FN Thomson Reuters Web of Science™ VR 1.0 PT J AU Awana, VPS Karppinen, M Yamauchi, H Malik, SK Yelon, WB Mehta, A Narlikar, AV AF Awana, VPS Karppinen, M Yamauchi, H Malik, SK Yelon, WB Mehta, A Narlikar, AV TI Magnetization and heat capacity of R1/3Sr2/3FeO3-delta (R = La and Pr) SO IEEE TRANSACTIONS ON MAGNETICS LA English DT Article; Proceedings Paper CT 8th Joint Magnetism and Magnetic Materials International Magnetics Conference (MMM-INTERMAG) CY JAN 07-11, 2001 CL SAN ANTONIO, TEXAS DE heat capacity; magnetic ordering; single Fe perovskites ID CHARGE DISPROPORTIONATION; DOUBLE-PEROVSKITE; ROOM-TEMPERATURE; MAGNETORESISTANCE; TRANSITIONS; SPECTROSCOPY; SEPARATION; SYSTEM; IRON; GD AB Results of magnetization and heat capacity (C-P) measurements are presented for R1/3Sr2/3FeO3-delta compounds with R = La and Pr. The change in entropy (DeltaS) near the magnetic transition amounts to only 15% of the theoretically expected value for the Fe3+ or Fe5+ spins magnetic ordering. The lower value of DeltaS is explained on the basis of reported Mossbauer studies, which revealed a substantial amount of nonmagnetic Fe4+ in the compound across the magnetic transition. The C-P peak height across the magnetic transition increases substantially after annealing the samples in flowing oxygen. The symmetry in the C-P transitions points toward a structural phase transition coupled with magnetic ordering. The magnitude of DeltaS near the magnetic transition in these compounds depends on the synthesis procedure. C1 Tokyo Inst Technol, Mat & Struct Lab, Yokohama, Kanagawa 2268503, Japan. Tata Inst Fundamental Res, Bombay 400005, Maharashtra, India. Univ Missouri, Mat Res Ctr, Rolla, MO 65401 USA. Stanford Linear Accelerator Ctr, SSRL, Stanford, CA 94309 USA. Max Planck Inst Festkorperforsch, D-70569 Stuttgart, Germany. Natl Phys Lab, New Delhi 110012, India. RP Awana, VPS (reprint author), Tokyo Inst Technol, Mat & Struct Lab, Yokohama, Kanagawa 2268503, Japan. RI Karppinen, Maarit/G-8035-2012; Awana, Veer/E-4938-2015 NR 23 TC 1 Z9 1 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 0018-9464 J9 IEEE T MAGN JI IEEE Trans. Magn. PD JUL PY 2001 VL 37 IS 4 BP 2163 EP 2165 DI 10.1109/20.951112 PN 1 PG 3 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 471CW UT WOS:000170910900286 ER PT J AU Humfeld, KD Giri, AK Majetich, SA Venturini, EL AF Humfeld, KD Giri, AK Majetich, SA Venturini, EL TI Time dependent properties of iron nanoparticles SO IEEE TRANSACTIONS ON MAGNETICS LA English DT Article; Proceedings Paper CT 8th Joint Magnetism and Magnetic Materials International Magnetics Conference (MMM-INTERMAG) CY JAN 07-11, 2001 CL SAN ANTONIO, TEXAS DE AC; magnetic viscosity; nanoparticles; susceptibility ID DYNAMICS AB The magnetic relaxation and AC response of dilute dispersions of monodisperse Fe nanoparticles are reported. Magnetic relaxation shows the effect of magnetic alignment on the energy barrier distribution. C1 Carnegie Mellon Univ, Dept Phys, Pittsburgh, PA 15213 USA. Sandia Natl Labs, Nanostruct & Adv Mat Div, Albuquerque, NM 87185 USA. RP Humfeld, KD (reprint author), Carnegie Mellon Univ, Dept Phys, Pittsburgh, PA 15213 USA. RI Majetich, Sara/B-1022-2015 OI Majetich, Sara/0000-0003-0848-9317 NR 10 TC 20 Z9 20 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 0018-9464 J9 IEEE T MAGN JI IEEE Trans. Magn. PD JUL PY 2001 VL 37 IS 4 BP 2194 EP 2196 DI 10.1109/20.951121 PN 1 PG 3 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 471CW UT WOS:000170910900295 ER PT J AU Sorge, KD Thompson, JR Schulthess, TC Modine, FA Haynes, TE Honda, S Meldrum, A Budai, JD White, CW Boatner, LA AF Sorge, KD Thompson, JR Schulthess, TC Modine, FA Haynes, TE Honda, S Meldrum, A Budai, JD White, CW Boatner, LA TI Oriented, single domain Fe nanoparticle layers in single crystal yttria-stabilized zirconia SO IEEE TRANSACTIONS ON MAGNETICS LA English DT Article; Proceedings Paper CT 8th Joint Magnetism and Magnetic Materials International Magnetics Conference (MMM-INTERMAG) CY JAN 07-11, 2001 CL SAN ANTONIO, TEXAS DE anisotropy; Fe nanoparticles; magnetostatic interactions; textured materials ID ZRO2 AB To create an ensemble of oriented, single crystal particles of iron, Fe ions were implanted into the near-surface region of single crystal yttria-stabilized zirconia (YSZ). With thermal processing, the implanted species precipitated to form faceted, predominantly single-domain ferromagnetic nanoparticles. The YSZ substrate isolates, protects, and crystallographically textures the nanoparticles, creating a magnetically anisotropic layer. Experimental studies of the magnetization M(H, T) at various orientations of the applied field H show a major distinction only between H parallel to (n) over cap (hard direction) and H perpendicular to (n) over cap (easy direction) where (n) over cap is the surface normal; there is little angular variation within the plane. This feature and the behavior of the orientationally dependent coercive field H-c and magnetic remanence M-r are attributed to magnetostatic interactions between the particles. Non-interacting single-domain particles should show a Stoner-Wohlfarth-like behavior that is poorly approximated in this far-from-close-packed system. C1 Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Sorge, KD (reprint author), Oak Ridge Natl Lab, Div Solid State, POB 2008, Oak Ridge, TN 37831 USA. RI Haynes, Tony/P-8932-2015; Boatner, Lynn/I-6428-2013; Budai, John/R-9276-2016 OI Haynes, Tony/0000-0003-2871-4745; Boatner, Lynn/0000-0002-0235-7594; Budai, John/0000-0002-7444-1306 NR 10 TC 17 Z9 17 U1 0 U2 5 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9464 J9 IEEE T MAGN JI IEEE Trans. Magn. PD JUL PY 2001 VL 37 IS 4 BP 2197 EP 2199 DI 10.1109/20.951122 PN 1 PG 3 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 471CW UT WOS:000170910900296 ER PT J AU Puntes, VF Krishnan, KM AF Puntes, VF Krishnan, KM TI Synthesis, structural order and magnetic behavior of self-assembled epsilon-Co nanocrystal arrays SO IEEE TRANSACTIONS ON MAGNETICS LA English DT Article; Proceedings Paper CT 8th Joint Magnetism and Magnetic Materials International Magnetics Conference (MMM-INTERMAG) CY JAN 07-11, 2001 CL SAN ANTONIO, TEXAS DE chemical synthesis of ferrofluids; Co nanocrystals; finite size effects; self assembly ID SUPERLATTICES; COBALT AB The synthesis of magnetic nanoparticles with monodispere size distributions, their self assembly into ordered arrays and their magnetic behavior as a function of structural order (ferrofluids and 2D assemblies) are presented. Magnetic colloids of monodispersed, passivated, cobalt nanocrystals were produced by the rapid pyrolysis of cobalt carbonyl in solution. The size, size distribution (std. dev. < 5%) and the shape of the nanocrystals were controlled by varying the surfactant, its concentration, the reaction rate and the reaction temperature. The Co particles are defect-free single crystals with a complex cubic structure related to the beta phase of manganese (E-Co). In the 2D assembly, a collective behavior was observed in the low-field susceptibility measurements where the magnetization of the zero field cooled process increases steadily and the magnetization of the field cooling process is independent the temperature. This was different from the observed behavior in a sample comprised of disordered interacting particles. A strong paramagnetic contribution appears at very low temperatures where the magnetization increases drastically after field cooling the sample. This has been attributed to the Co surfactant-particle interface since no magnetic atomic impurities are present in these samples. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Puntes, VF (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RI Puntes, Victor/F-8407-2013 OI Puntes, Victor/0000-0001-8996-9499 NR 15 TC 36 Z9 36 U1 2 U2 22 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9464 J9 IEEE T MAGN JI IEEE Trans. Magn. PD JUL PY 2001 VL 37 IS 4 BP 2210 EP 2212 DI 10.1109/20.951126 PN 1 PG 3 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 471CW UT WOS:000170910900300 ER PT J AU Lo, CCH Snyder, JE Leib, J Wang, D Qian, Z Daughton, JM Jiles, DC AF Lo, CCH Snyder, JE Leib, J Wang, D Qian, Z Daughton, JM Jiles, DC TI Magnetization reversal in CoFeHfO films SO IEEE TRANSACTIONS ON MAGNETICS LA English DT Article; Proceedings Paper CT 8th Joint Magnetism and Magnetic Materials International Magnetics Conference (MMM-INTERMAG) CY JAN 07-11, 2001 CL SAN ANTONIO, TEXAS DE amorphous and nanocrystalline materials and; devices; magnetic domains; magnetic microscopy and imaging; soft magnetic materials ID NANOCRYSTALLINE AB Magnetization reversals of a thick CoFeHfO film (800 nm), and a thin CoFeHfO (10 mu) film overcoated with CrSi (10 mn) have been studied by magnetic force microscopy (MFM) with in situ applied field capability. The CoFeHfO layers were deposited by rf sputtering and annealed in a magnetic field to induce an in-plane uniaxial anisotropy. For easy-axis applied fields both samples showed significant switching of NUM image contrast for fields approximately equal to the coercivity. This is consistent with the high easy-axis coercive squareness of the films. For hard-axis applied fields the thin CoFeHfO film displayed a distinctive reversal process: a ripple-like domain pattern formed and rotated gradually as the reversed field was increased. The image contrast increased, reached a maximum when the ripple-like features aligned perpendicular to the field and then diminished as the sample approached saturation. The observed magnetization reversal processes appear to be consistent with the formation of magnetization ripples which rotate toward the hard-axis applied field. C1 Iowa State Univ, USDoE, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Mat Sci & Engn, Ames, IA 50011 USA. Nonvolatile Elect Inc, Eden Prairie, MN 55344 USA. RP Lo, CCH (reprint author), Iowa State Univ, USDoE, Ames Lab, Ames, IA 50011 USA. RI Jiles, David/H-9548-2012 NR 5 TC 13 Z9 13 U1 0 U2 5 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9464 J9 IEEE T MAGN JI IEEE Trans. Magn. PD JUL PY 2001 VL 37 IS 4 BP 2337 EP 2339 DI 10.1109/20.951165 PN 1 PG 3 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 471CW UT WOS:000170910900339 ER PT J AU Lee, SJ Zhu, B Lo, CCH Clatterbuck, DM Jiles, DC AF Lee, SJ Zhu, B Lo, CCH Clatterbuck, DM Jiles, DC TI Application of non-linear Barkhausen model incorporating anhysteretic susceptibility to annealed low carbon Fe sample SO IEEE TRANSACTIONS ON MAGNETICS LA English DT Article; Proceedings Paper CT 8th Joint Magnetism and Magnetic Materials International Magnetics Conference (MMM-INTERMAG) CY JAN 07-11, 2001 CL SAN ANTONIO, TEXAS DE anhysteresis; Barkhausen effect; hysteresis loop; magnetic modeling ID HYSTERESIS AB The Alessandro, Beatrice, Bertotti, and Montorsi (ABBM) model can describe the dynamics of domain wall motion in a ferromagnetic material which is subjected to a smoothly varying external magnetic field. The assumptions of this model limit its use to experiments where the differential permeability and time derivative of applied field are constant. In this paper, the anhysteretic susceptibility is incorporated into the model of ABBM model instead of a constant differential permeability. The resulting simulated Barkhausen signal can accurately describe experimental data from a low carbon iron sample. C1 Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Berkeley, CA 94270 USA. Univ Calif Berkeley, Dept Mat Sci & Mineral Engn, Berkeley, CA 94270 USA. RP Lee, SJ (reprint author), Iowa State Univ, Ames Lab, Ames, IA 50011 USA. RI Jiles, David/H-9548-2012 NR 10 TC 0 Z9 0 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 0018-9464 J9 IEEE T MAGN JI IEEE Trans. Magn. PD JUL PY 2001 VL 37 IS 4 BP 2340 EP 2342 DI 10.1109/20.951166 PN 1 PG 3 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 471CW UT WOS:000170910900340 ER PT J AU Vlasko-Vlasov, VK Welp, U Jiang, JS Inomata, A Miller, DJ Crabtree, GW Bader, SD AF Vlasko-Vlasov, VK Welp, U Jiang, JS Inomata, A Miller, DJ Crabtree, GW Bader, SD TI Magneto-optical study of exchange spring degradation SO IEEE TRANSACTIONS ON MAGNETICS LA English DT Article; Proceedings Paper CT 8th Joint Magnetism and Magnetic Materials International Magnetics Conference (MMM-INTERMAG) CY JAN 07-11, 2001 CL SAN ANTONIO, TEXAS DE biquadratic exchange; exchange coupling; magnetic multilayers; magnetic reversal ID FILMS; MULTILAYERS; ANISOTROPY; COERCIVITY; BILAYERS AB Magnetic structures of SmCo/Fe bilayers during remagnetization and after multiple field cycling are studied magneto-optically (MO). Rotation of the remanent magnetization in the soft Fe layer away from the easy axis is found after large enough remagnetizing fields. This is indicative of the appearance of biquadratic coupling between the layers. It is explained by the fluctuation exchange mechanism due to the field induced magnetic inhomogeneity of the hard layer. Such an inhomogeneity revealed in the MO patterns also explains the degradation of the bias field in exchange springs. C1 Argonne Natl Lab, Argonne, IL 60439 USA. Inst Solid State Phys, Chernogolovka 142432, Russia. Fujitsu Ltd, Atsugi, Kanagawa, Japan. RP Vlasko-Vlasov, VK (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Bader, Samuel/A-2995-2013 NR 15 TC 1 Z9 1 U1 0 U2 1 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9464 J9 IEEE T MAGN JI IEEE Trans. Magn. PD JUL PY 2001 VL 37 IS 4 BP 2424 EP 2427 DI 10.1109/20.951192 PN 1 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 471CW UT WOS:000170910900366 ER PT J AU Lewis, LH Collins, SM Kramer, MJ Lo, CCH AF Lewis, LH Collins, SM Kramer, MJ Lo, CCH TI Solidification, quenching gas and magnetic properties in melt-spun Nd2Fe14B SO IEEE TRANSACTIONS ON MAGNETICS LA English DT Article; Proceedings Paper CT 8th Joint Magnetism and Magnetic Materials International Magnetics Conference (MMM-INTERMAG) CY JAN 07-11, 2001 CL SAN ANTONIO, TEXAS DE magnetic force microscopy; microstructure; permanent magnet; rapid solidification AB Magnetic measurement and cross-sectional Magnetic Force Microscopy images were obtained from Nd2Fe14B ribbons melt-quenched at a circumferential wheel speed of 10 m/sec in three different atmospheres: I atm Ar, I atm He and 1/3 atm He. The striking effects of the quenching gas type upon the microstructure is correlated with room-temperature demagnetization curves that confirm the presence of multiple, yet discontinuous, grain size zones. A model for the rapid solidification of Nd2Fe14B based on consideration of recalescence relative to the peritectic temperature is invoked to explain the experimental results. The recalescence causes breakup of the Nd2Fe14B dendrites formed during the first phase of solidification and results in a layered structure within the ribbon possessing distinct transition regions where the solidification front temperature crosses the peritectic temperature. C1 Brookhaven Natl Lab, Energy Sci & Technol Dept, Div Mat & Chem Sci, Upton, NY 11973 USA. Iowa State Univ, Dept Mat Sci & Engn, Ames, IA 50011 USA. USDOE, Ames Lab, Ames, IA 50011 USA. RP Lewis, LH (reprint author), Brookhaven Natl Lab, Energy Sci & Technol Dept, Div Mat & Chem Sci, Upton, NY 11973 USA. NR 7 TC 3 Z9 3 U1 2 U2 4 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9464 J9 IEEE T MAGN JI IEEE Trans. Magn. PD JUL PY 2001 VL 37 IS 4 BP 2486 EP 2488 DI 10.1109/20.951211 PN 1 PG 3 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 471CW UT WOS:000170910900385 ER PT J AU Woodward, RC Gorham, NT Street, R Crew, DC Girt, E Krishnan, KM AF Woodward, RC Gorham, NT Street, R Crew, DC Girt, E Krishnan, KM TI Coercivity, time dependence and reversible magnetization in Nd rich Nd-Fe-B alloys SO IEEE TRANSACTIONS ON MAGNETICS LA English DT Article; Proceedings Paper CT 8th Joint Magnetism and Magnetic Materials International Magnetics Conference (MMM-INTERMAG) CY JAN 07-11, 2001 CL SAN ANTONIO, TEXAS DE coercivity; magnetic viscosity; magnetization processes; Nd-Fe-B ID BEHAVIOR AB The coercivity, time dependent magnetic properties and reversible magnetization behavior for a series of neodymium enriched alloys based on Nd2Fe14B has been investigated. These studies were carried out in an attempt to elucidate the dramatic increase in the coercivity in these materials with increasing dilution, of the magnetic phase (Nd2Fe14B). Good correlation between the coercivity and the relative average linear spacing between magnetic grains was found for all but the lowest Nd content. As the Nd content is increased the reversible magnetization associated with domain wall pinning decreases. At high dilutions the reversible magnetization behavior is consistent with the predictions of a Stoner-Wohlfarth model of an assembly of noninteracting single domain particles. The magnetic viscosity parameter, Lambda, does not vary consistently with dilution or coercivity. C1 Univ Western Australia, Dept Phys, Nedlands, WA 6907, Australia. Brookhaven Natl Lab, Div Mat & Chem Sci, Energy Sci & Technol Dept, Upton, NY 11973 USA. Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Woodward, RC (reprint author), Univ Western Australia, Dept Phys, Nedlands, WA 6907, Australia. RI Woodward, Robert/A-1397-2008 OI Woodward, Robert/0000-0001-8913-6091 NR 13 TC 1 Z9 1 U1 0 U2 4 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9464 J9 IEEE T MAGN JI IEEE Trans. Magn. PD JUL PY 2001 VL 37 IS 4 BP 2493 EP 2496 DI 10.1109/20.951213 PN 1 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 471CW UT WOS:000170910900387 ER PT J AU Kramer, MJ O'Connor, AS Dennis, KW McCallum, RW Lewis, LH Tung, LD Duong, NP AF Kramer, MJ O'Connor, AS Dennis, KW McCallum, RW Lewis, LH Tung, LD Duong, NP TI Origins of coercivity in the amorphous alloy Nd-Fe-Al SO IEEE TRANSACTIONS ON MAGNETICS LA English DT Article; Proceedings Paper CT 8th Joint Magnetism and Magnetic Materials International Magnetics Conference (MMM-INTERMAG) CY JAN 07-11, 2001 CL SAN ANTONIO, TEXAS DE bulk metallic glass; coercivity; high temperature X-ray diffraction; microstructure ID MAGNETIC-PROPERTIES AB Results obtained from detailed studies of the microstructure and devitrification behavior, as revealed by advanced electron micrsocopy and synchrotron x-ray diffraction techniques, were compared with magnetic and thermal analysis characterization to obtain insight into the appreciable coercivity of nominally-amorphous melt-spun ribbon of Nd60-2/3xFe30-1/3xAl10+x (-2 < x < 6.5). The as-spun microstructure consists of an amorphous Nd-rich, magnetically-soft matrix with clusters of approximate 1.2 nm diameter that apparently confer the hard magnetic properties to the alloy. The clusters are tentatively identified as sub-unit-cells of Nd6Fe13-xAl1+x, by virtue of their unique and analogous temperature-dependent magnetic character as well as considerations of the ternary phase relationships during solidification. C1 USDOE, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Mat Sci & Engn, Ames, IA 50011 USA. Brookhaven Natl Lab, Energy Sci & Technol Dept, Div Mat & Chem Sci, Upton, NY 11973 USA. ITIMS, Hanoi, Vietnam. RP Kramer, MJ (reprint author), USDOE, Ames Lab, Ames, IA 50011 USA. NR 8 TC 43 Z9 43 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 0018-9464 J9 IEEE T MAGN JI IEEE Trans. Magn. PD JUL PY 2001 VL 37 IS 4 BP 2497 EP 2499 DI 10.1109/20.951214 PN 1 PG 3 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 471CW UT WOS:000170910900388 ER PT J AU Meacham, BE Shield, JE Branagan, DJ AF Meacham, BE Shield, JE Branagan, DJ TI Control of ordering and microstructure in Pr-Co and Sm-Fe alloys for permanent magnets SO IEEE TRANSACTIONS ON MAGNETICS LA English DT Article; Proceedings Paper CT 8th Joint Magnetism and Magnetic Materials International Magnetics Conference (MMM-INTERMAG) CY JAN 07-11, 2001 CL SAN ANTONIO, TEXAS DE alloy design; microstructural engineering; order-disorder transitions; Pr-Co alloys; Sm-Fe alloys ID SM2FE17NX AB In this study, the structural state and microstructural scale of Pr2Co17 and Sm2Fe17 were modified by rapid solidification and alloying. Partial suppression of the dumbbell ordering was accomplished by melt spinning, and more effective suppression, leading to the formation of the TbCu7-type structure, was accomplished by the addition of Ti or Ti and C. Annealing recovered the order, although Ti and TiC significantly affected the kinetics in the Sm-Fe system. The addition of Ti and C refines the grain size in both Pr-Co and Sm-Fe. The degree of order was found to influence the coercivity in the nitrided Sm-Fe alloys. The Pr-Co alloys were found to have a planar easy magnetization direction at all levels of ordering. C1 Univ Utah, Dept Mat Sci & Engn, Salt Lake City, UT 84112 USA. Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. RP Meacham, BE (reprint author), Univ Utah, Dept Mat Sci & Engn, Salt Lake City, UT 84112 USA. NR 14 TC 9 Z9 10 U1 0 U2 4 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9464 J9 IEEE T MAGN JI IEEE Trans. Magn. PD JUL PY 2001 VL 37 IS 4 BP 2503 EP 2505 DI 10.1109/20.951216 PN 1 PG 3 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 471CW UT WOS:000170910900390 ER PT J AU Crew, DC Lewis, LH AF Crew, DC Lewis, LH TI Effect of grain alignment on magnetic structure in nanoscale material SO IEEE TRANSACTIONS ON MAGNETICS LA English DT Article; Proceedings Paper CT 8th Joint Magnetism and Magnetic Materials International Magnetics Conference (MMM-INTERMAG) CY JAN 07-11, 2001 CL SAN ANTONIO, TEXAS DE coercivity; interaction domains; micromagnetic modeling; NdFeB ID NANOCRYSTALLINE PERMANENT-MAGNETS AB Intergranular exchange interactions act to bind nanograins in nanoscale magnetic materials into larger interaction domains with a magnetic structure considerably larger than that of a single grain. To investigate the effect of differing. relative grain orientation on the scale of the interaction domains in melt-quenched Nd2Fe14B, a two-dimensional micromagnetic model has been used. The model consists of 18 grains characterized by the intrinsic properties of Nd2Fe14B. Two cases are considered; one with a narrow distribution of easy axis orientations. centered along the applied field direction and one with a nearly isotropic easy axis distribution. Computational results confirm that the scale of the magnetic structure for well-aligned material is. very large, while for isotropic material only a few grains can be coupled into an interaction domain before the intergranular misalignment is large enough to pin domain walls and impede reversal. C1 Brookhaven Natl Lab, Div Mat & Chem Sci, Energy Sci & Technol Dept, Upton, NY 11973 USA. RP Crew, DC (reprint author), Brookhaven Natl Lab, Div Mat & Chem Sci, Energy Sci & Technol Dept, Upton, NY 11973 USA. NR 9 TC 4 Z9 4 U1 1 U2 10 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9464 J9 IEEE T MAGN JI IEEE Trans. Magn. PD JUL PY 2001 VL 37 IS 4 BP 2512 EP 2514 DI 10.1109/20.951219 PN 1 PG 3 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 471CW UT WOS:000170910900393 ER PT J AU Zhang, Y Tang, W Hadjipanayis, GC Chen, C Nelson, C Krishnan, K AF Zhang, Y Tang, W Hadjipanayis, GC Chen, C Nelson, C Krishnan, K TI Evolution of microstructure, microchemistry and coercivity in 2 : 17 type Sm-Co magnets with heat treatment SO IEEE TRANSACTIONS ON MAGNETICS LA English DT Article; Proceedings Paper CT 8th Joint Magnetism and Magnetic Materials International Magnetics Conference (MMM-INTERMAG) CY JAN 07-11, 2001 CL SAN ANTONIO, TEXAS DE coercivity; microchemistry; microstructure; Sm-Co ID PERMANENT-MAGNETS AB A systematic study has been undertaken to understand the evolution of microstructure, microchemistry, and coercivity of sintered SM(CobalCu0.06Fe0.015Zr0.027)(6.4) magnets with heat treatment using magnetometry, transmission electron microscopy, Lorentz microscopy, and nanoprobe chemical analysis. In general, the homogenized and quenched SM(CObalCu0.06Fe0.015Zr0.027)(6.4) magnets have a featureless microstructure with the 2:17 hexagonal structure. During isothermal aging at 700-850 degreesC, the 1:5 nuclei precipitate and then coalesce and start forming the cellular structure with 2:17 rhombohedral cells surrounded by 1:5 hexagonal cell boundaries. Uniform cellular and lamellar structures are formed after 2 hours of isothermal aging, and both the cell size and density of lamella phase slightly increase with longer aging. Nanoprobe chemical analysis shows that the Cu content in 1:5 cell boundaries increases during the slow cooling to lower temperatures, reaching a maximum value around 500 degreesC, which is consistent with the development of coercivity. Also the Cu content in the triple cell boundary junctions is twice as much as the amount at the regular cell boundaries regardless of cell size and boundary width. Lorentz microscopy indicates that the triple cell boundary junctions may play a major role in domain wall pinning. C1 Univ Delaware, Dept Phys & Astron, Newark, DE 19716 USA. Electron Energy Corp, Landisville, PA 17538 USA. Lawrence Berkeley Natl Lab, Berkeley, CA 94152 USA. RP Zhang, Y (reprint author), Univ Delaware, Dept Phys & Astron, Newark, DE 19716 USA. NR 13 TC 23 Z9 26 U1 2 U2 8 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9464 J9 IEEE T MAGN JI IEEE Trans. Magn. PD JUL PY 2001 VL 37 IS 4 BP 2525 EP 2527 DI 10.1109/20.951223 PN 1 PG 3 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 471CW UT WOS:000170910900397 ER PT J AU Shull, RD Shapiro, AJ Gornakov, VS Nikitenko, VI Jiang, JS Kaper, H Leaf, G Bader, SD AF Shull, RD Shapiro, AJ Gornakov, VS Nikitenko, VI Jiang, JS Kaper, H Leaf, G Bader, SD TI Spin spring behavior in exchange coupled soft and high-coercivity hard ferromagnets SO IEEE TRANSACTIONS ON MAGNETICS LA English DT Article; Proceedings Paper CT 8th Joint Magnetism and Magnetic Materials International Magnetics Conference (MMM-INTERMAG) CY JAN 07-11, 2001 CL SAN ANTONIO, TEXAS DE exchange spring; magnetization reversal; permanent magnet; SmCo; thin film ID MAGNET AB The magnetization reversal processes in an epitaxial Fe/SM2Co7 structure were investigated using the magneto-optical indicator film technique. The dependence of the magnitude and the orientation of the structure average magnetization have been studied on both cycling and rotating the external magnetic field. Magnetization reversal of the soft ferromagnet was found to proceed by the formation of exchange springs due to spin winding in both the thickness and perpendicular directions as adjacent subdomains with opposite chirality are created. Experimental data is compared with a theoretical estimation of the rotational hysteresis loop for a spin system containing a one-dimensional (single chirality) exchange spring. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Argonne Natl Lab, Argonne, IL 60439 USA. RP Shull, RD (reprint author), Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RI Bader, Samuel/A-2995-2013; Shull, Robert/F-5971-2013 NR 5 TC 12 Z9 12 U1 0 U2 8 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9464 J9 IEEE T MAGN JI IEEE Trans. Magn. PD JUL PY 2001 VL 37 IS 4 BP 2576 EP 2578 DI 10.1109/20.951240 PN 1 PG 3 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 471CW UT WOS:000170910900414 ER PT J AU De Graef, M Willard, MA McHenry, ME Zhu, YM AF De Graef, M Willard, MA McHenry, ME Zhu, YM TI In-situ Lorentz TEM cooling study of magnetic domain configurations in Ni2MnGa SO IEEE TRANSACTIONS ON MAGNETICS LA English DT Article; Proceedings Paper CT 8th Joint Magnetism and Magnetic Materials International Magnetics Conference (MMM-INTERMAG) CY JAN 07-11, 2001 CL SAN ANTONIO, TEXAS DE ferromagnetic shape memory alloy; magnetic domains; phase reconstruction; phase transformation ID PHASE AB Magnetic domain configurations in the ferromagnetic shape memory alloy Ni2MnGa are analyzed by means of Lorentz microscopy and noninterferometric phase reconstruction methods. Domain structures in the cubic phase consist of cross-tie walls in the thinnest portions of the foil, and more complex configurations in thicker regions. At low temperature, the magnetization configurations change as the structure transforms martensitically to a tetragonal phase. A simple model for the magnetization changes is proposed. C1 Carnegie Mellon Univ, Dept Mat Sci & Engn, Pittsburgh, PA 15213 USA. USN, Res Lab, Washington, DC 20375 USA. Brookhaven Natl Lab, Div Mat Sci, Upton, NY 11973 USA. RP De Graef, M (reprint author), Carnegie Mellon Univ, Dept Mat Sci & Engn, Pittsburgh, PA 15213 USA. RI Willard, Matthew/A-8492-2009; McHenry, Michael/B-8936-2009; DeGraef, Marc/G-5827-2010 OI Willard, Matthew/0000-0001-5052-8012; DeGraef, Marc/0000-0002-4721-6226 NR 11 TC 23 Z9 23 U1 3 U2 12 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9464 J9 IEEE T MAGN JI IEEE Trans. Magn. PD JUL PY 2001 VL 37 IS 4 BP 2663 EP 2665 DI 10.1109/20.951267 PN 1 PG 3 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 471CW UT WOS:000170910900441 ER PT J AU Clark, AE Wun-Fogle, M Restorff, JB Lograsso, TA Cullen, JR AF Clark, AE Wun-Fogle, M Restorff, JB Lograsso, TA Cullen, JR TI Effect of quenching on the magnetostriction of Fe1-xGax (0.13 < x < 0.21) SO IEEE TRANSACTIONS ON MAGNETICS LA English DT Article; Proceedings Paper CT 8th Joint Magnetism and Magnetic Materials International Magnetics Conference (MMM-INTERMAG) CY JAN 07-11, 2001 CL SAN ANTONIO, TEXAS DE actuator; iron-gallium alloys; magnetostriction; structural materials; transduction AB The magnetostriction (lambda (100)) of b.c.c. Fe is increased over 10-fold at room temperature by the substitution of similar to 20% gallium for Fe. Fe1-x Ga-x alloyswith x between 0.19 and 0.214 that are quenched from 800 degreesC exhibit magnetostrictions similar to 25 % higher than those furnace-cooled at 10 degrees /min. We propose that this great increase of magnetostriction above that of Fe in Fe-Ga alloys is not due to conventional magnetoelastic effects but due to the substitutive presence of asymmetrically shaped clusters of the Ga atoms. As the concentration of solute atoms approaches 25%, the lattice becomes relaxed with formation of a more ordered structure and the magnetostriction decreases in value. C1 Clark Associates, Adelphi, MD 20783 USA. USN, Ctr Surface Warfare, Carderock Div, Bethesda, MD 20817 USA. Ames Lab, Ames, IA 50011 USA. Univ Maryland, College Pk, MD 20742 USA. RP Clark, AE (reprint author), Clark Associates, Adelphi, MD 20783 USA. NR 5 TC 183 Z9 202 U1 5 U2 30 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9464 J9 IEEE T MAGN JI IEEE Trans. Magn. PD JUL PY 2001 VL 37 IS 4 BP 2678 EP 2680 DI 10.1109/20.951272 PN 1 PG 3 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 471CW UT WOS:000170910900446 ER PT J AU Denbeaux, G Fischer, P Kusinski, G Le Gros, M Pearson, A Attwood, D AF Denbeaux, G Fischer, P Kusinski, G Le Gros, M Pearson, A Attwood, D TI A full field transmission X-ray microscope as a tool for high-resolution magnetic imaging SO IEEE TRANSACTIONS ON MAGNETICS LA English DT Article; Proceedings Paper CT 8th Joint Magnetism and Magnetic Materials International Magnetics Conference (MMM-INTERMAG) CY JAN 07-11, 2001 CL SAN ANTONIO, TEXAS DE high-resolution; magnetic imaging; x-ray microscopy AB The XM-1 soft x-ray microscope is a user-dedicated facility located at the Advanced Light Source at Lawrence Berkeley National Laboratory and has recently been established as a tool for high-resolution imaging of magnetic domains. It is a conventional full field transmission microscope which is able to achieve a resolution of 25 nm by using high-precision zone plates. It uses off-axis bend-magnet radiation to illuminate samples with elliptically polarized light. When the illumination energy is tuned to absorption edges of specific elements, it can be used as an element-specific probe of magnetism on the 25 nm scale with contrast provided by magnetic circular dichroism. The illumination energy can be adjusted between 250-850 eV. This allows magnetic imaging of elements including chromium, iron and cobalt. The spectral resolution has been shown to be E/DeltaE = 500-700. This spectral resolution allows a high sensitivity so that magnetization has been imaged within layers as thin as 3 mu. Since this is a photon based magnetic microscopy, fields can be applied to the sample even during imaging without affecting the spatial resolution. The current system can apply in-plane or out-of-plane fields of a few kOe. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Xray Opt, Berkeley, CA 94720 USA. Univ Wurzburg, D-97070 Wurzburg, Germany. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Denbeaux, G (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Xray Opt, Berkeley, CA 94720 USA. RI Fischer, Peter/A-3020-2010 OI Fischer, Peter/0000-0002-9824-9343 NR 12 TC 10 Z9 12 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 0018-9464 J9 IEEE T MAGN JI IEEE Trans. Magn. PD JUL PY 2001 VL 37 IS 4 BP 2764 EP 2766 DI 10.1109/20.951300 PN 1 PG 3 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 471CW UT WOS:000170910900474 ER PT J AU Chen, YH Jiles, DC AF Chen, YH Jiles, DC TI The magnetomechanical effect under torsional stress in a cobalt ferrite composite SO IEEE TRANSACTIONS ON MAGNETICS LA English DT Article; Proceedings Paper CT 8th Joint Magnetism and Magnetic Materials International Magnetics Conference (MMM-INTERMAG) CY JAN 07-11, 2001 CL SAN ANTONIO, TEXAS DE law of approach; magnetomechanical effect; torsional stress AB Metal bonded cobalt ferrite composites are candidate materials for torque sensor applications because of their high magnetostriction lambda and particularly the high value of the derivative d lambda /dH. This paper reports on recent investigations of the magnetomechanical effect under torsional stress in (CoFe2O3)(0.98)(Ag0.97Ni0.03)(0.02). Magnetic and magnetomechanical properties were measured and the law of approach was used to model the effect of changing torsional stress on magnetization. In the model calculations an effective magnetic field due to the torsional stress was considered in order to calculate the anhysteretic magnetization. The change of amplitude and orientation of magnetization was determined by considering magnetoelastic, magnetostatic and anisotropic energies using a generalization of a model proposed by Garshelis. The measured and modeled results were in good agreement giving magnetomechanical sensitivities of 61 and 65 A/m per N(.)m, respectively. C1 Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. RP Chen, YH (reprint author), Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. RI Jiles, David/H-9548-2012 NR 9 TC 14 Z9 16 U1 1 U2 9 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9464 J9 IEEE T MAGN JI IEEE Trans. Magn. PD JUL PY 2001 VL 37 IS 4 BP 3069 EP 3072 DI 10.1109/20.947066 PN 2 PG 4 WC Engineering, Electrical & Electronic; Physics, Applied SC Engineering; Physics GA 471CY UT WOS:000170911100021 ER PT J AU Kewley, DL Bouchard, JF AF Kewley, DL Bouchard, JF TI DARPA information assurance program dynamic defense experiment summary SO IEEE TRANSACTIONS ON SYSTEMS MAN AND CYBERNETICS PART A-SYSTEMS AND HUMANS LA English DT Article DE command and control systems; computer network security ID INTRUSION DETECTION AB Several types of experiments are being conducted by the Defense Advanced Research Projects Agency (DARPA) Information Assurance (IA) Program in DARPA's IA Lab. This research program is driven by concepts of strategic cyberdefense. Each experiment involves a carefully formulated hypothesis that is intended to be either supported or refuted by the experimental testing, In many cases, "red team" attackers participate in all phases of the experiment and contribute to generating the data required to test the hypothesis, The red team is usually structured to model a well-resourced adversary, such as a foreign, national intelligence agency. The particular experiment described here explored one aspect of the IA program's grand hypothesis of dynamic defense: "Dynamic modification of defensive structure improves system assurance." This experiment concentrated on the assertion that autonomic response mechanisms can improve overall system assurance by thwarting an attack while it is underway, In most cases, each attack in this experiment was run First with only "prevent and detect" mechanisms enabled, then repeated with "prevent, detect, and respond mechanisms" enabled. The key result of this experiment is that the hypothesis was supported. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Kewley, DL (reprint author), BBN Technol, Arlington, VA 22209 USA. NR 31 TC 14 Z9 15 U1 0 U2 5 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 1083-4427 J9 IEEE T SYST MAN CY A JI IEEE Trans. Syst. Man Cybern. Paart A-Syst. Hum. PD JUL PY 2001 VL 31 IS 4 BP 331 EP 336 DI 10.1109/3468.935052 PG 6 WC Computer Science, Cybernetics; Computer Science, Theory & Methods SC Computer Science GA 453YE UT WOS:000169945100011 ER PT J AU Hale, T Asaki, T AF Hale, T Asaki, T TI Optical resonant ultrasound spectroscopy for fluid properties measurement SO IEEE TRANSACTIONS ON ULTRASONICS FERROELECTRICS AND FREQUENCY CONTROL LA English DT Article ID SPHERICAL RESONATOR; SOUND; STATE; TEMPERATURE; EQUATION; TARGETS; SPEED; EMF AB The properties of fluids are studied using unusually small containment spherical resonators. Proper identification of resonant fluid signatures allows determination of pressure and density of the internal gas with great accuracy using an appropriate equation of state (EOS). Low noise and high sensitivity detection of vibration are critical parameters to characterizing the contained gas when its pressure approaches 1 atm or less. The benefits of using spherical resonators to determine fluid properties are discussed, and some example calculations of sound speed are presented. In addition to measuring fluids, a comparative experimental approach is taken to explore and, eventually, to optimize vibration detection. In the experiments, two detection methods, a contact piezoelectric transducer (PZT) device and a non-contact optical device, are compared simultaneously and quantitatively. This is done in a unique manner without change in vibration coupling to the sample between tests. A commercially available resonant ultrasound spectroscopy system is used as the contact system, while another commercial device (used as the non-contact vibration detector) combined with the same excitation source (used in the contact system) comprises the other system. The non-contact detector is an optical interferometric receiver that provides adaptation to optically rough surfaces and high sensitivity to acoustic displacements through optical interference in photorefractive GaAs. Both vibration detection systems are compared with particular emphasis on displacement sensitivity, frequency response, and noise level. Furthermore, the results from comparing detection modalities are presented, and their effects on fluid properties measurement are discussed. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. EM thale@lanl.gov NR 20 TC 1 Z9 1 U1 0 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 0885-3010 EI 1525-8955 J9 IEEE T ULTRASON FERR JI IEEE Trans. Ultrason. Ferroelectr. Freq. Control PD JUL PY 2001 VL 48 IS 4 BP 879 EP 885 DI 10.1109/58.935704 PG 7 WC Acoustics; Engineering, Electrical & Electronic SC Acoustics; Engineering GA 452RX UT WOS:000169873500006 PM 11477779 ER PT J AU Yoo, YK Ohnishi, T Wang, G Duewer, F Xiang, XD Chu, YS Mancini, DC Li, YQ O'Handley, RC AF Yoo, YK Ohnishi, T Wang, G Duewer, F Xiang, XD Chu, YS Mancini, DC Li, YQ O'Handley, RC TI Continuous mapping of structure-property relations in Fe1-xNix metallic alloys fabricated by combinatorial synthesis SO INTERMETALLICS LA English DT Article DE magnetic properties; phase diagram ID COMPOSITION-SPREAD; THIN-FILMS; DISCOVERY; OPTIMIZATION; IDENTIFICATION; LIBRARIES; PHOSPHOR AB A combinational approach has been taken to the linkage of composition and magnetic properties of Fe-Ni alloys. This linkage has been addressed by preparing the entire range of the binary alloys on a single material chip, in the form of a "continuous phase diagram'. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Intematix Corp, Moraga, CA 94556 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Environm Energy Technol Div, Berkeley, CA 94720 USA. Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. MIT, Dept Mat Sci & Engn, Cambridge, MA 02139 USA. RP Xiang, XD (reprint author), Intematix Corp, 351 Rheem Blvd, Moraga, CA 94556 USA. RI Xiang, Xiaodong/A-9445-2012; Xiang, Xiaodong/A-5936-2017 NR 32 TC 28 Z9 31 U1 1 U2 7 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 JUL PY 2001 VL 9 IS 7 BP 541 EP 545 DI 10.1016/S0966-9795(01)00030-9 PG 5 WC Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering GA 470QE UT WOS:000170882000001 ER PT J AU Krone, CA Wyse, EJ Ely, JTA AF Krone, CA Wyse, EJ Ely, JTA TI Cadmium in zinc-containing mineral supplements SO INTERNATIONAL JOURNAL OF FOOD SCIENCES AND NUTRITION LA English DT Article ID CALCIUM SUPPLEMENTS; CHILDREN; LEAD AB Seven zinc-containing dietary supplements were analyzed for zinc (Zn) and cadmium (Cd) by inductively coupled plasma/mass spectrometry (ICP/MS). Cadmium was detected in all samples; however, the amount of Cd per 15 mg Zn (the daily US Recommended Dietary Allowance) varied by over 37-fold (0.039 to 1.46 mug Cd/15 mg Zn). Supplements with Zn in the form of a gluconate consistently contained the lowest amounts of Cd. Because Cd is a non-essential potentially toxic element for humans, its concentration in nutritional supplements should be minimized and possibly regulated by government-established standards. C1 Inst Appl Res, Palmerston North, New Zealand. Pacific NW Natl Lab, Adv Inorgan Anal Grp, Richland, WA 99352 USA. Univ Washington, Seattle, WA 98195 USA. RP Krone, CA (reprint author), Inst Appl Res, POB 1925, Palmerston North, New Zealand. NR 13 TC 15 Z9 17 U1 1 U2 6 PU CARFAX PUBLISHING PI BASINGSTOKE PA RANKINE RD, BASINGSTOKE RG24 8PR, HANTS, ENGLAND SN 0963-7486 J9 INT J FOOD SCI NUTR JI Int. J. Food Sci. Nutr. PD JUL PY 2001 VL 52 IS 4 BP 379 EP 382 PG 4 WC Food Science & Technology; Nutrition & Dietetics SC Food Science & Technology; Nutrition & Dietetics GA 451VJ UT WOS:000169822800010 PM 11474903 ER PT J AU Martens, SN Breshears, DD Barnes, FJ AF Martens, SN Breshears, DD Barnes, FJ TI Development of species dominance along an elevational gradient: Population dynamics of Pinus edulis and Juniperus monosperma SO INTERNATIONAL JOURNAL OF PLANT SCIENCES LA English DT Article DE canonical correspondence analysis; pinon-juniper woodland; plant mortality ID NORTHERN NEW-MEXICO; SPATIAL-PATTERN; PLANT-COMMUNITIES; GREAT-BASIN; GRASSLAND/FOREST CONTINUUM; ENVIRONMENTAL GRADIENT; SUMMER PRECIPITATION; PATAGONIAN STEPPE; DROUGHT TOLERANCE; DIFFERENTIAL USE AB We evaluated species-environment relationships within pinon-juniper woodlands in northern New Mexico (United States) using canonical correspondence analysis (CCA). The first CCA axis was associated primarily with elevation. Our results showed separation between pinon and juniper along the elevation gradient, as expected: pinon is relatively more dominant at higher sites, whereas juniper is relatively more dominant at lower sites. To examine how this pattern of dominance might emerge with time, we plotted the position of centroids for three pinon and juniper size classes along the first CCA axis. We found that small pinons and junipers were distributed relatively uniformly across the gradient, whereas large pinons and junipers were strongly segregated along the gradient, with intermediate-sized pinons and junipers intermediate on the CCA axis between small and large. This produced a pattern of increased divergence between the two species that increased with size. We suggest that this pattern emerges as a result of differential mortality between the species rather than as a result of differences in seedling establishment along the gradient. These differences between the species could result from differences in resource use (i.e., physiology) and resource acquisition (i.e., rooting patterns relative to plant available water). We present a conceptual model of how differences between the species in resource acquisition increase with size (age). We suggest that differences in resource acquisition between species, which increase as individuals mature, may play a greater role in determining species dominance along resource gradients than has been previously appreciated. C1 Los Alamos Natl Lab, Div Earth & Environm Sci, Environm Dynam & Spatial Anal Grp, Los Alamos, NM 87545 USA. RP Breshears, DD (reprint author), Los Alamos Natl Lab, Div Earth & Environm Sci, Environm Dynam & Spatial Anal Grp, Mail Stop J495, Los Alamos, NM 87545 USA. EM daveb@lanl.gov RI Breshears, David/B-9318-2009 OI Breshears, David/0000-0001-6601-0058 NR 72 TC 18 Z9 18 U1 2 U2 10 PU UNIV CHICAGO PRESS PI CHICAGO PA 1427 E 60TH ST, CHICAGO, IL 60637-2954 USA SN 1058-5893 J9 INT J PLANT SCI JI Int. J. Plant Sci. PD JUL PY 2001 VL 162 IS 4 BP 777 EP 783 DI 10.1086/320772 PG 7 WC Plant Sciences SC Plant Sciences GA 439CZ UT WOS:000169094400008 ER PT J AU Wu, H Durante, M Lucas, JN AF Wu, H Durante, M Lucas, JN TI Relationship between radiation-induced aberrations in individual chromosomes and their DNA content: effects of interaction distance SO INTERNATIONAL JOURNAL OF RADIATION BIOLOGY LA English DT Article ID IN-SITU HYBRIDIZATION; INDUCED STRUCTURAL-ABERRATIONS; IONIZING-RADIATION; INTERPHASE; FREQUENCY; INVOLVEMENT; LYMPHOCYTES; EXPOSURE; GEOMETRY; DOMAINS AB Purpose: To study the effect of the interaction distance on the frequency of inter- and intrachromosome exchanges in individual chromosomes with respect to their DNA content. Assumptions: Chromosome exchanges are formed by misrejoining of tw DNA double-strand breaks (DSB) induced within an interaction distance, d. It is assumed that chromosomes in G(o)/G(1) phase of the cell cycle occupy a spherical domain in a cell nucleus, with no spatial overlap between individual chromosome domains. Results: Formulae are derived for the probability of formation of inter-, as well as intra-, chromosome exchanges relating to the DNA content of the chromosome for a given interaction distance. For interaction distances <1 m, the relative frequency of interchromosome exchanges predicted by the present model is similar to that by Cigarran et al. (1998) based of the assumption that the probability of interchromosome exchanges is proportional to the 'surface area' of the chromosome territory. The 'surface area' assumption is shown to be a limiting case of d-->0 in the present model. The present model also predicts that the probability of intrachromosome exchanges occurring in individual chromosomes is proportional to their DNA content with correction terms. Conclusion: When the interaction distance is small, the 'surface area' distribution for chromosome participation in interchromosome exchanges has been expected. However, the present model shows that for the interaction distance as large as 1 mum, the predicted probability of interchromosome exchange formation is still close to the surface area distribution. Therefore, this distribution does not necessarily rule out the formation of complex chromosomal aberrations by long-range misrejoining of DSB. C1 NASA, Lyndon B Johnson Space Ctr, Radiat Biophys Lab, Houston, TX 77058 USA. NASA, Lyndon B Johnson Space Ctr, Kelsey Seybold Clin, Houston, TX 77058 USA. Univ Naples, Dept Phys, Naples, Italy. