich precursors and reacted with thallium vapor using a two-step crucible process at 650 degreesC/815 degreesC in flowing argon for only 10/10 min. An epitaxial superconducting film was synthesized successfully and critical cur-rent densities of 8 x 10(5) A/cm(2) at 77 K in zero-field were obtained with excellent in-field performance. (C) 2001 Published by Elsevier Science Ltd on behalf of the International Association for Hydrogen Energy. C1 Univ Colorado, Dept Phys, Boulder, CO 80309 USA. Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Hermann, AM (reprint author), Univ Colorado, Dept Phys, Campus Box 309, Boulder, CO 80309 USA. NR 7 TC 6 Z9 6 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0360-3199 J9 INT J HYDROGEN ENERG JI Int. J. Hydrog. Energy PD DEC PY 2001 VL 26 IS 12 BP 1289 EP 1293 DI 10.1016/S0360-3199(01)00062-3 PG 5 WC Chemistry, Physical; Electrochemistry; Energy & Fuels SC Chemistry; Electrochemistry; Energy & Fuels GA 497XB UT WOS:000172479800006 ER PT J AU Chhabildas, LC Thornhill, TF Reinhart, WD Kipp, ME Reedal, DR Wilson, LT Grady, DE AF Chhabildas, LC Thornhill, TF Reinhart, WD Kipp, ME Reedal, DR Wilson, LT Grady, DE TI Fracture resistant properties of AerMet steels SO INTERNATIONAL JOURNAL OF IMPACT ENGINEERING LA English DT Article; Proceedings Paper CT Symposium on Hypervelocity Impact CY NOV 06-10, 2000 CL GALVESTON, TEXAS ID FRAGMENTATION AB The purpose of this study is to report well-controlled experiments conducted to determine the fracture resistant properties of AerMet(R) 100 steels. One of the objectives of this study is to determine the influence of fracture toughness properties on the fracture and fragmentation process. Both sphere impact tests and cylinder expansion test geometry were used to determine the dynamic fracture resistant coefficients. These experiments were conducted at strain rates of similar to 14 x 10(3)/s for the cylinder expansion tests; the strain rates for the sphere impact tests varied over 50 to 100 x 10(3)/s. Fracture resistant coefficients of 60 MPa rootm and 20 MPa rootm are obtained from the cylinder test and the sphere impact test, respectively. These measurements do not agree with the static fracture toughness values reported in the literature. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Sandia Natl Labs, Dept 1610, Albuquerque, NM 87185 USA. Ktech Corp Inc, Albuquerque, NM 87106 USA. USN, Ctr Surface Warfare, Dahlgren Div, Dahlgren, VA 22448 USA. Appl Res Associates, Albuquerque, NM 87110 USA. RP Chhabildas, LC (reprint author), Sandia Natl Labs, Dept 1610, POB 5800, Albuquerque, NM 87185 USA. NR 16 TC 8 Z9 8 U1 1 U2 5 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0734-743X J9 INT J IMPACT ENG JI Int. J. Impact Eng. PD DEC PY 2001 VL 26 IS 1-10 BP 77 EP 91 DI 10.1016/S0734-743X(01)00068-9 PG 15 WC Engineering, Mechanical; Mechanics SC Engineering; Mechanics GA 510ZN UT WOS:000173237600010 ER PT J AU Furnish, MD Lawrence, RJ Hall, CA Asay, JR Barker, DL Mize, GA Marsh, EA Bernard, MA AF Furnish, MD Lawrence, RJ Hall, CA Asay, JR Barker, DL Mize, GA Marsh, EA Bernard, MA TI Radiation-driven shock and debris propagation down a partitioned pipe SO INTERNATIONAL JOURNAL OF IMPACT ENGINEERING LA English DT Article; Proceedings Paper CT Symposium on Hypervelocity Impact CY NOV 06-10, 2000 CL GALVESTON, TX DE Z-pinch; debris; debris propagation; ALEGRA; VISAR; melting; vaporization AB Two experiments have been performed to measure the effects of pulsed radiation loads on the front of small tubular structures, using as an energy source the X-ray fluence produced by a Z-pinch at the Sandia National Laboratories Z Facility. The project had two major goals: to establish the feasibility of using the Z machine to study the phenomenology associated with debris generation and propagation down tubular structures with partitions; and to use the resultant experimental data to validate numerical hydrocodes (shock physics codes) so that we have confidence in their use in analyzing these types of situations. Two tubular aluminum structures (5 and 10 cm long and 1 cm inside diameter) were prepared, with aluminum partitions located at the front, halfway down the pipe, and at the rear. Interferometry (VISARs) provided multiple velocity histories for all of the partitions. In both experiments, the first barrier, which was exposed directly to the x-ray fluence, was launched into the pipe at a velocity of similar to 2 km/s, accelerating to give a mean velocity of similar to 2.6 km/s. Loss of plate integrity is inferred from the dispersed launch of the second partition at similar to 1 km/s. Wall shocks propagating at 4.5 km/s were inferred. Post-test metallography showed evidence of melting and partial vaporization of the plates, and turbulent mixing with material from the walls. Calculations qualitatively agree with the observed results, but slightly overpredict debris velocity, possibly due to overestimates of total energy fluence. An application for this work is the study of techniques for line-of-sight shock and debris mitigation on high-power pulsed power facilities such as Z and its follow-on machines. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Bechtel Nevada Corp, Las Vegas, NV 89193 USA. Ktech Corp Inc, Albuquerque, NM 87106 USA. RP Furnish, MD (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 6 TC 2 Z9 2 U1 1 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0734-743X J9 INT J IMPACT ENG JI Int. J. Impact Eng. PD DEC PY 2001 VL 26 IS 1-10 BP 189 EP 200 DI 10.1016/S0734-743X(01)00082-3 PG 12 WC Engineering, Mechanical; Mechanics SC Engineering; Mechanics GA 510ZN UT WOS:000173237600019 ER PT J AU Gerassimenko, M AF Gerassimenko, M TI Modeling of measured target pressure profiles in three hypervelocity impact experiments SO INTERNATIONAL JOURNAL OF IMPACT ENGINEERING LA English DT Article; Proceedings Paper CT Symposium on Hypervelocity Impact CY NOV 06-10, 2000 CL GALVESTON, TX DE hypervelocity impacts; pressure measurements; pressure modeling AB A 24 g aluminum sphere was shot at a sparse array of cylinders with nominal initial projectile velocity of 4 and 5 km/s. Pressure profiles were measured with cased carbon resistor gages at two locations in a projectile impacted water filled cylinder and two of its neighbors on three shots. The pressure maxima were in the 1-13 kbars range. The experiments are modeled with the ALE3D code and several techniques are used to concentrate zoning at places of interest, There is excellent agreement between the measured and calculated pressure profiles for two shots and good agreement for the third. Comparison of the calculated pressure profiles with those from more refined calculations for two shots suggest that we are near convergence with respect to zone size. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Gerassimenko, M (reprint author), Lawrence Livermore Natl Lab, 7000 East Ave, Livermore, CA 94550 USA. NR 3 TC 1 Z9 1 U1 1 U2 2 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0734-743X J9 INT J IMPACT ENG JI Int. J. Impact Eng. PD DEC PY 2001 VL 26 IS 1-10 BP 221 EP 230 DI 10.1016/S0734-743X(01)00089-6 PG 10 WC Engineering, Mechanical; Mechanics SC Engineering; Mechanics GA 510ZN UT WOS:000173237600022 ER PT J AU Hall, CA Knudson, MD Asay, JR Lemke, R Oliver, B AF Hall, CA Knudson, MD Asay, JR Lemke, R Oliver, B TI High velocity flyer plate launch capability on the Sandia Z Accelerator SO INTERNATIONAL JOURNAL OF IMPACT ENGINEERING LA English DT Article; Proceedings Paper CT Symposium on Hypervelocity Impact CY NOV 06-10, 2000 CL GALVESTON, TEXAS DE equation of state; hypervelocity launch; plates AB A method has been developed for launching plates useful for equation of state (EOS) studies to high velocities using fast pulsed power on the Sandia National Laboratories Z Accelerator. The technique employs magnetic pressure developed in an insulating gap between the anode and cathode of the machine to provide smoothly increasing, quasi - isentropic loading to plates of 9 - 12 mm in diameter and hundreds of microns thickness. Successful launches of titanium to similar to 12km/s, aluminum to similar to 13km/s, and copper to similar to 10km/s have been demonstrated. The plates were monitored through the entire launch process with both conventional and spatially resolved velocity interferometry to obtain acceleration histories and impact profiles. Impacts of the flyers into aluminum wedges were also performed to experimentally estimate final plate thickness. Initial indications are that the plates are intact, slightly bowed, and at essentially ambient state. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Sandia Natl Labs, Shock Phys Applicat Dept, Albuquerque, NM 87185 USA. Mission Res Corp, Albuquerque, NM 87110 USA. RP Hall, CA (reprint author), Sandia Natl Labs, Shock Phys Applicat Dept, POB 5800, Albuquerque, NM 87185 USA. NR 13 TC 7 Z9 11 U1 0 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0734-743X J9 INT J IMPACT ENG JI Int. J. Impact Eng. PD DEC PY 2001 VL 26 IS 1-10 BP 275 EP 287 DI 10.1016/S0734-743X(01)00088-4 PG 13 WC Engineering, Mechanical; Mechanics SC Engineering; Mechanics GA 510ZN UT WOS:000173237600027 ER PT J AU Lomov, IN Hiltl, M Vorobiev, OY Glenn, LA AF Lomov, IN Hiltl, M Vorobiev, OY Glenn, LA TI Dynamic behavior of berea sandstone for dry and water-saturated conditions SO INTERNATIONAL JOURNAL OF IMPACT ENGINEERING LA English DT Article; Proceedings Paper CT Symposium on Hypervelocity Impact CY NOV 06-10, 2000 CL GALVESTON, TEXAS AB Wave profile measurements have been performed on dry and water-saturated Berea sandstone under shock compression loading conditions using a single-stage light gas-gun. The wave motion was monitored with a VISAR velocity interferometer. The impact velocities achieved in the experiment were in the range between 433 m/s and 1013 m/s. Significant differences were observed in the dynamic response of dry and water-saturated Berea sandstone. This work presents the experimental results as well as simulation results obtained using a phenomenological model of Berea sandstone. The model includes effects of compaction, plastic yielding and damage. In the model, the behavior of the water-saturated material was addressed with a modified effective stress model. The simulated wave profiles agree with the experimental data for both dry and water-saturated conditions. This validates the current model and provides a baseline for its further application. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Lomov, IN (reprint author), Lawrence Livermore Natl Lab, 7000 East Ave, Livermore, CA 94550 USA. NR 18 TC 8 Z9 8 U1 0 U2 5 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0734-743X J9 INT J IMPACT ENG JI Int. J. Impact Eng. PD DEC PY 2001 VL 26 IS 1-10 BP 465 EP 474 DI 10.1016/S0734-743X(01)00097-5 PG 10 WC Engineering, Mechanical; Mechanics SC Engineering; Mechanics GA 510ZN UT WOS:000173237600043 ER PT J AU Reinhart, WD Chhabildas, LC Carroll, DE Bergstresser, TK Thornhill, TF Winfree, NA AF Reinhart, WD Chhabildas, LC Carroll, DE Bergstresser, TK Thornhill, TF Winfree, NA TI Equation of state measurements of materials using a three-stage gun to impact velocities of 11 km/s SO INTERNATIONAL JOURNAL OF IMPACT ENGINEERING LA English DT Article; Proceedings Paper CT Symposium on Hypervelocity Impact CY NOV 06-10, 2000 CL GALVESTON, TEXAS ID HYPERVELOCITY AB Results of an experimental series performed utilizing a three-stage gun to obtain precise material property equation of state (EOS) data for a titanium alloy (Ti6-A1-4V) at extreme pressure states that are not currently attainable using conventional two-stage light-gas gun technology is reported herein. What is new is the technique being implemented for use at engagement velocities exceeding 11 km/s. Shock-velocity in the target is being determined using 100 gm diameter fiber-optic pins and measuring shock transit times over a known distance between two parallel planes. These fiber-optic pins also indicate that the flyer-plate bow and tilt is comparable to two-stage light-gas gun technology. The thermodynamic state of the flyer plate prior to impact has also been determined both experimentally and calculationally. In particular, the temperature, and hence the density of the flyer-plate is also well known prior to impact. Results of these studies indicate that accurate Hugoniot information can be obtained using the three-stage light gas gun. This new test-methodology has extended the EOS of Ti6-A1-4V titanium alloy to stresses up to approximately 250 GPa. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Ktech Corp Inc, Albuquerque, NM 87109 USA. Appl Res Associates, Albuquerque, NM 87110 USA. RP Reinhart, WD (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 28 TC 16 Z9 22 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0734-743X J9 INT J IMPACT ENG JI Int. J. Impact Eng. PD DEC PY 2001 VL 26 IS 1-10 BP 625 EP 637 DI 10.1016/S0734-743X(01)00124-5 PG 13 WC Engineering, Mechanical; Mechanics SC Engineering; Mechanics GA 510ZN UT WOS:000173237600057 ER PT J AU Wilbeck, JS Herwig, SB Kilpatrick, JM Faux, DR Weir, RJ Hertel, ES Dutta, MK AF Wilbeck, JS Herwig, SB Kilpatrick, JM Faux, DR Weir, RJ Hertel, ES Dutta, MK TI Hypervelocity impact of spaced plates by a mock kill vehicle SO INTERNATIONAL JOURNAL OF IMPACT ENGINEERING LA English DT Article; Proceedings Paper CT Symposium on Hypervelocity Impact CY NOV 06-10, 2000 CL GALVESTON, TEXAS AB In support of the National Missile Defense (NMD) program, a series of Light Gas Gun (LGG) lethality tests were conducted at the Arnold Engineering Development Center (AEDC). A new projectile was designed for this test series that would be representative of aspects of a generic NMD system kill vehicle. A series of projectile development tests were performed during the design phase of the projectile. This paper reports the results from the second development shot, in which the projectile impacted normally against two thin aluminum target plates, spaced approximately 5.5 diameters apart. Results reported include the documentation of the damage to the first and second plates, the debris generated behind the first plate, and correlation of these with analytical and numerical predictions. Hydrocodes used for analyses included ALE3D, run by the Lawrence Livermore National Laboratory, and CTH, run by the Sandia National Laboratory. The purpose of the hydrocode analyses was to help in assessing the ability of these codes to predict the debris formation process and the target damage. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 ITT Ind Inc, Adv Engn & Sci Div, Huntsville, AL 35802 USA. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. USA, Space Missile Def Command, Huntsville, AL 35807 USA. RP Wilbeck, JS (reprint author), ITT Ind Inc, Adv Engn & Sci Div, Huntsville, AL 35802 USA. NR 3 TC 0 Z9 0 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0734-743X J9 INT J IMPACT ENG JI Int. J. Impact Eng. PD DEC PY 2001 VL 26 IS 1-10 BP 853 EP 864 DI 10.1016/S0734-743X(01)00139-7 PG 12 WC Engineering, Mechanical; Mechanics SC Engineering; Mechanics GA 510ZN UT WOS:000173237600076 ER PT J AU Ahluwalia, DV Kirchbach, M AF Ahluwalia, DV Kirchbach, M TI Primordial spacetime foam as an origin of cosmological matter-antimatter asymmetry SO INTERNATIONAL JOURNAL OF MODERN PHYSICS D LA English DT Article ID QUANTUM-GRAVITY; UNCERTAINTY PRINCIPLE; DIRAC-EQUATION; TIME-FOAM; NEUTRINO; INTERFEROMETERS; VIOLATION AB The possibility is raised that the observed cosmological matter-antimatter asymmetry may reside in asymmetric spacetime fluctuations and their interplay with the Stuckelberg-Feynman interpretation of antimatter. The presented thesis also suggests that the effect of spacetime fluctuations is to diminish the Fine structure constant in the past. Recent studies of the QSO absorption lines provide a 4.1 standard deviation support for this prediction. Our considerations suggest that in the presence of spacetime fluctuations, the principle of local gauge invariance, and the related notion of parallel transport, must undergo fundamental changes. C1 Univ Autonoma Zacatecas, Fac Fis, ISGBG, Zacatecas 98062, Mexico. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Ahluwalia, DV (reprint author), Univ Autonoma Zacatecas, Fac Fis, ISGBG, Ap Postal C-600, Zacatecas 98062, Mexico. NR 38 TC 16 Z9 16 U1 0 U2 1 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA JOURNAL DEPT PO BOX 128 FARRER ROAD, SINGAPORE 912805, SINGAPORE SN 0218-2718 J9 INT J MOD PHYS D JI Int. J. Mod. Phys. D PD DEC PY 2001 VL 10 IS 6 BP 811 EP 823 DI 10.1142/S0218271801001608 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 514LA UT WOS:000173439600009 ER PT J AU Stephens, GJ Hu, BL AF Stephens, GJ Hu, BL TI Notes on black hole phase transitions SO INTERNATIONAL JOURNAL OF THEORETICAL PHYSICS LA English DT Article ID FINITE TEMPERATURE; QUANTUM STATISTICS; SONIC ANALOG; THERMODYNAMICS; EVAPORATION; SPACETIME; ENTROPY AB In these notes we present a summary of existing ideas about phase transitions of black hole spacetimes in semiclassical gravity and offer some thoughts on three possible scenarios or mechanisms by which these transitions could take place. We begin with a review of the thermodynamics of a black hole system and emphasize that the phase transition is driven by the large entropy of the black hole horizon. Our first theme is illustrated by a quantum atomic black hole system, generalizing to finite-temperature a model originally offered by Bekenstein. In this equilibrium atomic model, the black hole phase transition is realized as the abrupt excitation of a high energy state, suggesting analogies with the study of two-level atoms. Our second theme argues. that the black hole system shares similarities with the defect-mediated Kosterlitz-Thouless transition in condensed matter. These similarities suggest that the black hole phase transition may be more fully understood by focusing upon the dynamics of black holes and white holes, the spacetime analogy of vortex and antivortex topological defects. Finally, we compare the black hole phase transition to another transition driven by an (exponentially) increasing density of states, the Hagedorn transition first found in hadron physics in the context of dual models or the old string theory. In modern string theory the Hagedorn transition is linked by the Maldacena conjecture to the Hawking-Page black hole phase transition in Anti-de Sitter (AdS) space, as observed by Witten. Thus, the dynamics of the Hagedorn transition may yield insight into the dynamics of the black hole phase transition. We argue that characteristics of the Hagedorn transition are already contained within the dynamics of classical string systems. Our third theme points to carrying out a full nonperturbative and nonequilibrium analysis of the large N behavior of classical SU(N) gauge theories to understand its Hagadorn transition. By invoking the Maldacena conjecture we can then gain valuable insight into black hole phase transitions in AdS space. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Maryland, Dept Phys, College Pk, MD 20742 USA. RP Stephens, GJ (reprint author), Los Alamos Natl Lab, Theoret Astrophys T-6 MS-B288, Los Alamos, NM 87545 USA. NR 53 TC 14 Z9 14 U1 0 U2 1 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0020-7748 J9 INT J THEOR PHYS JI Int. J. Theor. Phys. PD DEC PY 2001 VL 40 IS 12 BP 2183 EP 2200 DI 10.1023/A:1012930019453 PG 18 WC Physics, Multidisciplinary SC Physics GA 505BZ UT WOS:000172892600004 ER PT J AU Anderson, PR Eaker, W Habib, S Molina-Paris, C Mottola, E AF Anderson, PR Eaker, W Habib, S Molina-Paris, C Mottola, E TI Attractor states and quantum instabilities in de Sitter space SO INTERNATIONAL JOURNAL OF THEORETICAL PHYSICS LA English DT Article ID ENERGY-MOMENTUM TENSOR; INFLATIONARY UNIVERSE SCENARIO; ADIABATIC REGULARIZATION; SCALAR FIELDS; DESITTER-SPACE; VACUUM STATES; STRESS-ENERGY; RENORMALIZATION AB The asymptotic behavior of the energy-momentum tensor for a free quantized scalar field with mass m and curvature coupling in de Sitter space is investigated. It is shown that for an arbitrary, homogeneous, and isotropic, fourth-order adiabatic state for which the two-point function is infrared finite, approaches the Bunch-Davies de Sitter invariant value at late times if m(2) + xi R > 0. In the case m = xi = 0, the energy-momentum tensor approaches the de Sitter invariant Allen-Folacci value for such a state. For m(2) + R = 0 but m and not separately zero, it is shown that at late times grows linearly in terms of cosmic time leading to an instability of de Sitter space. The asymptotic behavior is again independent of the state of the field. For m(2) + R < 0, it is shown that, for most values of m and xi, grows exponentially in terms of cosmic time at late times in a state dependent manner. C1 Wake Forest Univ, Dept Phys, Winston Salem, NC 27109 USA. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM USA. CSIC, INTA, Ctr Astrobiol, Madrid 28850, Spain. RP Anderson, PR (reprint author), Wake Forest Univ, Dept Phys, Winston Salem, NC 27109 USA. NR 30 TC 4 Z9 4 U1 0 U2 0 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0020-7748 J9 INT J THEOR PHYS JI Int. J. Theor. Phys. PD DEC PY 2001 VL 40 IS 12 BP 2217 EP 2229 DI 10.1023/A:1012934204432 PG 13 WC Physics, Multidisciplinary SC Physics GA 505BZ UT WOS:000172892600006 ER PT J AU Molina-Paris, C Anderson, PR Ramsey, SA AF Molina-Paris, C Anderson, PR Ramsey, SA TI Interacting field theories in Robertson-Walker spacetimes: Analytic approximations SO INTERNATIONAL JOURNAL OF THEORETICAL PHYSICS LA English DT Article ID ENERGY-MOMENTUM TENSOR; ADIABATIC REGULARIZATION; CURVED SPACETIME; QUANTUM-FIELDS; SCALAR FIELD; EVOLUTION EQUATION; PARTICLE HORIZONS; EXPECTATION VALUE; POINT-SEPARATION; EARLY UNIVERSE AB The renormalization of a scalar field theory with a quartic self-coupling via adiabatic regularization in a Robertson-Walker spacetime is discussed. The adiabatic counterterms are presented in a way that is most conducive to numerical computations. A variation of the adiabatic regularization method is presented which leads to analytic approximations for the energy-momentum tensor of the quantum field and the quantum contribution to the effective mass of the mean field. Conservation of the energy-momentum tensor for the field is discussed and it is shown that the part of the energy-momentum tensor which depends only on the mean field is not conserved but the full renormalized energy-momentum tensor is conserved, as expected and required by the semiclassical Einstein's equation. It is also shown that if the analytic approximations are used the resulting approximate energy-momentum tensor is conserved. This allows a self-consistent backreaction calculation to be performed using the analytic approximations. The usefulness of the approximation, is discussed. C1 Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. CSIC, INTA, Ctr Astrobiol, Madrid, Spain. Wake Forest Univ, Dept Phys, Winston Salem, NC 27109 USA. Univ Washington, Genome Ctr, Seattle, WA 98195 USA. RP Molina-Paris, C (reprint author), Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. NR 45 TC 2 Z9 2 U1 0 U2 0 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0020-7748 J9 INT J THEOR PHYS JI Int. J. Theor. Phys. PD DEC PY 2001 VL 40 IS 12 BP 2231 EP 2258 DI 10.1023/A:1012938321270 PG 28 WC Physics, Multidisciplinary SC Physics GA 505BZ UT WOS:000172892600007 ER PT J AU Proffen, T Neder, RB Billinge, SJL AF Proffen, T Neder, RB Billinge, SJL TI Teaching diffraction using computer simulations over the Internet SO JOURNAL OF APPLIED CRYSTALLOGRAPHY LA English DT Article ID SCATTERING AB Computer simulations are a versatile tool to enhance the teaching of diffraction physics and related crystallographic topics to students of chemistry, materials science, physics and crystallography. Interactive computer simulations are presented, which have been added to a World Wide Web (WWW) based tutorial. A simple WWW interface is used to choose appropriate values for selected simulation parameters. The resulting structure and diffraction pattern are then plotted on the screen. Simulated structures range from a single atom to complex disordered or modulated structures. The simple interface requires no special computing knowledge and allows students to explore systematically the relationship between a real-space structure and the corresponding diffraction pattern. The large function set of the underlying simulation program (DISCUS) makes it easy to tailor the tutorial to a given syllabus by modifying or extending the current interactive examples. C1 Los Alamos Natl Lab, LANSCE 12, Los Alamos, NM 87545 USA. Univ Wurzburg, Inst Mineral, D-97074 Wurzburg, Germany. Michigan State Univ, Dept Phys & Astron, E Lansing, MI 48824 USA. Michigan State Univ, Ctr Fundamental Mat Res, E Lansing, MI 48824 USA. RP Proffen, T (reprint author), Los Alamos Natl Lab, LANSCE 12, MS H805, Los Alamos, NM 87545 USA. RI Lujan Center, LANL/G-4896-2012; Neder, Reinhard/D-9877-2013; Proffen, Thomas/B-3585-2009 OI Neder, Reinhard/0000-0003-2592-2207; Proffen, Thomas/0000-0002-1408-6031 NR 8 TC 3 Z9 3 U1 0 U2 6 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 PY 2001 VL 34 BP 767 EP 770 DI 10.1107/S0021889801013656 PN 6 PG 4 WC Chemistry, Multidisciplinary; Crystallography SC Chemistry; Crystallography GA 493QE UT WOS:000172233900014 ER PT J AU Clements, BE Mas, EM AF Clements, BE Mas, EM TI Dynamic mechanical behavior of filled polymers. I. Theoretical developments SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID ELASTIC PROPERTIES; COMPOSITES; INCLUSIONS; SOFTWARE; MATRIX AB A constitutive theory is developed for modeling the mechanical response of dynamically loaded filled-polymer composites. The basis for this work is Mori and Tanaka's effective medium theory. Expressions derived by Weng and co-workers are used for the elastic stiffness tensor of the composite. The filler is a low volume concentration of randomly positioned elastic ellipsoidal particles. Random and aligned orientations of the ellipsoids are considered. The viscoelastic stress-strain behavior of the polymer matrix is modeled using the Boltzmann superposition principle with a Prony series representation for the stress relaxation functions. We argue that for rubbery polymers it is reasonable to express the composite stress relaxation functions as series expansions about the ratio of the polymer shear relaxation function to its bulk modulus. The smallness of this ratio allows accurate results to be obtained when truncating the expansion at first order. Inverse Laplace transformations required by the theory can then be done analytically. The result of these manipulations is again a Prony series for the stress relaxation functions of the composite, but with series coefficients that are now functions of the filler concentration, ellipsoidal aspect ratio, and moduli. In the limit of low filler concentration the theory reduces to known results derived in classical suspension theory. (C) 2001 American Institute of Physics. C1 Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Clements, BE (reprint author), Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. NR 30 TC 17 Z9 17 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 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD DEC 1 PY 2001 VL 90 IS 11 BP 5522 EP 5534 DI 10.1063/1.1412843 PG 13 WC Physics, Applied SC Physics GA 491UV UT WOS:000172129200011 ER PT J AU Mas, EM Clements, BE AF Mas, EM Clements, BE TI Dynamic mechanical behavior of filled polymers. II. Applications SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID VISCOELASTIC BEHAVIOR; ELASTIC PROPERTIES; COMPOSITES; INCLUSIONS; MATRIX; RATIO AB A filled-polymer composite theory, based on effective medium theory, has been developed that allows the dynamic mechanical behavior to be modeled. The stress-strain behavior of the composite is derived using Schapery's nonequilibrium thermodynamic basis for generalizing Boltzmann's superposition principle, in conjunction with a Prony series representation for the stress relaxation moduli. Schapery's theory allows nonlinear viscoelastic effects to be included into the mechanical response. The coefficients of the Prony series are functions of the filler's bulk modulus, concentration, and shape. The theory is applicable to rubbery polymers and is shown to be accurate for filler concentrations up to approximately 30%. Higher concentrations can be modeled by introducing a phenomenological filler-filler correlation parameter. Effects due to heating and varying strain rate are easily accounted for in this approach. To demonstrate the utility and validity of the theory we compare its predictions to several dynamic experiments on filled-polymer composites. A discussion is provided on implementing the theory in three-dimensional finite element simulations. (C) 2001 American Institute of Physics. C1 Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Clements, BE (reprint author), Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. NR 29 TC 9 Z9 9 U1 1 U2 9 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 2001 VL 90 IS 11 BP 5535 EP 5541 DI 10.1063/1.1412844 PG 7 WC Physics, Applied SC Physics GA 491UV UT WOS:000172129200012 ER PT J AU Myers, SM Wright, AF AF Myers, SM Wright, AF TI Theoretical description of H behavior in GaN p-n junctions SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID MG-DOPED GAN; CHEMICAL-VAPOR-DEPOSITION; ELECTRON-DIFFUSION LENGTH; BEAM IRRADIATION; HYDROGEN; ACTIVATION; TRANSPORT; ACCEPTORS; NITRIDES; GALLIUM AB The diffusion and reactions of hydrogen in GaN are described by applying differential equations for the concentration profiles of H species, charged dopants, and carriers with simultaneous solution of Poisson's equation. This approach dispenses with the simplifying assumptions of local equilibrium among states and local charge neutrality that were employed previously by us to treat high-temperature H behavior in uniform layers. The result is a more general modeling capability which encompasses nonequilibrium conditions and space-charge effects such as are encountered in devices. Density-functional theory, previously used by us to treat equilibrium H energies, is employed herein to examine activation barriers and wave-function overlaps affecting the rates of relevant H and carrier reactions, thereby guiding the selection of mechanisms to be included and influencing the evaluation of some rate parameters. The model is applied to H-containing p-n junctions, with detailed consideration of the reversible, metastable electrical activation of H-passivated Mg acceptors that has been observed experimentally under forward bias. The calculations point to interstitial H-2 as the state of the H resulting from such activation, and this conclusion is supported by good agreement between the predicted and observed onset temperatures for repassivation under open-circuit annealing. In modeling the more complex activation process, experimentally observed qualitative features are reproduced by choosing relative carrier-capture cross sections in accord with ab initio theoretical considerations. In other model calculations, H is shown to be expelled from the carrier-depleted zone of p-n junctions, causing H redistribution under reverse bias. (C) 2001 American Institute of Physics. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Myers, SM (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 24 TC 33 Z9 34 U1 1 U2 11 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 2001 VL 90 IS 11 BP 5612 EP 5622 DI 10.1063/1.1413950 PG 11 WC Physics, Applied SC Physics GA 491UV UT WOS:000172129200024 ER PT J AU Samoilova, TB Astafiev, KF Rivkin, T Ginley, DS AF Samoilova, TB Astafiev, KF Rivkin, T Ginley, DS TI Frequency conversion in coplanar waveguide based on BaxSr1-xTiO3 film SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID THIN-FILMS; SRTIO3 AB We report on both a model and experimental verification of the high frequency nonlinearity for coplanar waveguides (CPW) composed of a dielectric substrate coated with nonlinear dielectric Ba0.4Sr0.6TiO3 films. For the CPW with a propagating microwave signal (f(0)approximate to 30 GHz), modulation of Ba0.4Sr0.6TiO3 film dielectric constant by a high frequency (f(p)approximate to 20 MHz) pump signal results in the generation of sidebands with frequency (f(0)+/- Nf(p)). Experimental and simulated spectra of CPW output signals are presented as a function of the direct current bias voltage, pump voltage amplitude, CPW length, and CPW nonlinearity. (C) 2001 American Institute of Physics. C1 State Electrotech Univ, St Petersburg 197376, Russia. Ecole Polytech Fed Lausanne, Swiss Fed Inst Technol, Dept Mat, Ceram Lab, CH-1015 Lausanne, Switzerland. Natl Renewable Energy Lab, Golden, CO 80401 USA. RP State Electrotech Univ, Prof Popov St 5, St Petersburg 197376, Russia. EM konstantin.astafiev@epfl.ch NR 16 TC 8 Z9 8 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 0021-8979 EI 1089-7550 J9 J APPL PHYS JI J. Appl. Phys. PD DEC 1 PY 2001 VL 90 IS 11 BP 5703 EP 5707 DI 10.1063/1.1408266 PG 5 WC Physics, Applied SC Physics GA 491UV UT WOS:000172129200040 ER PT J AU Zhu, JS Jager, K Black, T Zarka, K Koksharova, O Wolk, CP AF Zhu, JS Jager, K Black, T Zarka, K Koksharova, O Wolk, CP TI HcwA, an autolysin, is required for heterocyst maturation in Anabaena sp strain PCC 7120 SO JOURNAL OF BACTERIOLOGY LA English DT Article ID CYANOBACTERIUM ANABAENA; CLONING SITES; CELL-WALLS; PCC-7120; GENE; VECTORS; DNA; SENSITIVITY; EXPRESSION; PLASMID AB In many filamentous cyanobacteria, vegetative cells can differentiate into heterocysts, cells that are specialized for aerobic fixation of N-2. Synthesis of the heterocyst envelope polysaccharide is dependent on the gene hepA in Anabaena sp. strain PCC 7120. In search of genes that are involved in the regulation of hepA, we transposon mutagenized strain DR1069, which bears a chromosomal hepA::luxAB fusion. One resulting mutant, designated HNL3, grows normally in medium with nitrate and shows poor induction of hepA in response to nitrogen deprivation. In HNL3, transposon Tn5-1058 is inserted within gene hcwA, a constitutively expressed open reading frame whose predicted product resembles N-acetylmuramoyl-L-alanine amidases. Reconstruction of the mutation confirmed that the mutant phenotype resulted from the insertion of the transposon. The induction of hepA in HNL3 is partially restored upon recombination of HNL3 with plasmid-borne, wild-type hcwA. Moreover, HcwA expressed in Escherichia coli exhibits wall-lytic activity. These results suggest that the degradation, or possibly reconstruction, of the cell peptidoglycan layer is a prerequisite for heterocyst maturation. 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. NR 39 TC 35 Z9 37 U1 1 U2 1 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 2001 VL 183 IS 23 BP 6841 EP 6851 DI 10.1128/JB.183.23.6841-6851.2001 PG 11 WC Microbiology SC Microbiology GA 492FW UT WOS:000172158600016 PM 11698373 ER PT J AU Schut, GJ Zhou, JZ Adams, MWW AF Schut, GJ Zhou, JZ Adams, MWW TI DNA microarray analysis of the hyperthermophilic archaeon Pyrococcus furiosus: Evidence for a new type of sulfur-reducing enzyme complex SO JOURNAL OF BACTERIOLOGY LA English DT Article ID PYRUVATE FERREDOXIN OXIDOREDUCTASE; GENE-EXPRESSION PATTERNS; SMALL NUCLEOLAR RNAS; ESCHERICHIA-COLI; ORNITHINE CARBAMOYLTRANSFERASE; BIOCHEMICAL-CHARACTERIZATION; CRYSTAL-STRUCTURE; HYDROGENASE; GENOME; METABOLISM AB DNA microarrays were constructed by using 271 open reading frame (ORFs) from the genome of the archaeon Pyrococcus furiosus. They were used to investigate the effects of elemental sulfur (S degrees) on the levels of gene expression in cells grown at 95 degreesC with maltose as the carbon source. The ORFs included those that are proposed to encode proteins mainly involved in the pathways of sugar and peptide catabolism, in the metabolism of metals, and in the biosynthesis of various cofactors, amino acids, and nucleotides. The expression of 21 ORFs decreased by more than fivefold when cells were grown with S degrees and, of these, 18 encode subunits associated with three different hydrogenase systems. The remaining three ORFs encode homologs of ornithine carbamoyltransferase and HypF, both of which appear to be involved in hydrogenase biosynthesis, as well as a conserved hypothetical protein. The expression of two previously uncharacterized ORFs increased by more than 25-fold when cells were grown with S degrees. Their products, termed SipA and SipB (for sulfur-induced proteins), are proposed to be part of a novel S'-reducing, membrane-associated, iron-sulfur cluster-containing complex. Two other previously uncharacterized ORFs encoding a putative flavoprotein and a second FeS protein were upregulated more than sixfold in S degrees -grown cells, and these are also thought be involved in S degrees reduction. Four ORFs that encode homologs of proteins involved in amino acid metabolism were similarly upregulated in S degrees -grown cells, a finding consistent with the fact that growth on peptides is a S'-dependent process. An ORF encoding a homolog of the eukaryotic rRNA processing protein, fibrillarin, was also upregulated sixfold in the presence of S degrees, although the reason for this is as yet unknown. Of the 20 S degrees -independent ORFs that are the most highly expressed (at more than 20 times the detection limit), 12 of them represent enzymes purified from P. furiosus, but none of the products of the 34 S degrees -independent ORFs that are not expressed above the detection limit have been characterized. These results represent the first derived from the application of DNA microarrays to either an archaeon or a hyperthermophile. C1 Univ Georgia, Dept Biochem & Mol Biol, Athens, GA 30602 USA. Univ Georgia, Ctr Metalloenzyme Studies, Athens, GA 30602 USA. Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. RP Adams, MWW (reprint author), Univ Georgia, Dept Biochem & Mol Biol, Life Sci Bldg, Athens, GA 30602 USA. FU NIGMS NIH HHS [GM 60329, R01 GM060329] NR 79 TC 65 Z9 67 U1 2 U2 2 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 2001 VL 183 IS 24 BP 7027 EP 7036 DI 10.1128/JB.183.24.7027-7036.2001 PG 10 WC Microbiology SC Microbiology GA 496HQ UT WOS:000172390500007 PM 11717259 ER PT J AU Radziszewski, JG Gil, M Gorski, A Spanget-Larsen, J Waluk, J Mroz, BJ AF Radziszewski, JG Gil, M Gorski, A Spanget-Larsen, J Waluk, J Mroz, BJ TI Electronic states of the phenoxyl radical SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID RESONANCE RAMAN-SPECTRUM; THERMAL-DECOMPOSITION; UV SPECTRUM; SHOCK-WAVES; AB-INITIO; SPECTROSCOPY; KINETICS; CHEMISTRY; TYROSINE; FIELD AB The phenoxyl radical and two of its isotopomers were investigated by UV-VIS and IR polarization spectroscopy of molecular samples immobilized in cryogenic argon matrices. Analysis of the combined electronic and infrared linear dichroism data led to determination of absolute transition moment directions and symmetry assignments for four low-lying excited electronic states. The bands observed at 16 000, 25 200, 33 900, and 41 800 cm-1 were assigned to (2)A(1), B-2(1), (2)A(1), and B-2(1) pi-pi (*) states, respectively. A very weak transition observed in the near-infrared close to 8900 cm-1 was assigned to an optically forbidden B-2(2) n-pi (*) state. The electronic transitions predicted by time dependent density functional theory (TD-UB3LYP/cc-pVTZ) were in good agreement with the observed transitions. (C) 2001 American Institute of Physics. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. Colorado Sch Mines, Dept Chem Engn, Golden, CO 80401 USA. Polish Acad Sci, Inst Phys Chem, PL-01224 Warsaw, Poland. Roskilde Univ Ctr, Dept Chem, DK-4000 Roskilde, Denmark. RP Radziszewski, JG (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. RI Waluk, Jacek/C-8250-2011 NR 50 TC 66 Z9 66 U1 2 U2 21 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 1 PY 2001 VL 115 IS 21 BP 9733 EP 9738 DI 10.1063/1.1415465 PG 6 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 492CN UT WOS:000172151000014 ER PT J AU Redden, G Bargar, J Bencheikh-Latmani, R AF Redden, G Bargar, J Bencheikh-Latmani, R TI Citrate enhanced uranyl adsorption on goethite: An EXAFS analysis SO JOURNAL OF COLLOID AND INTERFACE SCIENCE LA English DT Letter DE surface complexation; adsorption; uranyl; uranium; U(VI); citrate; citric acid; tricarballylic acid; acetate; acetic acid; EXAFS; X-ray absorption spectroscopy; organic ligand ID ABSORPTION FINE-STRUCTURE; COMPLEXES; ION; SPECTROSCOPY; HEMATITE; ACIDS AB Citric acid promotes the adsorption of uranyl (U(VI) as UO(2)(2+)) on goethite (alpha -FeOOH) at pH less than or equal to 5. Enhanced adsorption does not appear to follow a simple stoichiometric relationship between total citrate and total uranyl. An excess of citric acid relative to uranyl, or a high concentration of surface-bound citrate is required. An extended X-ray absorption fine structure spectroscopy (EXAFS) study was conducted to help understand the surface interactions between citrate, UO(2)(2+), and goethite between pH 3.5 and pH 5.5. Two principal surface species were found to be necessary and sufficient to describe the uranyl EXAFS spectra for the range of adsorbed citrate concentrations studied. (The possibility of additional minor surface species has not been eliminated, but inherent uncertainties in the data do not permit their clear identification.) One species is identified as an inner-sphere, uranyl-goethite complex, which exists at pH 5.5 in the absence of citrate. A second species is interpreted to be an adsorbed uranyl + citrate complex, which displaces the binary uranyl-goethite complex as the concentration of adsorbed citrate increases. The EXAFS spectra from samples with intermediate adsorbed citrate concentrations were reproduced using linear combinations of the spectra from these two end-member species. The uranyl + citrate surface complex appears to dominate adsorbed uranyl speciation at ligand : metal ratios of 10:1, or when the total surface-bound citrate approaches saturation. Although the exact structural configuration for the uranyl + citrate surface complex cannot be identified at this time, coordination between uranyl and one or more citrate molecules appears to involve both a bidentate bond (four-membered ring structure) and a putative eight-membered ring structure. The distribution and type of surface species should provide useful constraints on the development of model simulations of surface complexation behavior in this system. (C) 2001 Academic Press. C1 Idaho Natl Lab, Idaho Falls, ID 83415 USA. Stanford Synchrotron Radiat Lab, Stanford, CA 94305 USA. Stanford Univ, Dept Civil & Environm Engn, Stanford, CA 94305 USA. RP Redden, G (reprint author), Idaho Natl Lab, POB 1625,MS 2208, Idaho Falls, ID 83415 USA. EM reddgd@inel.gov RI Bernier-Latmani, Rizlan/E-4398-2011 OI Bernier-Latmani, Rizlan/0000-0001-6547-722X NR 29 TC 50 Z9 51 U1 5 U2 17 PU ACADEMIC PRESS INC ELSEVIER SCIENCE 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 1 PY 2001 VL 244 IS 1 BP 211 EP 219 DI 10.1006/jcis.2001.7996 PG 9 WC Chemistry, Physical SC Chemistry GA 497PY UT WOS:000172465700027 ER PT J AU Sohn, H Farrar, CR Hunter, NF Worden, K AF Sohn, H Farrar, CR Hunter, NF Worden, K TI Structural health monitoring using statistical pattern recognition techniques SO JOURNAL OF DYNAMIC SYSTEMS MEASUREMENT AND CONTROL-TRANSACTIONS OF THE ASME LA English DT Article AB This paper casts structural health monitoring in the context of a statistical pattern recognition paradigm. Two pattern recognition techniques based on time series analysis are applied to fiber optic strain gauge data obtained from two different structural conditions of a surface-effect fast patrol boat. The first technique is based (oil a two-stage time series analysis combining Auto-Regressive (AR) and Auto-Regressive with eXogenous inputs (ARX) prediction models. The second technique employs an outlier analysis with the Mahalanobis distance measure. The main objective is to extract features and Construct a statistical model that distinguishes the signals recorded under the different structural conditions of the boat. These two techniques were successfully applied to the patrol boat different structural Conditions, data clearly distinguishing data sets obtained from different structural conditions. C1 Los Alamos Natl Lab, Engn Sci & Applicat Div, Engn Anal Grp, Los Alamos, NM 87545 USA. Los Alamos Natl Lab, Engn Sci & Applicat Div, Measurement Technol Grp, Los Alamos, NM 87545 USA. Univ Sheffield, Dept Mech Engn, Sheffield S1 3JD, S Yorkshire, England. RP Sohn, H (reprint author), Los Alamos Natl Lab, Engn Sci & Applicat Div, Engn Anal Grp, M-S C926, Los Alamos, NM 87545 USA. RI Farrar, Charles/C-6954-2012 NR 20 TC 185 Z9 190 U1 6 U2 31 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA THREE PARK AVE, NEW YORK, NY 10016-5990 USA SN 0022-0434 J9 J DYN SYST-T ASME JI J. Dyn. Syst. Meas. Control-Trans. ASME PD DEC PY 2001 VL 123 IS 4 BP 706 EP 711 DI 10.1115/1.1410933 PG 6 WC Automation & Control Systems; Instruments & Instrumentation SC Automation & Control Systems; Instruments & Instrumentation GA 505CX UT WOS:000172894900020 ER PT J AU Morin, C Ikeura-Sekiguchi, H Tyliszczak, T Cornelius, R Brash, JL Hitchcock, AP Scholl, A Nolting, F Appel, G Winesett, DA Kaznacheyev, K Ade, H AF Morin, C Ikeura-Sekiguchi, H Tyliszczak, T Cornelius, R Brash, JL Hitchcock, AP Scholl, A Nolting, F Appel, G Winesett, DA Kaznacheyev, K Ade, H TI X-ray spectromicroscopy of immiscible polymer blends: polystyrene-poly(methyl methacrylate) SO JOURNAL OF ELECTRON SPECTROSCOPY AND RELATED PHENOMENA LA English DT Article DE soft X-ray microscopy; NEXAFS; DS; PMMA; polymer blends; phase segregation; quantitative chemical mapping ID PHASE-SEPARATION; THIN-FILMS; POLY(METHYL METHACRYLATE); SURFACE; MICROSCOPE; POLYSTYRENE; MORPHOLOGY; BILAYER; BULK AB Spun cast thin films of blends of low and high molecular weight mono-disperse polystyrene (PS) and poly(methyl methacrylate) (PMMA) with nominal compositions ranging from 66/33 wt.%/wt.% (w/w) up to 10/90 w/w PS/PMMA have been studied, as-made and after annealing. Two synchrotron-based X-ray microscopies - scanning transmission X-ray microscopy (STXM) and X-ray photoemission electron microscopy (X-PEEM) - as well as several variants of atomic force microscopy (AFM) were used to probe the composition and morphology of the bulk and surface of these blends. The chemical sensitivities and spatial resolutions of these three techniques are compared. All samples are observed to have a PS signal in the C Is X-ray absorption spectrum of the surface of the PMMA-rich domains as measured in the X-PEEM. A continuous thin PS laver is not expected at a PMMA surface since neither polymer should wet the other at thermodynamic equilibrium, The likely origin of this PS surface signal is from a bimodal distribution of PS domain sizes with the PS signal arising from domains at the surface which are smaller than the similar to 200-nm resolution of the X-PEEM. High resolution AFM and STXM provide direct evidence for this explanation. (C) 2001 Elsevier Science B.V. All rights reserved. C1 McMaster Univ, Dept Chem, BIMR, Hamilton, ON L8S 4M1, Canada. Lawrence Berkeley Lab, Adv Light Source, Berkeley, CA 94720 USA. N Carolina State Univ, Dept Phys, Raleigh, NC 27695 USA. RP Hitchcock, AP (reprint author), McMaster Univ, Dept Chem, BIMR, 1280 Main St W, Hamilton, ON L8S 4M1, Canada. RI Ade, Harald/E-7471-2011; Scholl, Andreas/K-4876-2012 NR 40 TC 56 Z9 56 U1 0 U2 15 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 2001 VL 121 IS 1-3 BP 203 EP 224 DI 10.1016/S0368-2048(01)00335-8 PG 22 WC Spectroscopy SC Spectroscopy GA 494MV UT WOS:000172287200014 ER PT J AU Luning, J Yoon, DY Stohr, J AF Luning, J Yoon, DY Stohr, J TI Importance of structural order for the low surface energy of perfluoroalkyl substituted polymethacrylates SO JOURNAL OF ELECTRON SPECTROSCOPY AND RELATED PHENOMENA LA English DT Article DE low surface energy coatings; perfluoroalkyl substituted polymethacrylates ID TRANSFER RADICAL POLYMERIZATION; X-RAY-ABSORPTION; BLOCK-COPOLYMERS; FINE-STRUCTURE; SPECTRA; FILMS; EDGE; ORIENTATION; POLYMERS; NEXAFS AB Low surface energy coatings or anti-wetting agents play an essential role in microelectronics, anti-fogging and anti-fouling applications, and even have promising medical applications. Currently, perfluoroalkyl substituted polymethacrylates (PFPMs) are widely in use, and the anti-wetting proper-ties of these and related polymers are believed to arise from the segregation of CF, groups to the surface. However, proof of a direct correlation between surface energies and surface structure, and the importance of the order in the underlying bulk is still lacking. Here we report near edge X-ray absorption fine structure (NEXAFS) results which establish such a correlation. Our studies of three PFPMs with, respectively, isotropic, nematic, and smectic A bulk phases at room temperature reveal in all cases a greater order at the surface than in the bulk. The surface order parameter is found to correlate with the surface energy, which we find indeed to be lowered by segregation of CF, groups to the film surface. Most importantly, temperature dependent NEXAFS measurements in the 20-140 degreesC range, covering bulk phase transitions from smectic A to nematic to isotropic, show that it is the bulk order (phase) which ultimately limits the achievable surface order, and hence the surface properties. (C) 2001 Elsevier Science BY. All rights reserved. C1 Stanford Synchrotron Radiat Lab, Stanford, CA 94209 USA. Seoul Natl Univ, Sch Chem, Seoul 151747, South Korea. RP Luning, J (reprint author), Stanford Synchrotron Radiat Lab, MS 69,POB 20450, Stanford, CA 94209 USA. NR 40 TC 13 Z9 13 U1 1 U2 10 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 2001 VL 121 IS 1-3 BP 265 EP 279 DI 10.1016/S0368-2048(01)00339-5 PG 15 WC Spectroscopy SC Spectroscopy GA 494MV UT WOS:000172287200018 ER PT J AU Shaw, MJ Grunow, S Duquette, DJ AF Shaw, MJ Grunow, S Duquette, DJ TI "Seedless" electrochemical deposition of copper on physical vapor deposition-W2N liner materials for ultra large scale integration (ULSI) devices SO JOURNAL OF ELECTRONIC MATERIALS LA English DT Article; Proceedings Paper CT Symposium on Materials and Processes for Submicron Technologies CY FEB, 2001 CL NEW ORLEANS, LOUISIANA SP TMS Elec Magne & Photon Mat Div, Thin Films & Interfaces Comm, ASM Int Mat Sci Crit Technol Sector DE tungsten nitride; copper; electrochemical; seedless; diffusion barrier AB Electrochemical studies are designed to identify processes that provide adequate nucleation and thin film growth directly on ultrathin, air-exposed physical vapor deposition (PVD)-tungsten nitride diffusion barriers. In this study, it is shown that very thin copper films can be nucleated directly on a conducting PVD-W2N liner surface. A complex chemistry model based on mass balance and thermodynamic equilibrium has been applied to numerous ammoniacal platting bath compositions and the resulting concentration profiles inserted into the Nernst equation. Comparing the experimental results with the predicted model indicates that a strong adhesion is associated with the reduction of several copper-ammonia complexes at the metal nitride surface, Nucleation, growth mechanisms, and film resistivity are found to be dependent on the reduction potential, electrolyte velocity, and platting bath chemistry. C1 Rensselaer Polytech Inst, Troy, NY 12018 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. Univ Albany, NYS Ctr Adv Thin Film Technol, Albany, NY USA. Univ Albany, Dept Phys, Albany, NY USA. RP Shaw, MJ (reprint author), Rensselaer Polytech Inst, 110 8th St, Troy, NY 12018 USA. NR 17 TC 19 Z9 19 U1 1 U2 3 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086 USA SN 0361-5235 J9 J ELECTRON MATER JI J. Electron. Mater. PD DEC PY 2001 VL 30 IS 12 BP 1602 EP 1608 DI 10.1007/s11664-001-0179-8 PG 7 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Physics, Applied SC Engineering; Materials Science; Physics GA 513ZK UT WOS:000173411100020 ER PT J AU Sopori, B Zhang, Y Ravindra, NM AF Sopori, B Zhang, Y Ravindra, NM TI Silicon device processing in H-ambients: H-diffusion mechanisms and influence on electronic properties SO JOURNAL OF ELECTRONIC MATERIALS LA English DT Article; Proceedings Paper CT Symposium on Materials and Processes for Submicron Technologies CY FEB, 2001 CL NEW ORLEANS, LA SP TMS, Electr Magnet & Photon Mat Div, Thin Films & Interfaces Comm, ASM Int Mat Sci Crit Technol Sector DE solar cells; hydrogen; passivation; impurities; defects ID OXIDE-SEMICONDUCTOR TRANSISTORS; HOT-CARRIER RELIABILITY; HYDROGENATED AMORPHOUS-SILICON; ENHANCED OXYGEN DIFFUSION; INDUCED INTERFACE STATES; SINGLE-CRYSTAL SILICON; POLYCRYSTALLINE SILICON; ELECTRICAL-PROPERTIES; CONDUCTIVITY CHANGES; SELF-INTERSTITIALS AB Hydrogen is an electronically active impurity in Si with some unique properties-it can passivate other impurities and defects, both at the interface and in the bulk. Controlled introduction of H can lower interface state density, and thereby improve Schottky and MOS devices, and can reduce bulk recombination to increase minority-carrier-controlled device performance. However, excess H can also introduce defects that can be detrimental to the device properties. Although H is typically introduced by exposing the device to a flux of atomic species, a suitable device configuration can be passivated by thermal treatment in forming gas. This paper addresses some basic issues of device processing in H ambient to improve device performance. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. New Jersey Inst Technol, Dept Phys, Newark, NJ 07102 USA. RP Sopori, B (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 73 TC 24 Z9 24 U1 1 U2 9 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0361-5235 J9 J ELECTRON MATER JI J. Electron. Mater. PD DEC PY 2001 VL 30 IS 12 BP 1616 EP 1627 DI 10.1007/s11664-001-0181-1 PG 12 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Physics, Applied SC Engineering; Materials Science; Physics GA 513ZK UT WOS:000173411100022 ER PT J AU Dahlburg, J Corones, J Batchelor, D Bramley, R Greenwald, M Jardin, S Krasheninnikov, S Laub, A Leboeuf, JN Lindl, J Lokke, W Rosenbluth, M Ross, D Schnack, D AF Dahlburg, J Corones, J Batchelor, D Bramley, R Greenwald, M Jardin, S Krasheninnikov, S Laub, A Leboeuf, JN Lindl, J Lokke, W Rosenbluth, M Ross, D Schnack, D TI Fusion simulation project: Integrated simulation and optimization of magnetic fusion systems SO JOURNAL OF FUSION ENERGY LA English DT Article DE plasma simulation; magnetic confinement AB This is the final report of a panel established as a subcommittee of the U. S. Department of Energy (DOE) Fusion Energy Sciences Committee (FESAC) on Integrated Simulation and Optimization of Magnetic Fusion Systems (ISOFS). The report was requested by the DOE in February 2002 and the approved report was transmitted to the DOE by the FESAC in December 2002. The report addresses the challenge of how to "develop fully integrated capability for predicting the performance of externally-controlled systems including turbulent transport, macroscopic stability, wave-particle physics, and multi-phase interfaces". C1 Gen Atom Co, Energy Grp, San Diego, CA 92186 USA. Oak Ridge Natl Lab, Oak Ridge, TN USA. Indiana Univ, Bloomington, IN 47405 USA. MIT, Cambridge, MA 02139 USA. Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. Univ Calif San Diego, San Diego, CA 92103 USA. Univ Calif Davis, Davis, CA 95616 USA. Univ Calif Los Angeles, Los Angeles, CA USA. Lawrence Livermore Natl Lab, Livermore, CA USA. Univ Texas, Austin, TX 78712 USA. Sci Applicat Int Corp, Mclean, VA 22102 USA. RP Dahlburg, J (reprint author), Gen Atom Co, Energy Grp, POB 85608, San Diego, CA 92186 USA. RI Jardin, Stephen/E-9392-2010; OI Greenwald, Martin/0000-0002-4438-729X NR 0 TC 10 Z9 10 U1 0 U2 0 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0164-0313 J9 J FUSION ENERG JI J. Fusion Energy PD DEC PY 2001 VL 20 IS 4 BP 135 EP 196 DI 10.1023/A:1023433001854 PG 62 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 671BG UT WOS:000182444700003 ER PT J AU Becker, A Klock, W Friese, K Schreck, P Treutler, HC Spettel, B Duff, MC AF Becker, A Klock, W Friese, K Schreck, P Treutler, HC Spettel, B Duff, MC TI Lake Susser See as a natural sink for heavy metals from copper mining SO JOURNAL OF GEOCHEMICAL EXPLORATION LA English DT Article DE lake sediments; heavy metals; crystal chemistry; speciation; human activity; mining ID X-RAY-ABSORPTION AB Lake Susser See, west of Halle, Germany, is a natural sink for heavy metals, which are abundant in the streams crossing the Mansfeld copper shale mining and smelting district in Central Germany. The lake and its environment serve as a recreational area for the local residents. We investigated the vertical distribution of key metals such as Cu, Pb and Zn in the lake sediments. To estimate the future stability of the heavy metals in the lake sediments, speciation analysis of the metals was carried out on selected samples using several analytical methods, including X-ray diffraction, synchrotron-based X-ray fluorescence imaging, microprobe X-ray absorption near-edge structure spectroscopy and scanning electron microscopy. The lake sediments contain up to 5% Zn, 5000 ppm Pb, 4500 ppm Cu and 2000 ppm As. These maximum values are reached within the upper 60 cm of the sediment. There is a general trend of decreasing metal concentrations with depth. Several potential metal sources of geogenic and anthropogenic pollutants have to be taken into account. Pollutants of geogenic origin are mainly heavy metals from the outcropping copper shale at the periphery of the Mansfeld geosyncline. Man-made pollutants are dominated by seepage from the mine tailings and smelting products of copper shale mining (in particular scrubber dust, `Theisen-sludge'). Trace elements and their ratios in the lake sediments can serve as geochemical tracers. These tracers could help to identify the main sources of pollution. The data show that scrubber dust is the main carrier of the heavy metal contamination in the lake sediments. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Halle Wittenberg, Inst Geol Sci & Geiseltalmuseum, D-06108 Halle An Der Saale, Saale, Germany. UFZ Helmholtz Ctr Environm Res, Dept Inland Water Res, D-39114 Magdeburg, Germany. Univ Leipzig, Inst Geophys & Geol, D-04103 Leipzig, Germany. UFZ Helmholtz Ctr Environm Res, Dept Analyt Chem, D-01103 Leipzig, Germany. Max Planck Inst Chem, D-55122 Mainz, Germany. Westinghouse Savannah River Co, Savannah River Technol Ctr, Aiken, SC 29808 USA. RP Becker, A (reprint author), Univ Halle Wittenberg, Inst Geol Sci & Geiseltalmuseum, Domstr 5, D-06108 Halle An Der Saale, Saale, Germany. EM becker@geologie.uni-halle.de; kloeck@geologie.uni-halle.de; friese@degeo.ufop.br; schreck@rz.uni-leipzig.de; treutler@ana.ufz.de; martine.duff@srs.gov RI Friese, Kurt/E-1395-2012 OI Friese, Kurt/0000-0002-7769-0818 NR 9 TC 13 Z9 16 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-6742 J9 J GEOCHEM EXPLOR JI J. Geochem. Explor. PD DEC PY 2001 VL 74 IS 1-3 BP 205 EP 217 DI 10.1016/S0375-6742(01)00185-6 PG 13 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 499BQ UT WOS:000172551500013 ER PT J AU Borovsky, JE Bonnell, J AF Borovsky, JE Bonnell, J TI The dc electrical coupling of flow vortices and flow channels in the magnetosphere to the resistive ionosphere SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID AURORAL ARC; MAGNETIC-FIELD; PLASMA SHEET; BLACK AURORA; DOUBLE-LAYER; CURRENTS; CONVECTION; POTENTIALS; SIGNATURES; REGIONS AB The dc electrical coupling of magnetospheric flow vortices and magnetospheric flow channels to the ionosphere is numerically calculated. The equations governing the coupling are derived from current continuity plus Ohm's laws taken for the regions of field-aligned current between the ionosphere and magnetosphere and for the Pedersen layer of the ionosphere. For vortices the strength of the coupling (as measured by fractional penetration of the magnetospheric electric fields down to the ionosphere and by the amount of power dissipation) varies, as expected, with the size of the vortex footprint in the ionosphere. However, because of the diode-like nature of the field-aligned currents, the coupling also varies with sign of the vorticity: Positive center vortices (vorticity antiparallel to B) couple much more strongly than do negative center vortices (vorticity parallel to B). Negative center vortices tend to dissipate most of their energy in parallel currents, whereas positive center vortices dissipate most of their energy in Pedersen currents. The electric fields of positive center vortices spread across B as they connect to the ionosphere, whereas the electric fields of negative center vortices stay confined to their magnetic footprints. Consequently, positive center vortices in the magnetosphere produce quasi-circular vortices of flow in the ionosphere whereas negative center vortices in the magnetosphere produce narrow east-west-elongated vortices of flow in the ionosphere. Negative center vortices in the magnetosphere could produce east-west-aligned bright are-like features, and positive center vortices could produce east-west-aligned black-arc features imbedded in large circular patches of aurora. Flow channels in the magnetosphere drive field-aligned currents into the ionosphere: The upward field-aligned current on the negative-charged edge of the channel tends to spread across B, whereas downward current on the positive charge edge tends to stay confined. In the magnetosphere the current spreading results in a back emf that produces a backward flow outside the flow channel on the negative-charged edge. C1 Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. Los Alamos Natl Lab, Space & Atmospher Sci Grp, Los Alamos, NM 87545 USA. RP Borovsky, JE (reprint author), Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. NR 55 TC 14 Z9 14 U1 0 U2 5 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 2001 VL 106 IS A12 BP 28967 EP 28994 DI 10.1029/1999JA000245 PG 28 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 519LV UT WOS:000173728500014 ER PT J AU Zank, GP Rice, WKM Cairns, IH Bieber, JW Skoug, RM Smith, CW AF Zank, GP Rice, WKM Cairns, IH Bieber, JW Skoug, RM Smith, CW TI Predicted timing for the turn-on of radiation in the outer heliosphere due to the Bastille Day shock SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID INTERPLANETARY RADIO EMISSIONS; INTERSTELLAR NEUTRAL HYDROGEN; EARTHS BOW SHOCK; SOLAR-WIND; TERMINATION SHOCK; PICKUP IONS; ENERGETIC PARTICLES; SOURCE REGION; COSMIC-RAYS; HELIOPAUSE AB The propagation of the July 14, 2000 (Bastille Day), shock complex is modeled throughout the heliosphere, including its interaction with the solar wind termination shock and subsequent propagation into the inner heliosheath. The model includes pickup ions and the ionization cavity explicitly. The Bastille Day shock is used (1) to predict the time when the Voyager spacecraft can expect to observe 2- to 3-kHz radiation and (2) to place constraints on the distance to the heliopause in the upwind or nose direction. On the basis of the most widely accepted model for the generation of the 2- to 3-kHz radiation, we predict that the Bastille Day shock, were it to produce observable radiation in the outer heliosheath, would turn on in mid-October 2001. The distance to the heliopause at the nose is then estimated to be <120-130 AU, and the distance to the termination shock is estimated to be <90 AU. A further conclusion is that transmitted interplanetary shocks are very weak when they enter the outer heliosheath, the putative site at which interplanetary shocks radiate, thus requiring that the interstellar plasma in this region be primed with a preexisting energized electron population. C1 Univ Delaware, Bartol Res Inst, Sharp Lab, Newark, DE 19716 USA. Univ Sydney, Sch Phys A28, Sydney, NSW 2006, Australia. Los Alamos Natl Lab, Grp NIS1, Los Alamos, NM 87545 USA. RP Zank, GP (reprint author), Univ Calif Riverside, Inst Geophys & Planetary Phys, Riverside, CA 92521 USA. RI Rice, Ken/H-5084-2011; OI Rice, Ken/0000-0002-6379-9185; Cairns, Iver/0000-0001-6978-9765 NR 46 TC 11 Z9 11 U1 0 U2 0 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 2001 VL 106 IS A12 BP 29363 EP 29372 DI 10.1029/2000JA000401 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 519LV UT WOS:000173728500044 ER PT J AU Zeng, W Horwitz, JL Stevenson, BA Wu, XY Su, YJ Craven, PD Rich, FJ Moore, TE Tu, JN AF Zeng, W Horwitz, JL Stevenson, BA Wu, XY Su, YJ Craven, PD Rich, FJ Moore, TE Tu, JN TI Near-simultaneous Polar and DMSP measurements of topside ionospheric field-aligned flows at high latitudes SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID SOFT-ELECTRON-PRECIPITATION; F-REGION; WIND; MODEL; IONS; O+; MAGNETOSPHERE; OUTFLOW; CONICS; CAP AB Near-simultaneous observations of topside O+ parallel flows are presented for four periods of measurement by the Polar and DMSP satellites during April 1996. The Polar measurements were from southern perigee measurements near 5000 km altitude, while the DMSP measurements were from 840 km altitude. In general, the velocities were upward at expected cleft and auroral latitudes, typically about 2-10 km s(-1) at 5000 km altitude, and 0-2 km s(-1) at 840 km altitude. At the highest, polar cap latitudes, downward velocities were more frequent at both altitudes, but especially at the lower 840 km altitude. The downward velocities were typically a few hundred meters per second at 840 km altitude, and 0-1 km s(-1) at 5000 km altitude. In some instances, downward velocities were observed at 840 km altitude while upward O+ flows were observed at 5000 km altitude, possibly on the same flux tube. The O+ densities were characteristically 1-10 O+ cm(-3) at 5000 km altitude and 10(3) -10(4) O+ cm(-3) at 840 km altitude, while the O+ fluxes were characteristically 10(5) - 10(7) O+ cm(-1) s(-1) at 5000 km altitude and characteristically 10(7) - 10(9) O+ cm(-2) s(-1) at 840 km altitude. We have also examined the dual-altitude parameter measurements for a polar cap field line, the Polar and DMSP measurements approximately 30 min apart, and compared them with results from a transport simulation. The simulated high-altitude velocity altitude profiles for the period during and after the initiation of the auroral processes generally bracketed the observations, but the observed downward velocities (500 - 600 m s(-1)) at 840 km altitude were much larger in magnitude than those in the transport simulation, and the simulated densities were several times higher than those observed at both altitudes. C1 Univ Alabama, Ctr Space Plasma & Aeronom Res, Huntsville, AL 35899 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. NASA, George C Marshall Space Flight Ctr, Dept Space Sci, Huntsville, AL 35805 USA. USAF, Res Lab, Hanscom AFB, MA 01731 USA. NASA, Goddard Space Flight Ctr, Extraterr Phys Lab, Greenbelt, MD 20771 USA. RP Zeng, W (reprint author), Univ Alabama, Ctr Space Plasma & Aeronom Res, Huntsville, AL 35899 USA. RI Moore, Thomas/D-4675-2012; OI Moore, Thomas/0000-0002-3150-1137; Stevenson, Benjamin/0000-0001-9918-1240 NR 28 TC 4 Z9 4 U1 0 U2 0 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 2001 VL 106 IS A12 BP 29601 EP 29610 DI 10.1029/2000JA000332 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 519LV UT WOS:000173728500064 ER PT J AU Korth, H Thomsen, MF AF Korth, H Thomsen, MF TI Plasma sheet access to geosynchronous orbit: Generalization to numerical global field models SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID MAGNETOSPHERIC ELECTRIC-FIELDS; DEPENDENT MODEL; TAIL; POTENTIALS AB A previous statistical analysis of the geosynchronous particle environment by Korth et al. [1999] showed that the particle fluxes are well organized by local time and the geomagnetic activity as measured by the Kp index. Regions of high and low fluxes at geosynchronous orbit are separated from each other by distinct boundaries, approximately matching the Alfven boundary crossings of the geosynchronous satellites calculated analytically from a Volland-Stern electric potential and a dipole magnetic field. Expanding the analysis technique from the previous work to arbitrary, numerical electric and magnetic field models, we reevaluate the Alfven boundary crossings using several available global electric potential models and considering external magnetic field contributions. The more sophisticated numerical models do not do a better job of explaining the observed average access of plasma sheet material to the geosynchronous region than does the simple analytical model. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Korth, H (reprint author), Los Alamos Natl Lab, NIS-1,MS D466, Los Alamos, NM 87545 USA. NR 28 TC 21 Z9 21 U1 0 U2 2 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 2001 VL 106 IS A12 BP 29655 EP 29667 DI 10.1029/2000JA000373 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 519LV UT WOS:000173728500069 ER PT J AU Hesse, M Kuznetsova, M Birn, J AF Hesse, M Kuznetsova, M Birn, J TI Particle-in-cell simulations of three-dimensional collisionless magnetic reconnection SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID THIN CURRENT SHEETS; MAGNETOSPHERIC SUBSTORMS; ELECTRON DISSIPATION; EARTHS MAGNETOPAUSE; KINK INSTABILITY; DYNAMICS; MAGNETOTAIL; MECHANISM; REGION; MODEL AB Three-dimensional simulations of collisionless magnetic reconnection in a current sheet configuration are presented. The study consists of two parts: a simulation of a current sheet with an initial perturbation and another model run without it. Particular emphasis is on the questions (1) whether magnetic reconnection remains two-dimensional if it initiates so, and (2) whether reconnection favors a patchy, localized mode over long, extended reconnection regions. Our study suggests that results from 2.5-dimensional models of reconnection are not substantially altered by including variations in the third dimension. In fact, an initially random patchy reconnection structure appear to self-organize into a more coherent quasi-two-dimensional structure. As in 2.5-dimensional reconnection studies, the dominant contribution to the dissipation stems from off-diagonal terms of the electron pressure tensor in our simulations. The dominant term is related to oscillatory electron motions between the regions of newly reconnected magnetic field. C1 NASA, Goddard Space Flight Ctr, Electrodynam Branch, Greenbelt, MD 20771 USA. RP Hesse, M (reprint author), Los Alamos Natl Lab, Space Sci Grp, POB 1663, Los Alamos, NM 87544 USA. RI Hesse, Michael/D-2031-2012; Kuznetsova, Maria/F-6840-2012 NR 42 TC 36 Z9 38 U1 0 U2 2 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 2001 VL 106 IS A12 BP 29831 EP 29841 DI 10.1029/2001JA000075 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 519LV UT WOS:000173728500080 ER PT J AU Moon, YJ Choe, GS Yun, HS Park, YD AF Moon, YJ Choe, GS Yun, HS Park, YD TI Flaring time interval distribution and spatial correlation of major X-ray solar flares SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID SELF-ORGANIZED CRITICALITY; FREQUENCY-DISTRIBUTIONS; AVALANCHES AB A statistical study is performed on X-ray flares stronger than C1 class that erupted during the solar maximum between 1989 and 1991. We have investigated the flaring time interval distribution (waiting-time distribution) and the spatial correlation of successive flare pairs. The observed waiting-time distribution for the whole data is found to be well represented by a nonstationary Poisson probability function with time-varying mean flaring rates. The period most suitable for a constant mean flaring rate is determined to be 2-3 days by a Kolmogorov-Smirnov test. We have also found that the waiting-time distribution for flares in individual active regions follows a stationary Poisson probability function m exp(-mt) with a corresponding mean flaring rate. Therefore the flaring probability within a given time is given by 1 - exp(-mt), when the mean flaring rate m is properly estimated. It is also found that there are no systematic relationships between peak fluxes of flares and their waiting-time distributions. The above findings support the idea that the solar corona is in a self-organized critical state. A comparison of the angular distances of successively observed flare pairs with those of hypothetical flare pairs generated by random distribution shows a positive angular correlation within similar to 10degrees (similar to 180 arc sec in the observing field) of angular separation, which suggests that homologous flares occurring in the same active region should outnumber sympathetic flares. C1 Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. Korea Astron Observ, Taejon, South Korea. Seoul Natl Univ, Sch Earth & Environm Sci, Astron Program, Seoul, South Korea. RP Moon, YJ (reprint author), Korea Astron Observ, Taejon, South Korea. RI Moon, Yong-Jae/E-1711-2013; Choe, Gwangson/E-2366-2013 NR 25 TC 42 Z9 42 U1 1 U2 2 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 2001 VL 106 IS A12 BP 29951 EP 29961 DI 10.1029/2000JA000224 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 519LV UT WOS:000173728500094 ER PT J AU Khan, H Cowley, SWH Kolesnikova, E Lester, M Brittnacher, MJ Hughes, TJ Hughes, WJ Kurth, WS McComas, DJ Newitt, L Owen, CJ Reeves, GD Singer, HJ Smith, CW Southwood, DJ Watermann, JF AF Khan, H Cowley, SWH Kolesnikova, E Lester, M Brittnacher, MJ Hughes, TJ Hughes, WJ Kurth, WS McComas, DJ Newitt, L Owen, CJ Reeves, GD Singer, HJ Smith, CW Southwood, DJ Watermann, JF TI Observations of two complete substorm cycles during the Cassini Earth swing-by: Cassini magnetometer data in a global context SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID AURORAL KILOMETRIC RADIATION; HIGH-LATITUDE CONVECTION; CURRENT DISRUPTION; RADAR OBSERVATIONS; ELECTRIC-FIELDS; CURRENT WEDGE; FLOW; MAGNETOSPHERE; MAGNETOTAIL; MODEL AB During the Earth swing-by of the Cassini spacecraft, a worldwide program of data-gathering was undertaken to define the prevailing interplanetary and geophysical conditions. This included observations of the interplanetary medium, outer magnetosphere, geostationary orbit, UV aurora, geomagnetic disturbance, and ionospheric flow. These data show that during the Cassini outbound passage through the geomagnetic tail the magnetosphere underwent two complete "classic" substorm cycles. The global data are used to set the Cassini data into a context which allows a much fuller interpretation. The pass took place through the dawn tail, where previous Geotail observations indicate that the plasma sheet usually remains 'stationary' at expansion phase onset. Reconnection and plasmoid formation are typically dusk and midnight phenomena. The Cassini observations nevertheless show a marked response of the plasma sheet both to the growth phase (thinning), and expansion phase onset (expansion without heating). Subsequent impulsive expansion of the substorm into the Cassini sector, however, resulted in the prompt appearance of reconnection-related phenomena (earthward flowing plasma and strongly disturbed fields), though the spacecraft footprint remained poleward of the intense UV auroras. Due to continuing strong southward-directed IMF during the expansion phases, a quasi-equilibrium appears to have formed between dayside and near-Earth nightside reconnection for similar to30 min after onset. Auroral zone recovery began about similar to10 min after a northward turn of the interplanetary magnetic field (IMF) to nearer-zero values in each case. A net closure of open flux then ensued, leading to deflation of the tail lobe field, 'dipolarization' of the near-Earth tail plasma sheet field, simultaneous reduction in the earthward plasma sheet flow and the flow in the nightside ionosphere, and displacement of the ground-based disturbance to high latitudes. C1 Univ Leicester, Dept Phys & Astron, Leicester LE1 7RH, Leics, England. Univ Washington, Geophys Programme, Seattle, WA 98195 USA. Canadian Space Agcy, Vanier, ON K1L 8E3, Canada. Boston Univ, Ctr Space Phys, Boston, MA 02215 USA. Univ Iowa, Dept Phys & Astron, Iowa City, IA 52242 USA. SW Res Inst, San Antonio, TX 78238 USA. Geol Survey Canada, Ottawa, ON K1A 0Y3, Canada. UCL, Mullard Space Sci Lab, Dorking RH5 6NT, Surrey, England. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. NOAA, Space Environm Ctr, Boulder, CO 80303 USA. Univ Delaware, Bartol Res Inst, Newark, DE 19716 USA. Univ London Imperial Coll Sci Technol & Med, Blackett Lab, London SW7 2BZ, England. Danish Meteorol Inst, DK-2100 Copenhagen, Denmark. RP Khan, H (reprint author), Univ Leicester, Dept Phys & Astron, Leicester LE1 7RH, Leics, England. EM hina.khan@ion.le.ac.uk RI Owen, Christopher/C-2999-2008; Reeves, Geoffrey/E-8101-2011; OI Owen, Christopher/0000-0002-5982-4667; Reeves, Geoffrey/0000-0002-7985-8098; Kurth, William/0000-0002-5471-6202 NR 54 TC 11 Z9 11 U1 0 U2 2 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 2001 VL 106 IS A12 BP 30141 EP 30175 DI 10.1029/2001JA900049 PG 35 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 519LV UT WOS:000173728500110 ER PT J AU Rymer, AM Coates, AJ Svenes, K Abel, GA Linder, DR Narheim, B Thomsen, M Young, DT AF Rymer, AM Coates, AJ Svenes, K Abel, GA Linder, DR Narheim, B Thomsen, M Young, DT TI Cassini Plasma Spectrometer Electron Spectrometer measurements during the Earth swing-by on August 18, 1999 SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID SOLAR-WIND CONTROL; MAGNETOSPHERE; MAGNETOPAUSE; MAGNETOSHEATH; ENCOUNTER; MISSION; LAYER; SHAPE; FLOW AB On August 18, 1999, Cassini flew by the Earth on its way to Saturn. The Cassini Earth swing-by was the fastest traversal of the Earth's magnetosphere to date. The spacecraft was traveling at 9.1 R(E) hr(-1) (16.1 km s(-1)) and made rapid traversals of several regions of the terrestrial magnetosphere. During the Cassini Earth swing-by the Electron Spectrometer (ELS) collected almost 9 hours of data in the Earth's magnetosphere and almost 10 hours of solar wind data upstream of the Earth. During the pass, Cassini ELS sampled electrons in the solar wind, bow shock, magnetosheath, magnetopause, radiation belts, plasmasphere, plasma sheet, lobes, and crossings of the tail magnetopause. The purpose of this paper is (1) to give a summary of electron observations including the locations of magnetosphere boundary crossings and (2) to assess how the ELS is functioning as it takes measurements in the greatly differing plasma regimes encountered. Results are shown to be mainly consistent with previous observations with a few exceptions. In addition to anticipated results we present evidence of a low-energy field-aligned beam in the plasma sheet and evidence of asymmetry on the dayside and nightside plasmapause position. Preliminary calculations of density and temperature for the solar wind, magnetosheath, and plasma sheet are also presented. C1 UCL, Mullard Space Sci Lab, Dorking RH5 6NT, Surrey, England. Norwegian Def Res Estab, N-2027 Kjeller, Norway. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Michigan, Dept Atmospher Ocean & Space Sci, Ann Arbor, MI 48109 USA. RP Rymer, AM (reprint author), UCL, Mullard Space Sci Lab, Holmbury St Mary, Dorking RH5 6NT, Surrey, England. EM amr@mssl.ucl.ac.uk; ajc@mssl.ucl.ac.uk; knut.svenes@ffi.no; gaab@bas.ac.uk; drl@mssl.ucl.ac.uk; t.narheim@ffi.no; mthomsen@lanl.gov; dtyoung@umich.edu RI Coates, Andrew/C-2396-2008 OI Coates, Andrew/0000-0002-6185-3125 NR 41 TC 6 Z9 6 U1 0 U2 0 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 2001 VL 106 IS A12 BP 30177 EP 30198 DI 10.1029/2001JA900087 PG 22 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 519LV UT WOS:000173728500111 ER PT J AU Abel, GA Coates, AJ Rymer, AM Linder, DR Thomsen, MF Young, DT Dougherty, MK AF Abel, GA Coates, AJ Rymer, AM Linder, DR Thomsen, MF Young, DT Dougherty, MK TI Cassini Plasma Spectrometer observations of bidirectional lobe electrons during the Earth flyby, August 18, 1999 SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID POLAR RAIN; DISTANT TAIL; SOLAR-WIND; MAGNETOSPHERE AB Unlike previous missions to the magnetotail (IMP 6, ISEE 1, ISEE 3, and Geotail), which effectively made observations in the lobe at a single downtail distance, the Cassini Earth swingby allowed, for the first time, near-continuous observations covering a range of downtail distances. Bidirectional electrons are found in the northern lobe, consistent with previous studies. Enhancements in the electron fluxes are seen in a boundary layer between the lobe and sheath. These enhancements are accompanied by enhancements in ion fluxes traveling tailward. We also present what we believe to be the first observations of a returning electron population in the magnetosheath. Bidirectional electrons are observed upto 0.02 keV, while at higher energies only unidirectional electrons are observed. The low energy of the returning electrons arises as a. result of the electron populations' passage through the magnetopause twice and losses due to precipitation. C1 UCL, Mullard Space Sci Lab, Dorking RH5 6NT, Surrey, England. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Michigan, Dept Atmospher Ocean & Space Sci, Ann Arbor, MI 48109 USA. Univ London Imperial Coll Sci Technol & Med, Blackett Lab, London SW7 2BZ, England. RP Abel, GA (reprint author), British Antarctic Survey, High Cross,Madingley Rd, Cambridge CB3 0ET, England. EM gaab@bas.ac.uk; ajc@mssl.ucl.ac.uk; amr@mssl.ucl.ac.uk; drl@mssl.ucl.ac.uk; mthomsen@lanl.gov; dtyoung@umich.edu; m.dougherty@ic.ac.uk RI Coates, Andrew/C-2396-2008 OI Coates, Andrew/0000-0002-6185-3125 NR 19 TC 4 Z9 4 U1 0 U2 0 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 2001 VL 106 IS A12 BP 30199 EP 30208 DI 10.1029/2001JA900076 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 519LV UT WOS:000173728500112 ER PT J AU Ryan, TJ Swenson, G AF Ryan, TJ Swenson, G TI Does sex influence postreproductive metamorphosis in Ambystoma talpoideum? SO JOURNAL OF HERPETOLOGY LA English DT Article ID SALAMANDER; PEDOMORPHOSIS; HETEROCHRONY; EVOLUTION; STEROIDS C1 Savannah River Ecol Lab, Aiken, SC 29802 USA. Univ Missouri, Div Biol Sci, Columbia, MO 65211 USA. RP Ryan, TJ (reprint author), Butler Univ, Dept Biol Sci, Indianapolis, IN 46208 USA. NR 18 TC 1 Z9 1 U1 0 U2 0 PU SOC STUDY AMPHIBIANS REPTILES PI ST LOUIS PA C/O ROBERT D ALDRIDGE, ST LOUIS UNIV, DEPT BIOLOGY, 3507 LACLEDE, ST LOUIS, MO 63103 USA SN 0022-1511 J9 J HERPETOL JI J. Herpetol. PD DEC PY 2001 VL 35 IS 4 BP 697 EP 700 DI 10.2307/1565917 PG 4 WC Zoology SC Zoology GA 502YJ UT WOS:000172770100027 ER PT J AU Piat, M Torre, JP Beeman, JW Lamarre, JM Bhatia, RS AF Piat, M Torre, JP Beeman, JW Lamarre, JM Bhatia, RS TI Modelling and optimizing of high sensitivity semiconducting thermistors at low temperature SO JOURNAL OF LOW TEMPERATURE PHYSICS LA English DT Article ID THERMOMETERS; BOLOMETERS; GERMANIUM; SILICON; 20-MK AB We have modelled low temperature semiconducting thermometers by using a semi-analytical approach of Anderson insulators, taking into account both the electrical field and the electron/phonon decoupling effects. We first used this simulation to fit measured V(I) curves to validate this method and to obtain physical parameters of NTD Ge and NbSi thin film samples around 100 mK. We show that considering the two effects separately leads to an overestimate of each one. Once validated, our algorithm was used to optimise the design of high sensitivity thermometers for the High Frequency Instrument (HFI) of the Planck satellite. C1 Univ Paris 11, Inst Astrophys Spatiale, F-91405 Orsay, France. CNRS, Serv Aeron, F-91371 Verrieres Le Buisson, France. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. CALTECH, Pasadena, CA 91125 USA. RP Piat, M (reprint author), Univ Paris 11, Inst Astrophys Spatiale, Bat 121, F-91405 Orsay, France. NR 25 TC 3 Z9 3 U1 1 U2 3 PU KLUWER ACADEMIC/PLENUM PUBL 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 2001 VL 125 IS 5-6 BP 189 EP 203 DI 10.1023/A:1012911722522 PG 15 WC Physics, Applied; Physics, Condensed Matter SC Physics GA 510VM UT WOS:000173228000003 ER PT J AU Kanemitsu, Y Ando, M Matsuura, D Kushida, T White, CW AF Kanemitsu, Y Ando, M Matsuura, D Kushida, T White, CW TI Photo luminescence from CdS nanocrystals fabricated by sequential ion implantation SO JOURNAL OF LUMINESCENCE LA English DT Article; Proceedings Paper CT 30th International Conference on Dynamical Proces Excited States of Solids CY JUL 01-04, 2001 CL VILLEURBANNE, FRANCE DE CdS nanocrystal; free exciton; photoluminescence ID GAAS NANOCRYSTALS; MATRICES AB We have studied photoluminescence (PL) spectrum and dynamics of CdS nanocrystals fabricated by sequential Cd+ and S (+) ion implantation into Al2O3 matrices. Two peaks related to free excitons of hexagonal CdS are observed in the absorption spectrum at low temperatures, The broad and efficient PL band appears near the absorption edge. The spectral shape of the PL band depends on the excitation laser intensity. Our results show that the observed PL band consists of free-exciton emission and shallow-impurity emission. (C) 2001 Elsevier Science BN. All rights reserved. C1 Nara Inst Sci & Technol, Grad Sch Mat Sci, Nara 6300101, Japan. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Kanemitsu, Y (reprint author), Nara Inst Sci & Technol, Grad Sch Mat Sci, 8916-5 Takayama, Nara 6300101, Japan. NR 9 TC 9 Z9 9 U1 1 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-2313 J9 J LUMIN JI J. Lumines. PD DEC PY 2001 VL 94 BP 235 EP 238 DI 10.1016/S0022-2313(01)00285-X PG 4 WC Optics SC Optics GA 505ZD UT WOS:000172944700049 ER PT J AU Liu, GK Vikhnin, VS Zhuang, HZ Hong, KS Beitz, JV Antonio, MR Soderholm, L Williams, CW AF Liu, GK Vikhnin, VS Zhuang, HZ Hong, KS Beitz, JV Antonio, MR Soderholm, L Williams, CW TI Formation of UO2(BO3)(4) clusters in B2O3 glass due to charge transfer and vibronic effects SO JOURNAL OF LUMINESCENCE LA English DT Article; Proceedings Paper CT 13th International Conference on Dynamical Processes in Excited States of Solids CY JUL 01-04, 2001 CL Villeurbanne, FRANCE SP French Minist Educ, Reg Rhone Alpes, Dept Rhone, CNRS, Communaute Urbaine Lyon, Univ Claude Bernard Lyon, Alcatel Res & Innovat, Coherent SA, Spectra Phys Lasers, Papeteries JM Bruneau, Univ Joseph Fourier Grenoble DE uranyl cluster; charge transfer; vibronic effect ID PEROVSKITE-LIKE FERROELECTRICS; POLAR MICRODOMAINS; MULLER PHASE; EXCITONS; ORIGIN AB Laser-induced excitation and fluorescence spectra and X-ray absorption fine structure (EXAFS) of the U6+ L-3 edge (2p-5d) transitions indicate that uranyl ions in B2O3 glass have ordered local structure. Based on molecular dynamics (MD) simulation, four oxygen ions bind with each linear uranyl in the equatorial plane to form a stable crystalline UO6 cluster that binds with four groups of BO2. A charge transfer-lattice interaction model for the UO6 cluster formation in B2O3 glass is developed to explain the strong local lattice ordering and extraordinary stability of this cluster. The model is based on self-consistent oxygen-oxygen and oxygen-uranium charge transfer accompanied by lattice distortion both in the framework of pseudo-Jahn-Teller scheme. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. AF Ioffe Phys Tech Inst, St Petersburg 194021, Russia. RP Liu, GK (reprint author), Argonne Natl Lab, Div Chem, 9700 S Cass Ave, Argonne, IL 60439 USA. EM gkliu@anl.gov NR 7 TC 5 Z9 5 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-2313 J9 J LUMIN JI J. Lumines. PD DEC PY 2001 VL 94 BP 677 EP 681 DI 10.1016/S0022-2313(01)00394-5 PG 5 WC Optics SC Optics GA 505ZD UT WOS:000172944700138 ER PT J AU Vikhnin, VS Kaplyanskii, AA Kutsenko, AB Liu, GK Beitz, JV Kapphan, SE AF Vikhnin, VS Kaplyanskii, AA Kutsenko, AB Liu, GK Beitz, JV Kapphan, SE TI "Charge transfer-lattice" clusters induced by charged impurities SO JOURNAL OF LUMINESCENCE LA English DT Article; Proceedings Paper CT 13th International Conference on Dynamical Processes in Excited States of Solids CY JUL 01-04, 2001 CL Villeurbanne, FRANCE SP French Minist Educ, Reg Rhone Alpes, Dept Rhone, CNRS, Communaute Urbaine Lyon, Univ Claude Bernard Lyon, Alcatel Res & Innovat, Coherent SA, Spectra Phys Lasers, Papeteries JM Bruneau, Univ Joseph Fourier Grenoble DE charge transfer vibronic exciton; charged impurity; site conversion; multi-site structure ID TRANSFER VIBRONIC EXCITONS; PEROVSKITE-LIKE FERROELECTRICS; POLAR MICRODOMAINS; MULLER PHASE; ORIGIN AB A new type of self-consistent charge transfer-lattice states induced by charged impurities in their vicinity in ionic-covalent matrices are proposed and considered. A theory of these states is based on a charge transfer vibronic exciton (CTVE) model. The CTVE model explains the laser excitation-induced conversion of the sites accompanied by memory effect both caused by Eu3+ impurities in BaFCl crystal. The origin of this phenomenon connects with cross-relaxation between CTVE trapped by impurity, and excited states of this impurity. The CTVE model allows to propose a general mechanism of multi-site structure appearance induced by charged impurities in ionic-covalent solids. This mechanism is considered as an example of multi-site structure caused by RE3+ impurities in LiNbO3 crystal. (C) 2001 Published by Elsevier Science B.V. C1 AF Ioffe Phys Tech Inst, St Petersburg 194021, Russia. Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. Univ Osnabruck, Fachbereich Phys, D-49069 Osnabruck, Germany. RP AF Ioffe Phys Tech Inst, Politekhnicheskaya 26, St Petersburg 194021, Russia. EM valentin.vikhnin@physik.uni-osnabrueck.de RI Kaplyanskii, Alexander/E-4219-2014 NR 12 TC 14 Z9 14 U1 1 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-2313 EI 1872-7883 J9 J LUMIN JI J. Lumines. PD DEC PY 2001 VL 94 BP 775 EP 779 DI 10.1016/S0022-2313(01)00364-7 PG 5 WC Optics SC Optics GA 505ZD UT WOS:000172944700158 ER PT J AU Iwahara, J Wojciak, JM Clubb, RT AF Iwahara, J Wojciak, JM Clubb, RT TI An efficient NMR experiment for analyzing sugar-puckering in unlabeled DNA: Application to the 26-kDa dead ringer-DNA complex SO JOURNAL OF MAGNETIC RESONANCE LA English DT Article DE DNA; isotope filter; J modulation; protein-DNA complex; NMR; sugar pucker ID NUCLEIC-ACIDS; COUPLING-CONSTANTS; PROTEIN; FORMS AB We present a new NMR experiment for estimating the type and degree of sugar-puckering in high-molecular-weight unlabeled DNA molecules. The experiment consists of a NOESY sequence preceded by a constant-time scalar coupling period. Two subexperiments are compared, each differing in the amount of time the (3) J(H3'H2') and (3) J(H3'H2") couplings are active on the H3' magnetization. The resultant data are easy to analyze, since a comparison of the signal intensities of any resolved NOE cross peak originating from H3' atoms of the duplex can be used to estimate the sum of the (3) J(H3'H2') and 3 (JH3'H2') couplings and thus the puckering type of the deoxyribose ring. Isotope filters to eliminate signals of the C-13-labeled component in the F1-dimension are implemented, facilitating analyses of high-molecular-weight protein-DNA complexes containing C-13-labeled protein and unlabeled DNA. The utility of the experiment is demonstrated on the 26-kDa Dead Ringer protein-DNA complex and reveals that the DNA uniformly adopts the S-type configuration when bound to protein. (C) 2001 Elsevier Science. C1 Univ Calif Los Angeles, Dept Chem & Biochem, UCLA DOE Lab Struct Biol & Mol Med, Los Angeles, CA 90095 USA. RP Clubb, RT (reprint author), Univ Calif Los Angeles, Dept Chem & Biochem, UCLA DOE Lab Struct Biol & Mol Med, 405 Hilgard Ave, Los Angeles, CA 90095 USA. OI Iwahara, Junji/0000-0003-4732-2173 NR 23 TC 3 Z9 3 U1 0 U2 2 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 1090-7807 J9 J MAGN RESON JI J. Magn. Reson. PD DEC PY 2001 VL 153 IS 2 BP 262 EP 266 DI 10.1006/jmre.2001.2448 PG 5 WC Biochemical Research Methods; Physics, Atomic, Molecular & Chemical; Spectroscopy SC Biochemistry & Molecular Biology; Physics; Spectroscopy GA 511TV UT WOS:000173282400014 PM 11740904 ER PT J AU Quirke, JME Van Berkel, GJ AF Quirke, JME Van Berkel, GJ TI Electrospray tandem mass spectrometric study of alkyl 1-methylpyridinium ether derivatives of alcohols SO JOURNAL OF MASS SPECTROMETRY LA English DT Article DE electrospray mass spectrometry; alcohols; alkyl 1-methylpyridinium ethers; derivatization; tandem mass spectrometry; fragmentation mechanisms ID 4-AMINONAPHTHALENESULPHONIC ACID; IONIZATION; DERIVATIZATION; OLIGOSACCHARIDES; METABOLITES; PEPTIDES; REAGENTS; PHENOLS; ESTERS AB The fragmentation of 15 alkyl 1-methylpyridinium ether derivatives (D+) of primary and secondary alcohols, benzylic alcohols and phenyl-substituted alcohols was investigated using energy-resolved tandem mass spectrometry. Fragmentation pathways and mechanisms, including the influence of substituents, on the formation of the major product ions, which appear at m/z 110, [D - 109](+) and [D - 111](+), were postulated. Comparison of the abundances of these ions in the product ion spectra of isomeric alcohol derivatives, obtained at the same center-of-mass collision energy (2.0 eV), was found to provide the ability to differentiate among some isomers. Copyright (C) 2001 John Wiley Sons, Ltd. C1 Florida Int Univ, Dept Chem, Miami, FL 33199 USA. Oak Ridge Natl Lab, Div Chem Sci, Organ & Biol Mass Spectrometry Grp, Oak Ridge, TN 37831 USA. RP Quirke, JME (reprint author), Florida Int Univ, Dept Chem, Miami, FL 33199 USA. NR 30 TC 17 Z9 17 U1 1 U2 4 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 1076-5174 J9 J MASS SPECTROM JI J. Mass Spectrom. PD DEC PY 2001 VL 36 IS 12 BP 1294 EP 1300 DI 10.1002/jms.233 PG 7 WC Biophysics; Chemistry, Organic; Spectroscopy SC Biophysics; Chemistry; Spectroscopy GA 509AG UT WOS:000173121500006 PM 11754121 ER PT J AU Siegal, MP Dawley, JT Overmyer, DL AF Siegal, MP Dawley, JT Overmyer, DL TI Properties of YBa2Cu3O7-delta multilayer films from the fluoride-based sol-gel process SO JOURNAL OF MATERIALS RESEARCH LA English DT Article ID EPITAXIAL BA2YCU3O7-X FILMS; SUPERCONDUCTING THIN-FILMS; GROWTH; BAF2; PRESSURE; LAALO3; CU AB The inability to rapidly grow thick or multilayer epitaxial films for either electronic or electrical power applications limits the utility of fluoride-based processes for YBa2Cu3O7-delta (YBCO). This problem is due to the use of water vapor in the growth process, necessary for the dissociation of metallofluorides. Flowing wet gas at low temperatures is corrosive to cuprates and responsible for destroying underlying YBCO layers in attempts to grow secondary layers. This is avoided simply by increasing the temperature where vapor is introduced into the growth ambient. Resulting two-layer films of YBCO have properties similar to those of high critical current density single-layer films. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 18 TC 6 Z9 6 U1 0 U2 1 PU CAMBRIDGE UNIV PRESS PI NEW YORK PA 32 AVENUE OF THE AMERICAS, NEW YORK, NY 10013-2473 USA SN 0884-2914 EI 2044-5326 J9 J MATER RES JI J. Mater. Res. PD DEC PY 2001 VL 16 IS 12 BP 3339 EP 3342 DI 10.1557/JMR.2001.0459 PG 4 WC Materials Science, Multidisciplinary SC Materials Science GA 499RX UT WOS:000172585100003 ER PT J AU Chou, YS Kerstetter, K Pederson, LR Williford, RE AF Chou, YS Kerstetter, K Pederson, LR Williford, RE TI Mechanical and thermal properties of combustion-synthesized perovskites, La1-xSrxCr0.2Fe0.8O3 SO JOURNAL OF MATERIALS RESEARCH LA English DT Article ID MIXED-CONDUCTING PEROVSKITES; LANTHANUM CHROMITE; STABILITY; SOLIDS; SYSTEM; OXIDES; SR AB This paper examined the room-temperature thermal and mechanical properties of a mixed conducting perovskite La1-xSrxCr0.2Fe0.80O3 (x = 0.2 to 0.8). Powders were made by the combustion-synthesis technique and sintered at 1250 degreesC in air. Sintered density, crystal phase, and grain size were characterized. Linear thermal expansion in air was also tested. Young's and shear moduli, microhardness, indentation fracture toughness, and biaxial flexure strength were determined. It was found that the linear coefficient of thermal expansion increased with increasing Sr content, while elastic modulus appeared to decrease with increasing Sr content. Young's modulus of 128 to 192 GPa and shear modulus of 51 to 74 GPa were measured. A biaxial flexure strength of 243 MPa was measured for the lowest Sr content batches. Batches with higher Sr concentrations (x = 0.6 to 0.8) showed extensive cracking. Indentation toughness showed a decrease with increasing Sr content. In addition, fractography was used to characterize the critical flaw and the fracture mode. C1 Pacific NW Natl Lab, Dept Mat, Richland, WA 99352 USA. RP Chou, YS (reprint author), Pacific NW Natl Lab, Dept Mat, Richland, WA 99352 USA. RI pelosato, renato/E-9950-2010 NR 32 TC 4 Z9 4 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 2001 VL 16 IS 12 BP 3545 EP 3553 DI 10.1557/JMR.2001.0486 PG 9 WC Materials Science, Multidisciplinary SC Materials Science GA 499RX UT WOS:000172585100030 ER PT J AU Choi, YS Ahn, SH Kim, JG McKamey, CG AF Choi, YS Ahn, SH Kim, JG McKamey, CG TI Effect of chromium on the corrosion behavior of iron aluminides in thiosulfate-chloride solution SO JOURNAL OF MATERIALS SCIENCE LA English DT Article ID STAINLESS-STEEL; ALLOYS; SULFATE; FE3AL AB Aqueous corrosion characteristics of iron aluminides in thiosulfate-chloride solution were studied as a function of chromium addition. Four kinds of iron aluminides, namely, FA-61, FA-77, FA-72 and FA-78, were prepared by arc melting followed by thermomechanical treatment. The corrosion behavior in thiosulfate-chloride solution for the prepared alloys were investigated by electrochemical tests (potentiodynamic test, potentiostatic test and electrochemical impedance spectroscopy (EIS) measurement) and surface analyses. The results of the potentiodynamic test indicated that the breakdown potential increased with increasing Cr content. Cr additions were found to prevent passive film from undergoing pitting corrosion. In EIS measurement, the depression angle was inversely related to pitting resistance, and decreased with increasing chromium content. The SEM observations of the sample surfaces reveal the different forms of pit as a function of chromium content. The AES results give evidence that the thiosulfate ions are reduced on the metallic surface, which inhibits the repassivation process. (C) 2001 Kluwer Academic Publishers. C1 Sungkyunkwan Univ, Dept Adv Mat Engn, Suwon 440746, South Korea. Oak Ridge Natl Lab, Met & Ceram Div, Oak Ridge, TN 37831 USA. RP Choi, YS (reprint author), Sungkyunkwan Univ, Dept Adv Mat Engn, 300 Chunchun Dong, Suwon 440746, South Korea. EM kingo@chollian.net NR 15 TC 5 Z9 6 U1 1 U2 5 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 PY 2001 VL 36 IS 23 BP 5575 EP 5580 DI 10.1023/A:1012553329735 PG 6 WC Materials Science, Multidisciplinary SC Materials Science GA 489VD UT WOS:000172012400008 ER PT J AU Marks, RA Sugar, JD Glaeser, AM AF Marks, RA Sugar, JD Glaeser, AM TI Ceramic joining IV. effects of processing conditions on the properties of alumina joined via Cu/Nb/Cu interlayers SO JOURNAL OF MATERIALS SCIENCE LA English DT Review ID BONDED NB/AL2O3 INTERFACES; MOLECULAR-BEAM EPITAXY; TRANSIENT LIQUID; ELECTRON-MICROSCOPY; CU/AL2O3 INTERFACE; FRACTURE ENERGY; CU/ALPHA-AL2O3 INTERFACES; AL2O3(0001) SURFACE; SAPPHIRE INTERFACES; NB-AL2O3 INTERFACES AB Multilayer copper/niobium/copper interlayers consisting of 3 mum thick cladding layers of copper on a 125 mum thick niobium core layer were used to join aluminum oxides at 1150 degreesC or 1400 degreesC, or both. Three microstructurally distinct aluminum oxides were joined-a 25 mum grain size 99.5% pure alumina, a submicron grain size 99.9% pure alumina, and single crystal sapphire. Two-phase interlayer microstructures containing both copper-rich and niobium-rich phases developed during bonding. In some cases, the initially continuous copper film evolved via Rayleigh instabilities into an array of discrete copper-rich particles along the interlayer/alumina interface with concurrent increases in the niobium/alumina contact area. Processing conditions (temperature and applied load) and the alumina microstructure (grain size) impacted the extent of film breakup, the morphologies of the copper-rich and niobium-rich phases, the interlayer/alumina interfacial microstructure, and thereby the strength characteristics. Joints possessing a large copper/alumina interfacial area fraction were comparatively weak. Increases in bonding pressure and especially bonding temperature yielded interfaces with higher fractional niobium/alumina contact area. For joined polycrystals, such microstructures resulted in higher and more consistent room temperature fracture strengths. Joined 99.9% alumina polycrystals retained strengths > 200 MPa to 1200 degreesC. Relationships between processing conditions, interlayer and ceramic microstructure, and joint strength are discussed. (C) 2001 Kluwer Academic Publishers. C1 Univ Calif Berkeley, Dept Mat Sci & Engn, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Adv Mat, Berkeley, CA 94720 USA. RP Univ Calif Berkeley, Dept Mat Sci & Engn, Berkeley, CA 94720 USA. EM aglaeser@sapphire.berkeley.edu NR 102 TC 18 Z9 19 U1 0 U2 7 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0022-2461 EI 1573-4803 J9 J MATER SCI JI J. Mater. Sci. PD DEC PY 2001 VL 36 IS 23 BP 5609 EP 5624 DI 10.1023/A:1012565600601 PG 16 WC Materials Science, Multidisciplinary SC Materials Science GA 489VD UT WOS:000172012400014 ER PT J AU Abernathy, MC Mirsham, RA Raman, A Li, BQ Wereszczak, AA AF Abernathy, MC Mirsham, RA Raman, A Li, BQ Wereszczak, AA TI Simulation of the flow strength and microstructure of titanium aluminide in hot forging SO JOURNAL OF MATERIALS SCIENCE LA English DT Article ID ALLOY; DEFORMATION; RECRYSTALLIZATION; MODEL; WORKING AB The main purpose of this investigation is to develop a mathematical relationship for the flow strength based on microstructure evolution during the hot forming of titanium aluminide. For engineering applications, gamma titanium-aluminide which is composed of 46-50 at.% Al is desired in a duplex grain microstructure. Thermomechanical processing of this alloy requires a temperature of 0.60-0.75 T-M (melting point) in order to properly control the microstructure and grain growth. Compression tests were conducted in the temperature range between 950-1100 degreesC at strain rates of 0.001/s and 0.1/s to develop a duplex phase microstructure, gamma with 5-20% alpha (2). By using the experimental data, mathematical relationships were verified for different stages of hardening, recovery, recrystallization, and grain growth. The simulation was based on the theory used in the Sandstrom and Lagneborg model and the numerical analysis approach developed by Pietrzyk. The simulation proved that the model and numerical simulation well-presented the compression deformation of titanium-aluminide alloys at constant strain rates. (C) 2001 Kluwer Academic Publishers. C1 Louisiana State Univ, Dept Mech Engn, Baton Rouge, LA 70803 USA. So Univ, Dept Mech Engn, Baton Rouge, LA 70813 USA. Washington State Univ, Sch Mat & Mech, Pullman, WA 99164 USA. Oak Ridge Natl Lab, Oak Ridge, TN USA. RP Louisiana State Univ, Dept Mech Engn, Baton Rouge, LA 70803 USA. EM mirshams@unt.edu RI Wereszczak, Andrew/I-7310-2016 OI Wereszczak, Andrew/0000-0002-8344-092X NR 21 TC 3 Z9 3 U1 0 U2 3 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0022-2461 EI 1573-4803 J9 J MATER SCI JI J. Mater. Sci. PD DEC PY 2001 VL 36 IS 23 BP 5697 EP 5704 DI 10.1023/A:1012538321074 PG 8 WC Materials Science, Multidisciplinary SC Materials Science GA 489VD UT WOS:000172012400023 ER PT J AU Chrysostom, ETH Vulpanovici, N Masiello, T Barber, J Nibler, JW Weber, A Maki, A Blake, TA AF Chrysostom, ETH Vulpanovici, N Masiello, T Barber, J Nibler, JW Weber, A Maki, A Blake, TA TI Coherent Raman and infrared studies of sulfur trioxide SO JOURNAL OF MOLECULAR SPECTROSCOPY LA English DT Article DE Raman; coherent Raman; CARS; infrared; spectrum; sulfur trioxide ID SYMMETRIC TOP MOLECULES; HIGH-RESOLUTION; FORCE-FIELD; SO3; BAND; CONSTANTS; SPECTRUM; (SO2)-S-32-O-16; SPECTROSCOPY AB High-resolution (0.001 cm(-1)) coherent anti-Stokes Raman scattering (CARS) was used to observe the Q-branch structure of the IR-inactive nu(1) symmetric stretching mode of (SO3)-S-32-O-16 and its various O-18 isotopomers. The nu(1) spectrum of (SO3)-S-32-O-16 reveals two intense Q-branches in the region 1065-1067 cm-1, with surprisingly complex vibrational-rotational structure not resolved in earlier studies. Efforts to simulate this with a simple Fermi-resonance model involving nu(1) and 2nu(4) states do not reproduce the spectral detail, nor do they yield reasonable spectroscopic parameters. A more subtle combination of Fermi resonance and indirect Coriolis interactions with nearby states, 2nu(4) (1 = 0, +/-2), nu(2) + nu(4) (1 = +/-1) 2nu(2) (1 = 0), is suspected and a determination of the location of these coupled states by high-resolution infrared measurements is under way. At medium resolution (0.125 cm(-1)), the infrared spectra reveal Q-branch features from which approximate band origins are estimated for the nu(2), nu(3), and nu(4) fundamental modes of (SO3)-S-32-O-18, (SO2O)-S-32-O-18-O-16, and (SOO2)-S-32-O-18-O-16. These and literature data for (SO3)-S-32-O-16 are used to calculate force constants for SO3 and a comparison is made with similar values for SO2 and SO. The frequencies and force constants are in excellent agreement with those obtained by Martin in a recent ab initio calculation. (C) 2001 Elsevier Science. C1 Oregon State Univ, Dept Chem, Corvallis, OR 97331 USA. Natl Sci Fdn, Arlington, VA 22230 USA. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Pacific NW Natl Lab, Richland, WA 99352 USA. RP Nibler, JW (reprint author), Oregon State Univ, Dept Chem, Corvallis, OR 97331 USA. NR 50 TC 17 Z9 17 U1 0 U2 12 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 2001 VL 210 IS 2 BP 233 EP 239 DI 10.1006/jmsp.2001.8463 PG 7 WC Physics, Atomic, Molecular & Chemical; Spectroscopy SC Physics; Spectroscopy GA 517MC UT WOS:000173613500008 ER PT J AU Maki, A Blake, TA Sams, RL Vulpanovici, N Barber, J Chrysostom, ETH Masiello, T Nibler, JW Weber, A AF Maki, A Blake, TA Sams, RL Vulpanovici, N Barber, J Chrysostom, ETH Masiello, T Nibler, JW Weber, A TI High-resolution infrared spectra of the nu 2, nu 3, nu 4, and 2 nu(3) bands of (SO3)-S-32-O-16 SO JOURNAL OF MOLECULAR SPECTROSCOPY LA English DT Article DE infrared; spectrum; sulfur trioxide ID FOURIER-TRANSFORM; SULFUR-TRIOXIDE; SO3; V2 AB New measurements are reported for the infrared spectrum of sulfur trioxide, (SO3)-S-32-O-16, with resolutions ranging from 0.0015 cm(-1) to 0.0025 cm(-1). Rovibrational constants have been measured for the fundamentals nu(2), nu(3), and nu(4) and the overtone band 2nu(3). Comparisons are made with the earlier high-resolution measurements on SO3, and the high correlation among some of the constants related to the Coriolis coupling of the nu(2) and nu(4) levels is discussed in order to understand the areas of disagreement with the earlier work, Splittings of some of the levels are observed and the splitting constant for K = 3 of the ground state is determined for the first time. Other observed splittings include the K = 1 levels of 2nu(3) (l = 2), the K = 2 levels of nu(3) and nu(4), and the K = 3 levels of nu(2). The analysis shows that there are level crossings between the l = 0 and l = 2 states of 2nu(3) that allow one to determine the separation of the subband centers for these two states even though access to the l = 0 state from the ground state is electric-dipole forbidden. This is a generalized phenomenon that should be found for many other molecules with the same symmetry. The l-type resonance constant, q(3), that causes the splitting of the l(3) = +/-1, k = +/-1 levels of nu(3) also couples the l(3) = 0 and 2 states of 2nu(3). (C) 2001 Elsevier Science. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. Oregon State Univ, Dept Chem, Corvallis, OR 97331 USA. Natl Sci Fdn, Arlington, VA 22230 USA. Natl Inst Stand & Technol, Opt Technol Div, Gaithersburg, MD 20899 USA. RP Maki, A (reprint author), 15012 24th Ave SE, Mill Creek, WA 98012 USA. NR 13 TC 26 Z9 26 U1 1 U2 6 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 2001 VL 210 IS 2 BP 240 EP 249 DI 10.1006/jmsp.2001.8454 PG 10 WC Physics, Atomic, Molecular & Chemical; Spectroscopy SC Physics; Spectroscopy GA 517MC UT WOS:000173613500009 ER PT J AU Fowler, JS Logan, J Ding, YS Franceschi, D Wang, GJ Volkow, ND Pappas, N Schlyer, D Gatley, SJ Alexoff, D Felder, C Biegon, A Zhu, W AF Fowler, JS Logan, J Ding, YS Franceschi, D Wang, GJ Volkow, ND Pappas, N Schlyer, D Gatley, SJ Alexoff, D Felder, C Biegon, A Zhu, W TI Non-MAO A binding of clorgyline in white matter in human brain SO JOURNAL OF NEUROCHEMISTRY LA English DT Article DE clorgyline; human brain; monoamine oxidase A; white matter ID MONOAMINE-OXIDASE-A; POSITRON EMISSION TOMOGRAPHY; C-11 L-DEPRENYL; INHIBITION; PET; LIGAND; MODEL AB Clorgyline is an irreversible inhibitor of monoamine oxidase (MAO A) which has been labeled with carbon-11 (C-11) and used to measure human brain MAO A with positron emission tomography (PET). In this study we compared [C-11]clorgyline and deuterium-substituted [C-11]clorgyline ([C-11]clorgyline-D2) to better understand the molecular link between [C-11]clorgyline binding and MAO A. In PET studies of five normal healthy volunteers scanned with [C-11]clorgyline and [C-11]clorgyline-D2 2 h apart, deuterium substitution generally produced the expected reductions in the brain uptake of [C-11]clorgyline. However, the reduction was not uniform with the C-11 binding in white matter being significantly less sensitive to deuterium substitution than other brain regions. The percentages of the total binding attributable to MAO A is largest for the thalamus and smallest for the white matter and this is clearly seen in PET images with [C-11]clorgyline-D2. Thus deuterium-substituted [C-11]clorgyline selectively reduces the MAO A binding component of clorgyline in the human brain revealing non-MAO A binding which is most apparent in the white matter. The characterization of the non-MAO A binding component of this widely used MAO A inhibitor merits further investigation. C1 Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. SUNY Stony Brook, Dept Appl Math & Stat, Stony Brook, NY 11794 USA. RP Fowler, JS (reprint author), Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. FU NINDS NIH HHS [NS 15380] NR 28 TC 22 Z9 22 U1 0 U2 4 PU BLACKWELL SCIENCE LTD PI OXFORD PA P O BOX 88, OSNEY MEAD, OXFORD OX2 0NE, OXON, ENGLAND SN 0022-3042 J9 J NEUROCHEM JI J. Neurochem. PD DEC PY 2001 VL 79 IS 5 BP 1039 EP 1046 DI 10.1046/j.1471-4159.2001.00649.x PG 8 WC Biochemistry & Molecular Biology; Neurosciences SC Biochemistry & Molecular Biology; Neurosciences & Neurology GA 499BX UT WOS:000172552100015 PM 11739617 ER PT J AU Volkow, ND Chang, L Wang, GJ Fowler, JS Franceschi, D Sedler, M Gatley, SJ Miller, E Hitzemann, R Ding, YS Logan, J AF Volkow, ND Chang, L Wang, GJ Fowler, JS Franceschi, D Sedler, M Gatley, SJ Miller, E Hitzemann, R Ding, YS Logan, J TI Loss of dopamine transporters in methamphetamine abusers recovers with protracted abstinence SO JOURNAL OF NEUROSCIENCE LA English DT Article DE methamphetamine; dopamine transporters; imaging; positron emission tomography; addiction; detoxification; neurotoxicity; dopamine terminal ID POSITRON-EMISSION-TOMOGRAPHY; BRAIN; PET; INTERNALIZATION; NEUROTOXICITY; HYDROXYLASE; CONTRAST; DISEASE; BINDING; MONKEYS AB Methamphetamine is a popular drug of abuse that is neurotoxic to dopamine (DA) terminals when administered to laboratory animals. Studies in methamphetamine abusers have also documented significant loss of DA transporters (used as markers of the DA terminal) that are associated with slower motor function and decreased memory. The extent to which the loss of DA transporters predisposes methamphetamine abusers to neurodegenerative disorders such as Parkinsonism is unclear and may depend in part on the degree of recovery. Here we assessed the effects of protracted abstinence on the loss of DA transporters in striatum, in methamphetamine abusers using positron emission tomography and [C-11]d-threo-methylphenidate (DA transporter radioligand). Brain DA transporters in five methamphetamine abusers evaluated during short abstinence (<6 months) and then retested during protracted abstinence (12-17 months) showed significant increases with protracted abstinence (caudate, +19%; putamen, +16%). Although performance in some of the tests for which we observed an association with DA transporters showed some improvement, this effect was not significant. The DA transporter increases with abstinence could indicate that methamphetamine-induced DA transporter loss reflects temporary adaptive changes (i.e., downregulation), that the loss reflects DA terminal damage but that terminals can recover, or that remaining viable terminals increase synaptic arborization. Because neuropsychological tests did not improve to the same extent, this suggests that the increase of the DA transporters was not sufficient for complete function recovery. These findings have treatment implications because they suggest that protracted abstinence may reverse some of methamphetamine-induced alterations in brain DA terminals. C1 Brookhaven Natl Lab, Dept Med, Upton, NY 11973 USA. Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. SUNY Stony Brook, Dept Psychiat, Stony Brook, NY 11794 USA. Univ Calif Los Angeles, Los Angeles Cty Harbor Med Ctr, Dept Psychiat, Torrance, CA 90502 USA. RP Volkow, ND (reprint author), Brookhaven Natl Lab, Dept Med, Upton, NY 11973 USA. FU NCRR NIH HHS [MO1 RR10710, MO1RR 00425]; NIDA NIH HHS [DA00280, DA06891, DA7092-01] NR 27 TC 336 Z9 344 U1 3 U2 29 PU SOC NEUROSCIENCE PI WASHINGTON PA 11 DUPONT CIRCLE, NW, STE 500, WASHINGTON, DC 20036 USA SN 0270-6474 J9 J NEUROSCI JI J. Neurosci. PD DEC 1 PY 2001 VL 21 IS 23 BP 9414 EP 9418 PG 5 WC Neurosciences SC Neurosciences & Neurology GA 494BL UT WOS:000172258400037 PM 11717374 ER PT J AU McGrail, BP Icenhower, JP Shuh, DK Liu, P Darab, JG Baer, DR Thevuthasen, S Shutthanandan, V Engelhard, MH Booth, CH Nachimuthu, P AF McGrail, BP Icenhower, JP Shuh, DK Liu, P Darab, JG Baer, DR Thevuthasen, S Shutthanandan, V Engelhard, MH Booth, CH Nachimuthu, P TI The structure of Na2O-Al2O3-SiO2 glass: impact on sodium ion exchange in H2O and D2O SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article ID ABSORPTION FINE-STRUCTURE; SILICATE-GLASSES; ALUMINOSILICATE GLASSES; WASTE GLASS; SURFACE; DISSOLUTION; MINERALS; RATES; EXAFS; NMR AB The kinetics of matrix dissolution and alkali-exchange for a series of sodium aluminosilicate glass compositions was determined at constant temperature and solution pH(D) under conditions of silica-saturation. Steady state release rate for sodium was 10-50 times faster than the rate of matrix dissolution, demonstrating that alkali exchange is an important long-term reaction mechanism that must be considered when modeling systems near saturation with respect to dissolved glass components. Sodium release rates were 30% slower in D2O compared to rates in H2O; but matrix dissolution rates were unaffected. These results are consistent with rupture of the O-H bond as the rate-limiting reaction in Na+-H+ exchange whereas matrix dissolution is controlled by OH- or H2O catalyzed hydrolysis of Si-O-Si and Si-O-Al bonds. Changes in Na exchange rate with increasing Al2O3 content could not be reconciled with changes in the number of non-bridging oxygen (NBO) sites in the glass alone. A simple model was used to estimate a structural energy barrier for alkali ion exchange using Na-O bond length and co-ordination as measured by Na K-edge X-ray absorption spectroscopy, and binding energy shifts for Si-O-Na sites measured by X-ray photoelectron spectroscopy (XPS). The energy barrier was calculated to increase from 34 kJ mol-(1) for Na2O. 2SiO(2) glass to 49 kJ mol(-1) for a glass containing 15 mol% Al2O3, consistent with stronger bonding of Na on NBO sites and increasing mechanical stiffness of the glass network with increasing Al content. The calculated ion-exchange enthalpies were then used to calculate Na ion-exchange rates as a function of glass composition. Agreement between the calculated and measured Na ion exchange rates was excellent. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Pacific NW Natl Lab, Appl Geol & Geochem Grp, Richland, WA 99352 USA. Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. Univ Nevada, Dept Chem, Las Vegas, NV 89154 USA. RP Pacific NW Natl Lab, Appl Geol & Geochem Grp, MSIN K6-81, Richland, WA 99352 USA. EM pete.mcgrail@pnl.gov RI Engelhard, Mark/F-1317-2010; Icenhower, Jonathan/E-8523-2011; Booth, Corwin/A-7877-2008; Baer, Donald/J-6191-2013; OI Baer, Donald/0000-0003-0875-5961; Engelhard, Mark/0000-0002-5543-0812 NR 56 TC 82 Z9 83 U1 6 U2 46 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3093 EI 1873-4812 J9 J NON-CRYST SOLIDS JI J. Non-Cryst. Solids PD DEC PY 2001 VL 296 IS 1-2 BP 10 EP 26 DI 10.1016/S0022-3093(01)00890-0 PG 17 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA 496TB UT WOS:000172411600002 ER PT J AU Zhang, YH Navrotsky, A Li, H Li, LY Davis, LL Strachan, DM AF Zhang, YH Navrotsky, A Li, H Li, LY Davis, LL Strachan, DM TI Energetics of dissolution of Gd2O3 and HfO2 in sodium alumino-borosilicate glasses SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article ID HIGH-TEMPERATURE CALORIMETRY; COOPERATIVE LUMINESCENCE; THERMOCHEMISTRY; SOLUBILITY; DISPOSITION; DIRECTIONS; PROGRESS; FORMS; IONS AB In addition to their industrial and consumer-oriented applications, sodium alumino-borosilicate glasses are leading candidates for encapsulation of reprocessed commercial and defense-related nuclear waste. Quantification of the thermochemical and physical properties of these glasses is necessary for a complete understanding of processes occurring in these systems. In this study, 16 glass samples were studied including the base glass (20Na(2)O-15B(2)O(3)-5Al(2)O(3)-60SiO(2)), six Gd-doped glasses (0.45, 0.92, 1.72, 3.25, 4.74, 7.67, 10.53 mol% Gd2O3) and eight Hf-doped glasses (0.15, 0.38, 0.77, 1.57, 3.27, 5.09, 7.06, 11.53 mol% HfO2). Drop solution calorimetry using lead borate solvent at 976 K indicates that these glasses are energetically stable with respect to their binary crystalline oxides. There is a sharp change in the enthalpy of formation between glasses with more than 1.6 mol% Gd2O3 or HfO2 addition and glasses of lower Gd2O3 or HfO2 content. At higher doping levels, the apparent partial molar enthalpy of solution of HfO2 in the glass is close to zero, consistent with the formation of nanometer-sized heterogeneities. A possible explanation is that glasses with more than 1.6 mol% added oxides consist of regions of Gd2O3 or HfO2-rich glass perhaps containing regions of medium-range order dominated by Gd2O3 or HfO2 and/or their nanocrystals and regions of Gd2O3 or HfO2 poor glass. Glass transition temperatures from DSC experiments indicate similar trends with a change in slope near 1.6 mol% Gd2O3 or HfO2. These data are consistent with structural and spectroscopic studies that suggest the onset of clustering and related changes in structure in this composition range. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Calif Davis, Dept Chem Engn & Mat Sci, Thermochem Facil, Davis, CA 95616 USA. Pacific NW Natl Lab, Richland, WA 99352 USA. RP Univ Calif Davis, Dept Chem Engn & Mat Sci, Thermochem Facil, Davis, CA 95616 USA. EM anavrotsky@ucdavis.edu NR 30 TC 30 Z9 30 U1 1 U2 8 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3093 EI 1873-4812 J9 J NON-CRYST SOLIDS JI J. Non-Cryst. Solids PD DEC PY 2001 VL 296 IS 1-2 BP 93 EP 101 DI 10.1016/S0022-3093(01)00876-6 PG 9 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA 496TB UT WOS:000172411600011 ER PT J AU Carbajo, JJ Yoder, GL Popov, SG Ivanov, VK AF Carbajo, JJ Yoder, GL Popov, SG Ivanov, VK TI A review of the thermophysical properties of MOX and UO2 fuels SO JOURNAL OF NUCLEAR MATERIALS LA English DT Review ID THERMAL-CONDUCTIVITY; URANIUM-DIOXIDE; HEAT-CAPACITY; OXIDE FUELS; MIXED-OXIDE; THERMODYNAMIC PROPERTIES; TEMPERATURE; TRANSITION; SIMFUEL; (U AB A critical review of the thermophysical properties Of UO2 and MOX fuels has been completed, and the best correlations for thermophysical properties have been selected. The properties reviewed are solidus and liquidus temperatures of the uranium/plutonium dioxide system (melting and solidification temperatures), thermal expansion and density, enthalpy and specific heat, enthalpy (or heat) of fusion, and thermal conductivity. Only fuel properties have been reviewed. The selected set of property correlations was compiled to be used in thermal-hydraulic codes to perform safety calculations. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. IV Kurchatov Atom Energy Inst, Inst Nucl Reactors, Russian Res Ctr, Moscow 123182, Russia. RP Carbajo, JJ (reprint author), Oak Ridge Natl Lab, POB 2009, Oak Ridge, TN 37831 USA. NR 61 TC 108 Z9 113 U1 23 U2 102 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 2001 VL 299 IS 3 BP 181 EP 198 DI 10.1016/S0022-3115(01)00692-4 PG 18 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 516HL UT WOS:000173547800001 ER PT J AU Singh, BN Edwards, DJ Toft, P AF Singh, BN Edwards, DJ Toft, P TI Effect of neutron irradiation and post-irradiation annealing on microstructure and mechanical properties of OFHC-copper SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article ID CASCADE DAMAGE CONDITIONS; DISLOCATION LOOPS; BCC METALS; ALLOYS AB Specimens of oxygen-free high conductivity (OFHC) copper were irradiated in the DR-3 reactor at Riso at 100 degreesC to doses in the range 0.01-0.3 dpa (NRT). Some of the specimens were tensile tested in the as-irradiated condition at 100 degreesC whereas others were given a post-irradiation annealing treatment at 300 degreesC for 50 h and subsequently tested at 100 degreesC. The microstructure of specimens was characterized in the as-irradiated as well as irradiated and annealed conditions both before and after tensile deformation. While the interstitial loop microstructure coarsens with irradiation dose, no significant changes were observed in the population of stacking fault tetrahedra (SFT). The post-irradiation annealing leads to only a partial recovery and the level of recovery depends on the irradiation dose level. However, the postirradiation annealing eliminates the yield drop and reinstates enough uniform elongation to render the material useful again. These results are discussed in terms of the cascade-induced source hardening (CISH) model. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Riso Natl Lab, Mat Res Dept, DK-4000 Roskilde, Denmark. Pacific NW Natl Lab, Struct Mat Dev, Richland, WA 99352 USA. RP Singh, BN (reprint author), Riso Natl Lab, Mat Res Dept, DK-4000 Roskilde, Denmark. NR 22 TC 49 Z9 50 U1 8 U2 22 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 2001 VL 299 IS 3 BP 205 EP 218 DI 10.1016/S0022-3115(01)00698-5 PG 14 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 516HL UT WOS:000173547800003 ER PT J AU Groch, MW DePuey, EG Belzberg, AC Erwin, WD Kamran, M Barnett, CA Hendel, RC Spies, SM Ali, A Marshall, RC AF Groch, MW DePuey, EG Belzberg, AC Erwin, WD Kamran, M Barnett, CA Hendel, RC Spies, SM Ali, A Marshall, RC TI Planar imaging versus gated blood-pool SPECT for the assessment of ventricular performance: A multicenter study SO JOURNAL OF NUCLEAR MEDICINE LA English DT Article; Proceedings Paper CT 73rd Scientific Sessions of the American-Heart-Association CY NOV 12-15, 2000 CL NEW ORLEANS, LOUISIANA SP Amer Heart Assoc DE gated blood-pool imaging; gated SPECT; left ventricular ejection fraction ID EMISSION COMPUTED-TOMOGRAPHY; CORONARY-ARTERY DISEASE; EJECTION FRACTION; RADIONUCLIDE ANGIOGRAPHY; MYOCARDIAL PERFUSION; WALL MOTION; QUANTIFICATION; VOLUMES AB Gated blood-pool SPELT (GBPS), inherently 3-dimensional (3D), has the potential to replace planar equilibrium radionuclide angiography (ERNA) for computation of left ventricular ejection fraction (LVEF), analysis of regional wall motion (RWM), and analysis of right heart function. The purpose of this study was to compare GBPS and ERNA for the assessment of ventricular function in a large, multicenter cohort of patients. Methods: One hundred seventy-eight patients referred in the usual manner for nuclear medicine studies underwent ERNA followed by GBPS. Each clinical site followed a GBPS acquisition protocol that included 180 degrees rotation, a 64 by 64 matrix, and 64 or 32 views using single- or double-head cameras. Transverse GBPS images were reconstructed with a Butterworth filter (cutoff frequency, 0.45-0.55 Nyquist; order, 7), and short-axis images were created. All GBPS studies were processed with a new GBPS program, and LVEF was computed from the isolated left ventricular chamber and compared with standard ERNA LVEF. Reproducibility of GBPS LVEF was evaluated, and right ventricular ejection fraction (RVEF) was computed in a subset of patients (n = 33). Using GBPS, RWM and image quality from 3D surface-shaded and volume-rendered cine displays were evaluated qualitatively in a subset of patients (n = 30). Results: The correlation between GBPS LVEF and planar LVEF was excellent (r = 0.92). Mean LVEF was 62.2% for GBPS and 54.1% for ERNA. The line of linear regression was GBPS LVEF = (1.04 x ERNA LVEF) + 6.1. Bland-Altman plotting revealed an increasing bias in GBPS LVEF with increasing LVEF (Y = 0.13x + 0.61; r = 0.30; mean difference = 8.1% +/- 7.0%). Interoperator reproducibility of GBPS LVEF was good (r = 0.92). RVEF values averaged 59.8%. RWM assessment using 3D cine display was enhanced in 27% of the studies, equivalent in 67%, and inferior in 7%. Conclusion: GBPS LVEF was reproducible and correlated well with planar ERNA. GBPS LVEF values were somewhat higher than planar ERNA, likely because of the exclusion of the left atrium. C1 Northwestern Univ, Sch Med, Chicago, IL USA. Rush Presbyterian St Lukes Med Ctr, Chicago, IL 60612 USA. Rush Univ, Chicago, IL 60612 USA. St Lukes Roosevelt Hosp, New York, NY 10025 USA. Columbia Univ, New York, NY USA. St Pauls Hosp, Vancouver, BC V6Z 1Y6, Canada. Univ British Columbia, Vancouver, BC V5Z 1M9, Canada. Vet Affairs Med Ctr, Martinez, CA USA. Univ Calif Davis, Davis, CA 95616 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Groch, MW (reprint author), NW Mem Hosp, Dept Nucl Med, 251 E Huron St, Chicago, IL 60611 USA. NR 18 TC 40 Z9 40 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD DEC PY 2001 VL 42 IS 12 BP 1773 EP 1779 PG 7 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 504DZ UT WOS:000172843200017 PM 11752072 ER PT J AU Dai, D Tang, J Rose, R Hodgson, E Bienstock, RJ Mohrenweiser, HW Goldstein, JA AF Dai, D Tang, J Rose, R Hodgson, E Bienstock, RJ Mohrenweiser, HW Goldstein, JA TI Identification of variants of CYP3A4 and characterization of their abilities to metabolize testosterone and chlorpyrifos SO JOURNAL OF PHARMACOLOGY AND EXPERIMENTAL THERAPEUTICS LA English DT Article ID ADULT HUMAN-LIVER; AMINO-ACID; GENETIC VARIANT; CLINICAL PRESENTATION; CYTOCHROME-P450 3A4; PROSTATE TUMORS; SMALL-BOWEL; BIOTRANSFORMATION; SUBSTITUTIONS; POLYMORPHISM AB CYP3A4 is the most abundant isoform of cytochrome P450 (CYP) in adult human liver. It metabolizes numerous clinically, physiologically, and toxicologically important compounds. The expression of CYP3A4 varies 40-fold in individual human livers, and metabolism of CYP3A4 substrates varies at least 10-fold in vivo. Single nucleotide polymorphisms (SNPs) in CYP3A4 were identified by direct sequencing of genomic DNA in 72 individuals from three different ethnic groups, including Caucasians, Blacks (African-Americans and African pygmies), and Asians. A total of 28 SNPs were identified, including five which produced coding changes M445T (CYP3A4*3), R162Q (CYP3A4*15), F189S (CYP3A4*17), L293P (CYP3A4*18), and P467S (CYP3A4*19). The latter four represent new alleic variants. Racial variability was observed for the frequency of individual SNPs. CYP3A R162Q was identified only in Black populations with an allelic frequency of 4%. CYP3A4 F189S and CYP3A4 M445T were identified in Caucasians with allelic frequencies 2% and 4%, respectively. L293P and P467S were only observed in Asians at allelic frequencies of 2%. The cDNAs for the F189S, L293P, M445T, and P467S mutant alleles were constructed by site-directed mutagenesis and expressed in an Escherichia coli expression system. Testosterone and the insecticide chlorpyrifos were used to assess the catalytic activities of the most common CYP3A4 allele (CYP3A4*1) and its allelic variants. CYP3A4 F189S exhibited lower turnover numbers for testosterone and chlorpyrifos, while CYP3A4 L293P had higher turnover numbers for both substrates. The turnover numbers of the CYP3A4 M445T and P467S alleles to metabolize these compounds were not significantly different from those of wild-type CYP3A4. C1 NIEHS, Lab Pharmacol & Chem, NIH, Res Triangle Pk, NC 27709 USA. N Carolina State Univ, Dept Toxicol, Raleigh, NC 27695 USA. Lawrence Livermore Natl Lab, Livermore, CA USA. RP Goldstein, JA (reprint author), NIEHS, Lab Pharmacol & Chem, NIH, POB 12233, Res Triangle Pk, NC 27709 USA. RI Goldstein, Joyce/A-6681-2012 FU NIEHS NIH HHS [Y1-ES-8054-05] NR 41 TC 224 Z9 252 U1 2 U2 7 PU AMER SOC PHARMACOLOGY EXPERIMENTAL THERAPEUTICS PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0022-3565 J9 J PHARMACOL EXP THER JI J. Pharmacol. Exp. Ther. PD DEC PY 2001 VL 299 IS 3 BP 825 EP 831 PG 7 WC Pharmacology & Pharmacy SC Pharmacology & Pharmacy GA 497YY UT WOS:000172484100003 PM 11714865 ER PT J AU Hinchliffe, I Richardson, P AF Hinchliffe, I Richardson, P TI Supersymmetric models and collider signatures SO JOURNAL OF PHYSICS G-NUCLEAR AND PARTICLE PHYSICS LA English DT Article ID GRAND UNIFICATION; ENERGY; BREAKING; SUPERGRAVITY; TRILEPTON; TEVATRON AB We briefly review the SUGRA, GMSB and AMSB supersymmetry breaking models. We then discuss the phenomenological differences between them and consequent characteristic experimental signatures. This is followed by a review of the discovery potential for supersymmetry at the Tevatron, LHC and a future e(+)e(-) linear collider. C1 Lawrence Berkeley Natl Lab, Berkeley, CA USA. Univ Cambridge, Cavendish Lab, Cambridge CB3 0HE, England. DAMTP, Ctr Math Sci, Cambridge, England. RP Hinchliffe, I (reprint author), Lawrence Berkeley Natl Lab, Berkeley, CA USA. OI Richardson, Peter/0000-0002-3349-345X NR 32 TC 0 Z9 0 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0954-3899 J9 J PHYS G NUCL PARTIC JI J. Phys. G-Nucl. Part. Phys. PD DEC PY 2001 VL 27 IS 12 BP 2485 EP 2496 DI 10.1088/0954-3899/27/12/310 PG 12 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 504ZU UT WOS:000172886900011 ER PT J AU Di Lorenzo, ML Pyda, M Wunderlich, B AF Di Lorenzo, ML Pyda, M Wunderlich, B TI Reversible melting in nanophase-separated poly (oligoamide-alt-oligoether)s and its dependence on sequence length, crystal perfection, and molecular mobility SO JOURNAL OF POLYMER SCIENCE PART B-POLYMER PHYSICS LA English DT Article DE temperature-modulated calorimetry; reversible melting; block copolymers; nylon-12; poly(oxytetramethylene); molecular nucleation; poly(oligoamide-alt-oligoether) ID TEMPERATURE-MODULATED CALORIMETRY; DIFFERENTIAL SCANNING CALORIMETRY; X-RAY-SCATTERING; THERMODYNAMIC PROPERTIES; ALIPHATIC NYLONS; HEAT-CAPACITY; CRYSTALLIZATION; POLYETHYLENE; MODEL; TEREPHTHALATE) AB The degree of reversibility of the melting of multiblock copolymers of alternating oligoamides and oligoethers was investigated with respect to the composition and molecular mass of the blocks. The analysis was conducted with temperature-modulated calorimetry, and it revealed different degrees of reversibility of the melting process that depended on the block length, crystal perfection, and molecular mobility. For the oligoamide blocks, the amount of crystal that melts and crystallizes reversibly during quasi-isothermal analysis increases with decreasing molar mass, and shorter amide sequences form poorer crystals that have a higher tendency toward reorganization. Reorganization of the oligoamides is also favored by the presence of the more mobile oligoether units. Reversible melting of the oligoether segments is influenced by the presence of glassy and crystalline oligoamide blocks in the adjacent nanophases. Because of the segmented nature of the copolymers, the oligoether segments are not free to flow as in an isotropic melt but are anchored to the oligoamide surfaces with different degrees of restriction that change the local equilibrium of melting and recrystallization. A comparison of the copolymers with the corresponding homopolymers provides information about the role of molecular nucleation and mobility in the reversibility of melting. (C) 2001 John Wiley & Sons, Inc.*. C1 Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. Comprensorio Olivetti, CNR, Ist Ric & Tecnol Mat Plast, I-80078 Pozzuoli, NA, Italy. 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. RI Di Lorenzo, Maria Laura/N-5692-2015 NR 44 TC 22 Z9 22 U1 0 U2 9 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0887-6266 J9 J POLYM SCI POL PHYS JI J. Polym. Sci. Pt. B-Polym. Phys. PD DEC 1 PY 2001 VL 39 IS 23 BP 2969 EP 2981 DI 10.1002/polb.10059 PG 13 WC Polymer Science SC Polymer Science GA 492EG UT WOS:000172155000005 ER PT J AU Pyda, M AF Pyda, M TI Conformational contribution to the heat capacity of the starch and water system SO JOURNAL OF POLYMER SCIENCE PART B-POLYMER PHYSICS LA English DT Article DE heat capacity; glass transition; starch; starch-water; vibration; conformation; thermal properties ID CARBON BACKBONE POLYMERS; LINEAR MACROMOLECULES; THERMODYNAMIC PROPERTIES; POLY(AMINO ACID)S; FLUCTUATIONS; CALORIMETRY; COMPUTATION; PROTEINS AB The heat capacities of starch and starch-water have been measured with adiabatic calorimetry and standard differential scanning calorimetry and are reported from 8 to 490 K. The amorphous starch containing 11-26 wt % (53-76 mol %) water shows a partial glass transition decreasing from 372 to 270 K, respectively. Even the dry amorphous starch gradually increases in heat capacity above 270 K beyond that set by the vibrational density of states. This gradual increase in the heat capacity is identified as part of the glass transition of dry starch that is, however, not completed at the decomposition temperature. The heat capacities of the glassy, dry starch are linked to an approximate group vibrational spectrum with 44 degrees of freedom. The Tarasov equation is used to estimate the heat capacity contribution due to skeletal vibrations with the parameters Theta (1) = 795.5 K, Theta (2) = 159 K, and Theta (3) = 58 K for 19 degrees of freedom. The calculated and experimental heat capacities agree better than +/-3% between 8 and 250 K. Similarly, the vibrational heat capacity has been estimated for glassy water by being linked to an approximate group vibrational spectrum and the Tarasov equation (Theta (1) = 1105.5 K and Theta (3) = 72.4 K, with 6 degrees of freedom). Below the glass transition, the heat capacity of the solid starch-water system has been estimated from the appropriate sum of its components and also from a direct fitting to skeletal vibrations. Above the glass transition, the differences are interpreted as contributions of different conformational heat capacities from chains of the carbohydrates interacting with water. The conformational parts are estimated from the experimental heat capacities of dry starch and starch-water, decreased by the vibrational and external contributions to the heat capacity. (C) 2001 John Wiley & Sons, Inc.*. C1 Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Pyda, M (reprint author), Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. NR 48 TC 27 Z9 27 U1 1 U2 10 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0887-6266 J9 J POLYM SCI POL PHYS JI J. Polym. Sci. Pt. B-Polym. Phys. PD DEC 1 PY 2001 VL 39 IS 23 BP 3038 EP 3054 DI 10.1002/polb.10060 PG 17 WC Polymer Science SC Polymer Science GA 492EG UT WOS:000172155000011 ER PT J AU Fomel, S Bleistein, N AF Fomel, S Bleistein, N TI Amplitude preservation for offset continuation: Confirmation for Kirchhoff data SO JOURNAL OF SEISMIC EXPLORATION LA English DT Article DE amplitudes; continuation; DMO; approximation ID DIP MOVEOUT; SECTIONS; MEDIA AB Offset continuation (OC) is the operator that transforms common-offset seismic reflection data from one offset to another. Earlier papers by the first author presented a partial differential equation in midpoint and offset to achieve this transformation. The equation was derived from the kinematics of the continuation process with no reference to amplitudes. We present here a proof that the solution of the OC partial differential equation does propagate amplitude properly at all offsets, at least to the same order of accuracy as the Kirchhoff approximation. That is, the OC equation provides a solution with the correct traveltime and correct leading-order amplitude. "Correct amplitude" in this case means that the transformed amplitude exhibits the right geometrical spreading and reflection-surface-curvature effects for the new offset. The reflection coefficient of the original offset is preserved in this transformation, This result is more general than the earlier results in that it does not rely on the two-and-one-half dimensional assumption. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Colorado Sch Mines, Ctr Wave Phenomena, Golden, CO 80401 USA. RP Fomel, S (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, 1 Cyclotron Rd,Mail Stop 50A-1148, Berkeley, CA 94720 USA. RI Fomel, Sergey/A-3100-2009 OI Fomel, Sergey/0000-0002-9024-5137 NR 19 TC 4 Z9 4 U1 0 U2 1 PU GEOPHYSICAL PRESS PI CASTELNAU-LE-LEZ PA 14 RUE DU PRADO, 34170 CASTELNAU-LE-LEZ, FRANCE SN 0963-0651 J9 J SEISM EXPLOR JI J. Seism Explor. PD DEC PY 2001 VL 10 IS 1-3 BP 121 EP 130 PG 10 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 535NZ UT WOS:000174651700009 ER PT J AU Chi, LH Corbett, JD AF Chi, LH Corbett, JD TI Two ternary phases containing Sb-2(4-) ions: Na2M3Sb4, M=Sr, Ba. Synthesis, structure, and properties SO JOURNAL OF SOLID STATE CHEMISTRY LA English DT Article ID MAGNETIC REFRIGERATION; CRYSTAL-STRUCTURE; CLUSTERS; COMPOUND; GD-5(SI2GE2); SR; EU AB The isotypic compounds Na2Ba3Sb4 and Na2Sr3Sb4 were prepared by the direct fusion of elements at 750degreesC followed by slow cooling to, and annealing at, 300degreesC. These crystallize in the orthorhombic system, space group Pnma (No. 62), with respective lattice dimensions of a = 8.220(1), 7.919(2) Angstrom; b = 17.136(3), 16.526(5) Angstrom; c = 9.140(2), 8.801(2) A; V = 1287.5(2), 1151.7(4) V; and Z = 4. The structure of Na2Ba3Sb4 was refined from single-crystal X-ray data. All antimony atoms are dimerized as two independent Sb-2(4-) units which, together with a Na atom, center quadrilateral prisms of Ba or Sr and Na. The structure can be directly related to that of beta-Ba5Sb4 (Eu5As4, Cmca) by an oxidative distortion on cation substitution that allows the dimerization of the isolated Sb3- anions therein. The barium compound is a Zintl phase, being established as diamagnetic and semiconducting (rho(294) similar or equal to 570 muOmegacm). (C) 2001 Elsevier Science. C1 Iowa State Univ, Ames Lab, US DOE, Ames, IA 50011 USA. Iowa State Univ, Dept Chem, Ames, IA 50011 USA. RP Corbett, JD (reprint author), Iowa State Univ, Ames Lab, US DOE, Ames, IA 50011 USA. NR 28 TC 6 Z9 6 U1 0 U2 5 PU ACADEMIC PRESS INC ELSEVIER SCIENCE 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 2001 VL 162 IS 2 BP 327 EP 332 DI 10.1006/jssc.2001.9329 PG 6 WC Chemistry, Inorganic & Nuclear; Chemistry, Physical SC Chemistry GA 512ZL UT WOS:000173353400025 ER PT J AU Tressaud, A Bartlettt, N AF Tressaud, A Bartlettt, N TI Preparation, magnetic properties, and pressure-induced transitions of some (MMF6)-M-II-F-IV (M-II = Ni, Pd, Cu; M-IV = Pd, Pt, Sn) complex fluorides SO JOURNAL OF SOLID STATE CHEMISTRY LA English DT Article DE (MMF6)-M-II-F-IV; transition element fluorides; BrF3 medium; solid state reaction; ferromagnetism; pressure-induced electronic transition; piezosensors ID OXIDATION; PALLADIUM AB (MMF6)-M-II-F-IV (M-II = Ni, Pd, Cu; M-IV = Pd, Pt) and PdSnF6 complex fluorides have been synthesized via different preparative methods using either BrF3 as oxidizer and solvent, or solid state reactions. For M-II = Ni, Pd, the phases crystallize in the rhombohedral space group R (3) over bar (LiSbF6, type). Cationic ordering has been studied by X-ray diffraction and Sn-119 Mossbauer resonance for PdSnF6. A lowering of symmetry has been observed when the involved divalent cation presents a Jahn-Teller configuration (Cu-II). Except for PdSnF6, which is paramagnetic down to 4 K, all compounds are Pd2F6-type ferromagnets at low temperature. This behavior has been related to the ordering between half-filled e. orbitals of the divalent cation and empty e(g), orbitals of the tetravalent cation. A drastic increase in conductivity has been observed under high pressures. In particular the insulator-semiconductor transition induced under pressure (up to 80 kbar) in Pd2F6 corresponds to a decrease of the electrical resistivity by six orders of magnitude. The assumption of an electronic transition induced under pressure from mixed oxidation states (M-II + M-IV) to an unique trivalent M-III. oxidation state has been proposed. (C) 2001 Elsevier Science. C1 CNRS, Inst Chim Mat Condensee Bordeaux, F-33608 Pessac, France. Univ Calif Berkeley, Lawrence Berkeley Lab, Dept Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA. RP Tressaud, A (reprint author), CNRS, Inst Chim Mat Condensee Bordeaux, 87 Ave Dr A Schweitzer, F-33608 Pessac, France. NR 34 TC 5 Z9 5 U1 0 U2 1 PU ACADEMIC PRESS INC ELSEVIER SCIENCE 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 2001 VL 162 IS 2 BP 333 EP 340 DI 10.1006/jssc.2001.9331 PG 8 WC Chemistry, Inorganic & Nuclear; Chemistry, Physical SC Chemistry GA 512ZL UT WOS:000173353400026 ER PT J AU Chen, D Shirato, K Barsoum, MW El-Raghy, T Ritchie, RO AF Chen, D Shirato, K Barsoum, MW El-Raghy, T Ritchie, RO TI Cyclic fatigue-crack growth and fracture properties in Ti3SiC2 ceramics at elevated temperatures SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID SILICON-CARBIDE; MECHANICAL-PROPERTIES; ALUMINA; BEHAVIOR; NITRIDE; 1400-DEGREES-C; DISLOCATIONS; LOADS AB The cyclic fatigue and fracture toughness behavior of reactive hot-pressed Ti3SiC2 ceramics was examined at temperatures from ambient to 1200 degreesC with the objective of characterizing the high-temperature mechanisms controlling crack growth. Comparisons were made of two monolithic Ti3SiC2 materials with fine- (3-10 mum) and coarse-grained (70-300 mum) microstructures. Results indicate that fracture toughness values, derived from rising resistance-curve behavior, were significantly higher in the coarser-grained microstructure at both low and high temperatures; comparative behavior was seen under cyclic fatigue loading. In each microstructure, DeltaK(th) fatigue thresholds were found to be essentially unchanged between 25 degrees and 1100 degreesC; however, there was a sharp decrease in DeltaK(th) at 1200 degreesC (above the plastic-to-brittle transition temperature), where significant high-temperature deformation and damage are first apparent. The substantially higher cyclic-crack growth resistance of the coarse-grained Ti3SiC2 microstructure was associated with extensive crack bridging behind the crack tip and a consequent tortuous crack path. The crack-tip shielding was found to result from both the bridging of entire grains and from deformation kinking and bridging of microlamellae within grains, the latter forming by delamination along the basal planes. C1 Shanghai Jiao Tong Univ, Dept Mat Sci & Engn, Shanghai 200030, Peoples R China. Nagaoka Univ Technol, Dept Mech Engn, Niigata, Japan. Drexel Univ, Dept Mat Engn, Philadelphia, PA 19104 USA. Lawrence Berkeley Natl Lab, Div Sci Mat, Berkeley, CA USA. Univ Calif Berkeley, Dept Mat Sci & Engn, Berkeley, CA USA. RP Chen, D (reprint author), Shanghai Jiao Tong Univ, Dept Mat Sci & Engn, Shanghai 200030, Peoples R China. RI Ritchie, Robert/A-8066-2008 OI Ritchie, Robert/0000-0002-0501-6998 NR 28 TC 43 Z9 43 U1 1 U2 6 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43086-6136 USA SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD DEC PY 2001 VL 84 IS 12 BP 2914 EP 2920 PG 7 WC Materials Science, Ceramics SC Materials Science GA 503MY UT WOS:000172803300026 ER PT J AU Pavlik, RS Holland, HJ Payzant, EA AF Pavlik, RS Holland, HJ Payzant, EA TI Thermal decomposition of zircon refractories SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID EVAPORATION TECHNIQUE AB Zircon can be used to make refractory brick for the glass industry. At elevated temperatures it is known to dissociate into silica and zirconia. This study was undertaken because one of the factors that can adversely affect the quality of the glass melted in zircon-lined tanks is the degree of dissociation. The thermal dissociation of purified and unpurified zircon refractory was studied by ambient- and high-temperature X-ray diffraction (HTXRD) to understand the high-temperature performance of brick made from this material. Most of the data were collected on powders at or below 1650 degreesC; however, data were collected between 1400 degrees and 2000 degreesC. In addition, small pieces of the refractory were heated to 1650 degreesC, cooled to room temperature, and then examined under ambient conditions. The degree of dissociation was shown to be dependent on purity, particle size, peak temperature, and time at temperature. The HTXRD dissociation was monitored using the intensity of the tetragonal zirconia peaks. The monoclinic polymorph was measured in the ambient runs. High-temperature mass spectrometry (HTMS) showed that the silica is vaporized at elevated temperatures. C1 Corning Inc, Corning, NY 14831 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Corning Inc, Corning, NY 14831 USA. RI Payzant, Edward/B-5449-2009 OI Payzant, Edward/0000-0002-3447-2060 NR 16 TC 17 Z9 18 U1 1 U2 4 PU WILEY-BLACKWELL PI HOBOKEN PA 111 RIVER ST, HOBOKEN 07030-5774, NJ USA SN 0002-7820 EI 1551-2916 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD DEC PY 2001 VL 84 IS 12 BP 2930 EP 2936 PG 7 WC Materials Science, Ceramics SC Materials Science GA 503MY UT WOS:000172803300028 ER PT J AU Vedula, VR Glass, SJ Saylor, DM Rohrer, GS Carter, WC Langer, SA Fuller, ER AF Vedula, VR Glass, SJ Saylor, DM Rohrer, GS Carter, WC Langer, SA Fuller, ER TI Residual-stress predictions in polycrystalline alumina SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID GRAIN-SIZE DEPENDENCE; THERMAL-EXPANSION ANISOTROPY; FRACTURE ENERGY; CERAMICS; MICROSTRUCTURE; AL2O3; COMPOSITES; BOUNDARIES AB Microstructure-level residual stresses occur in polycrystalline ceramics during processing, as a result of thermal expansion anisotropy and crystallographic misorientation across the grain boundaries. Depending on the grain size, the magnitude of these stresses can be sufficiently high to cause spontaneous microcracking when cooled from the processing temperature. They are also likely to affect where cracks initiate and propagate under macroscopic loading. The magnitudes of residual stresses in untextured and textured alumina samples have been predicted using experimentally determined grain orientations and object-oriented finite-element analysis. The crystallographic orientations have been obtained using electron-backscattered diffraction. The residual stresses are lower and the stress distributions are narrower in the textured samples, in comparison with those in the untextured samples. Crack initiation and propagation also have been simulated, using a Griffith-like fracture criterion. The grain-boundary-energy:surface-energy ratios required for computations are estimated using atomic-force-microscopy thermal-groove measurements. C1 Sandia Natl Labs, Ceram Mat Dept, Albuquerque, NM 87185 USA. Carnegie Mellon Univ, Dept Mat Sci & Engn, Pittsburgh, PA 15213 USA. MIT, Dept Mat Sci & Engn, Cambridge, MA 02139 USA. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Vedula, VR (reprint author), United Technol Res Ctr, E Hartford, CT 06108 USA. RI Carter, W/K-2406-2012; Rohrer, Gregory/A-9420-2008 OI Rohrer, Gregory/0000-0002-9671-3034 NR 27 TC 74 Z9 74 U1 1 U2 16 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43086-6136 USA SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD DEC PY 2001 VL 84 IS 12 BP 2947 EP 2954 PG 8 WC Materials Science, Ceramics SC Materials Science GA 503MY UT WOS:000172803300030 ER PT J AU Hsueh, CH AF Hsueh, CH TI Analyses of multiple film cracking in film/substrate systems SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID SILICON-OXIDE LAYERS; THIN-FILMS; MECHANICAL-PROPERTIES; STRESS TRANSFER; SHEAR-STRENGTH; BRITTLE FILMS; SUBSTRATE; POLY(ETHYLENE-TEREPHTHALATE); INTERFACES; BEHAVIOR AB Multiple film cracking in a film/substrate system is analyzed in the present study. The system is subjected to residual stresses before loading. A constant displacement rate is applied unidirectionally to stretch the system. An analytical model is developed to derive the stress distribution in the system, and the film-cracking problem is analyzed using both the strength and the energy criteria. The predicted crack spacing as a function of the applied strain is compared with experimental measurements of multiple cracking of SiOx films with various thicknesses on poly(ethylene terephthalate) substrates. Comparison is also made between the present and other predictions. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Hsueh, CH (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RI Hsueh, Chun-Hway/G-1345-2011 NR 23 TC 12 Z9 12 U1 0 U2 3 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43086-6136 USA SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD DEC PY 2001 VL 84 IS 12 BP 2955 EP 2961 PG 7 WC Materials Science, Ceramics SC Materials Science GA 503MY UT WOS:000172803300031 ER PT J AU Schelling, PK Phillpot, SR AF Schelling, PK Phillpot, SR TI Mechanism of thermal transport in zirconia and yttria-stabilized zirconia by molecular-dynamics simulation SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID SINGLE-CRYSTALS; CUBIC ZRO2; GRAIN-SIZE; CONDUCTIVITY; TEMPERATURE; HEAT; LOCALIZATION; DIFFUSIVITY; VIBRATIONS; GLASSES AB We present results of molecular-dynamics simulations of the thermal conductivity, kappa, of ZrO2 and Y2O3-stabilized ZrO2 (YSZ). For both pure ZrO2 and YSZ with low concentrations of Y2O3, we rind that the high-temperature kappa is typical of a crystalline solid, with the dominant mechanism being phonon-phonon scattering. With increasing Y2O3 concentration, however, the mechanism changes to one more typical of an amorphous system. In particular, phononlike vibrational modes with well-defined wave vectors appear only at very low frequencies. As in amorphous materials, the vast majority of vibrational modes, while delocalized, do not propagate like ordinary phonon modes but transport energy in a diffusive manner. We also rind that the few highest frequency modes are localized and do not contribute to kappa. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Schelling, PK (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Phillpot, Simon/J-9117-2012; OI Phillpot, Simon/0000-0002-7774-6535 NR 33 TC 68 Z9 69 U1 1 U2 24 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43086-6136 USA SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD DEC PY 2001 VL 84 IS 12 BP 2997 EP 3007 PG 11 WC Materials Science, Ceramics SC Materials Science GA 503MY UT WOS:000172803300038 ER PT J AU Fernandez, FM Vadillo, JM Engelke, F Kimmel, JR Zare, RN Rodriguez, N Wetterhall, M Markides, K AF Fernandez, FM Vadillo, JM Engelke, F Kimmel, JR Zare, RN Rodriguez, N Wetterhall, M Markides, K TI Effect of sequence length, sequence frequency, and data acquisition rate on the performance of a Hadamard transform time-of-flight mass spectrometer SO JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY LA English DT Article AB Various factors influencing the performance of a Hadamard transform time-of-flight mass spectrometer (HT-TOFMS) have been investigated. Using a nitrogen corona discharge to produce an ion stream of N-2(+), N-3(+), and N-4(+), it is found for spectra containing only N-4(+) that the signal-to-noise ratio (SNR) closely approaches the value calculated from the ion background by assuming that the ion background follows a Poisson distribution. In contrast, for a more intense beam containing N-2(+), N-3(+), and N-4(+), the SNR is less than its theoretical value because of the appearance of discrete spikes in the mass spectrum caused by deviations in the actual modulation sequence from the ideal one. These spikes can be reduced, however, by decreasing the modulation voltage. Under these optimized conditions, the pseudo-random sequence length is varied to understand how it alters SNR, mass resolution, and scan speed. When the length of the pseudo-random sequence is doubled, the SNR increases by root2 while the time necessary to record a mass spectrum also doubles. Mass resolution can be varied between 500 and 1200 at m/z = 609 as the sequence length, modulation speed (10 MHz, 25 MHz), and acquisition rate (up to 50 MHz) are changed. Scan speeds of 6000 passes per s can be obtained using a sequence containing 4095 elements modulated at 25 MHz. The capability to tailor the HT-TOFMS to increase the scan speed and resolution with a constant 50% duty cycle makes the technique extremely appealing as a mass analyzer for measuring rapid changes in the composition of an ion stream. (C) 2001 American Society for Mass Spectrometry. C1 Stanford Univ, Dept Chem, Stanford, CA 94305 USA. Pacific NW Natl Lab, ESML, Richland, WA 99352 USA. Uppsala Univ, Dept Chem, Uppsala, Sweden. RP Zare, RN (reprint author), Stanford Univ, Dept Chem, Stanford, CA 94305 USA. RI Fernandez, Facundo/B-7015-2008; Zare, Richard/A-8410-2009; Vadillo, Jose/I-5334-2013 NR 20 TC 24 Z9 24 U1 0 U2 13 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 1044-0305 J9 J AM SOC MASS SPECTR JI J. Am. Soc. Mass Spectrom. PD DEC PY 2001 VL 12 IS 12 BP 1302 EP 1311 DI 10.1016/S1044-0305(01)00322-1 PG 10 WC Chemistry, Analytical; Chemistry, Physical; Spectroscopy SC Chemistry; Spectroscopy GA 500UD UT WOS:000172644400009 PM 11766757 ER PT J AU Belov, ME Gorshkov, MV Udseth, HR Smith, RD AF Belov, ME Gorshkov, MV Udseth, HR Smith, RD TI Controlled ion fragmentation in a 2-D quadrupole ion trap for external ion accumulation in ESI FTICR mass spectrometry SO JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY LA English DT Article ID STORAGE ASSISTED DISSOCIATION; COLLISION-INDUCED DISSOCIATION; ELECTROSPRAY-IONIZATION; ONLY QUADRUPOLE AB Undesired fragmentation of electrospray generated ions in an rf multipole traps can be problematic in many applications. Of special interest here is ion dissociation in a 2-D quadrupole ion trap external to a Fourier transform ion cyclotron resonance mass spectrometer (FTICR MS) used in proteomic studies. In this work, we identified the experimental parameters that determine the efficiency of ion fragmentation. We have found that under the pressure conditions used in this study there is a specific combination of the radial and axial potential well depths that determines the fragmentation threshold. This combination of rf and dc fields appears to be universal for ions of different mass-to-charge ratios, molecular weights, and charge states. Such universality allows the fragmentation efficiency of the trapped ions in the course of capillary liquid chromatography (LC) separation studied to be controlled and can increase the useful duty cycle and dynamic range of a FTICR mass spectrometer equipped with an external rf only 2-D quadrupole ion trap. (C) 2001 American Society for Mass Spectrometry. C1 Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Smith, RD (reprint author), Pacific NW Natl Lab, Environm Mol Sci Lab, MS K8-98,POB 999, Richland, WA 99352 USA. RI Gorshkov, Mikhail/E-8522-2010; Smith, Richard/J-3664-2012; Gorshkov, Mikhail/N-4984-2013 OI Smith, Richard/0000-0002-2381-2349; Gorshkov, Mikhail/0000-0001-9572-3452 FU NCRR NIH HHS [RR12365] NR 34 TC 20 Z9 21 U1 0 U2 4 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 1044-0305 J9 J AM SOC MASS SPECTR JI J. Am. Soc. Mass Spectrom. PD DEC PY 2001 VL 12 IS 12 BP 1312 EP 1319 DI 10.1016/S1044-0305(01)00318-X PG 8 WC Chemistry, Analytical; Chemistry, Physical; Spectroscopy SC Chemistry; Spectroscopy GA 500UD UT WOS:000172644400010 PM 11766758 ER PT J AU Zheng, F Zhan, CG Ornstein, RL AF Zheng, F Zhan, CG Ornstein, RL TI Theoretical studies of reaction pathways and energy barriers for alkaline hydrolysis of phosphotriesterase substrates paraoxon and related toxic phosphofluoridate nerve agents SO JOURNAL OF THE CHEMICAL SOCIETY-PERKIN TRANSACTIONS 2 LA English DT Article ID PHOSPHATE ESTER HYDROLYSIS; CARBOXYLIC-ACID ESTERS; REACTION FIELD-THEORY; TRANSITION-STATE; COMPARATIVE REACTIVITIES; 3-DIMENSIONAL STRUCTURE; MOLECULAR-INTERACTIONS; CATALYTIC HYDROLYSIS; VOLUME POLARIZATION; CHARGE PENETRATION AB Ab initio molecular orbital calculations were carried out to study reaction pathways and evaluate energy barriers for alkaline hydrolysis of O,O-diethyl p-nitrophenyl phosphate (paraoxon), diisopropyl phosphorofluoridate (DFP), O-isopropyl methylphosphonofluoridate (sarin), O-pinacolyl methylphosphonofluoridate (soman) and O, O-dimethyl phosphorofluoridate. This is the rst computational study on the reaction pathways for hydrolysis of phosphotriesters and their structural variants that have small pK(a) values for the leaving groups. The reaction coordinate calculations reveal that the hydrolysis of DFP, sarin, soman and O, O-dimethyl phosphorofluoridate proceeds through the attack of hydroxide ion at the phosphorus center to form a pentacoordinate intermediate and the decomposition of the intermediate through F leaving. The hydrolysis of paraoxon was found to occur by a one-step process, which strongly supports the conclusion, based on the previously observed primary and secondary O-18 isotope effects, of an S(N)2-like transition state with the absence of a stable pentacoordinate intermediate during the paraoxon hydrolysis. The energy barriers calculated in the gas phase for the pentacoordinate intermediate decomposition step are slightly lower than for the formation step for DFP and sarin, and are higher for soman and O, O-dimethyl phosphorofluoridate. Solvent effects significantly increase the energy barriers for the pentacoordinate intermediate formation step and significantly decrease the energy barriers for the decomposition step. Thus, the pentacoordinate intermediate formation step of hydrolysis in aqueous solution is always rate-determining. For the hydrolysis of all the compounds examined in this study, the energy barrier, 0.8 kcal mol(-1), calculated for the paraoxon hydrolysis is the lowest in the gas phase, whereas the corresponding barrier, 10.1 kcal mol(-1), is the highest in aqueous solution. For the hydrolysis of sarin in aqueous solution, for which the experimental activation energy is available, the calculated energy barrier of 8.6 kcal mol(-1) for the pentacoordinate intermediate formation (i.e. the rate-determining step) is in good agreement with the experimental activation energy of 9.1 kcal mol(-1). Finally, the relative magnitudes of the energy barriers calculated for the alkaline hydrolysis were qualitatively compared with the relative magnitudes of the available experimental rate constants reported for the corresponding phosphotriesterase-catalyzed hydrolysis, and were employed to discuss substituent effects. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. Columbia Univ Coll Phys & Surg, Dept Med, New York, NY 10032 USA. RP Zhan, CG (reprint author), Pacific NW Natl Lab, Mailstop K2-21,Battelle Blvd,POB 999, Richland, WA 99352 USA. NR 70 TC 62 Z9 63 U1 0 U2 6 PU ROYAL SOC CHEMISTRY PI CAMBRIDGE PA THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD,, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND SN 1472-779X J9 J CHEM SOC PERK T 2 JI J. Chem. Soc.-Perkin Trans. 2 PD DEC PY 2001 IS 12 BP 2355 EP 2363 DI 10.1039/b101747k PG 9 WC Chemistry, Organic; Chemistry, Physical SC Chemistry GA 503ML UT WOS:000172802200021 ER PT J AU Perkins, JD Bahn, CS McGraw, JM Parilla, PA Ginley, DS AF Perkins, JD Bahn, CS McGraw, JM Parilla, PA Ginley, DS TI Pulsed laser deposition and characterization of crystalline lithium cobalt dioxide, (LiCoO2) thin films SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID ION DIFFUSION MEASUREMENTS; BATTERY CATHODES; THERMAL-STABILITY; LIXCOO2; INTERCALATION; SPINEL; CELLS; OXIDE AB The pulsed laser deposition of LiCoO2 and LiCo0.5Al0.5O2 thin films was investigated as a function of deposition conditions. The initial growth process optimization focused on films grown on (200)-textured SnO2-coated glass substrates. Film growth was also investigated on ZnO and indium-tin oxide (ITO) coated substrates. For both LiCoO2 and LiCo0.5Al0.5O2, dense uniaxially textured (003)-oriented films of the layered LiCoO2 phase were grown on the SnO2 coated substrates. The grain size increased substantially with increased substrate temperature in the range from 400 to 700 degreesC. For constant current cycling between 3.5 and 4.4 V vs. Li, the best crystalline LiCoO2 films, grown at T-s = 700 degreesC, p(O2) = 2000 mTorr, had an initial discharge capacity of similar to 118 mAh/g (0.43 Li/Co) which decreased similar to0.5% per cycle. For LiCo0.5Al0.5O2, although, as predicted, the films did have a higher cathode potential, the charge capacity was significantly lower than that for LiCoO2 films. Finally, functional LiCoO2 thin film cathodes were grown on flexible ITO-coated Upilex polymer substrates at T-s = 300 degreesC. (C) 2001 The Electrochemical Society. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Perkins, JD (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. NR 28 TC 45 Z9 46 U1 3 U2 27 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 65 SOUTH MAIN STREET, PENNINGTON, NJ 08534 USA SN 0013-4651 J9 J ELECTROCHEM SOC JI J. Electrochem. Soc. PD DEC PY 2001 VL 148 IS 12 BP A1302 EP A1312 DI 10.1149/1.1415029 PG 11 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA 492KD UT WOS:000172166800003 ER PT J AU Zhang, XR Kostecki, R Richardson, TJ Pugh, JK Ross, PN AF Zhang, XR Kostecki, R Richardson, TJ Pugh, JK Ross, PN TI Electrochemical and infrared studies of the reduction of organic carbonates SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID PROPYLENE CARBONATE; ELECTRODE; BEHAVIOR; GRAPHITE; SYSTEM AB The reduction potentials of five organic carbonates commonly employed in lithium battery electrolytes, ethylene carbonate (EC), propylene carbonate (PC), diethyl carbonate (DEC), dimethyl carbonate (DMC), and vinylene carbonate (VC) were determined by cyclic voltammetry using inert (Au or glassy carbon) electrodes in tetrahydrofuran/LiClO4 supporting electrolyte. The reduction potentials for all five organic carbonates were above 1 V (vs. Li/Li+). PC reduction was observed to have a significant kinetic hindrance. The measured reduction potentials for EC, DEC, and PC were consistent with thermodynamic values calculated using density functional theory (DFT) assuming one-electron reduction to the radical anion. The experimental values for VC and DMC were, however, much more positive than the calculated values, which we attribute to different reaction pathways. The role of VC as an additive in a PC-based electrolyte was investigated using conventional constant-current cycling combined with ex situ infrared spectroscopy and in situ atomic force microscopy (AFM). We confirmed stable cycling of a commercial li-ion battery carbon anode in a PC-based electrolyte with 5 mol % VC added. The preferential reduction of VC and the solid electrolyte interphase layer formation therefrom appears to inhibit PC cointercalation and subsequent graphite exfoliation. (C) 2001 The Electrochemical Society. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Zhang, XR (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. NR 11 TC 149 Z9 151 U1 12 U2 107 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 65 SOUTH MAIN STREET, PENNINGTON, NJ 08534 USA SN 0013-4651 J9 J ELECTROCHEM SOC JI J. Electrochem. Soc. PD DEC PY 2001 VL 148 IS 12 BP A1341 EP A1345 DI 10.1149/1.1415547 PG 5 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA 492KD UT WOS:000172166800007 ER PT J AU Treimer, SE Feng, JR Scholten, MD Johnson, DC Davenport, AJ AF Treimer, SE Feng, JR Scholten, MD Johnson, DC Davenport, AJ TI Comparison of voltammetric responses of toluene and xylenes at iron(III)-doped, bismuth(V)-doped, and undoped beta-lead dioxide film electrodes in 0.50 M H2SO4 SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID ANODIC OXYGEN-TRANSFER; PBO2-FILM ELECTRODES; ELECTROCATALYSIS; EVOLUTION; FLUORIDE; OZONE; IRON AB Voltammetric activities are compared for the designated compounds in 0.50 M H2SO4 at the specified film electrodes configured as rotated disks. The effective number of electrons (n(eff), equiv mol(-1)) calculated from the Koutecky-Levich plot is 3.1 +/- 0.2 for toluene oxidation at the Fe-PbO2 electrode, compared to 2.0 +/- 0.05 and 4.1 +/- 0.3 at the Bi-PbO2 and PbO2 electrodes, respectively. Gas chromatography-mass spectrometry data confirm that the primary product of toluene oxidation is benzyl alcohol (2 equiv mol(-1)) at the Fe-PbO2 electrode with production of small amounts of benzaldehyde (4 equiv mol(-1))and benzoic acid ( equiv mol(-1)) X-ray photoelectron spectroscopy data indicate the ratio of Fe: Pb is ca. 1:100 (atom: atom) in the Fe-PbO2 films. By comparison, a Bi: Pb ratio of 33:100 (atom: atom) is easily attained in Bi-PbO2 films. Nevertheless, the apparent heterogeneous rate constant (k(app), cm s(-1)) for toluene oxidation is larger at the Fe-PbO2 electrode (6.5 +/- 0.06 x 10(-3)) compared to the Bi-PbO2 electrode (2.0 +/- 0.05 x 10(-3)). X-ray absorption near-edge structure data confirm speculation that iron exists in the 3+ oxidation state with octahedral coordination by O atoms in Fe-PbO2 films. The large activity of the Fe-PbO2 electrode is attributed to the benefit of adsorption of aromatic molecules at Fe(III) sites. (C) 2001 The Electrochemical Society. C1 Iowa State Univ, Dept Chem, Ames, IA 50011 USA. Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Univ Birmingham, Sch Met & Mat, Birmingham B15 2TT, W Midlands, England. RP Treimer, SE (reprint author), Iowa State Univ, Dept Chem, Ames, IA 50011 USA. RI Davenport, Alison/J-6089-2013 OI Davenport, Alison/0000-0003-0853-515X NR 24 TC 34 Z9 35 U1 1 U2 12 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 65 SOUTH MAIN STREET, PENNINGTON, NJ 08534 USA SN 0013-4651 J9 J ELECTROCHEM SOC JI J. Electrochem. Soc. PD DEC PY 2001 VL 148 IS 12 BP E459 EP E463 DI 10.1149/1.1413991 PG 5 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA 492KD UT WOS:000172166800024 ER PT J AU Cho, HS Kang, SM Jung, MH Hong, DK Kadyk, J Kim, JG AF Cho, HS Kang, SM Jung, MH Hong, DK Kadyk, J Kim, JG TI Recent development of fast position-sensitive gaseous detectors with high position accuracy SO JOURNAL OF THE KOREAN PHYSICAL SOCIETY LA English DT Article ID ELECTRONIC CONDUCTIVITY; MICROSTRIP; PERFORMANCE; CHAMBERS; GLASS AB A new class of fast position-sensitive radiation detectors with high position accuracy, the so-called the microstrip gas chamber (MSGC), is described for future applications in the fields of nuclear and high-energy physics, and medical imaging. The new technique involves the use of doped amorphous silicon carbide (a-Si:H:C) as a semiconductive. coating in the detector fabrication to eliminate the effect of charge accumulation on the substrate surface. The performance of these detectors has been tested by measuring gas gains with respect to operating parameters such as the anode voltage and time. This development may lead to a significant improvement in the operation of gas avalanche detectors in terms of high position accuracy and large signal enhancement. C1 Yonsei Univ, Dept Med Engn, Res Inst Biomed Engn, Coll Hlth Sci, Wonju 220710, South Korea. Lawrence Berkeley Natl Lab, Div Phys, Berkeley, CA 94720 USA. RP Cho, HS (reprint author), Yonsei Univ, Dept Med Engn, Res Inst Biomed Engn, Coll Hlth Sci, Wonju 220710, South Korea. NR 8 TC 3 Z9 3 U1 0 U2 1 PU KOREAN PHYSICAL SOC PI SEOUL PA 635-4, YUKSAM-DONG, KANGNAM-KU, SEOUL 135-703, SOUTH KOREA SN 0374-4884 J9 J KOREAN PHYS SOC JI J. Korean Phys. Soc. PD DEC PY 2001 VL 39 IS 6 BP 980 EP 983 PG 4 WC Physics, Multidisciplinary SC Physics GA 502ZL UT WOS:000172772600007 ER PT J AU Martin, LA Mulholland, PJ Webster, JR Valett, HM AF Martin, LA Mulholland, PJ Webster, JR Valett, HM TI Denitrification potential in sediments of headwater streams in the southern Appalachian Mountains, USA SO JOURNAL OF THE NORTH AMERICAN BENTHOLOGICAL SOCIETY LA English DT Article DE denitrification; sediments; nutrient limitations; temporal variability; nitrate; dissolved organic carbon; nitrogen deposition; stream ecology ID GREAT-SMOKY-MOUNTAINS; HYPORHEIC ZONE; FOREST STREAM; NITROGEN; NUTRIENT; SOILS; ACETYLENE; ECOSYSTEM; NITRATE; WATER AB We investigated variations in resource availability (NO3-N and labile organic C [LOC]) as determinants of potential denitrification in stream sediments in the southern Appalachian Mountains, USA. Stream water and sediments were sampled seasonally in 2 streams of contrasting NO3-N availability, Noland Creek (high NO3-N) and Walker Branch (low NO3-N). Eight additional streams with varying NO3-N levels were sampled once during summer. Stream sediments were incubated at ambient stream temperatures, and nitrous oxide accumulation was quantified following acetylene inhibition of nitrous oxide reduction. Denitrification potential was greater in Noland Creek than Walker Branch. In autumn and spring, NO3-N and LOC amendments indicated that denitrification potential in Walker Branch sediments was NO3-N limited, whereas temperature had no effect on rates. Denitrification potential in Noland Creek sediments was not limited by NO3-N or LOC, but was significantly affected by season and temperature. However, no differences in denitrification potential were detected when Noland Creek seasonal data were adjusted to a common temperature. NO3-N in the 10 surveyed streams ranged from 10 to 549 mug/L, with the highest NO3-N levels and denitrification rates generally occurring in the higher-elevation streams of Great Smoky Mountains National Park. Our results suggest that NO3-N availability is the primary factor limiting potential denitrification in Southern Appalachian streams. Despite the ideal conditions of slurry studies, extrapolation of potential rates to estimate denitrification loss in the catchment channels indicates that the process is an insignificant N sink (1.7% of stream N export in Walker Branch and 1.5% of N export in the Noland Divide Watershed). C1 Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. Virginia Polytech Inst & State Univ, Dept Biol, Blacksburg, VA 24061 USA. RP Martin, LA (reprint author), Stroud Water Res Ctr, 970 Spencer Rd, Avondale, PA 19311 USA. RI Mulholland, Patrick/C-3142-2012 NR 45 TC 50 Z9 53 U1 1 U2 20 PU NORTH AMER BENTHOLOGICAL SOC PI LAWRENCE PA 1041 NEW HAMSPHIRE STREET, LAWRENCE, KS 66044 USA SN 0887-3593 J9 J N AM BENTHOL SOC JI J. N. Am. Benthol. Soc. PD DEC PY 2001 VL 20 IS 4 BP 505 EP 519 DI 10.2307/1468084 PG 15 WC Ecology; Marine & Freshwater Biology SC Environmental Sciences & Ecology; Marine & Freshwater Biology GA 498NK UT WOS:000172517400001 ER PT J AU Beer, BE Foley, BT Kuiken, CL Tooze, Z Goeken, RM Brown, CR Hu, JJ St Claire, M Korber, BT Hirsch, VM AF Beer, BE Foley, BT Kuiken, CL Tooze, Z Goeken, RM Brown, CR Hu, JJ St Claire, M Korber, BT Hirsch, VM TI Characterization of novel simian immunodeficiency viruses from red-capped mangabeys from Nigeria (SIVrcmNG409 and-NG411) SO JOURNAL OF VIROLOGY LA English DT Article ID AFRICAN-GREEN MONKEYS; WILD-CAPTURED CHIMPANZEE; NATURAL INFECTION; HIGHLY DIVERGENT; MOLECULAR CHARACTERIZATION; SEROEPIDEMIOLOGIC SURVEY; CERCOPITHECUS-AETHIOPS; PRIMATE LENTIVIRUS; TANTALUS MONKEYS; GRIVET MONKEYS AB Two novel simian immunodeficiency virus (SIV) strains from wild-caught red-capped mangabeys (Cercocebus torquatus torquatus) from Nigeria were characterized. Sequence analysis of the fully sequenced SIV strain rcmNG411 (SIVrcmNG411) and gag and pol sequence of SIVrcmNG409 revealed that they were genetically most closely related to the recently characterized SIVrcm from Gabon (SIVrcmGB1). Thus, red-capped mangabeys from distant geographic locations harbor a common lineage of SIV. SIVrcmNG411 carried a vpx gene in addition to vpr, suggesting a common evolutionary ancestor with SIVsm (from sooty mangabeys). However, SIVrcm was only marginally closer to SIVsm in that region than to any of the other lentiviruses. SIVrcm showed the highest similarity in pol with SIVdrl, isolated from a drill, a primate that is phylogenetically distinct from mangabey monkeys, and clustered with other primate lentiviruses (primarily SIVcpz [from chimpanzees] and SIVagmSab [from African green monkeys]) discordantly in different regions of the genome, suggesting a history of recombination. Despite the genetic relationship to SIVcpz in the pol gene, SIVrcmNG411 did not replicate in chimpanzee peripheral blood mononuclear cells (PBMC), although two other viruses unrelated to SIVcpz, SIVmndGB1 (from mandrills) and SIVlhoest (from L'Hoest monkeys), were able to grow in chimpanzee PBMC. The CCR5 24-bp deletion previously described in red-capped mangabeys from Gabon was also observed in Nigerian red-capped mangabeys, and SIVrcmNG411, like SIVrcmGB1, used CCR2B and STRL33 as coreceptors for virus entry. SIVrcm, SIVsm, SIVmndGB1, and all four SIvlhoest isolates but not SfVsun (from sun-tailed monkeys) replicated efficiently in human PBMC, suggesting that the ability to infect the human host can vary within one lineage. C1 NIAID, Mol Microbiol Lab, NIH, Rockville, MD 20852 USA. Los Alamos Natl Lab, Grp T10, Los Alamos, NM 87545 USA. Bioqual Inc, Rockville, MD 20850 USA. Cercopan, Calabar, CRS, Nigeria. RP Hirsch, VM (reprint author), NIAID, Mol Microbiol Lab, NIH, Rockville, MD 20852 USA. OI Foley, Brian/0000-0002-1086-0296; Korber, Bette/0000-0002-2026-5757 NR 47 TC 80 Z9 80 U1 0 U2 2 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1752 N ST NW, WASHINGTON, DC 20036-2904 USA SN 0022-538X J9 J VIROL JI J. Virol. PD DEC PY 2001 VL 75 IS 24 BP 12014 EP 12027 DI 10.1128/JVI.75.24.12014-12027.2001 PG 14 WC Virology SC Virology GA 495RZ UT WOS:000172355300009 PM 11711592 ER PT J AU Spielman, RB De Groot, JS AF Spielman, RB De Groot, JS TI Z pinches - A historical view SO LASER AND PARTICLE BEAMS LA English DT Review ID RAYLEIGH-TAYLOR INSTABILITY; PUFF Z-PINCH; ARRAY Z-PINCHES; REVERSED FIELD PINCH; X-RAY POWER; WIRE-ARRAY; MAGNETIC-FIELDS; TARGET DESIGN; HIGH-VELOCITY; IMPLOSION AB Z pinches have a long and varied history. Beginning in the 18th century, z pinches have been used to heat plasmas very efficiently. Early in the nuclear fusion program, it was realized that modest currents are required to confine plasma that could produce energy gain. The instability of the confined plasma was convincingly demonstrated in experiments in the 1950s that were performed around the world. These uniformly negative results led to z pinches being dropped as a fusion concept. Recent progress in fast z pinches has reinvigorated the field. We review the field and highlight the recent advances that point the way to a bright future for z pinches. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Univ Calif Davis, Dept Appl Sci, Davis, CA 95616 USA. Univ Calif Davis, Plasma Res Grp, Davis, CA 95616 USA. RP Spielman, RB (reprint author), MS 1194,POB 5800, Albuquerque, NM 87185 USA. NR 133 TC 16 Z9 20 U1 1 U2 3 PU CAMBRIDGE UNIV PRESS PI NEW YORK PA 40 WEST 20TH ST, NEW YORK, NY 10011-4221 USA SN 0263-0346 J9 LASER PART BEAMS JI Laser Part. Beams PD DEC PY 2001 VL 19 IS 4 BP 509 EP 525 DI 10.1017/S0263034601194012 PG 17 WC Physics, Applied SC Physics GA 554PN UT WOS:000175744800002 ER PT J AU Douglas, MR De Groot, JS Spielman, RB AF Douglas, MR De Groot, JS Spielman, RB TI The magneto-Rayleigh-Taylor instability in dynamic z pinches SO LASER AND PARTICLE BEAMS LA English DT Review ID ARRAY Z-PINCHES; X-RAY POWER; INERTIAL CONFINEMENT FUSION; TAILORED DENSITY PROFILES; SHELL GAS PUFF; WIRE-ARRAY; PLASMA FORMATION; HIGH-VELOCITY; SINGLE-MODE; EMISSION CHARACTERISTICS AB The magneto-Rayleigh-Taylor (MRT) instability limits the performance of dynamic z pinches. This instability develops at the plasma-vacuum/field interface, growing in amplitude throughout the implosion, thereby reducing the peak plasma velocity and spatial uniformity at stagnation. MRT instabilities are believed to play a dominant role in the case of high wire number arrays, gas puffs and foils. In this article, the MRT instability is discussed in terms of initial seeding, linear and nonlinear growth, experimental evidence, radiation magnetohydrodynamic simulations, and mitigating schemes. A number of experimental results are presented, where the mitigating schemes have been realized. In general, the problem is inherently three dimensional, but two-dimensional simulations together with theory and experiment enhance our physical understanding and provide insight into future load design. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Sandia Natl Labs, POB 5800, Albuquerque, NM 87112 USA. EM mrdougl@sandia.gov NR 112 TC 14 Z9 14 U1 1 U2 3 PU CAMBRIDGE UNIV PRESS PI NEW YORK PA 32 AVENUE OF THE AMERICAS, NEW YORK, NY 10013-2473 USA SN 0263-0346 EI 1469-803X J9 LASER PART BEAMS JI Laser Part. Beams PD DEC PY 2001 VL 19 IS 4 BP 527 EP 540 DI 10.1017/S0263034600194029 PG 14 WC Physics, Applied SC Physics GA 554PN UT WOS:000175744800003 ER PT J AU Sanford, TWL AF Sanford, TWL TI Wire number breakthrough for high-power annular z pinches and some characteristics at high wire number SO LASER AND PARTICLE BEAMS LA English DT Article ID ARRAY Z-PINCH; NATIONAL-IGNITION-FACILITY; X-RAY POWER; INERTIAL-CONFINEMENT-FUSION; 2-DIMENSIONAL SIMULATIONS; DIAGNOSTIC PACKAGE; RELEVANT HOHLRAUMS; PLASMA FORMATION; HIGH-TEMPERATURE; CAPSULE DESIGN AB Characteristics of annular wire array z pinches as a function of wire number and at high wire number are reviewed. The data, taken primarily using aluminum wires on Saturn, are comprehensive. The experiments have provided important insights into the features of wire-array dynamics critical for high X-ray power generation, and have initiated a renaissance in z pinches when high numbers of wires are used. In this regime, for example, radiation environments characteristic of those encountered during the early pulses required for indirect-drive ICF ignition on the NIF have been produced in hohlraums driven by X rays from a z pinch, and arc commented on here. C1 Sandia Natl Labs, Org 1677, Albuquerque, NM 87185 USA. RP Sanford, TWL (reprint author), Sandia Natl Labs, Org 1677, MS-1196,POB 5800, Albuquerque, NM 87185 USA. EM twsanfo@sandia.gov NR 86 TC 12 Z9 12 U1 0 U2 1 PU CAMBRIDGE UNIV PRESS PI NEW YORK PA 32 AVENUE OF THE AMERICAS, NEW YORK, NY 10013-2473 USA SN 0263-0346 J9 LASER PART BEAMS JI Laser Part. Beams PD DEC PY 2001 VL 19 IS 4 BP 541 EP 556 DI 10.1017/S0263034601194036 PG 16 WC Physics, Applied SC Physics GA 554PN UT WOS:000175744800004 ER PT J AU Beach, RJ Freitas, BL AF Beach, RJ Freitas, BL TI Practical 100-kW-class diode arrays emerge SO LASER FOCUS WORLD LA English DT Article ID MICROCHANNEL AB A laser-diode packaging technology, based on Integration that makes It suitable for the construction of large laser-diode arrays, boasts 10- to 100-kW output power capabilities. C1 Lawrence Livermore Natl Lab, US DOE, Livermore, CA 94551 USA. RP Lawrence Livermore Natl Lab, US DOE, POB 808, Livermore, CA 94551 USA. EM beach2@llnl.gov NR 4 TC 1 Z9 2 U1 0 U2 0 PU PENNWELL PUBL CO PI NASHUA PA 98 SPIT BROOK RD, NASHUA, NH 03062-2801 USA SN 1043-8092 J9 LASER FOCUS WORLD JI Laser Focus World PD DEC PY 2001 VL 37 IS 12 BP 103 EP 107 PG 5 WC Optics SC Optics GA 501MR UT WOS:000172688900023 ER PT J AU Soher, B Maudsley, A AF Soher, B Maudsley, A TI Response to "Comments on 'Confidence images for MR spectroscopic imaging' by Leentje Vanhamme, Philippe Lemmerling, and Sabine Van Huffel" SO MAGNETIC RESONANCE IN MEDICINE LA English DT Letter C1 Univ Calif San Francisco, San Francisco, CA 94143 USA. No Calif Inst Res & Educ, San Francisco, CA USA. Univ Calif Los Angeles, Los Angeles, CA 90024 USA. Stanford Linear Accelerator Ctr, Palo Alto, CA USA. RP Maudsley, A (reprint author), DVA Med Ctr, MR Unit, 114M,4150 Clement St, San Francisco, CA 94121 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0740-3194 J9 MAGNET RESON MED JI Magn. Reson. Med. PD DEC PY 2001 VL 46 IS 6 BP 1256 EP 1256 PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 497BM UT WOS:000172432900031 ER PT J AU Cooper, LW Hong, GH Beasley, TM Grebmeier, JM AF Cooper, LW Hong, GH Beasley, TM Grebmeier, JM TI Iodine-129 concentrations in marginal seas of the North Pacific and Pacific-influenced waters of the Arctic Ocean SO MARINE POLLUTION BULLETIN LA English DT Article DE artificial radioactivity; east sea (sea of Japan); bering sea; chukchi sea; Iodine-129 ID FUEL-REPROCESSING FACILITIES; JAPAN SEA; I-129; TRACER; DISTRIBUTIONS; RADIONUCLIDES; TRANSPORT; ISOTOPES; SEAWATER; AMS AB Water sampling during the 1993 IV Russian-US Joint Expedition to the Bering and Chukchi Seas (BERPAC) indicates that Pacific Ocean burdens of the long-lived radionuclide I-129 are relatively low in the Pacific-influenced Arctic, particularly compared to high latitude waters influenced by the North Atlantic. These low concentrations occur despite the presence of potential submerged anthropogenic sources in the East Sea (Sea of Japan), and in the northwest Pacific Ocean, east of the Kamchatka Peninsula. The concentration of I-129 entering the Arctic Ocean through Bering Strait, similar to0.7 x 10(8) atoms kg(-1), is only slightly higher than observed in deep Pacific waters. Similar concentrations (0.44-0.76 x 10(8) atoms kg(-1)) measured in Long Strait indicate no significant transfer of I-129 eastward into the Chukchi Sea in the Siberian Coastal Current from the Siberian marginal seas to the west. However, the concentrations reported here are more than an order of magnitude higher than the Bering Strait input concentration estimated (1.0 X 10(6) atoms kg(-1)) from bomb fallout mass balances, which supports other existing evidence for a significant atmospheric deposition term for this radionuclide in surface ocean waters. Near-bottom water samples collected in productive waters of the Bering and Chukchi Seas also suggest that sediment regeneration may locally elevate I-129 concentrations, and impact its utility as a water mass tracer. As part of this study, two deep I-129 profiles were also measured in the East Sea in 1993-1994. The near-surface concentration of I-129 ranged from 0.12 to 0.31 x 10(8) atoms kg(-1). The I-129 concentration showed a steady decrease with depth, although because of active deep water ventilation, the entire 3000 m water column exceeded natural concentrations of the radionuclide. Atom ratios Of I-129/Cs-137 in the East Sea also suggest an excess of I-129 above bomb fallout estimates, also possibly resulting from atmospheric deposition ultimately originating from nuclear facilities. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Univ Tennessee, Dept Ecol & Evolutionary Biol, Knoxville, TN 37996 USA. Korea Ocean Res & Dev Inst, Seoul 425600, South Korea. US DOE, New York, NY 10014 USA. RP Univ Tennessee, Dept Ecol & Evolutionary Biol, 569 Dabney Hall, Knoxville, TN 37996 USA. RI Cooper, Lee/E-5251-2012; Grebmeier, Jacqueline/L-9805-2013 OI Cooper, Lee/0000-0001-7734-8388; Grebmeier, Jacqueline/0000-0001-7624-3568 NR 43 TC 15 Z9 17 U1 0 U2 10 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0025-326X EI 1879-3363 J9 MAR POLLUT BULL JI Mar. Pollut. Bull. PD DEC PY 2001 VL 42 IS 12 BP 1347 EP 1356 DI 10.1016/S0025-326X(01)00151-5 PG 10 WC Environmental Sciences; Marine & Freshwater Biology SC Environmental Sciences & Ecology; Marine & Freshwater Biology GA 507VP UT WOS:000173052200023 PM 11827122 ER PT J AU Ferreyra, E Murr, LE Russell, DP Bingert, JF AF Ferreyra, E Murr, LE Russell, DP Bingert, JF TI Elastic interactions and the metallurgical and acoustic effects of carbon in the Caribbean steel drum SO MATERIALS CHARACTERIZATION LA English DT Article DE low-carbon steel; microstructures; strain aging; Portevin-Le Chatelier effect; tempering diagrams ID MODE-LOCALIZED OSCILLATORS; MATERIALS SCIENCE; TRANSFORMATION; MARTENSITE; MECHANISM; LATTICE; SYSTEM; PLATES; MUSIC AB Requisite amounts of carbon interact with dislocations in deformed drum steel composing the note platform for the Caribbean steel drum (or pan) to produce complex, nonlinear behavior, especially notable in harmonic frequency spectra. Experiments on flat, circular disks prepared front high-quality, low-carbon (0.04 wt,% C) drum steel illustrate harmonic spectrum changes and frequency peak variation (which appear to occur by splitting), which is related to characteristic deformation (or strain). This, in turn, is related to dislocation density. Similar frequency variation characteristics were also observed in actual drum notes. Detailed texture measurements revealed only about 3% variation in the elastic moduli for the undeformed and heavily deformed drum steel. Detailed tempering diagrams illustrate the variations of residual microhardness with aging temperature, time, strain, and carbon content, while stress-strain diagrams show more detailed carbon dislocation dynamic interactions. While strain aging is a prominent feature of drum tempering, high-quality instruments can be developed and tuned even without noticeable strain aging by varying the methodology to manipulate the internal stresses to produce requisite elastic-plastic interactions. This could be achieved by strain-induced ordering of interstitial carbon (Snoek effect) and by dislocation pinning and unpinning by carbon atoms in a dynamic fashion (Portevin-Le Chitelier effect). A carbon threshold occurs below about 0.02 wt.% C and an anomalous hardening occurs in drum steels heat-treated at 800 degreesC due to martensite nucleating and growing at the original ferrite grain boundaries upon quenching, This microstructure is carbon-dependent, increasing with increasing carbon content above the similar to 0.02 wt.% C threshold. Below this carbon threshold, there is no strain aging or high-temperature hardening. Frequency spectra from heat-treated disks show an enhancement of the frequency variations and the generation of more harmonics. (C) 2001 Elsevier Science Inc. All rights reserved. C1 Univ Texas, Dept Met & Mat Engn, El Paso, TX 79968 USA. Univ Texas, Mat Res Inst, El Paso, TX 79968 USA. Baylor Univ, Dept Phys, Waco, TX 76798 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Murr, LE (reprint author), Univ Texas, Dept Met & Mat Engn, El Paso, TX 79968 USA. OI Murr, Lawrence/0000-0001-5942-8376 NR 43 TC 6 Z9 6 U1 0 U2 2 PU ELSEVIER SCIENCE INC PI NEW YORK PA 360 PARK AVE SOUTH, NEW YORK, NY 10010-1710 USA SN 1044-5803 J9 MATER CHARACT JI Mater. Charact. PD DEC PY 2001 VL 47 IS 5 BP 325 EP 363 AR PII S1044-5803(01)00187-5 DI 10.1016/S1044-5803(01)00187-5 PG 39 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Materials Science, Characterization & Testing SC Materials Science; Metallurgy & Metallurgical Engineering GA 556UX UT WOS:000175868300001 ER PT J AU Mills, MJ Fraser, HL Mukherjee, AK Nix, WD Schwarz, RB AF Mills, MJ Fraser, HL Mukherjee, AK Nix, WD Schwarz, RB TI Special issue - 12th International Conference on the Strength of Materials - ICSMA-12 - Preface SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Editorial Material C1 Ohio State Univ, Columbus, OH 43210 USA. Univ Calif Davis, Davis, CA 95616 USA. Stanford Univ, Stanford, CA 94305 USA. Los Alamos Natl Lab, Los Alamos, CA USA. RP Mills, MJ (reprint author), Ohio State Univ, Columbus, OH 43210 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 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 PY 2001 VL 319 SI SI BP XVII EP XVII DI 10.1016/S0921-5093(00)02000-1 PG 1 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 510ME UT WOS:000173211200001 ER PT J AU Hughes, DA AF Hughes, DA TI Microstructure evolution, slip patterns and flow stress SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article; Proceedings Paper CT 12th International Conference on the Strength of Materials (ICSMA 12) CY AUG 27-SEP 01, 2000 CL ASILOMAR, CA DE dislocations; scaling; flow stress; slip pattern; dislocation boundaries; misorientation angle; Stage III; Stage IV ID ENERGY DISLOCATION-STRUCTURES; STRAIN PLASTIC-DEFORMATION; COLD-ROLLED ALUMINUM; SINGLE-CRYSTALS; FCC METALS; CELL STRUCTURES; BOUNDARIES; ORIENTATION; NICKEL; WORK AB The development of deformation microstructures in medium to high stacking fault energy fcc metals is reviewed illustrating that the basic microstructural element is a cell block. The elongated cell blocks are defined by extended nearly planar boundaries that lie on special planes and enclose a group of approximately equiaxed cells. This duplex structure persists throughout Stage H-M What is known about the origins of these structures and the role of the slip pattern is reviewed. Taking all the measurable structural parameters with respect to the cell blocks: spacing. misorientation angle, and dislocation density, and assuming additive strength contributions, flow stress predictions are derived from Hall-Petch and dislocation strengthening. These predictions are in good agreement with the stress values and hardening rates observed experimentally. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Sandia Natl Labs, Ctr Mat Sci & Engn, Livermore, CA 94551 USA. RP Sandia Natl Labs, Ctr Mat Sci & Engn, POB 969,MS 9405, Livermore, CA 94551 USA. EM darcyhu@sandia.gov NR 70 TC 57 Z9 59 U1 1 U2 20 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 PY 2001 VL 319 SI SI BP 46 EP 54 DI 10.1016/S0921-5093(01)01028-0 PG 9 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 510ME UT WOS:000173211200009 ER PT J AU Yoo, MH Agnew, SR Morris, JR Ho, KM AF Yoo, MH Agnew, SR Morris, JR Ho, KM TI Non-basal slip systems in HCP metals and alloys: source mechanisms SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article; Proceedings Paper CT 12th Meeting of the International Conference on the Strength of Materials (ICSMA 12) CY AUG 27-SEP 01, 2000 CL ASILOMAR, CALIFORNIA DE beryllium; cross-slip process; elastic interaction; hexagonal close-packed metals (hcp); magnesium; non-basal (c + a) slip dislocation; stacking fault energies; titanium ID SCREW DISLOCATIONS; PRISMATIC SLIP; ALPHA-TITANIUM; ATOMISTIC SIMULATION; PLASTIC-DEFORMATION; SINGLE-CRYSTALS; CORE STRUCTURE; MAGNESIUM; TEMPERATURES; BERYLLIUM AB A possible source mechanism for non-basal slip dislocations is proposed based on the formation of an attractive junction between glissile and sessile e dislocations from the prism plane into a pyramidal plane. The driving force for the junction formation, which comes from the long-range elastic interaction between c and dislocations, is relatively large in most hexagonal close-packed (hcp) metals. Beryllium, which has an unusually low Poisson's ratio, is an exception to this rule. The cross-slip process is energetically unfavorable in Mg and Ti, from a viewpoint of the change in anisotropic elastic line tension, but it becomes favorable in Ti at elevated temperatures above 300degreesC. Discussion is given on intrinsic stacking fault energies and kinetic aspects of the cross slip. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Ames Lab, Ames, IA 50011 USA. RP Yoo, MH (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RI Morris, J/I-4452-2012 OI Morris, J/0000-0002-8464-9047 NR 32 TC 113 Z9 119 U1 7 U2 77 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 PY 2001 VL 319 SI SI BP 87 EP 92 DI 10.1016/S0921-5093(01)01027-9 PG 6 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 510ME UT WOS:000173211200014 ER PT J AU Foiles, SM Medlin, DL AF Foiles, SM Medlin, DL TI Structure and climb of 1/3 < 111 > twin dislocations in aluminum SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article; Proceedings Paper CT 12th Meeting of the International Conference on the Strength of Materials (ICSMA 12) CY AUG 27-SEP 01, 2000 CL ASILOMAR, CALIFORNIA DE structure; twin dislocations; aluminum ID GRAIN-BOUNDARIES; ELECTRON-MICROSCOPY; ATOMIC-STRUCTURE; INTERFACES; COPPER; AG AB The structure and motion via climb of 1/3 <111> twin dislocations along a coherent twin boundary in aluminum are examined via a combination of high resolution transmission electron microscopy (HRTEM) and computer simulation. Climb of these defects increases the thickness of the twin and is a possible alternative to the more familiar glide mechanism. Detailed analysis of the observed defect structure and comparison with atomistic modeling shows that the 1/3 <111> twin dislocations exist in a dissociated configuration. This structure can be interpreted as the relaxation of the 1/3<111> dislocation into two dislocations. a Shockley partial and a stair-rod dislocation. which are separated by a short segment of stacking fault. The atomistic mechanism of the climb of the dislocations is analyzed. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Sandia Natl Labs, Livermore, CA 94551 USA. RP Foiles, SM (reprint author), Sandia Natl Labs, Mail Stop 1411,POB 5800, Albuquerque, NM 87185 USA. OI Foiles, Stephen/0000-0002-1907-454X NR 20 TC 13 Z9 14 U1 4 U2 15 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 PY 2001 VL 319 SI SI BP 102 EP 106 DI 10.1016/S0921-5093(01)01112-1 PG 5 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 510ME UT WOS:000173211200017 ER PT J AU Krenn, CR Roundy, D Morris, JW Cohen, ML AF Krenn, CR Roundy, D Morris, JW Cohen, ML TI Ideal strengths of bcc metals SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article; Proceedings Paper CT 12th Meeting of the International Conference on the Strength of Materials (ICSMA 12) CY AUG 27-SEP 01, 2000 CL ASILOMAR, CALIFORNIA DE ideal strength; bcc ductile-brittle transition; pencil-glide ID COPPER AB We present ab initio ideal strength calculations in body-centered cubic (bcc) tungsten for 'pencil-glide' slip on {110}, {112}, and {123} planes and for the {100} cleavage strength. We use these results to analyze the tensile and shear strengths of other bcc metals. In all bee metals, the minimum shear strength on any plane containing <111> is approximate to0.11/S-<111>, where S-<111> is the elastic compliance for any shear in a <111> direction. The ideal cleavage strength on {100} for many bee metals is approximate to0.083/s(11) where s(11) is the single crystal elastic compliance. Comparison of the ideal shear and tensile strengths offers a measure of the inherent ductility or brittleness of a material. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Calif Berkeley, Dept Mat Sci & Engn, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Lawrence Berkeley Natl Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Krenn, CR (reprint author), Univ Calif Berkeley, Dept Mat Sci & Engn, Berkeley, CA 94720 USA. NR 20 TC 72 Z9 73 U1 3 U2 30 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 PY 2001 VL 319 SI SI BP 111 EP 114 DI 10.1016/S0921-5093(01)00998-4 PG 4 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 510ME UT WOS:000173211200019 ER PT J AU Lin, K Chrzan, DC AF Lin, K Chrzan, DC TI Boundary conditions for dislocation core structure studies: application to the 90 degrees partial dislocation in silicon SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article; Proceedings Paper CT 12th International Conference on the Strength of Materials (ICSMA 12) CY AUG 27-SEP 01, 2000 CL ASILOMAR, CA DE dislocation; core; silicon; elasticity; boundary conditions ID BCC SINGLE-CRYSTALS; AB-INITIO; SIMULATION AB The effects of boundary conditions on studies of dislocation cores are examined, using the 90degrees partial dislocation in Si as an illustration. The relative stability of two possible reconstructions of the core are explored using periodic supercell calculations and cylindrical boundary conditions and the results compared. It is argued that the stable core structure depends systematically on the stress field experienced by the dislocation, and that this dependence can be quantified effectively using a combination of periodic supercells and elasticity theory. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Calif Berkeley, Dept Mat Sci & Mineral Engn, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Ernest Orlando Lawrence Berkeley Natl Lab, Div Sci Mat, Berkeley, CA 94720 USA. RP Univ Calif Berkeley, Dept Mat Sci & Mineral Engn, 577 Evans Hall MS 1760, Berkeley, CA 94720 USA. EM dcchrzan@socrates.berkeley.edu NR 16 TC 5 Z9 5 U1 1 U2 3 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 PY 2001 VL 319 SI SI BP 115 EP 118 DI 10.1016/S0921-5093(01)00940-6 PG 4 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 510ME UT WOS:000173211200020 ER PT J AU Yang, LH Moriarty, JA AF Yang, LH Moriarty, JA TI Kink-pair mechanisms for a/2 < 111 > screw dislocation motion in bcc tantalum SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article; Proceedings Paper CT 12th Meeting of the International Conference on the Strength of Materials (ICSMA 12) CY AUG 27-SEP 01, 2000 CL ASILOMAR, CALIFORNIA DE Green's function; kink nucleation; kink pair; anti-phase defect; screw dislocation ID INTERATOMIC POTENTIALS; ATOMISTIC SIMULATIONS; BOUNDARY-CONDITIONS; METALS AB The structure, energetics, and multiplicity of kinks on an a/2 <111> screw dislocation in bcc Ta have been studied in detail via atomistic computer simulation, using quantum-based multi-ion interatomic potentials derived from model generalized pseudopotential theory (MGPT) together with a robust Green's function simulation technique. The stable core structure of the rigid screw dislocation is predicted to be weakly polarized and spread out on three {110} planes in <112> directions, with two energetically equivalent configurations. This double degeneracy leads to the possibility of anti-phase defects forming on the dislocation line as well multiple kinks and kink pairs. The zero-stress formation energies of 16 possible kink-pair configurations for bcc Ta have been calculated and are in the range 0.67-1.84 eV. The lowest kink-pair energy of the perfect screw is in good agreement with the best current empirical estimate. Under an applied stress, the corresponding kink-kink interaction energy displays a elastic attraction when the separation;. is larger than 7b = 20Angstrom. while the stress needed to maintain the kink pair varies as lambda(-1.5). (C) 2001 Elsevier Science B.V. All rights reserved. C1 Lawrence Livermore Natl Lab, Phys Directorate, Livermore, CA 94551 USA. RP Yang, LH (reprint author), Lawrence Livermore Natl Lab, Phys Directorate, Livermore, CA 94551 USA. NR 16 TC 10 Z9 10 U1 0 U2 8 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 PY 2001 VL 319 SI SI BP 124 EP 129 DI 10.1016/S0921-5093(01)01020-6 PG 6 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 510ME UT WOS:000173211200022 ER PT J AU Wright, WJ Schwarz, RB Nix, WD AF Wright, WJ Schwarz, RB Nix, WD TI Localized heating during serrated plastic flow in bulk metallic glasses SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article; Proceedings Paper CT 12th Meeting of the International Conference on the Strength of Materials (ICSMA 12) CY AUG 27-SEP 01, 2000 CL ASILOMAR, CALIFORNIA DE adiabatic heating; amorphous metal; metallic glass; serrated flow ID AMORPHOUS-ALLOYS; ZR41.2TI13.8CU12.5NI10.0BE22.5 AB We have studied the serrated plastic flow observed in Zr40Ti14Ni10Cu12Be24 and Pd40Ni40P20 bulk metallic glass alloys tested in uniaxial compression. Quantitative measurements with sufficient temporal resolution to record the fine-scale structure of the data are reported. These data are used to predict temperature increases in single shear bands due to local adiabatic heating caused by the work done on the sample during plastic deformation. Since the predicted temperature increases are on the order of only a few degrees Kelvin, it seems unlikely that localized heating is the primary cause of flow localization, Instead, changes in viscosity associated with increased free volume in the shear band seem more consistent with experiment. Substantial shear band heating is, however, predicted for final failure, as corroborated by evidence of melting on the fracture surface. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Stanford Univ, Dept Mat Sci & Engn, Stanford, CA 94305 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Wright, WJ (reprint author), Stanford Univ, Dept Mat Sci & Engn, 41B Escondido Mall,Bldg 550, Stanford, CA 94305 USA. OI Wright, Wendelin/0000-0001-6493-6025 NR 16 TC 223 Z9 236 U1 7 U2 56 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 PY 2001 VL 319 SI SI BP 229 EP 232 DI 10.1016/S0921-5093(01)01066-8 PG 4 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 510ME UT WOS:000173211200045 ER PT J AU Wittmann, M Wu, D Baker, I George, EP Heatherly, L AF Wittmann, M Wu, D Baker, I George, EP Heatherly, L TI The role of edge and screw dislocations on hydrogen embrittlement of Fe-40Al SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article; Proceedings Paper CT 12th Meeting of the International Conference on the Strength of Materials (ICSMA 12) CY AUG 27-SEP 01, 2000 CL ASILOMAR, CALIFORNIA DE FeAl; environment; dislocations; single crystal ID ROOM-TEMPERATURE DUCTILITY; B2-ORDERED IRON ALUMINIDES; ENVIRONMENTAL EMBRITTLEMENT; SINGLE-CRYSTALS; STRAIN-RATE; FEAL; FRACTURE; BORON; ALLOYS AB Tensile tests were performed in air and vacuum on Fe-40Al single crystals oriented so that predominately edge or screw dislocations accommodated the plastic strain. It was found for both orientations that ductility was less in air than in vacuum. However. no discernible correlation was found between the character of the dislocations, and the effect of environment. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Dartmouth Coll, Thayer Sch Engn, Hanover, NH 03755 USA. Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Baker, I (reprint author), Dartmouth Coll, Thayer Sch Engn, Hanover, NH 03755 USA. RI George, Easo/L-5434-2014 NR 20 TC 4 Z9 4 U1 0 U2 7 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 PY 2001 VL 319 SI SI BP 352 EP 355 DI 10.1016/S0921-5093(01)01060-7 PG 4 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 510ME UT WOS:000173211200071 ER PT J AU George, EP McKamey, CG Ohriner, EK Lee, EH AF George, EP McKamey, CG Ohriner, EK Lee, EH TI Deformation and fracture of iridium: microalloying effects SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article; Proceedings Paper CT 12th Meeting of the International Conference on the Strength of Materials (ICSMA 12) CY AUG 27-SEP 01, 2000 CL ASILOMAR, CALIFORNIA DE brittle-ductile transition; grain boundary; strain rate; iridium; alloying effects ID NI3AL; DUCTILITY; BEHAVIOR; ADDITIONS; ALLOYS AB The effects of Ce and Th doping (20-50 wppm) on the mechanical properties of Ir alloys were investigated. At both low (similar to 10(-3) s(-1)) and high (similar to 10(3) s(-1)) strain rates. the Ce + Th doped alloys undergo a transition from brittle intergranular (plus some transgranular) fracture at low temperature to ductile transgranular fracture at elevated temperature. The ductile-brittle transition temperature (DBTT) is similar to400 K higher at the higher strain rate. Grain size and grain-boundary cohesion both affect the ductility of Ir alloys. Cerium and thorium. when added together, refine grain size more effectively than when Th is added by itself (especially at high temperatures). Their effect on grain-boundary cohesion is similar to that of Th by itself. At low strain rates ( similar to 10(-3) s(-1)), the strength and ductility of alloys doped with Th were similar to those of alloys doped with both Th and Ce. The brittle-ductile transition appears to be related to a change from high work hardening rate at low temperature to low work hardening rate at elevated temperature. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP George, EP (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, POB 2008, Oak Ridge, TN 37831 USA. RI George, Easo/L-5434-2014 NR 31 TC 17 Z9 19 U1 1 U2 8 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 PY 2001 VL 319 SI SI BP 466 EP 470 DI 10.1016/S0921-5093(01)01082-6 PG 5 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 510ME UT WOS:000173211200096 ER PT J AU Schaff, O Schmid, AK Bartelt, NC de la Figuera, J Hwang, RQ AF Schaff, O Schmid, AK Bartelt, NC de la Figuera, J Hwang, RQ TI In-situ STM studies of strain-stabilized thin-film dislocation networks under applied stress SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article; Proceedings Paper CT 12th Meeting of the International Conference on the Strength of Materials (ICSMA 12) CY AUG 27-SEP 01, 2000 CL ASILOMAR, CALIFORNIA DE thin films; dislocations; surface dynamics; surface phase transformation; surface elasticity; gold surfaces ID RECONSTRUCTION; AU(111); SURFACE; DOMAINS AB The effect of uniaxial applied stress on dislocation networks present in the atomic surface layer of Au(111) was studied. The measurements were made using a novel instrument combining ultrahigh vacuum scanned-probe microscopy with an in-situ stress-strain testing machine. The technique provides microscopic information. up to atomic resolution. about the large scale plasticity of surface layers under applied loads. The herringbone reconstruction of the Au(111) surface is a classic example of a strain stabilized dislocation network. We find that under 0.5% uniaxially applied compressive strain a dramatic restructuring of the network takes place. The three-fold orientational degeneracy of the system is removed and threading edge dislocations are annihilated. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Sandia Natl Labs, Livermore, CA 94550 USA. RP Schmid, AK (reprint author), Sandia Natl Labs, Livermore, CA 94550 USA. RI de la Figuera, Juan/E-7046-2010 OI de la Figuera, Juan/0000-0002-7014-4777 NR 11 TC 21 Z9 21 U1 0 U2 7 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 PY 2001 VL 319 SI SI BP 914 EP 918 DI 10.1016/S0921-5093(01)00977-7 PG 5 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 510ME UT WOS:000173211200186 ER PT J AU Jiang, JS Bader, SD AF Jiang, JS Bader, SD TI New thin film permanent magnets SO MATERIALS SCIENCE AND TECHNOLOGY LA English DT Article ID EXCHANGE-SPRING BEHAVIOR; REMANENCE ENHANCEMENT; 2-PHASE MAGNETS; MULTILAYERS; ANISOTROPY; SUPERLATTICES; COERCIVITY; BILAYERS; HARD AB An overview is provided of research on coupled hard/soft magnetic multilayers as model exchange-spring systems, with an emphasis on uncovering the fundamental magnetic reversal processes and the correlation between microstructure and magnetic properties. The goal is to illustrate the rich opportunities to understand and hopefully improve permanent magnets by utilising the principles of nanotechnology and the microscopic tools of the modern materials science. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. EM jiang@anl.gov RI Bader, Samuel/A-2995-2013 NR 36 TC 11 Z9 11 U1 0 U2 1 PU TAYLOR & FRANCIS LTD PI ABINGDON PA 2-4 PARK SQUARE, MILTON PARK, ABINGDON OR14 4RN, OXON, ENGLAND SN 0267-0836 EI 1743-2847 J9 MATER SCI TECH-LOND JI Mater. Sci. Technol. PD DEC PY 2001 VL 17 IS 12 BP 1491 EP 1499 PG 9 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 505DN UT WOS:000172896400001 ER PT J AU Thomas, SM AF Thomas, SM TI Shining light of coating technology SO MATERIALS WORLD LA English DT Article C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU I O M COMMUNICATIONS LTD INST MATERIALS PI LONDON PA 1 CARLTON HOUSE TERRACE, LONDON SW1Y 5DB, ENGLAND SN 0967-8638 J9 MATER WORLD JI Mater. World PD DEC PY 2001 VL 9 IS 12 BP 19 EP 19 PG 1 WC Materials Science, Ceramics; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 504UG UT WOS:000172873800026 ER PT J AU Sanders, PG Thompson, MO Renk, TJ Aziz, MJ AF Sanders, PG Thompson, MO Renk, TJ Aziz, MJ TI Liquid titanium solute diffusion measured by pulsed ion-beam melting SO METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE LA English DT Article ID METALS; ALLOYS; AL AB The diffusivities of Sri, Mo, Zr, and Hf in liquid Ti were determined by pulsed ion-beam melting of thin liquid layers. Time-resolved optical reflectance and one-dimensional heat-flow simulations were employed to determine the melt duration. The broadening of nearly Gaussian solute concentration-depth profiles was determined ex situ using Rutherford backscattering spectrometry. Solute diffusivities in the range of 5 to 9 X 10(-5) cm(2)/s were determined at temperatures in the range of 2200 to 2500 K. Calculations of buoyancy and Marangoni convection indicate that convective contamination is unlikely. C1 Ford Motor Co, Ford Res Lab, Dearborn, MI 48121 USA. Cornell Univ, Dept Mat Sci & Engn, Ithaca, NY 14853 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. Harvard Univ, Div Engn & Appl Sci, Cambridge, MA 02138 USA. RP Sanders, PG (reprint author), Ford Motor Co, Ford Res Lab, Dearborn, MI 48121 USA. OI Thompson, Michael/0000-0002-4933-009X NR 22 TC 6 Z9 6 U1 0 U2 3 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086 USA SN 1073-5623 J9 METALL MATER TRANS A JI Metall. Mater. Trans. A-Phys. Metall. Mater. Sci. PD DEC PY 2001 VL 32 IS 12 BP 2969 EP 2974 DI 10.1007/s11661-001-0171-1 PG 6 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 506EK UT WOS:000172956700005 ER PT J AU Pal, UB MacDonald, CJ Chiang, E Chernicoff, WC Chou, KC Van den Avyle, J Molecke, MA Melgaard, D AF Pal, UB MacDonald, CJ Chiang, E Chernicoff, WC Chou, KC Van den Avyle, J Molecke, MA Melgaard, D TI Behavior of ceria as an actinide surrogate in electroslag remelting and refining slags SO METALLURGICAL AND MATERIALS TRANSACTIONS B-PROCESS METALLURGY AND MATERIALS PROCESSING SCIENCE LA English DT Article AB Downsizing and decommissioning of nuclear facility operations is increasing the stockpile of various different grades of radioactive scrap iron (RSI). Disposal of this material not only represents significant resource and value lost but also necessitates long term monitoring for environmental compliance. The latter results in additional recurring expense. It is desirable to be able to decontaminate the RSI to a very low level that can be recycled or used for fabrication of containers for RSI disposal instead of using virgin metal to fabricate the container. Electroslag remelting and refining (ESR) is often used for decontaminating radioactive contaminated sources of scrap iron, such as stainless steel. Nonradioactive oxides of cerium are used to simulate the radioactive oxide contaminants of uranium and plutonium. The success of the ESR process is strongly dependent on having the right thermo-physical-and-chemical slag properties. In this article, we measured the following relevant slag properties: capacity to incorporate the radioactive contaminant (simulant), volatilization rate and volatile species, electrical conductivity, viscosity, surface tension, and slag-metal partition coefficient, as a function of temperature. The impact of these properties on the ESR decontamination process is discussed. C1 Boston Univ, Dept Mfg Engn, Boston, MA 02446 USA. Sandia Natl Labs, Liquid Met Proc Lab, Albuquerque, NM 87185 USA. RP Pal, UB (reprint author), Boston Univ, Dept Mfg Engn, Boston, MA 02446 USA. NR 11 TC 2 Z9 2 U1 1 U2 6 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086 USA SN 1073-5615 J9 METALL MATER TRANS B JI Metall. Mater. Trans. B-Proc. Metall. Mater. Proc. Sci. PD DEC PY 2001 VL 32 IS 6 BP 1119 EP 1128 DI 10.1007/s11663-001-0100-0 PG 10 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 507VR UT WOS:000173052400015 ER PT J AU Evans, LG Starr, RD Bruckner, J Reedy, RC Boynton, WV Trombka, JI Goldstein, JO Masarik, J Nittler, LR McCoy, TJ AF Evans, LG Starr, RD Bruckner, J Reedy, RC Boynton, WV Trombka, JI Goldstein, JO Masarik, J Nittler, LR McCoy, TJ TI Elemental composition from gamma-ray spectroscopy of the NEAR-Shoemaker landing site on 433 Eros SO METEORITICS & PLANETARY SCIENCE LA English DT Article ID SPECTROMETER AB Elemental composition and composition ratios derived from gamma-ray measurements collected by the NEAR-Shoemaker spacecraft while on the surface of 433 Eros are reported. Performance of the gamma-ray spectrometer (GRS) during cruise and orbit is reviewed. The best gamma-ray data were collected on the surface of Eros after the spacecraft's controlled descent on 2001 February 12. Methods used in spectral analysis, to convert peak areas to incident photons, and photons to elemental composition are described in some detail. The elemental abundance of K and the Mg/Si, Fe/Si, Si/O and Fe/O abundance ratios were determined. The Mg/Si and Si/O ratios and the K abundance are roughly chondritic, but the Fe/Si and Fe/O ratios are low compared to expected chondritic values. Three possible explanations for the apparent Fe depletion are considered. C1 Comp Sci Corp, Sci Programs, Lanham, MD 20706 USA. Catholic Univ Amer, Dept Phys, Washington, DC 20064 USA. Max Planck Inst Chem, D-55020 Mainz, Germany. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Arizona, Lunar & Planetary Lab, Tucson, AZ 85721 USA. NASA, Goddard Space Flight Ctr, Extraterr Phys Lab, Greenbelt, MD 20771 USA. Johns Hopkins Univ, Appl Phys Lab, Laurel, MD 20723 USA. Smithsonian Inst, Natl Museum Nat Hist, Dept Mineral Sci, Washington, DC 20560 USA. RP Evans, LG (reprint author), Comp Sci Corp, Sci Programs, Lanham, MD 20706 USA. NR 31 TC 41 Z9 41 U1 0 U2 3 PU METEORITICAL SOC PI FAYETTEVILLE PA DEPT CHEMISTRY/BIOCHEMISTRY, UNIV ARKANSAS, FAYETTEVILLE, AR 72701 USA SN 1086-9379 J9 METEORIT PLANET SCI JI Meteorit. Planet. Sci. PD DEC PY 2001 VL 36 IS 12 BP 1639 EP 1660 PG 22 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 513QG UT WOS:000173389200008 ER PT J AU Nittler, LR Starr, RD Lim, L McCoy, TJ Burbine, TH Reedy, RC Trombka, JI Gorenstein, P Squyres, SW Boynton, WV McClanahan, TP Bhangoo, JS Clark, PE Murphy, ME Killen, R AF Nittler, LR Starr, RD Lim, L McCoy, TJ Burbine, TH Reedy, RC Trombka, JI Gorenstein, P Squyres, SW Boynton, WV McClanahan, TP Bhangoo, JS Clark, PE Murphy, ME Killen, R TI X-ray fluorescence measurements of the surface elemental composition of asteroid 433 Eros SO METEORITICS & PLANETARY SCIENCE LA English DT Article ID EMISSION MEASURE; ORDINARY CHONDRITES; CALCIUM ABUNDANCE; SPECTROMETER; SPECTROSCOPY; TEMPERATURE; 433-EROS; MISSION AB We report major element ratios determined for the S-class asteroid 43 3 Eros using remote-sensing x-ray fluorescence spectroscopy with the near-Earth asteroid rendezvous Shoemaker x-ray spectrometer (XRS). Data analysis techniques and systematic errors are described in detail. Data acquired during five solar flares and during two extended "quiet Sun" periods are presented; these results sample a representative portion of the asteroid's surface. Although systematic uncertainties are potentially large, the most internally consistent and plausible interpretation of the data is that Eros has primitive Mg/Si, Al/Si, Ca/Si and Fe/Si ratios, closely similar to H or R chondrites. Global differentiation of the asteroid is ruled out. The S/Si ratio is much lower than that of chondrites, probably reflecting impact-induced volatilization and/or photo- or ion-induced sputtering of sulfur at the surface of the asteroid. An alternative explanation for the low S/Si ratio is that it reflects a limited degree of melting with loss of an FeS-rich partial melt. Size-sorting processes could lead to segregation of Fe-Ni metal from silicates within the regolith of Eros; this could indicate that the Fe/Si ratios determined by the x-ray spectrometer are not representative of the bulk Eros composition. C1 Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Catholic Univ Amer, Dept Phys, Washington, DC 20064 USA. Cornell Univ, Ithaca, NY 14853 USA. Smithsonian Inst, Natl Museum Nat Hist, Dept Mineral Sci, Washington, DC 20560 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Smithsonian Astrophys Observ, Cambridge, MA 02138 USA. Univ Arizona, Dept Planetary Sci, Tucson, AZ 85721 USA. SW Res Inst, San Antonio, TX 78228 USA. RP Nittler, LR (reprint author), Carnegie Inst Washington, Dept Terr Magnetism, 5241 Broad Branch Rd NW, Washington, DC 20015 USA. EM lrn@dtm.ciw.edu RI Lim, Lucy/C-9557-2012; Killen, Rosemary/E-7127-2012; OI Lim, Lucy/0000-0002-9696-9654; Reedy, Robert/0000-0002-2189-1303 NR 55 TC 67 Z9 69 U1 0 U2 5 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 1086-9379 J9 METEORIT PLANET SCI JI Meteorit. Planet. Sci. PD DEC PY 2001 VL 36 IS 12 BP 1673 EP 1695 PG 23 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 513QG UT WOS:000173389200010 ER PT J AU Kim, Y Hurst, GB AF Kim, Y Hurst, GB TI Study of matrix and polymer substrate in MALDI-TOF mass spectrometry of DNA SO MICROCHEMICAL JOURNAL LA English DT Article; Proceedings Paper CT 6th International Symposium on Advanced Analytical Techniques and Applications (AATA 2000) CY NOV 06-08, 2000 CL KYUNGNAM, SOUTH KOREA SP Coastal Resource & Environm Res Ctyr Instrumental Anal, Kyungnam Univ, Inst Basic Sci DE MALDI; DNA; polyacrylamide; 3-hydroxypicolinic acid ID NUCLEIC-ACID PROBES; SAMPLE SUPPORT; CAPILLARY ELECTROPHORESIS; PROTEINS; MEMBRANE; OLIGONUCLEOTIDES; POLYMORPHISMS; RESOLUTION; FRAGMENTS; PEPTIDES AB Protein matrices such as 3,5-dimethoxy-4-hydroxycinnamic acid (sinapinic acid, SA) and a-cyano-4-hydroxycinnamic acid (CHCA) tend to yield homogeneous dried spots. However, well known MALDI matrices for single- and double-stranded DNA such as 3-hydroxy picolinic acid (HPA) and picolinic acid (PA) forms the crystals at the rim of their spots with uneven distribution of matrix and DNA. This inhomogeneous deposition of DNA-doped matrix crystals at the MALDI spot requires a search for sweet spots. It is important to obtain homogeneous MALDI spots that yield signals not only from the periphery but the entire spot for automated, high throughput MALDI-TOF analysis of short DNA fragments. We have investigated the characteristics of MALDI matrices for DNA and presented a method for improving the homogeneity of MALDI samples by using polymer substrates such as linear polyacrylamide (LPA), poly(ethylene oxide) (PEO), methyl cellulose (MG) and Nafion. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Kyungnam Univ, Dept Chem, Masan, South Korea. Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Kim, Y (reprint author), Kyungnam Univ, Dept Chem, Masan, South Korea. NR 32 TC 8 Z9 8 U1 1 U2 7 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0026-265X J9 MICROCHEM J JI Microchem J. PD DEC PY 2001 VL 70 IS 3 BP 219 EP 228 DI 10.1016/S0026-265X(01)00136-9 PG 10 WC Chemistry, Analytical SC Chemistry GA 506EA UT WOS:000172955800010 ER PT J AU Miller, MK Russell, KF Kocik, J Keilova, E AF Miller, MK Russell, KF Kocik, J Keilova, E TI Atom probe tomography of 15Kh2MFA Cr-Mo-V steel surveillance specimens SO MICRON LA English DT Review DE pressure vessel steels; neutron irradiation; embrittlement; precipitation; grain boundary segregation; atom probe tomography ID PRESSURE-VESSEL STEELS AB An atom probe study has been performed on 15Kh2MFA base and 10KhMFT weld metal surveillance specimens from a VVER-440/213C reactor to investigate the mechanisms that produce embrittlement in low copper materials during service. The composition of the base metal was Fe-0.06 at.% Cu, 3.1% Cr, 0.34% V, 0.46% Mn, 0.35% Mo, 0.07% Ni, 0.34% Si, 0.74% C, 0.025% P, and 0.028% S. The base material was characterized after thermal aging for 10 years at 295 degreesC and after neutron irradiation at 270 degreesC for 10 years to a fluence of 1.0 X 10(25) m(-2) (E > 0.5 MeV). The ductile-to-brittle transition temperatures (DBTT) of the base metal were -49, -70 and 141 degreesC, for the unirradiated, thermally aged and neutron irradiated conditions, respectively. The composition of the weld metal was Fe-0.05 at.% Cu, 1.46% Cr, 0.22% V, 1.11% Mn, 0.29% Mo, 1.17% Si, 0.17% C, 0.02% P, and 0.029% S. The weld material was characterized after tempering for 18 h at 690 degreesC plus a simulated stress relief treatment of 43.5 h at 680 degreesC, after thermal aging for 5 years at 295 degreesC, and after neutron irradiation at 275 degreesC for 5 years to a fluence of 5.2 X 10(24) m(2) (E > 0.5 MeV). The DBTTs were 7, 11 and 123 degreesC, respectively, for these three conditions. A high number density of ultrafine manganese- and silicon-enriched regions was observed in both neutron-irradiated materials. Phosphorus segregation was observed at the VC-matrix interface and at grain boundaries. Published by Elsevier Science Ltd. C1 Oak Ridge Natl Lab, Div Met & Ceram, Microscopy & Microanalyt Sci Grp, Oak Ridge, TN 37831 USA. Rez Plc, Nucl Res Inst, Prague 25068, Czech Republic. RP Miller, MK (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, Microscopy & Microanalyt Sci Grp, POB 2008, Oak Ridge, TN 37831 USA. NR 9 TC 24 Z9 25 U1 0 U2 2 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0968-4328 J9 MICRON JI Micron PD DEC PY 2001 VL 32 IS 8 BP 749 EP 755 DI 10.1016/S0968-4328(00)00082-2 PG 7 WC Microscopy SC Microscopy GA 466TR UT WOS:000170662400007 ER PT J AU Miller, MK AF Miller, MK TI Contributions of atom probe tomography to the understanding of nickel-based superalloys SO MICRON LA English DT Review DE superalloys; atom probe tomography; precipitation; grain boundary segregation ID GRAIN-BOUNDARY MICROCHEMISTRY; ASTROLOY; APFIM AB Atom probe tomography enables atomic level microstructural characterization to be performed on complex engineering materials such as superalloys. The technique provides information on the size, morphology and compositions of coexisting phases, the solute partitioning of the elements between the phases, and solute segregation to interfaces and grain boundaries. This information leads to a more complete understanding of nickel-based superalloys. The types of atomic level information that may be obtained with atom probe tomography are illustrated with examples of the formation of fine gamma precipitates within the central region of the gamma' phase in PW 1480, the evolution of the dual gamma'/gamma " nature of secondary precipitates in alloy 718, the interphase precipitation of the gamma' phase at the primary gamma "-gamma interface in alloy 718, and the quantification of the level and spatial extent of the boron segregation at grain boundaries in a nickel-molybdenum superalloy. Published by Elsevier Science Ltd. C1 Oak Ridge Natl Lab, Div Met & Ceram, Microscopy & Microanalyt Sci Grp, Oak Ridge, TN 37831 USA. RP Miller, MK (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, Microscopy & Microanalyt Sci Grp, POB 2008, Oak Ridge, TN 37831 USA. NR 18 TC 43 Z9 47 U1 2 U2 31 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0968-4328 J9 MICRON JI Micron PD DEC PY 2001 VL 32 IS 8 BP 757 EP 764 DI 10.1016/S0968-4328(00)00083-4 PG 8 WC Microscopy SC Microscopy GA 466TR UT WOS:000170662400008 ER PT J AU Terrill, WA AF Terrill, WA TI The political mythology of the Battle of Karameh SO MIDDLE EAST JOURNAL LA English DT Article AB The March 1968 battle of Karameh was a conflict with limited military importance fought primarily between the Israelis and Jordanians with some Palestinian guerrilla participation. Despite the limited guerrilla role, this battle, nevertheless, became a pivotal event in the emergence of new Palestinian political identity. It also became an important case study in the role of political mythology in supporting emerging and evolving nationalisms. Demoralized Palestinians seized upon the heroic image of the small group of Palestinian guerrillas who had fought bravely during the battle. The myth about Karameh grew, for the most part, spontaneously because it met critical human needs among the Palestinians. This growth also occurred despite Jordanian and Israeli efforts to provide alternative descriptions of the same events. Distortions created by this myth and the Israeli countermyth can non be assessed using new and more candid sources. Additionally, Karameh also provides an interesting example of how political myths erode as they become less relevant to changing needs among the community they previously served. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Terrill, WA (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 38 TC 2 Z9 2 U1 1 U2 1 PU MIDDLE EAST INSTITUTE PI WASHINGTON PA 1761 N STREET NW, CIRCULATION DEPT, WASHINGTON, DC 20036-2882 USA SN 0026-3141 J9 MIDDLE EAST J JI Middle East J. PD WIN PY 2001 VL 55 IS 1 BP 91 EP 111 PG 21 WC Area Studies SC Area Studies GA 397WT UT WOS:000166721400005 ER PT J AU Trautz, RC Wang, JSY AF Trautz, RC Wang, JSY TI Evaluation of seepage into an underground opening using small-scale field experiments, Yucca Mountain, Nevada SO MINING ENGINEERING LA English DT Article ID CAPILLARY BARRIERS AB To evaluate the potential for water seeping into an underground opening, a 9-m- (30-ft-) long drift was constructed in the unsaturated fractured tuff at Yucca Mountain. Forty seepage tests were performed by releasing finite volumes of water at a constant rate into short test intervals located in boreholes positioned above the drift. The seepage threshold flux, defined as the liquid-release flux at and below which water will not drip into the opening, was determined for 10 test intervals. The seepage data, observations and model results indicate that a seepage threshold exists because a capillary barrier diverts water around the opening. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Trautz, RC (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. NR 11 TC 5 Z9 5 U1 0 U2 0 PU SOC MINING METALLURGY EXPLORATION INC PI LITTLETON PA 8307 SHAFFER PARKWAY, LITTLETON, CO 80127 USA SN 0026-5187 J9 MIN ENG-LITTLETON JI Mining Eng. PD DEC PY 2001 VL 53 IS 12 BP 41 EP 44 PG 4 WC Mining & Mineral Processing SC Mining & Mineral Processing GA 502QE UT WOS:000172753600030 ER PT J AU Laouar, A Glesne, D Huberman, E AF Laouar, A Glesne, D Huberman, E TI Protein kinase C-beta, fibronectin, alpha(5)beta(1)-integrin, and tumor necrosis factor-alpha are required for phorbol diester-induced apoptosis in human myeloid leukemia cells SO MOLECULAR CARCINOGENESIS LA English DT Article DE caspase; ceramide; differentiation; HL-60 cells; phorbol 12-myristate 13-acetate; programmed cell death ID ESTER-INDUCED DIFFERENTIATION; BREAST-CANCER CELLS; GENE-EXPRESSION; MACROPHAGE DIFFERENTIATION; MONOCYTIC DIFFERENTIATION; SIGNALING PATHWAYS; PROMOTING AGENTS; FUNCTIONAL-ROLE; HL-60 CELLS; INDUCTION AB The human myeloid HL-60 cell line and its cell variant HL-525 were used to study signaling events leading to apoptosis induction by phorbol 12-myristate 13-acetate (PMA), an activator of protein kinase C (PKC) enzymes. Unlike parental cells, HL-525 cells are PKC-P deficient and resistant to PMA-induced apoptosis. These cells regain susceptibility to apoptosis induction after transfection with a PKC-P expression-vector. By using this vector and specific neutralizing monoclonal antibodies (mAbs), it was established that PMA-induced apoptosis also called for an interaction between cell-surface alpha (5)beta (1)-integrin and its deposited ligand fibronectin (FN), which is downstream of PKC-P activation. Experiments with mAbs, the PKC-P vector, and exogenous FN revealed that the next step entailed an interaction between secreted tumor necrosis factor-a and its type I receptor. By using a sphingomyelinase inhibitor, it was concluded that the subsequent step involved ceramide production. Moreover, a permeable ceramide was effective in inducing apoptosis in both HL-60 and HL-525 cells, and this induction was caspase-1 and/or -4 dependent because an inhibitor of these caspases abrogated the induced apoptosis. Based on these and related differentiation studies, we conclude that the above signaling events, the early ones in particular, are shared with PMA-induced macrophage differentiation in the HL-60 cells. It is likely that once these cells acquire their macrophage phenotype and perform their tasks, they become superfluous and are eliminated from the body by a self-triggered apoptotic process that involves our proposed signaling scheme. (C) 2001 Wiley-Liss, Inc. C1 Argonne Natl Lab, Biochip Technol Ctr, Gene Express & Func Grp, Argonne, IL 60439 USA. RP Huberman, E (reprint author), Argonne Natl Lab, Biochip Technol Ctr, Gene Express & Func Grp, 9700 S Cass Ave, Argonne, IL 60439 USA. FU NCI NIH HHS [CA 80826] NR 45 TC 18 Z9 18 U1 1 U2 1 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC, 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0899-1987 J9 MOL CARCINOGEN JI Mol. Carcinog. PD DEC PY 2001 VL 32 IS 4 BP 195 EP 205 DI 10.1002/mc.10012 PG 11 WC Biochemistry & Molecular Biology; Oncology SC Biochemistry & Molecular Biology; Oncology GA 498QP UT WOS:000172522200004 PM 11746831 ER PT J AU Tavares, GA Panepucci, EH Brunger, AT AF Tavares, GA Panepucci, EH Brunger, AT TI Structural characterization of the intramolecular interaction between the SH3 and guanylate kinase domains of PSD-95 SO MOLECULAR CELL LA English DT Article ID POSTSYNAPTIC DENSITY; MACROMOLECULAR STRUCTURES; STRUCTURE REFINEMENT; EXCITATORY SYNAPSES; DISCS-LARGE; PROTEIN; MEMBRANE; COMPLEX; CALMODULIN; BINDING AB PSD-95/SAP90 is a member of the MAGUK superfamily. In excitatory synapses, PSD-95 clusters receptors and ion channels at specific sites in the postsynaptic membrane and organizes downstream signaling and cytoskeletal molecules. We have determined the crystal structures of the apo and GMP-bound forms to 2.3 and 2.0 A resolutions, respectively, of a fragment containing the SH3, HOOK, and guanylate kinase (GK) domains of PSD-95. We observe an intramolecular interaction between the SH3 and GK domains involving the formation of a beta sheet including residues N- and C-terminal to the GK domain. Based on amino acid conservation and mutational data available in the literature, we propose that this intramolecular interaction is a common feature among MAGUK proteins. C1 Stanford Univ, Howard Hughes Med Inst, Stanford, CA 94305 USA. Stanford Univ, Dept Cellular & Mol Physiol, Stanford, CA 94305 USA. Stanford Univ, Dept Neurol & Neurol Sci, Stanford, CA 94305 USA. Stanford Univ, Stanford Synchrotron Radiat Lab, Stanford, CA 94305 USA. RP Brunger, AT (reprint author), Stanford Univ, Howard Hughes Med Inst, 1201 Welch Rd P210 MSLS, Stanford, CA 94305 USA. NR 59 TC 116 Z9 119 U1 0 U2 1 PU CELL PRESS PI CAMBRIDGE PA 1100 MASSACHUSETTS AVE,, CAMBRIDGE, MA 02138 USA SN 1097-2765 J9 MOL CELL JI Mol. Cell PD DEC PY 2001 VL 8 IS 6 BP 1313 EP 1325 DI 10.1016/S1097-2765(01)00416-6 PG 13 WC Biochemistry & Molecular Biology; Cell Biology SC Biochemistry & Molecular Biology; Cell Biology GA 505HR UT WOS:000172907800018 PM 11779506 ER PT J AU Liz-Marzan, LM Norris, DJ Bawendi, MG Betley, T Doyle, H Guyot-Sionnest, P Klimov, VI Kotov, NA Mulvaney, P Murray, CB Schiffrin, DJ Shim, M Sun, S Wang, C AF Liz-Marzan, LM Norris, DJ Bawendi, MG Betley, T Doyle, H Guyot-Sionnest, P Klimov, VI Kotov, NA Mulvaney, P Murray, CB Schiffrin, DJ Shim, M Sun, S Wang, C TI New aspects of nanocrystal research SO MRS BULLETIN LA English DT Editorial Material C1 Univ Vigo, Dept Phys Chem, Vigo, Spain. CALTECH, Pasadena, CA 91125 USA. Natl Univ Ireland Univ Coll Cork, Natl Microelect Res Ctr, Nanotechnol Grp, Cork, Ireland. Univ Chicago, Dept Phys, Chicago, IL 60637 USA. Univ Chicago, Dept Chem, Chicago, IL 60637 USA. Los Alamos Natl Lab, Los Alamos, NM USA. Oklahoma State Univ, Dept Chem, Stillwater, OK 74078 USA. Univ Melbourne, Sch Chem, Nanoparticle Lab, Parkville, Vic 3010, Australia. IBM Corp, TJ Watson Res Ctr, Div Res, Dept Phys Sci, Yorktown Hts, NY 10598 USA. Univ Liverpool, Liverpool L69 3BX, Merseyside, England. Stanford Univ, Stanford, CA 94305 USA. Univ Chicago, James Franck Inst, Chicago, IL 60637 USA. RP Liz-Marzan, LM (reprint author), Univ Vigo, Dept Phys Chem, Vigo, Spain. RI Shim, Moonsub/A-7875-2009; Norris, David/F-4022-2010; Doyle, Hugh/A-1859-2012; Liz-Marzan, Luis/B-8910-2011 OI Shim, Moonsub/0000-0001-7781-1029; Doyle, Hugh/0000-0002-1453-1887; Liz-Marzan, Luis/0000-0002-6647-1353 NR 0 TC 28 Z9 28 U1 1 U2 15 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DR, WARRENDALE, PA 15086 USA SN 0883-7694 J9 MRS BULL JI MRS Bull. PD DEC PY 2001 VL 26 IS 12 BP 981 EP + PG 4 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 502HD UT WOS:000172737200019 ER PT J AU McDaniel, B Sheng, HX Warner, DS Hedlund, LW Benveniste, H AF McDaniel, B Sheng, HX Warner, DS Hedlund, LW Benveniste, H TI Tracking brain volume changes in C57BL/6J and ApoE-deficient mice in a model of neurodegeneration: A 5-week longitudinal micro-MRI study SO NEUROIMAGE LA English DT Article ID TRANSIENT FOREBRAIN ISCHEMIA; TRANSGENIC MOUSE MODELS; DELAYED NEURONAL DEATH; NECROSIS-FACTOR-ALPHA; ALZHEIMERS-DISEASE; HUNTINGTONS-DISEASE; CEREBRAL-ISCHEMIA; RAT; HIPPOCAMPUS; DAMAGE AB Magnetic resonance imaging (MRI)-based volume measurements of brain structures are useful indicators of pending cognitive decline in humans suffering from neurodegenerative diseases. Transgenic mouse models that mimic the clinical conditions of these disorders have been developed. Noninvasive methods that can follow progression and regression of relevant pathology in these mice are therefore in great demand. In this study we tested whether high-resolution MRI (micro-MRI) in a mouse model of neurodegeneration (cerebral ischemia) could reliably track development of brain atrophy. We first established that diffusion imaging at a spatial resolution of 1.6 X 10(-3) mm(3) allowed superior visualization of forebrain, ventricles, and dorsal hippocampus in the mouse brain compared to either T2*- or Tl-weighted MR imaging. Using this predetermined protocol we subsequently scanned C56BL/6J (C57) and ApoE-deficient (ApoE(-/-)) mice before and after ischemia. Four groups were studied: C57/sham (n = 9), ApoE(-/-)/sham (n = 9), C57/ischemia (n = 9), and ApoE(-/-)/ischemia (n = 11). All mice received a baseline 3D diffusion scan. One week later C57/ischemia and ApoE-/-/ischemia mice were exposed to 10 min of ischemia and scanned again on the 3rd and 30th postischemic day. The C57/sham and ApoE(-/-)/sham mice served as controls and were scanned at corresponding time points. Diffusion images of ApoE(-/-)/ischemia mice on the 3rd postischemic day revealed multiple localized high signal intensity areas. An increase in ventricle and a decrease in dorsal hippocampal volumes (which included the associated cortex laterally) at 30 days confirmed brain atrophy in C57 mice after ischemia. Excessive mortality of ApoE(-/-)/ischemia mice restricted statistical analysis, but ventricle enlargement postischemia was demonstrated. Our results show that volume changes in the brain of a 30-g mouse can be tracked by micro-MRI in a model of neurodegeneration. Clearly the ability to follow progression of pathology in mice will greatly aid our understanding of neurodegenerative diseases and facilitate the many possibilities to intervene pharmacologically. (C) 2001 Academic Press. C1 Duke Univ, Med Ctr, Dept Radiol, Durham, NC 27710 USA. Duke Univ, Med Ctr, Dept Anesthesiol, Durham, NC 27710 USA. Brookhaven Natl Lab, Dept Med, Upton, NY 11973 USA. SUNY Stony Brook, Dept Anesthesiol, Stony Brook, NY 11794 USA. RP McDaniel, B (reprint author), Duke Univ, Med Ctr, Dept Radiol, Durham, NC 27710 USA. OI Hedlund, Laurence/0000-0001-5275-0397 FU NCRR NIH HHS [P41 RR05959] NR 30 TC 40 Z9 42 U1 0 U2 8 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 1053-8119 J9 NEUROIMAGE JI Neuroimage PD DEC PY 2001 VL 14 IS 6 BP 1244 EP 1255 DI 10.1006/nimg.2001.0934 PG 12 WC Neurosciences; Neuroimaging; Radiology, Nuclear Medicine & Medical Imaging SC Neurosciences & Neurology; Radiology, Nuclear Medicine & Medical Imaging GA 498RP UT WOS:000172524500002 PM 11707081 ER PT J AU Biegon, A Kerman, IA AF Biegon, A Kerman, IA TI Autoradiographic study of pre- and postnatal distribution of cannabinoid receptors in human brain SO NEUROIMAGE LA English DT Article ID MESSENGER-RNA LEVELS; RAT-BRAIN; PRENATAL EXPOSURE; FETAL GROWTH; MARIJUANA; BINDING; DELTA(9)-TETRAHYDROCANNABINOL; PREGNANCY; ALCOHOL; AGE AB Cannabinoid receptors have been characterized and localized in the brain of several species, including human. The pre- and postnatal distribution of human brain CB1 receptors was investigated using quantitative autoradiography with [H-3]CP55,940 as a ligand. Normal fetal brains (N = 8, gestational age 14-24 weeks) were obtained from voluntary abortions. Normal (drug and pathology free) adult human brains (N = 16, age 18-78) were obtained from the medical examiner's offices in New York City and Jaffa, Israel. Brains were stored frozen at -70 degreesC and sectioned (40 mum) at -15 degreesC. The radio-ligand (5 nM) was incubated with the sections for 3 h at room temperature. Washed and dried sections were exposed to tritium-sensitive film along with standards for 7-28 days and autoradiograms quantitated using NIH Image software. In the fetal human brain, low densities of THC-displaceable, region-specific binding could be observed as early as 14 weeks gestation. Receptor density increased slowly with gestational age but did not reach adult levels by the end of the second trimester (24 weeks gestation). In addition, the distribution pattern in the fetal brains was markedly different from the adult pattern. The most striking difference was the very low density of binding in the fetal caudate and putamen. In contrast, the globus pallidus pars medialis has almost-adult levels of cannabinoid receptors by 17-18 weeks gestation. The relatively low and regionally selective appearance of cannabinoid receptors in the fetal human brain may explain the relatively mild and selective nature of postnatal neurobehavioral deficits observed in infants exposed to cannabinoids in utero. (C) 2001 Academic Press. C1 Lawrence Berkeley Natl Lab, Funct Imaging Ctr, Berkeley, CA 94720 USA. RP Kerman, IA (reprint author), Lawrence Berkeley Natl Lab, Funct Imaging Ctr, Berkeley, CA 94720 USA. NR 43 TC 49 Z9 50 U1 1 U2 2 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 1053-8119 J9 NEUROIMAGE JI Neuroimage PD DEC PY 2001 VL 14 IS 6 BP 1463 EP 1468 DI 10.1006/nimg.2001.0939 PG 6 WC Neurosciences; Neuroimaging; Radiology, Nuclear Medicine & Medical Imaging SC Neurosciences & Neurology; Radiology, Nuclear Medicine & Medical Imaging GA 498RP UT WOS:000172524500023 PM 11707102 ER PT J AU Beller, DE Polansky, GF Anghaie, S Besenbruch, G Parish, TA AF Beller, DE Polansky, GF Anghaie, S Besenbruch, G Parish, TA TI Reports of DEC's death "greatly exaggerated" SO NUCLEAR ENGINEERING INTERNATIONAL LA English DT Article C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Beller, DE (reprint author), Los Alamos Natl Lab, Los Alamos, NM 87545 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU WILMINGTON PUBLISHING PI SIDCUP PA WILMINGTON HOUSE, MAIDSTONE RD, FOOTS CRAY, SIDCUP DA14 SHZ, KENT, ENGLAND SN 0029-5507 J9 NUCL ENG INT JI Nucl. Eng. Int. PD DEC PY 2001 VL 46 IS 569 BP 34 EP 36 PG 3 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 505AR UT WOS:000172889200029 ER PT J AU Takenaga, H Sakasai, A Kubo, H Asakura, N Schaffer, MJ Petrie, TW Mahdavi, MA Baker, DR Allen, SL Porter, GD Rognlien, TD Rensink, ME Stotler, DP Karney, CFF AF Takenaga, H Sakasai, A Kubo, H Asakura, N Schaffer, MJ Petrie, TW Mahdavi, MA Baker, DR Allen, SL Porter, GD Rognlien, TD Rensink, ME Stotler, DP Karney, CFF TI Study of particle pumping characteristics for different pumping geometries in JT-60U and DIII-D divertors SO NUCLEAR FUSION LA English DT Article ID PARAMETERS AB Particle pumping characteristics were compared between pumping from the inner side private flux region (IPP) and pumping from both sides of the private flux region (BPP) in the JT-60U W shaped divertor, and between JT-60U IPP and pumping in the DIII-D lower baffled divertor. The pumping flux for BPP is smaller than that for IPP by about a factor of 2 with weak in-out asymmetry of recycling neutral flux and by a factor of 3.5-6.5 with strong in-out asymmetry. The reduction of the pumping flux for BPP is consistent with Monte Carlo simulations, where backflow at the outer pumping slot is observed due to in-out recycling asymmetry. The pumping flux in DIII-D at I-p = 0.8 MA and B-T = 1.6 T is comparable to or smaller than that for JT-60U IPP at I-p = 1.0 MA B-T = 3.8 T and I-p = 1.5 MA, B-T = 3.5 T in the same density regime. In the DIII-D divertor with pumping from the private flux region, the pumping flux decreases with increasing in-out asymmetry. The pumping flux normalized by the integrated D-alpha emission over the whole plasma exhibits a similar dependence on the distance between the pumping slot and the strike point in JT-60U IPP and the DIII-D lower divertor with pumping through the outer divertor plasma region. C1 Japan Atom Energy Res Inst, Naka, Ibaraki 31101, Japan. Gen Atom Co, San Diego, CA USA. Lawrence Livermore Natl Lab, Livermore, CA USA. Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Takenaga, H (reprint author), Japan Atom Energy Res Inst, Naka, Ibaraki 31101, Japan. RI Karney, Charles/C-1371-2013; Stotler, Daren/J-9494-2015 OI Karney, Charles/0000-0002-5006-5836; Stotler, Daren/0000-0001-5521-8718 NR 18 TC 18 Z9 18 U1 0 U2 3 PU INT ATOMIC ENERGY AGENCY PI VIENNA PA WAGRAMERSTRASSE 5, PO BOX 100, A-1400 VIENNA, AUSTRIA SN 0029-5515 J9 NUCL FUSION JI Nucl. Fusion PD DEC PY 2001 VL 41 IS 12 BP 1777 EP 1787 DI 10.1088/0029-5515/41/12/305 PG 11 WC Physics, Fluids & Plasmas SC Physics GA 505XJ UT WOS:000172940600005 ER PT J AU Mantsinen, MJ Jarvis, ON Kiptily, VG Sharapov, SE Alper, B Eriksson, LG Gondhalekar, A Heeter, RF McDonald, DC AF Mantsinen, MJ Jarvis, ON Kiptily, VG Sharapov, SE Alper, B Eriksson, LG Gondhalekar, A Heeter, RF McDonald, DC TI First observation of pT fusion in JET tritium plasmas with ICRF heating of protons SO NUCLEAR FUSION LA English DT Article ID TOKAMAK PLASMAS; DT PLASMAS; ION; RESONANCE AB High power ICRF heating of a hydrogen minority ion species in JET tritium plasmas has generated a total neutron rate that is about 40% larger than the 14 MeV neutron rate originating from fusion reactions between bulk tritium ions and deuterium minority ions. The T(p,n)(3) He fusion reaction, caused by ICRF accelerated protons, is identified as a source for producing the excess neutron emission. This reaction is endothermic and has a proton energy threshold of about I MeV and a peak cross-section at about 3.0 MeV. The presence of protons with such high energies is detected in gamma ray and high energy neutral particle analyser measurements and is also confirmed by ICRF modelling with the PION code. The fast proton energy content and the pT fusion reactivity as simulated by the PION code are compared with the experimental measurements when classical slowing down and confinement of ICRF accelerated protons are assumed in the simulations. C1 JET Joint Undertaking, Abingdon OX14 3EA, Oxon, England. Helsinki Univ Technol, Assoc Euratom Tekes, FIN-02150 Espoo, Finland. UKAEA Euratom Fus Assoc, Abingdon, Oxon, England. CEA Cadarache, Assoc Euratom CEA Fus, St Paul Les Durance, France. Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Mantsinen, MJ (reprint author), JET Joint Undertaking, Abingdon OX14 3EA, Oxon, England. RI Mantsinen, Mervi/B-8023-2016 OI Mantsinen, Mervi/0000-0001-9927-835X NR 27 TC 11 Z9 11 U1 2 U2 3 PU INT ATOMIC ENERGY AGENCY PI VIENNA PA WAGRAMERSTRASSE 5, PO BOX 100, A-1400 VIENNA, AUSTRIA SN 0029-5515 J9 NUCL FUSION JI Nucl. Fusion PD DEC PY 2001 VL 41 IS 12 BP 1815 EP 1822 DI 10.1088/0029-5515/41/12/309 PG 8 WC Physics, Fluids & Plasmas SC Physics GA 505XJ UT WOS:000172940600009 ER PT J AU Mansfield, DK Johnson, DW Grek, B Kugel, HW Bell, MG Bell, RE Budny, RV Bush, CE Fredrickson, ED Hill, KW Jassby, DL Maqueda, RJ Park, HK Ramsey, AT Synakowski, EJ Taylor, G Wurden, GA AF Mansfield, DK Johnson, DW Grek, B Kugel, HW Bell, MG Bell, RE Budny, RV Bush, CE Fredrickson, ED Hill, KW Jassby, DL Maqueda, RJ Park, HK Ramsey, AT Synakowski, EJ Taylor, G Wurden, GA TI Observations concerning the injection of a lithium aerosol into the edge of TFTR discharges SO NUCLEAR FUSION LA English DT Article ID FUSION-TEST-REACTOR; IMPURITY PELLET INJECTION; HIGHLY RADIATIVE PLASMAS; LOCAL TRANSPORT; TEMPERATURE PLASMAS; ENERGY CONFINEMENT; POLOIDAL ROTATION; MAGNETIC SHEAR; TOKAMAK; PERFORMANCE AB A new method of actively modifying the plasma-wall interaction was tested on the Tokamak Fusion Test Reactor. A laser was used to introduce a directed lithium aerosol into the discharge scrape-off layer. The lithium introduced in this fashion ablated and migrated preferentially to the limiter contact points. This allowed the plasma wall interaction to be influenced in situ and in real time by external means. Significant improvement in energy confinement and fusion neutron production rate as well as a reduction in the plasma Z(eff) have been documented in a neutral beam heated plasma. The introduction of a metallic aerosol into the plasma edge increased the internal inductance of the plasma column and also resulted in prompt heating of core electrons in ohmic plasmas. Preliminary evidence also suggests that the introduction of an aerosol leads to both edge poloidal velocity shear and edge electric field shear. C1 Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. Oak Ridge Natl Lab, Div Plasma Phys, Oak Ridge, TN USA. Los Alamos Natl Lab, Plasma Phys Grp, Los Alamos, NM USA. RP Mansfield, DK (reprint author), Princeton Univ, Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. RI Wurden, Glen/A-1921-2017 OI Wurden, Glen/0000-0003-2991-1484 NR 26 TC 76 Z9 77 U1 0 U2 11 PU INT ATOMIC ENERGY AGENCY PI VIENNA PA WAGRAMERSTRASSE 5, PO BOX 100, A-1400 VIENNA, AUSTRIA SN 0029-5515 J9 NUCL FUSION JI Nucl. Fusion PD DEC PY 2001 VL 41 IS 12 BP 1823 EP 1834 DI 10.1088/0029-5515/41/12/310 PG 12 WC Physics, Fluids & Plasmas SC Physics GA 505XJ UT WOS:000172940600010 ER PT J AU Federici, G Skinner, CH Brooks, JN Coad, JP Grisolia, C Haasz, AA Hassanein, A Philipps, V Pitcher, CS Roth, J Wampler, WR Whyte, DG AF Federici, G Skinner, CH Brooks, JN Coad, JP Grisolia, C Haasz, AA Hassanein, A Philipps, V Pitcher, CS Roth, J Wampler, WR Whyte, DG TI Plasma-material interactions in current tokamaks and their implications for next step fusion reactors SO NUCLEAR FUSION LA English DT Review ID ALCATOR-C-MOD; SCRAPE-OFF-LAYER; DIII-D TOKAMAK; RADIATION-ENHANCED SUBLIMATION; ASDEX-UPGRADE DIVERTOR; HYDROGEN ISOTOPE RETENTION; JOINT EUROPEAN TORUS; LASER-INDUCED FLUORESCENCE; IMPURITY PELLET INJECTION; CHEMICAL EROSION YIELDS AB The major increase in discharge duration and plasma energy in a next step DT fusion reactor will give rise to important plasma-material effects that will critically influence its operation, safety and performance. Erosion will increase to a scale of several centimetres from being barely measurable at a micron scale in today's tokamaks. Tritium co-deposited with carbon will strongly affect the operation of machines with carbon plasma facing components. Controlling plasma-wall interactions is critical to achieving high performance in present day tokamaks, and thus is likely to continue to be the case in the approach to practical fusion reactors. Recognition of the important consequences of these phenomena stimulated an internationally co-ordinated effort in the field of plasma-surface interactions supporting the Engineering Design Activities of the International Thermonuclear Experimental Reactor project. (ITER), and significant progress has been made in better understanding these issues. The paper reviews the underlying physical processes and the existing experimental database of plasma-material interactions both in tokamaks and laboratory simulation facilities for conditions of direct relevance to next step fusion reactors. Two main topical groups of interaction are considered: (i) erosion/redeposition from plasma sputtering and disruptions, including dust, and flake generation and (ii) tritium retention and removal. The use of modelling tools to interpret the experimental results and make projections for conditions expected in future devices is explained. Outstanding technical issues and specific recommendations on potential R&D avenues for their resolution are presented. C1 ITER Garching Joint Work Site, Garching, Germany. Princeton Univ, Plasma Phys Lab, Princeton, NJ 08544 USA. Argonne Natl Lab, Argonne, IL 60439 USA. Jet Joint Undertaking, Abingdon OX14 3EA, Oxon, England. Tore Supra, CEA Cadarache, St Paul Les Durance, France. Univ Toronto, Inst Aerosp Studies, Toronto, ON, Canada. Forschungszentrum, Inst Plasmaphys, Julich, Germany. MIT, Plasma Sci & Fus Ctr, Cambridge, MA 02139 USA. Max Planck Inst Plasma Phys, Garching, Germany. Sandia Natl Labs, Albuquerque, NM 87185 USA. Univ Calif San Diego, La Jolla, CA 92093 USA. RP ITER Garching Joint Work Site, Garching, Germany. EM federici@post.rzg.mpg.de NR 926 TC 735 Z9 743 U1 36 U2 235 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0029-5515 EI 1741-4326 J9 NUCL FUSION JI Nucl. Fusion PD DEC PY 2001 VL 41 IS 12R SI SI BP 1967 EP 2137 DI 10.1088/0029-5515/41/12/218 PG 171 WC Physics, Fluids & Plasmas SC Physics GA 518AW UT WOS:000173644700002 ER PT J AU Fissum, KG Bertozzi, W Chen, JP Dale, D Fenker, HC Gao, J Gavalya, A Gilad, S Leathers, CR Liyanage, N Michaels, RO Offermann, EAJM Segal, J Templon, JA Wechsler, R Wojtsekhowski, B Zhao, J AF Fissum, KG Bertozzi, W Chen, JP Dale, D Fenker, HC Gao, J Gavalya, A Gilad, S Leathers, CR Liyanage, N Michaels, RO Offermann, EAJM Segal, J Templon, JA Wechsler, R Wojtsekhowski, B Zhao, J TI Vertical drift chambers for the Hall A high-resolution spectrometers at Jefferson Lab SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article DE vertical drift chambers; charged-particle tracking system AB The High-Resolution Spectrometers in Hall A at Jefferson Laboratory have been instrumented with state-of-the-art Vertical Drift Chambers designed and constructed by the Nuclear Interactions Group at MITLNS in conjunction with the Physics Division at Jefferson Lab. These chambers rely on a unique, high cell-density design made possible by the absence of field-shaping wires. Each chamber has an inherent per-plane resolution for 5-cell cosmic-ray tracks of 145 mum FWHM when operated on the bench at -4.8kV with argon-isobutane gas, and 225 mum FWHM for 5-cell electron tracks when operated in the High-Resolution Spectrometer detector stack at - 4.0kV with argon-ethane gas. The design and construction facilitates wire placement and replacement to 50 mum, very low dark current, and no crosstalk. The detectors have been in almost continuous use since April 1996, providing reliable, high-resolution charged-particle tracking data for the Hall A physics program. A complete overview of this project is presented. (C) 2001 Elsevier Science B.V. All rights reserved. C1 MIT, Cambridge, MA 02139 USA. Thomas Jefferson Natl Accelerator Facil, Newport News, VA 23606 USA. RP Fissum, KG (reprint author), Lund Univ, Dept Phys, Box 118, SE-22100 Lund, Sweden. OI Templon, Jeffrey/0000-0002-3371-788X NR 19 TC 10 Z9 10 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 1 PY 2001 VL 474 IS 2 BP 108 EP 131 DI 10.1016/S0168-9002(01)00875-0 PG 24 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 498JQ UT WOS:000172506700002 ER PT J AU Freeman, J Green, D Ronzhin, A AF Freeman, J Green, D Ronzhin, A TI Hybrid photodiode crosstalk due to backscattered electrons SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article DE hybrid; photodiode; crosstalk; backscattered electrons AB The fraction of backscattering electrons are measured for 19 and 73 pixel Hybrid Photodiodes. The data obtained are in good agreement with calculations. A new method of HPD alignment is proposed and tested. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. RP Ronzhin, A (reprint author), Fermilab Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. NR 9 TC 0 Z9 0 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 1 PY 2001 VL 474 IS 2 BP 143 EP 150 DI 10.1016/S0168-9002(01)00874-9 PG 8 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 498JQ UT WOS:000172506700004 ER PT J AU Crawford, BE Bowman, JD Penttila, SI Roberson, NR AF Crawford, BE Bowman, JD Penttila, SI Roberson, NR TI A spin-transport system for a longitudinally polarized epithermal neutron beam SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article DE spin transport; polarized neutrons; parity violation ID PARITY-VIOLATION; COMPOUND-NUCLEUS; NONCONSERVATION; RESONANCES; APPARATUS AB The TRIPLE (Time Reversal and Parity at Low Energies) collaboration uses a polarized epithermal neutron beam and a capture gamma -ray detector to study parity violation in neutron-nucleus reactions. In order to preserve the spin polarization of the neutrons ab they travel the 60-m path to the target. the beam pipes are wrapped with wire to produce a solenoidal magnetic field of about 10 G along the beam direction. The flanges and bellows between sections of the beam pipe cause gaps in the windings which in turn produce radial fields that can depolarize the neutron spins, A computer code has been developed that numerically evaluates the effect of these gaps on the polarization. A measurement of the neutron depolarization for neutrons in the actual spin-transport system agrees with a calculation of the neutron depolarization for the TRIPLE system. Features that will aid in designing similar spin-transport systems are discussed. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Duke Univ, Durham, NC 27708 USA. Triangle Univ Nucl Lab, Durham, NC 27708 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Crawford, BE (reprint author), Gettysburg Coll, Dept Phys, Gettysburg, PA 17325 USA. NR 17 TC 0 Z9 0 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 1 PY 2001 VL 474 IS 2 BP 159 EP 171 DI 10.1016/S0168-9002(01)00881-6 PG 13 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 498JQ UT WOS:000172506700006 ER PT J AU Clough, RL AF Clough, RL TI High-energy radiation and polymers: A review of commercial processes and emerging applications SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Review ID ELECTRON-BEAM IRRADIATION; INDUCED GRAFT-POLYMERIZATION; INDUCED CROSS-LINKING; 2-PYRROLIDONE/ITACONIC ACID) HYDROGELS; MOLECULAR-WEIGHT POLYETHYLENE; LOW-DENSITY POLYETHYLENE; REINFORCED ADVANCED COMPOSITES; PRESSURE-SENSITIVE ADHESIVES; ETHYLENE-PROPYLENE RUBBER; STERILIZED EDIBLE FILMS AB Ionizing radiation has been found to be widely applicable in modifying the structure and properties of polymers, and can be used to tailor the performance of either bulk materials or surfaces. Fifty years of research in polymer radiation chemistry has led to numerous applications of commercial and economic importance. and work remains active in the application of radiation to practical uses involving polymeric materials. This paper provides a survey of radiation-processing methods of industrial interest, ranging from technologies already commercially well established, through innovations in the active R&D stage which show exceptional promise for future commercial use. Radiation-processing technologies are discussed under the following categories: cross-linking of plastics and rubbers, curing of coatings and inks. heat-shrink products. fiber-matrix composites. chain-scission for processing control, surface modification, grafting. hydrogels. sterilization, natural product enhancement, plastics recycling. ceramic precursors. electronic property materials. ion-track membranes and lithography for microdevice production. In addition to new technological innovations utilizing conventional gamma and e-beam Sources. a number of promising new applications make use of novel radiation types which include ion beams (heavy ions, light ions. highly focused microscopic beams and high-intensity pulses). soft X-rays which are focused, coherent X-rays (from a synchrotron) and e-beams which undergo scattering to generate patterns. Published by Elsevier Science B.V. C1 Sandia Natl Labs, Organ Mat Dept, Albuquerque, NM 87185 USA. RP Sandia Natl Labs, Organ Mat Dept, MS 0888, Albuquerque, NM 87185 USA. EM rlcloug@sandia.gov NR 375 TC 265 Z9 283 U1 14 U2 166 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X EI 1872-9584 J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD DEC PY 2001 VL 185 BP 8 EP 33 DI 10.1016/S0168-583X(01)00966-1 PG 26 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 505ZZ UT WOS:000172946600004 ER PT J AU Jahan, MS Thomas, DE King, MC Cooke, DW Bennett, BL Orler, EB Wrobleski, DA AF Jahan, MS Thomas, DE King, MC Cooke, DW Bennett, BL Orler, EB Wrobleski, DA TI Electron spin resonance study of oxidation in X-irradiated poly(ester urethane) containing nitroplasticizer SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 4th International Symposium on Ionizing Radiation and Polymers (IRaP 2000) CY SEP 24-28, 2000 CL GOUVIEUX CHANTILLE, FRANCE DE ESR; polyurethane; polymer; free radicals; BDNPA/BDNPF ID RELAXATION AB The effect of oxidation on X-irradiated Estane (R) 5703 containing nitroplasticizer (NP) has been examined by electron spin resonance (ESR) spectroscopy, and the results are compared to similar data previously obtained on pristine Estane (R) 5703. Although both specimens exhibit similar spectra immediately following X-irradiation, their decay upon exposure to air is quite different. The free radical concentration of the pristine specimen continuously decreases with time whereas the NP sample exhibits an initial decrease followed by a significant increase due to the growth of a newly-formed radical. Terminal species of the pristine and NP-Estane (R) 5703 samples are identified as peroxy and nitroxide radicals, respectively. Hyperfine coupling constants and g-values are extracted for the nitroxide radical and a tentative model is proposed to explain the reaction pathway leading to its production. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Memphis, Dept Phys, Memphis, TN 38152 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Jahan, MS (reprint author), Univ Memphis, Dept Phys, Memphis, TN 38152 USA. NR 14 TC 4 Z9 5 U1 1 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD DEC PY 2001 VL 185 BP 351 EP 354 DI 10.1016/S0168-583X(01)00853-9 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 505ZZ UT WOS:000172946600055 ER PT J AU Sillanpaa, J Koponen, IT Gronbech-Jensen, N AF Sillanpaa, J Koponen, IT Gronbech-Jensen, N TI A rate-equation model for the growth of metallic thin films in ion beam assisted deposition SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article DE surface growth; IBAD; MBE; rate equation ID ISLAND-SIZE DISTRIBUTIONS; SUBMONOLAYER EPITAXY; NUCLEATION; SURFACES; SIMULATIONS; DIFFUSION; DYNAMICS; BREAKUP AB We describe a simple and fast rate-equation model for surface growth during ion beam assisted metal-on-metal deposition. In terms of the rate coefficients the model describes how island detachment and breakup, adatom diffusion and interlayer transitions of adatoms affect the growth. Results from our model can be directly compared to experimental data, also for coverages of several layers. We identify parameter values corresponding to different modes of growth and locate the phase boundary between them as a function of temperature. We also show that in ideal layer-by-layer growth island size distributions retain the regular scaling form. Our model shows that in order to obtain thin films of good quality, both efficient detachment of adatoms and sufficiently fast interlayer transitions are needed. The results validate the approximations made in an earlier, more coarse-grained model. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Calif Davis, Dept Appl Sci, Davis, CA 95616 USA. Univ Helsinki, Dept Phys, FIN-00014 Helsinki, Finland. Lawrence Berkeley Natl Lab, NERSC, Berkeley, CA 94270 USA. RP Sillanpaa, J (reprint author), Univ Calif Davis, Dept Appl Sci, 1 Shields Ave 1840, Davis, CA 95616 USA. NR 28 TC 5 Z9 5 U1 2 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD DEC PY 2001 VL 184 IS 4 BP 523 EP 530 DI 10.1016/S0168-583X(01)00821-7 PG 8 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 505ZY UT WOS:000172946500007 ER PT J AU Verda, RD Tesmer, JR Maggiore, CJ Nastasi, M Bower, RW AF Verda, RD Tesmer, JR Maggiore, CJ Nastasi, M Bower, RW TI Geometric considerations relevant to hydrogen depth profiling by reflection elastic recoil detection analysis (vol 183, pg 391, 2001) SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Correction C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Calif Davis, Davis, CA 95616 USA. RP Verda, RD (reprint author), Los Alamos Natl Lab, Mail Stop G755, Los Alamos, NM 87545 USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD DEC PY 2001 VL 184 IS 4 BP 655 EP 655 DI 10.1016/S0168-583X(01)00976-4 PG 1 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 505ZY UT WOS:000172946500021 ER PT J AU Verda, RD Maggiore, CJ Tesmer, JR Misra, A Hoechbauer, T Nastasi, M Bower, RW AF Verda, RD Maggiore, CJ Tesmer, JR Misra, A Hoechbauer, T Nastasi, M Bower, RW TI Depth profiling of hydrogen in crystalline silicon using elastic recoil detection analysis SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Correction C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Calif Davis, Davis, CA 95616 USA. RP Verda, RD (reprint author), Los Alamos Natl Lab, Mail Stop G755, Los Alamos, NM 87545 USA. RI Misra, Amit/H-1087-2012 NR 2 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD DEC PY 2001 VL 184 IS 4 BP 656 EP 656 DI 10.1016/S0168-583X(01)00975-2 PG 1 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 505ZY UT WOS:000172946500022 ER PT J AU Loewen, EP Wilson, RD Hohorst, JK Kumar, AS AF Loewen, EP Wilson, RD Hohorst, JK Kumar, AS TI Preliminary FRAPCON-3Th steady-state fuel analysis of ThO2 and UO2 fuel mixtures SO NUCLEAR TECHNOLOGY LA English DT Article AB Recent investigations into the performance and economics of mixed thoria-urania (ThO2/UO2) fuel cycles in light water reactors indicate that there may be advantages to using these fuels at high burnups. The Idaho National Engineering and Environmental Laboratory (INEEL) modified FRAPCON-3, a U.S. Nuclear Regulatory Commission-sponsored software package developed by Pacific Northwest National Laboratory for use on mixed thoria-urania fuels. The modifications constituted the first stage of fuel performance evaluations supported by the Nuclear Energy Research Initiative (NERI) project titled Advanced Proliferation Resistant, Lower fe Cost, Uranium-Thorium Dioxide Fuels for Light Water Reactors. The goal of this NERI project is to develop mixed ThO2/UO2 fuels that can be operated to a relatively high burnup level in current and future commercial power reactors. This paper describes in detail the INEEL's modifications to the FRAPCON-3 thermal conductivity subroutine FTHCON and the techniques used to validate the modifications. The paper presents the general fuel design criteria used to model mixed thoria-urania fuel and a steady-state analysis of a mock thoria-urania fuel using the FRAPCON-3Th code. The paper also presents the data analyses for the mock thoria-urania fuel and offers suggestions for future upgrades and improvements to the code. C1 Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. Cooper Nucl Stn Nebraska Publ Power Dist, Brownville, NE USA. Univ Missouri, Rolla, MO 65409 USA. RP Loewen, EP (reprint author), Idaho Natl Engn & Environm Lab, POB 1625, Idaho Falls, ID 83415 USA. NR 11 TC 10 Z9 11 U1 0 U2 0 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60526 USA SN 0029-5450 J9 NUCL TECHNOL JI Nucl. Technol. PD DEC PY 2001 VL 136 IS 3 BP 261 EP 277 PG 17 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 493ZR UT WOS:000172253800002 ER PT J AU Karell, EJ Gourishankar, KV Smith, JL Chow, LS Redey, L AF Karell, EJ Gourishankar, KV Smith, JL Chow, LS Redey, L TI Separation of actinides from LWR spent fuel using molten-salt-based electrochemical processes SO NUCLEAR TECHNOLOGY LA English DT Article AB Results are presented of work done at Argonne National Laboratory to develop a molten-salt-based electrochemical technology for extracting uranium and transuranic elements from spent light water reactor fuel. In this process, the actinide oxides in the spent fuel are reduced using lithium at 650 degreesC in the presence of molten LiCl, yielding the corresponding actinides and Li2O. The actinides are then extracted from the reduction product by means of electrorefining. Associated with the reduction step is an ancillary salt-recovery step designed to electrochemically reduce the Li2O concentration of the salt and recover the lithium metal. Experiments were performed at the laboratory scale (50 to 150 g of fuel and 0.5 to 3.5 l of salt) and engineering scale (3.7 to 5.2 kg of fuel and 50 l of salt). Laboratory-scale experiments were designed to obtain information on the fundamental factors affecting process rates. Engineering-scale experiments were conducted to verify that the parameters controlling process scaleup are sufficiently understood, and to test equipment and operating concepts at or near full scale. All indications are that the electrochemical-based process should be workable at practical plant sizes. C1 Argonne Natl Lab, Div Chem Technol, Argonne, IL 60439 USA. RP Karell, EJ (reprint author), Argonne Natl Lab, Div Chem Technol, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 9 TC 24 Z9 24 U1 0 U2 3 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60526 USA SN 0029-5450 J9 NUCL TECHNOL JI Nucl. Technol. PD DEC PY 2001 VL 136 IS 3 BP 342 EP 353 PG 12 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 493ZR UT WOS:000172253800008 ER PT J AU Williams, DF Del Cul, GD Toth, LM Collins, ED AF Williams, DF Del Cul, GD Toth, LM Collins, ED TI The influence of Lewis acid/base chemistry on the removal of gallium by volatility from weapons-grade plutonium dissolved in molten chlorides SO NUCLEAR TECHNOLOGY LA English DT Article AB It has been proposed that GaCl3 can be removed by direct volatilization from a Pu-Ga alloy that is dissolved in a molten chloride salt. Although pure GaCl3 is quite volatile (boiling point: 201 degreesC), the behavior of GaCl3 dissolved in chloride salts is quite different because of solution effects and is critically dependent upon the composition of the solvent salt (i.e., its Lewis acid/base character). In this technical note, the behavior of gallium in prototypical Lewis acid and Lewis base salts is contrasted. It is found that gallium volatility is suppressed in basic melts and promoted in acidic melts. These results have an important influence on the potential for simple gallium removal in molten salt systems. C1 Oak Ridge Natl Lab, Div Chem Technol, Oak Ridge, TN 37831 USA. Electrochem Syst, Knoxville, TN 37922 USA. RP Williams, DF (reprint author), Oak Ridge Natl Lab, Div Chem Technol, POB 2008, Oak Ridge, TN 37831 USA. NR 10 TC 1 Z9 1 U1 0 U2 3 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60526 USA SN 0029-5450 J9 NUCL TECHNOL JI Nucl. Technol. PD DEC PY 2001 VL 136 IS 3 BP 367 EP 370 PG 4 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 493ZR UT WOS:000172253800010 ER PT J AU Vassilevski, P Woodward, CS AF Vassilevski, P Woodward, CS TI Special issue on 'Solution methods for large-scale non-linear problems' SO NUMERICAL LINEAR ALGEBRA WITH APPLICATIONS LA English DT Editorial Material C1 Lawrence Livermore Natl Lab, Ctr Appl Sci Comp, Livermore, CA 94550 USA. RP Vassilevski, P (reprint author), Lawrence Livermore Natl Lab, Ctr Appl Sci Comp, 7000 East Ave,Mail Stop L-560, Livermore, CA 94550 USA. RI Woodward, Carol/M-4008-2014 NR 0 TC 0 Z9 0 U1 0 U2 0 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 1070-5325 J9 NUMER LINEAR ALGEBR JI Numer. Linear Algebr. Appl. PD DEC PY 2001 VL 8 IS 8 BP 497 EP 497 DI 10.1002/nla.261 PG 1 WC Mathematics, Applied; Mathematics SC Mathematics GA 494KP UT WOS:000172281700001 ER PT J AU Lin, SY Chow, E Johnson, SG Joannopoulos, JD AF Lin, SY Chow, E Johnson, SG Joannopoulos, JD TI Direct measurement of the quality factor in a two-dimensional photonic-crystal microcavity SO OPTICS LETTERS LA English DT Article ID CAVITY; LASERS; DEFECT; MODE AB A new microcavity design is proposed and structures are realized with a two-dimensional photonic-crystal slab. The cavity consists of seven defect holes that encompass a hexagon and is designed to reduce vertical light leakage. From a direct transmission measurement, a Q value of 816 +/- 30 is achieved at A = 1.55 mum. This high-Q cavity will permit the realistic realization of spontaneous-emission modification and on-off optical switches. (C) 2001 Optical Society of America. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. MIT, Dept Phys, Cambridge, MA 02139 USA. RP Lin, SY (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 18 TC 38 Z9 39 U1 1 U2 1 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 1 PY 2001 VL 26 IS 23 BP 1903 EP 1905 DI 10.1364/OL.26.001903 PG 3 WC Optics SC Optics GA 498RW UT WOS:000172525100025 PM 18059732 ER PT J AU Uran, S Grimsditch, M Veal, BW Paulikas, AP AF Uran, S Grimsditch, M Veal, BW Paulikas, AP TI Optical investigation of the effects of substrate orientation on oxidation of single crystal beta-NiAl SO OXIDATION OF METALS LA English DT Article DE alumina scales; residual stress; single crystal; fluorescence; oxidation; NiAl; Raman ID GROWN ALUMINA SCALES; TRANSIENT OXIDATION; RESIDUAL-STRESS; ALPHA-ALUMINA; OXIDE SCALES; ALLOYS; ALPHA-AL2O3; SAPPHIRE; MICROSTRUCTURE; FLUORESCENCE AB Nondestructive optical techniques have been used to study the oxidation of low-index crystal faces of single-crystal beta -NiAl as a function of temperature. Using these techniques, residual stress, phase composition, and thickness of the scales were determined at various temperatures. The oxidation of the three low-index surfaces, (001), (110), and (111) exhibit discernible differences. Consistently lower stress values arc observed on (001) surfaces. Fluorescence and Raman results indicate a higher concentration of theta -Al(2)O(3) on (001) faces and lower concentrations on (111) faces at all temperatures between 800 and 1200 degreesC Although the residual stresses are higher on (110) faces, these are the only surfaces which maintain adherence up to 1450 degreesC All surfaces exhibit a stress anomaly between 1200 and 1250 degreesC. C1 Argonne Natl Lab, Argonne, IL 60439 USA. RP Uran, S (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 48 TC 5 Z9 5 U1 1 U2 3 PU SPRINGER/PLENUM PUBLISHERS PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0030-770X J9 OXID MET JI Oxid. Met. PD DEC PY 2001 VL 56 IS 5-6 BP 551 EP 569 DI 10.1023/A:1012501720653 PG 19 WC Metallurgy & Metallurgical Engineering SC Metallurgy & Metallurgical Engineering GA 503JP UT WOS:000172795600009 ER PT J AU Dasigi, V Mann, RC Protopopescu, VA AF Dasigi, V Mann, RC Protopopescu, VA TI Information fusion for text classification - an experimental comparison SO PATTERN RECOGNITION LA English DT Article DE text classification; features; latent semantic indexing; reference library; neural networks; information fusion AB This article reports on our experiments and results on the effectiveness of different feature sets and information fusion from some combinations of them in classifying free text documents into a given number of categories. We use different feature sets and integrate neural network learning into the method. The feature sets are based on the "latent semantics" of a reference library - a collection of documents adequately representing the desired concepts. We found that a larger reference library is not necessarily better. Information fusion almost always gives better results than the individual constituent feature sets. with certain combinations doing better than the others. (C) 2001 Published by Elsevier Science Ltd on behalf of Pattern Recognition Society. C1 So Polytechn State Univ, Dept Comp Sci, Marietta, GA 30060 USA. Oak Ridge Natl Lab, Div Life Sci, Oak Ridge, TN 37831 USA. Oak Ridge Natl Lab, Div Comp Sci & Math, Oak Ridge, TN 37831 USA. RP Dasigi, V (reprint author), So Polytechn State Univ, Dept Comp Sci, 1100 S Marietta Pkwy, Marietta, GA 30060 USA. NR 16 TC 10 Z9 11 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0031-3203 J9 PATTERN RECOGN JI Pattern Recognit. PD DEC PY 2001 VL 34 IS 12 BP 2413 EP 2425 DI 10.1016/S0031-3203(00)00171-0 PG 13 WC Computer Science, Artificial Intelligence; Engineering, Electrical & Electronic SC Computer Science; Engineering GA 482DA UT WOS:000171558500012 ER PT J AU Blishchenko, EY Kalinina, OA Sazonova, OV Khaidukov, SV Egorova, NS Surovoy, AY Philippova, MM Vass, AA Karelin, AA Ivanov, VT AF Blishchenko, EY Kalinina, OA Sazonova, OV Khaidukov, SV Egorova, NS Surovoy, AY Philippova, MM Vass, AA Karelin, AA Ivanov, VT TI Endogenous fragment of hemoglobin, neokyotorphin, as cell growth factor SO PEPTIDES LA English DT Article DE neokyotorphin; tissue-specific peptide pool; tumor cells; proliferation ID HUMAN-LUNG-CARCINOMA; NEO-KYOTORPHIN; NEUROPEPTIDES KYOTORPHIN; PROTEOLYTIC DEGRADATION; ANALGESIC PENTAPEPTIDE; BOVINE BRAIN; PROLIFERATION; ERYTHROCYTES; SECRETION; PEPTIDES AB It is shown that neokyotorphin (the alpha-globin fragment 137-141) stimulates proliferation of normal cells (murine embryonic fibroblasts, red bone marrow and spleen cells) and tumor cells (murine melanoma and transformed fibroblasts L929) in the absence or in the presence of fetal bovine serum. In contrast to serum deprivation conditions, the ability to potentiate L929 cell growth in the presence of fetal serum is strongly cell density dependent. The peptide also enhances the viability of L929 cells, murine embryonic fibroblasts and of the primary cultures of murine red bone marrow cells and splenocytes under serum-deprivation conditions for at least 72 h. The results of flow cytometry analysis suggest that the effect of neokyotorphin on survival of L929 cells in serum-free culture medium is due to maintenance of cell proliferation in the absence of growth factors. Along with cell cycle progression the peptide induces reversible reduction of L929 cell size. (C) 2001 Elsevier Science Inc. All rights reserved. C1 Russian Acad Sci, Shemyakin Ovchinnikov Inst Bioorgan Chem, Moscow 117871, Russia. Oak Ridge Natl Lab, Oak Ridge, TN USA. RP Blishchenko, EY (reprint author), Russian Acad Sci, Shemyakin Ovchinnikov Inst Bioorgan Chem, Ul Miklukho Maklaya 16-10,GSP 7, Moscow 117871, Russia. NR 21 TC 10 Z9 11 U1 0 U2 0 PU ELSEVIER SCIENCE INC PI NEW YORK PA 360 PARK AVE SOUTH, NEW YORK, NY 10010-1710 USA SN 0196-9781 J9 PEPTIDES JI Peptides PD DEC PY 2001 VL 22 IS 12 BP 1999 EP 2008 DI 10.1016/S0196-9781(01)00565-4 PG 10 WC Biochemistry & Molecular Biology; Endocrinology & Metabolism; Pharmacology & Pharmacy SC Biochemistry & Molecular Biology; Endocrinology & Metabolism; Pharmacology & Pharmacy GA 512DA UT WOS:000173304800008 PM 11786183 ER PT J AU Sadoc, A Kim, JY Kelton, KF AF Sadoc, A Kim, JY Kelton, KF TI Extended X-ray absorption fine-structure study of the hydrogen location in a Ti-Zr-Ni icosahedral quasicrystal and a 1/1 bcc crystal approximant SO PHILOSOPHICAL MAGAZINE A-PHYSICS OF CONDENSED MATTER STRUCTURE DEFECTS AND MECHANICAL PROPERTIES LA English DT Article ID QUASI-CRYSTALS; PHASE; ORDER; DIFFRACTION AB Extended X-ray absorption fine-structure measurements have been performed on Ti-Zr-Ni alloys using the Dispositif de Collision dans l'Igloo synchrotron radiation facility. Both a multigrained icosahedral quasicrystal and a 1/1 bcc polycrystalline approximant were studied. Alloys hydrogenated to a hydrogen-to-metal ratio of 1.7 for the icosahedral phase and 1.4 for the crystalline phase were also studied. The local atomic structures, which are different around the different types of atom, titanium, zirconium and nickel, are very similar in the non-hydrogenated alloys, crystal or quasicrystal. Drastic changes are observed in the local order in both hydrogenated alloys with modifications of distances and an increase in the disorder. Moreover, these modifications are slightly different in the 1/1 and icosahedral alloys after hydrogenation. C1 Univ Cergy Pontoise, Lab Phys Mat & Surfaces, F-95031 Neuville Sur Oise, Cergy Pontoise, France. Ctr Univ Paris Sud, Lab Utilisat Rayonnement Electromagnet, CNRS, MENESR,Commissariat Energie Atom, F-91898 Orsay, France. Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. Washington Univ, Dept Phys, St Louis, MO 63130 USA. RP Sadoc, A (reprint author), Univ Cergy Pontoise, Lab Phys Mat & Surfaces, F-95031 Neuville Sur Oise, Cergy Pontoise, France. NR 20 TC 9 Z9 9 U1 0 U2 0 PU TAYLOR & FRANCIS LTD PI LONDON PA 11 NEW FETTER LANE, LONDON EC4P 4EE, ENGLAND SN 0141-8610 J9 PHILOS MAG A JI Philos. Mag. A-Phys. Condens. Matter Struct. Defect Mech. Prop. PD DEC PY 2001 VL 81 IS 12 BP 2911 EP 2924 PG 14 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Physics, Applied; Physics, Condensed Matter SC Materials Science; Metallurgy & Metallurgical Engineering; Physics GA 495NV UT WOS:000172348000011 ER PT J AU Dippo, P AF Dippo, P TI Photoluminescence SO PHOTONICS SPECTRA LA English DT Letter C1 Natl Renewable Energy Lab, Spect Lab, Golden, CO USA. RP Dippo, P (reprint author), Natl Renewable Energy Lab, Spect Lab, Golden, CO USA. NR 0 TC 0 Z9 0 U1 1 U2 1 PU LAURIN PUBL CO INC PI PITTSFIELD PA BERKSHIRE COMMON PO BOX 1146, PITTSFIELD, MA 01202 USA SN 0731-1230 J9 PHOTON SPECTRA JI Photon. Spect. PD DEC PY 2001 VL 35 IS 12 BP 73 EP 73 PG 1 WC Optics SC Optics GA 499UW UT WOS:000172589600033 ER PT J AU Maslov, S AF Maslov, S TI Measures of globalization based on cross-correlations of world financial indices SO PHYSICA A LA English DT Article ID MATRICES; MARKETS AB The cross-correlation matrix of daily returns of stock market indices in a diverse set of 37 countries worldwide was analyzed. Comparison of the spectrum of this matrix with predictions of random matrix theory provides an empirical evidence of strong interactions between individual economies, as manifested by three largest eigenvalues and the corresponding set of stable, non-random eigenvectors. The observed correlation structure is robust with respect to changes in the time horizon of returns ranging from 1 to 10 trading days, and to replacing individual returns with just their signs. This last observation confirms that it is correlations between sips and not absolute values of fluctuations, which are mostly responsible for the observed effect. Negative changes in the index are somewhat more correlated than the positive ones. Also, in our data set the reaction of Asian stock indices to changes in European and American ones persists for about 3 days. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Maslov, S (reprint author), Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RI Maslov, Sergei/C-2397-2009 OI Maslov, Sergei/0000-0002-3701-492X NR 12 TC 24 Z9 24 U1 0 U2 4 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 1 PY 2001 VL 301 IS 1-4 BP 397 EP 406 DI 10.1016/S0378-4371(01)00370-3 PG 10 WC Physics, Multidisciplinary SC Physics GA 499WW UT WOS:000172594500031 ER PT J AU Berger, A Pechan, MJ Compton, R Jiang, JS Pearson, JE Bader, SD AF Berger, A Pechan, MJ Compton, R Jiang, JS Pearson, JE Bader, SD TI Disorder-tuning of hysteresis-loop properties in Co/CoO-film structures SO PHYSICA B LA English DT Article; Proceedings Paper CT 3rd International Symposium on Hysteresis and Micromagnetics Modeling CY MAY 21-23, 2001 CL UNIV GEORGE WASHINGTON, ASHBURN, VIRGINIA HO UNIV GEORGE WASHINGTON DE thin films; magnetic hysteresis; disorder tuning ID AVALANCHES; CRITICALITY; DIMENSIONS; DYNAMICS AB We have studied the effect of magnetic disorder on the magnetization reversal process in thin Co/CoO-films. The antiferromagnetic Coo layer allows a reversible tuning of the magnetic disorder by simple temperature variation, which was experimentally verified by measuring the ferromagnetic resonance linewidth as a function of temperature. The Co/CoO-films exhibit a discontinuous magnetization reversal process for temperatures above a critical temperature T-c, whereas smooth magnetization loops occur for T T-c. (C) 2001 Published by Elsevier Science B.V. C1 Argonne Natl Lab, Mat Sci Div, Argonne, IL 60439 USA. Miami Univ, Dept Phys, Oxford, OH 45056 USA. RP Berger, A (reprint author), IBM Corp, Almaden Res Ctr, 650 Harry Rd,K63-E3, San Jose, CA 95120 USA. RI Bader, Samuel/A-2995-2013; Berger, Andreas/D-3706-2015 OI Berger, Andreas/0000-0001-5865-6609 NR 15 TC 11 Z9 12 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD DEC PY 2001 VL 306 IS 1-4 BP 235 EP 239 DI 10.1016/S0921-4526(01)01010-9 PG 5 WC Physics, Condensed Matter SC Physics GA 501LC UT WOS:000172685300044 ER PT J AU Kato, J Itoh, KM Haller, EE AF Kato, J Itoh, KM Haller, EE TI Correlated to random transition of ionized impurity distribution in n-type Ge : (As, Ga) SO PHYSICA B-CONDENSED MATTER LA English DT Article; Proceedings Paper CT 21st International Conference on Defects in Semiconductors CY JUL 16-20, 2001 CL GIESSEN, GERMANY DE impurity distribution; compensated semiconductor; impurity absorption ID GERMANIUM; DONORS AB We discuss the broadening of ground-state to bounded excited-state transitions of shallow donors in strongly compensated n-type Ge: (As,Ga) in the presence of electric fields and their gradients, arising from randomly distributed ionized impurities. Quantitative comparison of the experimentally obtained linewidths with Monte Carlo simulation results makes possible, a unique determination of the ionized impurity distribution in the samples. We present clear evidence for the random-to-correlated transition of the ionized impurity distribution as a function of the ionized impurity concentration and of temperature. (C) 2001 Published by Elsevier Science B.V. C1 Keio Univ, Dept Appl Phys & Physicoinformat, Yokohama, Kanagawa 2238522, Japan. Univ Calif Berkeley, Berkeley, CA 94720 USA. Lawrence Berkeley Natl Labs, Berkeley, CA 94720 USA. RP Itoh, KM (reprint author), Keio Univ, Dept Appl Phys & Physicoinformat, 3-14-1 Hiyoshi, Yokohama, Kanagawa 2238522, Japan. RI Itoh, Kohei/C-5738-2014 NR 13 TC 0 Z9 0 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD DEC PY 2001 VL 308 BP 521 EP 524 DI 10.1016/S0921-4526(01)00751-7 PG 4 WC Physics, Condensed Matter SC Physics GA 518GV UT WOS:000173660100131 ER PT J AU Specht, P Cich, MJ Zhao, R Gebauer, J Luysberg, M Weber, ER AF Specht, P Cich, MJ Zhao, R Gebauer, J Luysberg, M Weber, ER TI Incorporation and thermal stability of defects in highly p-conductive non-stoichiometric GaAs : Be SO PHYSICA B-CONDENSED MATTER LA English DT Article; Proceedings Paper CT 21st International Conference on Defects in Semiconductors CY JUL 16-20, 2001 CL GIESSEN, GERMANY DE non-stoichiometric GaAs; Be doping; thermal stability; native point defects ID TEMPERATURE-GROWN GAAS; EPITAXIAL GAAS AB Non-stoichiometric GaAs is known to contain a high concentration of native point defects. The dominant defect in the epilayers is the arsenic antisite (As-Ga), a deep double donor, which is incorporated at low growth temperatures (commonly between 200degreesC and 300degreesC) in molecular beam epitaxy (MBE). Consequently, p-doping of non-stoichiometric GaAs is difficult because large concentrations of acceptors are compensated by the As-Ga. Recently, we found that despite this compensation effect we can achieve p-conductive GaAs: Be with almost one order of magnitude higher Be-doping than previously obtained in MBE grown GaAs. The kinetics of dopant incorporation during MBE growth at these low growth temperatures seem to allow pushing the doping concentration further beyond thermal equilibrium. The epilayers, which are about 1 mum thick, are pseudomorphic with a lattice mismatch to the substrate of up to Deltac/c = -0.4%. They remain free of structural defects such as dislocations and stacking faults. After annealing at 600degreesC only the highest doped epilayers show a reduction in the Be concentration although the layers remain ultrahigh p-conductive. The increased incorporation of Be as well as its unusual stability in non-stoichiometric GaAs is likely influenced by the native defects in these layers, double positively charged As-Ga defects and probably neutral gallium vacancies (V-Ga). This novel material which is solely achievable through low-temperature growth may significantly enhance III-V semiconductor applicability due to ultrahigh doping capability with increased thermal stability. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Calif Berkeley, Dept Mat Sci & Engn, LBNL, Berkeley, CA 94720 USA. Res Ctr Julich, Inst Solid State Res, D-52425 Julich, Germany. RP Specht, P (reprint author), Univ Calif Berkeley, Dept Mat Sci & Engn, LBNL, Bldg 66-222,1 Cyclotron Rd, Berkeley, CA 94720 USA. RI Luysberg, Martina/B-6448-2014 OI Luysberg, Martina/0000-0002-5613-7570 NR 16 TC 3 Z9 3 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD DEC PY 2001 VL 308 BP 808 EP 811 DI 10.1016/S0921-4526(01)00809-2 PG 4 WC Physics, Condensed Matter SC Physics GA 518GV UT WOS:000173660100203 ER PT J AU Gebauer, J Zhao, R Specht, P Borner, F Redmann, F Krause-Rehberg, R Weber, ER AF Gebauer, J Zhao, R Specht, P Borner, F Redmann, F Krause-Rehberg, R Weber, ER TI Native point defects in non-stoichiometric GaAs doped with beryllium SO PHYSICA B-CONDENSED MATTER LA English DT Article; Proceedings Paper CT 21st International Conference on Defects in Semiconductors CY JUL 16-20, 2001 CL GIESSEN, GERMANY DE LT-GaAs; Ga-vacancy; arsenic antisite; MCDA ID MOLECULAR-BEAM EPITAXY; TEMPERATURE-GROWN GAAS; ANTISITE AB Native point defects in non-stoichiometric GaAs layers doped with Be were observed. Ga vacancies were identified by positron annihilation. As-Ga antisite defects were investigated by near infrared absorption and magnetic circular dichroism of absorption, respectively. We found the properties of the As-Ga antisites very similar to that of As-Ga in bulk GaAs, i.e. they exhibit the same MCDA spectra and quenching behavior. The concentration of native point defects was not influenced by the Be doping. Therefore, the thermal stability of non-stoichiometric GaAs: Be can not be explained with a different incorporation of native defects. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Calif Berkeley, Dept Mat Sci & Engn, Berkeley, CA 94720 USA. Univ Halle Wittenberg, Fachbereich Phys, D-06099 Halle Saale, Germany. RP Gebauer, J (reprint author), Lawrence Berkeley Lab, Bldg 66,Rm 222,1 Cyclotron Rd, Berkeley, CA 94720 USA. NR 14 TC 0 Z9 0 U1 1 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD DEC PY 2001 VL 308 BP 812 EP 815 DI 10.1016/S0921-4526(01)00810-9 PG 4 WC Physics, Condensed Matter SC Physics GA 518GV UT WOS:000173660100204 ER PT J AU Bracht, H Norseng, MS Haller, EE Eberl, K AF Bracht, H Norseng, MS Haller, EE Eberl, K TI Zinc diffusion enhanced Ga diffusion in GaAs isotope heterostructures SO PHYSICA B-CONDENSED MATTER LA English DT Article; Proceedings Paper CT 21st International Conference on Defects in Semiconductors CY JUL 16-20, 2001 CL GIESSEN, GERMANY DE gallium arsenide isotope structure; gallium self-diffusion; zinc diffusion; zinc-induced interdiffusion ID GALLIUM-ARSENIDE; SELF-DIFFUSION AB We have investigated the simultaneous diffusion of Zn and Ga in a (69)GaAS/(71)GaAs isotope multilayer structure at temperatures between 618degreesC and 714degreesC. Diffusion profiles of Zn, (69)Ga, and (71)Ga were measured with secondary ion mass spectrometry. Accurate modeling of the simultaneous diffusion of Zn and Ga is achieved on the basis of a Ga vacancy and Ga interstitial controlled mode of Zn diffusion. This result is at variance with the generally accepted model of Zn diffusion via Ga self-interstitials. We discuss the consequences of our approach against the background of Zn and Cd diffusion experiments performed earlier. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Munster, Inst Materialphys, D-48149 Munster, Germany. Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. Univ Calif Berkeley, Berkeley, CA 94720 USA. Max Planck Inst Festkorperforschung, D-70569 Stuttgart, Germany. RP Bracht, H (reprint author), Univ Munster, Inst Materialphys, Wilhelm Klemm Str 10, D-48149 Munster, Germany. EM bracht@uni-muenster.de NR 12 TC 9 Z9 10 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD DEC PY 2001 VL 308 BP 831 EP 834 DI 10.1016/S0921-4526(01)00817-1 PG 4 WC Physics, Condensed Matter SC Physics GA 518GV UT WOS:000173660100209 ER PT J AU Zhang, SB Wei, SH AF Zhang, SB Wei, SH TI Nitrogen solubility and N-induced defect complexes in epitaxial GaAs : N SO PHYSICA B-CONDENSED MATTER LA English DT Article; Proceedings Paper CT 21st International Conference on Defects in Semiconductors CY JUL 16-20, 2001 CL GIESSEN, GERMANY DE impurity solubility; doping; impurity-defect complexes ID MOLECULAR-BEAM EPITAXY; GROWTH; ALLOYS AB Previous calculations suggested low-equilibrium N solubility in bulk GaAs. In epitaxial growth, however, N solubility can be significantly enhanced to as much as a few %. First-principles total-energy calculations show that this large difference is due to the lack of low-energy nucleation sites of GaN during epitaxy. As a result, the atomic chemical potential of N can be significantly larger. This gives rise to new defect physics distinctly different from those in GaAs. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Zhang, SB (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. RI Krausnick, Jennifer/D-6291-2013; Zhang, Shengbai/D-4885-2013 OI Zhang, Shengbai/0000-0003-0833-5860 NR 14 TC 5 Z9 5 U1 1 U2 7 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD DEC PY 2001 VL 308 BP 839 EP 842 DI 10.1016/S0921-4526(01)00890-0 PG 4 WC Physics, Condensed Matter SC Physics GA 518GV UT WOS:000173660100211 ER PT J AU Nicols, SP Bracht, H Benamara, M Liliental-Weber, Z Haller, EE AF Nicols, SP Bracht, H Benamara, M Liliental-Weber, Z Haller, EE TI Mechanism of zinc diffusion in gallium antimonide SO PHYSICA B-CONDENSED MATTER LA English DT Article; Proceedings Paper CT 21st International Conference on Defects in Semiconductors CY JUL 16-20, 2001 CL GIESSEN, GERMANY DE zinc diffusion; gallium antimonide; kick-out model; Ga self-interstitial ID GASB AB Zn diffusion experiments in GaSb at temperatures between 500degreesC and 650degreesC were performed using Ga-Zn alloy sources. For surface Zn concentrations exceeding 10(20)cm(-1), extended defects were detected using cross-sectional transmission electron microscopy (TEM). These defect networks correlate directly with the observed kink and tail profile shape. For lower Zn doping levels the kink disappears. The profiles of these samples reflect the diffusion behavior of Zn in virtually defect-free GaSb and are accurately described by a Ga interstitial controlled mode of Zn diffusion via the kick-out mechanism. Neutral and singly positively charged Ga interstitials mediate Zn diffusion at Zn doping levels of 1-2 x 10(19) and 3-10 x 10(19) cm(-3), respectively. The contribution of neutral Ga interstitials to Ga diffusion deduced from fitting experimental Zn profiles is in agreement with the directly measured Ga self-diffusion coefficient in GaSb isotope heterostructures. This provides strong evidence that Ga diffusion in undoped GaSb under Ga-rich conditions is mainly mediated by neutral Ga interstitials. Published by Elsevier Science B.V. C1 Univ Calif Berkeley, Berkeley, CA 94720 USA. Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. Univ Munster, Inst Materialphys, Munster, Germany. RP Nicols, SP (reprint author), Univ Calif Berkeley, 1 Cyclotron Rd MS 2-200, Berkeley, CA 94720 USA. RI Liliental-Weber, Zuzanna/H-8006-2012 NR 12 TC 17 Z9 18 U1 2 U2 7 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD DEC PY 2001 VL 308 BP 854 EP 857 DI 10.1016/S0921-4526(01)00913-9 PG 4 WC Physics, Condensed Matter SC Physics GA 518GV UT WOS:000173660100215 ER PT J AU Jasinski, J Yu, KM Walukiewicz, W Liliental-Weber, Z Washburn, J AF Jasinski, J Yu, KM Walukiewicz, W Liliental-Weber, Z Washburn, J TI Effects of structural defects on the activation of sulfur donors in GaNxAs1-x formed by N implantation SO PHYSICA B-CONDENSED MATTER LA English DT Article; Proceedings Paper CT 21st International Conference on Defects in Semiconductors CY JUL 16-20, 2001 CL GIESSEN, GERMANY DE GaNxAs1-x; TEM; microstructure; implantation ID BAND-GAP ENERGY; ION-IMPLANTATION; NITROGEN; GAAS; ALLOYS; GAN(X)AS1-X; INNXP1-X; GANAS AB The effects of structural defects on the electrical activity of S-doped GaNxAs1-x layers formed by S and N co-implantation in GaAs are reported. S and N ions were implanted to the depth of about 0.4mum. Electrochemical capacitance voltage measurements on samples annealed at 945degreesC for 10 s show that in a thin (< 0.1mum) surface layer the concentration of active shallow donors is almost an order of magnitude larger in S and N co-implanted samples than in samples implanted with S alone. The activation efficiency of S donors also shows a broad minimum at a depth of about 0.2 mum below the surface. The results of these electrical measurements are correlated with the distribution of structural defects revealed by transmission electron microscopy (TEM). The TEM micrographs show that in addition to a band of dislocation loops commonly found in ion implanted GaAs, an additional band of small voids is observed in samples co-implanted with S and N. The location of this band correlates well with the region of reduced electrical activation of S donors, suggesting that the formation of the voids through N accumulation results in a lower concentration of "active", substitutional N atoms. Published by Elsevier Science B.V. C1 Lawrence Berkeley Natl Lab, Mat Sci Div, Berkeley, CA 94720 USA. RP Lawrence Berkeley Natl Lab, Mat Sci Div, 1 Cyclotron Rd MS 62-203, Berkeley, CA 94720 USA. EM jbjasinski@lbl.gov RI Liliental-Weber, Zuzanna/H-8006-2012; Yu, Kin Man/J-1399-2012 OI Yu, Kin Man/0000-0003-1350-9642 NR 18 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 EI 1873-2135 J9 PHYSICA B JI Physica B PD DEC PY 2001 VL 308 BP 874 EP 876 DI 10.1016/S0921-4526(01)00930-9 PG 3 WC Physics, Condensed Matter SC Physics GA 518GV UT WOS:000173660100220 ER PT J AU Kisielowski, C Principe, E Freitag, B Hubert, D AF Kisielowski, C Principe, E Freitag, B Hubert, D TI Benefits of microscopy with super resolution SO PHYSICA B-CONDENSED MATTER LA English DT Article; Proceedings Paper CT 21st International Conference on Defects in Semiconductors CY JUL 16-20, 2001 CL GIESSEN, GERMANY DE transmission electron microscopy; gallium nitride; gate oxides; dislocations ID TRANSMISSION ELECTRON-MICROSCOPY; ATOMIC-SCALE; RECONSTRUCTION AB Transmission electron microscopy developed from an imaging tool into a quantitative electron beam characterization tool that locally accesses structure, chemistry and bonding in materials with sub-Angstrom resolution. Experiments utilize coherently and incoherently scattered electrons. In this contribution, the interface between gallium nitride and sapphire as well as thin silicon gate oxides are studied to understand underlying physical processes and the strength' of the different microscopy techniques. An investigation of the GaN/sapphire interface benefits largely from the application of phase contrast microscopy that makes it possible to visualize dislocation core structures and single columns of oxygen and nitrogen at a closest spacing of 85 pm. In contrast, it is adequate to investigate Si/SiOxNy/poly-Si interfaces with incoherently scattered electrons and electron spectroscopy because amorphous and poly-crystalline materials are involved. Here, it is demonstrated that the SiOxNy/poly-Si interface is rougher than the Si/SiOx interface, that desirable nitrogen diffusion gradients can be introduced into the gate oxide, and that a nitridation coupled with annealing increases its physical width while reducing the equivalent electrical oxide thickness to values approaching 1.2 nm. Therefore, an amorphous SiNxOy gate dielectric seems to be a suitable substitute for traditional gate oxides to further increase device speed by reducing dimensions in Si technology. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Ernest Orlando Lawrence Berkeley Natl Lab, Natl Ctr Electron Microscopy, Berkeley, CA 94720 USA. Appl Mat Inc, Santa Clara, CA 95054 USA. FEI Co, NL-5600 MD Eindhoven, Netherlands. RP Kisielowski, C (reprint author), Ernest Orlando Lawrence Berkeley Natl Lab, Natl Ctr Electron Microscopy, Berkeley, CA 94720 USA. NR 23 TC 21 Z9 21 U1 1 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 J9 PHYSICA B JI Physica B PD DEC PY 2001 VL 308 BP 1090 EP 1096 DI 10.1016/S0921-4526(01)00896-1 PG 7 WC Physics, Condensed Matter SC Physics GA 518GV UT WOS:000173660100274 ER PT J AU Lorenz, B Meng, RL Cmaidalka, J Wang, YS Lenzi, J Xue, YY Chu, CW AF Lorenz, B Meng, RL Cmaidalka, J Wang, YS Lenzi, J Xue, YY Chu, CW TI Synthesis, characterization and physical properties of the superconducting ferromagnet RuSr2GdCu2O8 SO PHYSICA C LA English DT Article DE synthesis of RuSr2GdCu2O8; structure; magnetic susceptibility; electrical resistivity; thermoelectric power ID GD; COEXISTENCE; EU AB Superconducting ferromagnet RuSr2GdCu2O8 has been synthesized and characterized structurally and electrically by X-ray diffraction, resistivity and thermoelectric power measurements. Special attention was paid to investigating the influence of synthesis parameters on the superconducting properties. From thermoelectric power data it can be concluded that the carrier density is not affected by changing the conditions of synthesis. However, carefully tuning the details of sample preparation may significantly change the intra-gain and inter-gain transition temperatures. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Houston, Dept Phys, Texas Ctr Superconduct, Houston, TX 77204 USA. Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Lorenz, B (reprint author), Univ Houston, Dept Phys, Texas Ctr Superconduct, Houston, TX 77204 USA. EM blorenz@bayou.uh.edu NR 17 TC 27 Z9 28 U1 0 U2 3 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 1 PY 2001 VL 363 IS 4 BP 251 EP 259 DI 10.1016/S0921-4534(01)00830-9 PG 9 WC Physics, Applied SC Physics GA 492TG UT WOS:000172183200007 ER PT J AU Lapenta, G AF Lapenta, G TI Ion flow induced attractive force in complex plasma crystals SO PHYSICA SCRIPTA LA English DT Article ID DUST PARTICLES; ANISOTROPIC PLASMAS; SIMULATION; DISCHARGE; DYNAMICS; SHEATH; GRAIN; PARTICULATE; POTENTIALS; DRAG AB In the present paper, I consider the problem of what is the nature of the attractive force observed experimentally in complex plasma crystals. Currently, the most accepted theory predicts that an electrostatic force caused by a wake field is responsible for the attraction. I propose that, in the typical conditions found in the majority of experiments, the wake produces another effect: the distortion of the ion trajectories causes an attractive force via direct momentum transfer (i.e. ion drag force). A dust particle located at the edge of a sheath is immersed in flowing ions. The dust particle is generally negatively charged and causes a focusing of the ion trajectories. If a second particle is located downstream, the effect of the converging ion orbits is to align the second dust particle downstream of the first. This ion flow induced attractive force has two properties that makes it a viable candidate. First, the force is one sided: particles downstream are affected by particles upstream but not vice-versa (exactly as observed in experiments). Second, the new force proposed here is of the same order as the electrostatic wake force and much larger than other forces previously considered (dipole forces). C1 Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Politecn Torino, Sez Torino, INFM, I-10129 Turin, Italy. RP Lapenta, G (reprint author), Los Alamos Natl Lab, Div Theoret, Mail Stop K717, Los Alamos, NM 87545 USA. EM lapenta@lanl.gov OI Lapenta, Giovanni/0000-0002-3123-4024 NR 28 TC 14 Z9 14 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0031-8949 J9 PHYS SCRIPTA JI Phys. Scr. PD DEC PY 2001 VL 64 IS 6 BP 599 EP 604 DI 10.1238/Physica.Regular.064a00599 PG 6 WC Physics, Multidisciplinary SC Physics GA 509HC UT WOS:000173140100013 ER PT J AU Chantler, CT Tran, CQ Barnea, Z Paterson, D Cookson, DJ Balaic, DX AF Chantler, CT Tran, CQ Barnea, Z Paterson, D Cookson, DJ Balaic, DX TI Measurement of the x-ray mass attenuation coefficient of copper using 8.85-20 keV synchrotron radiation SO PHYSICAL REVIEW A LA English DT Article ID ABSORPTION FINE-STRUCTURE; MATCHED ION CHAMBERS; ATOMIC FORM-FACTORS; CROSS-SECTIONS; MONITORING FLUCTUATIONS; POWDER DIFFRACTOMETER; INTERNATIONAL-UNION; DIFFERENCE METHOD; IMAGING PLATES; SCATTERING AB This work presents the x-ray extended range technique for measuring x-ray mass attenuation coefficients. This technique includes the use of multiple foil attenuators at each energy investigated, allowing independent tests of detector linearity and of the harmonic contributions to the monochromated synchrotron beam. Measurements over a wide energy range allow the uncertainty of local foil thickness to be minimized by the calibration of thin sample measurements to those of thick samples. The use of an extended criterion for sample thickness selection allows direct determination of dominant systematics, with an improvement of accuracies compared to previous measurements by up to factors of 20. Resulting accuracies for attenuation coefficients of copper (8.84 to 20 keV) are 0.27-0.5%, with reproducibility of 0.02%. We also extract the imaginary component of the form factor from the data with the same accuracy. Results are compared to theoretical calculations near and away from the absorption edge. The accuracy challenges available theoretical calculations, and observed discrepanicies of 10% between current theory and experiments can now be addressed. C1 Univ Melbourne, Sch Phys, Parkville, Vic 3010, Australia. Australian Nucl Sci & Technol Org, Menai, NSW 2234, Australia. Argonne Natl Lab, Chem Mat CARS CAT, Argonne, IL 60439 USA. RP Univ Melbourne, Sch Phys, Parkville, Vic 3010, Australia. RI Tran, Chanh/M-7868-2015; Chantler, Christopher/D-4744-2013 OI Chantler, Christopher/0000-0001-6608-0048 NR 58 TC 65 Z9 67 U1 1 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9926 EI 2469-9934 J9 PHYS REV A JI Phys. Rev. A PD DEC PY 2001 VL 64 IS 6 AR 062506 DI 10.1103/PhysRevA.64.062506 PG 15 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 500CK UT WOS:000172608200036 ER PT J AU Grice, WP U'Ren, AB Walmsley, IA AF Grice, WP U'Ren, AB Walmsley, IA TI Eliminating frequency and space-time correlations in multiphoton states SO PHYSICAL REVIEW A LA English DT Article ID EXPERIMENTAL QUANTUM TELEPORTATION; HORNE-ZEILINGER ENTANGLEMENT; DOWN-CONVERSION; PUMP AB Multiphoton states constructed from photon pairs generated in the process of spontaneous parametric down-conversion possess frequency and space-time correlations that may carry undesired distinguishing information. It is shown that these correlations may be eliminated if certain conditions in the source configuration are satisfied. For the cases in which these conditions cannot be satisfied because of experimental constraints, it is shown that the correlations may be reduced through proper choices of crystal length and pump bandwidth. The advantage of such source engineering is that it yields much higher count rates, since no photon pairs are lost by predetection spectral filtering. C1 Oak Ridge Natl Lab, Div Math & Comp Sci, Ctr Engn Sci Adv Res, Oak Ridge, TN 37831 USA. Univ Rochester, Inst Opt, Rochester, NY 14627 USA. RP Grice, WP (reprint author), Oak Ridge Natl Lab, Div Math & Comp Sci, Ctr Engn Sci Adv Res, Oak Ridge, TN 37831 USA. RI Grice, Warren/L-8466-2013 NR 14 TC 219 Z9 220 U1 4 U2 12 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD DEC PY 2001 VL 64 IS 6 AR 063815 DI 10.1103/PhysRevA.64.063815 PG 7 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 500CK UT WOS:000172608200099 ER PT J AU Vanroose, W AF Vanroose, W TI Double pole of the S matrix in a double-well system SO PHYSICAL REVIEW A LA English DT Article ID ELECTRON-ATOM SCATTERING AB We discuss the interaction between two resonant states in a quantum double-well structure. The behavior of the resonant states depends on the coupling between the wells, i.e.. the height and width of the barrier that separates them. We distinguish a region with resonant tunneling and a region where the two resonances repel each other. The transition between the two regions is marked by a double pole of the S matrix. C1 Univ Antwerp, Dept Wiskunde Informat, B-2020 Antwerp, Belgium. RP Vanroose, W (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. EM wivanroose@lbl.gov RI Vanroose, Wim/J-4292-2013 OI Vanroose, Wim/0000-0001-8349-1391 NR 11 TC 26 Z9 26 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD DEC PY 2001 VL 64 IS 6 AR 062708 DI 10.1103/PhysRevA.64.062708 PG 3 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 500CK UT WOS:000172608200045 ER PT J AU Bianchi, A Movshovich, R Jaime, M Thompson, JD Pagliuso, PG Sarrao, JL AF Bianchi, A Movshovich, R Jaime, M Thompson, JD Pagliuso, PG Sarrao, JL TI Origin of the zero-resistance anomaly in heavy fermion superconducting CeIrIn5: A clue from magnetic-field and Rh-doping studies SO PHYSICAL REVIEW B LA English DT Article AB We present the results of the specific heat and ac magnetic susceptibility measurements of CeIr1-xRhxIn5 for x from 0 to 0.5. As x is increased from zero both quantities reflect the competition between two effects. The first is a suppression of superconductivity below the bulk transition temperature of T-c = 0.4 K, which is due to the pair breaking, effect of Rh impurities. The second is an increase in the volume fraction of the superconducting regions above T-c, which we attribute to defect-induced strain. Analysis of the H-T phase diagram for CeIrIn5 obtained from the bulk probes and resistance measurements points to the filamentary origin of the inhomogeneous superconductivity at T(rho)approximate to1.2 K, where the resistance drops to zero. The identical anisotropies in the magnetic field dependence of the specific heat and the resistance anomalies in CeIrln(5) indicate that the filamentary superconductivity is intrinsic, involving electrons from the part of the Fermi surface responsible for bulk superconductivity. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. RI Pagliuso, Pascoal/C-9169-2012; Jaime, Marcelo/F-3791-2015; Bianchi, Andrea/E-9779-2010 OI Jaime, Marcelo/0000-0001-5360-5220; Bianchi, Andrea/0000-0001-9340-6971 NR 16 TC 33 Z9 33 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 1 PY 2001 VL 64 IS 22 AR 220504 DI 10.1103/PhysRevB.64.220504 PG 4 WC Physics, Condensed Matter SC Physics GA 502FP UT WOS:000172733300010 ER PT J AU Dai, PC Fernandez-Baca, JA Plummer, EW Tomioka, Y Tokura, Y AF Dai, PC Fernandez-Baca, JA Plummer, EW Tomioka, Y Tokura, Y TI Magnetic coupling in the insulating and metallic ferromagnetic La1-xCaxMnO3 SO PHYSICAL REVIEW B LA English DT Article ID DOUBLE-EXCHANGE MODEL; DOPED MANGANITES; SPIN-DIFFUSION; LA1-XSRXMNO3; TRANSITION; POLARON; EXCITATION; CROSSOVER; DYNAMICS; WAVES AB Low-energy spin excitations play an essential role in determining the characteristics of the phase transitions in the colossal magnetoresistant manganese-oxides (manganites). Inelastic neutron scattering has been utilized to study the spin excitations of the ferromagnetic (FM) La1-xCaxMnO3 (LCMO) as a function of hole doping x (0.2, 0.25, and 0.30) and temperature, above and below the Curie temperature Tc. While the spin-diffusion coefficients Lambda (T) and T-c's increase smoothly with doping concentration x, the spin-stiffness constant D(T) for the insulating LCMO is 3 times smaller than that of the metallic LCMO. Furthermore, the paramagnetic-to-ferromagnetic phase transitions in LCMO manganites investigated have nonvanishing extrapolated values of D(T) as T --> T-c and nondiverging spin-correlation lengths at Tc. These results present a serious challenge to the understanding of these materials using models such as Heisenberg ferromagnetism, double exchange, or modified double exchange. C1 Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. JRCAT, Tsukuba, Ibaraki 3050046, Japan. AIST, CERC, Tsukuba, Ibaraki 3058562, Japan. Univ Tokyo, Dept Appl Phys, Tokyo 1138656, Japan. RP Dai, PC (reprint author), Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. RI Dai, Pengcheng /C-9171-2012; Tokura, Yoshinori/C-7352-2009; Fernandez-Baca, Jaime/C-3984-2014 OI Dai, Pengcheng /0000-0002-6088-3170; Fernandez-Baca, Jaime/0000-0001-9080-5096 NR 39 TC 34 Z9 35 U1 0 U2 11 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 1 PY 2001 VL 64 IS 22 AR 224429 DI 10.1103/PhysRevB.64.224429 PG 6 WC Physics, Condensed Matter SC Physics GA 502FP UT WOS:000172733300072 ER PT J AU Dolinsek, J Jaglicic, Z Chernikov, MA Fisher, IR Canfield, PC AF Dolinsek, J Jaglicic, Z Chernikov, MA Fisher, IR Canfield, PC TI Unusual spin-glass phase in icosahedral Tb-Mg-Zn quasicrystals SO PHYSICAL REVIEW B LA English DT Article ID R = Y; QUASI-CRYSTALS; SINGLE-GRAIN; ISING-MODEL; HO; DY; ER; CHAIN AB The nature of the spin state below the spin freezing temperature was studied in an icosahedral Th-Mg-Zn quasicrystal by thermoremanent dc magnetization time decay as a function of aging time and magnetic field. The system does not exhibit a highly degenerate free-energy landscape obeying an ultrametric organization of metastable states, which makes it essentially different from canonical spin glasses. The Th-Mg-Zn system can be considered as a special class of spin glass, which possesses some local order, but still preserves the notion of spin freezing. C1 Univ Ljubljana, Jozef Stefan Inst, SI-1000 Ljubljana, Slovenia. Inst Math Phys & Mech, SI-1000 Ljubljana, Slovenia. Univ Houston, Texas Ctr Superconduct, Houston, TX 77204 USA. Stanford Univ, Adv Mat Lab, Stanford, CA 94305 USA. Stanford Univ, Dept Appl Phys, Stanford, CA 94305 USA. Iowa State Univ, Ames Lab, Ames, IA USA. Iowa State Univ, Dept Phys & Astron, Ames, IA USA. RP Dolinsek, J (reprint author), Univ Ljubljana, Jozef Stefan Inst, Jamova 39, SI-1000 Ljubljana, Slovenia. RI Canfield, Paul/H-2698-2014 NR 18 TC 18 Z9 18 U1 1 U2 4 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 1 PY 2001 VL 64 IS 22 AR 224209 DI 10.1103/PhysRevB.64.224209 PG 4 WC Physics, Condensed Matter SC Physics GA 502FP UT WOS:000172733300038 ER PT J AU Hall, D Palm, EC Murphy, TP Tozer, SW Fisk, Z Alver, U Goodrich, RG Sarrao, JL Pagliuso, PG Ebihara, T AF Hall, D Palm, EC Murphy, TP Tozer, SW Fisk, Z Alver, U Goodrich, RG Sarrao, JL Pagliuso, PG Ebihara, T TI Fermi surface of the heavy-fermion superconductor CeCoIn5: The de Haas-van Alphen effect in the normal state SO PHYSICAL REVIEW B LA English DT Article ID CERHIN5 AB Measurements of the de Haas-van Alphen effect in the normal state of the heavy-fermion superconductor CeCoIn5 have been carried out using a torque cantilever at temperatures ranging from 20 to 500 mK and in fields up to 18 T. Angular-dependent measurements of the extremal Fermi surface areas reveal a more extreme two-dimensional sheet than is found in either CeRhIn5 or CeIrIn5. The effective masses of the measured frequencies range from 9 to 20m*/m(0). C1 Florida State Univ, Natl High Magnet Field Lab, Tallahassee, FL 32310 USA. Louisiana State Univ, Dept Phys & Astron, Baton Rouge, LA 70802 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Shizuoka Univ, Fac Sci, Dept Phys, Shizuoka 4228529, Japan. RP Florida State Univ, Natl High Magnet Field Lab, Tallahassee, FL 32310 USA. RI Pagliuso, Pascoal/C-9169-2012; OI Hall, Donavan/0000-0001-5036-5188 NR 10 TC 90 Z9 90 U1 1 U2 9 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 1 PY 2001 VL 64 IS 21 AR 212508 DI 10.1103/PhysRevLett.87.212508 PG 3 WC Physics, Condensed Matter SC Physics GA 499EH UT WOS:000172557700022 ER PT J AU Jin, R Paranthaman, M Zhai, HY Christen, HM Christen, DK Mandrus, D AF Jin, R Paranthaman, M Zhai, HY Christen, HM Christen, DK Mandrus, D TI Unusual Hall effect in superconducting MgB2 films SO PHYSICAL REVIEW B LA English DT Article ID SIGN REVERSAL; II SUPERCONDUCTORS; VORTICES PARALLEL; CUO2 LAYERS; YBA2CU3O7-DELTA; ORIGIN AB We have investigated the temperature and magnetic field dependence of the Hall coefficient of two well-characterized superconducting MgB2 films (T-c0 = 38.0 K) in both the normal and superconducting states. Our results show that the normal-state Hall coefficient R-H is positive and increases with decreasing temperature, independent of the applied magnetic field (to 8 T). We find that R(H)(-1)proportional to T(40-300 K) and cot OH proportional toT(2)(100-300 K). As the sample is cooled below T-c(H), R-H decreases rapidly with temperature and changes sign before it reaches zero. The position and magnitude at which R-H shows a minimum depends on the applied field. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. EM jinr@ornl.gov RI Christen, David/A-9709-2008; Christen, Hans/H-6551-2013; Mandrus, David/H-3090-2014; Paranthaman, Mariappan/N-3866-2015 OI Christen, Hans/0000-0001-8187-7469; Paranthaman, Mariappan/0000-0003-3009-8531 NR 33 TC 41 Z9 45 U1 0 U2 4 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 1 PY 2001 VL 64 IS 22 AR 220506 DI 10.1103/PhysRevB.64.220506 PG 4 WC Physics, Condensed Matter SC Physics GA 502FP UT WOS:000172733300012 ER PT J AU Karen, P Woodward, PM Linden, J Vogt, T Studer, A Fischer, P AF Karen, P Woodward, PM Linden, J Vogt, T Studer, A Fischer, P TI Verwey transition in mixed-valence TbBaFe2O5: Two attempts to order charges SO PHYSICAL REVIEW B LA English DT Article ID OXYGEN-DEFICIENT PEROVSKITE; RARE-EARTH MANGANATES; MAGNETIC-STRUCTURE; POWDER DIFFRACTION; PHASE-TRANSITIONS; RNIO3 PEROVSKITES; DISPROPORTIONATION; TEMPERATURE; CRYSTAL; FLUCTUATIONS AB Electronic, magnetic. and structural phase transitions in nearly stoichiometric TbBaFe2O5+w (0.00 direction than in the < 001 > direction. The quantitative analysis provides an estimate of the correlation length xi, or size of the regions, and shows that xi (< 111 >) similar to1.24 xi (< 001 >), consistent with the primary or dominant displacement of Pb leading to the low-temperature rhombohedral phase. Both the appearance of the polar regions at T* and the structural transition at T-c are marked by kinks in the xi (< 111 >), curve but not in the xi (< 001 >) one, also indicating that the primary changes take place in a < 111 > direction at both temperatures. C1 Lehigh Univ, Dept Phys, Bethlehem, PA 18015 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Simon Fraser Univ, Dept Chem, Burnaby, BC V5A 1S6, Canada. RP La-Orauttapong, D (reprint author), Lehigh Univ, Dept Phys, Bldg 16, Bethlehem, PA 18015 USA. NR 21 TC 52 Z9 52 U1 3 U2 7 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 1 PY 2001 VL 64 IS 21 AR 212101 DI 10.1103/PhysRevLett.87.212101 PG 4 WC Physics, Condensed Matter SC Physics GA 499EH UT WOS:000172557700001 ER PT J AU Pierce, JP Torija, MA Shen, J Plummer, EW AF Pierce, JP Torija, MA Shen, J Plummer, EW TI Mapping the magnetic phase diagram of metastable fct Fe/Cu(100) using Co atoms SO PHYSICAL REVIEW B LA English DT Article ID ULTRATHIN FERROMAGNETIC-FILMS; REORIENTATION TRANSITIONS; FE FILMS; STRUCTURAL TRANSFORMATION; SPIN REORIENTATION; THICKNESS-DRIVEN; TEMPERATURE; ANISOTROPY; CU(100); DEPENDENCE AB In ultrathin Fe films grown at room temperature on Cu(100), observed thickness and temperature-dependent spin reorientations are preceded by structural trans formations. We use a method involving Co capping atoms to generate a magnetic phase diagram for this system in the absence of these structural changes. Th phase diaaram shows that the recently observed stripe-phase melting in the Fe/Cu(100) system is related to the onset of a spin reorientation, rather than to a ferromagnetic-to-paramagnetic transition. In addition, the phase diagram allows us to determine the temperature-dependent anisotropy constants for Fe/Cu(100) films. C1 Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Univ Tennessee, Dept Phys, Knoxville, TN 37996 USA. RP Shen, J (reprint author), Oak Ridge Natl Lab, Div Solid State, POB 2008, Oak Ridge, TN 37831 USA. NR 19 TC 14 Z9 14 U1 0 U2 4 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 1 PY 2001 VL 64 IS 22 AR 224409 DI 10.1103/PhysRevB.64.224409 PG 4 WC Physics, Condensed Matter SC Physics GA 502FP UT WOS:000172733300052 ER PT J AU Regan, TJ Ohldag, H Stamm, C Nolting, F Luning, J Stohr, J White, RL AF Regan, TJ Ohldag, H Stamm, C Nolting, F Luning, J Stohr, J White, RL TI Chemical effects at metal/oxide interfaces studied by x-ray-absorption spectroscopy SO PHYSICAL REVIEW B LA English DT Article ID MAGNETIC CIRCULAR-DICHROISM; MOLECULAR-BEAM EPITAXY; THIN-FILMS; ELECTRON-YIELD; SUM-RULES; NIO; IRON; FE; PHOTOABSORPTION; TEMPERATURE AB A chemical and magnetic characterization of ferromagnet/antiferromagnet interfaces is essential to understand the microscopic origins of exchange anisotropy and other magnetic phenomena. We have used high-resolution L-edge x-ray absorption spectroscopy (XAS), which is element specific and sensitive to chemical environment and spin orientation, to investigate the interface of antiferromagnetic oxides with ferromagnetic metals. Clear quantitative evidence of oxidation/reduction reactions at the as-grown metal/oxide interface is presented. In situ- and ex situ-grown samples of the form oxide (5-30 Angstrom)/metal(1-10 Angstrom),where oxide is either NiO or CoO and metal is either Fe, Co, or Ni, were studied by high-resolution XAS. For all samples, a metal(oxide) layer adjacent to an oxide(metal) layer was partially oxidized(reduced). Quantitative analysis of the spectra showed that one to two atomic layers on either side of the inter-face were oxidized/reduced. An elemental series of samples showed that the amount of oxidation/reduction was in accord with the difference in oxidation potentials of the adjacent cations, e.g., oxide layers were more strongly reduced by an iron metal layer than by cobalt or nickel metal layers. Annealing to temperatures, typically used to bias devices, was shown to significantly increase the amount of oxidation/reduction. The oxidation behavior of iron was shown to depend on the amount of oxygen available. Our results are believed to provide important information for the improved understanding of exchange anisotropy. C1 Stanford Univ, Dept Appl Phys, Stanford, CA 94305 USA. Stanford Synchrotron Radiat Lab, Stanford, CA 94309 USA. RP Regan, TJ (reprint author), Stanford Univ, Dept Appl Phys, Stanford, CA 94305 USA. EM tom.regan@kla-tencor.com RI Stamm, Christian/G-4814-2013; Ohldag, Hendrik/F-1009-2014 OI Stamm, Christian/0000-0001-5611-9084; NR 30 TC 334 Z9 335 U1 17 U2 143 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 1 PY 2001 VL 64 IS 21 AR 214422 DI 10.1103/PhysRevLett.87.214422 PG 11 WC Physics, Condensed Matter SC Physics GA 499EH UT WOS:000172557700064 ER PT J AU Roundy, D Cohen, ML AF Roundy, D Cohen, ML TI Ideal strength of diamond, Si, and Ge SO PHYSICAL REVIEW B LA English DT Article ID ULTRA-MICRO-INDENTATION; PHASE-TRANSFORMATION; SPHERICAL INDENTERS; TOTAL ENERGY; SILICON; STRESS AB We have calculated the ideal shear strength and ideal tensile strength of C, Si, and Ge in the diamond structure. We find ideal shear strengths of 95 GPa, 6.5 GPa. and 4.5 GPa, and ideal tensile strengths of 95 GPa. 23 GPa, and 14 GPa for C, Si and Ge respectively. The shear calculation is performed on the {111} slip plane sheared in a < 112 > direction, and the tensile load is applied in the < 111 > direction. We allowed for a full relaxation of the strains orthogonal to the applied strain as well as the atomic basis vectors. C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. NR 19 TC 140 Z9 144 U1 5 U2 29 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 1 PY 2001 VL 64 IS 21 AR 212103 DI 10.1103/PhysRevB.64.212103 PG 3 WC Physics, Condensed Matter SC Physics GA 499EH UT WOS:000172557700003 ER PT J AU Ruhlander, M Markos, P Soukoulis, CM AF Ruhlander, M Markos, P Soukoulis, CM TI Symmetry, dimension, and the distribution of the conductance at the mobility edge SO PHYSICAL REVIEW B LA English DT Article ID METAL-INSULATOR-TRANSITION; ANDERSON TRANSITION; DISORDERED-SYSTEMS; PROBABILITY-DISTRIBUTION; SCALING PROPERTIES; 2 DIMENSIONS; LOCALIZATION; UNIVERSALITY AB The probability distribution of the conductance at the mobility edge, p(c)(g), in different universality classes and dimensions is investigated numerically for a variety of random systems. It is shown that p(c)(g) is universal for systems of given symmetry, dimensionality, and boundary conditions. An analytical form of p(c)(g) for small values of g is discussed and agreement with numerical data is observed. For g>1. In p(c)(g) is proportional to (g-1) rather than (g-1)(2). C1 Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. Slovak Acad Sci, Inst Phys, Bratislava 84228, Slovakia. RP Iowa State Univ, Ames Lab, Ames, IA 50011 USA. RI Soukoulis, Costas/A-5295-2008 NR 25 TC 29 Z9 29 U1 0 U2 2 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 1 PY 2001 VL 64 IS 21 AR 212202 DI 10.1103/PhysRevLett.87.212202 PG 4 WC Physics, Condensed Matter SC Physics GA 499EH UT WOS:000172557700006 ER PT J AU Schmidt, HJ Schnack, J Luban, M AF Schmidt, HJ Schnack, J Luban, M TI Heisenberg exchange parameters of molecular magnets from the high-temperature susceptibility expansion SO PHYSICAL REVIEW B LA English DT Article ID CLUSTERS; COMPLEX AB We provide exact analytical expressions for the magnetic susceptibility function in the high-temperature expansion for finite Heisenberg spin systems with an arbitrary coupling matrix, arbitrary single-spin quantum number, and arbitrary number of spins. The results can be used to determine unknown exchange parameters from zero-field magnetic susceptibility measurements without diagonalizing the system Hamiltonian. We demonstrate the possibility of reconstructing the exchange parameters from simulated data for two specific model systems. We examine the accuracy and stability of the proposed method. C1 Univ Osnabruck, Fachbereich Phys, D-49069 Osnabruck, Germany. Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. RP Schmidt, HJ (reprint author), Univ Osnabruck, Fachbereich Phys, Barbarastr 7, D-49069 Osnabruck, Germany. EM jschnack@uos.de RI Schnack, Jurgen/A-4079-2008 OI Schnack, Jurgen/0000-0003-0702-2723 NR 21 TC 17 Z9 17 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 1 PY 2001 VL 64 IS 22 AR 224415 DI 10.1103/PhysRevB.64.224415 PG 6 WC Physics, Condensed Matter SC Physics GA 502FP UT WOS:000172733300058 ER PT J AU Smakov, J Martin, I Balatsky, AV AF Smakov, J Martin, I Balatsky, AV TI Josephson scanning tunneling microscopy SO PHYSICAL REVIEW B LA English DT Article ID T-C SUPERCONDUCTORS; QUASI-PARTICLES; BI2SR2CACU2O8+DELTA; SYMMETRY; ORDER; JUNCTIONS; PB AB We propose a set of scanning tunneling microscopy experiments in which the surface of a superconductor is scanned by a superconducting tip. Potential capabilities of such experimental setup are discussed. Most important anticipated results of such an experiment include the position-resolved measurement of the superconducting order parameter and the possibility to determine the nature of the secondary component of the order parameter at the surface. The theoretical description based on the tunneling Hamiltonian formalism is presented. C1 Royal Inst Technol, Dept Phys, SCFAB, SE-10691 Stockholm, Sweden. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Royal Inst Technol, Dept Phys, SCFAB, SE-10691 Stockholm, Sweden. NR 21 TC 21 Z9 21 U1 0 U2 5 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 1 PY 2001 VL 64 IS 21 AR 212506 DI 10.1103/PhysRevB.64.212506 PG 4 WC Physics, Condensed Matter SC Physics GA 499EH UT WOS:000172557700020 ER PT J AU Song, C Johnson, D Wermeille, D Goldman, AI Bud'ko, SL Fisher, IR Canfield, PC AF Song, C Johnson, D Wermeille, D Goldman, AI Bud'ko, SL Fisher, IR Canfield, PC TI Observation of a spin reorientation in TbCu2Ge2 from resonant and nonresonant x-ray scattering SO PHYSICAL REVIEW B LA English DT Article ID EXCHANGE-SCATTERING; MAGNETIC-STRUCTURES; POLARIZATION DEPENDENCE; NEUTRON-DIFFRACTION; TRANSITION; ERNI2B2C; RNI2GE2 AB Resonant and nonresonant magnetic x-ray scattering measurements have been carried out on a single crystal of ThCu2Ge2. dc susceptibility measurements on single crystals clearly showed two transitions at T-N = 12.3 K and T-r = 9.6 K. The temperature dependence of both the resonant and nonresonant magnetic scattering were fit self-consistently and revealed a reorientation of the moments in the basal plane from [110] below T-t, to [010] for temperatures T-tO, consistent with annihilation within the target nucleus. The relationship between N-g and the number of scatterings of the proton in the nucleus is used to estimate the (p) over bar annihilation cross section in the nuclear medium, The resulting cross section is at least a factor of 5 smaller than the free (p) over bar -p annihilation cross section when assuming a small or negligible formation time. Only with a long formation time can the data be described with the free (p) over bar -p annihilation cross section. C1 Columbia Univ, New York, NY 10027 USA. Nevis Labs, Irvington, NY 10523 USA. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. Florida State Univ, Tallahassee, FL 32306 USA. SUNY Stony Brook, Stony Brook, NY 11794 USA. Kent State Univ, Kent, OH 44242 USA. Yonsei Univ, IPAP, Seoul 120749, South Korea. Univ Tennessee, Knoxville, TN 37996 USA. Ernest O Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. Iowa State Univ, Ames, IA 50010 USA. IIT, Chicago, IL 60616 USA. RP Chemakin, I (reprint author), Columbia Univ, New York, NY 10027 USA. OI Torun, Yagmur/0000-0003-2336-6585; Hartouni, Edward/0000-0001-9869-4351 NR 20 TC 7 Z9 7 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD DEC PY 2001 VL 64 IS 6 AR 064908 DI 10.1103/PhysRevC.64.064908 PG 6 WC Physics, Nuclear SC Physics GA 502FL UT WOS:000172733000053 ER PT J AU Garrow, KR Adimi, F Kolb, NR Lu, J Pywell, RE Skopik, DM Vogt, JM Jury, JW Kuzin, A Thompson, MN Ryckebusch, J AF Garrow, KR Adimi, F Kolb, NR Lu, J Pywell, RE Skopik, DM Vogt, JM Jury, JW Kuzin, A Thompson, MN Ryckebusch, J TI High resolution measurement of the O-16(gamma,pn)N-14(0,1,2,...) reaction SO PHYSICAL REVIEW C LA English DT Article ID 2-NUCLEON PHOTOEMISSION; SCINTILLATORS; ABSORPTION; PHOTONS; NUCLEI; O-16 AB The exclusive O-16(gamma ,pn) N-14(0,1,2...) reaction was measured for the photon energy range E-gamma=98.5 to 141.0 MeV with an excitation energy resolution of 2.8 MeV. Protons were detected at 76 degrees and 82 degrees and coincident neutrons were detected at the opening angle for quasifree deuteron photodisintegration. Only the T=0, 1(+), 3.95 MeV state in the residual N-14 nucleus was significantly populated. This corresponds to a preferred L=0 angular momentum transfer to the recoil nucleus as is expected for quasifree kinematics. The absence of significant population to other discrete states is evidence that absorption on correlated proton-neutron pairs with an angular momentum transfer of L greater than or equal to2 is largely suppressed for the low recoil momentum range of the current measurement. As a consequence of this fact, and the absence of unnatural parity states, only absorption on proton-neutron pairs in relative motion l=0,2 is expected for all possible shell model couplings. No significant population of the T=1 state at 2.31 MeV is consistent with previous measurements, demonstrating that absorption on proton-neutron pairs in an isospin triplet is suppressed. The results of the measurement to discrete states in the residual N-14 nucleus are compared to microscopic calculations which include contributions above that of the mean field due to the short range and tensor parts of the nuclear potential. Clear separation in the contribution of (1p)(-2) and (1p)(-1)(1s)(-1) proton-neutron pairs is seen to occur at an excitation energy of 20+/-2 MeV. Significant population of the (1p)(-1)(1s)(-1) continuum above 20 MeV indicates that absorption on L=1 nucleon pairs is also important near quasifree kinematics. C1 Univ Saskatchewan, Saskatchewan Accelerator Lab, Saskatoon, SK S7N 5C6, Canada. Trent Univ, Dept Phys, Peterborough, ON K9J 7B8, Canada. Univ Melbourne, Sch Phys, Parkville, Vic 3052, Australia. State Univ Ghent, Dept Subatom & Radiat Phys, B-9000 Ghent, Belgium. RP Garrow, KR (reprint author), TJNAF, Newport News, VA 23606 USA. NR 31 TC 4 Z9 4 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD DEC PY 2001 VL 64 IS 6 AR 064602 DI 10.1103/PhysRevC.64.064602 PG 12 WC Physics, Nuclear SC Physics GA 502FL UT WOS:000172733000031 ER PT J AU Hafidi, K Lee, TSH AF Hafidi, K Lee, TSH TI Dynamical study of the H-2(e,e 'pi(+)) reaction SO PHYSICAL REVIEW C LA English DT Article ID SCATTERING AB The H-2(e,e'-pi (+)) reaction in parallel kinematics has been investigated using it dynamical model of pion electroproduction on the nucleon. A unitary pi NN model has been used in order to examine the effects due to the final two-nucleon interactions, pion rescattering from the second nucleon, and intermediate NN and N Delta interactions. It has been found that these pi NN mechanisms are small, but they can have significant contributions to the H-2(e,e' pi (+)) cross sections through their interference with the dominant impulse term, For the longitudinal cross sections, the effects due to the interference between the pion pole term and other production mechanisms are also found to be very large. Our findings clearly indicate that these interference effects must be accounted for in any attempt to determine from the H-2(e,e' pi (+)) data whether the pion form factor and/or pi NN vertex of the pion pole term are modified in the nuclear medium. C1 Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. RP Hafidi, K (reprint author), Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. NR 5 TC 7 Z9 7 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD DEC PY 2001 VL 64 IS 6 AR 064607 DI 10.1103/PhysRevC.64.064607 PG 5 WC Physics, Nuclear SC Physics GA 502FL UT WOS:000172733000036 ER PT J AU Jenkins, DG Balamuth, DP Carpenter, MP Lister, CJ Fischer, SM Clark, RM Macchiavelli, AO Fallon, P Svensson, CE Kelsall, NS Wadsworth, R AF Jenkins, DG Balamuth, DP Carpenter, MP Lister, CJ Fischer, SM Clark, RM Macchiavelli, AO Fallon, P Svensson, CE Kelsall, NS Wadsworth, R TI Stability of oblate shapes in the vicinity of N = Z=34 Se-68: Bands in Se-69 and As-67 SO PHYSICAL REVIEW C LA English DT Article ID IDENTIFICATION; NUCLEI; GE-65 AB The gamma -ray decay schemes of Se-69 and As-67 have been considerably extended using the Ca-40(S-32,2pn)Se-69 and Ca-40(S-32,alphap)As-67 reactions at 100 MeV and Ca-40(Ar-36, alpha 2pn)Se-69 and Ca-40(Ar-36,2 alphap)As-67 reactions at 145 MeV, with the aim of studying oblate bands arising from the strong coupling of a valence g(9/2) particle (or hole) to the oblate deformed ground state band of Se-68. A new T-1/2 = 12 +/- 2 ns J(pi) = 9/2(+) isomeric bandhead was identified in As-67. A transitional quadrupole moment of Q(0) = - 2.7(6) eb was deduced for the band built on the 9/2(+) isomer in Se-69, corresponding to a rigid oblate deformation of beta (2) = - 0.4(1), consistent with theoretical predictions. However, it appears that the relevant oblate configuration in Se-69 and As-67 are not nearly so favored as they are in Se-68, and are rapidly crossed by prolate configurations that form the high spin yrast lines. C1 Univ Penn, Dept Phys, Philadelphia, PA 19104 USA. Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. De Paul Univ, Dept Phys, Chicago, IL 60614 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. Univ York, Dept Phys, York YO1 5DD, N Yorkshire, England. RP Jenkins, DG (reprint author), Univ Penn, Dept Phys, Philadelphia, PA 19104 USA. RI Carpenter, Michael/E-4287-2015 OI Carpenter, Michael/0000-0002-3237-5734 NR 19 TC 23 Z9 24 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD DEC PY 2001 VL 64 IS 6 AR 064311 DI 10.1103/PhysRevC.64.064311 PG 8 WC Physics, Nuclear SC Physics GA 502FL UT WOS:000172733000019 ER PT J AU Karataglidis, S Chadwick, MB AF Karataglidis, S Chadwick, MB TI Microscopic optical potentials for nucleon-nucleus scattering SO PHYSICAL REVIEW C LA English DT Article ID NEUTRON ELASTIC-SCATTERING; MODEL; SHELL; ENERGIES; PROTONS AB Microscopic optical potentials for nucleon-nucleus (NA) scattering obtained from the folding of the effective g matrices, solutions of the Bruckner-Bethe-Goldstone equation, with the densities of the target, are applied to the case of neutron-nucleus scattering. Given that the optical potentials are specified in all two-body angular momentum, spin and isospin channels available to the NA scattering. the only difference in this model description of proton and neutron scattering observables for a given nucleus is ill the inclusion of the Coulomb interaction. A priori microscopic optical model predictions for neutron and proton elastic scattering are compared with results from a phenomenological optical model and with data. New measurements are recommended to reduce discrepancies in the existing database, and to differentiate between different theoretical predictions. C1 Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Karataglidis, S (reprint author), Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. NR 33 TC 8 Z9 8 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD DEC PY 2001 VL 64 IS 6 AR 064601 DI 10.1103/PhysRevC.64.064601 PG 7 WC Physics, Nuclear SC Physics GA 502FL UT WOS:000172733000030 ER PT J AU Koehler, PE Harvey, JA Winters, RR Guber, KH Spencer, RR AF Koehler, PE Harvey, JA Winters, RR Guber, KH Spencer, RR TI High-resolution neutron capture and transmission measurements for Sn-116,Sn-120, and their stellar neutron-capture cross sections at s-process temperatures SO PHYSICAL REVIEW C LA English DT Article ID RESONANCE SPECTROSCOPY; TIN ISOTOPES AB We have made high-resolution measurements of the neutron capture and total cross sections for Sn-116 and the neutron capture cross section for Sn-120 from 50 eV to 500 keV at the Oak Ridge Electron Linear Accelerator (ORELA). There have been no previously reported high-resolution measurements of these cross sections in this energy range. We performed an R-matrix analysis of our new data as well as previous total cross section data for Sn-120 to extract parameters for 216 resonances in Sn-117 between 100 eV and 30 keV. and 187 resonances in Sn-121 between 350 eV and 55 keV. These resonance parameters were used to calculate the average radiation widths, average level spacings, and strength functions for s- and p-wave neutron resonances. The Sn-116,Sn-120(n,gamma) astrophysical reaction rates were determined, to approximately 3% accuracy across the entire range of temperatures needed by the latest stellar models of the s process, from these resonance parameters together with our neutron capture measurements in the unresolved region. At the canonical s-process temperature of kT= 30 keV, our Sn-116(n,gamma) rate agrees to within the experimental uncertainties with the most recent high-precision measurement, and our Sn-120(n,gamma) rate resolves the discrepancy between two recent high-precision measurements. However, our measurements show that the most recently recommended reaction rates (which are based on extrapolations from previous measurements at higher energies) at kT= 6-8 keV, where most of the neutron exposure occurs in stellar s-process models, are too high by approximately 10-20%. We discuss the astrophysical impact of our new rates. C1 Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. Denison Univ, Dept Phys, Granville, OH 43023 USA. Oak Ridge Natl Lab, Computat Phys & Engn Div, Oak Ridge, TN 37831 USA. RP Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. OI Koehler, Paul/0000-0002-6717-0771 NR 34 TC 5 Z9 5 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9985 EI 2469-9993 J9 PHYS REV C JI Phys. Rev. C PD DEC PY 2001 VL 64 IS 6 AR 065802 DI 10.1103/PhysRevC.64.065802 PG 15 WC Physics, Nuclear SC Physics GA 502FL UT WOS:000172733000061 ER PT J AU Oganessian, YT Utyonkov, VK Lobanov, YV Abdullin, FS Polyakov, AN Shirokovsky, IV Tsyganov, YS Mezentsev, AN Iliev, S Subbotin, VG Sukhov, AM Buklanov, GV Subotic, K Lazarev, YA Moody, KJ Wild, JF Stoyer, NJ Stoyer, MA Lougheed, RW Laue, CA AF Oganessian, YT Utyonkov, VK Lobanov, YV Abdullin, FS Polyakov, AN Shirokovsky, IV Tsyganov, YS Mezentsev, AN Iliev, S Subbotin, VG Sukhov, AM Buklanov, GV Subotic, K Lazarev, YA Moody, KJ Wild, JF Stoyer, NJ Stoyer, MA Lougheed, RW Laue, CA TI Average charge states of heavy atoms in dilute hydrogen SO PHYSICAL REVIEW C LA English DT Article ID SUPERHEAVY NUCLEI; CA-48+PU-244 REACTION; IONS; DECAY; N=162 AB We measured the average electronic charge (q) of heavy ions with atomic numbers Z = 89 through 116. traversing dilute hydrogen gas with velocities ranging from I to 2.6 tinies the Bohr velocity. We observe a strong linear dependence of the average charge on the velocity of the ions, and only a weak dependence oil their atomic number Z. A more detailed examination of the experimental results shows that the (q) values reflect the influence of the 5f electron shell on the properties of these elements. C1 Joint Inst Nucl Res, RU-141980 Dubna, Russia. Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Utyonkov, VK (reprint author), Joint Inst Nucl Res, RU-141980 Dubna, Russia. NR 31 TC 13 Z9 13 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD DEC PY 2001 VL 64 IS 6 AR 064309 DI 10.1103/PhysRevC.64.064309 PG 6 WC Physics, Nuclear SC Physics GA 502FL UT WOS:000172733000017 ER PT J AU Smith, JF Lilley, JS Phillips, WR Ahmad, I Rehm, KE Garcia, A AF Smith, JF Lilley, JS Phillips, WR Ahmad, I Rehm, KE Garcia, A TI Lifetime of the 21.8-keV state in Tc-98 SO PHYSICAL REVIEW C LA English DT Article ID COINCIDENCE DATA SETS; NUCLEAR-EXCITATION; TRANSITION AB The lifetime of the 21.8-keV (5(+)) state in Tc-98 has been measured to be 3.5(9) ns by direct timing methods, using a BaF2 scintillator and a low-energy photon spectrometer. This state is of interest because it is expected to decay partially by bound internal conversion when the charge state of the technetium ion is 20 or greater. C1 Univ Manchester, Schuster Lab, Manchester M13 9PL, Lancs, England. Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. Univ Notre Dame, Dept Phys, Notre Dame, IN 46556 USA. RP Smith, JF (reprint author), Univ Manchester, Schuster Lab, Manchester M13 9PL, Lancs, England. NR 13 TC 0 Z9 0 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD DEC PY 2001 VL 64 IS 6 AR 067301 DI 10.1103/PhysRevC.64.067301 PG 4 WC Physics, Nuclear SC Physics GA 502FL UT WOS:000172733000065 ER PT J AU Szilner, S Nicoli, MP Basrak, Z Freeman, RM Haas, F Morsad, A Brandan, ME Satchler, GR AF Szilner, S Nicoli, MP Basrak, Z Freeman, RM Haas, F Morsad, A Brandan, ME Satchler, GR TI Refractive elastic scattering of carbon and oxygen nuclei: The mean field analysis and Airy structures SO PHYSICAL REVIEW C LA English DT Article ID O-16+C-12 SCATTERING; RESONANT BEHAVIOR; INCIDENT ENERGIES; O-16+O-16; POTENTIALS; C-12+C-12 AB The experimental data on the O-16 + C-12 and O-18 + C-12 elastic scatterings and their optical model analysis are presented. Detailed and complete elastic angular distributions have been measured at the Strasbourg Vivitron accelerator at several energies covering the energy range between 5 and 10 MeV per nucleon, The clastic scattering angular distributions show the usual diffraction pattern and also. at larger angles, refractive effects in the form of nuclear rainbow and associated Airy structures. The optical model analysis unambiguously the evolution of the refractive scattering pattern. The observed structure, namely the Airy minima, can be consistently described by a nucleus-nucleus potential with a deep real part and a weakly absorptive imaginary part. The difference in absorption in the two systems is explained by an increased imaginary (mostly surface) part of the potential in the O-18 + C-12 system. The relation between the obtained potentials and those reported for the symmetrical O-16 + O-16 and C-12 + C-12 systems is drawn. C1 Rudjer Boskovic Inst, HR-10002 Zagreb, Croatia. Inst Rech Subatom, CNRS, IN2P3, Strasbourg 2, France. Univ Strasbourg, F-67037 Strasbourg 2, France. Univ Hassan 2, Fac Sci Ben MSik, Casablanca, Morocco. Univ Nacl Autonoma Mexico, Inst Fis, Mexico City 01000, DF, Mexico. Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Rudjer Boskovic Inst, HR-10002 Zagreb, Croatia. RI Brandan, Maria-Ester/K-9014-2012 OI Brandan, Maria-Ester/0000-0002-1165-3440 NR 35 TC 29 Z9 29 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9985 EI 2469-9993 J9 PHYS REV C JI Phys. Rev. C PD DEC PY 2001 VL 64 IS 6 AR 064614 DI 10.1103/PhysRevC.64.064614 PG 11 WC Physics, Nuclear SC Physics GA 502FL UT WOS:000172733000043 ER PT J AU Wu, CY Cline, D Simon, MW Davis, GA Teng, R Macchiavelli, AO Vetter, K AF Wu, CY Cline, D Simon, MW Davis, GA Teng, R Macchiavelli, AO Vetter, K TI Electromagnetic properties of the rotationally aligned band in Dy-162 SO PHYSICAL REVIEW C LA English DT Article ID NUCLEI; FRAGMENTATION; TRANSITIONS; STRENGTH; MODEL AB Rotational band structures in Dy-161,Dy-164 were studied by projectile inelastic excitation on a Sn-118 target at near-barrier energies. States with spin up to 24(+) (22(+)) of the ground-state band and 18(+)(18(+)) of the gamma -vibrational band in Dy-162(Dy-164) were populated in these reactions States with spin spanning from 8(+) to 20(+) of the rotationally aligned S band in Dy-162 were populated by way of its band-crossing point with the gamma -vibrational band at spin 12(+), where strong mixing occurred due to an accidental degeneracy. This S band eventually crosses the ground-state band at spin 18(+) and becomes the yrast at spin 20(+). From the peripheral-collision gamma -ray yield data, sets of electromagnetic matrix elements for both the intraband and interband transitions were determined by using the Coulomb excitation code, GOSIA. The measured intraband E2 matrix elements were used to derive a quadrupole deformation of the S band that is approximate to 20% larger than those of the nearby low-lying collective bands. This represents the first measurement made for the quadrupole deformation of the S band for states well below the crossing point with the ground-state band. The two-phonon gamma -vibration harmonic strength in Dy-162 is highly fragmented, 36% of the strength is located in two K-pi = 4(+) bands at excitation energies 1535.9 and 2181.0 keV, respectively. Significant octupole collectivity was observed coupling the ground-state band to the K-pi = 2(-) band in Dy-162. C1 Univ Rochester, Dept Phys, Nucl Struct Res Lab, Rochester, NY 14627 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. RP Wu, CY (reprint author), Univ Rochester, Dept Phys, Nucl Struct Res Lab, 601 Elmwood Ave, Rochester, NY 14627 USA. NR 27 TC 18 Z9 19 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD DEC PY 2001 VL 64 IS 6 AR 064317 DI 10.1103/PhysRevC.64.064317 PG 9 WC Physics, Nuclear SC Physics GA 502FL UT WOS:000172733000025 ER PT J AU Afanasev, A Akushevich, I Merenkov, N AF Afanasev, A Akushevich, I Merenkov, N TI Model independent radiative corrections in processes of polarized electron-nucleon elastic scattering SO PHYSICAL REVIEW D LA English DT Article ID DEEP-INELASTIC SCATTERING; PROTON SCATTERING; ELECTROPRODUCTION; LEPTONS AB Explicit formulas for radiative correction (RC) calculations for elastic ep scattering are presented. Two typical measurements of polarization observables, such as beam-target asymmetry or recoil proton polarization, are considered. The possibilities of taking into account realistic experimental acceptances are discussed. The FORTRAN code MASCARAD for providing the RC procedure is presented. A numerical analysis is done for the kinematical conditions of CEBAF. C1 N Carolina Cent Univ, Durham, NC 27707 USA. TJNAF, Newport News, VA 23606 USA. Kharkov Phys & Technol Inst, UA-61108 Kharkov, Ukraine. RP Afanasev, A (reprint author), N Carolina Cent Univ, Durham, NC 27707 USA. NR 21 TC 35 Z9 35 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 1 PY 2001 VL 64 IS 11 AR 113009 DI 10.1103/PhysRevD.64.113009 PG 11 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 497JA UT WOS:000172450600019 ER PT J AU Aguilar, A Auerbach, LB Burman, RL Caldwell, DO Church, ED Cochran, AK Donahue, JB Fazely, A Garvey, GT Gunasingha, RM Imlay, R Louis, WC Majkie, R Malik, A Metcalf, W Mills, GB Sandberg, V Smith, D Stancu, I Sung, M Tayloe, R VanDalen, GJ Vernon, W Wadia, N White, DH Yellin, S AF Aguilar, A Auerbach, LB Burman, RL Caldwell, DO Church, ED Cochran, AK Donahue, JB Fazely, A Garvey, GT Gunasingha, RM Imlay, R Louis, WC Majkie, R Malik, A Metcalf, W Mills, GB Sandberg, V Smith, D Stancu, I Sung, M Tayloe, R VanDalen, GJ Vernon, W Wadia, N White, DH Yellin, S CA LSND Collaboration TI Evidence for neutrino oscillations from the observation of (nu)over-bar(c) appearance in a (nu)over-bar(mu) beam SO PHYSICAL REVIEW D LA English DT Article ID RANDOM-PHASE-APPROXIMATION; (NU)OVER-BAR(MU)->(NU)OVER-BAR(E) OSCILLATIONS; ATMOSPHERIC NEUTRINOS; STERILE NEUTRINOS; LSND EXPERIMENT; DARK-MATTER; SOLAR; C-12; SEARCH; DECAY AB A search for <()over bar>(mu) --><()over bar>(e) oscillations was conducted by the Liquid Scintillator Neutrino Detector at the Los Alamos Neutron Science Center using <()over bar>(mu) from mu (+) decay at rest. A total excess of 87.9+/-22.4+/-6.0 events consistent with <()over bar>(e)p-->e(+) n scattering was observed above the expected background. This excess corresponds to an oscillation probability of (0.264+/-0.067+/-0.045)%, which is consistent with an earlier analysis. In conjunction with other known limits on neutrino oscillations, the LSND data suggest that neutrino oscillations occur in the 0.2-10 eV(2)/c(4) Deltam(2) range, indicating a neutrino mass greater than 0.4 eV/c(2). C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Calif Riverside, Riverside, CA 92521 USA. Univ Calif San Diego, La Jolla, CA 92093 USA. Univ Calif Santa Barbara, Santa Barbara, CA 93106 USA. Embry Riddle Aeronaut Univ, Prescott, AZ USA. Louisiana State Univ, Baton Rouge, LA 70803 USA. So Univ, Baton Rouge, LA 70813 USA. Temple Univ, Philadelphia, PA 19122 USA. RP Aguilar, A (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 46 TC 957 Z9 959 U1 2 U2 9 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 1 PY 2001 VL 64 IS 11 AR 112007 DI 10.1103/PhysRevD.64.112007 PG 22 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 497JA UT WOS:000172450600010 ER PT J AU Airapetian, A Akopov, N Amarian, M Aschenauer, 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 Bouwhuis, M Brack, J Brauksiepe, S Braun, B Bray, B Brons, S Bruckner, W Brull, A Bruins, EEW Bulten, HJ 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 Ely, J Fantoni, A Fechtchenko, A Ferstl, M Fiedler, K Filippone, BW Fischer, H Fox, B Franz, J Frullani, S Funk, MA Garber, Y Gao, H Garibaldi, F Gavrilov, G Geiger, P Gharibyan, V Golendukhin, A Graw, G Grebeniouk, O Green, PW Greeniaus, LG Grosshauser, C Guidal, M Gute, A Gyurjyan, V Haas, JP Haeberli, W Hausser, O Hansen, JO Hartig, M Hasch, D Heinsius, FH Henderson, R Henoch, M Hertenberger, R Holler, Y Holt, RJ Hoprich, W Ihssen, H Iodice, M Izotov, A Jackson, HE Jgoun, A 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 Krivokhijine, VG Kurisuno, M Kyle, G Lachnit, W Lenisa, P Lorenzon, W Makins, NCR Manaenkov, SI Martens, FK Martin, JW 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 Most, A Muccifora, V Mussa, R Nagaitsev, A Naryshkin, Y Nathan, AM Neunreither, F Niczyporuk, JM Nowak, WD Nupieri, M O'Neill, TG Openshaw, R 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 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 Thomas, E Tipton, B Tytgat, M Urciuoli, GM van den Brand, JFJ van der Steenhoven, G van de Vyver, R van Hunen, JJ Vetterli, MC Vikhrov, V Vincter, MG Visser, J Volk, E Wander, W Wendland, J Williamson, SE Wise, T Woller, K Yoneyama, S Zohrabian, H AF Airapetian, A Akopov, N Amarian, M Aschenauer, 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 Bouwhuis, M Brack, J Brauksiepe, S Braun, B Bray, B Brons, S Bruckner, W Brull, A Bruins, EEW Bulten, HJ 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 Ely, J Fantoni, A Fechtchenko, A Ferstl, M Fiedler, K Filippone, BW Fischer, H Fox, B Franz, J Frullani, S Funk, MA Garber, Y Gao, H Garibaldi, F Gavrilov, G Geiger, P Gharibyan, V Golendukhin, A Graw, G Grebeniouk, O Green, PW Greeniaus, LG Grosshauser, C Guidal, M Gute, A Gyurjyan, V Haas, JP Haeberli, W Hausser, O Hansen, JO Hartig, M Hasch, D Heinsius, FH Henderson, R Henoch, M Hertenberger, R Holler, Y Holt, RJ Hoprich, W Ihssen, H Iodice, M Izotov, A Jackson, HE Jgoun, A 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 Krivokhijine, VG Kurisuno, M Kyle, G Lachnit, W Lenisa, P Lorenzon, W Makins, NCR Manaenkov, SI Martens, FK Martin, JW 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 Most, A Muccifora, V Mussa, R Nagaitsev, A Naryshkin, Y Nathan, AM Neunreither, F Niczyporuk, JM Nowak, WD Nupieri, M O'Neill, TG Openshaw, R 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 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 Thomas, E Tipton, B Tytgat, M Urciuoli, GM van den Brand, JFJ van der Steenhoven, G van de Vyver, R van Hunen, JJ Vetterli, MC Vikhrov, V Vincter, MG Visser, J Volk, E Wander, W Wendland, J Williamson, SE Wise, T Woller, K Yoneyama, S Zohrabian, H CA HERMES Collaboration TI Measurement of longitudinal spin transfer to Lambda hyperons in deep-inelastic lepton scattering SO PHYSICAL REVIEW D LA English DT Article ID POLARIZED QUARK DISTRIBUTIONS; STRUCTURE-FUNCTION G(1)(P); MUON SCATTERING; (LAMBDA)OVER-BAR POLARIZATION; Z-DECAYS; PROTON; DEUTERON; ASYMMETRIES; NUCLEON; BARYONS AB Spin transfer in deep-inelastic Lambda electroproduction has been studied with the HERMES detector using the 27.6 GeV polarized positron beam in the DESY HERA storage ring. For an average fractional energy transfer [z] = 0.45, the longitudinal spin transfer from the virtual photon to the Lambda has been extracted. The spin transfer along the Lambda momentum direction is found to be 0.11+/-0.17(stat)+/-0.03(syst); similar values are found for other possible choices for the longitudinal spin direction of the Lambda. This result is the most precise value obtained to date from deep-inelastic scattering with charged lepton beams, and is sensitive to polarized up quark fragmentation to hyperon states. The experimental result is found to be in general agreement with various models of the Lambda spin content, and is consistent with the assumption of helicity conservation in the fragmentation process. C1 Yerevan Phys Inst, Yerevan 375036, Armenia. 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 Zeuthen, D-15738 Zeuthen, Germany. Joint Inst Nucl Res, Dubna 141980, Russia. Univ Erlangen Nurnberg, Inst Phys, D-91058 Erlangen, Germany. Ist Nazl Fis Nucl, Sez Ferrara, I-44100 Ferrara, Italy. 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. 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, 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, 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; Messier, Claude/A-2322-2008; Kozlov, Valentin/M-8000-2015; Terkulov, Adel/M-8581-2015; Cisbani, Evaristo/C-9249-2011; OI Messier, Claude/0000-0002-4791-1763; Cisbani, Evaristo/0000-0002-6774-8473; Heinsius, Fritz-Herbert/0000-0002-9545-5117 NR 37 TC 44 Z9 45 U1 1 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 1 PY 2001 VL 64 IS 11 AR 112005 DI 10.1103/PhysRevD.64.112005 PG 7 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 497JA UT WOS:000172450600008 ER PT J AU Aitala, EM Amato, S Anjos, JC Appel, JA Ashery, D Banerjee, S Bediaga, I Blaylock, G Bracker, SB Burchat, PR Burnstein, RA Carter, T Carvalho, HS Copty, NK Cremaldi, LM Darling, C Denisenko, K Devmal, S Fernandez, A Fox, GF Gagnon, P Gerzon, S Gobel, C Gounder, K Halling, AM Herrera, G Hurvits, G James, C Kasper, PA Kwan, S Langs, DC Leslie, J Lichtenstadt, J Lundberg, B MayTal-Beck, S Meadows, B Neto, JRTD Mihalcea, D Milburn, RH de Miranda, JM Napier, A Nguyen, A d'Oliveira, AB O'Shaughnessy, K Peng, KC Perera, LP Purohit, MV Quinn, B Radeztsky, S Rafatian, A Reay, NW Reidy, JJ dos Reis, AC Rubin, HA Sanders, DA Santha, AKS Santoro, AFS Schwartz, AJ Sheaff, M Sidwell, RA Slaughter, AJ Sokoloff, MD Solano, J Stanton, NR Stefanski, RJ Stenson, K Summers, DJ Takach, S Thorne, K Tripathi, AK Watanabe, S Weiss-Babai, R Wiener, J Witchey, N Wolin, E Yang, SM Yi, D Yoshida, S Zaliznyak, R Zhang, C AF Aitala, EM Amato, S Anjos, JC Appel, JA Ashery, D Banerjee, S Bediaga, I Blaylock, G Bracker, SB Burchat, PR Burnstein, RA Carter, T Carvalho, HS Copty, NK Cremaldi, LM Darling, C Denisenko, K Devmal, S Fernandez, A Fox, GF Gagnon, P Gerzon, S Gobel, C Gounder, K Halling, AM Herrera, G Hurvits, G James, C Kasper, PA Kwan, S Langs, DC Leslie, J Lichtenstadt, J Lundberg, B MayTal-Beck, S Meadows, B Neto, JRTD Mihalcea, D Milburn, RH de Miranda, JM Napier, A Nguyen, A d'Oliveira, AB O'Shaughnessy, K Peng, KC Perera, LP Purohit, MV Quinn, B Radeztsky, S Rafatian, A Reay, NW Reidy, JJ dos Reis, AC Rubin, HA Sanders, DA Santha, AKS Santoro, AFS Schwartz, AJ Sheaff, M Sidwell, RA Slaughter, AJ Sokoloff, MD Solano, J Stanton, NR Stefanski, RJ Stenson, K Summers, DJ Takach, S Thorne, K Tripathi, AK Watanabe, S Weiss-Babai, R Wiener, J Witchey, N Wolin, E Yang, SM Yi, D Yoshida, S Zaliznyak, R Zhang, C CA Fermilab E791 Collaboration TI Study of the decay D-0 -> K-K-K+pi(+) SO PHYSICAL REVIEW D LA English DT Article ID PARTICLES; MESONS AB Using data from the E791 fixed-target hadroproduction experiment at Fermilab, we have studied the Cabibbo-favored but phase-space-suppressed decay D-0-->K- K- K+ pi (+). We find the decay rate for this mode to be (0.54+/-0.16+/-0.08) x 10(-2) times that for the normalization mode D-0-->K- pi (-) pi (+) pi (+). We observe a clear signal for D-0-->phiK(-) pi (+) which is consistent with producing 0.7+/-0.3 of the D-0-K- K- K+ pi (+) signal. In the context of simple models, we use our measurements to estimate the importance of decay amplitudes that produce extra quark-antiquark pairs from the vacuum relative to those that do not. C1 Univ Mississippi Oxford, University, MS 38677 USA. Ctr Brasileiro Pesquisas Fis, Rio De Janeiro, Brazil. Univ Calif Santa Cruz, Santa Cruz, CA 95064 USA. Univ Cincinnati, Cincinnati, OH 45221 USA. CINVESTAV, Mexico City 14000, DF, Mexico. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. IIT, Chicago, IL 60616 USA. Kansas State Univ, Manhattan, KS 66506 USA. Univ Massachusetts, Amherst, MA 01003 USA. Princeton Univ, Princeton, NJ 08544 USA. Univ Autonoma Puebla, Puebla 72570, Mexico. Univ S Carolina, Columbia, SC 29208 USA. Stanford Univ, Stanford, CA 94305 USA. Tel Aviv Univ, IL-69978 Tel Aviv, Israel. Tufts Univ, Medford, MA 02155 USA. Univ Wisconsin, Madison, WI 53706 USA. Yale Univ, New Haven, CT 06511 USA. RP Aitala, EM (reprint author), Univ Mississippi Oxford, University, MS 38677 USA. RI Anjos, Joao/C-8335-2013; Gobel Burlamaqui de Mello, Carla /H-4721-2016; Fernandez Tellez, Arturo/E-9700-2017 OI Gobel Burlamaqui de Mello, Carla /0000-0003-0523-495X; Fernandez Tellez, Arturo/0000-0003-0152-4220 NR 12 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 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD DEC 1 PY 2001 VL 64 IS 11 AR 112003 DI 10.1103/PhysRevD.64.112003 PG 8 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 497JA UT WOS:000172450600006 ER PT J AU Alavi-Harati, A Alexopoulos, T Arenton, M Arisaka, K Averitte, S Barbosa, RF Barker, AR Barrio, M Bellantoni, L Bellavance, A Belz, J Ben-David, R Bergman, DR Blucher, E Bock, GJ Bown, C Bright, S Cheu, E Childress, S Coleman, R Corcoran, MD Corti, G Cox, B Crisler, MB Erwin, AR Ford, R Glazov, A Golossanov, A Graham, G Graham, J Hagan, K Halkiadakis, E Hamm, J Hanagaki, K Hidaka, S Hsiung, YB Jejer, V Jensen, DA Kessler, R Kobrak, HGE LaDue, J Lath, A Ledovskoy, A McBride, PL Mikelsons, P Monnier, E Nakaya, T Nelson, KS Nguyen, H O'Dell, V Pang, M Pordes, R Prasad, V Qi, XR Quinn, B Ramberg, EJ Ray, RE Roodman, A Sadamoto, M Schnetzer, S Senyo, K Shanahan, P Shawhan, PS Shields, J Slater, W Solomey, N Somalwar, SV Stone, RL Swallow, EC Taegar, SA Tesarek, RJ Thomson, GB Toale, PA Tripathi, A Tschirhart, R Turner, SE Wah, YW Wang, J White, HB Whitmore, J Winstein, B Winston, R Yamanaka, T Zimmerman, ED AF Alavi-Harati, A Alexopoulos, T Arenton, M Arisaka, K Averitte, S Barbosa, RF Barker, AR Barrio, M Bellantoni, L Bellavance, A Belz, J Ben-David, R Bergman, DR Blucher, E Bock, GJ Bown, C Bright, S Cheu, E Childress, S Coleman, R Corcoran, MD Corti, G Cox, B Crisler, MB Erwin, AR Ford, R Glazov, A Golossanov, A Graham, G Graham, J Hagan, K Halkiadakis, E Hamm, J Hanagaki, K Hidaka, S Hsiung, YB Jejer, V Jensen, DA Kessler, R Kobrak, HGE LaDue, J Lath, A Ledovskoy, A McBride, PL Mikelsons, P Monnier, E Nakaya, T Nelson, KS Nguyen, H O'Dell, V Pang, M Pordes, R Prasad, V Qi, XR Quinn, B Ramberg, EJ Ray, RE Roodman, A Sadamoto, M Schnetzer, S Senyo, K Shanahan, P Shawhan, PS Shields, J Slater, W Solomey, N Somalwar, SV Stone, RL Swallow, EC Taegar, SA Tesarek, RJ Thomson, GB Toale, PA Tripathi, A Tschirhart, R Turner, SE Wah, YW Wang, J White, HB Whitmore, J Winstein, B Winston, R Yamanaka, T Zimmerman, ED CA KTeV Collaboration TI New measurement of the radiative Ke3 branching ratio and photon spectrum SO PHYSICAL REVIEW D LA English DT Article ID DECAYS AB We present a new measurement of the branching ratio of the decay K-L-->pi (+/-) e(-/+) nu (e)gamma (K-e3 gamma) with respect to K-L-->pi (-/+) e(-/+) nu (e) (K(e)3), and the first study of the photon energy spectrum in this decay. We find BR (K-e3 gamma,E-gamma* > 30 MeV, theta (e gamma)* > 20 degrees)/BR (K-e3) = 0.908+/-0.008(stat)(-0.012)(+0.013)(syst)%. Our measurement of the spectrum is consistent with inner bremsstrahlung as the only source of photons in K-e3 gamma. C1 Rutgers State Univ, Piscataway, NJ 08854 USA. Univ Arizona, Tucson, AZ 85721 USA. Univ Calif Los Angeles, Los Angeles, CA 90095 USA. Univ Calif San Diego, La Jolla, CA 92093 USA. Univ Chicago, Enrico Fermi Inst, Chicago, IL 60637 USA. Univ Colorado, Boulder, CO 80309 USA. Elmhurst Coll, Elmhurst, IL 60126 USA. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Osaka Univ, Osaka 5600043, Japan. Rice Univ, Houston, TX 77005 USA. Univ Virginia, Dept Phys, Charlottesville, VA 22901 USA. Univ Virginia, Inst Nucl & Particle Phys, Charlottesville, VA 22901 USA. Univ Wisconsin, Madison, WI 53706 USA. Univ Sao Paulo, Sao Paulo, Brazil. CNRS, CPP Marseille, Marseille, France. RP Bergman, DR (reprint author), Rutgers State Univ, Piscataway, NJ 08854 USA. EM dbergman@physics.rutgers.edu NR 10 TC 12 Z9 12 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 1 PY 2001 VL 64 IS 11 AR 112004 DI 10.1103/PhysRevD.64.112004 PG 7 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 497JA UT WOS:000172450600007 ER PT J AU Arkani-Hamed, N Hall, L Murayama, H Smith, D Weiner, N AF Arkani-Hamed, N Hall, L Murayama, H Smith, D Weiner, N TI Small neutrino masses from supersymmetry breaking SO PHYSICAL REVIEW D LA English DT Article ID LEPTON-FLAVOR VIOLATION; MATTER SEARCH CDMS; COLD DARK-MATTER; R-PARITY; STANDARD MODEL; STERILE NEUTRINO; HIGGS BOSONS; MU-PROBLEM; COLLIDERS; DECAYS AB An alternative to the conventional seesaw mechanism is proposed to explain the origin of small neutrino masses in supersymmetric theories. The masses and couplings of the right-handed neutrino field are suppressed by supersymmetry breaking, in a way similar to the suppression of the Higgs doublet mass mu. New mechanisms for light Majorana and Dirac neutrinos arise. depending on the degree of suppression. Super-partner phenomenology is greatly altered by the presence of weak scale right-handed sneutrinos, which may have a coupling to a Higgs boson and a left-handed sneutrino. The sneutrino spectrum and couplings are quite unlike the conventional case-the lightest sneutrino can be the dark matter and predictions are given for event rates at upcoming halo dark matter direct detection experiments. Higgs boson decays and search strategies are changed. Copious Higgs boson production at hadron colliders can result from cascade decays of squarks and gluinos. C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Ernest Orlando Lawrence Berkeley Natl Lab, Theoret Phys Grp, Berkeley, CA 94720 USA. RP Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. RI Murayama, Hitoshi/A-4286-2011 NR 59 TC 137 Z9 138 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0010 EI 2470-0029 J9 PHYS REV D JI Phys. Rev. D PD DEC 1 PY 2001 VL 64 IS 11 AR 115011 DI 10.1103/PhysRevD.64.115011 PG 15 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 497JA UT WOS:000172450600073 ER PT J AU Bauer, CW Chiang, CW Fleming, S Leibovich, AK Low, I AF Bauer, CW Chiang, CW Fleming, S Leibovich, AK Low, I TI Resumming the color-octet contribution to radiative Y decay SO PHYSICAL REVIEW D LA English DT Article ID RENORMALIZATION-GROUP; V-UB; QCD; QUARKONIUM; ANNIHILATION; SPECTRUM; GLUONS AB At the upper end point of the photon energy spectrum in Y-->X gamma, the standard NRQCD power counting breaks down and the OPE gives rise to color-octet structure functions. Furthermore, in this kinematic regime large Sudakov logarithms appear in the octet Wilson coefficients. The end point spectrum can be treated consistently within the framework of a recently developed effective field theory of collinear and soft particles. Here we show that within this approach the octet structure functions arise naturally and that Sudakov logarithms can be summed using the renormalization group equations. We derive an expression for the resummed energy spectrum and, using a model light cone structure function, investigate the phenomenological importance of the resummation. C1 Univ Calif San Diego, Dept Phys, La Jolla, CA 92093 USA. Carnegie Mellon Univ, Dept Phys, Pittsburgh, PA 15213 USA. Fermilab Natl Accelerator Lab, Theory Grp, Batavia, IL 60510 USA. RP Univ Calif San Diego, Dept Phys, La Jolla, CA 92093 USA. RI Fleming, Sean/C-3677-2015; OI Fleming, Sean/0000-0002-9553-7198; Chiang, Cheng-Wei/0000-0003-1716-0169 NR 28 TC 34 Z9 34 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0010 EI 2470-0029 J9 PHYS REV D JI Phys. Rev. D PD DEC 1 PY 2001 VL 64 IS 11 AR 114014 DI 10.1103/PhysRevD.64.114014 PG 10 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 497JA UT WOS:000172450600041 ER PT J AU Bauer, CW Ligeti, Z Luke, M AF Bauer, CW Ligeti, Z Luke, M TI Precision determination of vertical bar Vub vertical bar from inclusive decays SO PHYSICAL REVIEW D LA English DT Article ID SEMILEPTONIC B-DECAYS; TO-LEADING ORDER; Y-SUM-RULES; V-UB; PHOTON SPECTRUM; MASS-SPECTRUM; HEAVY QUARKS; NONPERTURBATIVE CORRECTIONS; LEPTON SPECTRUM; QCD CORRECTIONS AB We propose determining \V-ub\ from inclusive semileptonic B decay Using combined cuts on the leptonic and hadronic invariant masses to eliminate the b-c background. Compared to a pure dilepton invariant mass cut, the uncertainty from unknown order A(QCD)(3)/m(b)(3) terms in the operator product expansion is significantly reduced and the fraction of b-u events is roughly doubled. Compared to a pure hadronic invariant mass cut, the uncertainty from the unknown light-cone distribution function of the b quark is significantly reduced. We find that \V-ub\ can be determined with theoretical uncertainty at the 5-10% level. C1 Univ Calif San Diego, Dept Phys, La Jolla, CA 92093 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Toronto, Dept Phys, Toronto, ON M5S 1A7, Canada. RP Univ Calif San Diego, Dept Phys, La Jolla, CA 92093 USA. NR 51 TC 90 Z9 90 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0010 EI 2470-0029 J9 PHYS REV D JI Phys. Rev. D PD DEC 1 PY 2001 VL 64 IS 11 AR 113004 DI 10.1103/PhysRevD.64.113004 PG 10 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 497JA UT WOS:000172450600014 ER PT J AU Bodwin, GT Chen, YQ AF Bodwin, GT Chen, YQ TI Resummation of QCD corrections to the eta(c) decay rate SO PHYSICAL REVIEW D LA English DT Article ID QUANTUM CHROMODYNAMICS; QUARKONIUM; ANNIHILATION; RENORMALONS; AMBIGUITIES AB We examine the ratio of the decay rate of the eta, into light hadrons to the decay rate into photons and find that most of the large next-to-leading-order (NLO) correction is associated with running of the strong coupling alpha We resum Such contributions by analyzing final-state chains of vacuum-polarization bubbles. We show that the nonperturbative parts of the bubble chains can be absorbed into a color-octet matrix element, once one has used contour deformations, of the phase-space integrals to cancel certain contributions. We argue that these contributions are incompatible with the uncertainty principle, We also argue that perturbation theory is reliable only if one carries out the phase-space integrations before the perturbation summation. Our results are in good agreement with experiment and differ considerably from those that one obtains by applying the scale-setting method of Brodsky. Lepage. and Mackenzie to the NLO result. C1 Argonne Natl Lab, Div High Energy Phys, Argonne, IL 60439 USA. Acad Sinica, Inst Theoret Phys, Beijing 100080, Peoples R China. RP Argonne Natl Lab, Div High Energy Phys, Argonne, IL 60439 USA. NR 18 TC 7 Z9 7 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0010 EI 2470-0029 J9 PHYS REV D JI Phys. Rev. D PD DEC 1 PY 2001 VL 64 IS 11 AR 114008 DI 10.1103/PhysRevD.64.114008 PG 16 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 497JA UT WOS:000172450600035 ER PT J AU Brodsky, SJ Hiller, JR McCartor, G AF Brodsky, SJ Hiller, JR McCartor, G TI Application of Pauli-Villars regularization and discretized light-cone quantization to a single-fermion truncation of Yukawa theory SO PHYSICAL REVIEW D LA English DT Article ID ONE TIME DIMENSION; SINE-GORDON MODEL; FIELD-THEORY; PERTURBATION-THEORY; FRONT QUANTIZATION; YANG-MILLS; ONE SPACE; QCD; POSITRONIUM; MATRICES AB We apply Pauli-Villars regularization and discretized light-cone quantization to the nonperturbative solution of (3 + 1)-dimensional Yukawa theory in a single-fermion truncation. Three heavy scalars, including two with negative norm, are used to regulate the theory. The matrix eigenvalue problem is solved for the lowest-mass state with use of a new, indefinite-metric Lanczos algorithm. Various observables are extracted from the wave functions, including average multiplicities and average momenta of constituents, structure functions, and a form factor slope. C1 Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. Univ Minnesota, Dept Phys, Duluth, MN 55812 USA. So Methodist Univ, Dept Phys, Dallas, TX 75275 USA. RP Brodsky, SJ (reprint author), Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. NR 67 TC 25 Z9 25 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 1 PY 2001 VL 64 IS 11 AR 114023 DI 10.1103/PhysRevD.64.114023 PG 13 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 497JA UT WOS:000172450600050 ER PT J AU Cheng, HY Soni, A AF Cheng, HY Soni, A TI Phenomenological applications of QCD factorization to semi-inclusive B decays and direct CP violation SO PHYSICAL REVIEW D LA English DT Article ID HEAVY-QUARK; PSEUDOSCALAR MESONS; STANDARD MODEL; 2-BODY DECAYS; CHARM CONTENT; LIGHT MESONS; WEAK DECAYS; ETA' MESON; MECHANISM; CONSTANTS AB We systematically investigate the semi-inclusive B decals B-->MX, which are manifestations of the quark decay b-->Mq, within a framework inspired by QCD-improved factorization. These decays are theoretically clean and have distinctive experimental signatures. We focus on a class of these that do not require any form factor information, and therefore may be especially suitable for extracting information on the angles alpha and gamma of the unitarity triangle. The nonfactorizable effects, such as vertex-type and penguin-type corrections to the two-body b decay, b --> Mq, and hard spectator corrections to the three-body decay B --> Mq(1)(q) over bar (2) are calculable in the heavy quark limit. QCD factorization is applicable when the emitted meson is a light meson or a charmonium. We discuss the issue of the CPT constraint on partial rate asymmetries. The strong phase coming from final-state rescattering due to hard gluon exchange between the final states can induce large rate asymmetries for tree-dominated color-suppressed modes (pi (o), rho (o), omega )X-s(-). The nonfactorizable hard spectator interactions in the three-body decay B-->Mq(1)(q) over bar (2), though phase-space suppressed, are extremely important for the tree-dominated modes (pi (o), rho (o), omega )X-s(-), phiX, J/psiX(s), J/psiX and the penguin-dominated mode omegaX(ss)(-). In fact, they are dominated by the hard spectator corrections. This is because the relevant hard spectator interaction is color allowed, whereas the two-body semi-inclusive decays for these modes are color suppressed. Our result for B(B-->J/psiX(s)) is in agreement with experiment. The semi-inclusive decay modes (B) over bar (o)(s)--> (pi (o),rho (o), omega )X-s(-), rho X-o(ss)-, (B) over bar (o) -->(K-X, K*X-), and B- -->((KXs)-X-o, (KXs)-X-*o) are the most promising ones in searching for direct CP violation. In fact, they have branching ratios of order 10(-6) - 10(-4) and CP rate asymmetries of order (10-40)%. The decays (B) over bar (o)(s)--> (pi (o), rho (o), omega )X-ss(-) and B--->phiX are electroweak-penguin dominated. Some of them have sizable branching ratios and observable CP asymmetries. C1 Acad Sinica, Inst Phys, Taipei 115, Taiwan. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Cheng, HY (reprint author), Acad Sinica, Inst Phys, Taipei 115, Taiwan. NR 60 TC 9 Z9 9 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 1 PY 2001 VL 64 IS 11 AR 114013 DI 10.1103/PhysRevD.64.114013 PG 16 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 497JA UT WOS:000172450600040 ER PT J AU Di Pierro, M Eichten, E AF Di Pierro, M Eichten, E TI Excited heavy-light systems and hadronic transitions SO PHYSICAL REVIEW D LA English DT Article ID QUARK-MODEL; LATTICE QCD; MESONS; SPECTRUM; CHROMODYNAMICS; DECAYS; STATES AB A detailed study of orbital and radial excited states in D,D-s, B, and B-s systems is performed. The chiral quark model provides the framework for the calculation of pseudoscalar meson (pi ,K....) hadronic transitions among heavy-light excited and ground states. To calculate the excited states masses and wave functions, we must resort to a relativistic quark model. Our model includes the leading order corrections in 1/m((c,b)) (e.g., mixing). Numerical results for masses and light hadronic transition rates are compared to existing experimental data. The effective Coupling of the chiral quark model can be determined by comparing with independent results from lattice simulations (g(A)(8) =0.53 +/- 0.11) or fitting to known widths (g(A)(8) = 0.82 +/- 0.09). C1 Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. RP Di Pierro, M (reprint author), Fermilab Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. NR 34 TC 214 Z9 216 U1 1 U2 2 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 1 PY 2001 VL 64 IS 11 AR 114004 DI 10.1103/PhysRevD.64.114004 PG 20 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 497JA UT WOS:000172450600031 ER PT J AU Feng, JL Peskin, ME AF Feng, JL Peskin, ME TI Selectron studies at e(-)e(-) and e(+)e(-) colliders SO PHYSICAL REVIEW D LA English DT Article ID LINEAR COLLIDER; SUPERSYMMETRY; COLLISIONS; LUMINOSITY; SCATTERING; VIOLATION; PRECISION; PHYSICS; NLC AB Selectrons may be studied in both e(-) e(-) and e(+) e(-) collisions at future linear colliders. Relative to e(+) e(-), the e(-) e(-) mode benefits from negligible backgrounds and beta threshold behavior for identical selectron pair production, but suffers from luminosity degradation and increased initial state radiation and beamstrahlung. We include all of these effects and compare the potential for selectron mass measurements in the two modes. The virtues of the e(-) e(-) collider far outweigh its disadvantages. In particular, the electron mass may be measured to 100 MeV with a total integrated luminosity of 1 fb(-1), while more than 100 fb(-1) is required in e(+) e(-) collisions for similar precision. C1 MIT, Ctr Theoret Phys, Cambridge, MA 02139 USA. Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Feng, JL (reprint author), MIT, Ctr Theoret Phys, Cambridge, MA 02139 USA. EM jlf@mit.edu; mpeskin@slac.stanford.edu NR 35 TC 30 Z9 30 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 1 PY 2001 VL 64 IS 11 AR 115002 DI 10.1103/PhysRevD.64.115002 PG 8 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 497JA UT WOS:000172450600064 ER PT J AU Goncharov, M Adams, T Alton, A Bolton, T Goldman, J Spentzouris, P Conrad, J Fleming, BT Formaggio, J Koutsoliotas, S Kim, JH McNulty, C Romosan, A Shaevitz, MH Stern, EG Vaitaitis, A Zimmerman, ED Johnson, RA Vakili, M Suwonjandee, N Bernstein, RH Bugel, L Lamm, MJ Marsh, W Nienaber, P Yu, J de Barbaro, L Buchholz, D Schellman, H Zeller, GP Brau, J Drucker, RB Frey, R Mason, D McDonald, JE Naples, D Tzanov, M Avvakumov, S de Barbaro, P Bodek, A Budd, H Harris, DA McFarland, KS Sakumoto, WK Yang, UK AF Goncharov, M Adams, T Alton, A Bolton, T Goldman, J Spentzouris, P Conrad, J Fleming, BT Formaggio, J Koutsoliotas, S Kim, JH McNulty, C Romosan, A Shaevitz, MH Stern, EG Vaitaitis, A Zimmerman, ED Johnson, RA Vakili, M Suwonjandee, N Bernstein, RH Bugel, L Lamm, MJ Marsh, W Nienaber, P Yu, J de Barbaro, L Buchholz, D Schellman, H Zeller, GP Brau, J Drucker, RB Frey, R Mason, D McDonald, JE Naples, D Tzanov, M Avvakumov, S de Barbaro, P Bodek, A Budd, H Harris, DA McFarland, KS Sakumoto, WK Yang, UK TI Precise measurement of dimuon production cross sections in nu Fe-mu and (nu)over-bar(mu)Fe deep inelastic scattering at the Fermilab Tevatron SO PHYSICAL REVIEW D LA English DT Article ID OPPOSITE-SIGN DIMUONS; HEAVY QUARKS; NEUTRINO PRODUCTION; CHARMED PARTICLES; GLOBAL ANALYSIS; QCD ANALYSIS; NUCLEON; LEPTOPRODUCTION; SEA AB We present measurements of the semi-inclusive cross sections for nu (mu)- and <()over bar>(mu)-nucleon deep inelastic scattering interactions with two oppositely charged mucus in the final state. These events dominantly arise from the production of a charm quark during the scattering process. The measurement was obtained from the analysis of 5102 nu (mu)-induced and 1458 <()over bar>-induced events collected with the NuTeV detector exposed to a sign-selected beam at the Fermilab Tevatron. We also extract a cross-section measurement from a reanalysis of 5030 nu (mu)-induced and 1060 <()over bar>(mu)-induced events collected from the exposure of the same detector to a quad-triplet beam by the Chicago Columbia Fermilab Rochester (CCFR) experiment. The results are combined to obtain the most statistically precise measurement of neutrino-induced dimuon production cross sections to date. These measurements should be of broad use to phenomenologists interested in the dynamics of charm production, the strangeness content of the nucleon, and the Cabibbo-Kobayashi-Maskawa matrix element V-cd. C1 Kansas State Univ, Manhattan, KS 66506 USA. Columbia Univ, New York, NY USA. Univ Cincinnati, Cincinnati, OH USA. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Northwestern Univ, Evanston, IL USA. Univ Oregon, Eugene, OR 97403 USA. Univ Pittsburgh, Pittsburgh, PA USA. Univ Rochester, Rochester, NY USA. RP Goncharov, M (reprint author), Kansas State Univ, Manhattan, KS 66506 USA. RI Frey, Raymond/E-2830-2016 OI Frey, Raymond/0000-0003-0341-2636 NR 37 TC 179 Z9 179 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 1 PY 2001 VL 64 IS 11 AR 112006 DI 10.1103/PhysRevD.64.112006 PG 19 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 497JA UT WOS:000172450600009 ER PT J AU Hinchliffe, I Kersting, N AF Hinchliffe, I Kersting, N TI CP violation from noncommutative geometry SO PHYSICAL REVIEW D LA English DT Article ID ELECTRIC-DIPOLE MOMENT; QUANTUM-FIELD THEORY; EXPERIMENTAL LIMIT; GAUGE-THEORIES; DETECTOR; NEUTRON AB If the geometry of space-time is noncommutative, i.e,, [x(mu),x(nu)]=i theta (mu nu), then noncommutative CP violating effects may be manifest at low energies. For a noncommutative scale Lambda = theta (-1/2)less than or equal to2 TeV, CP violation from noncommutative geometry is comparable to that from the standard model alone: the noncommutative contributions to epsilon and epsilon'/epsilon in the K system may actually dominate over the standard model contributions. Present data permit noncommutative geometry to be the only source of CP violation. Furthermore the most recent findings for g-2 of the muon are consistent with predictions from noncommutative geometry. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Hinchliffe, I (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. NR 57 TC 37 Z9 37 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 1 PY 2001 VL 64 IS 11 AR 116007 DI 10.1103/PhysRevD.64.116007 PG 10 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 497JA UT WOS:000172450600087 ER PT J AU Kidonakis, N Laenen, E Moch, S Vogt, R AF Kidonakis, N Laenen, E Moch, S Vogt, R TI Sudakov resummation and finite order expansions of heavy quark hadroproduction cross sections SO PHYSICAL REVIEW D LA English DT Article ID SOFT-GLUON RESUMMATION; QCD HARD SCATTERING; HADRON HADRON-COLLISIONS; DIRECT PHOTON PRODUCTION; TOP-QUARK; LEADING ORDER; THRESHOLD RESUMMATION; PARTON DISTRIBUTIONS; FLAVOR PRODUCTION; NNLO CORRECTIONS AB We resum Sudakov threshold enhancements in heavy quark hadroproduction for single-heavy-qua-rk inclusive and pair-inclusive kinematics. We expand these resummed results and derive analytical finite-order cross sections through next-to-next-to-leading order. This involves the construction of next-to-leading order matching conditions in color space. For the scale dependent terms, we derive exact results using renormalization Group methods. We study the effects of scale variations, scheme and kinematics choice on the partonic and hadronic cross sections, and provide estimates for top and bottom quark production cross sections. C1 Florida State Univ, Dept Phys, Tallahassee, FL 32306 USA. NIKHEF H, Theory Grp, NL-1009 DB Amsterdam, Netherlands. Univ Karlsruhe, Inst Theoret Teilchenphys, D-76128 Karlsruhe, Germany. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. RP Kidonakis, N (reprint author), Florida State Univ, Dept Phys, Tallahassee, FL 32306 USA. NR 65 TC 114 Z9 114 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 1 PY 2001 VL 64 IS 11 AR 114001 DI 10.1103/PhysRevD.64.114001 PG 36 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 497JA UT WOS:000172450600028 ER PT J AU Stratmann, M Vogelsang, W AF Stratmann, M Vogelsang, W TI Towards a global analysis of polarized parton distributions SO PHYSICAL REVIEW D LA English DT Article ID TO-LEADING-ORDER; DEEP-INELASTIC-SCATTERING; DIRECT PHOTON PRODUCTION; SEMIINCLUSIVE SPIN ASYMMETRIES; HADRON-HADRON SCATTERING; N-C LIMIT; FRAGMENTATION FUNCTIONS; QUARK DISTRIBUTIONS; PERTURBATION-THEORY; LEPTON-HADRON AB We present a technique for implementing in a fast way, and without an approximations. higher-order calculations of partonic cross sections into global analyses of parton distribution functions. The approach, which is set up in Mellin-moment space, is particularly suited for analyses of future data from polarized proton-proton collisions, but not limited to this case. The usefulness and practicability of this method is demonstrated for the semi-inclusive production of hadrons in deep-inelastic scattering and the transverse momentum distribution of "prompt" photons in pp collisions, and a case study for a future global analysis of polarized parton densities is presented. C1 Univ Regensburg, Inst Theoret Phys, D-93040 Regensburg, Germany. SUNY Stony Brook, CN Yang Inst Theoret Phys, Stony Brook, NY 11794 USA. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Brookhaven Natl Lab, RIKEN BNL Res Ctr, Upton, NY 11973 USA. RP Stratmann, M (reprint author), Univ Regensburg, Inst Theoret Phys, D-93040 Regensburg, Germany. OI Stratmann, Marco/0000-0001-7125-8701 NR 55 TC 57 Z9 57 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 1 PY 2001 VL 64 IS 11 AR 114007 DI 10.1103/PhysRevD.64.114007 PG 10 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 497JA UT WOS:000172450600034 ER PT J AU Suzuki, M AF Suzuki, M TI Final-state interactions and s-quark helicity conservation in B -> J vertical bar psi K* SO PHYSICAL REVIEW D LA English DT Article ID HEAVY MESON DECAYS; SEMILEPTONIC DECAYS; QCD FACTORIZATION; FORM-FACTORS; B-DECAYS; AMPLITUDES; CHARMONIUM; PHASES; MODEL AB The latest BaBar Collaboration measurement has confirmed substantial strong phases for the B-J/psiK* decal amplitudes, implying violation of factorization in this decay mode. In the absence of a polarization measurement or a lepton pair from J/psi, however the relative phases of the spin amplitudes still have a twofold ambiguity. In one set of the allowed phases the s-quark helicity is conserved approximately despite final-state interactions. In the other set, the s-quark helicity is badly violated hy long-distance interactions. We cannot rule out the latter mince the validity of pertubative QCD is questionable for this decay. We examine the large final-state interactions vith a statistical model. Toward a resolution of the ambiguity without a lepton polarization measurement, we discuss the relevance of other B-l(-) l(-) decay modes that involve the same feature. C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Suzuki, M (reprint author), Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. NR 35 TC 23 Z9 23 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 1 PY 2001 VL 64 IS 11 AR 117503 DI 10.1103/PhysRevD.64.117503 PG 4 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 497JA UT WOS:000172450600099 ER PT J AU Abramson, G Bishop, AR Kenkre, VM AF Abramson, G Bishop, AR Kenkre, VM TI Effects of transport memory and nonlinear damping in a generalized Fisher's equation SO PHYSICAL REVIEW E LA English DT Article ID REACTION-DIFFUSION SYSTEMS; ALBEDO BOUNDARY-CONDITIONS; LOCALIZED PATTERNS; MARGINAL STABILITY; STATIONARY STATES; FRONT PROPAGATION; UNSTABLE STATES; SELECTION AB Memory effects in transport require, for their incorporation into reaction-diffusion investigations, a generalization of traditional equations. The well-known Fisher's equation, which combines diffusion with a logistic nonlinearity, is generalized to include memory effects, and traveling wave solutions of the equation are found. Comparison is made with alternative generalization procedures. C1 Univ New Mexico, Ctr Adv Studies, Albuquerque, NM 87131 USA. Univ New Mexico, Dept Phys & Astron, Albuquerque, NM 87131 USA. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Los Alamos Natl Lab, Ctr Nonlinear Studies, Los Alamos, NM 87545 USA. Ctr Atom Bariloche, Inst Balseiro, RA-8400 San Carlos De Bariloche, Rio Negro, Argentina. Consejo Nacl Invest Cient & Tecn, RA-8400 San Carlos De Bariloche, Rio Negro, Argentina. RP Abramson, G (reprint author), Univ New Mexico, Ctr Adv Studies, Albuquerque, NM 87131 USA. EM abramson@cab.cnea.gov.ar NR 20 TC 46 Z9 47 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1539-3755 J9 PHYS REV E JI Phys. Rev. E PD DEC PY 2001 VL 64 IS 6 AR 066615 DI 10.1103/PhysRevE.64.066615 PN 2 PG 6 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 502CP UT WOS:000172726400080 PM 11736304 ER PT J AU Alexander, FJ Boghosian, BM Brower, RC Kimura, SR AF Alexander, FJ Boghosian, BM Brower, RC Kimura, SR TI Fourier acceleration of Langevin molecular dynamics SO PHYSICAL REVIEW E LA English DT Article ID SIMULATIONS; SYSTEMS; EFFICIENT; SCHEME AB Fourier acceleration has been successfully applied to the simulation of lattice field theories for more than a decade. In this paper, we extend the method to the dynamics of discrete particles moving in a continuum. Although our method is based on a mapping of the particles' dynamics to a regular grid so that discrete Fourier transforms may be taken, it should be emphasized that the introduction of the grid is a purely algorithmic device and that no smoothing, coarse-graining, or mean-field approximations are made. The method thus can be applied to the equations of motion of molecular dynamics (MD) or its Langevin or Brownian variants. For example, in Langevin MD simulations our acceleration technique permits a straightforward spectral decomposition of forces so that the long-wavelength modes are integrated with a longer time step, thereby reducing the time required to reach equilibrium or to decorrelate the system in equilibrium. Speedup factors of up to 30 are observed relative to pure (unaccelerated) Langevin MD. As with acceleration of critical lattice models, even further gains relative to the unaccelerated method are expected for larger systems. Preliminary results for Fourier-accelerated molecular dynamics are presented in order to illustrate the basic concepts. Possible extensions of the method and further lines of research are discussed. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Boston Univ, Ctr Computat Sci, Boston, MA 02215 USA. Boston Univ, Dept Phys, Boston, MA 02215 USA. Boston Univ, Dept Biomed Engn, Boston, MA 02215 USA. RP Alexander, FJ (reprint author), Los Alamos Natl Lab, CCS-3,MS-B256, Los Alamos, NM 87545 USA. EM fja@lanl.gov; bruceb@bu.edu; brower@bucrf20.bu.edu; srk@engc.bu.edu NR 23 TC 3 Z9 3 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1539-3755 J9 PHYS REV E JI Phys. Rev. E PD DEC PY 2001 VL 64 IS 6 AR 066704 DI 10.1103/PhysRevE.64.066704 PN 2 PG 6 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 502CP UT WOS:000172726400086 PM 11736310 ER PT J AU Beiersdorfer, P Slater, M AF Beiersdorfer, P Slater, M TI Measurement of the electron cyclotron energy component of the electron beam of an electron beam ion trap SO PHYSICAL REVIEW E LA English DT Article ID DIELECTRONIC SATELLITE LINES; HIGHLY-CHARGED IONS; X-RAY TRANSITIONS; LITHIUM-LIKE IONS; HELIUM-LIKE; IMPACT EXCITATION; CROSS-SECTIONS; HE-LIKE; EMISSION-LINES; FE-XXV AB The energy component associated with the cyclotron motion of the beam electrons in the Livermore EBIT-II electron beam ion trap was inferred from measurements of the linear polarization of the K-shell x-ray lines emitted from heliumlike Mg(10+) ions. The average line polarization was found to be reduced by about 20% from its nominal value. From this it was inferred that the electron cyclotron motion accounted for 190 +/- 30 eV of the total electron beam energy. The measured value is in good agreement with the predictions of optical electron beam propagation. It does not agree with the estimates derived from other model assumptions, such as the rigid-rotator model, for determining the size of the energy stored in the electron motion perpendicular to the beam propagation direction. C1 Lawrence Livermore Natl Lab, Dept Phys & Adv Technol, Livermore, CA 94551 USA. Spelman Coll, Atlanta, GA 30314 USA. RP Beiersdorfer, P (reprint author), Lawrence Livermore Natl Lab, Dept Phys & Adv Technol, Livermore, CA 94551 USA. NR 39 TC 29 Z9 29 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1539-3755 J9 PHYS REV E JI Phys. Rev. E PD DEC PY 2001 VL 64 IS 6 AR 066408 DI 10.1103/PhysRevE.64.066408 PN 2 PG 6 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 502CP UT WOS:000172726400059 PM 11736283 ER PT J AU Choueiri, EY AF Choueiri, EY TI Instability of a current-carrying finite-beta collisional plasma SO PHYSICAL REVIEW E LA English DT Article ID HYBRID-DRIFT INSTABILITY; MODIFIED 2-STREAM INSTABILITY; FIELD STREAMING INSTABILITY; THRUSTERS AB The microinstability of a cross-field current-carrying plasma in which the electron collisions are important on the time scale of the oscillations and can be modeled with a Bhatnagar-Gross-Krook operator is studied using linearized kinetic theory under conditions of finite electron beta. The finiteness of beta allows for coupling between electrostatic and electromagnetic modes and necessitates dealing with the entire dispersion tensor. Fundamental features of the resulting instability are identified and contrasted with those found in previous Studies of the lower hybrid current-driven instability in which either collisions or finite-beta effects were neglected. As beta increases. collisions play a more important role in destabilization. alter the character and extent of electromagnetic coupling, shift the instability to more perpendicular modes, and lead to a recapturing of some of the fluidlike properties the modes have in the electrostatic limit in contrast with their highly kinetic character in the collisionless limit. C1 Princeton Univ, Elect Prop & Plasma Dynam Lab, Princeton, NJ 08544 USA. RP Princeton Univ, Elect Prop & Plasma Dynam Lab, Princeton, NJ 08544 USA. NR 40 TC 3 Z9 3 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0045 EI 2470-0053 J9 PHYS REV E JI Phys. Rev. E PD DEC PY 2001 VL 64 IS 6 AR 066413 DI 10.1103/PhysRevE.64.066413 PN 2 PG 11 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 502CP UT WOS:000172726400064 PM 11736288 ER PT J AU DiMasi, E Fossum, JO Gog, T Venkataraman, C AF DiMasi, E Fossum, JO Gog, T Venkataraman, C TI Orientational order in gravity dispersed clay colloids: A synchrotron x-ray scattering study of Na fluorohectorite suspensions SO PHYSICAL REVIEW E LA English DT Article ID NEMATIC-ISOTROPIC TRANSITION; PLATE-LIKE PARTICLES; THIN HARD PLATELETS; SMECTITE CLAYS; PHASE-DIAGRAM; GELATION; SYSTEMS AB Colloidal suspensions of clay particles in aqueous salt solutions make ideal model systems for the study of interactions between plate-shaped particles, due to the ease in tuning their electrostatic repulsion with the concentration of the salt. Numerous get and sol structures are possible, including nematic liquid crystalline order, although only qualitative identification of the latter in clay colloids has been available so far. We present synchrotron x-ray diffraction from gravity dispersed solutions of Na fluorohectorite, a synthetic swelling clay, over a large NaCl concentration range. Our use of liquid scattering techniques allows us to identify regions in which particles reorient from horizontal to vertical alignments in strata coexisting at different heights within the sample. We identify two distinct gel regions characterized by differences in orientational anisotropy and domain size. Our results provide direct evidence for nematic order, as well as unique structural information regarding particle morphology and alignment within each of the colloid phases. C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Norwegian Univ Sci & Technol, Dept Phys, N-7491 Trondheim, Norway. Argonne Natl Lab, Adv Photon Source, CMC CAT, Argonne, IL 60439 USA. RP DiMasi, E (reprint author), Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. EM dimasi@bnl.gov RI Fossum, Jon/L-1510-2016 OI Fossum, Jon/0000-0002-8952-303X NR 24 TC 43 Z9 43 U1 2 U2 10 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1063-651X J9 PHYS REV E JI Phys. Rev. E PD DEC PY 2001 VL 64 IS 6 AR 061704 DI 10.1103/PhysRevE.64.061704 PN 1 PG 7 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 502CN UT WOS:000172726300041 PM 11736199 ER PT J AU Geng, JF Longhi, E Behringer, RP Howell, DW AF Geng, JF Longhi, E Behringer, RP Howell, DW TI Memory in two-dimensional heap experiments SO PHYSICAL REVIEW E LA English DT Article ID SAND; SANDPILES AB The measurement of force distributions in sandpiles provides a useful way to test concepts and models of the way forces propagate within noncohesive granular materials. Recent theory [J.-P. Bouchaud, M.E. Cates, and P. Claudin, J. Phys. I 5, 639 (1995); M. E. Cates, J. P. Wittmer, J.-P. Bouchaud, and P. Claudin, Phil. Trans. Roy. Soc. 356, 2535 (1998)] by Bouchaud et al. implies that the internal structure of a heap (and therefore the force pathway) is a strong function of the construction history. In general, it is difficult to obtain information that could test this idea from three-dimensional granular experiments except at boundaries. However, two-dimensional systems, such as those used here, can yield information on forces and particle arrangements in the interior of a sample. We obtain position and force information through the use of photoelastic particles. These experiments show that the history of the heap formation has a dramatic effect on the arrangement of particles (texture) and a weaker but clear effect on the forces within the sample. Specifically, heaps prepared by pouring from a point source show strong anisotropy in the contact angle distribution. Depending on additional details, they show a stress dip near the center. Heaps formed from a broad source show relatively little contact angle anisotropy and no indication of a stress dip. C1 Duke Univ, Dept Phys, Durham, NC 27708 USA. Duke Univ, Ctr Nonlinear & Complex Syst, Durham, NC 27708 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Geng, JF (reprint author), Duke Univ, Dept Phys, Durham, NC 27708 USA. NR 26 TC 64 Z9 68 U1 1 U2 12 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1063-651X J9 PHYS REV E JI Phys. Rev. E PD DEC PY 2001 VL 64 IS 6 AR 060301 DI 10.1103/PhysRevE.64.060301 PN 1 PG 4 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 502CN UT WOS:000172726300003 PM 11736161 ER PT J AU Kerstein, AR AF Kerstein, AR TI Prandtl-number dependence of turbulent flame propagation SO PHYSICAL REVIEW E LA English DT Article ID BURNING VELOCITY; IA SUPERNOVAE; COMBUSTION; MODELS; SIMULATION; FRONT AB Inertial-range cascade phenomenology is used to predict Prandti-number (Pr) dependencies of turbulent flame properties. A unified picture of turbulent flame structure and burning velocity is developed that encompasses all Pr regimes. Implications of the analysis for gaseous flames (Pr near unity), autocatalytic fronts in liquids (high Pr), and astrophysical flames (low Pr) are noted. C1 Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA. RP Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA. NR 25 TC 10 Z9 10 U1 2 U2 5 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0045 EI 2470-0053 J9 PHYS REV E JI Phys. Rev. E PD DEC PY 2001 VL 64 IS 6 AR 066306 DI 10.1103/PhysRevE.64.066306 PN 2 PG 6 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 502CP UT WOS:000172726400051 PM 11580446 ER PT J AU Kevrekidis, PG Nistazakis, HE Frantzeskakis, DJ Malomed, BA Bishop, AR AF Kevrekidis, PG Nistazakis, HE Frantzeskakis, DJ Malomed, BA Bishop, AR TI Ring solitons on vortices SO PHYSICAL REVIEW E LA English DT Article ID MODE VECTOR SOLITONS; DARK SOLITONS; EQUATION; GENERATION; DYNAMICS; PULSONS AB Interaction of a ring dark or antidark soliton (RDS and RADS, respectively) with a vortex is considered in the defocusing nonlinear Schrodinger equation with cubic (for RDS) or saturable (for RADS) nonlinearities. By means of direct simulations, it is found that the interaction gives rise to either an almost isotropic or a spiral-like pattern. A transition between them occurs at a critical value of the RDS or RADS amplitude., the spiral pattern appearing if the amplitude exceeds the critical value. An initial ring soliton created on top of the vortex splits into a pair of rings moving inward and outward. In the subcritical case, the inbound ring reverses its polarity, bouncing from the vortex core, without conspicuous effect on the core. In the transcritical case, the bounced ring soliton suffers a spiral deformation, while the vortex changes its position and structure and also loses its axial symmetry. Through a variational-type approach to the system's Hamiltonian, we additionally find that the vortex-RDS and vortex-RADS interactions are, respectively, attractive and repulsive. Simulations with the vortex placed eccentrically with respect to the RDS or RADS reveal the generation of strongly localized multispot dark and/or antidark coherent structures. The occurrence of spiral-like patterns in many numerical experiments prompted an attempt to generate a spiral dark soliton, but the latter is found to suffer a core instability that converts it into a rotating dipole emitting waves in the outward direction. C1 Princeton Univ, Program Appl & Computat Math, Princeton, NJ 08544 USA. Los Alamos Natl Lab, Ctr Nonlinear Studies, Los Alamos, NM 87545 USA. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Univ Athens Panepistimiopolis, Dept Phys, Athens 15784, Greece. Tel Aviv Univ, Fac Engn, Dept Interdisciplinary Studies, IL-69978 Tel Aviv, Israel. RP Kevrekidis, PG (reprint author), Princeton Univ, Program Appl & Computat Math, Fine Hall,Washington Rd, Princeton, NJ 08544 USA. NR 24 TC 0 Z9 0 U1 1 U2 7 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1539-3755 J9 PHYS REV E JI Phys. Rev. E PD DEC PY 2001 VL 64 IS 6 AR 066611 DI 10.1103/PhysRevE.64.066611 PN 2 PG 9 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 502CP UT WOS:000172726400076 ER PT J AU Kevrekidis, PG Gaididei, YB Bishop, AR Saxena, A AF Kevrekidis, PG Gaididei, YB Bishop, AR Saxena, A TI Effects of competing short- and long-range dispersive interactions on discrete breathers SO PHYSICAL REVIEW E LA English DT Article ID INTRINSIC LOCALIZED MODES; CRYSTAL WAVE-GUIDES; NONLINEAR LATTICES; DNA DENATURATION; EXCITATIONS; THRESHOLDS AB The discrete nonlinear Schrodinger equation with competing short-range and long-range interactions is considered in spatial dimensions d greater than or equal to 2. This model equation is derived for a situation of two linearly coupled excitations (independently of dimension). and we analytically and numerically study its properties in 2 + 1 dimensions. We analyze theoretically and demonstrate numerically the dependence of the discrete breather solutions on the amplitude and range of the interactions. We find that complete suppression of the existence thresholds obtained recently for short-range interactions can be achieved beyond a critical value of the amplitude or of the range of the long-range kernel. For supercritical values of the corresponding parameters, staggered branches of solutions are obtained both in theory as well as in the numerical experiment. C1 Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Los Alamos Natl Lab, Ctr Nonlinear Studies, Los Alamos, NM 87545 USA. Bogolyubov Inst Theoret Phys, UA-252143 Kiev, Ukraine. RP Los Alamos Natl Lab, Div Theoret, MS B262, Los Alamos, NM 87545 USA. NR 44 TC 9 Z9 9 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0045 EI 2470-0053 J9 PHYS REV E JI Phys. Rev. E PD DEC PY 2001 VL 64 IS 6 AR 066606 DI 10.1103/PhysRevE.64.066606 PN 2 PG 8 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 502CP UT WOS:000172726400071 PM 11736295 ER PT J AU Schriber, SO AF Schriber, SO TI Analog analysis of pi-mode structures: Results and implications SO PHYSICAL REVIEW SPECIAL TOPICS-ACCELERATORS AND BEAMS LA English DT Article AB The cavities of choice for high- energy synchrotrons and for medium- beta and high- beta accelerating superconducting structures around the world are pi -mode structures. A coupled- circuit analysis, allowing for errors in cell frequencies and cell coupling constants, has been used to determine relative on- axis electric field amplitudes between cells, operating frequencies, end- cell tuning, relative on- axis field phase shifts, and field tilts when operated off resonance. Formulas are given for the above information as well as specific examples showing sensitivities and machining/ assembly/ control tolerances. A method to determine relative field amplitudes on the basis of the mode spectra was developed. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Schriber, SO (reprint author), Los Alamos Natl Lab, POB 1663,MS H820, Los Alamos, NM 87545 USA. NR 16 TC 2 Z9 2 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-4402 J9 PHYS REV SPEC TOP-AC JI Phys. Rev. Spec. Top.-Accel. Beams PD DEC PY 2001 VL 4 IS 12 BP art. no. EP 122001 PG 11 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 498AZ UT WOS:000172488800001 ER PT J AU Schriber, SO AF Schriber, SO TI One-step tuning algorithm for pi-mode cavities SO PHYSICAL REVIEW SPECIAL TOPICS-ACCELERATORS AND BEAMS LA English DT Article AB Cavities for pi -mode operation are used in existing accelerators and are being built for many future systems. One of the steps in cavity construction is tuning individual cells within the cavity to ensure that the absolute values of relative peak on- axis electric field amplitudes in each cell are equal. This process may have multiple iterative steps: measuring the on- axis fields using bead- pull techniques, employing tuning methods to perturb the cells, making cell adjustments, and then repeating the process on the basis of the new results. This paper describes a one- step process for an N cell cavity that provides the necessary adjustment for each cell to achieve equal field amplitude absolute values from one bead- pull measurement. In addition, a method is shown for inferring relative cell fields while a cavity is operational in an accelerator complex. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Schriber, SO (reprint author), Los Alamos Natl Lab, POB 1663,MS H820, Los Alamos, NM 87545 USA. NR 4 TC 1 Z9 1 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-4402 J9 PHYS REV SPEC TOP-AC JI Phys. Rev. Spec. Top.-Accel. Beams PD DEC PY 2001 VL 4 IS 12 BP art. no. EP 122002 PG 6 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 498AZ UT WOS:000172488800002 ER PT J AU Carr, R Cornacchia, M Emma, P Nuhn, HD Poling, B Ruland, R Johnson, E Rakowsky, G Skaritka, J Lidia, S Duffy, P Libkind, M Frigola, P Murokh, A Pellegrini, C Rosenzweig, J Tremaine, A AF Carr, R Cornacchia, M Emma, P Nuhn, HD Poling, B Ruland, R Johnson, E Rakowsky, G Skaritka, J Lidia, S Duffy, P Libkind, M Frigola, P Murokh, A Pellegrini, C Rosenzweig, J Tremaine, A TI Visible-infrared self-amplified spontaneous emission amplifier free electron laser undulator SO PHYSICAL REVIEW SPECIAL TOPICS-ACCELERATORS AND BEAMS LA English DT Article AB The visible-infrared self-amplified spontaneous emission amplifier (VISA) free electron laser (FEL) is an experimental device designed to show self-amplified spontaneous emission (SASE) to saturation in the near infrared to visible light energy range. It generates a resonant wavelength output from 800-600 nm, so that silicon detectors may be used to characterize the optical properties of the FEL radiation. VISA is designed to show how SASE FEL theory corresponds with experiment in this wavelength range, using an electron beam with emittance close to that planned for the future Linear Coherent Light Source at SLAC. VISA comprises a 4 m pure permanent magnet undulator with four 99 cm segments, each of 55 periods, 18 mm long. The undulator has distributed focusing built into it, to reduce the average beta function of the 70-85 MeV electron beam to about 30 cm. There are four FODO cells per segment. The permanent magnet focusing lattice consists of blocks mounted on either side of the electron beam, in the undulator gap. The most important undulator error parameter for a free electron laser is the trajectory walk-off, or lack of overlap of the photon and electron beams. Using pulsed wire magnet measurements and magnet shimming, we were able to control trajectory walk-off to less than +/-50 m m per field gain length. C1 Stanford Linear Accelerator Ctr, Menlo Pk, CA 94025 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Calif Los Angeles, Los Angeles, CA 90024 USA. RP Carr, R (reprint author), Stanford Linear Accelerator Ctr, 2575 Sand Hill Rd, Menlo Pk, CA 94025 USA. NR 13 TC 2 Z9 2 U1 1 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-4402 J9 PHYS REV SPEC TOP-AC JI Phys. Rev. Spec. Top.-Accel. Beams PD DEC PY 2001 VL 4 IS 12 AR 122402 DI 10.1103/PhysRevSTAB.4.122402 PN 2 PG 9 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 531VH UT WOS:000174437600005 ER PT J AU Danilov, V Henderson, S Holmes, J Burov, A AF Danilov, V Henderson, S Holmes, J Burov, A TI Closed orbit instability SO PHYSICAL REVIEW SPECIAL TOPICS-ACCELERATORS AND BEAMS LA English DT Article AB Because of a long-range resistive wake, the closed orbit may experience an unstable drift. Unlike the conventional betatron instabilities, this closed orbit instability is not sensitive to the spread of the betatron frequencies. For bunched beams, feedback appears to be the only way to stabilize the closed orbit above threshold. This new instability can be significant for both existing and designed high-intensity rings. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37830 USA. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. RP Danilov, V (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37830 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-4402 J9 PHYS REV SPEC TOP-AC JI Phys. Rev. Spec. Top.-Accel. Beams PD DEC PY 2001 VL 4 IS 12 AR 120101 DI 10.1103/PhysRevSTAB.4.120101 PN 2 PG 4 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 531VH UT WOS:000174437600001 ER PT J AU Carreras, BA Lynch, VE Zaslavsky, GM AF Carreras, BA Lynch, VE Zaslavsky, GM TI Anomalous diffusion and exit time distribution of particle tracers in plasma turbulence model SO PHYSICS OF PLASMAS LA English DT Article ID SELF-ORGANIZED CRITICALITY; TRANSPORT; SIMILARITY; AVALANCHES; PARADIGM; DYNAMICS AB To explore the character of transport in a plasma turbulence model with avalanche transport, the motion of tracer particles has been followed. Both the time evolution of the moments of the distribution function of the tracer particle radial positions, [parallel tor(t)-r(0)parallel to (n)], and their finite scale Lyapunov number are used to determine the anomalous diffusion exponent, nu. The numerical results show that the transport mechanism is superdiffusive with an exponent nu close to 0.88+/-0.07. The distribution of the exit times of particles trapped into stochastic jets is also determined. These particles have the lowest separation rate at the low resonant surfaces. (C) 2001 American Institute of Physics. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37830 USA. NYU, Courant Inst Math Sci, New York, NY 10012 USA. NYU, Dept Phys, New York, NY 10013 USA. RP Oak Ridge Natl Lab, Oak Ridge, TN 37830 USA. RI Lynch, Vickie/J-4647-2012 OI Lynch, Vickie/0000-0002-5836-7636 NR 29 TC 127 Z9 129 U1 0 U2 3 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 1070-664X EI 1089-7674 J9 PHYS PLASMAS JI Phys. Plasmas PD DEC PY 2001 VL 8 IS 12 BP 5096 EP 5103 DI 10.1063/1.1416180 PG 8 WC Physics, Fluids & Plasmas SC Physics GA 494YM UT WOS:000172313500006 ER PT J AU Porter, GD Casper, TA Moller, JM AF Porter, GD Casper, TA Moller, JM TI Edge localized mode particle losses from the DIII-D tokamak SO PHYSICS OF PLASMAS LA English DT Article ID DIVERTOR; ELMS; DISCHARGES; POWER AB Particle losses associated with edge localized mode (ELM) activity on the DIII-D tokamak [J. Luxon , Proceedings of the 11th International Conference on Plasma Physics and Controlled Nuclear Fusion (International Atomic Energy Agency, Vienna, 1986, Vol. I, p. 159] are evaluated quantitatively using density profile data obtained from a Thomson scattering system. It is shown that up to 10% of the total core particle content is lost with each ELM. The particle loss varies inversely with ELM frequency. The temporally averaged ELM particle loss is shown to be about 25% of the total particle loss from the confined region under a wide variety of plasma conditions. Although this ELM loss is a small fraction of the total ion flux, it is large compared to the particle input from neutral beam heating. Hence ELM particle losses are sufficient to control the density rise associated with H-mode plasma operation with neutral beam heating. In addition to controlling the average density by enhancing the total ion flow, albeit only by 25%, it is posited that the ELMs play a role in determining the density profile in the H-mode pedestal region. (C) 2001 American Institute of Physics. C1 Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Porter, GD (reprint author), Lawrence Livermore Natl Lab, L-637,POB 808, Livermore, CA 94551 USA. NR 16 TC 15 Z9 15 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD DEC PY 2001 VL 8 IS 12 BP 5140 EP 5150 DI 10.1063/1.1412863 PG 11 WC Physics, Fluids & Plasmas SC Physics GA 494YM UT WOS:000172313500011 ER PT J AU Campbell, EM Payne, SA Eden, JG AF Campbell, EM Payne, SA Eden, JG TI Howard Thomas Powell - Obituary SO PHYSICS TODAY LA English DT Biographical-Item C1 Gen Atom Co, San Diego, CA USA. Lawrence Livermore Natl Lab, Livermore, CA USA. Univ Illinois, Urbana, IL 61801 USA. RP Payne, SA (reprint author), Gen Atom Co, San Diego, CA USA. NR 0 TC 0 Z9 0 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 0031-9228 J9 PHYS TODAY JI Phys. Today PD DEC PY 2001 VL 54 IS 12 BP 76 EP 77 DI 10.1063/1.1445567 PG 2 WC Physics, Multidisciplinary SC Physics GA 497MD UT WOS:000172458700019 ER PT J AU Crease, RP AF Crease, RP TI Too confident about uncertainty SO PHYSICS WORLD LA English DT Editorial Material C1 SUNY Stony Brook, Dept Philosophy, Stony Brook, NY 11794 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. RP Crease, RP (reprint author), SUNY Stony Brook, Dept Philosophy, Stony Brook, NY 11794 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0953-8585 J9 PHYS WORLD JI Phys. World PD DEC PY 2001 VL 14 IS 12 BP 18 EP 18 PG 1 WC Physics, Multidisciplinary SC Physics GA 497NL UT WOS:000172462200018 ER PT J AU Sommardahl, C Cottrell, M Wilkinson, JE Woychik, RP Johnson, DK AF Sommardahl, C Cottrell, M Wilkinson, JE Woychik, RP Johnson, DK TI Phenotypic variations of orpk mutation and chromosomal localization of modifiers influencing kidney phenotype SO PHYSIOLOGICAL GENOMICS LA English DT Article DE polycystic kidney disease; biliary hyperplasia; pancreatic cysts ID GENETIC DISSECTION; COMPLEX TRAITS; MURINE MODEL; DISEASE; MOUSE; MICE; TGN737RPW; SEVERITY; LOCI AB The Oak Ridge polycystic kidney (orpk) mutant mouse model resulted from a transgene insertion into the Tg737 gene and exhibits a pleiotropic syndrome with lesions in the kidney, liver, and pancreas. We found marked differences in the phenotypic expression of the orpk mutation when bred on different genetic backgrounds. In the FVB/N background, the phenotype is very severe for kidney, pancreas, and liver lesions. To evaluate better how genetic background might influence the expressivity of the orpk phenotype, we bred the transgene into the C3HeB/ FeJLe (C3H) genetic background. We performed a genome- wide scan using backcross and intercross populations with more than 150 markers to map the chromosomal location of the modifier genes that differ in the FVB/N and C3H genetic backgrounds that affect the severity of kidney disease in the orpk mouse. Low- resolution interval mapping was performed using the Map Manager QTb program, with the interval explaining a significant portion of the variance being the distal end of chromosome 4. C1 Univ Tennessee, Coll Vet Med, Dept Large Anim Clin Sci, Knoxville, TN 37901 USA. Univ Tennessee, Coll Vet Med, Dept Pathol, Knoxville, TN 37901 USA. Lynx Therapeut, Hayward, CA 94545 USA. Oak Ridge Natl Lab, Div Life Sci, Oak Ridge, TN 37831 USA. RP Sommardahl, C (reprint author), UTCVM, Dept LACS, 2407 River Rd, Knoxville, TN 37996 USA. FU NIDDK NIH HHS [5-K08-DK-02466] NR 21 TC 12 Z9 13 U1 0 U2 1 PU AMER PHYSIOLOGICAL SOC PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 USA SN 1094-8341 J9 PHYSIOL GENOMICS JI Physiol. Genomics PD DEC PY 2001 VL 7 IS 2 BP 127 EP 134 PG 8 WC Cell Biology; Genetics & Heredity; Physiology SC Cell Biology; Genetics & Heredity; Physiology GA 505HE UT WOS:000172906700008 PM 11773599 ER PT J AU Gold, RE Solomon, SC McNutt, RL Santo, AG Abshire, JB Acuna, MH Afzal, RS Anderson, BJ Andrews, GB Bedini, PD Cain, J Cheng, AF Evans, LG Feldman, WC Follas, RB Gloeckler, G Goldsten, JO Hawkins, SE Izenberg, NR Jaskulek, SE Ketchum, EA Lankton, MR Lohr, DA Mauk, BH McClintock, WE Murchie, SL Schlemm, CE Smith, DE Starr, RD Zurbuchen, TH AF Gold, RE Solomon, SC McNutt, RL Santo, AG Abshire, JB Acuna, MH Afzal, RS Anderson, BJ Andrews, GB Bedini, PD Cain, J Cheng, AF Evans, LG Feldman, WC Follas, RB Gloeckler, G Goldsten, JO Hawkins, SE Izenberg, NR Jaskulek, SE Ketchum, EA Lankton, MR Lohr, DA Mauk, BH McClintock, WE Murchie, SL Schlemm, CE Smith, DE Starr, RD Zurbuchen, TH TI The MESSENGER mission to Mercury: scientific payload SO PLANETARY AND SPACE SCIENCE LA English DT Article ID GAMMA-RAY SPECTROMETER; ENERGETIC PARTICLES; SPACECRAFT; INSTRUMENT AB The MErcury, Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) mission will send the first spacecraft to orbit the planet Mercury. A miniaturized set of seven instruments, along with the spacecraft telecommunications system, provide the means of achieving the scientific objectives that motivate the mission. The payload includes a combined wide- and narrow-angle imaging system; gamma -ray, neutron, and X-ray spectrometers for remote geochemical sensing; a vector magnetometer; a laser altimeter; a combined ultraviolet-visible and visible-infrared spectrometer to detect atmospheric species and map mineralogical absorption features; and an energetic particle and plasma spectrometer to characterize ionized species in the magnetosphere. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Johns Hopkins Univ, Appl Phys Lab, Laurel, MD 20723 USA. Carnegie Inst Washington, Dept Terr Magnetism, Washington, DC 20015 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ Michigan, Dept Atmospher Ocean & Space Sci, Ann Arbor, MI 48109 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Maryland, Dept Phys, College Pk, MD 20742 USA. Univ Colorado, Atmospher & Space Phys Lab, Boulder, CO 80303 USA. RP Gold, RE (reprint author), Johns Hopkins Univ, Appl Phys Lab, Johns Hopkins Rd, Laurel, MD 20723 USA. RI Anderson, Brian/I-8615-2012; Abshire, James/I-2800-2013; McNutt, Ralph/E-8006-2010; Murchie, Scott/E-8030-2015; Izenberg, Noam/F-3952-2015; Mauk, Barry/E-8420-2017 OI McNutt, Ralph/0000-0002-4722-9166; Murchie, Scott/0000-0002-1616-8751; Izenberg, Noam/0000-0003-1629-6478; Mauk, Barry/0000-0001-9789-3797 NR 21 TC 86 Z9 87 U1 0 U2 5 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0032-0633 J9 PLANET SPACE SCI JI Planet Space Sci. PD DEC PY 2001 VL 49 IS 14-15 BP 1467 EP 1479 DI 10.1016/S0032-0633(01)00086-1 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 495VN UT WOS:000172361200006 ER PT J AU Takeuchi, Y Kubiske, ME Isebrands, JG Pregtizer, KS Hendrey, G Karnosky, DF AF Takeuchi, Y Kubiske, ME Isebrands, JG Pregtizer, KS Hendrey, G Karnosky, DF TI Photosynthesis, light and nitrogen relationships in a, young deciduous forest canopy under open-air CO2 enrichment SO PLANT CELL AND ENVIRONMENT LA English DT Article DE A/C; analysis; global change; N allocation; Rubisco; trembling aspen ID CONTRASTING SHADE TOLERANCE; RISING ATMOSPHERIC CO2; ELEVATED CO2; FAGUS-SYLVATICA; USE EFFICIENCY; LEAF NITROGEN; GAS-EXCHANGE; C-3 PLANTS; TREE; ACCLIMATION AB Leaf photosynthesis (Ps), nitrogen (N) and light environment were measured on Populus tremuloides trees in a developing canopy under free-air CO2 enrichment in Wisconsin, USA. After 2 years of growth, the trees averaged 1.5 and 1.6 in tall under ambient and elevated CO2, respectively, at the beginning of the study period in 1999. They grew to 2.6 and 2.9 in, respectively, by the end of the 1999 growing season. Daily integrated photon flux from cloud-free days (PPFDday,sat) around the lowermost branches was 16.8 +/- 0.8 and 8.7 +/- 0.2% of values at the top for the ambient and elevated CO2 canopies, respectively. Elevated CO2 significantly decreased leaf N on a mass, but not on an area, basis. N per unit leaf area was related linearly to PPFDday,sat throughout the canopies, and elevated CO2 did not affect that relationship. Leaf Ps light-response curves responded differently to elevated CO2, depending upon canopy position. Elevated CO2 increased Ps(sat) only in the upper (unshaded) canopy, whereas characteristics that would favour photosynthesis in shade were unaffected by elevated CO2. Consequently, estimated daily integrated Ps on cloud-free days (Ps(day,sat)) was stimulated by elevated CO2 only in the upper canopy. Ps(day,sat) of the lowermost branches was actually lower with elevated CO2 because of the darker light environment. The lack of CO2 stimulation at the mid- and lower canopy was probably related to significant down-regulation of photosynthetic capacity; there was no down-regulation of Ps in the upper canopy. The relationship between Ps(day,sat) and leaf N indicated that N was not optimally allocated within the canopy in a manner that would maximize whole-canopy Ps or photosynthetic N use efficiency. Elevated CO2 had no effect on the optimization of canopy N allocation. C1 Mississippi State Univ, Dept Forestry, Mississippi State, MS 39762 USA. US Forest Serv, USDA, NE Forest Expt Stn, Rhinelander, WI USA. Michigan Technol Univ, Sch Forestry & Wood Prod, Houghton, MI 49931 USA. Brookhaven Natl Lab, Brookhaven, NY USA. RP Kubiske, ME (reprint author), Mississippi State Univ, Dept Forestry, Box 9681, Mississippi State, MS 39762 USA. NR 47 TC 42 Z9 47 U1 0 U2 11 PU BLACKWELL SCIENCE LTD PI OXFORD PA P O BOX 88, OSNEY MEAD, OXFORD OX2 0NE, OXON, ENGLAND SN 0140-7791 J9 PLANT CELL ENVIRON JI Plant Cell Environ. PD DEC PY 2001 VL 24 IS 12 BP 1257 EP 1268 DI 10.1046/j.0016-8025.2001.00787.x PG 12 WC Plant Sciences SC Plant Sciences GA 501PD UT WOS:000172693200002 ER PT J AU Liu, YQ Dammann, C Bhattacharyya, MK AF Liu, YQ Dammann, C Bhattacharyya, MK TI The matrix metalloproteinase gene GmMMP2 is activated in response to pathogenic infections in soybean SO PLANT PHYSIOLOGY LA English DT Article ID PROGRAMMED CELL-DEATH; F-SP-GLYCINEA; PHYTOALEXIN SYNTHESIS; HOST-DEFENSE; MOLECULAR CHARACTERIZATION; HYPERSENSITIVE RESPONSE; FUSARIUM-SOLANI; FUNGAL ELICITOR; RESISTANCE; INDUCTION AB Matrix metalloproteinases (MMPs) play an important role in host defense responses against pathogens in mammals where their activities lead to the production of antimicrobial peptides. We have identified a novel soybean (Glycine max) metalloproteinase gene, GmMMP2, that is transcriptionally up-regulated in infected tissues, The deduced amino acid sequence indicates that this gene belongs to the MMP family. It is a preproprotein containing an N-terminal signal peptide, a cysteine switch, a zinc-binding catalytic motif, and a C-terminal transmembrane domain. The GmMMP2 expressed in and purified from Escherichia coli exhibited an in vitro enzymatic activity in digesting myelin basic protein. All plant metalloproteinases reported so far have no known functions. However, they have been suggested to be involved in extracellular cell matrix degradation during development or senescence. Our investigations demonstrate that the GmMMP2 transcript levels were rapidly increased in compatible and incompatible interactions of soybean tissues with the oomycete pathogen Phytophthora sojae or the bacterial pathogen Pseudomonas syringae pv. glycinea. In agreement with the GmMMP2 activation, a metalloproteinase activity was gradually increased in suspension-cultured cells following the bacterial infection. GmMMP2 was also activated in response to wounding and dehydration. However, GmMMP2 activation did not correlate with the oxidative burst leading to the hypersensitive response cell death or the tissue senescence progress that involves programmed cell death. Our investigations suggest that GmMMP2 may be involved in a novel defense response of soybean against pathogenic infections. C1 Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. Samuel Roberts Noble Fdn Inc, Div Plant Biol, Ardmore, OK 73402 USA. Scripps Res Inst, Dept Cell Biol, La Jolla, CA 92037 USA. Iowa State Univ, Dept Agron, Ames, IA 50011 USA. RP Liu, YQ (reprint author), Oak Ridge Natl Lab, Div Environm Sci, Bldg 1505,MS 6038, Oak Ridge, TN 37831 USA. NR 46 TC 41 Z9 45 U1 0 U2 2 PU AMER SOC PLANT BIOLOGISTS PI ROCKVILLE PA 15501 MONONA DRIVE, ROCKVILLE, MD 20855 USA SN 0032-0889 J9 PLANT PHYSIOL JI Plant Physiol. PD DEC PY 2001 VL 127 IS 4 BP 1788 EP 1797 DI 10.1104/pp.010593 PG 10 WC Plant Sciences SC Plant Sciences GA 503WK UT WOS:000172824500059 PM 11743122 ER PT J AU Escarguel, A Pegourie, B Hogan, J De Michelis, C Corre, Y Azeroual, A Ane, JM Guirlet, R Gunn, J Capes, H Godbert-Mouret, L Koubiti, M Stamm, R AF Escarguel, A Pegourie, B Hogan, J De Michelis, C Corre, Y Azeroual, A Ane, JM Guirlet, R Gunn, J Capes, H Godbert-Mouret, L Koubiti, M Stamm, R TI Atomic and molecular deuterium edge density evaluation from spectral analysis of the D alpha line shape SO PLASMA PHYSICS AND CONTROLLED FUSION LA English DT Article ID IONIZING PLASMA; HYDROGEN; IONIZATION; INTENSITIES; DIVERTOR; TOKAMAKS AB A method for molecular and atomic deuterium density evaluation, based on the analysis of the Dalpha spectral line shape coupled to a collisional radiative model, is presented. It is illustrated by its application to the plasma edge in the ergodic divertor configuration of the tokamak Tore Supra. An important molecular density (n(D2) > 10(18) m(-3), 1 cm radially away from the neutralizer plate), of the same order as the total atomic density n(D) (n(D)/n(D2) similar to 1.4), is found for the entire range of edge electron temperatures (10eV < T-e < 40eV). The density ratio of D atoms created by charge exchange or reflection of deuterons on the neutralizer plate and D atoms coming from D-2 dissociation is approximately constant for electron temperatures larger than 20eV (similar to0.9). A reasonable agreement is found with the results of the multi-one-dimensional code EDCOLL and the three-dimensional Monte Carlo code BBQ. The influence of the electron temperature and density distributions along the spectroscopic line of sight on the measurements is discussed in the frame of simulations with the numerical code EDCOLL. C1 CEA Cadarache, EURATOM Assoc, Dept Rech Fus Controlee, F-13108 St Paul Les Durance, France. Oak Ridge Natl Lab, Div Fus Energy, Oak Ridge, TN 37830 USA. Ctr St Jerome, UMR 6633 CNRS Aix Marseille 1, F-13397 Marseille, France. RP Escarguel, A (reprint author), CEA Cadarache, EURATOM Assoc, Dept Rech Fus Controlee, F-13108 St Paul Les Durance, France. NR 35 TC 10 Z9 10 U1 1 U2 3 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0741-3335 J9 PLASMA PHYS CONTR F JI Plasma Phys. Control. Fusion PD DEC PY 2001 VL 43 IS 12 BP 1733 EP 1746 DI 10.1088/0741-3335/43/12/307 PG 14 WC Physics, Fluids & Plasmas SC Physics GA 511QD UT WOS:000173276300007 ER PT J AU Petty, CC Baity, FW deGrassie, JS Mau, TK Pinsker, RI Porkolab, M Prater, R AF Petty, CC Baity, FW deGrassie, JS Mau, TK Pinsker, RI Porkolab, M Prater, R TI Fast wave current drive at high ion cyclotron harmonics on DIII-D SO PLASMA PHYSICS AND CONTROLLED FUSION LA English DT Article ID FUSION-TEST-REACTOR; D TOKAMAK; CURRENT PROFILE; PLASMAS; RANGE; FREQUENCIES; ABSORPTION; OPERATION; DESIGN AB Current driven by the fast Alfven wave is measured at the fourth and eighth harmonics of the deuterium ion cyclotron frequency in identical plasmas on the DIII-D tokamak. In non-sawtoothing discharges with neutral beam injection heating, the radial profile of the fast wave current drive (FWCD) is determined by the response of the loop voltage profile to co- and counter-antenna phasings. The dimensionless current drive efficiency is a factor of two greater for the eighth harmonic case compared to the fourth harmonic case. Modelling of the fast wave absorption using a ray tracing code shows that the decrease in FWCD efficiency for the latter situation can be explained by high harmonic damping of the fast waves on energetic ions. C1 Gen Atom Co, San Diego, CA 92186 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Univ Calif San Diego, La Jolla, CA 92093 USA. MIT, Cambridge, MA 02193 USA. RP Petty, CC (reprint author), Gen Atom Co, POB 85608, San Diego, CA 92186 USA. NR 38 TC 18 Z9 19 U1 0 U2 3 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0741-3335 J9 PLASMA PHYS CONTR F JI Plasma Phys. Control. Fusion PD DEC PY 2001 VL 43 IS 12 BP 1747 EP 1758 DI 10.1088/0741-3335/43/12/308 PG 12 WC Physics, Fluids & Plasmas SC Physics GA 511QD UT WOS:000173276300008 ER PT J AU Borghesi, M Schiavi, A Campbell, DH Haines, MG Willi, O MacKinnon, AJ Gizzi, LA Galimberti, M Clarke, RJ Ruhl, H AF Borghesi, M Schiavi, A Campbell, DH Haines, MG Willi, O MacKinnon, AJ Gizzi, LA Galimberti, M Clarke, RJ Ruhl, H TI Proton imaging: a diagnostic for inertial confinement fusion/fast ignitor studies SO PLASMA PHYSICS AND CONTROLLED FUSION LA English DT Article; Proceedings Paper CT 28th EPS Conference on Controlled Fusion and Plasma Physics CY JUN 18-22, 2001 CL FUNCHAL, PORTUGAL ID SOLID TARGETS; LASER; RADIOGRAPHY; BEAMS; ELECTRON; PLASMA AB Proton imaging is a recently proposed technique for diagnosis of dense plasmas, which favourably exploits the properties of protons produced by high-intensity laser-matter interaction. The technique allows the distribution of electric fields in plasmas and around laser-irradiated targets to be explored for the first time with high temporal and spatial resolution. This leads to the possibility of investigating as yet unexplored physical issues. In particular we will present measurements of transient electric fields in laser-plasmas and around laser-irradiated targets under various interaction conditions. Complex electric field structures have been observed in long-scale laser-produced plasmas, while global target charge-up and growth of electromagnetic instabilities have been detected following ultraintense interactions with solid targets. C1 Queens Univ Belfast, Dept Pure & Appl Phys, Belfast BT7 1NN, Antrim, North Ireland. Univ London Imperial Coll Sci & Technol, Blackett Lab, London SW7 2BZ, England. Lawrence Livermore Natl Lab, Livermore, CA USA. CNR, Area Ric, IFAM, Intense Laser Irradiat Lab, I-56100 Pisa, Italy. Rutherford Appleton Lab, Cent Laser Facil, Didcot OX11 0QX, Oxon, England. Rutherford Appleton Lab, Cent Laser Facil, D-12489 Berlin, Germany. Max Born Inst, D-12489 Berlin, Germany. RP Borghesi, M (reprint author), Queens Univ Belfast, Dept Pure & Appl Phys, Belfast BT7 1NN, Antrim, North Ireland. RI Gizzi, Leonida/F-4782-2011; Borghesi, Marco/K-2974-2012; MacKinnon, Andrew/P-7239-2014; Galimberti, Marco/J-8376-2016; Schiavi, Angelo/D-2924-2017 OI MacKinnon, Andrew/0000-0002-4380-2906; Galimberti, Marco/0000-0003-0661-7282; Schiavi, Angelo/0000-0002-7081-2747 NR 26 TC 96 Z9 103 U1 1 U2 11 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0741-3335 J9 PLASMA PHYS CONTR F JI Plasma Phys. Control. Fusion PD DEC PY 2001 VL 43 SU 12A BP A267 EP A276 PG 10 WC Physics, Fluids & Plasmas SC Physics GA 512UM UT WOS:000173342000022 ER PT J AU Doyle, EJ Baylor, LR Burrell, KH Casper, TA DeBoo, JC Ernst, DR Garofalo, AM Gohil, P Greenfield, CM Groebner, RJ Hyatt, AW Jackson, GL Jernigan, TC Kinsey, JE Lao, LL Lasnier, CJ Leboeuf, JN Makowski, M McKee, GR Moyer, RA Murakami, M Osborne, TH Peebles, WA Porkolab, M Porter, GD Rhodes, TL Rost, JC Rudakov, D Staebler, GM Stallard, BW Strait, J Sydora, RD Synakowski, EJ Wade, MR Wang, G Watkins, JG West, WP Zeng, L AF Doyle, EJ Baylor, LR Burrell, KH Casper, TA DeBoo, JC Ernst, DR Garofalo, AM Gohil, P Greenfield, CM Groebner, RJ Hyatt, AW Jackson, GL Jernigan, TC Kinsey, JE Lao, LL Lasnier, CJ Leboeuf, JN Makowski, M McKee, GR Moyer, RA Murakami, M Osborne, TH Peebles, WA Porkolab, M Porter, GD Rhodes, TL Rost, JC Rudakov, D Staebler, GM Stallard, BW Strait, J Sydora, RD Synakowski, EJ Wade, MR Wang, G Watkins, JG West, WP Zeng, L TI The quiescent double barrier regime in the DIII-D tokamak SO PLASMA PHYSICS AND CONTROLLED FUSION LA English DT Article; Proceedings Paper CT 28th EPS Conference on Controlled Fusion and Plasma Physics CY JUN 18-22, 2001 CL FUNCHAL, PORTUGAL ID MAGNETIC SHEAR DISCHARGES; HIGH-PERFORMANCE; TRANSPORT; CONFINEMENT; PLASMAS; SUSTAINMENT AB Experiments on the DIII-D tokamak have identified a new sustained high-performance operating mode, termed the quiescent double barrier (QDB) regime. The QDB regime combines internal transport barriers (ITBs) with a quiescent, edge localized mode (ELM)-free H-mode edge, termed QH-mode, giving rise to separate core and edge transport barriers. These double barriers have been maintained for >3.5 s (similar to25 tau(E)), demonstrating a long-pulse, quasisteady-state capability. The combination of core ITBs and edge H-mode temperature pedestals results in high-performance plasmas; a beta(N) H-89 product of 7 has been maintained for 10 tau(E), other peak (non-simultaneous) parameters include T-i less than or equal to 17 keV, beta(N) < 2.9% m TMA(-1), H-89 less than or equal to 2.6, beta less than or equal to 3.8%, tau(E) less than or equal to 160 ms, and DD neutron rate S-n less than or equal to 5,5 x 10(15) s(-1). These results address a major issue with tokamak plasmas: how to sustain long-pulse, high-performance H-mode plasmas without ELMs, yet retaining the density and impurity control hitherto provided by ELMs. In these QDB plasmas ELMs are replaced by continuous benign MHD activity in the edge, which enhances particle transport. A signature of operation with a QH-mode edge appears to be very large radial electric fields in the edge and scrape-off layer (SOL). In the core, simulations and modelling replicate many of the features of the observed transport and fluctuation behaviour, including the ion temperature profile and turbulence correlation lengths. Slow high-Z impurity accumulation (tau greater than or equal to 500 ms) is observed in the centre of many QDB plasmas, and is the subject of ongoing analysis. To date the QDB regime has only been obtained in plasmas with counter-NBI (injection anti-parallel to the plasma current), and with divertor cryopumping to control the density. C1 Univ Calif Los Angeles, Dept Elect Engn, Los Angeles, CA 90095 USA. Univ Calif Los Angeles, PSTI, Los Angeles, CA 90095 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. Univ Alberta, Edmonton, AB, Canada. MIT, Cambridge, MA 02139 USA. Univ Calif San Diego, San Diego, CA 92697 USA. Univ Wisconsin, Madison, WI 53706 USA. Univ Calif Los Angeles, Dept Phys, Los Angeles, CA 90095 USA. Lehigh Univ, Bethlehem, PA 18015 USA. Columbia Univ, New York, NY 10027 USA. Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Gen Atom Co, San Diego, CA 92186 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37381 USA. RP Doyle, EJ (reprint author), Univ Calif Los Angeles, Dept Elect Engn, Los Angeles, CA 90095 USA. RI Ernst, Darin/A-1487-2010 OI Ernst, Darin/0000-0002-9577-2809 NR 32 TC 22 Z9 22 U1 1 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0741-3335 J9 PLASMA PHYS CONTR F JI Plasma Phys. Control. Fusion PD DEC PY 2001 VL 43 SU 12A BP A95 EP A112 PG 18 WC Physics, Fluids & Plasmas SC Physics GA 512UM UT WOS:000173342000009 ER PT J AU Meyerhofer, DD Delettrez, JA Epstein, R Glebov, VY Goncharov, VN Keck, RL McCrory, RL McKenty, PW Marshall, FJ Radha, PB Regan, SP Roberts, S Seka, W Skupsky, S Smalyuk, VA Sorce, C Stoeckl, C Soures, JM Town, RPJ Yaakobi, B Frenje, JA Li, CK Petrasso, RD Seguin, FH Fletcher, K Padalino, S Freeman, C Izumi, N Lerche, RA Phillips, TW Sangster, TC AF Meyerhofer, DD Delettrez, JA Epstein, R Glebov, VY Goncharov, VN Keck, RL McCrory, RL McKenty, PW Marshall, FJ Radha, PB Regan, SP Roberts, S Seka, W Skupsky, S Smalyuk, VA Sorce, C Stoeckl, C Soures, JM Town, RPJ Yaakobi, B Frenje, JA Li, CK Petrasso, RD Seguin, FH Fletcher, K Padalino, S Freeman, C Izumi, N Lerche, RA Phillips, TW Sangster, TC TI Inferences of mix in direct-drive spherical implosions with high uniformity SO PLASMA PHYSICS AND CONTROLLED FUSION LA English DT Article; Proceedings Paper CT 28th EPS Conference on Controlled Fusion and Plasma Physics CY JUN 18-22, 2001 CL FUNCHAL, PORTUGAL ID INERTIAL CONFINEMENT FUSION; OMEGA-LASER SYSTEM; COMPRESSION; TARGETS AB A large number of diagnostics have been used to study the performance of gas-filled, plastic-shell direct-drive implosions on the 60-beam OMEGA laser system (Boehly T R et al 1997 Opt. Commun. 133 495). These diagnostics allow an estimate of the amount of fuel-pusher mixing in the compressed core. Implosions have primary neutron yields and fuel areal densities that are similar to35% and similar to100% of the predicted one-dimensional values, respectively. A highly constrained model of the core conditions and fuel-shell mix has been developed. It suggests that there is a 'clean' fuel region surrounded by a mixed region, with the clean region accounting for similar to70% of the fuel areal density. C1 Univ Rochester, Laser Energet Lab, Rochester, NY 14623 USA. MIT, Plasma Sci & Fus Ctr, Cambridge, MA 02139 USA. SUNY Coll Geneseo, Geneseo, NY 14454 USA. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Rochester, Dept Mech Engn, Rochester, NY 14627 USA. Univ Rochester, Dept Phys & Astron, Rochester, NY 14627 USA. RP Meyerhofer, DD (reprint author), Univ Rochester, Laser Energet Lab, 250 E River Rd, Rochester, NY 14623 USA. RI Goncharov, Valeri/H-4471-2011; IZUMI, Nobuhiko/J-8487-2016 OI IZUMI, Nobuhiko/0000-0003-1114-597X NR 29 TC 4 Z9 4 U1 0 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0741-3335 J9 PLASMA PHYS CONTR F JI Plasma Phys. Control. Fusion PD DEC PY 2001 VL 43 SU 12A BP A277 EP A286 DI 10.1088/0741-3335/43/12A/321 PG 10 WC Physics, Fluids & Plasmas SC Physics GA 512UM UT WOS:000173342000023 ER PT J AU Ongena, J Suttrop, W Becoulet, M Cordey, G Dumortier, P Eich, T Ingesson, LC Jachmich, S Lang, P Loarte, A Lomas, P Maddison, GP Messiaen, A Nave, MFF Rapp, J Saibene, G Sartori, R Sauter, O Strachan, JD Unterberg, B Valovic, M Alper, B Andrew, P Baranov, Y Brzozowski, J Bucalossi, J Brix, M Budny, R Charlet, M Coffey, I De Baar, M De Vries, P Gowers, C Hawkes, N von Hellermann, M Hillis, DL Hogan, J Jackson, GL Joffrin, E Jupen, C Kallenbach, A Koslowski, HR Lawson, KD Mantsinen, M Matthews, G Monier-Garbet, P McDonald, D Milani, F Murakami, M Murari, A Neu, R Parail, V Podda, S Puiatti, ME Righi, E Sartori, F Sarazin, Y Staebler, A Stamp, M Telesca, G Valisa, M Weyssow, B Zastrow, KD AF Ongena, J Suttrop, W Becoulet, M Cordey, G Dumortier, P Eich, T Ingesson, LC Jachmich, S Lang, P Loarte, A Lomas, P Maddison, GP Messiaen, A Nave, MFF Rapp, J Saibene, G Sartori, R Sauter, O Strachan, JD Unterberg, B Valovic, M Alper, B Andrew, P Baranov, Y Brzozowski, J Bucalossi, J Brix, M Budny, R Charlet, M Coffey, I De Baar, M De Vries, P Gowers, C Hawkes, N von Hellermann, M Hillis, DL Hogan, J Jackson, GL Joffrin, E Jupen, C Kallenbach, A Koslowski, HR Lawson, KD Mantsinen, M Matthews, G Monier-Garbet, P McDonald, D Milani, F Murakami, M Murari, A Neu, R Parail, V Podda, S Puiatti, ME Righi, E Sartori, F Sarazin, Y Staebler, A Stamp, M Telesca, G Valisa, M Weyssow, B Zastrow, KD CA EFDA-JET workprogramme contributor TI Recent progress on JET towards the ITER reference mode of operation at high density SO PLASMA PHYSICS AND CONTROLLED FUSION LA English DT Article; Proceedings Paper CT 28th EPS Conference on Controlled Fusion and Plasma Physics CY JUN 18-22, 2001 CL FUNCHAL, PORTUGAL ID ELMY H-MODES; ASDEX UPGRADE; PLASMA SHAPE; CONFINEMENT; TRIANGULARITY; PEDESTAL; DISCHARGES; TOKAMAKS; LIMIT AB Recent progress towards obtaining high density and high confinement in JET as required for the ITER reference scenario at Q = 10 is summarized. Plasmas with simultaneous confinement H-98(y.2) = 1 and densities up to n/n(Gw) similar to 1 are now routinely obtained. This has been possible (i) by using plasmas at high (delta similar to 0.5) and medium (delta similar to 0.3-0.4) triangularity with sufficient heating power to maintain Type I ELMs, (ii) with impurity seeded plasmas at high (delta similar to 0.5) and low (delta less than or equal to 0.2) triangularity, (iii) with an optimized pellet injection sequence, maintaining the energy confinement and raising the density, and (iv) by carefully tuning the gas puff rate leading to plasmas with peaked density profiles and good confinement at long time scales. These high performance discharges exhibit Type I ELMs, with a new and more favourable behaviour observed at high densities, requiring further studies. Techniques for a possible mitigation of these ELMs are discussed, and first promising results are obtained with impurity seeding in discharges at high triangularity. Scaling studies using the new data of this year show a strong dependence of confinement on upper triangularity, density and proximity to the Greenwald limit. Observed MHD instabilities and methods to avoid these in high density and high confinement plasmas are discussed. C1 EURATOM Assoc Belgian State, KMS, ERM, LPP, B-1000 Brussels, Belgium. EURATOM, Max Planck Inst Plasmaphys, D-85748 Garching, Germany. CEA Cadarache, F-13108 St Paul Les Durance, France. UKAEA Euratom Fus Assoc, Culham, England. Forschungszentrum Julich, Inst Plasmaphys, EURATOM Assoc, D-52425 Julich, Germany. EURATOM, FOM, Inst Plasmafys, NL-3430 BE Nieuwegein, Netherlands. EFDA, Close Support Unit, D-85748 Garching, Germany. EURATOM, IST, Ctr Fusao Nucl, P-1096 Lisbon, Portugal. Ecole Polytech Fed Lausanne, Assoc Euratom Confederat Suisse, Ctr Rech Phys Plasmas, CH-1007 Lausanne, Switzerland. Chalmers, EURATOM Assoc, NFR, S-41296 Gothenburg, Sweden. Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Natl Fus Facil, DIIID, San Diego, CA 92186 USA. EURATOM, ENEA Fusione, Ctr Ric Frascati, I-00044 Frascati, Rome, Italy. EURATOM, Enea Fusione, Consorzio RFX, I-35127 Padua, Italy. Free Univ Brussels, EURATOM Assoc, Belgian Stat Phys Theor & Math, Unite Phys Plasmas, B-1050 Brussels, Belgium. RI Nave, Maria/A-5581-2013; Lang, Peter/H-2507-2013; Neu, Rudolf /B-4438-2010 OI Nave, Maria/0000-0003-2078-6584; Lang, Peter/0000-0003-1586-8518; Neu, Rudolf /0000-0002-6062-1955 NR 38 TC 40 Z9 41 U1 0 U2 9 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0741-3335 EI 1361-6587 J9 PLASMA PHYS CONTR F JI Plasma Phys. Control. Fusion PD DEC PY 2001 VL 43 SU 12A BP A11 EP A30 DI 10.1088/0741-3335/43/12A/302 PG 20 WC Physics, Fluids & Plasmas SC Physics GA 512UM UT WOS:000173342000004 ER PT J AU Yamada, H Komori, A Ohyabu, N Kaneko, O Kawahata, K Watanabe, KY Sakakibara, S Murakami, S Ida, K Sakamoto, R Liang, Y Miyazawa, J Tanaka, K Narushima, Y Morita, S Masuzaki, S Morisaki, T Ashikawa, N Baylor, LR Cooper, WA Emoto, M Fisher, PW Funaba, H Goto, M Idei, H Ikeda, K Inagaki, S Inoue, N Isobe, M Khlopenkov, K Kobuchi, T Kostrioukov, A Kubo, S Kuroda, T Kumazawa, R Minami, T Muto, S Mutoh, T Nagayama, Y Nakajima, N Nakamura, Y Nakanishi, H Narihara, K Nishimura, K Noda, N Notake, T Ohdachi, S Oka, Y Osakabe, M Ozaki, T Peterson, BJ Rewoldt, G Sagara, A Saito, K Sasao, H Sasao, M Sato, K Sato, M Seki, T Sugama, H Shimozuma, T Shoji, M Suzuki, H Takeiri, Y Tamura, N Toi, K Tokuzawa, T Torii, Y Tsumori, K Watanabe, T Yamada, I Yamamoto, S Yokoyama, M Yoshimura, Y Watari, T Xu, Y Itoh, K Matsuoka, K Ohkubo, K Satow, T Sudo, S Uda, T Yamazaki, K Motojima, O Fujiwara, M AF Yamada, H Komori, A Ohyabu, N Kaneko, O Kawahata, K Watanabe, KY Sakakibara, S Murakami, S Ida, K Sakamoto, R Liang, Y Miyazawa, J Tanaka, K Narushima, Y Morita, S Masuzaki, S Morisaki, T Ashikawa, N Baylor, LR Cooper, WA Emoto, M Fisher, PW Funaba, H Goto, M Idei, H Ikeda, K Inagaki, S Inoue, N Isobe, M Khlopenkov, K Kobuchi, T Kostrioukov, A Kubo, S Kuroda, T Kumazawa, R Minami, T Muto, S Mutoh, T Nagayama, Y Nakajima, N Nakamura, Y Nakanishi, H Narihara, K Nishimura, K Noda, N Notake, T Ohdachi, S Oka, Y Osakabe, M Ozaki, T Peterson, BJ Rewoldt, G Sagara, A Saito, K Sasao, H Sasao, M Sato, K Sato, M Seki, T Sugama, H Shimozuma, T Shoji, M Suzuki, H Takeiri, Y Tamura, N Toi, K Tokuzawa, T Torii, Y Tsumori, K Watanabe, T Yamada, I Yamamoto, S Yokoyama, M Yoshimura, Y Watari, T Xu, Y Itoh, K Matsuoka, K Ohkubo, K Satow, T Sudo, S Uda, T Yamazaki, K Motojima, O Fujiwara, M TI Configuration flexibility and extended regimes in Large Helical Device SO PLASMA PHYSICS AND CONTROLLED FUSION LA English DT Article; Proceedings Paper CT 28th EPS Conference on Controlled Fusion and Plasma Physics CY JUN 18-22, 2001 CL FUNCHAL, PORTUGAL ID THERMAL TRANSPORT BARRIER; ENERGY CONFINEMENT; PLASMA-CONFINEMENT; LHD; INJECTION; SYSTEM; FIELD AB Recent experimental results in the Large Helical Device have indicated that a large pressure gradient can be formed beyond the stability criterion for the Mercier (high-n) mode. While the stability against an interchange mode is violated in the inward-shifted configuration due to an enhancement of the magnetic hill, the neoclassical transport and confinement of high-energy particle are, in contrast, improved by this inward shift. Mitigation of the unfavourable effects of MHD instability has led to a significant extension of the operational regime. Achievements of the stored energy of I MJ and the volume-averaged beta of 3% are representative results from this finding. A confinement enhancement factor above the international stellarator scaling ISS95 is also maintained around 1.5 towards a volume-averaged beta, (beta), of 3%. Configuration studies on confinement and MHD characteristics emphasize the superiority of the inward-shifted geometry to other geometries. The emergence of coherent modes appears to be consistent with the linear ideal MHD theory; however, the inward-shifted configuration has reduced heat transport in spite of a larger amplitude of magnetic fluctuation than the outward-shifted configuration. While neoclassical helical ripple transport becomes visible for the outward-shifted configuration in the collisionless regime, the inward-shifted configuration does not show any degradation of confinement deep in the collisionless regime (nu* < 0.1). The distinguished characteristics observed in the inward-shifted configuration help in creating a new perspective of MHD stability and related transport in net current-free plasmas. The first result of the pellet launching at different locations is also reported. C1 Natl Inst Fus Sci, Gifu 5295292, Japan. Grad Univ Adv Studies, Sch Math & Phys Sci, Dept Fus Sci, Yokohama, Kanagawa 2400193, Japan. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Ecole Polytech Fed Lausanne, Ctr Rech Phys Plasmas, CH-1015 Lausanne, Switzerland. Nagoya Univ, Dept Energy Engn & Sci, Nagoya, Aichi 4648603, Japan. Princeton Plasma Phys Lab, Princeton, NJ 08544 USA. RP Yamada, H (reprint author), Natl Inst Fus Sci, Gifu 5295292, Japan. RI Sakamoto, Ryuichi/E-7557-2013; Sakakibara, Satoru/E-7542-2013; Murakami, Sadayoshi/A-2191-2016; Ida, Katsumi/E-4731-2016 OI Sakamoto, Ryuichi/0000-0002-4453-953X; Sakakibara, Satoru/0000-0002-3306-0531; Murakami, Sadayoshi/0000-0002-2526-7137; Ida, Katsumi/0000-0002-0585-4561 NR 36 TC 72 Z9 72 U1 0 U2 5 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0741-3335 J9 PLASMA PHYS CONTR F JI Plasma Phys. Control. Fusion PD DEC PY 2001 VL 43 SU 12A BP A55 EP A71 DI 10.1088/0741-3335/43/12A/305 PG 17 WC Physics, Fluids & Plasmas SC Physics GA 512UM UT WOS:000173342000007 ER PT J AU Zarnstorff, MC Berry, LA Brooks, A Fredrickson, E Fu, GY Hirshman, S Hudson, S Ku, LP Lazarus, E Mikkelsen, D Monticello, D Neilson, GH Pomphrey, N Reiman, A Spong, D Strickler, D Boozer, A Cooper, WA Goldston, R Hatcher, R Isaev, M Kessel, C Lewandowski, J Lyon, JF Merkel, P Mynick, H Nelson, BE Nuehrenberg, C Redi, M Reiersen, W Rutherford, P Sanchez, R Schmidt, J White, RB AF Zarnstorff, MC Berry, LA Brooks, A Fredrickson, E Fu, GY Hirshman, S Hudson, S Ku, LP Lazarus, E Mikkelsen, D Monticello, D Neilson, GH Pomphrey, N Reiman, A Spong, D Strickler, D Boozer, A Cooper, WA Goldston, R Hatcher, R Isaev, M Kessel, C Lewandowski, J Lyon, JF Merkel, P Mynick, H Nelson, BE Nuehrenberg, C Redi, M Reiersen, W Rutherford, P Sanchez, R Schmidt, J White, RB TI Physics of the compact advanced stellarator NCSX SO PLASMA PHYSICS AND CONTROLLED FUSION LA English DT Article; Proceedings Paper CT 28th EPS Conference on Controlled Fusion and Plasma Physics CY JUN 18-22, 2001 CL FUNCHAL, PORTUGAL ID NEOCLASSICAL TRANSPORT; ASPECT-RATIO; ENERGY CONFINEMENT; HIGH-BETA; STABILITY; TOKAMAK; DESIGN; FIELD; COEFFICIENTS; EQUILIBRIA AB Compact optimized stellarators offer novel solutions for confining high-beta plasmas and developing magnetic confinement fusion. The three-dimensional plasma shape can be designed to enhance the magnetohydrodynamic (MHD) stability without feedback or nearby conducting structures and provide drift-orbit confinement similar to tokamaks. These configurations offer the possibility of combining the steady-state low-recirculating power, external control, and disruption resilience of previous stellarators with the low aspect ratio, high beta limit, and good confinement of advanced tokamaks. Quasi-axisymmetric equilibria have been developed for the proposed National Compact Stellarator Experiment (NCSX) with average aspect ratio 4-4.4 and average elongation similar to 1.8. Even with bootstrap-current consistent profiles, they are passively stable to the ballooning, kink, vertical, Mercier, and neoclassical-tearing modes for beta > 4%, without the need for external feedback or conducting walls. The bootstrap current generates only 1/4 of the magnetic rotational transform at beta = 4% (the rest is from the coils); thus the equilibrium is much less non-linear and is more controllable than similar advanced tokamaks. The enhanced stability is a result of 'reversed' global shear, the spatial distribution of local shear, and the large fraction of externally generated transform. Transport simulations show adequate fast-ion confinement and thermal neoclassical transport similar to equivalent tokamaks. Modular coils have been designed which reproduce the physics properties, provide good flux surfaces, and allow flexible variation of the plasma shape to control the predicted MHD stability and transport properties. C1 Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Columbia Univ, New York, NY 10027 USA. Ecole Polytech Fed Lausanne, Lausanne, Switzerland. Kurchatov Inst, Moscow, Russia. Max Planck Inst Plasma Phys, Greifswald, Germany. Univ Carlos III Madrid, Madrid, Spain. RP Zarnstorff, MC (reprint author), Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. RI Sanchez, Raul/C-2328-2008; pomphrey, neil/G-4405-2010; Spong, Donald/C-6887-2012; Hudson, Stuart/H-7186-2013; White, Roscoe/D-1773-2013; Isaev, Maxim/A-7910-2012 OI Spong, Donald/0000-0003-2370-1873; Hudson, Stuart/0000-0003-1530-2733; White, Roscoe/0000-0002-4239-2685; Isaev, Maxim/0000-0002-8492-0650 NR 46 TC 73 Z9 73 U1 2 U2 9 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0741-3335 J9 PLASMA PHYS CONTR F JI Plasma Phys. Control. Fusion PD DEC PY 2001 VL 43 SU 12A BP A237 EP A249 DI 10.1088/0741-3335/43/12A/318 PG 13 WC Physics, Fluids & Plasmas SC Physics GA 512UM UT WOS:000173342000020 ER PT J AU Salwinski, L Eisenberg, D AF Salwinski, L Eisenberg, D TI Motif-based fold assignment SO PROTEIN SCIENCE LA English DT Article DE bioinformatics; sequence motif; functional annotation; fold assignment ID PROTEIN-SEQUENCE DATABASE; 3-DIMENSIONAL STRUCTURE; GENOME ANALYSIS; PSI-BLAST; RECOGNITION; ANNOTATION; PREDICTION; PROFILES; SEARCH AB Conventional fold recognition techniques rely mainly on the analysis of the entire sequence of a protein. We present an MBA method to improve performance of any conventional sequence-based fold assignment. The method uses sequence motifs, such as those defined in the Prosite database, and the SwissProt annotation of the fold library. When combined with a simple SDP method, the coverage of MBA is comparable to the results obtained with PSI-BLAST. However, the set of the MBA predictions is significantly different from that of PSI-BLAST, leading to a 40% increase of the coverage for the combined MBA/PSI-BLAST method. The MBA approach can be easily adopted to include the results of sequence-independent function prediction methods and alternative motif and annotation databases. The method is available through the web server localized at http://www.doe-mbi.ucla.edu/mba. C1 Univ Calif Los Angeles, Dept Chem & Biochem, UCLA DOE Lab Struct Biol & Mol Med, Los Angeles, CA 90095 USA. Univ Calif Los Angeles, Dept Biol Chem, UCLA DOE Lab Struct Biol & Mol Med, Los Angeles, CA 90095 USA. RP Eisenberg, D (reprint author), Univ Calif Los Angeles, Dept Chem & Biochem, UCLA DOE Lab Struct Biol & Mol Med, Box 951570, Los Angeles, CA 90095 USA. EM david@mbi.ucla.edu NR 44 TC 10 Z9 10 U1 0 U2 0 PU COLD SPRING HARBOR LAB PRESS PI PLAINVIEW PA 1 BUNGTOWN RD, PLAINVIEW, NY 11724 USA SN 0961-8368 J9 PROTEIN SCI JI Protein Sci. PD DEC PY 2001 VL 10 IS 12 BP 2460 EP 2469 DI 10.1110/ps.ps.14401 PG 10 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 496UZ UT WOS:000172416600005 PM 11714913 ER PT J AU Persson, P Lunell, S Szoke, A Ziaja, B Hajdu, J AF Persson, P Lunell, S Szoke, A Ziaja, B Hajdu, J TI Shake-up and shake-off excitations with associated electron losses in X-ray studies of proteins SO PROTEIN SCIENCE LA English DT Article DE X-rays; photoionization; shake-up; shake-off; Auger emission; radiation damage; peptides; proteins ID SHELL IONIZED ATOMS; PHOTOELECTRON-SPECTROSCOPY; INTERMEDIATE NEGLECT; DIFFERENTIAL OVERLAP; SPECTRA; REORGANIZATION; DIFFRACTION; RADIATION; MOLECULES; TRIPLET AB Photo ionization of an atom by X-rays usually removes an inner shell electron from the atom, leaving behind a perturbed "hollow ion" whose relaxation may take different routes. In light elements, emission of an Auger electron is common. However, the energy and the total number of electrons released from the atom may be modulated by shake-up and shake-off effects. When the inner shell electron leaves, the outer shell electrons may find themselves in a state that is not an eigen-state of the atom in its surroundings. The resulting collective excitation is called shake-up. If this process also involves the release of low energy electrons from the outer shell, then the process is called shake-off. It is not clear how significant shake-up and shake-off contributions are to the overall ionization of biological materials like proteins. In particular, the interaction between the outgoing electron and the remaining system depends on the chemical environment of the atom, which can be studied by quantum chemical methods. Here we present calculations on model compounds to represent the most common chemical environments in proteins. The results show that the shake-up and shake-off processes affect similar to 20% of all emissions from nitrogen, 30% from carbon, 40% from oxygen, and 23% from sulfur. Triple and higher ionizations are rare for carbon, nitrogen, and oxygen, but are frequent for sulfur. The findings are relevant to the design of biological experiments at emerging X-ray free-electron lasers. C1 Univ Uppsala, Ctr Biomed, Dept Biochem, S-75123 Uppsala, Sweden. Univ Uppsala, Dept Quantum Chem, S-75120 Uppsala, Sweden. Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Inst Nucl Phys, Dept Theoret Phys, PL-31342 Krakow, Poland. Univ Uppsala, Dept High Energy Phys, S-75121 Uppsala, Sweden. RP Hajdu, J (reprint author), Univ Uppsala, Ctr Biomed, Dept Biochem, Box 576, S-75123 Uppsala, Sweden. RI Persson, Petter/B-5135-2016 OI Persson, Petter/0000-0001-7600-3230 NR 31 TC 19 Z9 19 U1 0 U2 5 PU COLD SPRING HARBOR LAB PRESS PI PLAINVIEW PA 1 BUNGTOWN RD, PLAINVIEW, NY 11724 USA SN 0961-8368 J9 PROTEIN SCI JI Protein Sci. PD DEC PY 2001 VL 10 IS 12 BP 2480 EP 2484 DI 10.1110/ps.ps.26201 PG 5 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 496UZ UT WOS:000172416600007 PM 11714915 ER PT J AU Lim, K Zhang, H Tempczyk, A Bonander, N Toedt, J Howard, A Eisenstein, E Herzberg, O AF Lim, K Zhang, H Tempczyk, A Bonander, N Toedt, J Howard, A Eisenstein, E Herzberg, O TI Crystal structure of YecO from Haemophilus influenzae (HI0319) reveals a methyltransferase fold and a bound S-adenosylhomocysteine SO PROTEINS-STRUCTURE FUNCTION AND BIOINFORMATICS LA English DT Article DE YecO; Haemophilus influenzae; EC2.1.1; methyltransferases; structural genomics ID N-METHYLTRANSFERASE; PROTEIN; MECHANISM; ADENOSYLMETHIONINE; CRYSTALLOGRAPHY; ALIGNMENT; SYSTEM AB The crystal structure of YecO from Haemophilus influenzae (HI0319), a protein annotated in the sequence databases as hypothetical, and that has not been assigned a function, has been determined at 2.2-Angstrom resolution. The structure reveals a fold typical of S-adenosyl-L-methionine-dependent (AdoMet) methyltransferase enzymes. Moreover, a processed cofactor, S-adenosyl-L-homo-cysteine (AdoHcy), is bound to the enzyme, further confirming the biochemical function of HI0319 and its sequence family members. An active site arginine, shielded from bulk solvent, interacts with an anion, possibly a chloride ion, which in turn interacts with the sulfur atom of AdoHcy. The AdoHcy and nearby protein residues delineate a small solvent-excluded substrate binding cavity of 162 Angstrom (3) in volume. The environment surrounding the cavity indicates that the substrate molecule contains a hydrophobic moiety and an anionic group. Many of the residues that define the cavity are invariant in the HI0319 sequence family but are not conserved in other methyltransferases. Therefore, the substrate specificity of YecO enzymes is unique and differs from the substrate specificity of all other methyltransferases sequenced to date. Examination of the Enzyme Commission list of methyltransferases prompted a manual inspection of 10 possible substrates using computer graphics and suggested that the ortho-substituted benzoic acids fit best in the active site. (C) 2001 Wiley-Liss, Inc. C1 Univ Maryland, Maryland Biotechnol Inst, Ctr Adv Res Biotechnol, Rockville, MD 20850 USA. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. IIT, Chicago, IL 60616 USA. RP Herzberg, O (reprint author), Univ Maryland, Maryland Biotechnol Inst, Ctr Adv Res Biotechnol, 9600 Gudelsky Dr, Rockville, MD 20850 USA. EM osnat@carb.nist.gov RI ID, IMCACAT/D-5867-2014 FU NCRR NIH HHS [1P41-RR12408-01A1]; NIGMS NIH HHS [P01 GM7890-1] NR 32 TC 27 Z9 28 U1 0 U2 1 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 0887-3585 J9 PROTEINS JI Proteins PD DEC 1 PY 2001 VL 45 IS 4 BP 397 EP 407 DI 10.1002/prot.10004 PG 11 WC Biochemistry & Molecular Biology; Biophysics SC Biochemistry & Molecular Biology; Biophysics GA 499KD UT WOS:000172569600012 PM 11746687 ER PT J AU Soares, TA Miller, JH Straatsma, TP AF Soares, TA Miller, JH Straatsma, TP TI Revisiting the structural flexibility of the complex p21(ras)-GTP: The catalytic conformation of the molecular switch II SO PROTEINS-STRUCTURE FUNCTION AND GENETICS LA English DT Article DE molecular dynamics; essential dynamics; nonlinear Poisson-Boltzmann signal transduction; molecular switches; catalytic mechanism ID H-RAS P21; FREE-ENERGY RELATIONSHIPS; ACTIVATING PROTEIN GAP; UNNATURAL AMINO-ACIDS; ESSENTIAL DYNAMICS; GTP HYDROLYSIS; 3-DIMENSIONAL STRUCTURES; SIGNAL-TRANSDUCTION; CRYSTAL-STRUCTURES; MECHANISM AB The hydrolysis of GTP in p21(ras) triggers conformational changes that regulate the ras/ERK signaling pathway. An important active site residue is Gln61, which has been found to be mutated in 30% of human tumors. The dynamics of the active site conformation is studied by using molecular dynamics simulation of two independent structures of the GTP-bound uncomplexed enzyme. Two distinct conformations of the enzyme are observed, in which the side-chain residue Gln61 is in different orientations. Essential dynamics analysis is used to describe the essential motions in the transition between the two conformations. Results are compared with earlier simulations of p21(ras) and its complex with GTPase activating protein p21-GAP. (C) 2001 Wiley-Liss, Inc. C1 Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Straatsma, TP (reprint author), Pacific NW Natl Lab, Environm Mol Sci Lab, 902 Battelle Blvd,POB 999, Richland, WA 99352 USA. RI Soares, Thereza/G-1065-2010 OI Soares, Thereza/0000-0002-5891-6906 NR 62 TC 9 Z9 9 U1 0 U2 2 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC, 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0887-3585 J9 PROTEINS JI Proteins PD DEC 1 PY 2001 VL 45 IS 4 BP 297 EP 312 DI 10.1002/prot.1150 PG 16 WC Biochemistry & Molecular Biology; Biophysics SC Biochemistry & Molecular Biology; Biophysics GA 499KD UT WOS:000172569600002 PM 11746677 ER PT J AU Mihalas, D AF Mihalas, D TI Fifty years of research on stellar atmospheres SO PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF AUSTRALIA LA English DT Article; Proceedings Paper CT Symposium on Some Highlights in Astronomy and Astrophysics CY SEP 30-OCT 01, 1999 CL CANBERRA, AUSTRALIA DE history & philosophy of astronomy ID LIGHT-ION SPECTRA; RADIATIVE-TRANSFER THEORY; QUADRATURE PERTURBATIONS; MODEL ATMOSPHERES; O-STARS AB I would like to begin by saying what a pleasure it is for me to be here. For my entire adult life I have wanted to come to Australia. Actually, I have been invited to visit here twice before, but each time I was thwarted by circumstances beyond my control. But this time I was determined to (a) prove that the third time is indeed the charm, and (b) pay homage to Walter Stibbs, who in my mind is the epitome of a scholar and a gentleman. I have known Walter as colleague, teacher, and friend, not to mention as art inspiration, both professional and personal. So I am here today to try to give some sense of progress in the study of stellar atmospheres, a field that Walter has graced with his virtuosic touch. I will follow an unabashedly personal path, describing the development as I experienced it. I will focus almost entirely on early-type stars, where we may reasonably expect the atmospheric layers to be homogeneous, and in radiative equilibrium. Only at the end will I mention our nearest stellar neighbor, the Sun, which, because we can study it in so much detail, offers counterexamples to almost all of the the theory that works so well for early-type stars. I offer apologies in advance to anyone this approach may offend. C1 Los Alamos Natl Lab, Appl Phys Div, Los Alamos, NM 87545 USA. RP Mihalas, D (reprint author), Los Alamos Natl Lab, Appl Phys Div, POB 1663, Los Alamos, NM 87545 USA. NR 16 TC 0 Z9 0 U1 0 U2 4 PU C S I R O PUBLISHING PI COLLINGWOOD PA 150 OXFORD ST, PO BOX 1139, COLLINGWOOD, VICTORIA 3066, AUSTRALIA SN 1323-3580 J9 PUBL ASTRON SOC AUST JI Publ. Astron. Soc. Aust. PD DEC PY 2001 VL 18 IS 3 BP 311 EP 316 DI 10.1071/AS01035 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 525DU UT WOS:000174054100010 ER PT J AU Milburn, GJ Ralph, T White, A Knill, E Laflamme, R AF Milburn, G. J. Ralph, T. White, A. Knill, E. Laflamme, R. TI EFFICIENT LINEAR OPTICS QUANTUM COPUTATION SO QUANTUM INFORMATION & COMPUTATION LA English DT Article AB Two qubit gates for photons are generally thought to require exotic materials with huge optical nonlinearities. We show here that, if we accept two qubit gates that only work conditionally, single photon sources, passive linear optics and particle detectors are sufficient for implementing reliable quantum algorithms. The conditional nature of the gates requires feed-forward from the detectors to the optical elements. Without feed forward, non-deterministic quantum computation is possible. We discuss one proposed single photon source based on the surface acoustic wave guiding of single electrons. C1 [Milburn, G. J.; Ralph, T.; White, A.] Univ Queensland, Ctr Quantum Comp Technol, St Lucia, Qld, Australia. [Knill, E.; Laflamme, R.] Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Milburn, GJ (reprint author), Univ Queensland, Ctr Quantum Comp Technol, St Lucia, Qld, Australia. NR 12 TC 1 Z9 1 U1 0 U2 0 PU RINTON PRESS, INC PI PARAMUS PA 565 EDMUND TERRACE, PARAMUS, NJ 07652 USA SN 1533-7146 J9 QUANTUM INF COMPUT JI Quantum Inform. Comput. PD DEC PY 2001 VL 1 SI SI BP 13 EP 19 PG 7 WC Computer Science, Theory & Methods; Physics, Particles & Fields; Physics, Mathematical SC Computer Science; Physics GA V31RX UT WOS:000208901800004 ER PT J AU Galeriu, D Crout, NMJ Melintescu, A Beresford, NA Peterson, SR Van Hees, M AF Galeriu, D Crout, NMJ Melintescu, A Beresford, NA Peterson, SR Van Hees, M TI A metabolic derivation of tritium transfer coefficients in animal products SO RADIATION AND ENVIRONMENTAL BIOPHYSICS LA English DT Article ID MILK AB Tritium is a potentially important environmental contaminant originating from the nuclear industry. and its behaviour in the environment is controlled by that of hydrogen. Animal food products represent a potentially important source of tritium in the human diet and a number of transfer coefficient values for tritium transfer to a limited number of animal products are available. In this paper we present an approach for the derivation of tritium transfer coefficients which is based on the metabolism of hydrogen in animals. The derived transfer coefficients separately account for transfer to and from free (i.e. water) and organically bound tritium. A novel aspect of the approach is that tritium transfer can be predicted for any animal product for which the required metabolic input parameters are available. The predicted transfer coefficients are compared to available independent data. Agreement is good (R-2=0.97) with the exception of the transfer coefficient for transfer from tritiated water to organically bound tritium in ruminants. This may be attributable to the particular characteristics of ruminant digestion. We show that tritium transfer coefficients will vary in response to the metabolic status of an animal (e.,a,. stage of lactation, diet digestibility etc.) and that the use of a single transfer coefficient from diet to animal product is inappropriate. It is possible to derive concentration ratio values from the estimated transfer coefficients which relate the concentration of tritiated water and organically bound tritium in an animal product to their respective concentrations in the animals diet. These concentration ratios are shown to be less subject to metabolic variation and may be more useful radioecological parameters than transfer coefficients. For tritiated water the concentration ratio shows little variation between animal products ranging from 0.59 to 0,82. In the case of organically bound tritium the concentration ratios vary between animal products from 0.15 (goat milk) to 0.67 (eggs). C1 Univ Nottingham, Sch Life & Environm Sci, Nottingham NG7 2RD, England. Natl Inst Phys & Nucl Engn, Bucharest 76900, Romania. Ctr Ecol & Hydrol, Merlewood Res Stn, Grange Over Sands LA11 6JU, Cumbria, England. Lawrence Livermore Natl Lab, Terr Atmospher Monitoring & Modeling Grp, Operat & Regulatory Affairs Div, Environm Protect Dept, Livermore, CA 94551 USA. CEN SCK, Radiat Protect, Radioecol, B-2400 Mol, Belgium. RP Crout, NMJ (reprint author), Univ Nottingham, Sch Life & Environm Sci, Nottingham NG7 2RD, England. RI Galeriu, Dan/B-7113-2011; Melintescu, Anca /F-5850-2011; Melintescu, Anca/D-7280-2016; Crout, Neil /A-1369-2011; Beresford, Nicholas/I-6188-2012 OI Melintescu, Anca /0000-0001-7468-3439; Melintescu, Anca/0000-0001-8406-6426; NR 37 TC 12 Z9 12 U1 0 U2 5 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0301-634X J9 RADIAT ENVIRON BIOPH JI Radiat. Environ. Biophys. PD DEC PY 2001 VL 40 IS 4 BP 325 EP 334 DI 10.1007/s00411-001-0116-5 PG 10 WC Biology; Biophysics; Environmental Sciences; Radiology, Nuclear Medicine & Medical Imaging SC Life Sciences & Biomedicine - Other Topics; Biophysics; Environmental Sciences & Ecology; Radiology, Nuclear Medicine & Medical Imaging GA 510GL UT WOS:000173200300010 PM 11820742 ER PT J AU Jenkins, RA Finn, D Tomkins, BA Maskarinec, MP AF Jenkins, RA Finn, D Tomkins, BA Maskarinec, MP TI Environmental tobacco smoke in the nonsmoking section of a restaurant: A case study SO REGULATORY TOXICOLOGY AND PHARMACOLOGY LA English DT Article ID OCCUPATIONAL EXPOSURE; INDOOR ENVIRONMENTS; AIR AB This study tested the concentrations of environmental tobacco smoke (ETS) components in a small restaurant/pub with smoking and nonsmoking areas- a facility outfitted with a heat-recovery ventilation system and directional airflow. The ETS levels in the nonsmoking area were compared with those in other similar restaurants/pubs where indoor smoking is altogether prohibited. The results indicate that ETS component concentrations in the nonsmoking section of the facility in question were not statistically different (P < 0.05) from those measured in similar facilities where smoking is prohibited. The regulatory implications of these findings are that ventilation techniques for restaurants/pubs with separate smoking and nonsmoking areas are capable of achieving nonsmoking area ETS concentrations that are comparable to those of similar facilities that prohibit smoking outright. (C) 2001 Elsevier Science. C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. Synchron Projects Inc, Finn Projects, Toronto, ON, Canada. RP Jenkins, RA (reprint author), Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. OI Tomkins, Bruce/0000-0001-8520-1415 NR 14 TC 10 Z9 11 U1 1 U2 3 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0273-2300 J9 REGUL TOXICOL PHARM JI Regul. Toxicol. Pharmacol. PD DEC PY 2001 VL 34 IS 3 BP 213 EP 220 DI 10.1006/rtph.2001.1499 PG 8 WC Medicine, Legal; Pharmacology & Pharmacy; Toxicology SC Legal Medicine; Pharmacology & Pharmacy; Toxicology GA 511HY UT WOS:000173259600002 PM 11754526 ER PT J AU Goverse, T Hekkert, MP Groenewegen, P Worrell, E Smits, REHM AF Goverse, T Hekkert, MP Groenewegen, P Worrell, E Smits, REHM TI Wood innovation in the residential construction sector; opportunities and constraints SO RESOURCES CONSERVATION AND RECYCLING LA English DT Article DE wood use; construction sector; innovation characteristics; innovation systems; material management; environmental policy; CO2 emission reduction; cluster program AB We study the opportunities to increase the use of wood in the Dutch residential construction sector and assess the effects on material related CO2 emission. Four house types are modeled with increasing quantities of wood used in constructions. CO2 emission reductions of almost 50% are technically possible. We assess the innovation characteristics of these wood applications to create insights in the complexity of the necessary change process. Then we relate the innovation characteristics of the wood options to the context in which implementation of the technologies take place. The options vary strongly in the required technical and network changes and so do the opportunities to implement them. Based on this we expect that a 12% CO2 emission reduction related to material use for residential buildings is possible in the short term by an increased share of wood use. We also study the possibilities for increased wood recycling practices. A large technical potential exists. To achieve this potential a significant policy effort is needed since significant changes in both technical and network dimensions are necessary. To stimulate innovation in the use of wood in residential construction, important focus points of policy making should be the culture in the Dutch construction sector, the way new building projects are commissioned, research areas within the building sector, and stabilization of building networks. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Utrecht, Dept Innovat Studies, NL-3524 CS Utrecht, Netherlands. UN Environm Program, Nairobi, Kenya. Vrije Univ Amsterdam, Fac Social Cultural Sci, Dept Publ Adm & Commun Sci DBL859, NL-1081 HV Amsterdam, Netherlands. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Hekkert, MP (reprint author), Univ Utrecht, Dept Innovat Studies, Heidelberglaan 8, NL-3524 CS Utrecht, Netherlands. RI Hekkert, Marko/F-2528-2012; Worrell, Ernst/L-5455-2013; Groenewegen, Peter/B-1959-2012 OI Hekkert, Marko/0000-0003-0570-5117; Worrell, Ernst/0000-0002-0199-9755; Groenewegen, Peter/0000-0003-4006-1601 NR 48 TC 37 Z9 37 U1 1 U2 10 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-3449 J9 RESOUR CONSERV RECY JI Resour. Conserv. Recycl. PD DEC PY 2001 VL 34 IS 1 BP 53 EP 74 DI 10.1016/S0921-3449(01)00093-3 PG 22 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 490PZ UT WOS:000172061400005 ER PT J AU Michaelian, KH Jackson, RS Homes, CC AF Michaelian, KH Jackson, RS Homes, CC TI Synchrotron infrared photoacoustic spectroscopy SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article ID LIGHT-SOURCE; BEAMLINE AB The use of synchrotron radiation (SR) as a far- and mid-infrared source in the measurement of photoacoustic Fourier transform infrared spectra of solids is demonstrated for the first time in this work. Initial experiments were performed at beamline U10A at the National Synchrotron Light Source, Brookhaven National Laboratory. For synchrotron photoacoustic spectroscopy to be feasible, it must yield results superior to those obtained with a conventional thermal (Globar(R)) source; accordingly, SR and Globar(R) photoacoustic spectra recorded under similar conditions were compared in detail. The intensities of SR far-infrared photoacoustic spectra were found to be consistently greater than the corresponding Globar(R) spectra. At shorter wavelengths, SR always underfills the effective aperture (or, alternately, sample size); SR is a superior source in a spectral region that is a function of this aperture. The high wave number limit of this region exhibits a power-law dependence on aperture size. This investigation also showed that the entire mid-infrared photoacoustic spectrum is more intense using SR and apertures smaller than approximately 0.5 mm. (C) 2001 American Institute of Physics. C1 Nat Resources Canada, CANMET Western Res Ctr, Devon, AB T9G 1A8, Canada. Bruker Opt Inc, Billerica, MA 01821 USA. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Michaelian, KH (reprint author), Nat Resources Canada, CANMET Western Res Ctr, 1 Oil Patch Dr, Devon, AB T9G 1A8, Canada. EM michaeli@nrcan.gc.ca NR 13 TC 3 Z9 3 U1 0 U2 4 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD DEC PY 2001 VL 72 IS 12 BP 4331 EP 4336 DI 10.1063/1.1416107 PG 6 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 496GG UT WOS:000172387400001 ER PT J AU Garcia, E Back, BB Baker, MD Barton, DS Basilev, S Bates, BD Baum, R Betts, RR Bialas, A Bindel, R Bogucki, W Budzanowski, A Busza, W Carroll, A Ceglia, M Chang, YH Chen, AE Coghen, T Conner, C Czyz, W Dabrowski, B Decowski, MP Despet, M Fita, P Fitch, J Friedl, M Galuszka, K Ganz, R George, N Godlewski, J Gomes, C Griesmayer, E Gulbrandsen, K Gushue, S Halik, J Halliwel, C Haridas, P Hayes, A Heintzelman, GA Henderson, C Hollis, R Holynski, R Holzman, B Johnson, E Kane, J Katzy, J Kita, W Kotula, J Kraner, H Kucewicz, W Kulinich, P Law, C Lemler, M Ligocki, J Lin, W Manly, S McLeod, D Michalowski, J Mignerey, A Mulmenstadt, J Neal, M Nouicer, R Olszewski, A Pak, R Park, IC Patel, M Pernegger, H Plesko, M Reed, C Remsberg, LP Reuter, M Roland, C Roland, G Ross, D Rosenberg, L Ryan, J Sanzgiri, A Sarin, P Sawicki, P Scaduto, J Shea, J Sinacore, J Skulski, W Steadman, SG Stephans, GSF Steinberg, P Straczek, A Stodulski, M Strek, M Stopa, Z Sukhanov, A Surowiecka, K Tang, JL Teng, R Trzupek, A Vale, CM van Nieuwenhuizen, GJ Verdier, R Wadsworth, B Wolfs, FLH Wosiek, B Wozniak, K Wuosmaa, AH Wyslouch, B Zalewski, K Zychowski, P AF Garcia, E Back, BB Baker, MD Barton, DS Basilev, S Bates, BD Baum, R Betts, RR Bialas, A Bindel, R Bogucki, W Budzanowski, A Busza, W Carroll, A Ceglia, M Chang, YH Chen, AE Coghen, T Conner, C Czyz, W Dabrowski, B Decowski, MP Despet, M Fita, P Fitch, J Friedl, M Galuszka, K Ganz, R George, N Godlewski, J Gomes, C Griesmayer, E Gulbrandsen, K Gushue, S Halik, J Halliwel, C Haridas, P Hayes, A Heintzelman, GA Henderson, C Hollis, R Holynski, R Holzman, B Johnson, E Kane, J Katzy, J Kita, W Kotula, J Kraner, H Kucewicz, W Kulinich, P Law, C Lemler, M Ligocki, J Lin, W Manly, S McLeod, D Michalowski, J Mignerey, A Mulmenstadt, J Neal, M Nouicer, R Olszewski, A Pak, R Park, IC Patel, M Pernegger, H Plesko, M Reed, C Remsberg, LP Reuter, M Roland, C Roland, G Ross, D Rosenberg, L Ryan, J Sanzgiri, A Sarin, P Sawicki, P Scaduto, J Shea, J Sinacore, J Skulski, W Steadman, SG Stephans, GSF Steinberg, P Straczek, A Stodulski, M Strek, M Stopa, Z Sukhanov, A Surowiecka, K Tang, JL Teng, R Trzupek, A Vale, CM van Nieuwenhuizen, GJ Verdier, R Wadsworth, B Wolfs, FLH Wosiek, B Wozniak, K Wuosmaa, AH Wyslouch, B Zalewski, K Zychowski, P CA PHOBOS collaboration TI Phobos at RHIC 2000 SO REVISTA MEXICANA DE FISICA LA English DT Article; Proceedings Paper CT 24th Symposium on Nuclear Physics CY JAN 03-06, 2001 CL TAXCO, MEXICO SP Soc Mexicana Fis, Div Fis, UNAM, Inst Ciencias Nucl, Cent Latinoamer Fis DE relativistic heavy ion collisions ID NUCLEUS-NUCLEUS COLLISIONS; DISTRIBUTIONS; MULTIPLICITY; ENERGIES AB The relativistic heavy ion collider (RHIC) at Brookhaven national laboratory delivered in June 2000 the first collisions between Au nuclei at the highest center-of-mass energies achieved in a controlled enviroment to date, PHOBOS is one of the four experiments installed during this phase of RHIC running. This paper will describe the PHOBOS experiment, and discuss the results of the first physics measurement, the pseudo rapidity densities of primary charged particles near mid rapidity in central Au+Au collisions at two different energies, roots(NN) = 56 and 130 GeV. The observed densities are higher than those previously observed in any collisions, and the rate of increase between the two energies is larger than that for nucleon-nucleon collisions at comparable beam energies. This talk will describe the PHOBOS experiment, discuss the first physics measurement, and conclude with the present status of the experiment, the physics analysis and the perspectives for the future. C1 Argonne Natl Lab, Argonne, IL 60439 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. Inst Nucl Phys, Krakow, Poland. Jagiellonian Univ, Krakow, Poland. MIT, Cambridge, MA 02139 USA. Natl Cent Univ, Chungli 32054, Taiwan. Univ Illinois, Chicago, IL USA. Univ Rochester, Rochester, NY 14627 USA. Yale Univ, New Haven, CT 06520 USA. RP Garcia, E (reprint author), Univ Maryland, College Pk, MD 20742 USA. RI Decowski, Patrick/A-4341-2011; Mignerey, Alice/D-6623-2011; Muelmenstaedt, Johannes/K-2432-2015 OI Muelmenstaedt, Johannes/0000-0003-1105-6678 NR 12 TC 0 Z9 0 U1 0 U2 0 PU SOCIEDAD MEXICANA DE FISICA PI COYOACAN PA APARTADO POSTAL 70-348, COYOACAN 04511, MEXICO SN 0035-001X J9 REV MEX FIS JI Rev. Mex. Fis. PD DEC PY 2001 VL 47 SU 2 BP 98 EP 103 PG 6 WC Physics, Multidisciplinary SC Physics GA 508DJ UT WOS:000173072600018 ER PT J AU Kempton, W Holland, DC Bunting-Howarth, K Hannan, E Payne, C AF Kempton, W Holland, DC Bunting-Howarth, K Hannan, E Payne, C TI Local environmental groups: A systematic enumeration in two geographical areas SO RURAL SOCIOLOGY LA English DT Article AB Local environmental groups, although acknowledged increasingly since the mid-1980s, have not been sampled Systematically, have been reported to consist of only a few types, and are often considered to be of only minor political significance. In this study we systematically inventoried all local environmental groups in two U.S. geographical areas: the Delmarva Peninsula and the state of North Carolina. We found 566 local groups, seven to 20 times the number reported in the best published directory. Three-quarters did not fit the types most commonly characterized in the literature. Extrapolating from our study areas, we estimate that 16,000 to 30,000 local environmental groups are active in the United States. We find that these groups have a subset of "core" members, those active in organizing and local operations. We estimate the population of core members at 265,000 to 290,000, over 50 times the total of professional staff members of all U.S. national environmental organizations. These groups affect local and state environmental policy, enforcement of environmental laws, the shaping of environmental issues, and the social infrastructure for environmental behaviors. C1 Univ Delaware, Coll Marine Studies, Newark, DE 19716 USA. Univ N Carolina, Chapel Hill, NC USA. Univ Delaware, Newark, DE 19716 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Kempton, W (reprint author), Univ Delaware, Coll Marine Studies, Newark, DE 19716 USA. RI Kempton, Willett/H-5176-2012 OI Kempton, Willett/0000-0002-7284-8954 NR 36 TC 29 Z9 29 U1 0 U2 1 PU RURAL SOCIOLOGICAL SOC PI BELLINGHAM PA C/O RABEL J BURDGE, TREASURER, WESTERN WASHINGTON UNIV, DEPT SOCIOL ARNTZEN HALL R-510, BELLINGHAM, WA 98225-9081 USA SN 0036-0112 J9 RURAL SOCIOL JI Rural Sociol. PD DEC PY 2001 VL 66 IS 4 BP 557 EP 578 PG 22 WC Sociology SC Sociology GA 501GB UT WOS:000172676000004 ER PT J AU Borchelt, RE AF Borchelt, RE TI Communicating the future - Report of the research roadmap panel for public communication of science and technology in the twenty-first century SO SCIENCE COMMUNICATION LA English DT Article ID MEDIA AB This article reports the principal findings and recommendations of the Research Roadmap Panel for Public Communication of Science and Technology in the Twenty-first Century. Beginning in 1998, the Space Sciences Laboratory at NASA's George C. Marshall Space Flight Center chartered a fifteen-member working group to develop a research strategy that would address the big questions in science communication academic research and identify the best practices in science and technology communication as they are being implemented in research institutions across the United States and abroad. The working group met eight times at various U.S. research institutions, invited science communicators and others to meet with them, and solicited public and other comment in preparation for this article. C1 US DOE, Off Sci SC5, Washington, DC 20585 USA. RP Borchelt, RE (reprint author), US DOE, Off Sci SC5, 1000 Independence Ave SW, Washington, DC 20585 USA. NR 19 TC 10 Z9 10 U1 2 U2 24 PU SAGE PUBLICATIONS INC PI THOUSAND OAKS PA 2455 TELLER RD, THOUSAND OAKS, CA 91320 USA SN 1075-5470 J9 SCI COMMUN JI Sci. Commun. PD DEC PY 2001 VL 23 IS 2 BP 194 EP 211 DI 10.1177/1075547001023002006 PG 18 WC Communication SC Communication GA 494ZT UT WOS:000172316300006 ER PT J AU Polikar, R Shinar, R Udpa, L Porter, MD AF Polikar, R Shinar, R Udpa, L Porter, MD TI Artificial intelligence methods for selection of an optimized sensor array for identification of volatile organic compounds SO SENSORS AND ACTUATORS B-CHEMICAL LA English DT Article DE optimum coating selection; decision tree; wrapper search; neural network classification ID ACOUSTIC-WAVE SENSORS; PATTERN-RECOGNITION; VAPOR RECOGNITION; CLUSTER-ANALYSIS; MIXTURES; CLASSIFICATION; RESPONSES; DESIGN AB We have investigated two artificial intelligence (Al)-based approaches for the optimum selection of a sensor array for the identification of volatile organic compounds (VOCs). The array consists of quartz crystal microbalances (QCMs), each coated with a different polymeric material. The first approach uses a decision tree classification algorithm to determine the minimum number of features that are required to classify the training data correctly. The second approach employs the hill-climb search algorithm to search the feature space for the optimal minimum feature set that maximizes the performance of a neural network classifier. We also examined the value of simple statistical procedures that could be integrated into the search algorithm in order to reduce computation time. The strengths and limitations of each approach are discussed. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Rowan Univ, Dept Elect & Comp Engn, Glassboro, NJ 08028 USA. Iowa State Univ Sci & Technol, Ames Lab, US DOE, Microanalyt Instrument Ctr, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Dept Chem, Microanalyt Instrument Ctr, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Dept Elect & Comp Engn, Ames, IA 50011 USA. RP Polikar, R (reprint author), Rowan Univ, Dept Elect & Comp Engn, 136 Rowan Hall, Glassboro, NJ 08028 USA. RI Polikar, Robi/N-4742-2015 OI Polikar, Robi/0000-0002-2739-4228 NR 46 TC 36 Z9 38 U1 0 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 1 PY 2001 VL 80 IS 3 BP 243 EP 254 DI 10.1016/S0925-4005(01)00903-0 PG 12 WC Chemistry, Analytical; Electrochemistry; Instruments & Instrumentation SC Chemistry; Electrochemistry; Instruments & Instrumentation GA 492PY UT WOS:000172177800013 ER PT J AU Cubbins, LA Szaflarski, M AF Cubbins, LA Szaflarski, M TI Family effects on self-reported health among Russian wives and husbands SO SOCIAL SCIENCE & MEDICINE LA English DT Article; Proceedings Paper CT Annual Meeting of the American-Sociological-Association CY AUG 11-16, 2000 CL WASHINGTON, D.C. SP Amer Sociol Assoc DE Russia; self-reported health; husband/wife health; household labour; social transition ID MULTIPLE ROLES; LIFE EXPECTANCY; EASTERN-EUROPE; RATED HEALTH; MORTALITY; WOMEN; MEN; PERSPECTIVE; EDUCATION; HELSINKI AB Alcohol abuse and a transition to the market economy are often blamed for high mortality and low life expectancy in Russia, but little is known about proximate influences on individual health. This study estimates family influences on the self-reported health of Russian wives and husbands. Predicting gender differences in the determinants of health status, hypotheses are presented for the effects on spouses' self-reported health of five family characteristics: economic status, household division of labor, family decision-making, presence of young children. and housing conditions. Controls are included for age, education, sensitivity, alcohol use, job-related time. and urban-rural location. Data from a 1996 sample of couples (n = 925) from Moscow and two rural regions of Russia are analyzed using logistic regression. The findings provide mixed support for the hypotheses, though they do show the important role of family characteristics on spouses' health. Family economic standing is important to both spouses' self-reported health. though young children in the home is not. Family decision-making does influence spouses' health: when Russian wives are the primary decision makers in the family. their own health suffers, though their husbands' health is better. And support is found for the combined effects of job-related time and household labor but only for wives' health. When wife's household labor is low, the probability of her having poor health increases, the more time she devotes to her job. However, when she does substantially more domestic labor than her husband, her job-related time has the opposite effect, reducing the chances of poor health, the more time she spends on job activities. This study is important both in helping to account for poor health of Russians during the current economic and social transition and in identifying aspects of family life that affect men's and women's health cross-nationally. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Battelle Seattle Res Ctr, Ctr Publ Hlth Res, Seattle, WA 98105 USA. Univ Cincinnati, Dept Sociol, Cincinnati, OH 45221 USA. RP Cubbins, LA (reprint author), Battelle Seattle Res Ctr, Ctr Publ Hlth Res, 4500 Sand Point Way NE,Suite 100, Seattle, WA 98105 USA. OI Szaflarski, Magdalena/0000-0002-6228-1405 NR 51 TC 9 Z9 10 U1 0 U2 2 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0277-9536 J9 SOC SCI MED JI Soc. Sci. Med. PD DEC PY 2001 VL 53 IS 12 BP 1653 EP 1666 DI 10.1016/S0277-9536(00)00450-0 PG 14 WC Public, Environmental & Occupational Health; Social Sciences, Biomedical SC Public, Environmental & Occupational Health; Biomedical Social Sciences GA 497DK UT WOS:000172437300009 PM 11762891 ER PT J AU Smith, CW Ness, NF Burlaga, LF Skoug, RM McComas, DJ Zurbuchen, TH Gloeckler, G Haggerty, DK Gold, RE Desai, MI Mason, GM Mazur, JE Dwyer, JR Popecki, MA Mobius, E Cohen, CMS Leske, RA AF Smith, CW Ness, NF Burlaga, LF Skoug, RM McComas, DJ Zurbuchen, TH Gloeckler, G Haggerty, DK Gold, RE Desai, MI Mason, GM Mazur, JE Dwyer, JR Popecki, MA Mobius, E Cohen, CMS Leske, RA TI ACE observations of the Bastille Day 2000 interplanetary disturbances SO SOLAR PHYSICS LA English DT Article ID ADVANCED-COMPOSITION-EXPLORER; ENERGETIC PARTICLE EVENTS; CORONAL MASS EJECTIONS; SOLAR-WIND; ISOTOPE SPECTROMETER; ALPHA-MONITOR; ACCELERATION; ABUNDANCES; SPACECRAFT; EVOLUTION AB We present ACE observations for the six-day period encompassing the Bastille Day 2000 solar activity. A high level of transient activity at 1 AU, including ICME-driven shocks, magnetic clouds, shock-accelerated energetic particle populations, and solar energetic ions and electrons, are described. We present thermal ion composition signatures for ICMEs and magnetic clouds from which we derive electron temperatures at the source of the disturbances and we describe additional enhancements in some ion species that are clearly related to the transient source. We describe shock acceleration of 0.3-2.0 MeV nucl(-1) protons and minor ions and the relative inability of some of the shocks to accelerate significant energetic ion populations near 1 AU. We report the characteristics of < 20 MeV nucl(-1) solar energetic ions and < 0.32 MeV electrons and attempt to relate the release of energetic electrons to particular source regions. C1 Univ Delaware, Bartol Res Inst, Newark, DE 19716 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. SW Res Inst, Space Sci & Engn Div, San Antonio, TX 78228 USA. Univ Michigan, Dept Atmospher Ocean & Space Sci, Ann Arbor, MI 48109 USA. Univ Maryland, Dept Phys, College Pk, MD 20742 USA. Johns Hopkins Univ, Appl Phys Lab, Laurel, MD 20723 USA. Univ Maryland, Inst Phys Sci & Technol, College Pk, MD 20742 USA. Aerosp Corp, El Segundo, CA 90245 USA. Florida Inst Technol, Melbourne, FL 32901 USA. Univ New Hampshire, Inst Study Earth Oceans & Space, Durham, NH 03824 USA. CALTECH, Pasadena, CA 91125 USA. RP Smith, CW (reprint author), Univ Delaware, Bartol Res Inst, Newark, DE 19716 USA. OI Moebius, Eberhard/0000-0002-2745-6978 NR 42 TC 26 Z9 28 U1 0 U2 1 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-0938 J9 SOL PHYS JI Sol. Phys. PD DEC PY 2001 VL 204 IS 1-2 BP 229 EP 254 PG 26 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 524BU UT WOS:000173992700015 ER PT J AU Jordanova, VK Thorne, RM Farrugia, CJ Dotan, Y Fennell, JF Thomsen, MF Reeves, GD McComas, DJ AF Jordanova, VK Thorne, RM Farrugia, CJ Dotan, Y Fennell, JF Thomsen, MF Reeves, GD McComas, DJ TI Ring current dynamics during the 13-18 July 2000 storm period SO SOLAR PHYSICS LA English DT Article ID ION-CYCLOTRON WAVES; SOLAR-WIND AB We study the development of the terrestrial ring current during the time interval of 13-18 July, 2000, which consisted of two small to moderate geomagnetic storms followed by a great storm with indices Dst=-300 nT and Kp=9. This period of intense geomagnetic activity was caused by three interplanetary coronal mass ejecta (ICME) each driving interplanetary shocks, the last shock being very strong and reaching Earth at similar to 14 UT on 15 July. We note that (a) the sheath region behind the third shock was characterized by B-z fluctuations of similar to35 nT peak-to-peak amplitude, and (b) the ICME contained a negative to positive B-z variation extending for about 1 day, with a similar to 6-hour long negative phase and a minimum B-z of about -55 nT. Both of these interplanetary sources caused considerable geomagnetic activity (Kp=8 to 9) despite their disparity as interplanetary triggers. We used our global ring current-atmosphere interaction model with initial and boundary conditions inferred from measurements from the hot plasma instruments on the Polar spacecraft and the geosynchronous Los Alamos satellites, and simulated the time evolution of H+, O+, and He+ ring current ion distributions. We found that the O+ content of the ring current increased after each shock and reached maximum values of similar to 60% near minimum Dst of the great storm. We calculated the growth rate of electromagnetic ion cyclotron waves considering for the first time wave excitation at frequencies below O+ gyrofrequency. We found that the wave gain of O+ band waves is greater and is located at larger L shells than that of the He+ band waves during this storm interval. Isotropic pitch angle distributions indicating strong plasma wave scattering were observed by the imaging proton sensor (IPS) on Polar at the locations of maximum predicted wave gain, in good agreement with model simulations. C1 Univ New Hampshire, Ctr Space Sci, Durham, NH 03824 USA. Univ Calif Los Angeles, Dept Atmospher Sci, Los Angeles, CA 90095 USA. Aerosp Corp, Los Angeles, CA 90009 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. SW Res Inst, San Antonio, TX 78228 USA. RP Jordanova, VK (reprint author), Univ New Hampshire, Ctr Space Sci, Durham, NH 03824 USA. RI Reeves, Geoffrey/E-8101-2011; OI Reeves, Geoffrey/0000-0002-7985-8098; Jordanova, Vania/0000-0003-0475-8743 NR 20 TC 24 Z9 24 U1 0 U2 2 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0038-0938 J9 SOL PHYS JI Sol. Phys. PD DEC PY 2001 VL 204 IS 1-2 BP 361 EP 375 DI 10.1023/A:1014241527043 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 524BU UT WOS:000173992700024 ER PT J AU Johnson, JW Baca, AG Briggs, RD Shul, RJ Wendt, JR Monier, C Ren, F Pearton, SJ Dabiran, AM Wowchack, AM Polley, CJ Chow, PP AF Johnson, JW Baca, AG Briggs, RD Shul, RJ Wendt, JR Monier, C Ren, F Pearton, SJ Dabiran, AM Wowchack, AM Polley, CJ Chow, PP TI Effect of gate length on DC performance of AlGaN/GaN HEMTs grown by MBE SO SOLID-STATE ELECTRONICS LA English DT Article DE GaN; AlGaN; HEMT; MBE; SEM; barrier height ID IN-SITU CATHODOLUMINESCENCE; FIELD-EFFECT TRANSISTORS; HIGH-FREQUENCY; MODULATION; MODFETS AB The DC performance of AlGaN/GaN high electron mobility transistors grown by plasma-assisted molecular beam epitaxy was investigated for gate lengths in the range 0.1-1.2 mum. On 0.25 mum gate length devices we obtained 40 V-DS operation with > 50 mA peak I-D. The peak drain current density was 0.44 A/mm for 100 mum gate width devices with 1.2 mum gate lengths. The extrinsic transconductance (g(m)) decreased with both gate length and gate width and was greater than or equal to 75 mS/mm for all gate widths for 0.25 pin devices. E-beam written gates typically produced a slightly lower Schottky barrier height than optically patterned gates. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Univ Florida, Dept Chem Engn, Gainesville, FL 32611 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. Univ Florida, Dept Mat Sci & Engn, Gainesville, FL 32611 USA. SVT Associates, Eden Prairie, MN USA. RP Ren, F (reprint author), Univ Florida, Dept Chem Engn, POB 116005, Gainesville, FL 32611 USA. NR 23 TC 27 Z9 27 U1 0 U2 5 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0038-1101 J9 SOLID STATE ELECTRON JI Solid-State Electron. PD DEC PY 2001 VL 45 IS 12 BP 1979 EP 1985 DI 10.1016/S0038-1101(01)00255-6 PG 7 WC Engineering, Electrical & Electronic; Physics, Applied; Physics, Condensed Matter SC Engineering; Physics GA 499CF UT WOS:000172552900002 ER EF