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Wu, H (reprint author), NASA, Lyndon B Johnson Space Ctr, Radiat Biophys Lab, Mail Code SD23, Houston, TX 77058 USA. RI Durante, Marco/K-1315-2014; OI Durante, Marco/0000-0002-4615-553X NR 23 TC 14 Z9 14 U1 1 U2 3 PU TAYLOR & FRANCIS LTD PI LONDON PA 11 NEW FETTER LANE, LONDON EC4P 4EE, ENGLAND SN 0955-3002 J9 INT J RADIAT BIOL JI Int. J. Radiat. Biol. PD JUL PY 2001 VL 77 IS 7 BP 781 EP 786 PG 6 WC Biology; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Life Sciences & Biomedicine - Other Topics; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 450PE UT WOS:000169751700003 PM 11454278 ER PT J AU He, H Deng, W Cassel, MJ Lucas, JN AF He, H Deng, W Cassel, MJ Lucas, JN TI Fluorescence in situ hybridization of metaphase chromosomes in suspension SO INTERNATIONAL JOURNAL OF RADIATION BIOLOGY LA English DT Article ID IN-SITU; FLOW-CYTOMETRY; DNA; LEUKEMIA AB Purpose: To describe a new method for FISH analysis of metaphase chromosome sin suspension. Materials and methods: Metaphase chromosomes in suspension were isolated from a Chinese hamster x human hybrid cell line. 314-2(1) Y, and a human cell line, GM 130B. During suspension hybridization, specific chromosomes were labeled from these two cell lines using either biotin-labeled human genomic DNA, a directly labeled human pancentromere DNA probe or a chromosome #1 locus-specific probe. Results The method allows, for the first time, recover of large numbers of isolated individual hybridized chromosomes with good morphology for both human x hamster hybrid and human cell lines. The results showed that 46 73% of the starting number of total chromosomes can be recovered after a FISH in suspension procedure. The well-preserved morphology of hybridized metaphase chromosomes allowed (1) rapid detection of individual human and hamster chromosome aberrations, (2) rapid counting of the painted human chromosomes and (3) fast, clear detection of chromosome region-specific probes. This method offers a new tool to assay chromosomes and DNA: it offers the possibility to develop new techniques for sorting chromosomes based on FISH signals, for early detection and screening of genetic diseases and for bulk measurement of both balanced or unbalanced chromosomal exchanges and rearrangements. Conclusion: The potential of the method described should facilitate fast, sensitive population monitoring, and increase sensitivity of the measurements in chromosome-based biodosimetry. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Aamer Lab Technol Inc, Arlington, VA 22201 USA. Sichuan Inst Occupat Hlth, Sichuan Inst Radiat Hlth & Protect, Chengdu 610041, Peoples R China. RP Lucas, JN (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808, Livermore, CA 94551 USA. NR 16 TC 3 Z9 3 U1 0 U2 0 PU TAYLOR & FRANCIS LTD PI LONDON PA 11 NEW FETTER LANE, LONDON EC4P 4EE, ENGLAND SN 0955-3002 J9 INT J RADIAT BIOL JI Int. J. Radiat. Biol. PD JUL PY 2001 VL 77 IS 7 BP 787 EP 795 PG 9 WC Biology; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Life Sciences & Biomedicine - Other Topics; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 450PE UT WOS:000169751700004 PM 11454279 ER PT J AU Hsieh, WA Lucas, JN Hwang, JJ Chan, CC Chang, WP AF Hsieh, WA Lucas, JN Hwang, JJ Chan, CC Chang, WP TI Biodosimetry using chromosomal translocations measured by FISH in a population chronically exposed to low dose-rate Co-60 gamma-irradiation SO INTERNATIONAL JOURNAL OF RADIATION BIOLOGY LA English DT Article ID IN-SITU HYBRIDIZATION; IONIZING-RADIATION; BIOLOGICAL DOSIMETRY; SYMMETRICAL TRANSLOCATIONS; CLEANUP WORKERS; LYMPHOCYTES; ABERRATIONS; BUILDINGS; FREQUENCY; TEMPERATURE AB Purpose: To evaluate the cumulative gamma -radiation personal exposure by analysing lymphocyte chromosome translocations using FISH painting and to compare FISH-derived biodoses with those derived from retrospective physical dose reconstruction in residents receiving chronic low dose-rate gamma -irradiation while living in radio-contaminated buildings. Materials and methods: Chromosome translocation frequencies were evaluated by scoring 933 3077 metaphases under fluorescence microscope for each of the five male and four female exposed individuals after they had relocated from the radioactive environment for 34 and 82 months. FISH painting was conducted using kits of whole-chromosome probes for chromosomes 1, 2 and 4 in orange and 3, 5 and 6 in green and counter-stained with 4',6-diamidino-2-phenylindole (DAPI). The retrospective dose estimation termed Taiwan Cumulative Dose (TCD) was conducted by assessment using detailed information of historical exposure and the environmental radioactivity for each apartment during previous residency. Results: A total of 20 244 well-prepared metaphases were scored. Biodoses were calculated from the translocation frequencies and physical doses were estimated from detail questionnaires for each individual. The translocation frequencies measured ranged from 2.2 x 10(-3) to 26.8 x 10(-)3 translocations per cell and the dose equivalent from 52.2 to 992.2 mSv. A good correlation was observed between the physical and biodoses. A plot of TCD against FISH-derived doses produced D-fish = 0.65 D-rCD, when fitted by a linear model, and D-fish = 0.53 D-rCD + 1.26 x 10(-4) D-TCD(2), when fitted with a linear quadratic model. Given the scatter in the data and the extremely small quadratic dose contribution, neither model could be ruled out. Conclusion: Chromosome translocations provide a valid method of dose estimation in extremely protracted low dose-rate gamma -radiation exposure. Validation of the TCD method by FISH-measured translocations supports the use of TCD for epidemiological studies. C1 Natl Yang Ming Univ, Sch Med, Inst Environm Hlth Sci, Taipei 112, Taiwan. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA USA. Natl Yang Ming Univ, Inst Radiol Sci, Taipei 112, Taiwan. Natl Taiwan Univ, Coll Publ Hlth, Inst Occupat Med & Ind Hyg, Taipei, Taiwan. Taipei Jen Ai Municipal Hosp, Dept Family Med, Taipei, Taiwan. RP Chang, WP (reprint author), Natl Yang Ming Univ, Sch Med, Inst Environm Hlth Sci, 155,Sect 2,Lih Non St, Taipei 112, Taiwan. OI CHAN, CHANG-CHUAN/0000-0002-7518-5236 NR 38 TC 19 Z9 22 U1 0 U2 3 PU TAYLOR & FRANCIS LTD PI LONDON PA 11 NEW FETTER LANE, LONDON EC4P 4EE, ENGLAND SN 0955-3002 J9 INT J RADIAT BIOL JI Int. J. Radiat. Biol. PD JUL PY 2001 VL 77 IS 7 BP 797 EP 804 PG 8 WC Biology; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Life Sciences & Biomedicine - Other Topics; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 450PE UT WOS:000169751700005 PM 11454280 ER PT J AU Takai, K Moser, DP Onstott, TC Spoelstra, N Pfiffner, SM Dohnalkova, A Fredrickson, JK AF Takai, K Moser, DP Onstott, TC Spoelstra, N Pfiffner, SM Dohnalkova, A Fredrickson, JK TI Alkaliphilus transvaalensis gen. nov., sp nov., an extremely alkaliphilic bacterium isolated from a deep South African gold mine SO INTERNATIONAL JOURNAL OF SYSTEMATIC AND EVOLUTIONARY MICROBIOLOGY LA English DT Article DE Alkaliphilus transvaalensis gen. nov.; sp nov.; alkaliphile; anaerobic; deep subsurface; gold mine ID SEA HYDROTHERMAL VENT; CONTINENTAL OIL-RESERVOIR; THERMOPHILIC BACTERIUM; DISSIMILATORY REDUCTION; PHYLOGENETIC DIVERSITY; PETROLEUM RESERVOIRS; REDUCING BACTERIUM; MICROBIAL ECOLOGY; SUBSURFACE; CLOSTRIDIUM AB A novel extreme alkaliphile was isolated from a mine water containment dam at 3.2 km bellow land surface in an ultra-deep gold mine near Carletonville, South Africa. The cells of this bacterium were straight to slightly curved rods, motile by flagella and formed endospores, Growth was observed over the temperature range 20-50 degreesC (optimum 40 degreesC; 45 min doubling time) and ph range 8.5-12.5 (optimum pH 10.0). The novel isolate, one of the most alkaliphilic micro-organisms yet described, was a strictly anaerobic chemo-organotroph capable of utilizing proteinaceous substrates such as yeast extract, peptone. tryptone and casein, Elemental sulfur, thiosulfate or fumarate, when included as accessory electron acceptors, improved growth. The G+C content of genomic DNA was 36.4 mol%, Phylogenetic analysis based on the 16S rDNA sequence indicated that the isolate is a member of cluster XI within the low G+C Cram-positive bacteria, but only distantly related to previously described members. On the basis of physiological and molecular properties, the isolate represents a novel species, for which the name Alkaliphilus transvaalensis gen. nov., sp. nov. is proposed (type strain SAGM1(T) = JCM 10712(T) = ATCC 700919(T), The mechanism of generation of the highly alkaline microbial habitat and the possible source of the alkaliphile are discussed. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. Princeton Univ, Dept Geosci, Princeton, NJ 08544 USA. Driefontein Consolidated Min Co, Carletonville, South Africa. Univ Tennessee, Ctr Environm Biotechnol, Oak Ridge, TN 37831 USA. RP Fredrickson, JK (reprint author), Pacific NW Natl Lab, POB 999, Richland, WA 99352 USA. NR 63 TC 79 Z9 84 U1 2 U2 23 PU SOC GENERAL MICROBIOLOGY PI READING PA MARLBOROUGH HOUSE, BASINGSTOKE RD, SPENCERS WOODS, READING RG7 1AE, BERKS, ENGLAND SN 1466-5026 J9 INT J SYST EVOL MICR JI Int. J. Syst. Evol. Microbiol. PD JUL PY 2001 VL 51 BP 1245 EP 1256 PN 4 PG 12 WC Microbiology SC Microbiology GA 454HE UT WOS:000169966500002 PM 11491320 ER PT J AU Jones, RH AF Jones, RH TI Advancing our understanding of localized corrosion SO JOM-JOURNAL OF THE MINERALS METALS & MATERIALS SOCIETY LA English DT Editorial Material C1 TMS Struct Mat Div, Corros & Environm Effects Comm, Warrendale, PA USA. RP Jones, RH (reprint author), Pacific NW Natl Lab, Richland, WA 99352 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086 USA SN 1047-4838 J9 JOM-J MIN MET MAT S JI JOM-J. Miner. Met. Mater. Soc. PD JUL PY 2001 VL 53 IS 7 BP 28 EP 28 DI 10.1007/s11837-001-0083-y PG 1 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Mineralogy; Mining & Mineral Processing SC Materials Science; Metallurgy & Metallurgical Engineering; Mineralogy; Mining & Mineral Processing GA 453RX UT WOS:000169931200006 ER PT J AU Missert, N Barbour, JC Copeland, RG Mikkalson, JE AF Missert, N Barbour, JC Copeland, RG Mikkalson, JE TI The localized corrosion of Al at engineered Cu islands SO JOM-JOURNAL OF THE MINERALS METALS & MATERIALS SOCIETY LA English DT Article ID ATOMIC-FORCE MICROSCOPY; ALUMINUM-ALLOYS; FLUORESCENCE MICROSCOPY; AL2CUMG; COPPER; DISSOLUTION; INITIATION AB Arrays of engineered copper islands on an aluminum thin-film matrix have been employed to investigate the role of copper in localized corrosion of Al-Cu alloys. When exposed to dilute NaCl solutions, the engineered samples corrode with a morphology similar to that observed in second-phase particles in real alloys. In-situ fluorescence microscopy allows the observation of oxygen reduction at copper islands during corrosion of the underlying aluminum thin-film matrix. The spacing between engineered copper islands was found to strongly influence the corrosion rate of the surrounding matrix. C1 Sandia Natl Labs, Dept Nanostruct & Semicond Phys, Albuquerque, NM 87185 USA. RP Missert, N (reprint author), Sandia Natl Labs, Dept Nanostruct & Semicond Phys, MS 1415,POB 5800, Albuquerque, NM 87185 USA. NR 21 TC 6 Z9 6 U1 1 U2 4 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086 USA SN 1047-4838 J9 JOM-J MIN MET MAT S JI JOM-J. Miner. Met. Mater. Soc. PD JUL PY 2001 VL 53 IS 7 BP 34 EP 36 DI 10.1007/s11837-001-0085-9 PG 3 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Mineralogy; Mining & Mineral Processing SC Materials Science; Metallurgy & Metallurgical Engineering; Mineralogy; Mining & Mineral Processing GA 453RX UT WOS:000169931200008 ER PT J AU Windisch, CF Baer, DR Engelhard, MH Jones, RH AF Windisch, CF Baer, DR Engelhard, MH Jones, RH TI Analyzing localized corrosion in ion-implanted metals via XPS/AES SO JOM-JOURNAL OF THE MINERALS METALS & MATERIALS SOCIETY LA English DT Article ID INTERGRANULAR STRESS-CORROSION; GRAIN-BOUNDARY CHEMISTRY; CALCIUM NITRATE; IRON-ALLOYS; PURE IRON; CRACKS; PHOSPHORUS; BEHAVIOR; STEELS; MG AB A combined electrochemical/surface analysis approach coupled with the use of ion-implanted samples has bern successfully used to study anodic processes relevant to intergranular stress corrosion cracking (IGSCC). Interpretation of the data and applying it to an understanding of IGSCC varies in complexity and difficulty with the system under study. In some cases, there is a direct correspondence between composition and corrosion rates while, in others, the chemistry is more complex and secondary processes become dominant under some conditions. Nevertheless, the use of this approach has proved valuable, at the very least providing a qualitative understanding of the interplay between oxidation of a metal and the chemistry of segregants ar grain boundaries that has forwarded modeling efforts on IGSCC. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Windisch, CF (reprint author), Pacific NW Natl Lab, MS k2-44,Box 999, Richland, WA 99352 USA. RI Engelhard, Mark/F-1317-2010; Baer, Donald/J-6191-2013; OI Baer, Donald/0000-0003-0875-5961; Engelhard, Mark/0000-0002-5543-0812 NR 33 TC 1 Z9 1 U1 0 U2 1 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 184 THORN HILL RD, WARRENDALE, PA 15086 USA SN 1047-4838 J9 JOM-J MIN MET MAT S JI JOM-J. Miner. Met. Mater. Soc. PD JUL PY 2001 VL 53 IS 7 BP 37 EP 41 DI 10.1007/s11837-001-0086-8 PG 5 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Mineralogy; Mining & Mineral Processing SC Materials Science; Metallurgy & Metallurgical Engineering; Mineralogy; Mining & Mineral Processing GA 453RX UT WOS:000169931200009 ER PT J AU Dunn, J Osterheld, AL Nilsen, J Hunter, JR Li, YL Faenov, AY Pikuz, TA Shlyaptsev, VN AF Dunn, J Osterheld, AL Nilsen, J Hunter, JR Li, YL Faenov, AY Pikuz, TA Shlyaptsev, VN TI Saturated output tabletop X-ray lasers SO JOURNAL DE PHYSIQUE IV LA English DT Article; Proceedings Paper CT 7th International Conference on X-Ray Lasers CY JUN 19-23, 2000 CL ST MALO, FRANCE SP Soc Francaise Phys, Soc Francaise Opt, Thomson CSF Lasers, Roper Sci (Princeton Instruments) ID TRANSIENT GAIN; NM; TITANIUM; PULSE AB The high efficiency method of transient collisional excitation has been successfully demonstrated for Ne-like and Ni-like ion x-ray laser schemes with small 5 - 10 J laser facilities. Our recent studies using the tabletop COMET (Compact Multipulse Terawatt) laser system at the Lawrence Livermore National Laboratory (LLNL) have produced several x-ray lasers operating in the saturation regime. Output energy of 10 - 15 muJ corresponding to a gL product of 18 has been achieved on the Ni-like Pd 4d --> 4p transition at 147 Angstrom with a total energy of 5 - 7 J in a 600 ps pulse followed by a 1.2 ps pulse. Analysis of the laser beam angular profile indicates that refraction plays an important role in the amplification and propagation process in the plasma column. We report further improvement in the extraction efficiency by varying a number of laser driver parameters. In particular, the duration of the second short pulse producing the inversion has an observed effect on the x-ray laser output. C1 Lawrence Livermore Natl Lab, ILSA, Livermore, CA 94550 USA. VNIIFTRI, MISDC, Mendeleyevsk 141570, Moscow Region, Russia. Univ Calif Davis, DAS, Livermore, CA 94550 USA. RP Dunn, J (reprint author), Lawrence Livermore Natl Lab, ILSA, Livermore, CA 94550 USA. NR 24 TC 5 Z9 5 U1 0 U2 0 PU E D P SCIENCES PI LES ULIS CEDEXA PA 7, AVE DU HOGGAR, PARC D ACTIVITES COURTABOEUF, BP 112, F-91944 LES ULIS CEDEXA, FRANCE SN 1155-4339 J9 J PHYS IV JI J. Phys. IV PD JUL PY 2001 VL 11 IS PR2 BP 19 EP 26 DI 10.1051/jp4:2001203 PG 8 WC Physics, Multidisciplinary SC Physics GA 476CK UT WOS:000171208500005 ER PT J AU Dunn, J Faenov, AY Pikuz, TA Osterheld, AL Moon, SJ Fournier, KB Nilsen, J Skobelev, IY Magunov, AI Shlyaptsev, VN AF Dunn, J Faenov, AY Pikuz, TA Osterheld, AL Moon, SJ Fournier, KB Nilsen, J Skobelev, IY Magunov, AI Shlyaptsev, VN TI Spectral and imaging characterization of tabletop X-ray lasers SO JOURNAL DE PHYSIQUE IV LA English DT Article; Proceedings Paper CT 7th International Conference on X-Ray Lasers CY JUN 19-23, 2000 CL ST MALO, FRANCE SP Soc Francaise Phys, Soc Francaise Opt, Thomson CSF Lasers, Roper Sci (Princeton Instruments) ID TRANSIENT GAIN AB We have performed L-shell spectroscopy and one-dimensional (I-D) imaging of a line focus plasma from a laser-heated Fe polished stab using the tabletop COMET laser system at the Lawrence Livermore National Laboratory. These plasmas are used to generate a Ne-like Fe transient gain x-ray laser that is recorded simultaneously. A spherically-curved crystal spectrometer gives high resolution x-ray spectra of the n= 3 - 2 and n= 4 - 2 resonance lines with I-D spatial resolution along the line focus. Spectra are presented for different laser pulse conditions. In addition, a variety of x-ray imaging techniques are described. We discuss imaging results from a double-slit x-ray camera with a spherically-curved crystal spectrometer. We show a high resolution Fe K-alpha spectrum from the x-ray laser target that indicates the presence of hot electrons in the x-ray laser plasma. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. VNIIFTRI, MISDC, Mendeleyevsk 141570, Moscow Region, Russia. Univ Calif Davis, DAS, Livermore, CA 94550 USA. RP Dunn, J (reprint author), Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 14 TC 0 Z9 0 U1 0 U2 0 PU E D P SCIENCES PI LES ULIS CEDEXA PA 7, AVE DU HOGGAR, PARC D ACTIVITES COURTABOEUF, BP 112, F-91944 LES ULIS CEDEXA, FRANCE SN 1155-4339 J9 J PHYS IV JI J. Phys. IV PD JUL PY 2001 VL 11 IS PR2 BP 51 EP 54 DI 10.1051/jp4:2001209 PG 4 WC Physics, Multidisciplinary SC Physics GA 476CK UT WOS:000171208500011 ER PT J AU Nilsen, J Li, YL Dunn, J Barbee, TW Osterheld, AL AF Nilsen, J Li, YL Dunn, J Barbee, TW Osterheld, AL TI Modeling and demonstration of a saturated Ni-like Mo X-ray laser SO JOURNAL DE PHYSIQUE IV LA English DT Article; Proceedings Paper CT 7th International Conference on X-Ray Lasers CY JUN 19-23, 2000 CL ST MALO, FRANCE SP Soc Francaise Phys, Soc Francaise Opt, Thomson CSF Lasers, Roper Sci (Princeton Instruments) ID TRANSIENT GAIN; TITANIUM; NM AB The technique of using a nsec pulse to preform and ionize the plasma followed by a psec pulse to heat the plasma has enabled us to achieve saturated laser output for low-Z neon-like and nickel-like ions driven by small lasers with less than ten joules of energy. In this work we present and model recent experiments done using the COMET laser at Lawrence Livermore National Laboratory to illuminate slab targets of Mo up to I cm long with a one joule, 600 ps prepulse followed 700 psec later by a five joule, one psec drive pulse. The experiments demonstrate saturated output on the Ni-like Mo 3d(9) 4d S-1(0) --> 3d(9) 4p P-1(1) laser line at 18.9 nm. The small signal gain and gain length product are estimated by measuring the laser output versus target length. Experiments are done using multilayer mirrors to obtain two-dimensional images of the output aperture of the laser and to measure the total laser energy as a function of various parameters such as the delay between the short and long pulses and the energy of the two pulses. To model the experiments the LASNEX code is used to calculate the hydrodynamic evolution of the plasma and provide the temperatures and densities to the XRASER code, which then does the kinetics calculations to determine the gain. The temporal and spatial evolution of the plasma is studied both with and without radiation transport included for the 4f and 4p --> 3d Ni-like Mo resonance lines, High gains are predicted for both the 3d(9) 4d S-1(0) --> 3d(9) 4p P-1(1) laser line at 18.9nm and the 3d(9) 4f P-1(1) --> 3d(9) 4d P-1(1) photopumped line which is observed to laser at 22.6 nm. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Nilsen, J (reprint author), Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 8 TC 1 Z9 1 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 1155-4339 J9 J PHYS IV JI J. Phys. IV PD JUL PY 2001 VL 11 IS PR2 BP 67 EP 73 DI 10.1051/jp4:2001212 PG 7 WC Physics, Multidisciplinary SC Physics GA 476CK UT WOS:000171208500014 ER PT J AU Liu, YW Seminario, M Tomasel, FG Chang, C Rocca, JJ Attwood, DT AF Liu, YW Seminario, M Tomasel, FG Chang, C Rocca, JJ Attwood, DT TI Spatial coherence measurement of a high average power table-top soft X-ray laser SO JOURNAL DE PHYSIQUE IV LA English DT Article; Proceedings Paper CT 7th International Conference on X-Ray Lasers CY JUN 19-23, 2000 CL ST MALO, FRANCE SP Soc Francaise Phys, Soc Francaise Opt, Thomson CSF Lasers, Roper Sci (Princeton Instruments) ID GENERATION; AMPLIFIER AB An extraordinarily high degree of spatial coherence from a high average power, tabletop 46.9 nm laser was observed in two-pinhole interference experiments. Refractive anti-guiding and gain guiding along a capillary discharge-produced plasma column causes a rapid increase of the spatial coherence with amplifier length. Full spatial coherence was approached with a 36 cm long plasma of very high axial uniformity and a length to diameter ratio exceeding 1000:1. C1 Univ Calif Berkeley, Appl Sci & Technol Grad Program, Berkeley, CA 94720 USA. Colorado State Univ, Dept Elect & Comp Engn, Ft Collins, CO 80523 USA. Univ Calif Berkeley, Dept Elect Engn & Comp Sci, Berkeley, CA 94720 USA. Lawrence Berkeley Natl Lab, Ctr Xray Opt, Berkeley, CA USA. RP Liu, YW (reprint author), Univ Calif Berkeley, Appl Sci & Technol Grad Program, Berkeley, CA 94720 USA. NR 21 TC 10 Z9 10 U1 0 U2 0 PU E D P SCIENCES PI LES ULIS CEDEXA PA 7, AVE DU HOGGAR, PARC D ACTIVITES COURTABOEUF, BP 112, F-91944 LES ULIS CEDEXA, FRANCE SN 1155-4339 J9 J PHYS IV JI J. Phys. IV PD JUL PY 2001 VL 11 IS PR2 BP 123 EP 126 DI 10.1051/jp4:2001224 PG 4 WC Physics, Multidisciplinary SC Physics GA 476CK UT WOS:000171208500026 ER PT J AU Smith, R Key, MH AF Smith, R Key, MH TI A review of laser and synchrotron based X-ray sources SO JOURNAL DE PHYSIQUE IV LA English DT Article; Proceedings Paper CT 7th International Conference on X-Ray Lasers CY JUN 19-23, 2000 CL ST MALO, FRANCE SP Soc Francaise Phys, Soc Francaise Opt, Thomson CSF Lasers, Roper Sci (Princeton Instruments) ID ORDER HARMONIC-GENERATION; CAPILLARY DISCHARGE; PULSE INTERACTIONS; HOT-ELECTRONS; SOLID TARGETS; XUV LASER; PLASMA; RADIATION; NM; DYNAMICS AB The rapid development of laser technology and related progress in research using lasers is shifting the boundaries where laser based sources are preferred over other light sources particularly in the XUV and x-ray spectral region. Laser based sources have exceptional capability for short pulse and high brightness and with improvements in high repetition rate pulsed operation, such sources are also becoming more interesting for their average power capability. This study presents an evaluation of the current capabilities and near term future potential of laser based light sources and summarises, for the purpose of comparison, the characteristics and near term prospects of sources based on synchrotron radiation and free electron lasers. Relative comparisons are given within charts of peak brightness. C1 Univ Paris Sud, LSAI, F-91405 Orsay, France. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Smith, R (reprint author), Univ Paris Sud, LSAI, Batiment 350, F-91405 Orsay, France. NR 46 TC 2 Z9 2 U1 3 U2 6 PU E D P SCIENCES PI LES ULIS CEDEXA PA 7, AVE DU HOGGAR, PARC D ACTIVITES COURTABOEUF, BP 112, F-91944 LES ULIS CEDEXA, FRANCE SN 1155-4339 J9 J PHYS IV JI J. Phys. IV PD JUL PY 2001 VL 11 IS PR2 BP 383 EP 388 DI 10.1051/jp4:2001274 PG 6 WC Physics, Multidisciplinary SC Physics GA 476CK UT WOS:000171208500076 ER PT J AU Attwood, DT AF Attwood, DT TI Applications of short wavelength radiation: Soft X-ray microscopy and EUV lithography SO JOURNAL DE PHYSIQUE IV LA English DT Article; Proceedings Paper CT 7th International Conference on X-Ray Lasers CY JUN 19-23, 2000 CL ST MALO, FRANCE SP Soc Francaise Phys, Soc Francaise Opt, Thomson CSF Lasers, Roper Sci (Princeton Instruments) ID ULTRAVIOLET AB Short wavelength radiation, in the 1-20 run wavelength range is discussed, with particular emphasis on applications to soft x-ray (SXR) microscopy and extreme ultraviolet (EUV) radiation. In this paper we bring attention to the fact that these two applications require a wide variety of SXR/EUV sources, some with good spatial coherence, others largely incoherent; some at fairly high average power (tens of watts), others at rather low (microwatts) power; some at fixed wavelength, others tunable. These provide great opportunities for attendees of this workshop who represent the world's body of knowledge in this area. We give reference to recent papers to illustrate these points, and call attention to recurring publications where further opportunities and progress can be monitored. C1 Univ Calif Berkeley, Appl Sci & Technol Grad Grp, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Xray Opt, Berkeley, CA 94720 USA. RP Attwood, DT (reprint author), Univ Calif Berkeley, Appl Sci & Technol Grad Grp, Berkeley, CA 94720 USA. NR 15 TC 2 Z9 2 U1 0 U2 0 PU E D P SCIENCES PI LES ULIS CEDEXA PA 7, AVE DU HOGGAR, PARC D ACTIVITES COURTABOEUF, BP 112, F-91944 LES ULIS CEDEXA, FRANCE SN 1155-4339 J9 J PHYS IV JI J. Phys. IV PD JUL PY 2001 VL 11 IS PR2 BP 443 EP 449 DI 10.1051/jp4:2001286 PG 7 WC Physics, Multidisciplinary SC Physics GA 476CK UT WOS:000171208500088 ER PT J AU Baldis, HA Dunn, J Foord, ME Rozmus, W Andersen, C Shepherd, R AF Baldis, HA Dunn, J Foord, ME Rozmus, W Andersen, C Shepherd, R TI New regime of Thomson scattering: Probing dense plasmas with X-ray lasers SO JOURNAL DE PHYSIQUE IV LA English DT Article; Proceedings Paper CT 7th International Conference on X-Ray Lasers CY JUN 19-23, 2000 CL ST MALO, FRANCE SP Soc Francaise Phys, Soc Francaise Opt, Thomson CSF Lasers, Roper Sci (Princeton Instruments) ID ION-ACOUSTIC-WAVES; DIFFRACTION; SATURATION; NM AB In this paper we demonstrate through calculations and theoretical analysis the first application of a x-ray laser for probing hot, high-density plasmas (n(e) : greater than or equal to 10(23) cm(-3)) using a Ni-like transient collisional excitation x-ray laser as a probe. Theoretical predictions are used to diagnose the electron temperature in short pulse (500 fs) laser produced plasmas. The threshold power of the x-ray probe is estimated by comparing theoretical scattering levels with plasma thermal emission. The necessary spectral resolution of the instrument sufficient for resolving electron temperature is given. C1 Lawrence Livermore Natl Lab, Inst Laser Sci & Applicat, Livermore, CA 94550 USA. Univ Calif Davis, Dept Appl Sci, Davis, CA 95616 USA. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Alberta, Inst Theoret Phys, Dept Phys, Edmonton, AB T6G 2J1, Canada. RP Baldis, HA (reprint author), Lawrence Livermore Natl Lab, Inst Laser Sci & Applicat, POB 808, Livermore, CA 94550 USA. NR 19 TC 2 Z9 2 U1 1 U2 1 PU E D P SCIENCES PI LES ULIS CEDEXA PA 7, AVE DU HOGGAR, PARC D ACTIVITES COURTABOEUF, BP 112, F-91944 LES ULIS CEDEXA, FRANCE SN 1155-4339 J9 J PHYS IV JI J. Phys. IV PD JUL PY 2001 VL 11 IS PR2 BP 469 EP 472 DI 10.1051/jp4:2001289 PG 4 WC Physics, Multidisciplinary SC Physics GA 476CK UT WOS:000171208500091 ER PT J AU Wampler, WR Myers, SM Wright, AF Barbour, JC Seager, CH Han, J AF Wampler, WR Myers, SM Wright, AF Barbour, JC Seager, CH Han, J TI Lattice location of hydrogen in Mg doped GaN SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID CHEMICAL-VAPOR-DEPOSITION; LIGHT-INDUCED REACTIVATION; ELECTRON BEAM IRRADIATION; DEFECTS; SILICON; ACCEPTORS; MECHANISM; DOPANTS; GAAS AB We have used ion channeling to examine the lattice configuration of hydrogen in Mg doped wurtzite GaN grown by metal organic chemical vapor deposition. Hydrogen is introduced by exposure to hydrogen gas or electron cyclotron resonance plasmas and by ion implantation. A density functional approach including lattice relaxation was used to calculate total energies for various locations and charge states of hydrogen in the wurtzite Mg doped GaN lattice. Results of channeling measurements are compared with channeling simulations for hydrogen at lattice locations predicted by the density functional theory. (C) 2001 American Institute of Physics. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Wampler, WR (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. EM wrwampl@sandia.gov RI Schaff, William/B-5839-2009 NR 37 TC 9 Z9 9 U1 0 U2 4 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 JUL 1 PY 2001 VL 90 IS 1 BP 108 EP 117 DI 10.1063/1.1377609 PG 10 WC Physics, Applied SC Physics GA 443UY UT WOS:000169361100015 ER PT J AU Jiao, S Sumant, A Kirk, MA Gruen, DM Krauss, AR Auciello, O AF Jiao, S Sumant, A Kirk, MA Gruen, DM Krauss, AR Auciello, O TI Microstructure of ultrananocrystalline diamond films grown by microwave Ar-CH4 plasma chemical vapor deposition with or without added H-2 SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID NANOCRYSTALLINE DIAMOND; PRECURSORS; ADDITIONS; TEM AB Ultrananocrystalline diamond (UNCD) films, grown using microwave plasma-enhanced chemical vapor deposition with gas mixtures of Ar-1%CH4 or Ar-1%CH4-5%H-2, have been examined with transmission electron microscopy (TEM). The films consist of equiaxed nanograins (2-10 nm in diameter) and elongated twinned dendritic grains. The area occupied by dendritic grains increases with the addition of H-2. High resolution electron microscopy shows no evidence of an amorphous phase at grain boundaries, which are typically one or two atomic layer thick (0.2-0.4 nm). Cross-section TEM reveals a noncolumnar structure of the films. The initial nucleation of diamond occurs directly on the Si substrate when H-2 is present in the plasma. For the case of UNCD growth from a plasma without addition of H-2, the initial nucleation occurs on an amorphous carbon layer about 10-15 nm thick directly grown on the Si substrate. This result indicates that hydrogen plays a critical role in determining the nucleation interface between the UNCD films and the Si substrate. The relation between diamond nuclei and Si is primarily random and occasionally epitaxial. (C) 2001 American Institute of Physics. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Kirk, MA (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 13 TC 121 Z9 121 U1 2 U2 28 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD JUL 1 PY 2001 VL 90 IS 1 BP 118 EP 122 DI 10.1063/1.1377301 PG 5 WC Physics, Applied SC Physics GA 443UY UT WOS:000169361100016 ER PT J AU Hu, ZY Thundat, T Warmack, RJ AF Hu, ZY Thundat, T Warmack, RJ TI Investigation of adsorption and absorption-induced stresses using microcantilever sensors SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID ATOMIC-FORCE MICROSCOPY; INDUCED SURFACE STRESS; THIN AU FILMS; MERCURY ADSORPTION; GOLD; VAPOR AB The interaction between a vapor and a thin film adsorbed on one side of a bimaterial microcantilever produces differential stress, resulting in readily measurable curvatures of the cantilever structure. Depending upon the system studied, there exist two types of gas-solid interaction: bulk-like absorption and surface-like adsorption. The absorption of hydrogen into palladium results in film expansion whose magnitude is governed by hydrogen partial pressure. The bending of a bimaterial microcantilever (palladium/silicon) due to hydrogen absorption depends on the thickness of the palladium film and is reversible but rate limited by a surface barrier. In contrast, the stress induced by adsorption of mercury onto a bimaterial (gold/silicon) cantilever is irreversible at room temperature, is rate limited by surface coverage, and is independent of the gold-film thickness. (C) 2001 American Institute of Physics. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. RP Thundat, T (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RI Hu, Zhiyu/J-7742-2013 NR 37 TC 90 Z9 90 U1 0 U2 9 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD JUL 1 PY 2001 VL 90 IS 1 BP 427 EP 431 DI 10.1063/1.1378333 PG 5 WC Physics, Applied SC Physics GA 443UY UT WOS:000169361100065 ER PT J AU Su, YJ Thomsen, MF Borovsky, JE Elphic, RC Lawrence, DJ McComas, DJ AF Su, YJ Thomsen, MF Borovsky, JE Elphic, RC Lawrence, DJ McComas, DJ TI Plasmaspheric observations at geosynchronous orbit SO JOURNAL OF ATMOSPHERIC AND SOLAR-TERRESTRIAL PHYSICS LA English DT Article DE plasma circulation; plasmasphere refilling; the fate of plasmaspheric material ID MAGNETOSPHERIC PLASMA ANALYZER; OUTER PLASMASPHERE; ELECTRON-DENSITY; DUSKSIDE BULGE; BOUNDARY-LAYER; POLAR WIND; MODEL; DYNAMICS; MAGNETOPAUSE; CONVECTION AB The plasmasphere comprises the near-Earth region of the magnetosphere populated by dense, cold plasma of ionospheric origin. The plasmaspheric configuration changes size and shape according to the strength of the convection electric field, which is related to the level of geomagnetic activity. Under quiet conditions, magnetic flux tubes in the outer plasmasphere remain on closed drift paths for days, refilling with ionospheric plasma. We investigate the refilling of flux tubes on their first pass through the dayside region at geosynchronous orbit. The resulting plasmaspheric refilling rate is found to be similar to0.25-0.7 cm(-3) h(-1). which is comparable with earlier results. Moreover, the refilling rate during periods of increased geomagnetic activity (K-p greater than or equal to 4) is approximately twice the rate obtained at lower levels of geomagnetic activity (K-p less than or equal to 2). The refilling rate appears to be low in northern winter, however, a strong variation is not found for other three seasons. No strong indication of solar cycle dependence is found from the 3-year data set. When the magnetospheric convection increases, the magnetic flux tubes at the outer plasmasphere find themselves on open drift paths and the cold and dense plasmaspheric material is observed to drain toward the dayside magnetopause. We examine a set of events during times of strong magnetopause compression and erosion in which cold plasmaspheric ions are observed immediately adjacent to magnetosheath ions. The resulting evidence indicates that the draining plasmaspheric ions and entering magnetosheath ions are sometimes simultaneously present on the same flux tube. Moreover, in most of those cases, the detailed velocity-space signatures are consistent with expectations based on the reconnection process. Thus, the dense, cold plasma of the draining plasmasphere participates in the dayside magnetopause reconnection process. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. SW Res Inst, Instrumentat & Space Res Div, San Antonio, TX 78228 USA. RP Su, YJ (reprint author), Univ Colorado, LASPI, 1234 Innovat Dr, Boulder, CO 80303 USA. RI Lawrence, David/E-7463-2015 OI Lawrence, David/0000-0002-7696-6667 NR 46 TC 6 Z9 6 U1 0 U2 2 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1364-6826 J9 J ATMOS SOL-TERR PHY JI J. Atmos. Sol.-Terr. Phys. PD JUL PY 2001 VL 63 IS 11 BP 1185 EP 1197 DI 10.1016/S1364-6826(00)00221-2 PG 13 WC Geochemistry & Geophysics; Meteorology & Atmospheric Sciences SC Geochemistry & Geophysics; Meteorology & Atmospheric Sciences GA 451LE UT WOS:000169802900009 ER PT J AU Gosset, G Bonner, CA Jensen, RA AF Gosset, G Bonner, CA Jensen, RA TI Microbial origin of plant-type 2-keto-3-deoxy-D-arabino-heptulosonate 7-phosphate synthases, exemplified by the chorismate- and tryptophan-regulated enzyme from Xanthomonas campestris SO JOURNAL OF BACTERIOLOGY LA English DT Article ID 3-DEOXY-D-MANNO-OCTULOSONATE 8-PHOSPHATE SYNTHASE; 3-DEOXY-D-ARABINO-HEPTULOSONATE-7-PHOSPHATE SYNTHASE; ESCHERICHIA-COLI; 3-AMINO-5-HYDROXYBENZOIC ACID; AROMATIC BIOSYNTHESIS; FEEDBACK INHIBITION; MOLECULAR ANALYSIS; MC(7)N UNITS; GENE-CLUSTER; DS-MN AB Enzymes performing the initial reaction of aromatic amino acid biosynthesis, 2-keto-3-deoxy-D-arabino-heptulosonate 7-phosphate (DAHP) syntheses, exist as two distinct homology classes. The three classic Escherichia coli paralogs are AroA(I) proteins, but many members of the Bacteria possess the AroA(II) class of enzyme, sometimes in combination with AroA(I) proteins. AroA(II) DAHP syntheses until now have been shown to be specifically dedicated to secondary metabolism (e.g., formation of ansamycin antibiotics or phenazine pigment). In contrast, here we show that the Xanthomonas campestris AroA(II) protein functions as the sole DAHP synthase supporting aromatic amino acid biosynthesis. X. campestris AroA(II) was cloned in E. coli by functional complementation, and genes corresponding to two possible translation starts were expressed. We developed a 1-day partial purification method (> 99%) for the unstable protein. The recombinant AroA(II) protein was found to be subject to an allosteric pattern of sequential feedback inhibition in which chorismate is the prime allosteric effector. L-Tryptophan was found to be a minor feedback inhibitor. An N-terminal region of 111 amino acids may be located in the periplasm since a probable inner membrane-spanning region is predicted. Unlike chloroplast-localized AroA(II) of higher plants, X. campestris AroA(II) was not hysteretically activated by dithiols. Compared to plant AroA(II) proteins, differences in divalent metal activation were also observed. Phylogenetic tree analysis shows that AroA(II) originated within the Bacteria domain, and it seems probable that higher-plant plastids acquired AroA(II) from a gram-negative bacterium via endosymbiosis. The X. campestris AroA(II) protein is suggested to exemplify a case of analog displacement whereby an ancestral aroA(I) species was discarded, with the aroA(II) replacement providing an alternative pattern of allosteric control. Three subgroups of AroA,, proteins can be recognized: a large, central group containing the plant enzymes and that from X. campestris, one defined by a three-residue deletion near the conserved KPRS motif, and one possessing a larger deletion further downstream. C1 Univ Nacl Autonoma Mexico, Inst Biotecnol, Dept Mol Microbiol, Cuernavaca 62250, Morelos, Mexico. Univ Florida, Dept Microbiol & Cell Sci, Gainesville, FL 32611 USA. CUNY City Coll, Dept Chem, New York, NY 10031 USA. Los Alamos Natl Lab, Biosci Div, Los Alamos, NM 87544 USA. RP Univ Nacl Autonoma Mexico, Inst Biotecnol, Dept Mol Microbiol, Apdo Postal 510-3, Cuernavaca 62250, Morelos, Mexico. EM gosset@ibt.unam.mx OI Gosset, Guillermo/0000-0003-3127-0911 NR 36 TC 40 Z9 41 U1 0 U2 2 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1752 N ST NW, WASHINGTON, DC 20036-2904 USA SN 0021-9193 EI 1098-5530 J9 J BACTERIOL JI J. Bacteriol. PD JUL PY 2001 VL 183 IS 13 BP 4061 EP 4070 DI 10.1128/JB.183.13.4061-4070.2001 PG 10 WC Microbiology SC Microbiology GA 442DH UT WOS:000169269600029 PM 11395471 ER PT J AU Kim, BM Feit, MD Rubenchik, AM Joslin, EJ Celliers, PM Eichler, J Da Silva, LB AF Kim, BM Feit, MD Rubenchik, AM Joslin, EJ Celliers, PM Eichler, J Da Silva, LB TI Influence of pulse duration on ultrashort laser pulse ablation of biological tissues SO JOURNAL OF BIOMEDICAL OPTICS LA English DT Article DE ultrashort laser pulse; pulse duration; ablation; biological tissues ID INDUCED OPTICAL-BREAKDOWN; PICOSECOND LASER; SHOCK-WAVES; WATER; NANOSECOND; HARD; DIELECTRICS; DEPENDENCE; ABSORPTION; THRESHOLD AB Ablation characteristics of ultrashort laser pulses were investigated for pulse durations in the range of 130 fs-10 ps. Tissue samples used in the study were dental hard tissue (dentin) and water. We observed differences in ablation crater morphology for craters generated with pulse durations in the 130 fs-1 ps and the 5 ps-10 ps range. For the water experiment, the surface ablation and subsequent propagation of stress waves were monitored using Mach-Zehnder interferometry. For 130 fs-1 ps, energy is deposited on the surface while for longer pulses the beam penetrates into the sample. Both studies indicate that a transition occurs between 1 and 5 PS. (C) 2001 Society of Photo-Optical Instrumentation Engineers. C1 Yonsei Univ, Dept Biomed Engn, Wonju 220710, Kangwon Do, South Korea. Lawrence Livermore Natl Lab, Med Technol Program, Livermore, CA 94551 USA. Univ Appl Sci, Tech Fachhsch Berlin, D-13347 Berlin, Germany. RP Kim, BM (reprint author), Yonsei Univ, Dept Biomed Engn, 234 Maeji, Wonju 220710, Kangwon Do, South Korea. RI Feit, Michael/A-4480-2009 NR 23 TC 61 Z9 62 U1 2 U2 11 PU SPIE-INT SOCIETY OPTICAL ENGINEERING PI BELLINGHAM PA 1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98225 USA SN 1083-3668 J9 J BIOMED OPT JI J. Biomed. Opt. PD JUL PY 2001 VL 6 IS 3 BP 332 EP 338 DI 10.1117/1.1381561 PG 7 WC Biochemical Research Methods; Optics; Radiology, Nuclear Medicine & Medical Imaging SC Biochemistry & Molecular Biology; Optics; Radiology, Nuclear Medicine & Medical Imaging GA 462DR UT WOS:000170405900010 PM 11516324 ER PT J AU Monteiro, RS Zemlyanov, D Storey, JM Ribeiro, FH AF Monteiro, RS Zemlyanov, D Storey, JM Ribeiro, FH TI Surface area increase on Pd foils after oxidation in excess methane SO JOURNAL OF CATALYSIS LA English DT Article DE Pd foil; PdO morphology; methane combustion; O-18 isotope exchange; PdO surface area measurement ID SUPPORTED PALLADIUM CATALYSTS; COMBUSTION; PRETREATMENT; DYNAMICS; KINETICS; CARBON AB An increase in the PdO surface area by a factor of about 20 was observed after treatment of Pd foils in excess methane at 598 K. The surface area was increased as the O-2 partial pressure in the activation treatment was decreased. The activated foil was probed by the reaction of complete oxidation of methane in excess Oz. The rate was proportional to the PdO surface area and thus the turnover rate per unit of PdO area was the same as that for the untreated foil. Critical for this assessment was the determination of the PdO surface area measured by exchange of surface oxygen with O-18(2). The PdO surface area decreased after interaction with water when the sample was cooled. After treatment of the foil in excess methane, PdO but not Pd was identified by X-ray photoelectron spectroscopy, and carbon deposits from methane were identified on the surface and in the bulk by temperature-programmed desorption. (C) 2001 Academic Press. C1 Worcester Polytech Inst, Dept Chem Engn, Worcester, MA 01609 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Ribeiro, FH (reprint author), Worcester Polytech Inst, Dept Chem Engn, 100 Inst Rd, Worcester, MA 01609 USA. OI Monteiro, Robson/0000-0003-0818-7431; Ribeiro, Fabio/0000-0001-7752-461X NR 20 TC 28 Z9 29 U1 0 U2 12 PU ACADEMIC PRESS INC 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 JUL 1 PY 2001 VL 201 IS 1 BP 37 EP 45 DI 10.1006/jcat.2001.3235 PG 9 WC Chemistry, Physical; Engineering, Chemical SC Chemistry; Engineering GA 449UV UT WOS:000169706300004 ER PT J AU Dai, HJ Heath, KD Cochran, HD Simonson, JM AF Dai, HJ Heath, KD Cochran, HD Simonson, JM TI Density measurements of 2-propanol solutions in supercritical CO2 SO JOURNAL OF CHEMICAL AND ENGINEERING DATA LA English DT Article ID CARBON-DIOXIDE AB Using a vibrating-tube densitometer, densities of 2-propanol solutions with compositions between (0.72 and 1.89) mol % in supercritical CO2 have been measured isothermally at (40, 50, 60, and 70) degreesC at pressures to 34.47 MPa. These measurements span the temperature and pressure ranges of earlier neutron scattering studies of the supercritical CO2 fluids, and density data are needed to interpret the results. In addition, these results should aid in using supercritical CO2 for separation or processing with 2-propanol and for improving the broad database supporting supercritical fluid technologies in general. C1 Oak Ridge Natl Lab, Div Chem Technol, Oak Ridge, TN 37831 USA. Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. Univ Tennessee, Dept Chem Engn, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Cochran, HD (reprint author), Oak Ridge Natl Lab, Div Chem Technol, POB 2008, Oak Ridge, TN 37831 USA. NR 6 TC 2 Z9 3 U1 0 U2 4 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0021-9568 J9 J CHEM ENG DATA JI J. Chem. Eng. Data PD JUL-AUG PY 2001 VL 46 IS 4 BP 873 EP 874 DI 10.1021/je000373f PG 2 WC Thermodynamics; Chemistry, Multidisciplinary; Engineering, Chemical SC Thermodynamics; Chemistry; Engineering GA 455TL UT WOS:000170043800018 ER PT J AU Oakes, CS Rai, D AF Oakes, CS Rai, D TI Thermodynamic properties of aqueous HClO4 to 373 K and at low pressure: A comprehensive Pitzer ion-interaction model SO JOURNAL OF CHEMICAL AND ENGINEERING DATA LA English DT Article ID MOLAR HEAT-CAPACITIES; ACTIVITY-COEFFICIENTS; ELECTROLYTE-SOLUTIONS; OSMOTIC COEFFICIENTS; PERCHLORIC-ACID; VOLUMES; APPARENT; TEMPERATURE; 25-DEGREES-C; ENTHALPY AB We present a Pitzer ion-interaction model fit to most of the available isopiestic, dilution enthalpy, heat capacity, and volumetric data for HClO4(aq). Osmotic and activity coefficients are accurately reproduced for molalities between infinite dilution and 8 mol kg(-1) at 298 K. Isopiestic data at temperatures other than 298 K do not appear to be reliable. The dilution enthalpy data at 298 K are also reproducible to 8 mol kg(-1); consequently, HClO4(aq) activities may be calculated to 8 mol kg(-1) at 298 K and at somewhat higher or lower temperatures with only minor losses in confidence. Heat capacity data do not extend beyond 1.7 mol kg(-1) at 298 K and 1.0 mol kg(-1) at T > 328 K, and interlaboratory agreement is poor. Consequently, activity coefficients and thermal properties may only be calculated to about 1 mol kg(-1) at 373 K. There are numerous volumetric data for molalities between 0.02 and 18 mol kg(-1) and at 298 K; however, there are large variances between datasets at m > 5 mol kg(-1). Volumetric data at T > 348 K are limited to one study and m < 1 mol kg(-1). The volumetric form of the model is simple but due to disagreement between datasets is considered to have large uncertainties. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Oakes, CS (reprint author), Rutgers State Univ, Piscataway, NJ 08854 USA. NR 54 TC 3 Z9 3 U1 1 U2 6 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0021-9568 J9 J CHEM ENG DATA JI J. Chem. Eng. Data PD JUL-AUG PY 2001 VL 46 IS 4 BP 875 EP 884 DI 10.1021/je000051b PG 10 WC Thermodynamics; Chemistry, Multidisciplinary; Engineering, Chemical SC Thermodynamics; Chemistry; Engineering GA 455TL UT WOS:000170043800019 ER PT J AU Faulon, JL Sault, AG AF Faulon, JL Sault, AG TI Stochastic generator of chemical structure. 3. Reaction network generation SO JOURNAL OF CHEMICAL INFORMATION AND COMPUTER SCIENCES LA English DT Article ID PYROLYSIS; TIME AB A new method to generate chemical reaction network is proposed. The particularity of the method is that network generation and mechanism reduction are performed simultaneously using sampling techniques. Our method is tested for hydrocarbon thermal cracking. Results and theoretical arguments demonstrate that our method scales in polynomial time while other deterministic network generators scale in exponential time. This finding offers the possibility of investigating complex reacting systems such as those studied in petroleum refining and combustion. C1 Sandia Natl Labs, Computat Biol & Mat Technol Dept, Albuquerque, NM 87185 USA. Sandia Natl Labs, Catalyt & Porous Mat Dept, Albuquerque, NM 87185 USA. RP Faulon, JL (reprint author), Sandia Natl Labs, Computat Biol & Mat Technol Dept, POB 5800, Albuquerque, NM 87185 USA. NR 25 TC 22 Z9 22 U1 1 U2 4 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0095-2338 J9 J CHEM INF COMP SCI JI J. Chem. Inf. Comput. Sci. PD JUL-AUG PY 2001 VL 41 IS 4 BP 894 EP 908 DI 10.1021/ci000029m PG 15 WC Chemistry, Multidisciplinary; Computer Science, Information Systems; Computer Science, Interdisciplinary Applications SC Chemistry; Computer Science GA 456RC UT WOS:000170095200004 PM 11500106 ER PT J AU Habib, S Lindenberg, K Lythe, G Molina-Paris, C AF Habib, S Lindenberg, K Lythe, G Molina-Paris, C TI Diffusion-limited reaction in one dimension: Paired and unpaired nucleation SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID CLOSURE SCHEMES; ANNIHILATION; KINETICS; DYNAMICS; SYSTEMS; MODEL; COAGULATION; GROWTH; KINKS AB We study the dynamics of diffusing particles in one space dimension with annihilation on collision and nucleation (creation of particles) with constant probability per unit time and length. The cases of nucleation of single particles and nucleation in pairs are considered. A new method of analysis permits exact calculation of the steady-state density and its time evolution in terms of the three parameters describing the microscopic dynamics: the nucleation rate, the initial separation of nucleated pairs, and the diffusivity of a particle. For paired nucleation at sufficiently small initial separation the nucleation rate is proportional to the square of the steady-state density. For unpaired nucleation, and for paired nucleation at sufficiently large initial separation, the nucleation rate is proportional to the cube of the steady-state density. (C) 2001 American Institute of Physics. C1 Univ Calif Los Alamos Natl Lab, Theoret Div T8, Los Alamos, NM 87545 USA. Univ Calif San Diego, Dept Chem & Biochem 0340, La Jolla, CA 92093 USA. Univ Carlos III Madrid, GISC, Leganes 28911, Spain. CSIC, INTA, Ctr Astrobiol, Madrid 28850, Spain. RP Habib, S (reprint author), Univ Calif Los Alamos Natl Lab, Theoret Div T8, POB 1663, Los Alamos, NM 87545 USA. OI Lythe, Grant/0000-0001-7966-5571 NR 53 TC 18 Z9 18 U1 0 U2 5 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD JUL 1 PY 2001 VL 115 IS 1 BP 73 EP 89 DI 10.1063/1.1372763 PG 17 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 444ED UT WOS:000169385300010 ER PT J AU Rodriguez, JA Ricart, JM Clotet, A Illas, F AF Rodriguez, JA Ricart, JM Clotet, A Illas, F TI Density functional studies on the adsorption and decomposition of SO2 on Cu(100) SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID ABSORPTION FINE-STRUCTURE; TRANSITION-METAL SURFACES; ELECTRONIC-STRUCTURE CALCULATIONS; TOTAL-ENERGY CALCULATIONS; AB-INITIO CALCULATIONS; FIRST-PRINCIPLES; SULFUR-DIOXIDE; CLUSTER MODEL; PLANE-WAVE; DISSOCIATIVE CHEMISORPTION AB Density functional calculations in combination with cluster and slab models (periodic super-cell approach) were used to investigate the bonding and chemistry SO2 on Cu(100). For small coverages of SO2, the stability of the different bonding modes increases according to the eta (1)-S < eta (2)-S,O < eta (2)-O,O < eta (3)-S,O,O sequence. Large coverages make impossible eta (3)-S,O,O bonding, and under such conditions the most stable conformations involve eta (2)-O,O or eta (2)-S,O bonding. These adsorption geometries can be expected when SO2 is coadsorbed with substantial amounts of O. The bonding mechanism of SO2 on copper involves a Cu(3d,4s)--> SO2(LUMO) electron transfer that leads to a weakening and elongation of the S-O bonds. The eta (3)-S,O,O conformations exhibit the biggest adsorption energies, the largest charge transfers, and the weakest S-O bonds. These conformations are ideal precursors for the dissociation of the SO2 molecule. From a thermochemical viewpoint, it is much easier to generate SO3(3SO(2)--> 2SO(3)+S,DeltaE=similar to +1 kcal/mol) than to form SO(SO2--> SO+O,DeltaE=similar to +20 kcal/mol) as an intermediate during the decomposition of sulfur dioxide on Cu(100). SO and SO3 behave as net electron acceptors when bonded to copper, with the electron density on their S atoms increasing in the following order: SO3< SO2< SO adsorbate repulsions. The multidentate nature of SO2 and SO3 opens the possibility for a complex DeSO(x) chemistry on metal surfaces. (C) 2001 American Institute of Physics. C1 Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. Univ Rovira & Virgili, Dept Quim Fis & Inorgan, Tarragona 43005, Spain. Univ Rovira & Virgili, Inst Estudis Avancats, Tarragona 43005, Spain. Univ Barcelona, Dept Quim Fis, E-08028 Barcelona, Spain. Univ Barcelona, Ctr Recerca Quim Teor, E-08028 Barcelona, Spain. RP Rodriguez, JA (reprint author), Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. RI Illas, Francesc /C-8578-2011; Clotet, Anna/K-8200-2014; Ricart, Josep/K-9802-2014 OI Illas, Francesc /0000-0003-2104-6123; Clotet, Anna/0000-0003-0543-6607; Ricart, Josep/0000-0002-2610-5535 NR 88 TC 49 Z9 49 U1 2 U2 6 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD JUL 1 PY 2001 VL 115 IS 1 BP 454 EP 465 DI 10.1063/1.1377884 PG 12 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 444ED UT WOS:000169385300050 ER PT J AU Kalyuzhnyi, YV Cummings, PT AF Kalyuzhnyi, YV Cummings, PT TI Multicomponent mixture of charged hard-sphere chain molecules in the polymer mean-spherical approximation SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID INTEGRAL-EQUATION THEORY; DIRECTIONAL ATTRACTIVE FORCES; RESTRICTED PRIMITIVE MODEL; LIQUID-VAPOR COEXISTENCE; CHEMICAL ASSOCIATION; THERMODYNAMIC PROPERTIES; ELECTROLYTE-SOLUTIONS; IONIC FLUIDS; FLEXIBLE POLYELECTROLYTES; ASYMMETRIC ELECTROLYTES AB The analytical solution of the recently proposed ideal chain polymer mean-spherical approximation [Kalyuzhnyi, Mol. Phys. 94, 735 (1998)] is presented for the multicomponent mixture of charged hard-sphere linear chain flexible molecules. The solution applies to any mixture of chain molecules with arbitrary distribution of the charge and size of the beads along the molecular backbone. Closed form analytical expressions for the internal energy, Helmholtz free energy, chemical potentials, and pressure are derived. By way of illustration thermodynamical properties of several versions of the fluid of charged chain molecules of different length, including the molecules with uniform, diblock, and alternating distribution of the charge, are studied. Theoretical predictions are in reasonable agreement with available computer simulation predictions. We also present the liquid-gas phase diagrams for systems with diblock and alternating distribution of the charge. (C) 2001 American Institute of Physics. C1 Inst Condensed Matter Phys, UA-79011 Lviv, Ukraine. Univ Tennessee, Dept Chem Engn, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Chem Technol, Oak Ridge, TN 37831 USA. RP Kalyuzhnyi, YV (reprint author), Inst Condensed Matter Phys, Svientsitskoho 1, UA-79011 Lviv, Ukraine. RI Cummings, Peter/B-8762-2013 OI Cummings, Peter/0000-0002-9766-2216 NR 42 TC 20 Z9 20 U1 0 U2 6 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD JUL 1 PY 2001 VL 115 IS 1 BP 540 EP 551 DI 10.1063/1.1376426 PG 12 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 444ED UT WOS:000169385300060 ER PT J AU Mikhailovich, V Lapa, S Gryadunov, D Sobolev, A Strizhkov, B Chernyh, N Skotnikova, O Irtuganova, O Moroz, A Litvinov, V Vladimirskii, M Perelman, M Chernousova, L Erokhin, V Zasedatelev, A Mirzabekov, A AF Mikhailovich, V Lapa, S Gryadunov, D Sobolev, A Strizhkov, B Chernyh, N Skotnikova, O Irtuganova, O Moroz, A Litvinov, V Vladimirskii, M Perelman, M Chernousova, L Erokhin, V Zasedatelev, A Mirzabekov, A TI Identification of rifampin-resistant Mycobacterium tuberculosis strains by hybridization, PCR, and ligase detection reaction on oligonucleotide microchips SO JOURNAL OF CLINICAL MICROBIOLOGY LA English DT Article ID ANTIMICROBIAL AGENT RESISTANCE; GROWTH INDICATOR TUBE; LINE PROBE ASSAY; CLINICAL SPECIMENS; RAPID DETECTION; TESTING SUSCEPTIBILITY; SPECIES IDENTIFICATION; MB/BACT SYSTEM; MUTATIONS; POLYMORPHISM AB Three nerv molecular approaches were developed to identify drug-resistant strains of Mycobacterium tuberculosis using biochips with oligonucleotides immobilized in polyacrylamide gel pads. These approaches are significantly faster than traditional bacteriological methods. All three approaches-hybridization, PCR, and ligase detection reaction-were designed to analyze an 81-bp fragment of the gene rpoB encoding the beta -subunit of RNA polymerase, where most known mutations of rifampin resistance are located. The call set for hybridization analysis consisted of 42 immobilized oligonucleotides and enabled us to identify 30 mutant variants of the rpoB gene within 24 h. These variants are found in 95% of all mutants whose rifampin resistance is caused by mutations in the 81-bp fragment. Using the second approach, allele-specific on-chip PCR, it was possible to directly identify mutations in clinical samples within 1.5 h. The third approach, on-chip ligase detection reaction, was sensitive enough to reveal rifampin-resistant strains in a model mixture containing 1% of resistant and 99% of susceptible bacteria. This level of sensitivity is comparable to that from the determination of M. tuberculosis drug resistance by using standard bacteriological tests. C1 VA Engelhardt Mol Biol Inst, Biochip Technol Ctr, Moscow 119991, Russia. Russian Acad Med Sci, Cent TB Res Inst, Moscow, Russia. IM Sechenov Med Acad, Res Inst Phthisiopulmonol, Moscow, Russia. Moscow Govt, Moscow Antitb Ctr, Moscow, Russia. Argonne Natl Lab, Biochip Technol Ctr, Argonne, IL 60439 USA. RP Mirzabekov, A (reprint author), VA Engelhardt Mol Biol Inst, Biochip Technol Ctr, 32 Vavilova St,GSP-1, Moscow 119991, Russia. RI Gryadunov, Dmitry/F-5251-2014 OI Gryadunov, Dmitry/0000-0003-3183-318X NR 38 TC 89 Z9 117 U1 0 U2 7 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1752 N ST NW, WASHINGTON, DC 20036-2904 USA SN 0095-1137 J9 J CLIN MICROBIOL JI J. Clin. Microbiol. PD JUL PY 2001 VL 39 IS 7 BP 2531 EP 2540 DI 10.1128/JCM.39.7.2531-2540.2001 PG 10 WC Microbiology SC Microbiology GA 447RN UT WOS:000169586400024 PM 11427565 ER PT J AU Fowler, JS Volkow, ND AF Fowler, JS Volkow, ND TI (18)FDG for the study of central nervous system drugs SO JOURNAL OF CLINICAL PHARMACOLOGY LA English DT Article ID CEREBRAL GLUCOSE-UTILIZATION; F-18-LABELED 2-DEOXY-2-FLUORO-D-GLUCOSE; F-18 C1 Brookhaven Natl Lab, Upton, NY 11973 USA. RP Fowler, JS (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. NR 8 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 0091-2700 J9 J CLIN PHARMACOL JI J. Clin. Pharmacol. PD JUL PY 2001 SU S BP 9S EP 10S PG 2 WC Pharmacology & Pharmacy SC Pharmacology & Pharmacy GA 450FC UT WOS:000169730000003 ER PT J AU Champagne, NJ Berryman, JG Buettner, HM AF Champagne, NJ Berryman, JG Buettner, HM TI FDFD: A 3D finite-difference frequency-domain code for electromagnetic induction tomography SO JOURNAL OF COMPUTATIONAL PHYSICS LA English DT Article ID GROUND-PENETRATING RADAR; INVERSION; FIELDS; SCATTERING; APPROXIMATION AB A new 3D code for electromagnetic induction tomography with intended applications to environmental imaging problems has been developed. The approach consists of calculating the fields within a volume using an implicit finite-difference frequency-domain formulation. The volume is terminated by an anisotropic perfectly matched layer region that simulates an infinite domain by absorbing outgoing waves. Extensive validation of this code has been done using analytical and semianalytical results from other codes. and some of those results are presented in this paper. The new code is written in Fortran 90 and is designed to be easily parallelized. Finally. an adjoint held method of data inversion. developed in parallel for solving the fully nonlinear inverse problem for electrical conductivity imaging (e.g.. for mapping underground conducting plumes). uses this code to provide solvers for both forward and adjoint fields. Results obtained from this inversion method for high-contrast media are encouraging and provide a significant improvement over those obtained from linearized inversion methods. (C) 2001 Academic Press. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Champagne, NJ (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RI Berryman, James/A-9712-2008 NR 33 TC 25 Z9 25 U1 0 U2 4 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0021-9991 J9 J COMPUT PHYS JI J. Comput. Phys. PD JUL 1 PY 2001 VL 170 IS 2 BP 830 EP 848 DI 10.1006/jcph.2001.6765 PG 19 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA 454HP UT WOS:000169967400017 ER PT J AU Schroth, MH Oostrom, M Wietsma, TW Istok, JD AF Schroth, MH Oostrom, M Wietsma, TW Istok, JD TI In-situ oxidation of trichloroethene by permanganate: effects on porous medium hydraulic properties SO JOURNAL OF CONTAMINANT HYDROLOGY LA English DT Article DE DNAPL; permanganate; in-situ oxidation; relative permeability ID POTASSIUM-PERMANGANATE; DISSOLUTION; REDUCTION; SOLIDS; MODEL; FLOW; TCE; PCE AB In-situ oxidation of dense nonaqueous-phase Liquids (DNAPLs) by strong oxidants such as potassium permanganate (KMnO4) has been proposed as a possible DNAPL remediation strategy. In this study, we investigated the effects of in-situ trichloroethene (TCE) oxidation by KMnO4 on porous medium hydraulic properties. In particular, we wanted to determine the overall effects of concurrent solid phase (MnO2) precipitation, gas (CO2) evolution and TCE dissolution resulting from the oxidation reaction on the porous medium's aqueous-phase relative permeability, k(rw). Three TCE removal experiments were conducted in a 95-cm long, 5.1-cm i.d. glass column, which was homogeneously packed with well-characterized 30/40-mesh silica sand. TCE was emplaced in the sand-pack in residual, entrapped form through a sequence of water/TCE imbibition and drainage steps. The column was then flushed under constant aqueous flux conditions for up to 104 h with either deionized water (reference experiment), deionized water containing 5 mM KMnO4 or deionized water containing 5 mM KMnO4 and 300 mM Na2HPO4. Aqueous-phase relative permeabilities were computed from measured flow rates and measurements of aqueous-phase pressure head, h obtained using pressure transducers connected to tensiometers distributed along the column length. A dual-energy gamma radiation system was used to monitor changes in fluid saturation that occurred during each experiment. In addition, column effluent samples were collected for chemical analyses. Dissolution of TCE during deionized water flushing led to an increase in k(rw) by similar to 22% and a local reduction in h. On the other hand, Vigorous CO2 gas production and precipitation of MnO2 was visually observed during flushing with deionized water that contained 5 mM KMnO4. As a consequence, k(rw) declined by similar to 96% and h increased locally by more than 1000 cm H2O during the first 24 h of the experiment, causing sand-pack ruptures and pump failure. Conversely, less CO2 gas production and MnO2 precipitation was visually observed during flushing with deionized water that contained 5 mM KMnO4 and 300 mM Na2HPO4. Consequently, only small increases in h (< 15 cm H2O) were observed in this experiment due to a reduction in k(rw) of similar to 53%. While we must attribute changes in h due to variations in k(rw) to our specific experimental design (constant aqueous flux, one-dimensional flow experiments), these experiments nevertheless confirm that successful application of in situ chemical oxidation of TCE requires consideration of detrimental processes such as MnO2 precipitation and CO2 gas formation. In addition, our results indicate that utilization of a buffered oxidant solution may improve the effectiveness of in-situ oxidation of TCE by KMnO4 in otherwise weakly buffered porous media. (C) 2001 Elsevier Science B.V. All rights reserved. C1 ETH Zurich, Swiss Fed Inst Technol, Inst Terr Ecol, CH-8952 Schlieren, Switzerland. Pacific NW Natl Lab, Multifluid Flow Res Lab, Richland, WA 99352 USA. Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. Oregon State Univ, Dept Civil Construct & Environm Engn, Corvallis, OR 97331 USA. RP Schroth, MH (reprint author), ETH Zurich, Swiss Fed Inst Technol, Inst Terr Ecol, Grabenstr 3, CH-8952 Schlieren, Switzerland. NR 29 TC 66 Z9 67 U1 5 U2 21 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0169-7722 J9 J CONTAM HYDROL JI J. Contam. Hydrol. PD JUL PY 2001 VL 50 IS 1-2 BP 79 EP 98 DI 10.1016/S0169-7722(01)00098-5 PG 20 WC Environmental Sciences; Geosciences, Multidisciplinary; Water Resources SC Environmental Sciences & Ecology; Geology; Water Resources GA 449WA UT WOS:000169709100005 PM 11475162 ER PT J AU Spruytte, SG Larson, MC Wampler, W Coldren, CW Petersen, HE Harris, JS AF Spruytte, SG Larson, MC Wampler, W Coldren, CW Petersen, HE Harris, JS TI Nitrogen incorporation in group III-nitride-arsenide materials grown by elemental source molecular beam epitaxy SO JOURNAL OF CRYSTAL GROWTH LA English DT Article; Proceedings Paper CT 11th International Conference on Molecular Beam Epitaxy (MBE-XI) CY SEP 11-15, 2000 CL BEIJING, PEOPLES R CHINA SP China Natl Nat Sci Fdn, Inst Semiconductor, CAS, Inst Phys, CAS, State Key Lab Funct Mat Informat, Inst Met, CAS, Hong Kong Univ Sci & Technol, Univ Hong Kong, Lab New Mat, Chinese Acad Sci, Lab New Mat, VG Semicon, Riber DE characterization; defects; diffusion; molecular beam epitaxy; semiconducting IIIV materials; laser diodes ID VERTICAL-CAVITY LASERS; QUANTUM-WELL LASERS; GAINNAS; GAAS; LAYERS AB Group III-nitride-arsenides are promising materials for long wavelength opto-electronic: devices grown on GaAs substrates. The growth of nitride-arsenides was performed in an elemental solid source molecular beam epitaxy system with a plasma cell to supply reactive nitrogen. Growth is carried out with plasma conditions that maximize the amount of atomic nitrogen versus molecular nitrogen, as determined from the emission spectrum of the plasma. The group III growth rate controls the nitrogen concentration in the film. The photoluminescence intensity of GaNAs and GaInNAs quantum wells (QWs) increases drastically and shifts to shorter wavelengths following high temperature anneal. Nitrogen diffusion out of the QWs is responsible for the wavelength shift, We observe a decrease of interstitial nitrogen after anneal. Vertical-cavity surface-emitting lasers with GaInNAs QWs demonstrated a continous-wave operation, To limit nitrogen diffusion, the GaAs barriers surrounding the GaInNAs: QWs were replaced by GaNAs barriers, This new active region resulted in devices emitting at 1.3 mum, (C) 2001 Elsevier Science B,V, All rights reserved. C1 Stanford Univ, Solid State & Photon Lab, Dept Elect Engn, CISX, Stanford, CA 94305 USA. Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Agil Commun, Santa Barbara, CA USA. Sandia Natl Labs, Radiat Solid Interact & Proc Dept 1111, Albuquerque, NM 87185 USA. RP Harris, JS (reprint author), Stanford Univ, Solid State & Photon Lab, Dept Elect Engn, CISX, Room 328,Via Ortega, Stanford, CA 94305 USA. EM harris@snow.stanford.edu NR 23 TC 105 Z9 105 U1 1 U2 9 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-0248 EI 1873-5002 J9 J CRYST GROWTH JI J. Cryst. Growth PD JUL PY 2001 VL 227 BP 506 EP 515 DI 10.1016/S0022-0248(01)00757-6 PG 10 WC Crystallography; Materials Science, Multidisciplinary; Physics, Applied SC Crystallography; Materials Science; Physics GA 447EE UT WOS:000169557600099 ER PT J AU Hong, YG Tu, CW Ahrenkiel, RK AF Hong, YG Tu, CW Ahrenkiel, RK TI Improving properties of GaInNAs with a short-period GaInAs/GaNAs superlattice SO JOURNAL OF CRYSTAL GROWTH LA English DT Article; Proceedings Paper CT 11th International Conference on Molecular Beam Epitaxy (MBE-XI) CY SEP 11-15, 2000 CL BEIJING, PEOPLES R CHINA SP China Natl Nat Sci Fdn, Inst Semiconductor, CAS, Inst Phys, CAS, State Key Lab Funct Mat Informat, Inst Met, CAS, Hong Kong Univ Sci & Technol, Univ Hong Kong, Lab New Mat, Chinese Acad Sci, Lab New Mat, VG Semicon, Riber DE molecular beam epitaxy; superlattices; nitrides ID ELECTRON EFFECTIVE-MASS; GANAS/GAAS; NITROGEN; INGAASN AB Short-period superlattices (SLs) of GaInAs/GaNAs were grown by gas-source molecular beam epitaxy. Hall measurement shows electron mobility is improved by a factor of almost two. Improvement of electron mobility can be attributed to the smaller effective mass of the SL structure. The photoluminescence (PL) intensity is improved by rapid thermal annealing (RTA). The PL intensity of digital alloys is 2.5-3 times higher than that of the random alloy at room temperature, and the improvement is even greater at low temperature (10 K) by a factor of about 12, The optimized RTA condition for short-period SLs is 700<^>C and 10s in Nz ambient. Photoconductive decay measurements show longer carrier lift time for the: SL samples, 0.2 mus vs. 0.1 mus for the random alloy, which could be caused by charge separation due to the type-II band lineup of the GaIn0.08As/GaN0.03As SLs. (C) 2001 Elsevier Science B,V. All rights reserved. C1 Univ Calif San Diego, Dept Elect & Comp Engn, La Jolla, CA 92093 USA. Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Hong, YG (reprint author), Univ Calif San Diego, Dept Elect & Comp Engn, La Jolla, CA 92093 USA. NR 14 TC 15 Z9 17 U1 1 U2 7 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-0248 J9 J CRYST GROWTH JI J. Cryst. Growth PD JUL PY 2001 VL 227 BP 536 EP 540 DI 10.1016/S0022-0248(01)00762-X PG 5 WC Crystallography; Materials Science, Multidisciplinary; Physics, Applied SC Crystallography; Materials Science; Physics GA 447EE UT WOS:000169557600104 ER PT J AU Sarma, GB Keiser, JR Wang, XL Swindeman, RW AF Sarma, GB Keiser, JR Wang, XL Swindeman, RW TI Modeling studies to predict stresses in composite floor tubes of black liquor recovery boilers SO JOURNAL OF ENGINEERING MATERIALS AND TECHNOLOGY-TRANSACTIONS OF THE ASME LA English DT Article ID NEUTRON-DIFFRACTION; RESIDUAL-STRESSES AB The results of finite element modeling studies to analyze the composite floor tubes of recovery boilers used by the pulp and paper industry: are presented. Thermal and mechanical analyses have been carried out to examine the changes in the stresses during a normal operating cycle. Three different materials for the clad layer have been studied-304L stainless steel and alloys 625 and 825. The results show that the coefficient of thermal expansion and the strength of the clad layer play a significant role in the stress variation due to the hearing and cooling associated with an operating cycle, with implications for the development of cracks in the tubes due to stress corrosion cracking. The analyses also show that axial stress in the carbon steel layer is compressive at the fireside tube crown and tensile in the membrane. which provides a possible explanation for the commonly observed differences in crack propagation in tubes and membranes. C1 Oak Ridge Natl Lab, Div Math & Comp Sci, Oak Ridge, TN 37831 USA. Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. Oak Ridge Natl Lab, Spallat Neutron Source Project, Oak Ridge, TN 37831 USA. RP Sarma, GB (reprint author), Oak Ridge Natl Lab, Div Math & Comp Sci, Oak Ridge, TN 37831 USA. RI Wang, Xun-Li/C-9636-2010 OI Wang, Xun-Li/0000-0003-4060-8777 NR 12 TC 1 Z9 2 U1 0 U2 1 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA THREE PARK AVE, NEW YORK, NY 10016-5990 USA SN 0094-4289 J9 J ENG MATER-T ASME JI J. Eng. Mater. Technol.-Trans. ASME PD JUL PY 2001 VL 123 IS 3 BP 349 EP 354 DI 10.1115/1.1372709 PG 6 WC Engineering, Mechanical; Materials Science, Multidisciplinary SC Engineering; Materials Science GA 452HD UT WOS:000169851400016 ER PT J AU Kim, J Walters, RW AF Kim, J Walters, RW TI Oxygen transfer at low drop weirs SO JOURNAL OF ENVIRONMENTAL ENGINEERING-ASCE LA English DT Article ID AERATION AB Oxygen transfer into water at low-drop weirs was studied by using a prototype-scale, recirculating hydraulic flume with a weir width of 0.61 m, and a downstream channel width of 1.22 m. An enhanced-oxygen environment was used to maintain sufficient difference between saturation and upstream dissolved oxygen concentrations to reduce the experimental uncertainty. The variation in the deficit ratio was a function of tailwater depth H was evaluated by using unit discharges q of 167, 334, and 502 m(3)/hr m and weir heights W of 0.54, 1.04, and 1.36 m. A semitheoretical equation for predicting r as a function of jet Froude number F-J, drop height h, and H was fitted to observed values by nonlinear regression analysis. An assumed value of 0.667 for maximum H/h (found in the literature) proved acceptable. We concluded that tailwater depths are important to predict oxygen transfer at low-drop weirs, but that designing for optimum tailwater depth to maximize oxygen transfer may not be as important as was previously thought, because large optimum ranges for H/h were observed in this study. C1 Argonne Natl Lab, Div Environm Res, Argonne, IL 60439 USA. Gonzaga Univ, Dept Civil Engn, Spokane, WA 99258 USA. RP Kim, J (reprint author), Lawrence Berkeley Lab, Div Earth Sci, 1 Cyclotron Rd, Berkeley, CA 94720 USA. NR 11 TC 9 Z9 9 U1 0 U2 1 PU ASCE-AMER SOC CIVIL ENGINEERS PI RESTON PA 1801 ALEXANDER BELL DR, RESTON, VA 20191-4400 USA SN 0733-9372 J9 J ENVIRON ENG-ASCE JI J. Environ. Eng.-ASCE PD JUL PY 2001 VL 127 IS 7 BP 604 EP 610 DI 10.1061/(ASCE)0733-9372(2001)127:7(604) PG 7 WC Engineering, Environmental; Engineering, Civil; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 443MR UT WOS:000169345400007 ER PT J AU Sato, CK Hartenstein, SD Motes, W AF Sato, CK Hartenstein, SD Motes, W TI Photosonolysis of TCA, TCE, and PCE in flow-through reactor system SO JOURNAL OF ENVIRONMENTAL ENGINEERING-ASCE LA English DT Article ID AQUEOUS-SOLUTION; CHLORINATED HYDROCARBONS; ULTRASONIC IRRADIATION; ULTRAVIOLET-LIGHT; HYDROGEN-PEROXIDE; TITANIUM-DIOXIDE; BY-PRODUCTS; WATER; DECOMPOSITION; DEGRADATION AB Photosonolysis of 1,1,1-trichloroethane (TCA), trichloroethylene (TCE), and tetrachloroethylene (PCE) in water was investigated using a cup-horn, flow-through reactor system. Water containing titanium dioxide was deliberately contaminated with a mixture of volatile organic compound (VOC)-TCA, TCE, and PCE-and individual VOC. These solutions were irradiated with ultraviolet light (UV) and ultrasonic waves (US), independently and concurrently (UVUS). The values of the first-order degradation rate constant and the removal efficiency for the VOC were evaluated for the W, US, and UVUS treatments. The results showed that the concurrent use of UV and US increased the VOC degradation rate and removal efficiency beyond the additive effect of UV and US, suggesting that the UVUS effect on the decomposition of the VOC is synergistic under certain conditions. TCE and PCE were more readily degraded than TCA, suggesting that double-bond cleavage is one of the initial degradation pathways. With the reactor specifications used, the photosonolysis process can produce water meeting the drinking water standard (MCLs of 5 mug/L) for TCE and PCE with a removal efficiency of approximately 90%. C1 Idaho State Univ, Coll Engn, Pocatello, ID 83209 USA. Lockheed Martin Idaho Technol Co, Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. RP Sato, CK (reprint author), Idaho State Univ, Coll Engn, Pocatello, ID 83209 USA. NR 32 TC 11 Z9 11 U1 0 U2 0 PU ASCE-AMER SOC CIVIL ENGINEERS PI RESTON PA 1801 ALEXANDER BELL DR, RESTON, VA 20191-4400 USA SN 0733-9372 J9 J ENVIRON ENG-ASCE JI J. Environ. Eng.-ASCE PD JUL PY 2001 VL 127 IS 7 BP 620 EP 629 DI 10.1061/(ASCE)0733-9372(2001)127:7(620) PG 10 WC Engineering, Environmental; Engineering, Civil; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 443MR UT WOS:000169345400009 ER PT J AU Glenn, EP Waugh, WJ Moore, D McKeon, C Nelson, SG AF Glenn, EP Waugh, WJ Moore, D McKeon, C Nelson, SG TI Revegetation of an abandoned uranium millsite on the Colorado Plateau, Arizona SO JOURNAL OF ENVIRONMENTAL QUALITY LA English DT Article ID DESERT AB We attempted to restore native plants on disturbed sites at a former uranium mill on the Colorado Plateau near Tuba City, AZ. Four-wing saltbush [Atriplex canescens (Pursh) Nutt.] was successfully established in compacted caliche soil and in unconsolidated dune soil when transplants were irrigated through the first summer with 20 U plant/wk. The caliche soil was ripped before planting to improve water-holding capacity. The diploid saltbush variety, angustifolia, had higher survival and growth than the common tetraploid variety, occidentalis, especially on dune soil. The angustifolia variety grew to 0.3 to 0.4 m(3) per plant over 3 yr even though irrigation was provided only during the establishment year. By contrast, direct seeding of a variety of native forbs, grasses, and shrubs yielded poor results, despite supplemental irrigation throughout the first summer. In this and environment (precipitation = 100 to 200 mm/yr), the most effective revegetation strategy is to establish keystone native shrubs, such as four-wing saltbush, using transplants and irrigation during the establishment year, rather than attempting to establish a diverse plant community all at once. C1 US DOE, Environm Sci Lab, Grand Junction, CO 81503 USA. Univ Arizona, Environm Res Lab, Tucson, AZ 85721 USA. RP Waugh, WJ (reprint author), US DOE, Environm Sci Lab, 2597 B 3-4 Rd, Grand Junction, CO 81503 USA. NR 33 TC 19 Z9 20 U1 4 U2 17 PU AMER SOC AGRONOMY PI MADISON PA 677 S SEGOE RD, MADISON, WI 53711 USA SN 0047-2425 J9 J ENVIRON QUAL JI J. Environ. Qual. PD JUL-AUG PY 2001 VL 30 IS 4 BP 1154 EP 1162 PG 9 WC Environmental Sciences SC Environmental Sciences & Ecology GA 539GW UT WOS:000174863000006 PM 11476492 ER PT J AU Seaman, JC Meehan, T Bertsch, PM AF Seaman, JC Meehan, T Bertsch, PM TI Immobilization of cesium-137 and uranium in contaminated sediments using soil amendments SO JOURNAL OF ENVIRONMENTAL QUALITY LA English DT Article ID DESORPTION BEHAVIOR; SORPTION; LEAD; ILLITE; HYDROXYAPATITE; APATITE; MIGRATION; CS-137; PB AB Batch and dynamic leaching methods were used to evaluate the effectiveness of hydroxyapatite (HA), illite, and zeolite, alone and in combination, as soil additives for reducing the migration of cesium-137 (Cs-137(+)) and uranium (U) from contaminated sediments. Amendment treatments ranging from 0 to 50 g kg(-1) were added to the sediment and equilibrated in 0.001 M CaCl2. After equilibration, the treatment supernatants were analyzed for Cs-137(+), U, PO4, and other metals. The residual sediments were then extracted overnight using one of the following: 1.0 M NH4Cl, 0.5 M CaCl2, or the Toxicity Characteristic Leaching Procedure (TCLP) extractant. Cesium was strongly sorbed to the contaminated sediments, presumably due to interlayer fixation within native illitic clays. In fact, Cs-137(+) was below detection limits in the initial equilibration solutions, the CaCl2 extract, and the TCLP solution, regardless of amendment. Extractants selective for interlayer cations (1.0 M NH4Cl) were necessary to extract measurable levels of Cs-137(+). Addition of illitic clays further reduced Cs+ extractability, even when subjected to the aggressive extractants. Zeolite, however, was ineffective in reducing Cs+ mobility when subjected to the aggressive extractants. Hydroxyapatite was less effective than illite at reducing NW-extractable Cs+. Hydroxyapatite, and mixtures of HA with illite or zeolite, were highly effective in reducing U extractability in both batch and leaching tests. Uranium immobilization by HA was rapid with similar final U concentrations observed for equilibration times ranging from 1 h to 30 d. The current results demonstrate the effectiveness of soil amendments in reducing the mobility of U and Cs+, which makes in-place immobilization an effective remediation alternative. C1 Univ Georgia, Savannah River Ecol Lab, Adv Analyt Ctr Environm Sci, Aiken, SC 29802 USA. RP Seaman, JC (reprint author), Univ Georgia, Savannah River Ecol Lab, Adv Analyt Ctr Environm Sci, Aiken, SC 29802 USA. NR 40 TC 40 Z9 43 U1 3 U2 22 PU AMER SOC AGRONOMY PI MADISON PA 677 S SEGOE RD, MADISON, WI 53711 USA SN 0047-2425 J9 J ENVIRON QUAL JI J. Environ. Qual. PD JUL-AUG PY 2001 VL 30 IS 4 BP 1206 EP 1213 PG 8 WC Environmental Sciences SC Environmental Sciences & Ecology GA 539GW UT WOS:000174863000011 PM 11476497 ER PT J AU Rogers, A Ellsworth, DS Humphries, SW AF Rogers, A Ellsworth, DS Humphries, SW TI Possible explanation of the disparity between the in vitro and in vivo measurements of Rubisco activity: a study in loblolly pine grown in elevated pCO(2) SO JOURNAL OF EXPERIMENTAL BOTANY LA English DT Article DE Rubisco activity; elevated CO2 ID RIBULOSE-1,5-BISPHOSPHATE CARBOXYLASE OXYGENASE; RISING ATMOSPHERIC CO2; PHASEOLUS-VULGARIS L; RADIATA D. DON.; PHOTOSYNTHETIC ACCLIMATION; CARBON-DIOXIDE; GAS-EXCHANGE; FRUIT REMOVAL; SPRING WHEAT; LEAF AB Rubisco activity can be measured using gas exchange (in vivo) or using in vitro methods. Commonly in vitro methods yield activities that are less than those obtained in vivo. Rubisco activity was measured both in vivo and in vitro using a spectrophotometric technique in mature Pinus taeda L. (loblolly pine) trees grown using free-air CO2 enrichment in elevated (56 Pa) and current (36 Pa) pCO(2). In addition, for studies where both in vivo and in vitro values of Rubisco activity were reported net CO2 uptake rate (A) was modelled based on the in vivo and in vitro values of Rubisco activity reported in the literature. Both the modelling exercise and the experimental data showed that the in vitro values of Rubisco activity were insufficient to account for the observed values of A. A trichloroacetic acid (TCA) precipitation of the protein from samples taken in parallel with those used for activity analysis was co-electrophoresed with the extract used for determining in vitro Rubisco activity. There was significantly more Rubisco present in the TCA precipitated samples, suggesting that the underestimation of Rubisco activity in vitro was attributable to an insufficient extraction of Rubisco protein prior to activity analysis. Correction of in vitro values to account for the under-represented Rubisco yielded mechanistically valid values for Rubisco activity. However, despite the low absolute values for Rubisco activity determined in vitro, the trends reported with CO2 treatment concurred with, and were of equal magnitude to, those observed in Rubisco activity measured in vivo. C1 Brookhaven Natl Lab, Dept Environm Sci, Upton, NY 11973 USA. RP Rogers, A (reprint author), Brookhaven Natl Lab, Dept Environm Sci, Bldg 490D, Upton, NY 11973 USA. RI Rogers, Alistair/E-1177-2011; OI Rogers, Alistair/0000-0001-9262-7430; Ellsworth, David/0000-0002-9699-2272 NR 38 TC 29 Z9 31 U1 1 U2 11 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0022-0957 J9 J EXP BOT JI J. Exp. Bot. PD JUL PY 2001 VL 52 IS 360 BP 1555 EP 1561 DI 10.1093/jexbot/52.360.1555 PG 7 WC Plant Sciences SC Plant Sciences GA 457PR UT WOS:000170146400019 PM 11457916 ER PT J AU Hidalgo, C Padron, R Medina, R Tonino, P Alamo, L Simon, M Craig, R AF Hidalgo, C Padron, R Medina, R Tonino, P Alamo, L Simon, M Craig, R TI Mass/length measurement and composition of native purified myosin filaments from muscle SO JOURNAL OF GENERAL PHYSIOLOGY LA English DT Meeting Abstract C1 Univ Massachusetts, Sch Med, Dept Cell Biol, Worcester, MA 01655 USA. Inst Venezolano Invest Cient, Dept Biol Estructural, Caracas 1020A, Venezuela. Inst Venezolano Invest Cient, Ctr Fis, Caracas 1020A, Venezuela. Cent Univ Venezuela, Fac Ciencias, Ctr Microscopia Electron, Caracas, Venezuela. Brookhaven Natl Lab, Dept Biol, Upton, NY 11973 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU ROCKEFELLER UNIV PRESS PI NEW YORK PA 1114 FIRST AVE, 4TH FL, NEW YORK, NY 10021 USA SN 0022-1295 J9 J GEN PHYSIOL JI J. Gen. Physiol. PD JUL PY 2001 VL 118 IS 1 MA 18 BP 10A EP 10A PG 1 WC Physiology SC Physiology GA 451CD UT WOS:000169782800029 ER PT J AU Boonsiriseth, A Thorne, RM Lu, G Jordanova, VK Thomsen, MF Ober, DM Ridley, AJ AF Boonsiriseth, A Thorne, RM Lu, G Jordanova, VK Thomsen, MF Ober, DM Ridley, AJ TI A semiempirical equatorial mapping of AMIE convection electric potentials (MACEP) for the January 10, 1997, magnetic storm SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID RING CURRENT; LARGE-SCALE; FIELD; MODEL; WIND; PRECIPITATION; MAGNETOSPHERE; PHASE; DEPENDENCE; INSTRUMENT AB Owing to satellite and instrumental limitations, in situ magnetospheric electric field measurements are only available at isolated locations during storm time conditions, A global view of the inner magnetospheric convection electric field can be obtained by mapping ionospheric potentials into the equatorial plane. A mapping procedure for assimilative mapping of ionospheric electrodynamics (AMIE) ionospheric potentials (MACEP) is used to obtain convection patterns for the January 10, 1997, magnetic storm. The results are compared with the widely used empirical Volland-Stern model and the mapping of Weimer ionospheric potentials. While the gross temporal evolution of the large-scale potential drop across the magnetosphere is similar in all three models, detailed intercomparison shows that the MACEP procedure is capable of resolving highly variable and relatively small scale features of the electric field that are not treated by the Volland-Stern model nor seen from the Weimer mapping. The MACEP results are in reasonable agreement with limited electric field measurements from the electric field instrument on the Polar spacecraft and LANL measurements of thermal ion velocities at geosynchronous orbit during prestorm and recovery phase conditions. However, the inner boundary condition employed in the current version of AMIE is unable to reproduce the magnitude of the penetrating electric fields observed in the inner magnetosphere during the main phase of a storm. The addition of a penetration electric field associated with an asymmetric ring current in the dusk sector improved MACEP results at the duskside low-L region. C1 Univ Calif Los Angeles, Dept Atmospher Sci, Los Angeles, CA 90095 USA. High Altitude Observ, Boulder, CO 80307 USA. Univ New Hampshire, Ctr Space Sci, Durham, NH 03824 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Mission Res Corp, Nashua, NH 03062 USA. Univ Michigan, Ann Arbor, MI 48109 USA. RP Boonsiriseth, A (reprint author), Univ Calif Los Angeles, Dept Atmospher Sci, MS 7984,405 Hilgard Ave, Los Angeles, CA 90095 USA. RI Lu, Gang/A-6669-2011; Ridley, Aaron/F-3943-2011; OI Ridley, Aaron/0000-0001-6933-8534; Jordanova, Vania/0000-0003-0475-8743 NR 35 TC 24 Z9 24 U1 0 U2 1 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 JUL 1 PY 2001 VL 106 IS A7 BP 12903 EP 12917 DI 10.1029/1999JA000332 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 446VT UT WOS:000169535400013 ER PT J AU Schaub, H Alfriend, KT AF Schaub, H Alfriend, KT TI Impulsive feedback control to establish specific mean orbit elements of spacecraft formations SO JOURNAL OF GUIDANCE CONTROL AND DYNAMICS LA English DT Article AB An impulsive feedback control is developed to establish specific relative orbits for spacecraft formation flying, The relative orbit tracking errors are expressed in terms of mean orbit elements. The feedback control. based on Gauss's variational equations of motion, allows specific orbit elements or orbit element sets to be controlled with minimal impact on the remaining osculating orbit elements. This is advantageous when J(2)-invariant orbits are to be controlled, where only the argument of perigee and mean anomaly will drift apart at equal and opposite rates. The advantage of this impulsive feedback control, compared to optimal control solutions, is that it can operate with little computational effort and in a near-optimal manner, while requiring only a marginal penalty in fuel cost. When applied to the spacecraft formation flying problem, this control could also be used to perform general orbit corrections. Formulas are developed providing accurate estimates of the sensitivities of the mean semimajor axis and mean eccentricity with respect to the osculating inclination angle, with these sensitivities, the tracking error in semimajor axis, eccentricity, and inclination angle can be canceled within one orbit. C1 Sandia Natl Labs, Ctr 15211, Albuquerque, NM 87185 USA. Texas A&M Univ, Dept Aerosp Engn, College Stn, TX 77843 USA. RP Schaub, H (reprint author), Sandia Natl Labs, Ctr 15211, POB 5800,MS-1003, Albuquerque, NM 87185 USA. NR 12 TC 98 Z9 107 U1 0 U2 7 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 USA SN 0731-5090 J9 J GUID CONTROL DYNAM JI J. Guid. Control Dyn. PD JUL-AUG PY 2001 VL 24 IS 4 BP 739 EP 745 DI 10.2514/2.4774 PG 7 WC Engineering, Aerospace; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA 451KB UT WOS:000169800300013 ER PT J AU Kallosh, R Prokushkin, S Shmakova, M AF Kallosh, R Prokushkin, S Shmakova, M TI Domain walls with strings attached SO JOURNAL OF HIGH ENERGY PHYSICS LA English DT Article DE extra large dimensions; p-branes; classical theories of gravity; supergravity models ID SUPERGRAVITY; CREATION; BRANES AB We have constructed a bulk & brane action of IIA theory which describes a pair of BPS domain walls on S-1/Z(2), with strings attached. The walls are given by two orientifold O8-planes with coincident D8-branes and 'F1-D0'-strings are stretched between the walls. This static configuration satisfies all matching conditions for the string and domain wall sources and has 1/4 of unbroken supersymmetry. C1 Stanford Univ, Dept Phys, Stanford, CA 94305 USA. CIPA, Palo Alto, CA 94306 USA. Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Kallosh, R (reprint author), Stanford Univ, Dept Phys, Stanford, CA 94305 USA. EM kallosh@stanford.edu; prok@stanford.edu; shmakova@slac.stanford.edu NR 12 TC 6 Z9 6 U1 0 U2 0 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1029-8479 J9 J HIGH ENERGY PHYS JI J. High Energy Phys. PD JUL PY 2001 IS 7 AR 023 PG 13 WC Physics, Particles & Fields SC Physics GA 484ZU UT WOS:000171727700023 ER PT J AU Lersch, RA Fung, JL Hsieh, HB Smida, J Weier, HUG AF Lersch, RA Fung, JL Hsieh, HB Smida, J Weier, HUG TI Monitoring signal transduction in cancer: From chips to FISH SO JOURNAL OF HISTOCHEMISTRY & CYTOCHEMISTRY LA English DT Article; Proceedings Paper CT Joint Meeting of the Histochemical-Society/International-Society-for-Analytical-and-Molecular -Morphology CY FEB 02-07, 2001 CL SANTA FE, NEW MEXICO SP Histochem Soc, Int Soc Analyt & Molec Morphol DE spectral imaging; FISH; microarray; RNA; cancer AB The microarray format of RNA transcript analysis should provide new clues to carcinogenic processes. Because of the complex and heterogeneous nature of most tumor samples, histochemical techniques, particularly RNA fluorescent in situ hybridization (FISH), are required to test the predictions from microarray expression experiments. Here we describe our approach to verify new microarray data by examining RNA expression levels of five to seven different transcripts in a very few cells via FISH. C1 Lawrence Berkeley Lab, Div Life Sci, Berkeley, CA 94720 USA. GSF Forschungszentrum Umwelt & Gesundheit, Arbeitsgrp Zytogenet, Neuherberg, Germany. Univ Calif San Francisco, Sch Med, San Francisco, CA USA. RP Lersch, RA (reprint author), Lawrence Berkeley Lab, Div Life Sci, 1 Cyclotron Rd,MS 74-157, Berkeley, CA 94720 USA. RI Smida, Jan/P-2486-2014 NR 6 TC 0 Z9 0 U1 0 U2 0 PU HISTOCHEMICAL SOC INC PI SEATTLE PA UNIV WASHINGTON, DEPT BIOSTRUCTURE, BOX 357420, SEATTLE, WA 98195 USA SN 0022-1554 J9 J HISTOCHEM CYTOCHEM JI J. Histochem. Cytochem. PD JUL PY 2001 VL 49 IS 7 BP 925 EP 926 PG 2 WC Cell Biology SC Cell Biology GA 446LJ UT WOS:000169514500015 PM 11410619 ER PT J AU Lou, JL Marzari, R Verzillo, V Ferrero, F Pak, D Sheng, M Yang, CL Sblattero, D Bradbury, A AF Lou, JL Marzari, R Verzillo, V Ferrero, F Pak, D Sheng, M Yang, CL Sblattero, D Bradbury, A TI Antibodies in haystacks: how selection strategy influences the outcome of selection from molecular diversity libraries SO JOURNAL OF IMMUNOLOGICAL METHODS LA English DT Article DE phage antibodies; selection; libraries; molecular diversity ID PHAGE DISPLAY LIBRARIES; HUMAN MONOCLONAL-ANTIBODIES; HIGH-AFFINITY ANTIBODIES; SINGLE-CHAIN ANTIBODIES; RIBOSOME DISPLAY; IN-VITRO; PROTEIN; CELLS; FRAGMENTS; GENE AB Antibodies against most antigens can be isolated from high quality phage antibody libraries. However, not all antibodies binding a particular antigen are necessarily found when standard selections are performed. Here we investigate the effect of two different selection strategies on the isolation of antibodies against a number of different antigens, and find that these different strategies tend to select different antibodies, with little overlap between them. This indicates that the full diversity of these libraries is not tapped by a single selection strategy and that each selection strategy imposes different selective criteria in addition to that of antigen binding. To fully exploit such libraries, therefore, many different selection strategies should probably be employed for each antigen. The use of alternative strategies should be considered when selection apparently fails, or when the number of different antibodies recognizing an antigen needs to be maximised. Furthermore, the microtitre selection strategy developed is likely to prove useful in the application of phage antibody libraries to the human genome project, allowing the high throughput selection of antibodies against multiple antigens simultaneously. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Biosci Div, Los Alamos, NM 87545 USA. Univ Calif San Francisco, San Francisco Gen Hosp, Dept Anesthesia 3S50, San Francisco, CA 94143 USA. Univ Trieste, Dept Biol, Trieste, Italy. SISSA, I-34014 Trieste, Italy. Massachusetts Gen Hosp, Dept Neurobiol, Boston, MA 02114 USA. Univ Maryland Baltimore Cty, Dept Biochem & Mol Biol, Baltimore, MD 21228 USA. RP Bradbury, A (reprint author), Univ Calif Los Alamos Natl Lab, Biosci Div, MS M888, Los Alamos, NM 87545 USA. NR 41 TC 52 Z9 55 U1 1 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-1759 J9 J IMMUNOL METHODS JI J. Immunol. Methods PD JUL 1 PY 2001 VL 253 IS 1-2 BP 233 EP 242 DI 10.1016/S0022-1759(01)00385-4 PG 10 WC Biochemical Research Methods; Immunology SC Biochemistry & Molecular Biology; Immunology GA 441ZE UT WOS:000169258800021 PM 11384684 ER PT J AU Fthenakis, VM AF Fthenakis, VM TI A release of nitrogen oxides in Bogalusa, Louisiana and similarities of causation to the Bhopal MIC release SO JOURNAL OF LOSS PREVENTION IN THE PROCESS INDUSTRIES LA English DT Article DE accident; accident prevention; recurring causes; nitrogen tetroxide; Bogalusa AB The causes of a release of nitrogen oxides and nitric acid that occurred in Bogalusa, Louisiana in 1995 resembled those of the MIC release in Bhopal, India. The initiating event in both accidents was the entry of water into a storage vessel, which started a series of chemical reactions. An analysis of the underlying causes of these accidents shows some striking similarities (e.g. large quantities of a toxic chemical in storage, lack of instrumentation, inadequate mechanical systems, inadequate operating and maintenance procedures). Further, in both incidents a similar pattern of previous incidents, ignored warnings and ignored safety recommendations existed. Several layers of administrative and engineering options that could have prevented or mitigated these incidents are discussed. It is hoped that the identification of recurring root and contributing causes will help to prevent future accidents. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Brookhaven Natl Lab, Dept Environm Sci, Upton, NY 11973 USA. RP Fthenakis, VM (reprint author), Brookhaven Natl Lab, Dept Environm Sci, Upton, NY 11973 USA. NR 2 TC 1 Z9 1 U1 0 U2 2 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0950-4230 J9 J LOSS PREVENT PROC JI J. Loss Prev. Process Ind. PD JUL PY 2001 VL 14 IS 4 BP 245 EP 250 DI 10.1016/S0950-4230(01)00006-7 PG 6 WC Engineering, Chemical SC Engineering GA 433QL UT WOS:000168771200001 ER PT J AU Sakellariou, D Lesage, A Emsley, L AF Sakellariou, D Lesage, A Emsley, L TI Spectral editing in solid-state NMR using scalar multiple quantum filters SO JOURNAL OF MAGNETIC RESONANCE LA English DT Article DE solid-state NMR; spectral editing; J couplings; multiple-quantum filters; assignment ID NUCLEAR MAGNETIC-RESONANCE; PROTON-ENHANCED NMR; HIGH-RESOLUTION NMR; DILUTE SPINS; C-13 NMR; POLARIZATION TRANSFER; MAGIC-ANGLE; CPMAS NMR; SPECTROSCOPY; MULTIPLICITIES AB In this paper we describe the use of heteronuclear scalar couplings in solid-state NMR in order to generate multiple-quantum filtering (MQF) pulse sequences. These sequences can be used to edit CP/MAS spectra according to carbon multiplicity. Analytic expressions for the intensity of the MQF signals are obtained using the standard product operator formalism. Experiments that demonstrate the technique are shown in powder samples of camphor and a tripeptide. (C) 2001 Academic Press. C1 Ecole Normale Super Lyon, Lab Stereochim & Interact Mol, F-69364 Lyon, France. RP Sakellariou, D (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RI Emsley, Lyndon/C-6108-2008; Sakellariou, Dimitrios/F-2846-2010 OI Emsley, Lyndon/0000-0003-1360-2572; Sakellariou, Dimitrios/0000-0001-7424-5543 NR 47 TC 30 Z9 30 U1 1 U2 7 PU ACADEMIC PRESS INC 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 JUL PY 2001 VL 151 IS 1 BP 40 EP 47 DI 10.1006/jmre.2001.2338 PG 8 WC Biochemical Research Methods; Physics, Atomic, Molecular & Chemical; Spectroscopy SC Biochemistry & Molecular Biology; Physics; Spectroscopy GA 451VW UT WOS:000169823900005 PM 11444935 ER PT J AU Lipton, AS Sears, JA Ellis, PD AF Lipton, AS Sears, JA Ellis, PD TI A general strategy for the NMR observation of half-integer quadrupolar nuclei in dilute environments SO JOURNAL OF MAGNETIC RESONANCE LA English DT Article ID HIGH-RESOLUTION NMR; MAGNETIC-RESONANCE SPECTROSCOPY; SOLID-STATE NMR; ZN-67; CA-43; ANGLE; PROBE; K-39; METALLOPROTEINS; MAGNESIUM AB A general strategy for the observation of low gamma half-integer quadrupolar nuclides in biological systems is presented. The methodology combines low-temperature (4-100 K) techniques with cross-polarization (CP) experiments while employing a so-called Carr-Purcell-Meiboom-Gill spin-echo sequence (CPMG), This combined approach is termed CP/QCPMG. Also discussed are data processing issues that are unique to the induced signals that result from the QCPMG pulse sequence. Central to this strategy is the development of a stable low-temperature (4 to 250 K) NMR double-resonance probe. The probe is robust enough to handle multiple contact experiments and long acquisition periods with H-1 decoupling. This approach is illustrated with low-temperature solid-state Zn-67 and Mg-25 NMR CP/QCPMC experiments on model compounds. The conclusion reached is that the strategy affords sufficient sensitivity to examine Zn2+ and/or Mg2+ binding sites in metalloproteins. (C) 2001 Academic Press. C1 Pacific NW Natl Lab, WR Riley Environm Mol Sci Lab, Macromol Struct & Dynam Directorate, Richland, WA 99352 USA. RP Ellis, PD (reprint author), Pacific NW Natl Lab, WR Riley Environm Mol Sci Lab, Macromol Struct & Dynam Directorate, Richland, WA 99352 USA. FU NIGMS NIH HHS [GM26295F] NR 50 TC 79 Z9 80 U1 0 U2 26 PU ACADEMIC PRESS INC 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 JUL PY 2001 VL 151 IS 1 BP 48 EP 59 DI 10.1006/jmre.2001.2353 PG 12 WC Biochemical Research Methods; Physics, Atomic, Molecular & Chemical; Spectroscopy SC Biochemistry & Molecular Biology; Physics; Spectroscopy GA 451VW UT WOS:000169823900006 PM 11444936 ER PT J AU Reichert, D Bonagamba, TJ Schmidt-Rohr, K AF Reichert, D Bonagamba, TJ Schmidt-Rohr, K TI Slow-down of C-13 spin diffusion in organic solids by fast MAS: A CODEX NMR study SO JOURNAL OF MAGNETIC RESONANCE LA English DT Article ID CHEMICALLY EQUIVALENT NUCLEI; CENTERBAND-ONLY DETECTION; DIMENSIONAL EXCHANGE NMR; ROTATING SOLIDS; MAGNETIC-RESONANCE; DYNAMICS; SPECTROSCOPY; ZEOLITE; ODESSA; DISTANCES AB One- and two-dimensional C-13 exchange nuclear magnetic resonance experiments under magic-angle spinning (MAS) can provide detailed information on slow segmental reorientations and chemical exchange in organic solids, including polymers and proteins. However, observations of dynamics on the time scale of seconds or longer are hampered by the competing process of dipolar C-13 spin exchange (spin diffusion). In this Communication, we show that fast MAS can significantly slow down the dipolar spin exchange effect for unprotonated carbon sites. The exchange is measured quantitatively using the centerband-only detection of exchange technique, which enables the detection of exchange at any spinning speed, even in the absence of changes of isotropic chemical shifts. For chemically equivalent unprotonated C-13 sites, the dipolar spin exchange rate is found to decrease slightly less than proportionally with the sample-rotation frequency, between 8 and 28 kHz, In the same range, the dipolar spin exchange rate for a glassy polymer with an inhomogeneously broadened MAS line decreases by a factor of 10. For methylene groups, no or only a minor slow-down of the exchange rate is found, (C) 1001 Academic Press. C1 Univ Halle Wittenberg, FB Phys, D-06108 Halle, Germany. Univ Sao Paulo, Inst Fis Sao Carlos, BR-13560970 Sao Carlos, SP, Brazil. Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Dept Chem, Ames, IA 50011 USA. RP Schmidt-Rohr, K (reprint author), Univ Halle Wittenberg, FB Phys, D-06108 Halle, Germany. RI Bonagamba, Tito/A-2166-2008; Sao Carlos Institute of Physics, IFSC/USP/M-2664-2016 NR 42 TC 40 Z9 40 U1 1 U2 21 PU ACADEMIC PRESS INC 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 JUL PY 2001 VL 151 IS 1 BP 129 EP 135 DI 10.1006/jmre.2001.2337 PG 7 WC Biochemical Research Methods; Physics, Atomic, Molecular & Chemical; Spectroscopy SC Biochemistry & Molecular Biology; Physics; Spectroscopy GA 451VW UT WOS:000169823900017 PM 11444947 ER PT J AU von Zimmermann, M Nelson, CS Hill, JP Gibbs, D Blume, M Casa, D Keimer, B Murakami, Y Kao, CC Venkataraman, C Gog, T Tomioka, Y Tokura, Y AF von Zimmermann, M Nelson, CS Hill, JP Gibbs, D Blume, M Casa, D Keimer, B Murakami, Y Kao, CC Venkataraman, C Gog, T Tomioka, Y Tokura, Y TI X-ray resonant scattering studies of charge and orbital ordering in Pr1-xCaxMnO3 SO JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS LA English DT Article; Proceedings Paper CT Workshop on Applications of Synchrotron Light to Magnetic Materials CY AUG 14-16, 2000 CL LAB NACL LUZ SINCROTRON, CAMPINAS, BRAZIL HO LAB NACL LUZ SINCROTRON DE X-ray scattering; charge ordering; orbital ordering ID NEUTRON-DIFFRACTION; TRANSITION; MANGANITES; LA0.5SR1.5MNO4; PR0.7CA0.3MNO3; LAMNO3 AB We present the results of X-ray scattering studies of the charge and orbital ordering in the manganite series Pr1-xCaxMnO3 with x = 0.25, 0.4 and 0.5. The polarization and azimuthal dependence of the charge and orbital ordering in these compounds are characterized both in the resonant and nonresonant limits, and compared with the predictions of current theories. The results are qualitatively consistent with both cluster and LDA + U calculations of the electronic structure. (C) 2001 Elsevier Science B.V. All rights reserved. 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. Inst Mat Struct Sci High Energy Accelerator Res O, Photon Factory, Tsukuba, Ibaraki 3050801, Japan. Brookhaven Natl Lab, Natl Synchrotron Light Source Dept, Upton, NY 11973 USA. Argonne Natl Lab, CAT, CMC, Argonne, IL 60439 USA. JRCAT, Tsukuba, Ibaraki 3050033, Japan. Univ Tokyo, Dept Appl Phys, Tokyo 1130033, Japan. RP Gibbs, D (reprint author), Brookhaven Natl Lab, Dept Phys, Bldg 510-B,20 Penn St, Upton, NY 11973 USA. RI Tokura, Yoshinori/C-7352-2009; Casa, Diego/F-9060-2016; Hill, John/F-6549-2011 NR 32 TC 5 Z9 5 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-8853 J9 J MAGN MAGN MATER JI J. Magn. Magn. Mater. PD JUL PY 2001 VL 233 IS 1-2 BP 31 EP 37 DI 10.1016/S0304-8853(01)00221-9 PG 7 WC Materials Science, Multidisciplinary; Physics, Condensed Matter SC Materials Science; Physics GA 456UE UT WOS:000170100000006 ER PT J AU Longfield, MJ Wilmshurst, J Bouchenoire, L Cooper, MJ Mannix, D Lander, GH Bernhoeft, N Stunault, A Stirling, WG Pollmann, J Haskel, D Srajer, G AF Longfield, MJ Wilmshurst, J Bouchenoire, L Cooper, MJ Mannix, D Lander, GH Bernhoeft, N Stunault, A Stirling, WG Pollmann, J Haskel, D Srajer, G TI The use of resonant X-ray magnetic scattering to examine the magnetic phases in UAs-USe solid solutions SO JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS LA English DT Article; Proceedings Paper CT Workshop on Applications of Synchrotron Light to Magnetic Materials CY AUG 14-16, 2000 CL LAB NACL LUZ SINCROTRON, CAMPINAS, BRAZIL HO LAB NACL LUZ SINCROTRON DE X-ray scattering; resonant scattering; actinide AB Recent discoveries in the study of magnetism using synchrotron radiation are helping to elucidate the complex magnetism of the actinides. In this article we discuss the use of resonant X-ray magnetic scattering to investigate multi-k structures and the existence of induced magnetic moments in UAs-USe solid solutions. We present magnetic scattering experiments conducted at the ID20 and XMaS beamlines at the ESRF, Grenoble, France, and the ID-1 SRI-CAT beamline at the APS, Argonne, USA. (C) 2001 Elsevier Science B.V. All rights reserved. C1 European Synchrotron Radiat Facil, Pluo B3, XMaS CRG, F-38043 Grenoble, France. Univ Warwick, Dept Phys, Coventry CV4 7AL, W Midlands, England. Commiss European Communities, Joint Res Ctr, Inst Transuranium Elements, D-7500 Karlsruhe, Germany. CEA Grenoble, Dept Rech Fond Mat COndensee, F-38054 Grenoble, France. Univ Liverpool, Oliver Lodge Lab, Dept Phys, Liverpool L69 7ZE, Merseyside, England. Adv Photon Source, CAT, SRI, Argonne, IL USA. RP Longfield, MJ (reprint author), European Synchrotron Radiat Facil, Pluo B3, XMaS CRG, BP 220, F-38043 Grenoble, France. OI Mannix, Danny/0000-0002-7346-6894 NR 6 TC 2 Z9 2 U1 1 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-8853 J9 J MAGN MAGN MATER JI J. Magn. Magn. Mater. PD JUL PY 2001 VL 233 IS 1-2 BP 53 EP 56 DI 10.1016/S0304-8853(01)00226-8 PG 4 WC Materials Science, Multidisciplinary; Physics, Condensed Matter SC Materials Science; Physics GA 456UE UT WOS:000170100000009 ER PT J AU Keast, VJ Misra, A Kung, H Mitchell, TE AF Keast, VJ Misra, A Kung, H Mitchell, TE TI Compositional distributions in nanoscale metallic multilayers studied using x-ray mapping SO JOURNAL OF MATERIALS RESEARCH LA English DT Article ID ANALYTICAL ELECTRON-MICROSCOPE; NANOLAYERED COMPOSITES; CU; SEGREGATION; BOUNDARY; COPPER; PROBE AB At very small layer spacings (< -2 nm) in Cu-Nb and Cu-Cr multilayers the Cu forms a metastable body-centered-cubic (bcc) structure and the films exhibit interesting mechanical properties. No information about the miscibility of bcc Cu in Nb or Cr is available and it is not known whether the films remain compositionally discrete. X-ray mapping in the analytical electron microscope has been used to study the compositional distributions in these films and show that they do remain discrete down to a layer spacing of 1.8 nm. A simple model for the experimentally measured distribution has been used to show that the expected analytical resolution has been achieved and that it should be possible to map layers with a spacing of 0.8 nm. C1 Univ Cambridge, Dept Mat Sci & Met, Cambridge CB2 3QZ, England. Univ Calif Los Alamos Natl Lab, Mat Sci & Technol Div, Los Alamos, NM 87545 USA. RP Keast, VJ (reprint author), Univ Cambridge, Dept Mat Sci & Met, Pembroke St, Cambridge CB2 3QZ, England. RI Misra, Amit/H-1087-2012 NR 18 TC 4 Z9 4 U1 0 U2 0 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DR, WARRENDALE, PA 15086 USA SN 0884-2914 J9 J MATER RES JI J. Mater. Res. PD JUL PY 2001 VL 16 IS 7 BP 2032 EP 2038 DI 10.1557/JMR.2001.0278 PG 7 WC Materials Science, Multidisciplinary SC Materials Science GA 449DC UT WOS:000169668200024 ER PT J AU Swadener, JG Taljat, B Pharr, GM AF Swadener, JG Taljat, B Pharr, GM TI Measurement of residual stress by load and depth sensing indentation with spherical indenters SO JOURNAL OF MATERIALS RESEARCH LA English DT Article ID MECHANICAL-PROPERTIES; HARDNESS; NANOINDENTATION AB A new experimental technique is presented for making measurements of biaxial residual stress using load and depth sensing indentation (nanoindentation), The technique is based on spherical indentation, which, in certain deformation regimes, can be much more sensitive to residual stress than indentation with sharp pyramidal indenters like the Berkovich, Two different methods of analysis were developed: one requiring an independent measure of the material's yield strength and the other a reference specimen in the unstressed state or other known reference condition, Experiments conducted on aluminum alloys to which controlled biaxial bending stresses were applied showed that the methods are capable of measuring the residual stress to within 10-20% of the specimen yield stress, Because the methods do not require imaging of the hardness impressions, they are potentially useful for making localized measurements of residual stress, as in thin films or small volumes, or for characterization of point-to-point spatial variations of the surface stress. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. Univ Tennessee, Dept Mat Sci & Engn, Knoxville, TN 37996 USA. STEEL Grp, I-31054 Travois, Italy. Univ Ljubljana, Fac Mech Engn, Ljubljana 61000, Slovenia. RP Swadener, JG (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, POB 2008,MS 6093, Oak Ridge, TN 37831 USA. OI Swadener, John G/0000-0001-5493-3461 NR 31 TC 148 Z9 150 U1 4 U2 38 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 JUL PY 2001 VL 16 IS 7 BP 2091 EP 2102 DI 10.1557/JMR.2001.0286 PG 12 WC Materials Science, Multidisciplinary SC Materials Science GA 449DC UT WOS:000169668200032 ER PT J AU McClellan, KJ Chu, F Roper, JM Shindo, I AF McClellan, KJ Chu, F Roper, JM Shindo, I TI Room temperature single crystal elastic constants of boron carbide SO JOURNAL OF MATERIALS SCIENCE LA English DT Article AB Single crystals of the high temperature ceramic boron carbide have been synthesized by the optical floating zone method. Room temperature elastic constants of a carbon-deficient boron carbide single crystal have been measured using the resonant ultrasound spectroscopy technique. Based upon density measurements, the single crystal stoichiometry was specified as B5.6C. This crystal has room temperature single crystal elastic constants of c(11) = 542.81, c(33) = 534.54, c(13) = 63.51, c(12) = 130.59, and c(44) = 164.79 GPa, respectively. Analysis of Cauchy's relationships, Poisson's ratios, and elastic anisotropic factors for the single crystal elastic constants indicates that it is more strongly anisotropic in elasticity and interatomic bonding than most solids. Room temperature isotropic elastic moduli of boron carbide show that its bulk, shear and Young's moduli are substantially higher than those of most solids, so that boron carbide belongs to the so-called "strong solids". Its Poisson's ratio is significantly lower than that of most solids. (C) 2001 Kluwer Academic Publishers. C1 Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. RP McClellan, KJ (reprint author), Los Alamos Natl Lab, Div Mat Sci & Technol, Mail Stop G755, Los Alamos, NM 87545 USA. EM kmcclellan@lanl.gov NR 15 TC 28 Z9 29 U1 1 U2 11 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 JUL PY 2001 VL 36 IS 14 BP 3403 EP 3407 DI 10.1023/A:1017947625784 PG 5 WC Materials Science, Multidisciplinary SC Materials Science GA 451EV UT WOS:000169788900009 ER PT J AU Su, YJ Wang, H Porter, WD Lopez, ARDA Faber, KT AF Su, YJ Wang, H Porter, WD Lopez, ARDA Faber, KT TI Thermal conductivity and phase evolution of plasma-sprayed multilayer coatings SO JOURNAL OF MATERIALS SCIENCE LA English DT Article ID BARRIER COATINGS; TUNGSTEN COATINGS; DIFFUSIVITY; ALUMINA; MICROSTRUCTURE; ZIRCONIA; ZRO2 AB Multilayer coatings were prepared using small-particle plasma spray to investigate the effect of interfaces on thermal conductivity and phase stability. Monolithic and multilayer alumina and yttria partially-stabilized zirconia coatings, with 0, 3, 20, and 40 interfaces in 200-380 mum thick coatings were studied. Thermal conductivity was determined for the temperature range 25 degreesC to 1200 degreesC using the laser flash method and differential scanning calorimetry. Thermal conductivity of the multilayer coatings was accurately modeled by a series heat transfer equation, indicating that interfacial resistance plays a negligible role in heat transfer in the direction perpendicular to the coating plane. Powder X-ray diffraction results indicate that identical phase transitions occur in all the coatings. Independent of coating microstructure (i.e. layer thickness), as-sprayed gamma -Al2O3 transforms to alpha -Al2O3 after 100 hours at 1200 degreesC; as-sprayed metastable t'-ZrO2 converts to a mixture of t-ZrO2 and c-ZrO2 after 100 hours at 1300 degreesC. Thus, the results indicate that the interfaces do not aid in stabilizing the as-sprayed phases after prolonged severe heat treatments. (C) 2001 Kluwer Academic Publishers. C1 Northwestern Univ, Dept Mat Sci & Engn, Evanston, IL 60208 USA. Oak Ridge Natl Lab, High Temp Mat Lab, Oak Ridge, TN 37831 USA. Univ Sevilla, Dept Fis Mat Condensada, Seville, Spain. RP Su, YJ (reprint author), Northwestern Univ, Dept Mat Sci & Engn, Evanston, IL 60208 USA. RI Faber, Katherine/B-6741-2009; Wang, Hsin/A-1942-2013 OI Wang, Hsin/0000-0003-2426-9867 NR 35 TC 10 Z9 10 U1 0 U2 10 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 JUL PY 2001 VL 36 IS 14 BP 3511 EP 3518 DI 10.1023/A:1017932617123 PG 8 WC Materials Science, Multidisciplinary SC Materials Science GA 451EV UT WOS:000169788900022 ER PT J AU Wei, GW Wang, HX Kouri, DJ Papadakis, M Kakadiaris, IA Hoffman, DK AF Wei, GW Wang, HX Kouri, DJ Papadakis, M Kakadiaris, IA Hoffman, DK TI On the mathematical properties of Distributed Approximating Functionals SO JOURNAL OF MATHEMATICAL CHEMISTRY LA English DT Article DE Distributed Approximating Functionals (DAFs); wavelet generator; Gaussian function ID WAVELETS AB This work investigates some mathematical properties of the Distributed Approximating Functionals (DAFs). We prove that certain classes of DAFs yield Unity Approximations. Two distinct classes which serve as examples are the Hermite-DAFs and the Sinc-class DAFs. Detailed proofs are given. A wavelet generator is constructed using the Continuous Wavelet Transform with repect to the scale parameter. Taking the Gaussian function as the scaling function, a numerical experiment is carried out demonstrating the use of the resulting wavelet for edge detection. C1 Natl Univ Singapore, Dept Computat Sci, Singapore 129260, Singapore. Univ Houston, Dept Chem, Houston, TX 77204 USA. Univ Houston, Dept Phys, Houston, TX 77204 USA. Univ Houston, Dept Math, Houston, TX 77204 USA. Univ Houston, Dept Comp Sci, Houston, TX 77204 USA. Iowa State Univ, Dept Chem, Ames, IA 50011 USA. Iowa State Univ, Ames Lab, Ames, IA 50011 USA. RP Wei, GW (reprint author), Natl Univ Singapore, Dept Computat Sci, Singapore 129260, Singapore. RI Wei, Guowei /E-1852-2011; OI Kakadiaris, Ioannis/0000-0002-0591-1079 NR 15 TC 3 Z9 3 U1 0 U2 1 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0259-9791 J9 J MATH CHEM JI J. Math. Chem. PD JUL PY 2001 VL 30 IS 1 BP 83 EP 107 DI 10.1023/A:1013198218461 PG 25 WC Chemistry, Multidisciplinary; Mathematics, Interdisciplinary Applications SC Chemistry; Mathematics GA 516TN UT WOS:000173573000004 ER PT J AU Silverstein, E AF Silverstein, E TI Extended objects from warped compactifications of M theory SO JOURNAL OF MATHEMATICAL PHYSICS LA English DT Article ID ART.; SUPERGRAVITY AB We study the massive spectrum of fully wrapped branes in warped M-theory compactifications, including regimes where these states are parametrically lighter than the Planck scale or string scale. We show that many such states behave classically as extended objects in the noncompact directions in the sense that their mass grows with their size as measured along the Poincare slices making up the noncompact dimensions. On the other hand, these states can be quantized in a nontrivial regime: in particular, their spectrum of excitations in a limited regime can be obtained by a warped Kaluza-Klein reduction from ten dimensions. We briefly discuss scattering processes and loop effects involving these states, and also note the possibility of an exponential growth in the number of bound states of these objects as a function of energy. (C) 2001 American Institute of Physics. C1 Stanford Univ, Dept Phys, Stanford, CA 94305 USA. Stanford Univ, SLAC, Stanford, CA 94305 USA. RP Silverstein, E (reprint author), Stanford Univ, Dept Phys, Stanford, CA 94305 USA. NR 23 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0022-2488 J9 J MATH PHYS JI J. Math. Phys. PD JUL PY 2001 VL 42 IS 7 BP 3161 EP 3170 DI 10.1063/1.1373422 PG 10 WC Physics, Mathematical SC Physics GA 444NU UT WOS:000169406900025 ER PT J AU Mansur, LK Gabriel, TA Haines, JR Lousteau, DC AF Mansur, LK Gabriel, TA Haines, JR Lousteau, DC TI R&D for the Spallation Neutron Source mercury target SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 4th International Workshop on Spallation Matereials Technology (IWSMT-4) CY OCT 08-13, 2000 CL SCHRUNS, AUSTRIA SP Forschungszentrum Julich, Los Alamos Natl Lab, Oak Ridge Natl Lab, Paul Scherrer Inst ID HELIUM AB An overview of the research and development program for the Spallation Neutron Source (SNS) is presented. The materials-related efforts in target development are emphasized in order to provide a perspective for a number of specialized papers that are included in these proceedings. We give a brief introduction and historical sketch of the SNS project. Part of the materials R&D consists of calculations of radiation damage and of transmutation rates. He and H are considered to be the most important transmutation products. Radiation effects and Hg compatibility investigations make up the major part of the experimental effort. In the former, spallation irradiations are carried out in the LANSCE at Los Alamos National Laboratory and in the SINQ at the Paul Scherrer Institute. Irradiations that simulate aspects of a spallation environment are included to extend the parameter space of the spallation irradiations. The simulations are carried out at the low energy (MeV) accelerators of the TIF facility and at the HFIR reactor, both located at Oak Ridge National Laboratory. Irradiated specimens are tested for changes in mechanical properties and are characterized with respect to microstructural changes by transmission electron microscopy. The compatibility experiments cover both the effects of Hg on behavior in mechanical properties tests, and the effects of flowing Hg on mass transfer in target structural materials. The results of this extensive program of materials work indicate that the target design and materials performance will meet their intended service. Published by Elsevier Science B.V. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Mansur, LK (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. NR 31 TC 29 Z9 29 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD JUL PY 2001 VL 296 BP 1 EP 16 DI 10.1016/S0022-3115(01)00560-8 PG 16 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 456PV UT WOS:000170092200002 ER PT J AU Bauer, GS Dai, Y Mansur, LK Ullmaier, H Maloy, SA AF Bauer, GS Dai, Y Mansur, LK Ullmaier, H Maloy, SA TI Spallation materials technology 4 - Proceedings of the 4th International Workshop on Spallation Materials Technology (IWSMT-4) - Schruns, Austria - October 8-13, 2000 - Preface SO JOURNAL OF NUCLEAR MATERIALS LA English DT Editorial Material C1 Paul Scherrer Inst, Villigen, Switzerland. Oak Ridge Natl Lab, Oak Ridge, TN 37830 USA. Forschungszentrum Julich, Julich, Germany. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Bauer, GS (reprint author), Paul Scherrer Inst, Villigen, Switzerland. RI Maloy, Stuart/A-8672-2009 OI Maloy, Stuart/0000-0001-8037-1319 NR 0 TC 0 Z9 0 U1 0 U2 0 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 JUL PY 2001 VL 296 BP VII EP VII PG 1 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 456PV UT WOS:000170092200001 ER PT J AU Barnett, MH Wechsler, MS Dudziak, DJ Mansur, LK Murphy, BD AF Barnett, MH Wechsler, MS Dudziak, DJ Mansur, LK Murphy, BD TI Radiation damage to the 316 stainless steel target container vessel at SNS SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 4th International Workshop on Spallation Matereials Technology (IWSMT-4) CY OCT 08-13, 2000 CL SCHRUNS, AUSTRIA SP Forschungszentrum Julich, Los Alamos Natl Lab, Oak Ridge Natl Lab, Paul Scherrer Inst AB In the past, our calculations of radiation damage (concentrations of displacements, helium atoms, and hydrogen atoms) to the 316 stainless steel (316SS) container vessel at the spallation neutron source (SNS) mercury target dealt with the average damage rates in a volume at the nose of the vessel. This paper describes an attempt to improve the accuracy of estimates of the damage rates at the center of the proton beam where the damage rates are expected to be the highest. Four series of calculations (Series I-IV) were conducted to determine the damage rates within volumes (tally volumes) that varied systematically in location in the vessel. This permitted extrapolation to the rates at the tip of the vessel nose (Z = 0) and at the center of the proton beam (X = Y = 0) The total damage rates due to protons and neutrons were found to be: 36 dpa/yr, 1400 appmHe/yr, and 20000 appmH/yr. In addition, insight was gained into how the damage rates vary with position in the vessel nose and at locations further downstream in the vessel. (C) 2001 Elsevier Science B.V. All rights reserved. C1 N Carolina State Univ, Raleigh, NC 27695 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Wechsler, MS (reprint author), N Carolina State Univ, Raleigh, NC 27695 USA. NR 18 TC 16 Z9 16 U1 0 U2 1 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 JUL PY 2001 VL 296 BP 54 EP 60 DI 10.1016/S0022-3115(01)00499-8 PG 7 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 456PV UT WOS:000170092200006 ER PT J AU Zheng, Y Wechsler, MS Dudziak, DJ Hunn, JD Mansur, LK AF Zheng, Y Wechsler, MS Dudziak, DJ Hunn, JD Mansur, LK TI Simulation of the implantation of recoils and displacement production in the 316 stainless steel mercury-container vessel at SNS SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 4th International Workshop on Spallation Matereials Technology (IWSMT-4) CY OCT 08-13, 2000 CL SCHRUNS, AUSTRIA SP Forschungszentrum Julich, Los Alamos Natl Lab, Oak Ridge Natl Lab, Paul Scherrer Inst AB In this study, the focus is on the possible effect of mercury and transmuted atom recoils that are implanted into the wall of the stainless steel container vessel at SNS. Two computer codes were used: Los Alamos high energy transport (LAHET) and the stopping and range of ions in matter (SRIM). LAHET provided information of the energy distribution of the recoils upon bombardment. Also, SRIM simulated the transport of recoils through the mercury layer adjacent to the stainless steel wall and into the wall itself, and provided recoil and displacement concentration profiles in the wall. The calculated recoil and displacement concentrations in the near-surface region of the wall appear to be quite significant. The recoil and displacement concentrations per year at the surface are determined to be about 0.0015 recoil atoms/wall atom and about 17 dpa at the center of an incident proton beam. These concentrations fall to about one-half of the surface values at a penetration distance of about 0.1 mum, and the concentrations become negligibly small at 0.5 mum and beyond. (C) 2001 Elsevier Science B.V. All rights reserved. C1 N Carolina State Univ, Raleigh, NC 27695 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Wechsler, MS (reprint author), N Carolina State Univ, Raleigh, NC 27695 USA. NR 13 TC 0 Z9 0 U1 0 U2 0 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 JUL PY 2001 VL 296 BP 61 EP 65 DI 10.1016/S0022-3115(01)00500-1 PG 5 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 456PV UT WOS:000170092200007 ER PT J AU Garner, FA Oliver, BM Greenwood, LR James, MR Ferguson, PD Maloy, SA Sommer, WF AF Garner, FA Oliver, BM Greenwood, LR James, MR Ferguson, PD Maloy, SA Sommer, WF TI Determination of helium and hydrogen yield from measurements on pure metals and alloys irradiated by mixed high energy proton and spallation neutron spectra in LANSCE SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 4th International Workshop on Spallation Matereials Technology (IWSMT-4) CY OCT 08-13, 2000 CL SCHRUNS, AUSTRIA SP Forschungszentrum Julich, Los Alamos Natl Lab, Oak Ridge Natl Lab, Paul Scherrer Inst AB The confident design of accelerator-driven spallation neutron devices will require good estimates of the cross-sections for generation of helium and hydrogen in the mixed spectra of high energy protons and neutrons that will be experienced by the structural materials. Improved estimates of these cross-sections were derived from a series of irradiations that were conducted at relatively low temperatures (< 100 degreesC) in the Los Alamos Neutron Science Center (LANSCE) as part of the test program supporting the Accelerator Production of Tritium (APT) Program. In this irradiation campaign, a variety of candidate structural alloys and pure metal dosimeter foils were irradiated in various particle spectra, ranging from 800 MeV protons, to mixed energy distributions of both protons and spallation neutrons, and finally to distributions consisting primarily of high energy neutrons. At proton energies on the order of hundreds of MeV, exceptionally high levels of gas atoms are generated in all elemental constituents of typical iron-based and nickel-based structural alloys, with helium typically on the order of similar to 150 appm per dpa. and hydrogen at approximately a factor of 3-5 higher. Most of the gas production is due to proton and helium recoils from the proton beam interactions with the specimens, although gas and especially damage production from lower-energy spallation neutrons becomes increasingly significant at locations farther from the beam center. The results show that helium production rate per dpa by protons in elements typically found in structural alloys is relatively insensitive to elemental composition. The measured helium concentrations and the derived cross-sections are larger by about a factor of two, however, than those calculated using the LAHET code which was optimized for prediction of neutron/proton ratios in the target tungsten source rods of the APT test, Unlike helium, the retained hydrogen levels are somewhat sensitive to composition, reflecting primarily different levels of diffusional loss, but hydrogen is still retained at rather high concentrations, allowing a lower bound estimate of the hydrogen generation rates. (C) 2001 Elsevier Science BY. All rights reserved. C1 Pacific NW Natl Lab, Mat Resources Dept, Richland, WA 99352 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Garner, FA (reprint author), Pacific NW Natl Lab, Mat Resources Dept, 902 Battelle Blvd,MSIN P8-15, Richland, WA 99352 USA. RI Maloy, Stuart/A-8672-2009; Greenwood, Lawrence/H-9539-2016; OI Maloy, Stuart/0000-0001-8037-1319; Greenwood, Lawrence/0000-0001-6563-0650; Ferguson, Phillip/0000-0002-7661-4223 NR 18 TC 45 Z9 45 U1 1 U2 10 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 JUL PY 2001 VL 296 BP 66 EP 82 DI 10.1016/S0022-3115(01)00562-1 PG 17 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 456PV UT WOS:000170092200008 ER PT J AU Caturla, MJ de la Rubia, TD Victoria, M Corzine, RK James, MR Greene, GA AF Caturla, MJ de la Rubia, TD Victoria, M Corzine, RK James, MR Greene, GA TI Multiscale modeling of radiation damage: applications to damage production by GeV proton irradiation of Cu and W, and pulsed irradiation effects in Cu and Fe SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 4th International Workshop on Spallation Matereials Technology (IWSMT-4) CY OCT 08-13, 2000 CL SCHRUNS, AUSTRIA SP Forschungszentrum Julich, Los Alamos Natl Lab, Oak Ridge Natl Lab, Paul Scherrer Inst ID DISPLACEMENT CASCADES; COMPUTER-SIMULATION; MOLECULAR-DYNAMICS; METALS; EVOLUTION; FCC AB The damage accumulation in Cu and W is investigated using a multiscale modeling approach. The efficiency for defect production of displacement cascades is calculated using molecular dynamics (MD). The simulation uses the recoil spectra from spallation reactions of 1.1 and 1.9 GeV protons as calculated with the Los Alamos High Energy Transport (LAHET) nuclear transport code. The total number of defects produced under these irradiation conditions is obtained both from the NRT and MID approximations. The value for the change in electrical resistivity produced by the irradiation-induced defect microstructure is compared to experimental values obtained from irradiations with protons of the above energies, showing a better agreement for the lower irradiation energy. The damage evolution is simulated with kinetic Monte Carlo, where the inputs for the calculation are the results from MID previously obtained. A large recovery of the damage is found at room temperature as a result of the migration of interstitial clusters, single vacancies and small vacancy clusters to sinks such as dislocations. Finally the effects of pulsed irradiation have been analyzed in Cu. and Fe with similar simulation tools. The results indicate a clear influence of pulsing at I Hz, but not at higher frequencies. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Swiss Fed Inst Technol, Ctr Res Plasma Phys, Fus Mat Technol Div, CH-5232 Villigen, Switzerland. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. RP Victoria, M (reprint author), Swiss Fed Inst Technol, Ctr Res Plasma Phys, Fus Mat Technol Div, CH-5232 Villigen, Switzerland. RI Caturla, Maria /D-6241-2012 OI Caturla, Maria /0000-0002-4809-6553 NR 18 TC 32 Z9 32 U1 2 U2 17 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 JUL PY 2001 VL 296 BP 90 EP 100 DI 10.1016/S0022-3115(01)00569-4 PG 11 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 456PV UT WOS:000170092200010 ER PT J AU Sencer, BH Bond, GM Hamilton, ML Garner, FA Maloy, SA Sommer, WF AF Sencer, BH Bond, GM Hamilton, ML Garner, FA Maloy, SA Sommer, WF TI Microstructural origins of radiation-induced changes in mechanical properties of 316 L and 304 L austenitic stainless steels irradiated with mixed spectra of high-energy protons and spallation neutrons SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 4th International Workshop on Spallation Matereials Technology (IWSMT-4) CY OCT 08-13, 2000 CL SCHRUNS, AUSTRIA SP Forschungszentrum Julich, Los Alamos Natl Lab, Oak Ridge Natl Lab, Paul Scherrer Inst ID EVOLUTION AB A number of candidate alloys were exposed to a particle flux and spectrum at Los Alamos Neutron Science Center (LANSCE) that closely match the mixed high-energy proton/neutron spectra expected in accelerator production of tritium (APT) window and blanket applications. Austenitic stainless steels 316 L and 304 L are two of these candidate alloys possessing attractive strength and corrosion resistance for APT applications. This paper describes the dose dependence of the irradiation-induced microstructural evolution of SS 316 L and 304 L in the temperature range 30-60 degreesC and consequent changes in mechanical properties. It was observed that the microstructural evolution during irradiation was essentially identical in the two alloys, a behavior mirrored in their changes in mechanical properties. With one expection, it was possible to correlate all changes in mechanical properties with visible microstructural. features. A late-term second abrupt decrease in uniform elongation was not associated with visible microstructure, but is postulated to be a consequence of large levels of retained hydrogen measured in the specimens. In spite of large amounts of both helium and hydrogen retained, approaching I at.% at the highest exposures, no visible cavities were formed, indicating that the gas atoms were either in solution or in subresolvable clusters. Published by Elsevier Science B.V. C1 New Mexico Inst Min & Technol, Socorro, NM 87801 USA. Pacific NW Natl Lab, Mat Resources Dept, Richland, WA 99352 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Sencer, BH (reprint author), New Mexico Inst Min & Technol, Socorro, NM 87801 USA. RI Maloy, Stuart/A-8672-2009 OI Maloy, Stuart/0000-0001-8037-1319 NR 13 TC 12 Z9 12 U1 4 U2 10 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 JUL PY 2001 VL 296 BP 112 EP 118 DI 10.1016/S0022-3115(01)00512-8 PG 7 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 456PV UT WOS:000170092200012 ER PT J AU Maloy, SA James, MR Willcutt, G Sommer, WF Sokolov, M Snead, LL Hamilton, ML Garner, F AF Maloy, SA James, MR Willcutt, G Sommer, WF Sokolov, M Snead, LL Hamilton, ML Garner, F TI The mechanical properties of 316L/304L stainless steels, Alloy 718 and Mod 9Cr-1Mo after irradiation in a spallation environment SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 4th International Workshop on Spallation Matereials Technology (IWSMT-4) CY OCT 08-13, 2000 CL SCHRUNS, AUSTRIA SP Forschungszentrum Julich, Los Alamos Natl Lab, Oak Ridge Natl Lab, Paul Scherrer Inst AB The Accelerator Production of Tritium (APT) project proposes to use a 1.0 GeV, 100 mA proton beam to produce neutrons via spallation reactions in a tungsten target. The neutrons are multiplied and moderated in a lead/aluminum/water blanket and then captured in He-3 to form tritium. The materials in the target and blanket region are exposed to protons and neutrons with energies into the GeV range. The effect of irradiation on the tensile and fracture toughness properties of candidate APT materials, 316L and 304L stainless steel (annealed), modified (Mod) 9Cr-1Mo steel, and Alloy 718 (precipitation hardened), was measured on tensile and fracture toughness specimens irradiated at the Los Alamos Neutron Science Center accelerator, which operates at an energy of 800 MeV and a current of I mA. The irradiation temperatures ranged from 50 degreesC to 164 degreesC, prototypic of those expected in the APT target/blanket. The maximum achieved proton fluence was 4.5 x 10(21) p/cm(2) for the materials in the center of the beam. This maximum exposure translates to a dpa of 12 and the generation of 10000 appm H and 1000 appm He for the Type 304L stainless steel tensile specimens. Specimens were tested at the irradiation temperature of 50-164 degreesC. Less than I dpa of exposure reduced the uniform elongation of the Alloy 718 (precipitation hardened) and Mod 9Cr-1Mo to less than 2%. This same dose reduced the fracture toughness by 50%. Approximately 4 dpa of exposure was required to reduce the uniform elongation of the austenitic stainless steels (304L and 316L) to less than 2%. The yield stress of the austenitic steels increased to more than twice its non-irradiated value after less than I dpa. The fracture toughness reduced significantly by 4 dpa to similar to 100 MPa m(1/2). These results are discussed and compared with results of similar materials irradiated in fission reactor environments. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. Pacific NW Natl Lab, Richland, WA 99352 USA. RP Maloy, SA (reprint author), Univ Calif Los Alamos Natl Lab, MS-H809, Los Alamos, NM 87545 USA. RI Maloy, Stuart/A-8672-2009 OI Maloy, Stuart/0000-0001-8037-1319 NR 13 TC 72 Z9 75 U1 1 U2 25 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 JUL PY 2001 VL 296 BP 119 EP 128 DI 10.1016/S0022-3115(01)00514-1 PG 10 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 456PV UT WOS:000170092200013 ER PT J AU Farrell, K Byun, TS AF Farrell, K Byun, TS TI Tensile properties of candidate SNS target container materials after proton and neutron irradiation in the LANSCE accelerator SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 4th International Workshop on Spallation Matereials Technology (IWSMT-4) CY OCT 08-13, 2000 CL SCHRUNS, AUSTRIA SP Forschungszentrum Julich, Los Alamos Natl Lab, Oak Ridge Natl Lab, Paul Scherrer Inst ID STAINLESS-STEELS AB Tensile specimens of five austenitic stainless steels and two ferritic/martensitic (f/m) steels were irradiated under spallation conditions at temperatures between 60 degreesC and 164 degreesC to doses between 0.4 and I I dpa. The irradiations were performed at the Los Alamos Neutron Science Center (LANSCE) accelerator in a beam of 800 MeV protons and in the mixed spectrum of protons and spallation neutrons from a tungsten target. Tensile testing was done at room temperature at a crosshead speed of 0.005 mm/s, corresponding to a strain rate of 10(-3) s(-1). All materials showed considerable irradiation hardening and loss of ductility. For EC316 LN stainless steel, which is the recommended material for construction of the spallation neutron source (SNS) mercury target container and shroud, the yield strength (0.2% offset) was increased by a factor of three at 11 dpa. This steel retained a significant uniform elongation of 6%, as did the other austenitic steels. The two f/m steels entered plastic instability failures at strains less than 1% for all doses. Published by Elsevier Science B.V. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Farrell, K (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. NR 23 TC 46 Z9 47 U1 1 U2 5 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 JUL PY 2001 VL 296 BP 129 EP 138 DI 10.1016/S0022-3115(01)00515-3 PG 10 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 456PV UT WOS:000170092200014 ER PT J AU James, MR Maloy, SA Gac, FD Sommer, WF Chen, J Ullmaier, H AF James, MR Maloy, SA Gac, FD Sommer, WF Chen, J Ullmaier, H TI The mechanical properties of an Alloy 718 window after irradiation in a spallation environment SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 4th International Workshop on Spallation Matereials Technology (IWSMT-4) CY OCT 08-13, 2000 CL SCHRUNS, AUSTRIA SP Forschungszentrum Julich, Los Alamos Natl Lab, Oak Ridge Natl Lab, Paul Scherrer Inst AB A double-shelled Alloy 718 window was irradiated at the Los Alamos Neutron Science Center (LANSCE) with a I mA, 800 MeV proton beam to a maximum dose of 20 dpa at a calculated irradiation temperature of 400 degreesC. After irradiation, the window was visually inspected in hot cells at the Chemical and Metallurgical Research (CMR) facility at the Los Alamos National Laboratory (LANL) and cut into strips for analysis. Microhardness and optical metallography were performed at the LANL hot cells and tensile testing and gamma measurements were performed at Forschungszentrum Julich. The results of these analyses are presented in comparison with previous results obtained on similarly irradiated Alloy 718 components. A crack that occurred in-service was also examined and possible failure modes are discussed. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Forschungszentrum Julich, Projekt ESS, D-52425 Julich, Germany. RP James, MR (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663,MS H809, Los Alamos, NM 87545 USA. RI Maloy, Stuart/A-8672-2009 OI Maloy, Stuart/0000-0001-8037-1319 NR 11 TC 13 Z9 13 U1 0 U2 4 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 JUL PY 2001 VL 296 BP 139 EP 144 DI 10.1016/S0022-3115(01)00516-5 PG 6 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 456PV UT WOS:000170092200015 ER PT J AU Sencer, BH Bond, GM Garner, FA Hamilton, ML Maloy, SA Sommer, WF AF Sencer, BH Bond, GM Garner, FA Hamilton, ML Maloy, SA Sommer, WF TI Correlation of radiation-induced changes in mechanical properties and microstructural development of Alloy 718 irradiated with mixed spectra of high-energy protons and spallation neutrons SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 4th International Workshop on Spallation Matereials Technology (IWSMT-4) CY OCT 08-13, 2000 CL SCHRUNS, AUSTRIA SP Forschungszentrum Julich, Los Alamos Natl Lab, Oak Ridge Natl Lab, Paul Scherrer Inst AB Alloy 718 is a gamma ' (Ni-3(Al,Ti))-gamma " (Ni3Nb) hardenable superalloy with attractive strength, and corrosion resistance. This alloy is a candidate material for use in accelerator production of tritium (APT) target and blanket applications, where it would have to withstand low-temperature irradiation by high-energy protons and spallation neutrons. The existing data base, relevant to such irradiation conditions, is very limited. Alloy 718 has therefore been exposed to a particle flux and spectrum at the Los Alamos Neutron Science Center (LANSCE), closely matching those expected in the A-PT target and blanket applications. The yield stress of Alloy 718 increases with increasing dose up to similar to0.5 dpa, and then decreases with further increase in dose. The uniform elongation, however, drastically decreases with increasing dose at very low doses (<0.5 dpa), and does not recover when the alloy later softens somewhat. Transmission electron microscopy (TEM) investigation of Alloy 718 shows that superlattice spots corresponding to the age-hardening precipitate phases gamma ' and gamma " are lost from the diffraction patterns for Alloy 718 by only 0.6 dpa, the lowest proton-induced dose level achieved in this experiment. Examination of samples that were neutron irradiated to doses of only similar to0.1 dpa showed that precipitates are faintly visible in diffraction patterns but are rapidly becoming invisible. It is proposed that the gamma ' and gamma " first become disordered (by <0.6 dpa), but remain as solute-rich aggregates that still contribute to the hardness at relatively low dpa levels, and then are gradually dispersed at higher doses. Published by Elsevier Science B.V. C1 New Mexico Inst Min & Technol, Socorro, NM 87801 USA. Pacific NW Natl Lab, Mat Resources Dept, Richland, WA 99352 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Sencer, BH (reprint author), New Mexico Inst Min & Technol, Socorro, NM 87801 USA. RI Maloy, Stuart/A-8672-2009 OI Maloy, Stuart/0000-0001-8037-1319 NR 14 TC 18 Z9 19 U1 0 U2 9 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 JUL PY 2001 VL 296 BP 145 EP 154 DI 10.1016/S0022-3115(01)00517-7 PG 10 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 456PV UT WOS:000170092200016 ER PT J AU Dai, Y Jia, X Chen, JC Sommer, WF Victoria, M Bauer, GS AF Dai, Y Jia, X Chen, JC Sommer, WF Victoria, M Bauer, GS TI Microstructure of both as-irradiated and deformed 304L stainless steel irradiated with 800 MeV protons SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 4th International Workshop on Spallation Matereials Technology (IWSMT-4) CY OCT 08-13, 2000 CL SCHRUNS, AUSTRIA SP Forschungszentrum Julich, Los Alamos Natl Lab, Oak Ridge Natl Lab, Paul Scherrer Inst ID METALS AB A 304L stainless steel water degrader was irradiated with 800 MeV protons at Los Alamos Neutron Science Centre (LANSCE) up to 8.5 dpa at temperatures up to 250 degreesC. Tensile tests showed that hardening and embrittlement were induced in the material. In order to understand the irradiation hardening and embrittlement mechanism, the microstructure in both as-irradiated and deformed material has been studied. The results of TEM investigations show that in the as-irradiated material the main features are: (a) very dense small defect clusters, part of them can be resolved as stacking fault tetrahedra (SFT), with a mean size of about 1.6 run independent of irradiation dose; (b) large Frank loops. whose size increases with dose but whose density varies little with dose; (c) amorphization of precipitates; and (d) no observable helium bubbles or cavities. The main feature in the deformed material is the formation of twin lamellae and bundles of twin lamellae. In all of the four samples (0, 0.7, 3.4 and 6.8 dpa) studied, dense twin lamellae have been observed. The twin planes are {111}. Similar to channels observed in irradiated and deformed fcc pure metals, the original microstructures inside the twin lamellae, namely small clusters and Frank loops, have been removed. The width of the twin lamellae and their bundles varies from a few nanometers to more than 100 nm. The structure outside the twin lamellae is little changed. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Paul Scherrer Inst, Spallat Neutron Source Div, CH-5232 Villigen, Switzerland. Forschungszentrum Julich, Inst Festkorperforsch, D-52425 Julich, Germany. Univ Calif Los Alamos Natl Lab, Los Alamos Neutron Sci Ctr, Los Alamos, NM 87545 USA. PSI, Ecole Polytech Fed Lausanne, CRPP, CH-5232 Villigen, Switzerland. RP Dai, Y (reprint author), Paul Scherrer Inst, Spallat Neutron Source Div, CH-5232 Villigen, Switzerland. NR 22 TC 37 Z9 37 U1 3 U2 12 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 JUL PY 2001 VL 296 BP 174 EP 182 DI 10.1016/S0022-3115(01)00565-7 PG 9 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 456PV UT WOS:000170092200019 ER PT J AU Lee, EH Byun, TS Hunn, JD Farrell, K Mansur, LK AF Lee, EH Byun, TS Hunn, JD Farrell, K Mansur, LK TI Origin of hardening and deformation mechanisms in irradiated 316 LN austenitic stainless steel SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 4th International Workshop on Spallation Matereials Technology (IWSMT-4) CY OCT 08-13, 2000 CL SCHRUNS, AUSTRIA SP Forschungszentrum Julich, Los Alamos Natl Lab, Oak Ridge Natl Lab, Paul Scherrer Inst ID MICROSTRUCTURE; FCC; ALLOYS; COPPER AB The effects of displacement damage and trapped helium on deformation microstructures in AISI 316 LN austenitic stainless steel were studied by applying a newly developed disk bend method to specimens irradiated with 360 keV He ions at 200 degreesC. Radiation damage microstructures consisted of an intimate mix of black dots, dislocation loops, and very small helium filled cavities. In the unirradiated specimens, the deformation mode upon straining was planar glide with cross-slip. With increasing dose, cross-slip was progressively restricted. Correspondingly, deformation microstructure changed from dislocation network dominant to channeling dominant. The channel bands were composed of piled-up dislocations, stacking faults, and twinned layers. Published by Elsevier Science B.V. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37830 USA. RP Hunn, JD (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, POB 2008,Bldg 4500S,MS-6151, Oak Ridge, TN 37830 USA. NR 33 TC 37 Z9 37 U1 4 U2 12 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 JUL PY 2001 VL 296 BP 183 EP 191 DI 10.1016/S0022-3115(01)00566-9 PG 9 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 456PV UT WOS:000170092200020 ER PT J AU Hunn, JD Lee, EH Byun, TS Mansur, LK AF Hunn, JD Lee, EH Byun, TS Mansur, LK TI Ion-irradiation-induced hardening in Inconel 718 SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 4th International Workshop on Spallation Matereials Technology (IWSMT-4) CY OCT 08-13, 2000 CL SCHRUNS, AUSTRIA SP Forschungszentrum Julich, Los Alamos Natl Lab, Oak Ridge Natl Lab, Paul Scherrer Inst ID SPALLATION NEUTRON SOURCE; 800 MEV PROTONS; STAINLESS-STEEL; MECHANICAL-PROPERTIES; SOFT FILMS; HELIUM; NANOINDENTATION; MIGRATION; HARDNESS; NICKEL AB Inconel 718 is a material under consideration for areas in the target region of the spallation neutron source (SNS), now under construction at Oak Ridge National Laboratory (ORNL) in the US. In these positions., displacement damage from protons and neutrons will affect the mechanical properties. In addition, significant amounts of helium and hydrogen will build up in the material due to transmutation reactions. Nanoindentation measurements of solution-annealed (SA) Inconel 718 specimens, implanted with Fe-, He-, and H-ions to simulate SNS target radiation conditions, have shown that hardening occurs due to ion-induced displacement damage as well as due to the build-up of helium bubbles in the irradiated layer. Precipitation-hardened (PH) Inconel 718 also exhibited hardening by helium build-up but showed softening as a function of displacement damage due to dissolution of the gamma ' and gamma " precipitates. Published by Elsevier Science B.V. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Hunn, JD (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, POB 2008, Oak Ridge, TN 37831 USA. NR 25 TC 35 Z9 38 U1 2 U2 30 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 JUL PY 2001 VL 296 BP 203 EP 209 DI 10.1016/S0022-3115(01)00519-0 PG 7 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 456PV UT WOS:000170092200022 ER PT J AU Pawel, SJ DiStefano, JR Manneschmidt, ET AF Pawel, SJ DiStefano, JR Manneschmidt, ET TI Thermal gradient mass transfer of type 316L stainless steel and alloy 718 in flowing mercury SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 4th International Workshop on Spallation Matereials Technology (IWSMT-4) CY OCT 08-13, 2000 CL SCHRUNS, AUSTRIA SP Forschungszentrum Julich, Los Alamos Natl Lab, Oak Ridge Natl Lab, Paul Scherrer Inst AB Thermal convection loops (TCLs) fabricated from 316L stainless steel (SS) and containing mercury and a variety of 316L coupons representing variable surface conditions and heat treatments have been operated continuously for periods up to 5000 h. In each case, the maximum TCL temperature was about 305 degreesC, the minimum temperature about 240 degreesC, and the Hg velocity was constant at either 1.2 m/min or 5 m/min, depending on the TCL cross-section diameter. Wetting of 316L by Hg was somewhat sporadic and inconsistent, and was generally encouraged by steam cleaning and/or gold-coating of specimens prior to testing as well as relatively high exposure temperatures. Interaction of 316L and Hg was observed to generate a porous surface layer substantially depleted of Ni and Cr which resulted in transformation to ferrite, but the maximum penetration detected for all of the test conditions corresponded to only about 60-70 mum/yr, with far less penetration for most exposures. In limited testing, alloy 718 was found more resistant to wetting/attack than 316L. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Pawel, SJ (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, POB 2008, Oak Ridge, TN 37831 USA. NR 16 TC 11 Z9 11 U1 0 U2 2 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 JUL PY 2001 VL 296 BP 210 EP 218 DI 10.1016/S0022-3115(01)00520-7 PG 9 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 456PV UT WOS:000170092200023 ER PT J AU Strizak, JP DiStefano, JR Liaw, PK Tian, H AF Strizak, JP DiStefano, JR Liaw, PK Tian, H TI The effect of mercury on the fatigue behavior of 316 LN stainless steel SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 4th International Workshop on Spallation Matereials Technology (IWSMT-4) CY OCT 08-13, 2000 CL SCHRUNS, AUSTRIA SP Forschungszentrum Julich, Los Alamos Natl Lab, Oak Ridge Natl Lab, Paul Scherrer Inst AB Design of the mercury target system components for the Spallation Neutron Source (SNS) requires data on high- and low-cycle fatigue behavior, and the program in progress includes determining the effects of mercury on the fatigue behavior of type 316 LN stainless steel, the primary material of choice for the target vessel. Uniaxial, load-controlled fatigue tests with R = -1 and (minimum stress/maximum stress) have been conducted in air and mercury at room temperature employing constant amplitude, sinusoidal loading at frequencies from 0.1 to 700 Hz. Stress amplitude versus fatigue life (S-N curves) data at 10 Hz for both air and mercury show a sharp knee at approximately 1 million cycles indicating a fatigue endurance limit in either air or mercury around 240 Mpa. Mean stress (R = 0.1) lowers the endurance limit to 160 MPa. At relatively low frequency, both frequency and environment (mercury) had some impact on fatigue life of type 316 LN stainless steel at high-stress levels (i.e., stresses considerably above the apparent fatigue limit). Although testing at a high frequency of 700 Hz, showed a decrease in fatigue life in air compared with that at 10 Hz, a significant increase in specimen temperature was observed in air due to self-heating. No pronounced effects of waveform have yet been found, but data are limited. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Oak Ridge Natl Lab, Carbon & Insulat Mat Technol Grp, Oak Ridge, TN 37831 USA. Univ Tennessee, Knoxville, TN 37996 USA. RP Strizak, JP (reprint author), Oak Ridge Natl Lab, Carbon & Insulat Mat Technol Grp, Bethel Valley Rd,POB 2008, Oak Ridge, TN 37831 USA. NR 5 TC 14 Z9 14 U1 0 U2 0 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 JUL PY 2001 VL 296 BP 225 EP 230 DI 10.1016/S0022-3115(01)00594-3 PG 6 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 456PV UT WOS:000170092200025 ER PT J AU Bauer, GS Dai, Y Maloy, S Mansur, LK Ullmaier, H AF Bauer, GS Dai, Y Maloy, S Mansur, LK Ullmaier, H TI Summary of the Fourth International Workshop on Spallation Materials Technology (IWSMT-4) SO JOURNAL OF NUCLEAR MATERIALS LA English DT Editorial Material AB The Fourth International Workshop on Spallation Materials Technology (IWSMT-4) took place on 8-13 October in Schruns, Austria. The present volume contains the proceedings of this workshop. 53 scientists from Europe, USA and Japan presented 44 papers covering a wide range of topics including the status of spallation target R&D activities, effects of radiation damage, hydrogen, helium and other transmutation impurities in materials, particle transport calculations, heavy liquid metal corrosion and compatibility, and materials engineering. The main progress, with an emphasis on materials technology in different projects, namely the US Spallation Neutron Source (SNS), the European Spallation Source (ESS), the Japanese Spallation Neutron Source (JSNS), the Swiss Spallation Neutron Source (SINQ) and the US Accelerator Production of Tritium facility (APT) was overviewed. Progress from the European TECLA and SPIRE programs was described. The achievements of investigations in the last two years on mechanical properties and microstructures of materials under high-energy proton (spallation), neutron and low energy ion irradiations were reported. The latest results from studies on corrosion and embrittlement effects of heavy liquid metals (Hg, Pb-Bi and Pb) were presented. Some critical issues of liquid metal technology related to accelerator driven systems (ADS), e.g. oxygen control and oxygen measurements were discussed. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Paul Scherrer Inst, Spallat Source DIv, CH-5232 Villigen, Switzerland. Los Alamos Natl Lab, APT, TPO, Los Alamos, NM 87545 USA. Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. Forschungszentrum Julich, ESS Project, D-52425 Julich, Germany. RP Dai, Y (reprint author), Paul Scherrer Inst, Spallat Source DIv, CH-5232 Villigen, Switzerland. EM yong.dai@psi.ch NR 0 TC 3 Z9 3 U1 0 U2 6 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 JUL PY 2001 VL 296 BP 321 EP 325 DI 10.1016/S0022-3115(01)00568-2 PG 5 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 456PV UT WOS:000170092200039 ER PT J AU Feinendegen, LE Pollycove, M AF Feinendegen, LE Pollycove, M TI Biologic responses to low doses of ionizing radiation: Detriment versus hormesis Part1. Dose responses of cells and tissues SO JOURNAL OF NUCLEAR MEDICINE LA English DT Editorial Material ID EXPOSURE AB As early, as 1898 studies in radiobiology found that irradiated algae grew move quickly than nonirradiated controls. Physicians, the public, and research scientists evinced considerable interest in the possible beneficial effects of low levels of radiation. Such enthusiasms were soon dampened by reports of deaths and severe injury from lar ge amounts of radiation. After Herman Muller's 1928 publication on genetic damage in fruitflies, radiation became associated with chromosome damage. Data published in the 1930, 1940s, and 1950s, however, suggested that small amounts of radiation might be beneficial to cellular growth and repair a process dubbed "hormesis." Marshall Brucer; one of the originators of nuclear medicine applications, believed that this data had merit and warranted further investigation. By the 1950s, M,hat Brucer called "radiation hysteria " and the evolution of government support for radiation protection programs and personnel had institutionalized the concept of a linear no-close threshold - the notion that there is no lower limit to the amount of radiation that causes short- or long-term damage. As Brucer noted acerbically in a 1987 retrospective on hormesis, "Health physicists soon learned that their livelihood depended on scaring the pants off Congress." Studies have continued to yield data that support possible beneficial effects of low levels of radiation, but these have gone largely unremarked in the medical literature. Interest in radiation hormesis has grown in the East 5-10 years, however As recently as May 20, the Washington Post included a small article indicating that radiation hormesis deserves additional investigation. In this first of a two-part special contribution to Newsline, Ludwig Feinendegen and Myron Pollycove present current basic research data supporting radiation hormesis. Both authors believe that such data is often ignored in the face of a persistent and enduring scientific adherence to the linens no-dose threshold The authors suggest that a reassessment of this data is overdue and could have striking implications for the future practice of nuclear medicine. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. US Nucl Regulatory Commiss, Bethesda, MD USA. RP Feinendegen, LE (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. NR 20 TC 41 Z9 44 U1 1 U2 8 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 JUL PY 2001 VL 42 IS 7 BP 17N EP + PG 7 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 447QB UT WOS:000169583000004 PM 11441881 ER PT J AU Pavlishin, IV Dyublov, AA Meshkovskii, IK Ben-Zvi, I Pogrorel'skii, I AF Pavlishin, IV Dyublov, AA Meshkovskii, IK Ben-Zvi, I Pogrorel'skii, I TI Gain of a high-pressure TE CO2-laser amplifier with a large aperture SO JOURNAL OF OPTICAL TECHNOLOGY LA English DT Article AB A stable discharge has been obtained for the first time in a large-aperture TE CO2-laser amplifier with a pressure of the working mixture of 10 atm, and its gain has been studied. Results of studies of the gain of the laser amplifier with an 85 x 100-mm aperture in the pressure range of the working mixture of 5-10 atm are presented. (C) 2001 The Optical Society of America. C1 Tech Univ, St Petersburg Inst Precis Mech & Opt, St Petersburg, Russia. Brookhaven Natl Lab, New York, NY USA. RP Pavlishin, IV (reprint author), Tech Univ, St Petersburg Inst Precis Mech & Opt, St Petersburg, Russia. NR 14 TC 0 Z9 0 U1 0 U2 0 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1070-9762 J9 J OPT TECHNOL+ JI J. Opt. Technol. PD JUL PY 2001 VL 68 IS 7 BP 467 EP 470 DI 10.1364/JOT.68.000467 PG 4 WC Optics SC Optics GA 461BH UT WOS:000170344700003 ER PT J AU Ghosh, S Dickstein, R Knight, TJ Langston-Unkefer, PJ AF Ghosh, S Dickstein, R Knight, TJ Langston-Unkefer, PJ TI Interactions between Pseudomonas syringae pv. tabaci and two rhizosphere hosts, Medicago sativa and Avena sativa SO JOURNAL OF PLANT BIOCHEMISTRY AND BIOTECHNOLOGY LA English DT Article DE Avena sativa; glutamine synthetase; Medicago sativa; Pseudomonas syringae pv. tabaci; rhizosphere; Sinorhizobium meliloti; tabtoxinine-beta-lactam ID TABTOXININE-BETA-LACTAM; GLUTAMINE-SYNTHETASE GENES; NODULE DEVELOPMENT; SELF-PROTECTION; TOXIN; FIXATION; ROOTS AB The interactions between Pseudomonas syringae pv. tabaci and either nodulating alfalfa (Medicago sativa) or oat (Avena sativa) seedlings were examined to further our understanding of this rhizosphere association. P. syringae pv. tabaci produces and releases a toxin, tabtoxinine-beta -lactam (TOL), that inactivates glutamine synthetase (GS). Sinorhizobium, meliloti grew well in the presence of T betaL in culture and on alfalfa roots. The alfalfa symbiont, S. meliloti, and its bacteroids contained T betaL-sensitive glutamine synthetases and T betaL detoxifying-beta -lactamase. The GS of alfalfa leaves is also sensitive to T betaL, but GS activity was unaffected in infested plants. Toxin production was apparently suppressed in the alfalfa and nitrate-fed oat rhizospheres since these plants survived and retained significant amounts of leaf GS activity. The water-soluble extracts of these rhizospheres inhibited T betaL production in culture and the inhibition was correlated with the amount of reduced nitrogen present. Furthermore, representative mixtures of pure ammonium and amino acids inhibited T betaL production in culture in a concentration dependent manner. Thus, a bi-directional interaction occurs between the nitrogen metabolism of alfalfa and oat and T betaL production by P. syringae pv. tabaci. C1 Dominican Univ Calif, Dept Nat Sci & Math, San Rafael, CA 94901 USA. Univ N Texas, Dept Biol Sci, Denton, TX 76203 USA. Univ So Maine, Dept Biol Sci, Portland, ME 04103 USA. Los Alamos Natl Lab, Div Isotope & Nucl Chem, Los Alamos, NM 87545 USA. RP Ghosh, S (reprint author), Dominican Univ Calif, Dept Nat Sci & Math, San Rafael, CA 94901 USA. NR 32 TC 1 Z9 1 U1 1 U2 2 PU SOC PLANT BIOCHEM BIOTECH PI NEW DELHI PA DIV BIOCHEM, INDIAN AGRICULTURAL RES INST, NEW DELHI 110 012, INDIA SN 0971-7811 J9 J PLANT BIOCHEM BIOT JI J. Plant Biochem. Biotechnol. PD JUL PY 2001 VL 10 IS 2 BP 91 EP 99 PG 9 WC Biochemistry & Molecular Biology; Plant Sciences SC Biochemistry & Molecular Biology; Plant Sciences GA 475MV UT WOS:000171169000002 ER PT J AU Thackeray, MM AF Thackeray, MM TI From gems to lithium battery electrodes: the significance of the diamond, ruby (sapphire), spinel and peridot structures SO JOURNAL OF POWER SOURCES LA English DT Article; Proceedings Paper CT 10th International Meeting on Lithium Batteries CY MAY 28-JUN 02, 2000 CL COMO, ITALY DE lithium batteries; gems; intermetallic compounds ID INSERTION ELECTRODE AB The materials used for the negative and positive electrodes of rechargeable "lithium-ion" batteries have host structures that can accommodate and release lithium over a wide compositional range. In these batteries, carbon and intermetallic compounds have been widely exploited as the negative electrodes, and transition metal oxides as the positive electrodes. For a lithium-ion battery to perform adequately, the structural integrity of the electrode host structures must be maintained throughout discharge and charge for many hundreds of cycles. Nature provides many examples of stable compounds that can be produced under variable conditions of temperature and pressure. As such, the mineral world can be used as a guide for the selection of materials in technological applications. This paper highlights the structural relationships that exist between precious and semi-precious gems such as diamond, ruby (sapphire), spinel and peridot and insertion electrodes for lithium batteries. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Argonne Natl Lab, Div Chem Technol, Electrochem Technol Program, Argonne, IL 60439 USA. RP Thackeray, MM (reprint author), Argonne Natl Lab, Div Chem Technol, Electrochem Technol Program, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 11 TC 4 Z9 4 U1 1 U2 3 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 JUL PY 2001 VL 97-8 SI SI BP 7 EP 12 DI 10.1016/S0378-7753(01)00503-1 PG 6 WC Chemistry, Physical; Electrochemistry; Energy & Fuels; Materials Science, Multidisciplinary SC Chemistry; Electrochemistry; Energy & Fuels; Materials Science GA 452AY UT WOS:000169836000003 ER PT J AU Kong, F Kostecki, R Nadeau, G Song, X Zaghib, K Kinoshita, K McLarnon, F AF Kong, F Kostecki, R Nadeau, G Song, X Zaghib, K Kinoshita, K McLarnon, F TI In situ studies of SEI formation SO JOURNAL OF POWER SOURCES LA English DT Article; Proceedings Paper CT 10th International Meeting on Lithium Batteries CY MAY 28-JUN 02, 2000 CL COMO, ITALY DE carbon; SEI layer; ellipsometry; Raman spectroscopy; Li-ion batteries ID LI-ION BATTERIES; SURFACE-CHEMISTRY; INTERCALATION ANODES; ELECTROLYTE SYSTEMS; PYROLYTIC-GRAPHITE; RAMAN-SPECTROSCOPY; CARBON ELECTRODES; PERFORMANCE; ELLIPSOMETRY; FILMS AB Electrolyte decomposition and the formation of a solid electrolyte interphase (SEI) layer occur during the initial charge/discharge cycles of carbon in electrolytes used in Li-ion batteries. This paper describes our approach to characterize the formation of SEI layers on various carbonaceous materials by in situ ellipsometry, Five types of carbon samples (carbon films on glass, pyrolyzed photoresist on silicon, highly oriented pyrolytic graphite and natural graphite) with specular surfaces were characterized by Raman spectroscopy and in situ ellipsometry/ electrochemical studies in ethylene carbonate-dimethyl carbonate containing a lithium salt. Raman spectroscopy showed that the carbons films deposited on glass contain broad overlapping peaks from 900 to 1700 cm(-1), which is indicative of the highly disordered nature of the carbon films. Changes in the ellipsometric parameters, Delta and psi, were correlated with the formation of the SEI layer during the initial charge intercalation) process. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Inst Rech Hydro Quebec, Varennes, PQ J3X 1S1, Canada. RP McLarnon, F (reprint author), Lawrence Berkeley Lab, 1 Cyclotron Rd, Berkeley, CA 94720 USA. NR 29 TC 72 Z9 75 U1 13 U2 148 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 JUL PY 2001 VL 97-8 SI SI BP 58 EP 66 DI 10.1016/S0378-7753(01)00588-2 PG 9 WC Chemistry, Physical; Electrochemistry; Energy & Fuels; Materials Science, Multidisciplinary SC Chemistry; Electrochemistry; Energy & Fuels; Materials Science GA 452AY UT WOS:000169836000012 ER PT J AU Zaghib, K Nadeau, G Kinoshita, K AF Zaghib, K Nadeau, G Kinoshita, K TI Influence of edge and basal plane sites on the electrochemical behavior of flake-like natural graphite for Li-ion batteries SO JOURNAL OF POWER SOURCES LA English DT Article; Proceedings Paper CT 10th International Meeting on Lithium Batteries CY MAY 28-JUN 02, 2000 CL COMO, ITALY DE irreversible capacity loss (ICL); X-ray diffraction (XRD) analysis; Coulomb efficiency (CE) ID IRREVERSIBLE CAPACITY; LITHIUM INTERCALATION; CARBONS; ANODE; CELLS AB The irreversible capacity loss (ICL) that is observed with carbons in Li-ion batteries is associated with electrolyte decomposition. In this paper, we present the results of an analysis to illustrate the role that the edge and basal plane sites play on the ICL and first-cycle coulomb efficiency of flake-like natural graphite. A model of an ideal graphite particle, which is depicted as an ideal prismatic structure, is used to develop an understanding of the correlation of the fraction of edge sites and particle size for flake-like and cube structures. In the case of flake-like graphite, thin flakes have higher surface area and higher ICL than thicker flakes, even though the fraction of edge sites is lower. On the other hand, the cube structure has a high fraction of edge sites but a low ICL and low surface area. The analysis presented here suggests that the particle morphology and the surface area associated with the edge and basal plane sites play a significant role in the electrochemical performance of graphite in Li-ion batteries. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Inst Rech Hydro Quebec, Varennes, PQ J3X 1S1, Canada. Univ Calif Berkeley, Lawrence Berkeley Lab, Environm Energy Technol Div, Berkeley, CA 94720 USA. RP Zaghib, K (reprint author), Inst Rech Hydro Quebec, 1800 Boul Lionel Boulet, Varennes, PQ J3X 1S1, Canada. NR 17 TC 19 Z9 19 U1 1 U2 21 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 JUL PY 2001 VL 97-8 SI SI BP 97 EP 103 DI 10.1016/S0378-7753(01)00596-1 PG 7 WC Chemistry, Physical; Electrochemistry; Energy & Fuels; Materials Science, Multidisciplinary SC Chemistry; Electrochemistry; Energy & Fuels; Materials Science GA 452AY UT WOS:000169836000020 ER PT J AU Vaughey, JT Johnson, CS Kropf, AJ Benedek, R Thackeray, MM Tostmann, H Sarakonsri, T Hackney, S Fransson, L Edstrom, K Thomas, JO AF Vaughey, JT Johnson, CS Kropf, AJ Benedek, R Thackeray, MM Tostmann, H Sarakonsri, T Hackney, S Fransson, L Edstrom, K Thomas, JO TI Structural and mechanistic features of intermetallic materials for lithium batteries SO JOURNAL OF POWER SOURCES LA English DT Article; Proceedings Paper CT 10th International Meeting on Lithium Batteries CY MAY 28-JUN 02, 2000 CL COMO, ITALY DE lithium-ion battery; intermetallic; anode; indium antimonide ID ION BATTERIES; INSERTION ELECTRODES; LI; SYSTEM; ANODES AB An anode: system based on intermetallic phases with a zinc-blende-type structure (InSb, GaSb and AlSb) has been studied for Lithium-ion batteries, The compound, InSb, in particular, cycles well between 1.2 and 0.5 V. After an initial "conditioning" cycle, a mechanism involving lithium insertion into an open framework structure followed by indium extrusion in the potential range 1.2-0.7 V, appears to dominate; between 0.7 and 0.5 V, a more complex mechanism occurs involving indium extrusion from a stable fee Sb anion array and subsequent lithiation of the extruded indium, In situ X-ray diffraction and extended X-ray analysis fine structure (EXAFS) data were obtained over the voltage window 1.2-0.5 V, where a rechargeable capacity of 300 mAh/g is achievable. The results indicate that after the "conditioning" reaction a LiyIn1-ySb zinc-blende framework, in which Li atoms partially substitute for In, is responsible for the good cycling behavior of the cells. Isostructural AlSb and GaSb electrodes provide inferior electrochemical capacities. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Argonne Natl Lab, Div Chem Technol, Electrochem Technol Program, Argonne, IL 60439 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Univ Florida, Adv Photon Source, MRCAT, ANL, Gainesville, FL 32611 USA. Michigan Technol Univ, Dept Met & Mat Engn, Houghton, MI 49931 USA. Uppsala Univ, Angstrom Lab, SE-75121 Uppsala, Sweden. RP Thackeray, MM (reprint author), Argonne Natl Lab, Div Chem Technol, Electrochem Technol Program, 9700 S Cass Ave, Argonne, IL 60439 USA. RI ID, MRCAT/G-7586-2011; Kropf, Arthur/B-8665-2015; OI Vaughey, John/0000-0002-2556-6129; Edstroem, Kristina/0000-0003-4440-2952 NR 16 TC 48 Z9 48 U1 6 U2 26 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 JUL PY 2001 VL 97-8 SI SI BP 194 EP 197 DI 10.1016/S0378-7753(01)00618-8 PG 4 WC Chemistry, Physical; Electrochemistry; Energy & Fuels; Materials Science, Multidisciplinary SC Chemistry; Electrochemistry; Energy & Fuels; Materials Science GA 452AY UT WOS:000169836000043 ER PT J AU Benedek, R Vaughey, JT Thackeray, MM Yang, LH Prasad, R AF Benedek, R Vaughey, JT Thackeray, MM Yang, LH Prasad, R TI First-principles calculations for Li insertion into InSb SO JOURNAL OF POWER SOURCES LA English DT Article; Proceedings Paper CT 10th International Meeting on Lithium Batteries CY MAY 28-JUN 02, 2000 CL COMO, ITALY DE first-principles calculations; Li insertion; intermetallic electrode AB First-principles calculations are presented for the zinc-blende structure compound InSb, a candidate anode material for Li batteries. The atomic structure of InSb during Li insertion is discussed in the light of local density functional theory calculations based on plane-wave pseudopotential and linear muffin tin orbital methods. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Argonne Natl Lab, Electrochem Technol Program, Argonne, IL 60439 USA. Univ Calif Lawrence Livermore Natl Lab, Condensed Matter Phys Div, Livermore, CA 94551 USA. Indian Inst Technol, Dept Phys, Kanpur 208016, Uttar Pradesh, India. RP Benedek, R (reprint author), Argonne Natl Lab, Electrochem Technol Program, Argonne, IL 60439 USA. OI Vaughey, John/0000-0002-2556-6129 NR 11 TC 9 Z9 9 U1 0 U2 2 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 JUL PY 2001 VL 97-8 SI SI BP 201 EP 203 DI 10.1016/S0378-7753(01)00541-9 PG 3 WC Chemistry, Physical; Electrochemistry; Energy & Fuels; Materials Science, Multidisciplinary SC Chemistry; Electrochemistry; Energy & Fuels; Materials Science GA 452AY UT WOS:000169836000045 ER PT J AU Sun, X Yang, XQ McBreen, J Gao, Y Yakovleva, MV Xing, XK Daroux, ML AF Sun, X Yang, XQ McBreen, J Gao, Y Yakovleva, MV Xing, XK Daroux, ML TI New phases and phase transitions observed in over-charged states of LiCoO2-based cathode materials SO JOURNAL OF POWER SOURCES LA English DT Article; Proceedings Paper CT 10th International Meeting on Lithium Batteries CY MAY 28-JUN 02, 2000 CL COMO, ITALY DE LiCoO2-based cathode materials; phase transition; thermal stability; lithium batteries ID X-RAY-DIFFRACTION; LIXCOO2 AB Using synchrotron-based in situ X-ray diffraction, the structural changes of LiCoO2, LiCo0.5Ni0.5O2, and LiNi0.65Co0.25Mg0.25Ti0.05O2 cathode materials during charge in the voltage range of 3.5 to 5.2 V have been studied. When a LiCoO2 cathode was charged above 4.5 V, a new intermediate phase O1a was observed, before the terminal phase O1 was formed around 4.8 V. In the X-ray diffraction spectra for LiCo0.5Ni0.5O2 and LiNi0.65Co0.25Mg0.05Ti0.05O2 cathode materials, Bragg peaks representing the O1 structure were also observed. The amounts of O1 structure formed at the end of charge (5.2 V for LiNi0.65Co0.25Mg0.05Ti0.05O2 and 5.0 V for LiCo0.5Ni0.5O2) were increased with increasing Co content. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. FMC Corp, Princeton, NJ 08543 USA. Gould Elect Inc, Eastlake, OH 44095 USA. RP Yang, XQ (reprint author), Brookhaven Natl Lab, Bldg 480, Upton, NY 11973 USA. NR 6 TC 22 Z9 25 U1 4 U2 24 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 JUL PY 2001 VL 97-8 SI SI BP 274 EP 276 DI 10.1016/S0378-7753(01)00512-2 PG 3 WC Chemistry, Physical; Electrochemistry; Energy & Fuels; Materials Science, Multidisciplinary SC Chemistry; Electrochemistry; Energy & Fuels; Materials Science GA 452AY UT WOS:000169836000065 ER PT J AU Gover, RKB Kanno, R Mitchell, BJ Hirano, A Kawamoto, Y AF Gover, RKB Kanno, R Mitchell, BJ Hirano, A Kawamoto, Y TI The role of nickel content on the structure and electrochemical properties of Li-x(NiyCo1-y)O-2 SO JOURNAL OF POWER SOURCES LA English DT Article; Proceedings Paper CT 10th International Meeting on Lithium Batteries CY MAY 28-JUN 02, 2000 CL COMO, ITALY DE X-ray diffraction; structure analysis; charge/discharge properties ID LINIO2 AB Samples have, been prepared with nominal composition Li-x(NiyCo1-y)O-2 (x approximate to 1.25, y = 0.7-1.0) with the structures being examined using Rietveld analysis of X-ray diffraction data. Rietveld analysis shows that the samples prepared with y = 0.70 and 0.75 have no Ni present on the 3a Li site, with all other samples showing a small degree of nonstoichiometry. Structural analysis of the 3b Ni + Co occupancy also suggests the possibility of 3b site disorder, which is in agreement with the results of previous studies. Charge/discharge measurements show an increase in discharge capacity with increasing Ni content, which suggests cobalt plays a very small part in the electrochemical capacities of these phases using the current voltage Limits. Samples with y = 0.75, 0.8 and 0.85 were found to have Very high efficiencies over a number of cycles, typically > 99% over 15 cycles. Samples prepared with y = 0.85 and 0.90 show evidence of a phase change which resembles that seen for LiNiO2. This would suggest that the stabilizing effects of Co in Li-x(NiyCo1-y)O-2 is lost when y greater than or equal to 0.85. Therefore, these particular compositions are probably not suitable for use in Li ion cells. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Kobe Univ, Dept Chem, Nada Ku, Kobe, Hyogo 6578501, Japan. Argonne Natl Lab, Intense Pulsed Neutron Source, Argonne, IL 60439 USA. RP Kanno, R (reprint author), Kobe Univ, Dept Chem, Nada Ku, 1-1 Rokko Dai, Kobe, Hyogo 6578501, Japan. EM kanno@kobe-u.ac.jp NR 19 TC 20 Z9 23 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0378-7753 EI 1873-2755 J9 J POWER SOURCES JI J. Power Sources PD JUL PY 2001 VL 97-8 SI SI BP 316 EP 320 DI 10.1016/S0378-7753(01)00623-1 PG 5 WC Chemistry, Physical; Electrochemistry; Energy & Fuels; Materials Science, Multidisciplinary SC Chemistry; Electrochemistry; Energy & Fuels; Materials Science GA 452AY UT WOS:000169836000075 ER PT J AU Johnson, CS Thackeray, MM AF Johnson, CS Thackeray, MM TI Ammonia- and lithia-doped manganese dioxide for 3 V lithium batteries SO JOURNAL OF POWER SOURCES LA English DT Article; Proceedings Paper CT 10th International Meeting on Lithium Batteries CY MAY 28-JUN 02, 2000 CL COMO, ITALY DE manganese dioxide; lithium batteries; hollandite ID ALPHA-MNO2 ELECTRODES AB Specific discharge capacities in excess of 200 mAh/g and good reversible cycling behavior between 3.8 and 2.0 V has been observed in a lithium cell for alpha -MnO2 phases with the hollandite structure. A combination of Lithia (Li2O) doping and ammonia (NH3) treatment of the active material powder having the composition alpha-[0.143Li(2)O .0.007NH(3)]. MnO2 gave the best electrochemical performance in liquid organic electrolyte (1:1 EC:DMC, 1 M LiPF6) coin cells, with metallic Li as the negative electrode. The added lithia forms a defect close-packed array of oxide anions and stabilizes the interior of the 2 x 2 tunnel of the hollandite structure by partially filling the crystallographic position (0,0,0.5) of the tetragonal unit cell (I4/m) with O2- from the added Li2O. Ammonia treatment is hypothesized to partially fill other lattice vacancies still available within the 2 x 2 tunnel with the nitrogen atoms from NH3 taking the same position as the oxide anion in the array. The NH3 can further stabilize the cell during lithium insertion/extraction because of its favorable hydrogen bonding ability and Lewis base characteristics. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Argonne Natl Lab, Div Chem Technol, Electrochem Technol Program, Argonne, IL 60439 USA. RP Johnson, CS (reprint author), Argonne Natl Lab, Div Chem Technol, Electrochem Technol Program, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 15 TC 24 Z9 25 U1 1 U2 28 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 JUL PY 2001 VL 97-8 SI SI BP 437 EP 442 DI 10.1016/S0378-7753(01)00686-3 PG 6 WC Chemistry, Physical; Electrochemistry; Energy & Fuels; Materials Science, Multidisciplinary SC Chemistry; Electrochemistry; Energy & Fuels; Materials Science GA 452AY UT WOS:000169836000103 ER PT J AU Lee, HS Yang, YQ Sun, X McBreen, J AF Lee, HS Yang, YQ Sun, X McBreen, J TI Synthesis of a new family of fluorinated boronate compounds as anion receptors and studies of their use as additives in lithium battery electrolytes SO JOURNAL OF POWER SOURCES LA English DT Article; Proceedings Paper CT 10th International Meeting on Lithium Batteries CY MAY 28-JUN 02, 2000 CL COMO, ITALY ID CONDUCTIVITY C1 Brookhaven Natl Lab, Upton, NY 11973 USA. RP Yang, YQ (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. NR 4 TC 26 Z9 29 U1 3 U2 13 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 JUL PY 2001 VL 97-8 SI SI BP 566 EP 569 DI 10.1016/S0378-7753(01)00535-3 PG 4 WC Chemistry, Physical; Electrochemistry; Energy & Fuels; Materials Science, Multidisciplinary SC Chemistry; Electrochemistry; Energy & Fuels; Materials Science GA 452AY UT WOS:000169836000135 ER PT J AU Amine, K Chen, CH Liu, J Hammond, M Jansen, A Dees, D Bloom, I Vissers, D Henriksen, G AF Amine, K Chen, CH Liu, J Hammond, M Jansen, A Dees, D Bloom, I Vissers, D Henriksen, G TI Factors responsible for impedance rise in high power lithium ion batteries SO JOURNAL OF POWER SOURCES LA English DT Article; Proceedings Paper CT 10th International Meeting on Lithium Batteries CY MAY 28-JUN 02, 2000 CL COMO, ITALY DE high power cell; ac-Impedance; charge-transfer resistance; reference electrode; symmetrical cell AB High-power, 18,650 lithium-ion cells have been designed and fabricated in order to understand the factors Limiting the calendar life of the Lithium-ion system. Each cell consisted of a LiNi0.8Co0.2O2 positive electrode, a blend of MCMB-6 and SFG-6 carbon negative electrode, and a LiPF6 in EC:DEC (1:1) electrolyte. These cells, which initially meet the power requirement set by the partnership for a new generation of vehicles (PNGV), were subjected to accelerated calendar life and cycle life testing. After testing at elevated temperatures, the cells experienced a significant impedance rise and loss of power. The fade rate of power in these cells was dependent of the state of charge and the temperature of testing. Micro-reference electrode and ac-impedance studies on symmetrical cells have confirmed that the interfacial resistance at the positive electrode was the main reason behind the impedance rise in the high power cell. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Argonne Natl Lab, Electrochem Technol Program, Argonne, IL 60439 USA. RP Amine, K (reprint author), Argonne Natl Lab, Electrochem Technol Program, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Chen, Chunhua/F-5897-2010; Amine, Khalil/K-9344-2013; Jansen, Andrew/Q-5912-2016 OI Jansen, Andrew/0000-0003-3244-7790 NR 8 TC 111 Z9 111 U1 4 U2 57 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 JUL PY 2001 VL 97-8 SI SI BP 684 EP 687 DI 10.1016/S0378-7753(01)00701-7 PG 4 WC Chemistry, Physical; Electrochemistry; Energy & Fuels; Materials Science, Multidisciplinary SC Chemistry; Electrochemistry; Energy & Fuels; Materials Science GA 452AY UT WOS:000169836000165 ER PT J AU Yeralan, S Pal, S Santoro, RJ AF Yeralan, S Pal, S Santoro, RJ TI Experimental study of major species and temperature profiles of liquid oxygen/gaseous hydrogen rocket combustion SO JOURNAL OF PROPULSION AND POWER LA English DT Article ID LASER RAMAN; DIAGNOSTICS AB Understanding the fundamentals of high-pressure, high-temperature combustion of practical rocket propellants is key to improving rocket engine performance and efficiency. The application of Raman spectroscopy for making detailed species concentration measurements of oxygen, hydrogen, and water vapor in the elevated-pressure, combusting flowfield downstream of a liquid-oxygen/gaseous-hydrogen swirl-coaxial injector element at fuel-rich conditions is presented. Details regarding measurement error analysis and recommendations fur further refinement of the diagnostic technique are also presented. To the authors' knowledge, these experiments represent the first time that instantaneous temperature and major species profiles have been successfully made in such an environment. These results, which include both instantaneous and time-averaged temperature and species concentration profiles, impact both rocket fuel preburner design and computational fluid dynamic code validation activities. C1 Penn State Univ, Prop Engn Res Ctr, University Pk, PA 16802 USA. Penn State Univ, Dept Engn Mech, University Pk, PA 16802 USA. RP Yeralan, S (reprint author), Sandia Natl Labs, MS 9051,POB 969, Livermore, CA 94551 USA. NR 22 TC 7 Z9 7 U1 0 U2 4 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 USA SN 0748-4658 J9 J PROPUL POWER JI J. Propul. Power PD JUL-AUG PY 2001 VL 17 IS 4 BP 788 EP 793 DI 10.2514/2.5834 PG 6 WC Engineering, Aerospace SC Engineering GA 454BN UT WOS:000169952700006 ER PT J AU Knoll, DA Rider, WJ Olson, GL AF Knoll, DA Rider, WJ Olson, GL TI Nonlinear convergence, accuracy, and time step control in nonequilibrium radiation diffusion SO JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER LA English DT Article DE radiation diffusion; nonlinear convergence; time step control ID SYSTEMS AB We study the interaction between converging the nonlinearities within a time step and time step control, on the accuracy of nonequilibrium radiation diffusion calculations. Typically, this type of calculation is performed using operator-splitting where the nonlinearities are lagged one time step. This method of integrating the nonlinear system results in an "effective" time-step constraint to obtain accuracy. A time-step control that limits the change in dependent variables (usually energy) per time step is used. We investigate the possibility that converging the nonlinearities within a time step may allow significantly larger time-step sizes and improved accuracy as well. The previously described Jacobian-free Newton-Krylov method (JQSRT 63 (1999) 15) is used to converge all nonlinearities within a time step. In addition, a new time-step control method, based on the hyperbolic model of a thermal wave (J. Comput. Phys. 152 (1999) 790), is employed. The benefits and cost of a second-order accurate time step are considered. It is demonstrated that for a chosen accuracy, significant increases in solution efficiency can be obtained by converging nonlinearities within a time step. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Appl Theoret & Computat Phys Div, Los Alamos, NM 87545 USA. RP Knoll, DA (reprint author), Univ Calif Los Alamos Natl Lab, Appl Theoret & Computat Phys Div, MS B216, Los Alamos, NM 87545 USA. NR 11 TC 37 Z9 40 U1 1 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0022-4073 J9 J QUANT SPECTROSC RA JI J. Quant. Spectrosc. Radiat. Transf. PD JUL 1 PY 2001 VL 70 IS 1 BP 25 EP 36 DI 10.1016/S0022-4073(00)00112-6 PG 12 WC Optics; Spectroscopy SC Optics; Spectroscopy GA 438GF UT WOS:000169044700003 ER PT J AU Miller, DS Graziani, F Rodrigue, G AF Miller, DS Graziani, F Rodrigue, G TI Benchmarks and models for time-dependent grey radiation transport with material temperature in binary stochastic media SO JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER LA English DT Article ID MIXTURES AB We present benchmark calculations for radiation transport coupled to a material temperature equation in a slab geometry binary random media. The mixing statistics are taken to be homogeneous Markov statistics where the material chunk sizes are described by Poisson distribution functions. The material opacities are taken to be constant, Benchmark values for time evolution of the ensemble average values of material temperature energy density and radiation transmission are computed via a Monte Carlo-type method. These benchmarks are used as a basis for comparison with three other approximate methods of solution. One of these approximate methods is simple atomic mix which is seen to consistently over absorb resulting in lower steady-state radiation transmission and material temperature, The second approximate model is an adaptation of what is commonly called the Levermore-Pomraning model and which we refer to as the standard model. It is shown to consistently under absorb resulting in higher steady-state radiation transmission and material temperature. We show that recasting the temperature coupling as a type of effective scattering can be useful in formulating the third approximate model, an adaptation of a model due to Su and Pomraning which attempts to account for the effects of scattering in a stochastic context, We show this last adaptation shows consistent improvement over both the atomic mix and standard models. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Univ Calif Davis, Dept Appl Sci, Davis, CA 95616 USA. RP Miller, DS (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808, Livermore, CA 94551 USA. NR 10 TC 13 Z9 13 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0022-4073 J9 J QUANT SPECTROSC RA JI J. Quant. Spectrosc. Radiat. Transf. PD JUL 1 PY 2001 VL 70 IS 1 BP 115 EP 128 DI 10.1016/S0022-4073(00)00128-X PG 14 WC Optics; Spectroscopy SC Optics; Spectroscopy GA 438GF UT WOS:000169044700010 ER PT J AU Henry, R Koller, D Liezers, M Farmer, OT Barinaga, C Koppenaal, DW Wacker, J AF Henry, R Koller, D Liezers, M Farmer, OT Barinaga, C Koppenaal, DW Wacker, J TI New advances in inductively coupled plasma - mass spectrometry (ICP-MS) for routine measurements in the nuclear industry SO JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY LA English DT Article; Proceedings Paper CT 5th International Conference on Methods and Applications of Radioanalytical Chemistry (MARC-V) CY APR 09-14, 2000 CL KAILUA-KONA, HAWAII SP Amer Nucl Soc Top AB Traditional methods of quantitation of radioactive isotopes include radioactivity counting and thermal ion mass spectrometry (TIMS). These techniques require extensive matrix separation and sample purification methods before unequivocal identification of specific isotopes and their relative abundance is possible. Counting techniques become very time consuming when the half-life of the target analyte is very long or the concentration of the analyte low. Atom counting using ICP-MS meets the nuclear industry requirements for many actinides and their daughter products. Recent improvements in quadrupole ICP-MS signal-to-background have resulted in attogram. mass detection capability and improved analysis of shorter half-life isotopes. C1 TJA Solut, Boulder, CO 80304 USA. TJA Solut, Winsford, Cheshire, England. Battelle PNNL, Richland, WA USA. RP Henry, R (reprint author), TJA Solut, 1812 Mapleton Ave, Boulder, CO 80304 USA. NR 1 TC 16 Z9 16 U1 0 U2 2 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0236-5731 J9 J RADIOANAL NUCL CH JI J. Radioanal. Nucl. Chem. PD JUL PY 2001 VL 249 IS 1 BP 103 EP 108 PG 6 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 465XZ UT WOS:000170616400017 ER PT J AU Inn, KGW McCurdy, D Bell, T Loesch, R Morton, JS Povinec, P Burns, K Henry, R Barss, NM AF Inn, KGW McCurdy, D Bell, T Loesch, R Morton, JS Povinec, P Burns, K Henry, R Barss, NM TI Standards, intercomparisons and performance evaluations for low-level and environmental radionuclide mass spectrometry and atom counting SO JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY LA English DT Article; Proceedings Paper CT 5th International Conference on Methods and Applications of Radioanalytical Chemistry (MARC-V) CY APR 09-14, 2000 CL KAILUA-KONA, HAWAII SP Amer Nucl Soc Top AB Because of the demand for higher sensitivity radionuclide measurements, atom counting technology will become an increasingly used modality in geo- and bio-studies, and process control operations. It is anticipated that requests for standards, intercomparisons and performance evaluations services will surge in the near future. In anticipation of such requests, the state-of-the-art needed to be assessed for proactive planning purposes. The results of a workshop focused on these issues indicated that there are several ongoing standards, intercomparisons and performance evaluations thrusts which are expected to expand in the future. Furthermore, new projects were planned and the Council on Ionizing Radiation Measurements and Standards (Public and Environmental Radiation Protection subcommittee) was proposed as an information coordinator. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Duke Engn & Serv, Bolton, MA USA. US DOE, Environm Hlth, Germantown, MD USA. US DOE, Environm Hlth, Idaho Falls, ID USA. Int Atom Energy Agcy, Monaco, Monaco. Int Atom Energy Agcy, Seibersdorf, Austria. TJA Solut, Boulder, CO USA. RP Inn, KGW (reprint author), Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. NR 4 TC 3 Z9 3 U1 0 U2 0 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0236-5731 J9 J RADIOANAL NUCL CH JI J. Radioanal. Nucl. Chem. PD JUL PY 2001 VL 249 IS 1 BP 109 EP 113 PG 5 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 465XZ UT WOS:000170616400018 ER PT J AU Lewis, D Miller, G Duffy, CJ Efurd, DW Inkret, WC Wagner, SE AF Lewis, D Miller, G Duffy, CJ Efurd, DW Inkret, WC Wagner, SE TI Los Alamos National Laboratory thermal ionization mass spectrometry results from intercomparison study of inductively coupled plasma mass spectrometry, thermal ionization mass spectrometry, and fission track analysis of mu Bq quantities of Pu-239 in synthetic urine (LA-UR-001698) SO JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY LA English DT Article; Proceedings Paper CT 5th International Conference on Methods and Applications of Radioanalytical Chemistry (MARC-V) CY APR 09-14, 2000 CL KAILUA-KONA, HAWAII SP Amer Nucl Soc Top AB In 1997, the Department of Energy, Office of International Health Programs (EH-63) contracted the National Institute of Standards and Technology (NIST) to perform an intercomparison to evaluate state-of-the-art analysis techniques for Pu-239 in synthetic urine in mu Bq quantities. Sample preparation was performed by Yankee Atomic Environmental Laboratory. Five replicate samples at spike amounts of 3.7, 9.26, 29.6, and 55.6 mu Bq and a blank amount were distributed to the participating laboratories in 200 g of synthetic urine. Los Alamos National Laboratory (LANL) participated in the intercomparison using thermal ionization mass spectrometry (TIMS). LANL results, system improvements, and future intercomparisons are discussed. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Lewis, D (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 9 TC 14 Z9 14 U1 0 U2 2 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0236-5731 J9 J RADIOANAL NUCL CH JI J. Radioanal. Nucl. Chem. PD JUL PY 2001 VL 249 IS 1 BP 115 EP 120 PG 6 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 465XZ UT WOS:000170616400019 ER PT J AU Inn, KGW McCurdy, D Kuruvilla, L Barss, NM Pietrzak, R Kaplan, E Inkret, W Efurd, W Rokop, D Lewis, D Gautier, P Bell, RT AF Inn, KGW McCurdy, D Kuruvilla, L Barss, NM Pietrzak, R Kaplan, E Inkret, W Efurd, W Rokop, D Lewis, D Gautier, P Bell, RT TI Intercomparison study of inductively coupled plasma mass spectrometry, thermal ionization mass spectrometry and fission track analysis of mu Bq quantities of Pu-239 in synthetic urine SO JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY LA English DT Article; Proceedings Paper CT 5th International Conference on Methods and Applications of Radioanalytical Chemistry (MARC-V) CY APR 09-14, 2000 CL KAILUA-KONA, HAWAII SP Amer Nucl Soc Top AB Even today, some Marshall Islanders are looking forward to permanently resettling their islands after five decades. The U.S. Department of Energy and the resettled residents require reasonable but cost-prudent assurance that the doses to residents from residual Pu-239 will not exceed recognized international standards or recommendations, as estimated from the excretion of Pu-239 in urine. The goal of this study was to evaluate the bias, uncertainty and sensitivity of analytical techniques that measure 3-56 mu Bq Pu-239 in synthetic urine. The analytical techniques studied in this work included inductively coupled plasma mass spectrometry, thermal ionization mass spectrometry and fission track analysis. The results of the intercomparison demonstrated that all three techniques were capable of making the measurements, although not with equal degree of bias and uncertainty. The estimated minimum detectable activity was 1 mu Bq of Pu-239 per synthetic urine sample. This exercise is also the first effort to certify test materials of plutonium in the nBq(.)g(-1) range. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Duke Engn & Serv, Bolton, MA USA. Int Hlth Program Off, US Dept Energy, Germantown, MD USA. Brookhaven Natl Lab, Upton, NY 11973 USA. Los Alamos Natl Lab, Los Alamos, NM USA. RP Inn, KGW (reprint author), Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. NR 6 TC 17 Z9 17 U1 0 U2 4 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0236-5731 J9 J RADIOANAL NUCL CH JI J. Radioanal. Nucl. Chem. PD JUL PY 2001 VL 249 IS 1 BP 121 EP 131 PG 11 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 465XZ UT WOS:000170616400020 ER PT J AU Frank, MI Prussin, SG Peterson, PF Tobin, MT AF Frank, MI Prussin, SG Peterson, PF Tobin, MT TI A Monte Carlo model of sea-level neutron background: Directionality, spectra, and intensity SO JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY LA English DT Article; Proceedings Paper CT 5th International Conference on Methods and Applications of Radioanalytical Chemistry (MARC-V) CY APR 09-14, 2000 CL KAILUA-KONA, HAWAII SP Amer Nucl Soc Top ID ATMOSPHERE; ENERGY AB We are developing a model of the cosmic my-induced neutron background at sea-level using the high-energy/Monte Carlo transport code MCNPX. The model accounts for and records anisotropy in neutron production from cosmic ray interactions, as well as the known "ground effect" neutron albedo. Initial results with an isothermal, constant density atmosphere in slab geometry show good agreement with experimental data on neutron intensity and low-energy directionality predicted previously. Our model also indicates significant net downward directionality above the energy range 0.1-1.0 MeV depending on the sea-level material composition. C1 Univ Calif Berkeley, Dept Nucl Engn, Berkeley, CA 94720 USA. Lawrence Livermore Natl Lab, Livermore, CA USA. RP Frank, MI (reprint author), Univ Calif Berkeley, Dept Nucl Engn, Berkeley, CA 94720 USA. NR 21 TC 6 Z9 6 U1 0 U2 0 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0236-5731 J9 J RADIOANAL NUCL CH JI J. Radioanal. Nucl. Chem. PD JUL PY 2001 VL 249 IS 1 BP 145 EP 151 PG 7 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 465XZ UT WOS:000170616400023 ER PT J AU DeVol, TA Egorov, OB Roane, JE Paulenova, A Grate, JW AF DeVol, TA Egorov, OB Roane, JE Paulenova, A Grate, JW TI Extractive scintillating resin for Tc-99 quantification in aqueous solutions SO JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY LA English DT Article; Proceedings Paper CT 5th International Conference on Methods and Applications of Radioanalytical Chemistry (MARC-V) CY APR 09-14, 2000 CL KAILUA-KONA, HAWAII SP Amer Nucl Soc Top ID SEPARATION; COLUMN AB A method utilizing extractive scintillating resin for Tc-99 monitoring in aqueous solutions is presented. These extractive scintillators combine analyte selective uptake and scintillating properties to produce dual functionality analytical resins. These resins were produced by (1) co-located extraction chromatographic resin and plastic scintillating beads, (2) immobilizing fluors in macroporous polystyrene supports to which chains of monomethylated polyethylene glycol have been grafted and (3) co-immobilizing organic scintillating fluors and a quaternary ammonium extractant (Aliquat-336) within macroporous acrylic and polystyrene supports. The first and third resins selectively extract pertechnetate ions from dilute acid whereas the second resin selectively extracts pertechnetate ions from high ionic strength solutions. These resins were utilized in similar to0.20 ml pore volume columns while 99Tc was continually monitored with commercially available scintillation detection systems. Manual and automated microfluidics were used to deliver sample and reagent solution for loading and elution of the 99Tc. The detection efficiencies were determined to be 45 and 70% for acrylic and polystyrene based resins, respectively, and independent of extractant. Minimum detectable 99Tc concentration using the Aliquat-336/acrylic-based resin was 6.2 Bq.l(-1) for a 50-ml sample and 30-minute count time. The new methodology was applied towards analysis of contaminated groundwater samples and nuclear waste simulants. C1 Clemson Univ, Dept Environm Engn & Sci, Clemson, SC 29634 USA. Pacific NW Natl Lab, Environm Mol Sci Lab, Walla Walla, WA 99362 USA. RP DeVol, TA (reprint author), Clemson Univ, Dept Environm Engn & Sci, Clemson, SC 29634 USA. NR 13 TC 22 Z9 22 U1 0 U2 7 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0236-5731 J9 J RADIOANAL NUCL CH JI J. Radioanal. Nucl. Chem. PD JUL PY 2001 VL 249 IS 1 BP 181 EP 189 PG 9 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 465XZ UT WOS:000170616400030 ER PT J AU Hinton, TG Knox, A Kaplan, D Serkiz, S AF Hinton, TG Knox, A Kaplan, D Serkiz, S TI An in situ method for remediating Cs-137-contaminated wetlands using naturally occurring minerals SO JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY LA English DT Article; Proceedings Paper CT 5th International Conference on Methods and Applications of Radioanalytical Chemistry (MARC-V) CY APR 09-14, 2000 CL KAILUA-KONA, HAWAII SP Amer Nucl Soc Top ID CS-137 AB Cesium's enhanced bioavailability in contaminated wetlands on the U.S. Department of Energy's Savannah River Site (SRS) is thought to be due to the low clay fraction of SRS soils, and that the clay mineralogy is dominated by kaolinites. Remediation of the wetlands is problematic because current technologies are destructive to the sensitive ecosystems. We tested I I clay minerals (two micas, a vermiculite, six illites, a kaolinite, and a smectite) for their propensity to sorb and retain Cs-137. Two minerals were subsequently chosen as candidates for in situ remediation amendment materials because they had 137Cs distribution coefficients (K-d) well in excess of 10,000 ml.g(-1), and desorbed less than 20% of the Cs when mixed in a 0.1 M NH4Cl solution. Incremental additions of the candidate minerals to Cs-137-contaminated sediments appreciably intercepted and retained desorbed Cs-137 in the presence of high levels of NH4. Implications for using the minerals as a nondestructive, in situ remediation technique are discussed. C1 Savannah River Ecol Lab, Aiken, SC 29802 USA. Westinghouse Savannah River Co, Aiken, SC USA. RP Hinton, TG (reprint author), Savannah River Ecol Lab, Drawer E, Aiken, SC 29802 USA. NR 10 TC 6 Z9 6 U1 4 U2 6 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0236-5731 J9 J RADIOANAL NUCL CH JI J. Radioanal. Nucl. Chem. PD JUL PY 2001 VL 249 IS 1 BP 197 EP 202 PG 6 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 465XZ UT WOS:000170616400032 ER PT J AU Drozhko, EG Glagolenko, YV Mokrov, YG Posokhov, AK Romanov, GN Volkanina, IL Stevenson, KA Hutter, AR AF Drozhko, EG Glagolenko, YV Mokrov, YG Posokhov, AK Romanov, GN Volkanina, IL Stevenson, KA Hutter, AR TI Radioactive contamination distribution in the bottom sediments and water of the Mishelyak River SO JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY LA English DT Article; Proceedings Paper CT 5th International Conference on Methods and Applications of Radioanalytical Chemistry (MARC-V) CY APR 09-14, 2000 CL KAILUA-KONA, HAWAII SP Amer Nucl Soc Top AB Joint Russian-American field studies have been conducted within the framework of a Memorandum of Cooperation between the Ministry of Atomic Energy for the Russian Federation and the U.S. Department of Energy and managed by the Joint Coordinating Committee on Environmental Restoration and Waste Management (JCCEM). We conducted the field studies discussed in this report in 1996 near the Mayak Production Association in the South Urals, Russia. The primary purpose of the research was to apply new methods to study the distribution of a containment plume originating from Lake Karachai an unlined radioactive waste repository, which is currently migrating into the Mishelyak River valley. This research was conducted within the frontal part of the contaminant water plume. The studies from this work include: surface water and soil moisture sampling with in situ radiometric measurements. The data from the radiometric measurements obtained in the field were then compared to laboratory measurements of field samples. Due to the possible inflow of the radionuclides from the groundwater to the Mishelyak River, this paper also describes the study of river bottom sediments and water contamination. C1 Minist Atom Energy Russian Federat, Mayak Prod Assoc, Ozyorsk, Russia. US DOE, Environm Measurements Lab, New York, NY 10014 USA. RP Drozhko, EG (reprint author), Minist Atom Energy Russian Federat, Mayak Prod Assoc, Ozyorsk, Russia. NR 4 TC 0 Z9 1 U1 0 U2 1 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0236-5731 J9 J RADIOANAL NUCL CH JI J. Radioanal. Nucl. Chem. PD JUL PY 2001 VL 249 IS 1 BP 203 EP 207 PG 5 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 465XZ UT WOS:000170616400033 ER PT J AU Hutter, A Wang, P Weeks, S AF Hutter, A Wang, P Weeks, S TI Innovative characterization, monitoring and sensor technologies for environmental radioactivity at USDOE sites SO JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY LA English DT Article; Proceedings Paper CT 5th International Conference on Methods and Applications of Radioanalytical Chemistry (MARC-V) CY APR 09-14, 2000 CL KAILUA-KONA, HAWAII SP Amer Nucl Soc Top AB The mission of the U. S. Department of Energy Office of Environmental Management EM) is to clean up its contaminated sites from the past production of nuclear weapons. Within EM, the Office of Science and Technology (OST) is responsible for providing a full range of science and technology resources needed to support resolution of EM cleanup and long-term environmental stewardship problems. This responsibility includes implementation of a technology development pathway from basic research to development, demonstration, and deployment of scientific and technological solutions needed by DOE sites. One OST Program is the Characterization, Monitoring, and Sensor Technology Crosscutting Program (CMST-CP), which aims to provide innovative technologies (i.e., faster, better, cheaper, and/or safer) for environmental characterization and monitoring. This paper describes several technologies that CMST-CP has supported for development with significant benefits realized or projected over the baseline characterization and monitoring practices. Examples of these technologies include mapping of subsurface radioactivity using Cone Penetrometer and drilling techniques; a Rapid Liquid Sampler for Sr, Ra, Tc, and Cs using 3M Empore (TM) Rad Disks; Long-Range Alpha Detectors; a Compact High Resolution Spectrometer;, BetaScint (TM) for determination of Sr in soil; Laser-Induced Fluorescence Imaging techniques for mapping U on surfaces; the Environmental Measurements While Drilling System; and the Expedited Site Characterization methodology. C1 US DOE, Environm Measurements Lab, New York, NY 10014 USA. Concurrent Technol Corp, Pittsburgh, PA 15238 USA. Special Technol Lab, Santa Barbara, CA 93111 USA. RP Hutter, A (reprint author), US DOE, Environm Measurements Lab, New York, NY 10014 USA. NR 11 TC 1 Z9 1 U1 1 U2 2 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0236-5731 J9 J RADIOANAL NUCL CH JI J. Radioanal. Nucl. Chem. PD JUL PY 2001 VL 249 IS 1 BP 209 EP 214 PG 6 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 465XZ UT WOS:000170616400034 ER PT J AU Schwarz, JP Liu, RM Newell, DB Steiner, RL Williams, ER Smith, D Erdemir, A Woodford, J AF Schwarz, JP Liu, RM Newell, DB Steiner, RL Williams, ER Smith, D Erdemir, A Woodford, J TI Hysteresis and related error mechanisms in the NIST watt balance experiment SO JOURNAL OF RESEARCH OF THE NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY LA English DT Article DE DLC coating; hysteresis; Josephson constant; kilogram artifact; Planck constant; watt balance AB The NIST watt balance experiment is being completely rebuilt after its 1998 determination of the Planck constant. That measurement yielded a result with an approximately 1 x 10(-7) relative standard uncertainty. Because the goal of the new incarnation of the experiment is a ten-fold decrease in uncertainty, it has been necessary to reexamine many sources of systematic error. Hysteresis effects account for a substantial portion of the projected uncertainty budget. They arise from mechanical, magnetic, and thermal sources. The new experiment incorporates several improvements in the apparatus to address these issues, including stiffer components for transferring the mass standard on and off the balance, better servo control of the balance, better pivot materials, and the incorporation of erasing techniques into the mass transfer servo system. We have carried out a series of tests of hysteresis sources on a separate system, and apply their results to the watt apparatus. The studies presented here suggest that our improvements can be expected to reduce hysteresis signals by at least a factor of 10-perhaps as much as a factor of 50-over the 1998 experiment. C1 NIST, Gaithersburg, MD 20899 USA. Argonne Natl Lab, Argonne, IL 60439 USA. RP Schwarz, JP (reprint author), NIST, Gaithersburg, MD 20899 USA. EM joshua.schwarz@nist.gov; ruimin.liu@nist.gov; david.newell@nist.gov; richard.steiner@nist.gov; edwin.williams@nist.gov; douglas.smith@nist.gov RI schwarz, joshua/G-4556-2013 OI schwarz, joshua/0000-0002-9123-2223 NR 14 TC 15 Z9 15 U1 0 U2 8 PU US GOVERNMENT PRINTING OFFICE PI WASHINGTON PA SUPERINTENDENT DOCUMENTS,, WASHINGTON, DC 20402-9325 USA SN 1044-677X J9 J RES NATL INST STAN JI J. Res. Natl. Inst. Stand. Technol. PD JUL-AUG PY 2001 VL 106 IS 4 BP 627 EP 640 DI 10.6028/jres.106.028 PG 14 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 475KL UT WOS:000171163100001 PM 27500039 ER PT J AU Fomel, S Vaillant, L AF Fomel, S Vaillant, L TI Evaluating the Stolt-stretch parameter SO JOURNAL OF SEISMIC EXPLORATION LA English DT Article DE Stolt-stretch; migration; algorithm; traveltime; W parameter; North Sea ID MIGRATION; MEDIA AB The Stolt migration extension to a variable velocity case describes the velocity heterogeneity with a constant parameter, which is related to the stretch transformation of the time axis. We exploit a connection between modified dispersion relations and nonhyperbolic traveltime approximations to derive an explicit expression for the stretch parameter. This analytical expression allows one to achieve the highest possible accuracy within the Stolt-stretch approximation. Using a real data example, we demonstrate an application of the explicit Stolt-stretch formula for an optimal partitioning of the migration velocity in the method of cascaded migrations. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. UNILOG, DO SCL, F-75008 Paris, France. 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 22 TC 2 Z9 2 U1 0 U2 2 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 JUL PY 2001 VL 9 IS 4 BP 319 EP 335 PG 17 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 463QV UT WOS:000170489500004 ER PT J AU Kunerth, DC Weinberg, DM Rector, JW Scott, CL Johnson, JT AF Kunerth, DC Weinberg, DM Rector, JW Scott, CL Johnson, JT TI Acoustic laboratory measurements during the formation of a THF-hydrate in unconsolidated porous media SO JOURNAL OF SEISMIC EXPLORATION LA English DT Article DE hydrates; ultrasonic investigation; seismic response; laboratory measurements; acoustics; porous media ID METHANE HYDRATE; GAS; SEDIMENTS; RESOURCES AB Compressional and shear wave experiments are performed for a tetrahydrofuran (THF) hydrate/sand mixture. The THF cell allows for simultaneous measurement of the temperature gradient as well as reflected compressional (P) and shear (S) wave velocities as a function of time and temperature. Results from these early experiments illustrate the evolution of a multiphase system where THF hydrates form in pore bodies and only affect the bulk properties of the sediment. As temperature is decreased, remaining fluid water in the pores freezes and welds the grains affecting the shear strength of the sediment. C1 Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. Univ Calif Berkeley, Dept Mat Sci & Mineral Engn, Berkeley, CA 94720 USA. RP Kunerth, DC (reprint author), Idaho Natl Engn & Environm Lab, POB 1625, Idaho Falls, ID 83415 USA. RI Johnson, James/B-9689-2017 OI Johnson, James/0000-0002-3434-4413 NR 22 TC 10 Z9 10 U1 1 U2 5 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 JUL PY 2001 VL 9 IS 4 BP 337 EP 354 PG 18 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 463QV UT WOS:000170489500005 ER PT J AU Melik-Alaverdian, V Ortiz, G Bonesteel, NE AF Melik-Alaverdian, V Ortiz, G Bonesteel, NE TI Quantum projector method on curved manifolds SO JOURNAL OF STATISTICAL PHYSICS LA English DT Article DE stochastic or statistical methods; quantum Monte Carlo; fermion methods; generalized diffusion equation; quantum hell physics ID MONTE-CARLO; MODEL AB A generalized stochastic method for projecting out the ground state of the quantum many-body Schrodinger equation on curved manifolds is introduced. This random-walk method is of wide applicability to any second order differential equation (first order in time), in any spatial dimension. The technique reduces to determining the proper "quantum corrections" for the Euclidean short-time propagator that is used to build up their path-integral Monte Carlo solutions. For particles with Fermi statistics the "Fixed-Phase" constraint (which amounts to fixing the phase of the many-body state) allows one to obtain stable, albeit approximate, solutions with a variational property. We illustrate the method by applying it to the problem of an electron moving on the surface of a sphere in the presence of a Dirac magnetic monopole. C1 Univ Rhode Isl, Dept Phys, Kingston, RI 02881 USA. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Florida State Univ, Natl High Magnet Field Lab, Tallahassee, FL 32306 USA. Florida State Univ, Dept Phys, Tallahassee, FL 32306 USA. RP Melik-Alaverdian, V (reprint author), Univ Rhode Isl, Dept Phys, Kingston, RI 02881 USA. NR 20 TC 1 Z9 1 U1 1 U2 3 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0022-4715 J9 J STAT PHYS JI J. Stat. Phys. PD JUL PY 2001 VL 104 IS 1-2 BP 449 EP 470 DI 10.1023/A:1010326231389 PG 22 WC Physics, Mathematical SC Physics GA 463VT UT WOS:000170498500015 ER PT J AU Peterson, C Simon, M Hodges, J Mertens, P Higgins, L Egelman, E Anderson, D AF Peterson, C Simon, M Hodges, J Mertens, P Higgins, L Egelman, E Anderson, D TI Composition and mass of the bacteriophage phi 29 prohead and virion SO JOURNAL OF STRUCTURAL BIOLOGY LA English DT Article DE bacteriophage phi 29 structure; phi 29 composition; phi 29 mass ID HEAD-TAIL CONNECTOR; BACILLUS-SUBTILIS; 5' TERMINI; 13-FOLD SYMMETRY; IN-VITRO; DNA; PROTEIN; GENOME; RNA; RESOLUTION AB The protein composition of the Bacillus subtilis bacteriophage phi 29 prohead and virion was determined by combustion of gel bands of H-3-labeled proteins. Copy numbers of individual proteins were calculated relative to the 12 copies of the head-tail connector protein. The mean numbers of copies of the major capsid protein in the prohead and virion were 241 and 218, respectively, approaching the 235 copies determined previously by cryoelectron. microscopy. The mean numbers of copies of the dimeric head fiber on the prohead and virion were 24 and 31, respectively, demonstrating partial occupancy of the 55 fiber binding sites. Measured copies of neck and tail proteins in the virion included I I of the lower collar, 58 of the appendage, and 9 of the tail; if the true copies of these proteins are 12, 60, and 9, respectively, the entire neck and tail of phi 29 has quasi-sixfold symmetry. The mass of the fiberless prohead with pRNA was about 14.2 MDa, and the mass of the prohead determined by scanning transmission electron microscopy was consistent with the biochemical data. The mass of the fiberless virion containing the 12.8-MDa DNA genome was about 30.4 MDa. A full complement of dimeric fibers on the prohead or virion would increase the mass of the particle by about 3.2 MDa. The data complement studies relating the structure of phi 29 components to dynamic functions in morphogenesis and infection. (C) 2001 Academic Press. C1 Univ Minnesota, Dept Oral Sci, Minneapolis, MN 55455 USA. Univ Minnesota, Dept Microbiol, Minneapolis, MN 55455 USA. Univ Minnesota, Dept Biochem, Minneapolis, MN 55455 USA. Univ Minnesota, Div Biostat, Minneapolis, MN 55455 USA. Brookhaven Natl Lab, Dept Biol, Upton, NY 11973 USA. Packard BioSci BV, Groningen, Netherlands. Univ Virginia, Hlth Sci Ctr, Dept Biochem, Charlottesville, VA 22908 USA. RP Anderson, D (reprint author), Univ Minnesota, Dept Oral Sci, 18-242 Moos Tower,515 Deleware St SE, Minneapolis, MN 55455 USA. RI Egelman, Edward/A-2488-2009; OI Egelman, Edward/0000-0003-4844-5212 FU NCRR NIH HHS [P41-RR01777]; NIDCR NIH HHS [P30-DE09737] NR 34 TC 17 Z9 23 U1 0 U2 1 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 1047-8477 J9 J STRUCT BIOL JI J. Struct. Biol. PD JUL PY 2001 VL 135 IS 1 BP 18 EP 25 DI 10.1006/jsbi.2001.4375 PG 8 WC Biochemistry & Molecular Biology; Biophysics; Cell Biology SC Biochemistry & Molecular Biology; Biophysics; Cell Biology GA 480DU UT WOS:000171447400003 PM 11562162 ER PT J AU Toellner, TS Hu, MY Sturhahn, W Bortel, G Alp, EE Zhao, J AF Toellner, TS Hu, MY Sturhahn, W Bortel, G Alp, EE Zhao, J TI Crystal monochromator with a resolution beyond 10(8) SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article DE X-ray optics; crystal monochromators; nuclear resonant scattering; phonons; SnO ID NUCLEAR RESONANT SCATTERING; MEV ENERGY RESOLUTION; SYNCHROTRON-RADIATION; INELASTIC-SCATTERING; SN-119 AB Monochromatization with crystal diffraction has been achieved to a resolution (lambda/Delta lambda) beyond 10(8). The monchromator is specifically designed for 23.880 keV synchrotron radiation (lambda = 51.9 pm) for applications involving nuclear resonant scattering from Sn-119. The design uses asymmetrically cut silicon (12 12 12) crystal reflections from two single-crystalline monoliths oriented in a dispersive geometry. A transmitted energy bandwidth of 140 +/- 20 mu eV was measured, corresponding to a resolution of 1.7 +/- 10(8). Methods of improving efficiency, wavelength stability and resolution are discussed. C1 Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. RP Toellner, TS (reprint author), Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. NR 19 TC 16 Z9 16 U1 0 U2 3 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0909-0495 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD JUL PY 2001 VL 8 BP 1082 EP 1086 DI 10.1107/S0909049501007257 PN 4 PG 5 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 446WP UT WOS:000169537400003 PM 11486359 ER PT J AU Winebrake, JJ Wang, MQ He, DQ AF Winebrake, JJ Wang, MQ He, DQ TI Toxic emissions from mobile sources: A total fuel-cycle analysis for conventional and alternative fuel vehicles SO JOURNAL OF THE AIR & WASTE MANAGEMENT ASSOCIATION LA English DT Article AB Mobile sources are among the largest contributors of four hazardous air pollutants-benzene, 1,3-butadiene, acetaldehyde, and formaldehyde-in urban areas. At the same time, federal and state governments are promoting the use of alternative fuel vehicles as a means to curb local air pollution. As yet, the impact of this movement toward alternative fuels with respect to toxic emissions has not been well studied. The purpose of this paper is to compare toxic emissions from vehicles operating on a variety of fuels, including reformulated gasoline (RFG), natural gas, ethanol, methanol, liquid petroleum gas (LPG), and electricity. This study uses a version of Argonne National Laboratory's Greenhouse Gas, Regulated Emissions, and Energy Use in Transportation (GREET) model, appropriately modified to estimate toxic emissions. The GREET model conducts a total fuel-cycle analysis that calculates emissions from both downstream (e.g., operation of the vehicle) and upstream (e.g., fuel production and distribution) stages of the fuel cycle. We find that;almost all of the fuels studied reduce 1,3-butadiene emissions compared with conventional gasoline (CG). However, the use of ethanol in E85 (fuel made with 85% ethanol) or RFG leads to increased acetaldehyde emissions, and the use of methanol, ethanol, and compressed natural gas (CNG) may result in increased formaldehyde emissions. When the modeling results for the four air toxics are considered together with their cancer risk factors, all the fuels and vehicle technologies show air toxic emission reduction benefits. C1 James Madison Univ, Integrated Sci & Technol Dept, Harrisonburg, VA 22807 USA. Argonne Natl Lab, Ctr Transportat Res, Argonne, IL 60439 USA. RP Winebrake, JJ (reprint author), James Madison Univ, Integrated Sci & Technol Dept, Harrisonburg, VA 22807 USA. RI Winebrake, James/D-2478-2010 NR 38 TC 33 Z9 34 U1 0 U2 6 PU AIR & WASTE MANAGEMENT ASSOC PI PITTSBURGH PA ONE GATEWAY CENTER, THIRD FL, PITTSBURGH, PA 15222 USA SN 1047-3289 J9 J AIR WASTE MANAGE JI J. Air Waste Manage. Assoc. PD JUL PY 2001 VL 51 IS 7 BP 1073 EP 1086 PG 14 WC Engineering, Environmental; Environmental Sciences; Meteorology & Atmospheric Sciences SC Engineering; Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA 451YA UT WOS:000169829300012 PM 15658225 ER PT J AU Schelling, PK Phillpot, SR Wolf, D AF Schelling, PK Phillpot, SR Wolf, D TI Mechanism of the cubic-to-tetragonal phase transition in zirconia and yttria-stabilized zirconia by molecular-dynamics simulation SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID DEFECT STRUCTURE; SOFT MODE; ZRO2; ENERGETICS; POLYMORPHS; POTENTIALS; ZRO2-Y2O3; DESCRIBE; SYSTEMS; OXIDES AB We present a new interatomic potential capable of describing the cubic and tetragonal phases of zirconia. From an analysis of molecular-dynamics simulations of the structural fluctuations in the cubic phase close to the transition temperature, we show that the cubic-to-tetragonal transition is displacive. In addition, the discontinuous change in volume and the latent heat at the transition demonstrate clearly that the transition is first order. The model correctly predicts that doping with yttria tends to stabilize the cubic phase at lower temperatures. A description of the first-order nature of dopant-driven transitions is given. 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 41 TC 75 Z9 77 U1 1 U2 25 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43081-6136 USA SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD JUL PY 2001 VL 84 IS 7 BP 1609 EP 1619 PG 11 WC Materials Science, Ceramics SC Materials Science GA 452FZ UT WOS:000169848300035 ER PT J AU de Arellano-Lopez, AR Melendez-Martinez, JJ Dominguez-Rodriguez, A Routbort, JL Lin, HT Becher, PF AF de Arellano-Lopez, AR Melendez-Martinez, JJ Dominguez-Rodriguez, A Routbort, JL Lin, HT Becher, PF TI Grain-size effect on compressive creep of silicon-carbide-whisker-reinforced aluminum oxide SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID MECHANISMS; AL2O3; DEFORMATION AB The steady-state compressive creep of Al2O3 with 10 vol% SiC whiskers having grain sizes of 1.2, 2.3, and 4.0 mum has been measured at 1400 degreesC in argon. The creep rate is related to the free volume within the whisker network, not the nominal grain size. The results are consistent with diffusional-controlled creep with different contributions from grain-boundary sliding. Under low stresses, only Liftshitz sliding is possible and the diffusional process controls deformation, while at stresses over a threshold, Rachinger sliding is the mechanism controlling deformation. The evolution between Liftshitz and Rachinger sliding is marked by a significant increase in the value of the stress exponent. C1 Univ Sevilla, Dept Fis Mat Condensada, Seville, Spain. Argonne Natl Lab, Div Energy Technol, Argonne, IL 60439 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP de Arellano-Lopez, AR (reprint author), Univ Sevilla, Dept Fis Mat Condensada, Seville, Spain. RI Melendez, Juan Jose/A-6524-2013; OI Melendez, Juan Jose/0000-0003-1036-6666; R. de Arellano Lopez, Antonio/0000-0002-7443-0244; Dominguez-Rodriguez, Arturo/0000-0003-1598-5669 NR 10 TC 2 Z9 2 U1 0 U2 2 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43081-6136 USA SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD JUL PY 2001 VL 84 IS 7 BP 1645 EP 1647 PG 3 WC Materials Science, Ceramics SC Materials Science GA 452FZ UT WOS:000169848300042 ER PT J AU Van Berkel, GJ Asano, KG Schnier, PD AF Van Berkel, GJ Asano, KG Schnier, PD TI Electrochemical processes in a wire-in-a-capillary bulk-loaded, nano-electrospray emitter SO JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY LA English DT Article ID IONIZATION MASS-SPECTROMETRY; CURRENT ELECTROLYTIC PROCESS; GAS-PHASE; AMINO-ACIDS; ION-SOURCE; COMPLEXES; MS; MECHANISM; INTERFACE; INHERENT AB Experiments are described that illustrate solvent oxidation, emitter electrode corrosion, and analyte oxidation in positive ion mode nano-electrospray mass spectrometry using a wire-ina-capillary, bulk-loaded nano-electrospray emitter geometry. Time-lapsed color photography of pH and metal specific indicator solutions within operating nano-electrospray emitters, as well as temporal changes in the ions observed in the nano-electrospray mass spectra, are used to probe these reactions, judge their magnitude, and study the time dependent changes in solution composition and gas-phase ion signal brought about as a result of these electrochemical reactions. The significance of these observations for analytical applications of nanoelectrospray mass spectrometry are discussed. Published by Elsevier Science Inc. C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Organ & Biol Mass Spectrometry Grp, Oak Ridge, TN 37831 USA. RP Van Berkel, GJ (reprint author), Oak Ridge Natl Lab, Div Chem & Analyt Sci, Organ & Biol Mass Spectrometry Grp, POB 2008, Oak Ridge, TN 37831 USA. RI Asano, Keiji/L-3164-2016 OI Asano, Keiji/0000-0003-2254-3586 NR 38 TC 92 Z9 92 U1 1 U2 19 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 JUL PY 2001 VL 12 IS 7 BP 853 EP 862 PG 10 WC Chemistry, Analytical; Chemistry, Physical; Spectroscopy SC Chemistry; Spectroscopy GA 447HH UT WOS:000169565500013 PM 11444609 ER PT J AU Giorgetti, M Mukerjee, S Passerini, S McBreen, J Smyrl, WH AF Giorgetti, M Mukerjee, S Passerini, S McBreen, J Smyrl, WH TI Evidence for reversible formation of metallic Cu in Cu0.1V2O5 xerogel cathodes during intercalation cycling of Li+ ions as detected by X-ray absorption spectroscopy SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID BODY DISTRIBUTION-FUNCTIONS; V2O5 XEROGEL; LITHIUM INTERCALATION; CONDENSED MATTER; VANADIUM-OXIDES; FINE-STRUCTURE; AEROGELS; COPPER; EDGE; BATTERIES AB Vanadium pentoxide materials prepared through sol-gel processes (xerogel. aerogel. and aerogel-like) act as excellent intercalation hosts for lithium as well as polyvalent cations. The large lithium insertion capacity of these materials makes them attractive for use as cathodes in high-capacity lithium batteries. Copper-doped V2O5-based cathodes have excellent properties in terms of high intercalation rate and very good reversibility upon cycling with no capacity hiding after more than 450 cycles. This paper reports in situ X-ray absorption spectroscopy (XAS) investigations of copper-doped V2O5 xerogel. The K-edge X-ray adsorption thresholds of V and Cu were studied. The local structure around copper is found to change dramatically during individual insertion/ release cycles for Li+ ions. The XAS analysis indicates that the lithiation of the Cu0.1V2O5 xerogel cathode proceeds with concurrent formation of copper metal. However. the starting compound is regenerated upon releasing the inserted lithium (charging the cathode), thus revealing the foundation for excellent structural and electronic reversibility of the material. (C) 2001 The Electrochemical Society. C1 Univ Minnesota, Dept Chem Engn & Mat Sci, Corros Res Ctr, Minneapolis, MN 55455 USA. Northeastern Univ, Dept Chem, Boston, MA 02115 USA. ENEA, CR Casaccia, I-00060 Rome, Italy. Brookhaven Natl Lab, Div Mat Sci, Dept Appl Sci, Upton, NY 11973 USA. RP Giorgetti, M (reprint author), Univ Bologna, Dept Phys & Inorgan Chem, I-40136 Bologna, Italy. RI Passerini, Stefano/A-3859-2015; OI Passerini, Stefano/0000-0002-6606-5304; Giorgetti, Marco/0000-0001-7967-8364 NR 42 TC 37 Z9 37 U1 2 U2 17 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 JUL PY 2001 VL 148 IS 7 BP A768 EP A774 DI 10.1149/1.1379029 PG 7 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA 453BR UT WOS:000169897300018 ER PT J AU Matsuo, Y Kostecki, R McLarnon, F AF Matsuo, Y Kostecki, R McLarnon, F TI Surface layer formation on thin-film LiMn2O4 electrodes at elevated temperatures SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID LI/LIXMN2O4 RECHARGEABLE CELLS; MANGANESE OXIDE SPINEL; CAPACITY LOSSES; LI/LIMN2O4 CELLS; ION BATTERIES; DISSOLUTION; PERFORMANCE; INSERTION AB Thin-film LiMn2O4 electrodes, which were exposed to pure dimethyl carbonate (DMC) or to a mixture of ethylene carbonate (EC) and DMC (1:1 by volume) containing 1 M LiPF6 at elevated temperatures, were studied by using X-ray diffraction, current-sensing atomic force microscopy (CSAFM), cyclic voltammetry. ordinary Raman spectroscopy, and surface-enhanced Raman spectroscopy (SERS). Thin, electronically insulating surface layers were detected by CSAFM and SERS on all electrodes. The surface layer formed by exposure to DMC at 70 degreesC was uniform and preserved the electrode structure, however, it led to complete electrode deactivation, probably due to loss of surface electronic conductivity and slower lithium-ion transport rates through the surface layer. A similar surface layer was formed when the electrodes were exposed to EC-DMC-LiPF6, however. the layer formed at 70 degreesC did not prevent LiMn2O4 decomposition and consequent electrode capacity loss. In this case, manganese dissolution was observed, accompanied by the formation of lambda -MnO2. SER spectra of the surface layers suggest that they were formed as a result of DMC decomposition at the LiMn2O4 surface. The SER spectra displayed bands characteristic of Li-O-R, carbonate, and carboxyl groups. Derivatives of carbon-oxygen triple bonds or silver-carbon-oxygen groups. which are possibly a result of interactions between the surface layer and silver microparticles. were also detected. (C) 2001 The Electrochemical Society. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Environm Energy Technol Div, Berkeley, CA 94720 USA. RP Matsuo, Y (reprint author), Himeji Inst Technol, Himeji, Hyogo 6712201, Japan. NR 24 TC 99 Z9 100 U1 3 U2 59 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 JUL PY 2001 VL 148 IS 7 BP A687 EP A692 DI 10.1149/1.1373658 PG 6 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA 453BR UT WOS:000169897300004 ER PT J AU Xia, YY Sakai, T Fujieda, T Yang, XQ Sun, X Ma, ZF McBreen, J Yoshio, M AF Xia, YY Sakai, T Fujieda, T Yang, XQ Sun, X Ma, ZF McBreen, J Yoshio, M TI Correlating capacity fading and structural changes in Li1+yMn2-yO4-delta spinel cathode materials - A systematic study on the effects of Li/Mn ratio and oxygen deficiency SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID RECHARGEABLE LITHIUM BATTERIES; X-RAY-DIFFRACTION; PHASE-TRANSITION; LI/LIMN2O4 CELLS; ION BATTERIES; LIMN2O4; INSERTION AB Several series of Li1+/-yMn2O4+/-delta samples with the spinel structure were synthesized. These samples had different Li/Mn ratios (by varying the Li/Mn ratio used in stirling materials) and various oxygen contents (by controlling synthesis conditions, including temperature, heat-treatment time, and purging gas during both the solid-state reaction and annealing). In systematic studies of charge-discharge cycling behavior and in situ X-ray diffraction (XRD) at room temperature, it was found that both the charge/ discharge profile and the structural changes during cycling are closely related to the degree of oxygen deficiency created in the synthesis process. Their effects on the capacity fading are much more important than the Li/Mn ratio or other factors. A higher degree of oxygen deficiency is accompanied with a faster fading of capacity during cycling. In cells using spinel cathodes with an oxygen deficiency. the capacity fading during cycling occurs on both the 4.2 and 4.0 V plateaus. This behavior is quite different from that found in cathodes without an oxygen deficiency, where most of the capacity fading occurs on the 4.7 V plateau region only. Our in situ XRD results indicate clearly that the capacity fading on the 4.2 V plateau is related to the phase transition between the cubic II and cubic III (lambda -MnO2) structure, while the capacity fading on the 4.0 V plateau is related to the phase transition between the cubic I and cubic II spinel structures. The effects of oxygen deficiency on the structural phase transition of Li1+/-yMn2O4+/-delta-type materials at temperatures around 10 degreesC were also studied. It was found that this phase transition is closely related to the degree of oxygen deficiency of the material. In samples with no oxygen deficiency, this phase transition disappeared. (C) 2001 The Electrochemical Society. C1 Osaka Natl Res Inst, Battery Sect, Osaka 5638577, Japan. Brookhaven Natl Lab, Upton, NY 11973 USA. Saga Univ, Dept Appl Chem, Saga 8408502, Japan. RP Xia, YY (reprint author), Osaka Natl Res Inst, Battery Sect, Osaka 5638577, Japan. NR 22 TC 124 Z9 129 U1 10 U2 66 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 JUL PY 2001 VL 148 IS 7 BP A723 EP A729 DI 10.1149/1.1376117 PG 7 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA 453BR UT WOS:000169897300011 ER PT J AU Son, KA Missert, N Barbour, JC Hren, JJ Copeland, RG Minor, KG AF Son, KA Missert, N Barbour, JC Hren, JJ Copeland, RG Minor, KG TI Growth and oxidation of thin film Al2Cu SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID AL-CU; INTERMETALLIC PHASES; LOCALIZED CORROSION; ALLOYS; ALUMINUM; COPPER AB Al2Cu thin films (similar to 382 nm) are fabricated by melting and resolidifying Al/Cu bilayers on a SiO2 on Si(100) substrate in the presence of a similar to3 nm Al2O3 passivating layer. X-ray photoelectron spectroscopy (XPS) measures a 1.0 eV shift of the Cu 2p(3/2) peak and a 1.6 eV shift of the valance band relative to metallic Cu upon Al2Cu formation. Scanning electron microscopy and electron back-scattered diffraction show that the Al2Cu film is composed of 30-70 mum wide and 10-15 mm long cellular grains with (110) orientation. The atomic composition of the film as estimated by energy dispersive spectroscopy is 67 +/- 2% Al and 33 +/- 2% Cu. XPS scans of Al2O3/Al2Cu taken before and after air exposure indicate that the upper Al2Cu layers undergo further oxidation to Al2O3 even in the presence of similar to5 nm Al2O3. The majority of Cu produced from oxidation is believed to be excluded from the Al2O3 layers, based upon the lack of evidence for metallic Cu in the XPS scans. In contrast to Al/Cu passivated with Al2O3. melting/resolidifying the Al/Cu bilayer without Al2O3 results in phase-segregated dendritic film growth. (C) 2001 The Electrochemical Society. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. N Carolina State Univ, Raleigh, NC 27695 USA. RP Son, KA (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 16 TC 3 Z9 3 U1 2 U2 14 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 JUL PY 2001 VL 148 IS 7 BP B260 EP B263 DI 10.1149/1.1376635 PG 4 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA 453BR UT WOS:000169897300024 ER PT J AU Treimer, SE Feng, JR Johnson, DC AF Treimer, SE Feng, JR Johnson, DC TI Photoassisted electrochemical incineration of selected organic compounds SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID WASTE-WATER TREATMENT; OXYGEN-TRANSFER REACTIONS; HIGH OVERVOLTAGE ANODES; PHOTOCATALYTIC DEGRADATION; TITANIUM-DIOXIDE; ASSISTED PHOTOCATALYSIS; SNO2 ANODES; 4-CHLOROPHENOL; OXIDATION; ELECTROCATALYSIS AB The decrease in chemical oxygen demand (COD) of mildly acidic (pH 3.5) aqueous solutions of phenol, aniline, n-propanol, and acetic acid was observed to be significantly larger at PbO2(s)-coated Pt electrodes ("PbO2/Pt") in comparison to bare Pt electrodes in a flow-through reactor. Furthermore, the rate of CO2(g) production during electrolysis of phenol solutions at PbO2/Pt electrodes (4.6 cm(2)) also was determined to be significantly larger when these electrode surfaces were illuminated by a 14 W UV lamp (254 nm). The total amount of CO2(g) produced over a 4 h electrolysis period at an illuminated PbO2/Pt electrode in a Bow-through cell was equal to 90% of the theoretical amount, corresponding to stoichiometric conversion of the phenol to CO2(g). Elemental analysis of the PbO2(s) films demonstrated that they were doped slightly with iron, presumably in the Fe(III) state, i.e., Fe(III)/Pb(IV) = 0.010. Thr sourer of Fe(III) was concluded to be the stainless steel used in construction of the flow-through electrolysis vessel. It is speculated that the Fe(III) sites in the surfaces of the PbO2(s) films can function as Lewis acid sites for adsorption of reactant molecules via nonbonded electrons as an initial step in the anodic degradation mechanisms. The advantage of preadsorption of reactant molecules is thought to be the result of longer residence times for these molecules within the applied electric field at the electrode-solution interfacial region. The observed effect of UV illumination is speculated to be associated with absorption of the photons within the surface of the PbO2(s) films. (C) 2001 The Electrochemical Society. C1 Iowa State Univ Sci & Technol, Dept Chem, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Ames Lab, US DOE, Ames, IA 50011 USA. RP Treimer, SE (reprint author), Iowa State Univ Sci & Technol, Dept Chem, Ames, IA 50011 USA. NR 43 TC 12 Z9 13 U1 0 U2 2 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 JUL PY 2001 VL 148 IS 7 BP E321 EP E325 DI 10.1149/1.1378292 PG 5 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA 453BR UT WOS:000169897300047 ER PT J AU Paparazzo, E Lea, AS Baer, DR Northover, JP AF Paparazzo, E Lea, AS Baer, DR Northover, JP TI Scanning Auger microscopy studies of an ancient bronze SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A LA English DT Article; Proceedings Paper CT 47th International Symposium of AVS CY OCT 02-06, 2000 CL BOSTON, MA SP AVS ID RAY PHOTOELECTRON-SPECTROSCOPY; ENERGY; OXIDATION; ALLOYS AB Scanning Auger microscopy (SAM) has been used to study the surface and interface microchemistry of a sheet bronze belt from the Urartian kingdom in NE Syria of the early first millennium B.C. We find that the patina contains no copper species at all (decuprification), whereas carbonaceous species, Ca-silicates and N-bearing species are detected, the last being tentatively identified as organic (primarily amine-like) residues deriving from the soil. A textured grain, which we qualify as a second phase of bronze originated by an imperfect alloying of the two major metals (i.e., consisting of Cu-rich and Sn-rich domains) is observed on the metallic side lying beneath the patina. SAM imaging with a submicron spatial resolution highlights the presence of SnO2 oxide inside what appears to be the hollow veins of the grain, whereas a Cu2O-like oxide is confined exclusively to the flat regions of the grain. We explain these results by noting that the hollow veins, offering a higher exposure to external fluids. are likely to have promoted preferential formation of the more stable tin oxide over copper oxide. In another region of the metal side we studied the chemistry of grain boundaries and their surrounding areas. We find that S species lie exclusively inside the grain boundaries., whereas Sn and Zn species accumulate just outside the boundary channels, and this lateral chemical inhomogeneity is highlighted with a similar to 200 nm spatial resolution. Lateral segregation of Cu and Sn domains is imaged in another region with a spatial resolution of similar to 15 nm. This result marks the best spatial resolution any analytical method has yet achieved in highlighting chemical heterogeneities of ancient bronzes. Although archaeomaterials lie outside the mainstream applications of Auger techniques, this study provides convincing evidence that SAM can greatly advance our understanding of these materials, as it provides clues relating to corrosion and palmation phenomena. as well as manufacturing processes that are not easily reachable by other microscopies or microanalytical techniques. (C) 2001 American Vacuum Society. C1 CNR, Area Ric Roma, Ist Struttura Mat, I-00133 Rome, Italy. CNR, ICFAM, I-16149 Genoa, Italy. Pacific NW Natl Lab, WR Wiley Environm Mol Sci Lab, Richland, WA 99352 USA. Univ Oxford, Dept Mat, Mat Sci Based Archaeol Grp, Oxford OX5 1PF, England. RP CNR, Area Ric Roma, Ist Struttura Mat, Via Fosso Cavaliere, I-00133 Rome, Italy. EM paparazzo@nameserver.ism.rm.cnr.it RI Baer, Donald/J-6191-2013; OI Baer, Donald/0000-0003-0875-5961; Lea, Alan/0000-0002-4232-1553 NR 25 TC 12 Z9 12 U1 1 U2 8 PU A V S AMER INST PHYSICS PI MELVILLE PA STE 1 NO 1, 2 HUNTINGTON QUADRANGLE, MELVILLE, NY 11747-4502 USA SN 0734-2101 EI 1520-8559 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A PD JUL-AUG PY 2001 VL 19 IS 4 BP 1126 EP 1133 DI 10.1116/1.1349191 PN 1 PG 8 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 456YT UT WOS:000170110900019 ER PT J AU Cuenya, BR Pearson, J Yu, CT Li, DQ Bader, SD AF Cuenya, BR Pearson, J Yu, CT Li, DQ Bader, SD TI Growth and magnetic properties of ultrathin Fe on Pd(110) SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A LA English DT Article; Proceedings Paper CT 47th International Symposium of AVS CY OCT 02-06, 2000 CL BOSTON, MA SP AVS ID SURFACES; FILMS; TRANSITION; NANOWIRES; PD(001); FE(110); W(110); CHAINS AB We have investigated the growth and magnetic properties of 0-3 ML (monolayers) Fe on stepped Pd(110) with reflection high-energy electron diffraction (RHEED), low-energy electron diffraction, and the surface magneto-optic Kerr effect in order to relate the morphology, structure, and magnetic properties in a low-dimensional system. The Fe films grown at 340 K are smooth and pseudomorphic up to 1.5 ML, where three-dimensional growth and lateral lattice relaxation ensues. The in-plane row spacing along the [110] direction decreases by similar to5%-6% at 3 ML. RHEED oscillations with I ML period are observed in the (1,0), (2,0), and the center of the (0,0) streak intensity. The tail of the (0,0) streak at low exit angle, however, has a 0.5 ML period oscillation, which suggests step decoration growth. Submonolayer Fe films remain ferromagnetic above similar to0.3 ML. The magnetic easy axis is initially perpendicular to the surface and is in-plane for Fe thickness > 1.5 ML. Between 0.9 and 1.2 ML, there appear to be mixed magnetic phases as indicated by an increase in coercivity. (C) 2001 American Vacuum Society. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Gerhard Mercator Univ Duisburg, Lab Angew Phys, Duisburg, Germany. RP Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. EM dongqi@anl.gov RI Bader, Samuel/A-2995-2013; Roldan Cuenya, Beatriz/L-1874-2016 OI Roldan Cuenya, Beatriz/0000-0002-8025-307X NR 15 TC 9 Z9 9 U1 0 U2 3 PU A V S AMER INST PHYSICS PI MELVILLE PA STE 1 NO 1, 2 HUNTINGTON QUADRANGLE, MELVILLE, NY 11747-4502 USA SN 0734-2101 EI 1520-8559 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A PD JUL-AUG PY 2001 VL 19 IS 4 BP 1182 EP 1185 DI 10.1116/1.1345912 PN 1 PG 4 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 456YT UT WOS:000170110900028 ER PT J AU Perkins, CL Henderson, MA Peden, CHF Herman, GS AF Perkins, CL Henderson, MA Peden, CHF Herman, GS TI Self-diffusion in ceria SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A LA English DT Article; Proceedings Paper CT 47th International Symposium of AVS CY OCT 02-06, 2000 CL BOSTON, MA SP AVS ID ELECTRONIC-STRUCTURE; SURFACE-DEFECTS; CEO2 SURFACES; OXYGEN; FILMS; TIO2; REDUCTION; WATER; XPS AB Ceria (CeO(2)) is an oxygen storage material vital to the proper functioning of automobile three-way catalysts and is typically viewed as an anion conductor. Prior experimental work using temperature programmed static secondary ion mass spectrometry (TPSSIMS) has indicated that for rutile TiO(2), a prototypical oxide, the mobile species are Ti cations rather than O anions. To further expand on the mobile species in CeO(2) we have investigated the diffusion of both cerium and oxygen ions by TPSSIMS. The CeO(2)( 1 1 1) film was heteroepitaxially grown by molecular beam epitaxy on a yttria stabilized zirconia substrate. Although high quality low-energy electron diffraction patterns and Auger electron spectroscopy spectra free of impurity signals were obtained after just a few sputtering and annealing cycles, further cleaning was necessary to remove intense alkali and alkaline earth signals observed in SSIMS. The CeO(2)(1 1 1) surface was slightly enriched in (18)O by first annealing the film in UHV at 830 K and then exposing the 130 K crystal to (18)O(2). TPSSIMS data in conjunction with temperature programmed desorption data demonstrate that surface oxygen atoms begin to exchange with the bulk around 550 K. Physical deposition of submonolayer amounts of isotopically enriched cerium ((136)Ce) in an (18)O(2) background allowed the simultaneous study of the diffusion of both cerium and oxygen ions. Surface cerium cations were found to be immobile with no diffusion into the bulk for temperatures up to 900 K, the highest temperature studied. (C) 2001 American Vacuum Society. C1 Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Henderson, MA (reprint author), Pacific NW Natl Lab, Environm Mol Sci Lab, POB 999,MS K8-93, Richland, WA 99352 USA. EM ma.henderson@pnl.gov NR 27 TC 34 Z9 34 U1 5 U2 26 PU A V S AMER INST PHYSICS PI MELVILLE PA STE 1 NO 1, 2 HUNTINGTON QUADRANGLE, MELVILLE, NY 11747-4502 USA SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A PD JUL-AUG PY 2001 VL 19 IS 4 BP 1942 EP 1946 DI 10.1116/1.1336831 PN 2 PG 5 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 456YV UT WOS:000170111100074 ER PT J AU Nelson, AJ Reynolds, JG Sanner, RD Coronado, PR Hair, LM AF Nelson, AJ Reynolds, JG Sanner, RD Coronado, PR Hair, LM TI Pt-metal oxide aerogel catalysts: X-ray photoemission investigation SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 47th International Symposium of AVS CY OCT 02-06, 2000 CL BOSTON, MASSACHUSETTS SP AVS ID PLATINUM COMPLEXES; SPECTROSCOPY AB X-ray photoemission spectroscopy was used to study Pt-metal oxide aerogel catalysts that have been developed to respond to increased NOx emissions of lean-burn engines. Lean-burn engines, critical components of low and zero emission vehicles, produce much higher levels of engine-out NOx and current three-way catalytic converters are not sufficient to meet Clean Air Act standards. Platinum catalysts were formed by the reaction of modified Pt coordination compounds with selected transition- metal alkoxides through sot-gel techniques into aerogels. Photoemission measurements of the Pt 4f, Si 2p, Ti 2p, O 1 s, and C 1s core lines were used to evaluate the chemistry of the material after each processing step. Results indicate Pt-O bonding and reduced Pt disbursed in the aerogel. In addition, Si 2p, Ti 2p, and O 1s binding energies indicate an oxo-bridged network structure. (C) 2001 American Vacuum Society. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Nelson, AJ (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 15 TC 1 Z9 1 U1 1 U2 6 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD JUL-AUG PY 2001 VL 19 IS 4 BP 1121 EP 1125 DI 10.1116/1.1380716 PN 1 PG 5 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 456YT UT WOS:000170110900018 ER PT J AU Ying, H Li, TK Maa, JS Zhang, FY Hsu, ST Gao, YF Engelhard, M AF Ying, H Li, TK Maa, JS Zhang, FY Hsu, ST Gao, YF Engelhard, M TI Plasma etching of lead germanate (PGO) ferroelectric thin film SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 47th International Symposium of AVS CY OCT 02-06, 2000 CL BOSTON, MASSACHUSETTS SP AVS ID FABRICATION AB The lead germanate (PGO) thin film has been proposed for FeRAM devices, especially for one transistor ferroelectric memory cell application. To realize such applications, it is important not only to form the PGO thin film, but also to etch/pattern such thin film. In this work, plasma etching of PGO thin films was investigated by using chlorine or fluorine gas chemistries in an electron cyclotron resonance plasma reactor. Etch rates were studied as a function of etching conditions. The results indicated that a chemical effect, rather than a pure physical sputtering, was the dominant factor during the plasma etching of PGO material. It was also found that under the same etching conditions, a Cl-2/Ar chemistry was more effective in PGO etching than a CF4/Ar chemistry. Under the etching conditions studied, there was no obvious plasma etching damage to the composition of the PGO thin films. However, the surface oxygen and chlorine concentration increased after the etching, indicating there might be some etch-induced surface residue. Such residue was thermally unstable, and can be greatly reduced by a postetch anneal in O-2. (C) 2001 American Vacuum Society. C1 Sharp Labs Amer Inc, Camas, WA 98607 USA. Pacific NW Natl Lab, Richland, WA 99352 USA. RP Ying, H (reprint author), Sharp Labs Amer Inc, 5700 NW Pacific Rim Blvd, Camas, WA 98607 USA. RI Engelhard, Mark/F-1317-2010; OI Engelhard, Mark/0000-0002-5543-0812 NR 9 TC 4 Z9 4 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD JUL-AUG PY 2001 VL 19 IS 4 BP 1341 EP 1345 DI 10.1116/1.1355363 PN 1 PG 5 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 456YT UT WOS:000170110900059 ER PT J AU Ott, RD Blue, CA Santella, ML Blau, PJ AF Ott, RD Blue, CA Santella, ML Blau, PJ TI Tribological performance of a novel high wear resistant high SiAl-Si alloy weld overlay SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 47th International Symposium of AVS CY OCT 02-06, 2000 CL BOSTON, MASSACHUSETTS SP AVS ID AL-SI; BEHAVIOR AB A novel process has been developed at Oak Ridge National Laboratory for the production of high silicon (Si) containing aluminum-silicon (Al-Si) alloy weld overlay on Al alloys. The main purpose of the overlay is to improve the wear resistance of the underlying alloy. The process is versatile enough to place the overlay only in critical areas, thus, greatly reducing the cost of a component. Instead of manufacturing a component from expensive high Si content 390 At alloy, the component could be manufactured from an inexpensive alloy, such as 319 At alloy, and the high Si, Al-Si alloy overlay could be placed in essential areas where high wear resistance was required. Test specimens comprised of the high Si, Al-Si alloy overlays on 319 At alloy have been processed to mimic the wear resistance of bulk 390 At alloys. Pin-on-disk wear tests have been performed, following ASTM standards, to quantify the wear resistance of the high Si, AI-Si alloy overlay with that of bulk 390 At alloy. Wear tests have also been performed on bulk 319 At alloy as a baseline. Lubricated and nonlubricated pin-on-disk wear tests were conducted utilizing 440 C stainless steel and 52 100 steel balls as the pin material. Also evaluated were the frictional forces during the wear tests, scratch hardness, microhardness, and the Hertzian contact pressures. From the tests conducted, the high Si, Al-Si alloy overlay shows potential as a replacement of bulk 390 At alloy for high wear resistant applications. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Ott, RD (reprint author), Oak Ridge Natl Lab, POB 2008,1 Bethel Valley Rd, Oak Ridge, TN 37831 USA. NR 14 TC 0 Z9 0 U1 1 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD JUL-AUG PY 2001 VL 19 IS 4 BP 1399 EP 1403 DI 10.1116/1.1339021 PN 1 PG 5 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 456YT UT WOS:000170110900069 ER PT J AU Liu, CA Macrander, A Als-Nielsen, J Zhang, K AF Liu, CA Macrander, A Als-Nielsen, J Zhang, K TI Laterally graded multilayers and their applications SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 47th International Symposium of AVS CY OCT 02-06, 2000 CL BOSTON, MASSACHUSETTS SP AVS ID RAY STANDING WAVES; INTERFACE AB Laterally graded multilayers consisting of uniform W layers and wedge-shaped C layers have been made at the Advanced Photon Source deposition lab for tunable x-ray double-monochromator applications. The double monochromator has two identical graded multilayers in series, as in the conventional double-crystal monochromator arrangement. By letting the x-ray beam hit slightly different (bilayer) d spacing on each multilayer, one can adjust the bandpass and peak energy of the transmitted beam. Also, since the Bragg angles of the two multilayers are not constrained to be the same, the angle of the transmitted beam can be varied in the vertical plane. This option may be an attractive alternative to the conventional way of studying liquid surfaces in reflectivity and grazing-incidence diffraction measurements. The graded multilayer comprised 60 bilayers of W and C on 100 X 25 X 3 min float glass with a d spacing varying from 35 to 60 Angstrom and an average gradient of 0.27 Angstrom /mm in the long direction. The films were made by dc magnetron sputtering with the sputtered atoms passing a contoured mask while the substrate was moving. Two different masks were designed to produce either a uniform (for W) or graded (for C) thickness profile. The multilayer and graded multilayers have many other novel applications. Potential applications in x-ray fluorescence detection and x-ray standing wave experiments will be discussed. (C) 2001 American Vacuum Society. C1 Argonne Natl Lab, User Program Div, Argonne, IL 60439 USA. Univ Copenhagen, Niels Bohr Inst, DK-2100 Copenhagen, Denmark. IIT, Dept Biol Chem & Phys Sci, Chicago, IL 60616 USA. RP Liu, CA (reprint author), Argonne Natl Lab, User Program Div, Argonne, IL 60439 USA. NR 17 TC 15 Z9 15 U1 1 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD JUL-AUG PY 2001 VL 19 IS 4 BP 1421 EP 1424 DI 10.1116/1.1353536 PN 1 PG 4 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 456YT UT WOS:000170110900072 ER PT J AU Windisch, CF Ferris, KF Exarhos, GJ AF Windisch, CF Ferris, KF Exarhos, GJ TI Synthesis and characterization of transparent conducting oxide cobalt-nickel spinel films SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 47th International Symposium of AVS CY OCT 02-06, 2000 CL BOSTON, MASSACHUSETTS SP AVS ID REFLECTANCE AB Cobalt-nickel oxide films of nominal 100 nm thickness, and resistivity on the order of 10(-2) Ohm CM have been deposited by spin casting from both aqueous and organic precursor solutions followed by annealing at 450 degreesC in air. Films deposited on sapphire substrates exhibit a refractive index of about 1.7 and are relatively transparent in the wavelength region from 0.6 to 10.0 mum. They are also magnetic. The electrical and spectroscopic properties of the oxides have been studied as a function Of the x = Co/(Co + Ni) ratio, An increase in film resistivity was found upon substitution of other cations (Zn2+, Al3+,...) for Ni in the spinet structure. However, some improvement in the mechanical properties of the films resulted. A combination of x-ray diffraction, x-ray photoelectron spectroscopy, UV/Vis, and Raman spectroscopy indicated that NiCo2O4 is the primary conducting component and that the conductivity reaches a maximum at this stoichiometry. When x < 0.67, NiO forms leading to an increase in resistivity, when x > 0.67, the oxide was all spinel but the increased Co content lowered the conductivity. The influence of cation charge state and site occupancy in the spinel structure markedly affects calculated electron band structures and likely influences an anomalous switch of p-type conductivity to n-type conductivity seen at x = 0.67. Electronic structure modeling studies also suggest the important role of the Ni3+ cation in the conductivity mechanism. Finally, Raman spectra of the films were relatively easy to obtain and therefore were useful as a routine tool for identifying composition and optimizing conductivity. (C) 2001 American Vacuum Society. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Windisch, CF (reprint author), Pacific NW Natl Lab, Richland, WA 99352 USA. NR 18 TC 59 Z9 61 U1 3 U2 48 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD JUL-AUG PY 2001 VL 19 IS 4 BP 1647 EP 1651 DI 10.1116/1.1351799 PN 2 PG 5 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 456YV UT WOS:000170111100018 ER PT J AU Foerster, CL Lanni, C Foerster, CL AF Foerster, CL Lanni, C Foerster, CL TI Measurements of photon stimulated desorption from thick and thin oxide of KEKB collider copper beam chambers and a stainless steel beam chamber SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 47th International Symposium of AVS CY OCT 02-06, 2000 CL BOSTON, MASSACHUSETTS SP AVS AB Photon stimulated desorption (PSD) from KEKB factory copper chambers was measured at the National Synchrotron Light Source (NSLS), located at the Brookhaven Laboratory. The KEKB is an asymmetrical collider recently constructed in Ibaraki, Japan. The collider utilizes two UHV ring chambers. one for a 3.5 GeV positron beam and the other for an 8 GeV electron beam, for B-meson studies. Two each, 1 m long, 94 mm inner diameter, chemically deoxidized copper beam chambers with conflat end flanges, were provided by KEKB to the NSLS, for measurement of PSD. PSD and specular reflection were measured on NSLS VUV ring beamline U9a. It has been reported that a high temperature air bake on large stainless steel vacuum systems reduces the need for a vacuum bake. To determine the effect of surface oxide, following the initial PSD measurement, the chambers were chemically cleaned and then oxidized in air for a week at 150 degreesC. PSD was remeasured after the air bake. A similar process and measurement was performed on a stainless steel beam chamber, with the exception of oxidation at 450 degreesC. After the chambers were installed on beamline U9a, they were exposed to a minimum of 10(23) photons direct from the source having a critical energy of 595 eV, striking at an incident angle of 100 mrad. The major PSD yields for hydrogen, carbon monoxide, carbon dioxide, methane, and water vapor are reported as a function of accumulated photon flux, incident surface oxide, and chamber preparation. The results are compared with other PSD measurements on NSLS beamlines and those of other laboratory publications for copper and stainless steel. (C) 2001 American Vacuum Society. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. KEK, Tsukuba, Ibaraki 305, Japan. RP Foerster, CL (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. NR 9 TC 1 Z9 1 U1 1 U2 4 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD JUL-AUG PY 2001 VL 19 IS 4 BP 1652 EP 1656 DI 10.1116/1.1340661 PN 2 PG 5 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 456YV UT WOS:000170111100019 ER PT J AU Mapes, M AF Mapes, M TI Summary of quick disconnect vacuum flanges SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 47th International Symposium of AVS CY OCT 02-06, 2000 CL BOSTON, MASSACHUSETTS SP AVS AB In accelerator environments, especially proton machines, high background radiation necessitates the need for quick disconnect vacuum flanges. The use of quick disconnect vacuum flanges significantly reduces the dose of radiation received by workers when installing or removing vacuum chambers in the accelerator. Over the course of many years there have been many designs used for these flanges at Brookhaven National Laboratory for such machines as the Alternating Gradient Synchrotron (AGS), the AGS Booster, and the Relativistic Heavy Ion Collider. Several different flanges with apertures as large as 14 in. in diameter were also evaluated for use in the Spallation Neutron Source project. A summary of various quick connect flanges as well as some commercially available flanges and the evaluation results are presented. (C) 2001 American Vacuum Society. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. RP Mapes, M (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. NR 5 TC 2 Z9 2 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD JUL-AUG PY 2001 VL 19 IS 4 BP 1693 EP 1698 DI 10.1116/1.1359540 PN 2 PG 6 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 456YV UT WOS:000170111100026 ER PT J AU Lee, KP Zhang, AP Dang, G Ren, F Hobson, WS Lopata, J Abenathy, CR Pearton, SJ Lee, JW AF Lee, KP Zhang, AP Dang, G Ren, F Hobson, WS Lopata, J Abenathy, CR Pearton, SJ Lee, JW TI Process development for small-area GaN/AlGaN heterojunction bipolar transistors SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 47th International Symposium of AVS CY OCT 02-06, 2000 CL BOSTON, MASSACHUSETTS SP AVS ID FABRICATION; SIMULATION AB A self-aligned fabrication process for small emitter contact area (2 x 4 mum(2)) GaN/AlGaN heterojunction bipolar transistor is described. The process features dielectric-spacer sidewalls. low damage dry etching, and selected-area regrowth of GaAs(C) on the base contact. The junction current-voltage (I - V) characteristics were evaluated at various stages of the process sequence and provided an excellent diagnostic for monitoring the effect of plasma processes such as chemical vapor deposition or etching. A comparison is given with large emitter-area (1.96 X 10(3) mum(2)) devices fabricated on the same material. The small-area devices are attractive for microwave power switching applications provided a high-yield process can be developed. (C) 2001 American Vacuum Society. C1 Univ Florida, Dept Mat Sci & Engn, Gainesville, FL 32611 USA. Univ Florida, Dept Chem Engn, Gainesville, FL 32611 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. Lucent Technol, Bell Labs, Murray Hill, NJ 07974 USA. Univ Florida, Dept Mat Sci & Engn, Gainesville, FL 32611 USA. Unaxis, St Petersburg, FL 33716 USA. RP Lee, KP (reprint author), Univ Florida, Dept Mat Sci & Engn, Gainesville, FL 32611 USA. NR 11 TC 1 Z9 1 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD JUL-AUG PY 2001 VL 19 IS 4 BP 1846 EP 1849 DI 10.1116/1.1330260 PN 2 PG 4 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 456YV UT WOS:000170111100055 ER PT J AU Kelly, D Lillard, JA Manner, WL Hanrahan, R Paffett, MT AF Kelly, D Lillard, JA Manner, WL Hanrahan, R Paffett, MT TI Surface characterization of oxidative corrosion of U-Nb alloys SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 47th International Symposium of AVS CY OCT 02-06, 2000 CL BOSTON, MASSACHUSETTS SP AVS AB We have studied the relative rates of oxidative corrosion of U-Nb alloys containing 2-8 wt. % Nb, using x-ray photoelectron spectroscopy and depth profiling by sputtered neutrals mass spectroscopy. The alloys have been characterized after exposure to dry and humidified air (up to 50% relative humidity) at temperatures from 25 to 125 degreesC, and after exposure to electrochemical solutions. Oxidation of the U-Nb alloys in a tube furnace results in oxide layers comprised of UO2 and Nb2O5 under all experimental conditions used. The thickness of the oxides increased with treatment time and temperature, but decreased with increasing Nb alloy content. For example, a 48 h treatment at 75 degreesC and 50% relative humidity results in an oxide layer on U-2% Nb that is approximately 1.5 times as thick as that on U-8% Nb. Electrochemical oxidation of U-Nb alloys facilely generated UO3( . nH(2)O) and Nb2O5 layers similar to 1000 Angstrom thick, qualitatively similar to thermal oxidation results. U-Nb alloys electrochemically oxidized at low pH exhibit oxide layers with near-surface regions (50 Angstrom) enhanced in Nb content, as compared to the bulk material. Surface UO3 (. nH(2)O) was not readily reduced upon exposure to molecular D-2; however, D atoms facilely reduced UO3(. nH(2)O) to UO2. C1 Univ Calif Los Alamos Natl Lab, Div Chem, Los Alamos, NM 87545 USA. Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. RP Kelly, D (reprint author), Univ Calif Los Alamos Natl Lab, Div Chem, POB 1663, Los Alamos, NM 87545 USA. NR 12 TC 8 Z9 8 U1 3 U2 12 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD JUL-AUG PY 2001 VL 19 IS 4 BP 1959 EP 1964 DI 10.1116/1.1359548 PN 2 PG 6 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 456YV UT WOS:000170111100077 ER PT J AU Kuznetsova, A Popova, I Zhukov, V Yates, JT Zhou, G Yang, JC Chen, X AF Kuznetsova, A Popova, I Zhukov, V Yates, JT Zhou, G Yang, JC Chen, X TI Making superior corrosion resistant aluminum oxide films using ozone-electrochemical and electron microscopy studies SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 47th International Symposium of AVS CY OCT 02-06, 2000 CL BOSTON, MASSACHUSETTS SP AVS ID OXIDATION; AL(111) AB Aluminum surfaces have been subjected to oxidation at 300 K, using a molecular beam of ozone of 97% purity. An enhancement of the kinetics of oxidation is found compared to oxidation by O-2. The oxide film produced exhibits enhanced corrosion resistance as measured by several electrochemical methods compared to comparable thickness oxide films made by oxygen exposure. Transmission electron microscopy measurements show that the ozone-grown films exhibit small pore sizes and also increased average density as measured by the behavior of the radial distribution function derived from electron diffraction measurements on films made from ozone and oxygen. These effects may be due to the lower oxygen vacancy defect density in films made from ozone. The special properties of ozone-grown aluminum oxide films are preserved even after the films are removed from vacuum and exposed to the atmosphere. (C) 2001 American Vacuum Society. C1 Univ Pittsburgh, Dept Chem, Ctr Surface Sci, Pittsburgh, PA 15260 USA. Univ Pittsburgh, Dept Mat Sci & Engn, Pittsburgh, PA 15261 USA. Argonne Natl Lab, Div Sci Mat, Argonne, IL 60439 USA. RP Kuznetsova, A (reprint author), Univ Pittsburgh, Dept Chem, Ctr Surface Sci, Pittsburgh, PA 15260 USA. NR 14 TC 6 Z9 6 U1 0 U2 3 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD JUL-AUG PY 2001 VL 19 IS 4 BP 1971 EP 1976 DI 10.1116/1.1359536 PN 2 PG 6 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 456YV UT WOS:000170111100079 ER PT J AU Rotenberg, E Kevan, SD AF Rotenberg, E Kevan, SD TI Fermi contours and adsorbate phonon anomalies for Li/Mo(110) and Li/W(110) SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article; Proceedings Paper CT 47th International Symposium of AVS CY OCT 02-06, 2000 CL BOSTON, MASSACHUSETTS SP AVS ID SURFACE; HYDROGEN; W(110); MO(110); ADSORPTION; VIBRATIONS; METALS AB Angle-resolved photoemission was used to measure the Fermi contours of surface-localized states on the Mo(110) and W(110) surfaces with varying amounts of adsorbed lithium. In analogy with recent results for hydrogen adsorbed on the same surfaces, we find that the contours may have sufficient nesting to drive a surface phonon (Kohn) anomaly. The nesting vector along <()over bar>-->(H) over bar (parallel to the <()over bar> azimuth) on Mo(110) at monolayer coverage is measured to be 1.06 +/-0.05 Angstrom (-1), which is compared to recent phonon measurements by electron energy-loss spectra. We also report the variation of this nesting vector as a function of coverage, and show that a more complete understanding of the electron-phonon coupling on these surfaces might be obtained from coverage-dependent measurements of surface phonon dispersion relations. Finally, our results suggest there is even better nesting along the <()over bar>--> (S) over bar direction and that a more pronounced Kohn anomaly might be observed there. (C) 2001 American Vacuum Society. C1 Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. Univ Oregon, Dept Phys, Eugene, OR 97403 USA. RP Rotenberg, E (reprint author), Lawrence Berkeley Natl Lab, MS 2-400 Adv Light Source, Berkeley, CA 94720 USA. RI Rotenberg, Eli/B-3700-2009; Kevan, Stephen/F-6415-2010 OI Rotenberg, Eli/0000-0002-3979-8844; Kevan, Stephen/0000-0002-4621-9142 NR 17 TC 5 Z9 5 U1 0 U2 6 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD JUL-AUG PY 2001 VL 19 IS 4 BP 1983 EP 1987 DI 10.1116/1.1359541 PN 2 PG 5 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 456YV UT WOS:000170111100081 ER PT J AU Datskos, PG Rajic, S Sepaniak, MJ Lavrik, N Tipple, CA Senesac, LR Datskou, I AF Datskos, PG Rajic, S Sepaniak, MJ Lavrik, N Tipple, CA Senesac, LR Datskou, I TI Chemical detection based on adsorption-induced and photoinduced stresses in microelectromechanical systems devices SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B LA English DT Article; Proceedings Paper CT 47th AVS International Symposium CY OCT 02-06, 2000 CL BOSTON, MASSACHUSETTS SP AVS ID CANTILEVER ARRAY; FORCE MICROSCOPY; ARTIFICIAL NOSE; SENSORS; MICROCANTILEVERS; RESOLUTION; SILICON; FILMS AB The recent advent of microelectromechanical systems (MEMS) devices opened up possibilities for chemical detection. Microcantilevers respond to chemical stimuli by undergoing changes in their bending and resonance frequency when molecules adsorb on their surfaces. In our present studies, we extended this concept and studied changes in both the adsorption-induced stress and photoinduced stress as molecules adsorb on the surface of microcantilevers. We found that microcantilevers that have adsorbed molecules will undergo photoinduced bending that depends on the number of adsorbed molecules on the surface. Furthermore, when microcantilevers undergo photoinduced bending, molecules will adsorb on their surface differently. Depending on the photon wavelength used and microcantilever material, the microcantilever can be made to bend by expanding or contracting the irradiated surface. By coating the surface of the microcantilever with a thin chemical layer, chemical specificity for the target chemicals can be achieved. Chemical selectivity can also be altered by selecting appropriate photon wavelengths due to the introduction of surface states in semiconductor MEMS. In fact, choosing a handful of different photon wavelengths, tunable chemical selectivity can be achieved due to differentiated photoinduced response without the need for multiple chemical coatings. We present and discuss our results on MEMS interactions with two isomers of dimethylnaphthalene, tetrachloroethylene, trichloroethylene, diisopropyl methyl phosphonate, and trinitrotoluene. (C) 2001 American Vacuum Society. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Univ Tennessee, Knoxville, TN 37996 USA. Univ Tennessee, Knoxville, TN 37996 USA. EEG Inc, Knoxville, TN 37391 USA. RP Datskos, PG (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. RI Lavrik, Nickolay/B-5268-2011 OI Lavrik, Nickolay/0000-0002-9543-5634 NR 33 TC 50 Z9 50 U1 1 U2 5 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1071-1023 J9 J VAC SCI TECHNOL B JI J. Vac. Sci. Technol. B PD JUL-AUG PY 2001 VL 19 IS 4 BP 1173 EP 1179 DI 10.1116/1.1387082 PG 7 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA 465PD UT WOS:000170598400015 ER PT J AU Montcalm, C Spiller, E Weber, FJ Wedowski, M Folta, JA Gullikson, EM AF Montcalm, C Spiller, E Weber, FJ Wedowski, M Folta, JA Gullikson, EM TI Multilayer coating and test of the optics for two new 10X Microstepper extreme-ultraviolet lithography cameras SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B LA English DT Article ID SCATTERING; SYSTEMS; FLARE AB Two new sets of projection and condenser optics for our prototype 10x reduction extreme-ultraviolet lithography (EUVL) system were coated with Mo/Si multilayers. The coating thickness was graded across the optics by using shadow masks to ensure maximum throughput at all incidence angles in the camera. The overall deviation of the (normalized) wavelength response across the clear aperture of each mirror is negligible, i.e., below 0.005% root mean square for each optic. However. the wavelength mismatch between two optics coated in different runs is up to 0.07 nm. Nevertheless, this is still within the allowed tolerances, and the predicted optical throughput loss in the camera due to such wavelength mismatch is about 4%. EUV reflectances of 63% and 65% were measured around 13.40 mri for the two secondary optics, which is in good agreement with the expected reflectance based on the substrate finish as measured with atomic force microscopy. (C) 2001 American Vacuum Society. C1 Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Ctr Xray Opt, Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Montcalm, C (reprint author), Lawrence Livermore Natl Lab, POB 808,L-395, Livermore, CA 94551 USA. NR 20 TC 9 Z9 10 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1071-1023 J9 J VAC SCI TECHNOL B JI J. Vac. Sci. Technol. B PD JUL-AUG PY 2001 VL 19 IS 4 BP 1219 EP 1228 DI 10.1116/1.1381065 PG 10 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA 465PD UT WOS:000170598400021 ER PT J AU Lubyshev, D Liu, WK Stewart, TR Cornfeld, AB Fang, XM Xu, X Specht, P Kisielowski, C Naidenkova, M Goorsky, MS Whelan, CS Hoke, WE Marsh, PF Millunchick, JM Svensson, SP AF Lubyshev, D Liu, WK Stewart, TR Cornfeld, AB Fang, XM Xu, X Specht, P Kisielowski, C Naidenkova, M Goorsky, MS Whelan, CS Hoke, WE Marsh, PF Millunchick, JM Svensson, SP TI Strain relaxation and dislocation filtering in metamorphic high electron mobility transistor structures grown on GaAs substrates SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B LA English DT Article; Proceedings Paper CT 19th North American Conference on Molecular Beam Epitaxy (NAMBE-19) CY OCT 15-18, 2000 CL ARIZONA STATE UNIV, TEMPE, ARIZONA HO ARIZONA STATE UNIV ID BUFFER LAYERS AB Plastic relaxation in metamorphic high electron mobility transistor (MHEMT) structures was investigated by x-ray reciprocal mapping and high-resolution transmission electron microscopy (HRTEM). X-ray data indicates that In(Ga)AlAs M buffers with a linearly graded buffer and an inverse step are completely strain compensated at the buffer-active area interface. HRTEM shows reduction of dislocation density from 10(9) to 10(6) cm(-2) through the M buffer. Optimized MHEMT structures were found to exhibit low rms roughness of around 2 nm and excellent electrical transport properties. MHEMT devices with 0.15 mum gates were fabricated with a transconductance of 710 mS/mm, maximum current of 500 mA/mm, and gate-drain breakdown of 6.6 V. A maximum f(t) value of 118 GHz and a maximum rf gain of 18 dB at 10 GHz were measured at a drain current of 200 mA/mm. (C) 2001 American Vacuum Society. C1 IQE Inc, Bethlehem, PA 18015 USA. Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. Univ Calif Los Angeles, Los Angeles, CA 90095 USA. Raytheon Microelect Ctr, Andover, MA 01810 USA. Univ Michigan, Ann Arbor, MI 49109 USA. USA, Res Lab, College Pk, MD 20740 USA. RP Lubyshev, D (reprint author), IQE Inc, Bethlehem, PA 18015 USA. EM dloubychev@iqep.com NR 10 TC 15 Z9 15 U1 0 U2 5 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1071-1023 J9 J VAC SCI TECHNOL B JI J. Vac. Sci. Technol. B PD JUL-AUG PY 2001 VL 19 IS 4 BP 1510 EP 1514 DI 10.1116/1.1376384 PG 5 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA 465PD UT WOS:000170598400070 ER PT J AU Farrell, HH Lu, J Schultz, BD Denison, AB Palmstrom, CJ AF Farrell, HH Lu, J Schultz, BD Denison, AB Palmstrom, CJ TI GaAs(111)B(root 19X root 19)R23.4 degrees surface reconstruction SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B LA English DT Article; Proceedings Paper CT 28th Annual Conference on the Physics and Chemistry of Semiconductor Interfaces (PCSI-28) CY JAN 07-11, 2001 CL ORLANDO, FLORIDA SP Amer Vacuum Soc, Electr & Mat Processing Div, USN, Off Res, USA, Off Res ID MEAN FREE PATHS; EPITAXIAL-GROWTH; 50-2000-EV RANGE; ELECTRON; GAAS; GAAS(111); ENERGIES; MODEL AB The structure of the GaAs(1 1 1)B(root 19 X root 19)R23.4 degrees surface reconstruction has been determined using x-ray photoelectron spectroscopy and scanning tunneling microscopy. This structure is characterized by the sixfold As crown first found by Biegelsen and co-workers. In addition, we find that both As and Ga atoms occur in antisite positions in the top bilayer, and possibly in underlying layers as well. These antisite atoms are proposed to enhance the island formation involved in the epitaxial growth self-assembling nanostructures, and to interfere with the layer-by-layer growth that characterizes homo-and heteroepitaxy on most GaAs surfaces. Unlike several earlier structures proposed for this reconstruction, we propose that all of the As (Ga) dangling orbitals are filled (empty), consistent with the electron counting rule. (C) 2001 American Vacuum Society. C1 Bechtel BWXT Idaho LLC, Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. Univ Minnesota, Dept Chem Engn & Mat Sci, Minneapolis, MN 55455 USA. RP Farrell, HH (reprint author), Bechtel BWXT Idaho LLC, Idaho Natl Engn & Environm Lab, POB 1625, Idaho Falls, ID 83415 USA. NR 26 TC 13 Z9 13 U1 0 U2 4 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1071-1023 J9 J VAC SCI TECHNOL B JI J. Vac. Sci. Technol. B PD JUL-AUG PY 2001 VL 19 IS 4 BP 1597 EP 1605 DI 10.1116/1.1387460 PG 9 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA 465PD UT WOS:000170598400088 ER PT J AU McKay, HA Feenstra, RM Schmidtling, T Pohl, UW Geisz, JF AF McKay, HA Feenstra, RM Schmidtling, T Pohl, UW Geisz, JF TI Distribution of nitrogen atoms in dilute GaAsN and InGaAsN alloys studied by scanning tunneling microscopy SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B LA English DT Article; Proceedings Paper CT 28th Annual Conference on the Physics and Chemistry of Semiconductor Interfaces (PCSI-28) CY JAN 07-11, 2001 CL ORLANDO, FLORIDA SP Amer Vacuum Soc, Electr & Mat Processing Div, USN, Off Res, USA, Off Res ID MOLECULAR-BEAM EPITAXY; BAND-GAP; PHOTOLUMINESCENCE; GAAS1-XNX; GROWTH AB Nitrogen atoms in the cleaved (110) surfaces of dilute GaAsN and InGaAsN alloys have been studied using cross-sectional scanning tunneling microscopy. The distribution of nitrogen atoms in GaAs0.983N0.017 and In0.04Ga0.96As0.09N0.01 alloys is found to be in agreement with random statistics, with the exception of a small enhancement in the number of [001]-oriented nearest-neighbor pairs. The effects of annealing on In0.04Ga0.96As0.99N0.01 alloys has been studied by scanning tunneling spectroscopy. Spectra display a reduced band gap compared to GaAs but little difference is seen between as-grown versus annealed InGaAsN samples. In addition, voltage dependent imaging has been used to investigate second-plane nitrogen atoms. (C) 2001 American Vacuum Society. C1 Carnegie Mellon Univ, Dept Phys, Pittsburgh, PA 15213 USA. Tech Univ Berlin, D-10623 Berlin, Germany. Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Feenstra, RM (reprint author), Carnegie Mellon Univ, Dept Phys, Pittsburgh, PA 15213 USA. RI Feenstra, Randall/P-2530-2014 OI Feenstra, Randall/0000-0001-7120-5685 NR 18 TC 18 Z9 19 U1 0 U2 4 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1071-1023 J9 J VAC SCI TECHNOL B JI J. Vac. Sci. Technol. B PD JUL-AUG PY 2001 VL 19 IS 4 BP 1644 EP 1649 DI 10.1116/1.1379967 PG 6 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA 465PD UT WOS:000170598400096 ER PT J AU Spencer, FW AF Spencer, FW TI Estimating probability of detection curves from regression data SO MATERIALS EVALUATION LA English DT Article DE probability of detection; regression analysis; reliability statistics; a-hat versus a AB Reliability assessments of nondestructive testing (NDT) techniques are rooted in statistical concepts. However, these concepts are sometimes over-looked, misapplied and misunderstood. Adding to the confusion is the multitude of approaches that often exist in the statistical literature for the same basic problem. This paper reviews fundamental concepts of using regression type data to establish probability of detection (POD) curves. The use of and some common misperceptions about confidence bounds are also discussed. Specific areas of discussion will include components of variation and confidence statements and how these concepts are related to the number of discontinuities in specimen sets and the number and nature of repeat tests. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Spencer, FW (reprint author), Sandia Natl Labs, POB 5800,MS 0829, Albuquerque, NM 87185 USA. NR 7 TC 5 Z9 5 U1 0 U2 0 PU AMER SOC NON-DESTRUCTIVE TEST PI COLUMBUS PA 1711 ARLINGATE LANE PO BOX 28518, COLUMBUS, OH 43228-0518 USA SN 0025-5327 J9 MATER EVAL JI Mater. Eval. PD JUL PY 2001 VL 59 IS 7 BP 866 EP 870 PG 5 WC Materials Science, Characterization & Testing SC Materials Science GA 450YM UT WOS:000169772500006 ER PT J AU Thevuthasan, S Jiang, W Weber, WJ AF Thevuthasan, S Jiang, W Weber, WJ TI Cleaving oxide films using hydrogen implantation SO MATERIALS LETTERS LA English DT Article DE ion scattering; rutherford backscattering spectrometry (RBS); nuclear reaction analysis (NRA); cleaving oxide film; damage accumulation; strontium titanate (SrTiO(3)); hydrogen ID BEAM-AMORPHIZED SRTIO3; SMART-CUT(R) PROCESS; IMPLANTED SRTIO3; EPITAXIAL RECRYSTALLIZATION; INSULATOR FORMATION; SILICON-CARBIDE; SIC LAYER; ION; COIMPLANTATION; EXFOLIATION AB Precise cleaving of oxide films with known thickness using hydrogen implantation and subsequent annealing was investigated using strontium titanate (SrTiO(3)) as a model material. Rutherford backscattering in channeling geometry (RBS/C), nuclear reaction analysis (NRA), and scanning electron microscopy (SEM) have been used to characterize this process. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Thevuthasan, S (reprint author), Pacific NW Natl Lab, Environm Mol Sci Lab, POB 999,MSIN K8-93, Richland, WA 99352 USA. EM theva@pnl.gov RI Weber, William/A-4177-2008; OI Weber, William/0000-0002-9017-7365; Jiang, Weilin/0000-0001-8302-8313 NR 29 TC 10 Z9 10 U1 1 U2 7 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-577X J9 MATER LETT JI Mater. Lett. PD JUL PY 2001 VL 49 IS 6 BP 313 EP 317 DI 10.1016/S0167-577X(00)00391-8 PG 5 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 451KL UT WOS:000169801200001 ER PT J AU Fugate, ML Sohn, H Farrar, CR AF Fugate, ML Sohn, H Farrar, CR TI Vibration-based damage detection using statistical process control SO MECHANICAL SYSTEMS AND SIGNAL PROCESSING LA English DT Article AB Currently, vibration-based damage detection is an area of significant research activity. This paper attempts to extend the research in this field through the application of statistical analysis procedures to the vibration-based damage detection problem. The damage detection process is cast in the context of a statistical pattern recognition paradigm. In particular, this paper focuses on applying statistical process control methods referred to as 'control charts' to vibration-based damage detection. First, an autoregressive (AR) model is fit to the measured acceleration-time histories from an undamaged structure. Residual errors, which quantify the difference between the prediction from the AR model and the actual measured time history at each time interval, are used as the damage-sensitive features. Next, the X-bar and S control charts are employed to monitor the mean and variance of the selected features. Control limits for the control charts are constructed based on the features obtained from the initial intact structure. The residual errors computed from the previous AR model and subsequent new data are then monitored relative to the control limits. A statistically significant number of error terms outside the control limits indicate a system transit from a healthy state to a damage state. For demonstration, this statistical process control is applied to vibration test data acquired from a concrete bridge column as the column is progressively damaged. (C) 2001 Academic Press. C1 Los Alamos Natl Lab, CIC Div, Comp Res & Applicat Grp, Los Alamos, NM 87545 USA. Los Alamos Natl Lab, Engn Sci & Applicat Div, Engn Anal Grp, ESA EA, Los Alamos, NM 87545 USA. RP Fugate, ML (reprint author), Los Alamos Natl Lab, CIC Div, Comp Res & Applicat Grp, MS B 265, Los Alamos, NM 87545 USA. NR 13 TC 106 Z9 116 U1 2 U2 17 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0888-3270 J9 MECH SYST SIGNAL PR JI Mech. Syst. Signal Proc. PD JUL PY 2001 VL 15 IS 4 BP 707 EP 721 DI 10.1006/mssp.2000.1323 PG 15 WC Engineering, Mechanical SC Engineering GA 459QD UT WOS:000170261400005 ER PT J AU Florakis, A Fassois, SD Hemez, FM AF Florakis, A Fassois, SD Hemez, FM TI MIMO LMS-ARMAX identification of vibrating structures - Part II: A critical assessment SO MECHANICAL SYSTEMS AND SIGNAL PROCESSING LA English DT Article AB In this part of the paper, a critical assessment of the MIMO (multiple-input multiple-output) LMS-ARMAX method is presented, along with comparisons with a pure ARX version and the Eigensystem Realisation Algorithm (ERA) based upon two-input three-output vibration data obtained from a scale aircraft skeleton structure. This structure is characterised by light (zeta < 1%) damping and seven modes within the considered frequency range, two of which are closely spaced and another is a 'local' tail mode. The study focuses on the: (i) ability of the methods to handle higher-dimensional problems, (ii) ability to estimate closely spaced and 'local' modes. (iii) ability to accurately estimate light modal damping, (iv) required model overdetermination, (v) distinction of structural from 'extraneous' modes, (vi) effects of various (white/colour) noise environments, and (vii) suitability of various discrete-time representations for effective identification. The LMS-ARMAX method is shown to be effective, achieving high accuracy in all considered cases. Its various features, such as the stochastic ARMAX representation, the guaranteed stability version, the modest computational complexity and the digital dispersion analysis, are of critical importance. Compared to the pure ARX version, the LMS-ARMAX method is shown to lead to more parsimonious representations and overall better model fits. The ERA is shown to lag behind in terms of overall performance, leading to somewhat lower accuracy, in particular for the two closely spaced modes, and encountering difficulties in distinguishing structural modes via the modal amplitude coherence (MAC). (C) 2001 Academic Press. C1 Univ Patras, Dept Mech & Aeronaut Engn, Stochast Mech Syst Grp, GR-26500 Patras, Greece. Los Alamos Natl Lab, ESA EA, Los Alamos, NM 87545 USA. RP Florakis, A (reprint author), Univ Patras, Dept Mech & Aeronaut Engn, Stochast Mech Syst Grp, GR-26500 Patras, Greece. NR 8 TC 22 Z9 24 U1 0 U2 2 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0888-3270 J9 MECH SYST SIGNAL PR JI Mech. Syst. Signal Proc. PD JUL PY 2001 VL 15 IS 4 BP 737 EP 758 DI 10.1006/mssp.2000.1385 PG 22 WC Engineering, Mechanical SC Engineering GA 459QD UT WOS:000170261400007 ER PT J AU Siantar, CLH Walling, RS Daly, TP Faddegon, B Albright, N Bergstrom, P Chuang, C Garrett, D House, RK Knapp, D Wieczorek, DJ Verhey, LJ AF Siantar, CLH Walling, RS Daly, TP Faddegon, B Albright, N Bergstrom, P Chuang, C Garrett, D House, RK Knapp, D Wieczorek, DJ Verhey, LJ TI Description and dosimetric verification of the PEREGRINE Monte Carlo dose calculation system for photon beams incident on a water phantom SO MEDICAL PHYSICS LA English DT Article DE Monte Carlo; radiation therapy; treatment planning; dose calculation ID MEDICAL ACCELERATORS; ELECTRON-TRANSPORT; MONITOR CHAMBER; PHASE-SPACE; DISTRIBUTIONS; RADIOTHERAPY; ALGORITHM; SIMULATION; ENERGY; CODE AB PEREGRINE is a three-dimensional Monte Carlo dose calculation system written specifically for radiotherapy. This paper describes the implementation and overall dosimetric accuracy of PEREGRINE physics algorithms, beam model, and beam commissioning procedure. Particle-interaction data, tracking geometries, scoring, variance reduction, and statistical analysis are described. The BEAM code system is used to model the treatment-independent accelerator head, resulting in the identification of primary and scattered photon sources and an electron contaminant source. The magnitude of the electron source is increased to improve agreement with measurements in the buildup region in the largest fields. Published measurements provide an estimate of backscatter on monitor chamber response. Commissioning consists of selecting the electron beam energy, determining the scale factor that defines dose per monitor unit, and describing treatment-dependent beam modifiers. We compare calculations with measurements in a water phantom for open fields, wedges, blocks, and a multileaf collimator for 6 and 18 MV Varian Clinac 2100C photon beams. All calculations are reported as dose per monitor unit. Aside from backscatter estimates, no additional, field-specific normalization is included in comparisons with measurements. Maximum discrepancies were less than either 2% of the maximum dose or 1.2 mm in isodose position for all field sizes and beam modifiers. (C) 2001 American Association of Physicists in Medicine. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Calif San Francisco, Dept Radiat Oncol, San Francisco, CA 94143 USA. Univ Michigan, Ann Arbor, MI 48109 USA. RP Siantar, CLH (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 52 TC 54 Z9 54 U1 1 U2 7 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0094-2405 J9 MED PHYS JI Med. Phys. PD JUL PY 2001 VL 28 IS 7 BP 1322 EP 1337 DI 10.1118/1.1381551 PG 16 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 454UW UT WOS:000169991000002 ER PT J AU Jones, RH Baer, DR Danielson, MJ Vetrano, JS AF Jones, RH Baer, DR Danielson, MJ Vetrano, JS TI Role of Mg in the stress corrosion cracking of an Al-Mg alloy SO METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE LA English DT Article ID GRAIN-BOUNDARY SEGREGATION; SURFACE SEGREGATION; ALUMINUM-ALLOY; OXIDATION AB The corrosion and stress corrosion cracking (SCC) susceptibility of an A-Mg alloy, AA5083, has been shown to depend on the precipitation of the Mg-rich beta phase, (Al3Mg2), but not the enrichment of elemental Mg at grain boundaries to an enrichment ratio of 1.4. These results were determined by measuring the progress of Mg enrichment at grain boundaries for increasing thermal-treatment times, using auger electron spectroscopy (AES) of grain boundaries exposed by fracture within the spectrometer and by analytical electron microscopy (AEM) of thin foils. The progress of the beta phase precipitation was followed by AEM and scanning electron microscopy (SEM), for the same thermal treatment times. The lack of a Mg-segregation effect on SCC was demonstrated by results obtained with X-ray photoelectron spectroscopy (XPS) analysis of Mg-implanted Al following in-situ electrochemical tests and SCC tests, while the dominance of beta phase precipitation was demonstrated by electrochemical analysis and SCC testing. Crack-growth tests of alloy AA5083 demonstrated faster cracking at potentials anodic to the open circuit potential (OCP) with no increase at potentials cathodic to the OCP. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Jones, RH (reprint author), Pacific NW Natl Lab, Richland, WA 99352 USA. RI Baer, Donald/J-6191-2013 OI Baer, Donald/0000-0003-0875-5961 NR 24 TC 90 Z9 99 U1 3 U2 32 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 JUL PY 2001 VL 32 IS 7 BP 1699 EP 1711 DI 10.1007/s11661-001-0148-0 PG 13 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 450YK UT WOS:000169772300013 ER PT J AU Zhang, Y Haynes, JA Lee, WY Wright, IG Pint, BA Cooley, KM Liaw, PK AF Zhang, Y Haynes, JA Lee, WY Wright, IG Pint, BA Cooley, KM Liaw, PK TI Effects of Pt incorporation on the isothermal oxidation behavior of chemical vapor deposition aluminide coatings SO METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE LA English DT Article ID THERMAL BARRIER COATINGS; SCALE METAL INTERFACE; OXIDE SCALE; PLATINUM; ADHESION; ALLOYS; SEGREGATION; IMPURITY; GROWTH; SULFUR AB The effects of Pt incorporation on the isothermal oxidation and diffusion behavior of low-sulfur aluminide bond coatings were investigated. Aluminide (NiAl) coatings and Pt-modified aluminide (Ni,Pt)Al coatings were synthesized on a low-sulfur, yttrium-free single-crystal Ni-based superalloy by a high-purity, low-activity chemical vapor deposition (CVD) aluminizing procedure. The isothermal oxidation kinetics and scale adhesion behavior of CVD NiAl and (Ni,Pt)Al were compared at 1150 degreesC. Compositional profiles of alloying elements in the NiAl and (Ni,Pt)Al coatings before and after isothermal oxidation were determined by electron microprobe analysis. Platinum did not reduce oxide scale growth kinetics. No significant differences in bulk refractory metal (W, Ta, Re, and Mo) distributions were observed as a result of Pt incorporation. Spallation of the alumina scale and the formation of large voids along the oxide-metal interface were commonly observed over the NiAl coating grain boundaries after 100 hours at 1150 degreesC. In contrast, no spallation of Al2O3 scales occurred on (Ni,Pt)Al coating surfaces or grain boundaries, although the sulfur content in the CVD (Ni,Pt)Al coatings was higher than that of the CVD NiAl coatings. Most significantly, no voids were observed at the oxide-metal interface on (Ni,Pt)Al coating surfaces or cross sections after 200 hours at 1150 degreesC. It was concluded that a major beneficial effect of Pt incorporation on an aluminide coatings oxidation resistance is the elimination of void growth at the oxide-metal interface, likely by mitigation of detrimental sulfur effects. C1 Univ Tennessee, Dept Mat Sci & Engn, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Stevens Inst Technol, Dept Chem Biochem & Mat Engn, Hoboken, NJ 07030 USA. RP Zhang, Y (reprint author), Tennessee Technol Univ, Ctr Mfg Res, Cookeville, TN 38505 USA. RI Pint, Bruce/A-8435-2008 OI Pint, Bruce/0000-0002-9165-3335 NR 54 TC 89 Z9 89 U1 4 U2 38 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 JUL PY 2001 VL 32 IS 7 BP 1727 EP 1741 DI 10.1007/s11661-001-0150-6 PG 15 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 450YK UT WOS:000169772300015 ER PT J AU Welten, KC Bland, PA Russell, SS Grady, MM Caffee, MW Masarik, J Jull, AJT Weber, HW Schultz, L AF Welten, KC Bland, PA Russell, SS Grady, MM Caffee, MW Masarik, J Jull, AJT Weber, HW Schultz, L TI Exposure age, terrestrial age and pre-atmospheric radius of the Chinguetti mesosiderite: Not part of a much larger mass SO METEORITICS & PLANETARY SCIENCE LA English DT Article ID RAY PRODUCTION-RATES; IRON-METEORITES; NOBLE-GASES; CHONDRITES; HISTORIES AB We measured the concentrations of the cosmogenic radionuclides C-14 (half-life = 5.73 x 10(3) years) in the bulk and of Be-10 (1.5 x 10(6) years), Al-26 (7.05 x 10(5) years), Cl-36 (3.01 X 10(5) years) and the light noble gases in metal and stone fractions of the Chinguetti meteorite to investigate the controversial claim that the 4.5 kg mesosiderite is part of a much larger mass in the Mauritanian desert. Based on the Cl-36-Ar-36, Be-10-Ne-21 and Al-26-Ne-21 pairs in the metal fraction, we derive an average cosmic-ray exposure age of 66 +/- 7 Ma. Chinguetti is now the third out of 20 mesosiderites with an exposure age between 60 and 70 Ma. This may be the first hint of a major impact on the parent body of the mesosiderites, which show ages ranging from 10 to 300 Ma (Terribilini et al., 2000). From the C-14-Be-10 pair we derive a terrestrial age of 18 +/- 1 ka, which seems too recent to be consistent with the original description of the main mass having a heavily wind-eroded base, overhung by the upper part of the meteorite. Finally, from the radionuclide concentrations in combination with Monte-Carlo based calculations, we conclude that our sample of Chinguetti was irradiated at a depth of similar to 15 cm in an object not larger than 80 cm in radius. This is the most compelling evidence against the reports that the Chinguetti mesosiderite is a small fragment of a mass 100 m long and 40 m high. C1 Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. Open Univ, Planetary Sci Res Inst, Milton Keynes MK7 6AA, Bucks, England. Nat Hist Museum, Dept Mineral, London SW7 5BD, England. Univ Calif Lawrence Livermore Natl Lab, Ctr Accelerator Mass Spectrometry, Livermore, CA 94551 USA. Comenius Univ, Fac Math & Phys, SK-84215 Bratislava, Slovakia. Univ Arizona, NSF Arizona AMS Facil, Tucson, AZ 85721 USA. Max Planck Inst Chem, D-55128 Mainz, Germany. RP Welten, KC (reprint author), Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. RI Caffee, Marc/K-7025-2015 OI Caffee, Marc/0000-0002-6846-8967 NR 25 TC 9 Z9 10 U1 0 U2 1 PU METEORITICAL SOC PI FAYETTEVILLE PA DEPT CHEMISTRY/BIOCHEMISTRY, UNIV ARKANSAS, FAYETTEVILLE, AR 72701 USA SN 0026-1114 J9 METEORIT PLANET SCI JI Meteorit. Planet. Sci. PD JUL PY 2001 VL 36 IS 7 BP 939 EP 946 PG 8 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 457RZ UT WOS:000170151800007 ER PT J AU Phan, AV Kaplan, T Gray, LJ Adalsteinsson, D Sethian, JA Barvosa-Carter, W Aziz, MJ AF Phan, AV Kaplan, T Gray, LJ Adalsteinsson, D Sethian, JA Barvosa-Carter, W Aziz, MJ TI Modelling a growth instability in a stressed solid SO MODELLING AND SIMULATION IN MATERIALS SCIENCE AND ENGINEERING LA English DT Article ID BOUNDARY INTEGRAL-EQUATIONS; LEVEL SET METHOD; HYPERSINGULAR INTEGRALS; CURVED ELEMENTS; AMORPHOUS SI; FRONTS; GALERKIN; ELASTICITY; ALGORITHMS; CURVATURE AB The growth of crystalline silicon from the amorphous phase in the presence of an applied stress is modelled using advanced numerical methods. The crystal region is modelled as a linear elastic solid and the amorphous as a viscous fluid with a time-dependent viscosity to reflect structural relaxation. Appropriate coupling conditions across the boundary are defined, and both problems are solved using a symmetric-Galerkin boundary integral method. The interface is advanced in time using the level set technique. The results match well with experiments and support the proposed kinetic mechanism for the observed interface growth instability. C1 Oak Ridge Natl Lab, Comp Sci & Mat Div, Oak Ridge, TN 37831 USA. Univ N Carolina, Dept Math, Chapel Hill, NC 27599 USA. Univ Calif Berkeley, Dept Math, Berkeley, CA 94720 USA. HRL Labs, Malibu, CA 90265 USA. Harvard Univ, Div Engn & Appl Sci, Cambridge, MA 02138 USA. RP Phan, AV (reprint author), Oak Ridge Natl Lab, Comp Sci & Mat Div, POB 2008, Oak Ridge, TN 37831 USA. NR 45 TC 17 Z9 17 U1 1 U2 3 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0965-0393 J9 MODEL SIMUL MATER SC JI Model. Simul. Mater. Sci. Eng. PD JUL PY 2001 VL 9 IS 4 BP 309 EP 325 PG 17 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 457AD UT WOS:000170114200005 ER PT J AU Lauer, SA Chatterjee, S Haldar, K AF Lauer, SA Chatterjee, S Haldar, K TI Uptake and hydrolysis of sphingomyelin analogues in Plasmodium falciparum-infected red cells SO MOLECULAR AND BIOCHEMICAL PARASITOLOGY LA English DT Article DE Plasmodium falciparum; malaria; sphingomyelin; neutral sphingomyelinase ID HUMAN MALARIA PARASITE; NEUTRAL SPHINGOMYELINASE; RAT-BRAIN; ERYTHROCYTE-MEMBRANE; PURIFICATION; CHOLESTEROL; ACID; TRANSPORT; NETWORK; CLONING C1 Stanford Univ, Sch Med, Dept Microbiol & Immunol, Stanford, CA 94305 USA. Johns Hopkins Hosp, Dept Pediat, Baltimore, MD 21278 USA. RP Lauer, SA (reprint author), Univ Calif Los Alamos Natl Lab, Div Biosci, MS 888, Los Alamos, NM 87545 USA. RI Haldar, Kasturi/C-6685-2014 FU NIAID NIH HHS [AI39071] NR 35 TC 15 Z9 16 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0166-6851 J9 MOL BIOCHEM PARASIT JI Mol. Biochem. Parasitol. PD JUL PY 2001 VL 115 IS 2 BP 275 EP 281 DI 10.1016/S0166-6851(01)00281-X PG 7 WC Biochemistry & Molecular Biology; Parasitology SC Biochemistry & Molecular Biology; Parasitology GA 451FN UT WOS:000169790600015 PM 11420114 ER PT J AU Boore, JL AF Boore, JL TI Complete mitochondrial genome sequence of the polychaete annelid Platynereis dumerilii SO MOLECULAR BIOLOGY AND EVOLUTION LA English DT Letter DE Platynereis; annelid; mitochondria; evolution; genome ID DNA; PHYLOGENY C1 Univ Michigan, Dept Biol, Ann Arbor, MI 48109 USA. Univ Calif Lawrence Livermore Natl Lab, Walnut Creek, CA USA. RP Boore, JL (reprint author), DOE Joint Genome Inst, 2800 Mitchell Dr, Walnut Creek, CA 95498 USA. NR 18 TC 50 Z9 55 U1 0 U2 4 PU SOC MOLECULAR BIOLOGY EVOLUTION PI LAWRENCE PA PO BOX 1897, LAWRENCE, KS 66044-8897 USA SN 0737-4038 J9 MOL BIOL EVOL JI Mol. Biol. Evol. PD JUL PY 2001 VL 18 IS 7 BP 1413 EP 1416 PG 4 WC Biochemistry & Molecular Biology; Evolutionary Biology; Genetics & Heredity SC Biochemistry & Molecular Biology; Evolutionary Biology; Genetics & Heredity GA 452FG UT WOS:000169846400024 PM 11420379 ER PT J AU Jung, MK Prigozhina, N Oakley, CE Nogales, E Oakley, BR AF Jung, MK Prigozhina, N Oakley, CE Nogales, E Oakley, BR TI Alanine-scanning mutagenesis of Aspergillus gamma-tubulin yields diverse and novel phenotypes SO MOLECULAR BIOLOGY OF THE CELL LA English DT Article ID SPINDLE POLE BODY; MICROTUBULE DYNAMIC INSTABILITY; SYSTEMATIC MUTATIONAL ANALYSIS; BETA-TUBULIN; RING COMPLEX; MOLECULAR CHARACTERIZATION; SACCHAROMYCES-CEREVISIAE; MITOTIC SPINDLE; NIDULANS; GENE AB We have created 41 clustered charged-to-alanine scanning mutations of the mipA, gamma -tubulin, gene of Aspergillus nidulans and have created strains carrying these mutations by two-step gene replacement and by a new procedure, heterokaryon gene replacement. Most mutant alleles confer a wild-type phenotype, but others are lethal or conditionally lethal. The conditionally lethal alleles, exhibit a variety of phenotypes under restrictive conditions. Most have robust but highly abnormal mitotic spindles and some have abnormal cytoplasmic microtubule arrays. Two alleles appear to have reduced amounts of gamma -tubulin at the spindle pole bodies and nucleation of spindle microtubule assembly may be partially inhibited. One allele inhibits germ tube formation. The cold sensitivity of two alleles is strongly suppressed by the antimicrotubule agents benomyl and nocodazole and a third allele is essentially dependent on these compounds for growth. Together our data indicate that gamma -tubulin probably carries out functions essential to mitosis and organization of cytoplasmic microtubules in addition to its well-documented role in microtubule nucleation. We have also placed our mutations on a model of the structure of gamma -tubulin and these data give a good initial indication of the functionally important regions of the molecule. C1 Ohio State Univ, Dept Mol Genet, Columbus, OH 43210 USA. Univ Calif Berkeley, Howard Hughes Med Inst, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Cell Biol, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Life Sci, Berkeley, CA 94720 USA. RP Oakley, BR (reprint author), Ohio State Univ, Dept Mol Genet, Columbus, OH 43210 USA. FU NIGMS NIH HHS [GM-31837, R01 GM031837] NR 45 TC 49 Z9 51 U1 0 U2 2 PU AMER SOC CELL BIOLOGY PI BETHESDA PA 8120 WOODMONT AVE, STE 750, BETHESDA, MD 20814-2755 USA SN 1059-1524 J9 MOL BIOL CELL JI Mol. Biol. Cell PD JUL PY 2001 VL 12 IS 7 BP 2119 EP 2136 PG 18 WC Cell Biology SC Cell Biology GA 461DU UT WOS:000170350300017 PM 11452008 ER PT J AU Woloszynska, M Kieleczawa, J Ornatowska, M Wozniak, M Janska, H AF Woloszynska, M Kieleczawa, J Ornatowska, M Wozniak, M Janska, H TI The origin and maintenance of the small repeat in the bean mitochondrial genome SO MOLECULAR GENETICS AND GENOMICS LA English DT Article DE mitochondrial genome; recombination; repeats; substoichiometric molecules; bean evolution ID NICOTIANA-SYLVESTRIS; CHLOROPLAST DNA; RECOMBINATION; PLANT; SEQUENCES; MAIZE; REVERSION; DELETION; MUTANT; GENE AB The genesis of small repeats involved in infrequent recombinations in plant mitochondrial genomes remains unclear. We propose that at least some of the small repeats are generated in a similar way to the large, highly recombinogenic, plant mitochondrial repeats. A 314-bp sequence was detected as a small, rarely recombining mitochondrial repeat in the genus Phaseolus. Two of the recombinational forms were predominant, while two others were found in substoichiometric amounts in the species P. vulgaris, P. polyanthus and P. coccineus. However, the pairs of predominant and substoichiometric forms were distinct in each genome, indicating that a mechanism other than recombination is responsible for their maintenance in high or low copy number. In P. lunatus, which is phylogenetically quite remote from the other species examined, only one form of the 314-bp repeat was predominant, while the other forms were present in substoichiometric amounts. In this genome, we also identified sequences containing the terminal I I or 7 bp of the 314-bp repeat. These configurations could serve as intermediates during generation of the repeat. We presume that two site-specific recombinations between the intermediates and the predominant form found in P. lunatus resulted in creation of the two new forms of the repeat. The fourth form of the repeat appeared after a further recombination that occurred at the substoichiometric level. The nature of this recombination, whether site-specific or homologous, is discussed. Beyond the evident similarities between the model presented in this work and the three-recombination models previously proposed to explain the formation of large, frequently recombining repeats, we did not detect any specific deletion associated with generation of the repeat. C1 Univ Wroclaw, Inst Biochem & Mol Biol, PL-50137 Wroclaw, Poland. Brookhaven Natl Lab, Dept Biol, Upton, NY 11973 USA. RP Janska, H (reprint author), Univ Wroclaw, Inst Biochem & Mol Biol, Ul Tamka 2, PL-50137 Wroclaw, Poland. NR 26 TC 15 Z9 15 U1 1 U2 5 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 1617-4615 J9 MOL GENET GENOMICS JI Mol. Genet. Genomics PD JUL PY 2001 VL 265 IS 5 BP 865 EP 872 PG 8 WC Biochemistry & Molecular Biology; Genetics & Heredity SC Biochemistry & Molecular Biology; Genetics & Heredity GA 461JW UT WOS:000170362000012 PM 11523803 ER PT J AU Kim, SC Cummings, PT AF Kim, SC Cummings, PT TI Adsorption isotherm of a Lennard-Jones nitrogen in a carbon slitlike pore SO MOLECULAR PHYSICS LA English DT Article ID DENSITY-FUNCTIONAL THEORY; PLANAR SLITS; HARD-SPHERES; PERTURBATION-THEORY; PHASE-EQUILIBRIA; FLUIDS; SIMULATIONS; INTERFACES; NANOPORES; CAVITIES AB A density functional perturbation approximation based both on second-order perturbation theory and on the pore average density has been proposed to study the adsorption hysteresis of nitrogen in a carbon slit pore. The main advantage of the present approximation is that it is computationally much simpler than the original density functional approximation based on the second-order perturbation theory of liquids, and can be applied to several model fluids confined in a strong external field in order to study their structural and thermodynamic properties. The calculated adsorption hysteresis for the confined Lennard-Jones nitrogen is in very good agreement with computer simulation, even if its accuracy slightly deteriorates for the desorption branch. The calculated equilibrium particle density distributions also compare well with computer simulations, and are better than those of a density functional theory based on the so-called mean-field approximation. C1 Andong Natl Univ, Dept Phys, Andong 760749, South Korea. Univ Tennessee, Dept Chem Engn, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Chem Technol, Oak Ridge, TN 37831 USA. RP Kim, SC (reprint author), Andong Natl Univ, Dept Phys, Andong 760749, South Korea. RI Cummings, Peter/B-8762-2013 OI Cummings, Peter/0000-0002-9766-2216 NR 27 TC 4 Z9 4 U1 0 U2 1 PU TAYLOR & FRANCIS LTD PI LONDON PA 11 NEW FETTER LANE, LONDON EC4P 4EE, ENGLAND SN 0026-8976 J9 MOL PHYS JI Mol. Phys. PD JUL PY 2001 VL 99 IS 13 BP 1099 EP 1105 PG 7 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 443XK UT WOS:000169368400003 ER PT J AU Jiang, JW Blum, L Bernard, O Prausnitz, JM AF Jiang, JW Blum, L Bernard, O Prausnitz, JM TI Thermodynamic properties and phase equilibria of charged hard sphere chain model for polyelectrolyte solutions SO MOLECULAR PHYSICS LA English DT Article ID RESTRICTED PRIMITIVE MODEL; INTEGRAL-EQUATION THEORY; OPTIMIZED CLUSTER EXPANSIONS; MODIFIED POISSON-BOLTZMANN; LIQUID-VAPOR COEXISTENCE; MONTE-CARLO SIMULATIONS; LENNARD-JONES FLUID; IONIC FLUIDS; FLEXIBLE POLYELECTROLYTES; ASYMMETRIC ELECTROLYTES AB A recent thermodynamic perturbation theory for flexible polyelectrolyte solutions is extended to study thermodynamic properties and phase equilibria for polyelectrolyte solutions with different polyion chain lengths. Osmotic pressure, activity coefficient of an individual ion (polyion or counterion) and average activity coefficient are calculated. Except for the activity coefficient of the polyion, the chain length dependence of the properties is small. Also presented are vapour-liquid equilibrium coexisting curves, vapour pressures and critical points. As the polyion chain length approaches infinity the critical properties (temperature, pressure and density) become constants. C1 Univ S Carolina, Dept Chem & Biochem, Columbia, SC 29208 USA. Univ Puerto Rico, Dept Phys, Rio Piedras, PR 00931 USA. Univ Paris 06, Lab Liquides Ion & Interfaces Chargees, F-75252 Paris, France. Univ Calif Berkeley, Dept Chem Engn, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA. RP Jiang, JW (reprint author), Univ S Carolina, Dept Chem & Biochem, Columbia, SC 29208 USA. RI JIANG, Jianwen/G-1505-2013; OI Jiang, Jianwen/0000-0003-1310-9024 NR 60 TC 41 Z9 41 U1 0 U2 11 PU TAYLOR & FRANCIS LTD PI LONDON PA 11 NEW FETTER LANE, LONDON EC4P 4EE, ENGLAND SN 0026-8976 J9 MOL PHYS JI Mol. Phys. PD JUL PY 2001 VL 99 IS 13 BP 1121 EP 1128 PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 443XK UT WOS:000169368400005 ER PT J AU Setlow, JK Albritton, WL Cabrera-Juarez, E AF Setlow, JK Albritton, WL Cabrera-Juarez, E TI Evidence for gene silencing in Haemophilus influenzae SO MUTATION RESEARCH-FUNDAMENTAL AND MOLECULAR MECHANISMS OF MUTAGENESIS LA English DT Article DE gene silencing; RNA polymerase beta-subunit ID DEPENDENT RNA-POLYMERASE; HEMOPHILUS-INFLUENZAE; ESCHERICHIA-COLI; DNA METHYLATION; HISTONE DEACETYLATION; TRICHOSTATIN-A; PROTEIN; TRANSCRIPTION; GEMINIVIRUS; NEUROSPORA AB Evidence for gene silencing of Haemophilus influenzae involved a beta -subunit of RNA polymerase. The gene presumed silenced was rifampin resistance. The evidence that it was silencing, rather than dominance of a rifampin-sensitive marker, was that it took place when the rifampin resistance marker was on both a plasmid and the chromosome, without the presence of a rifampin-sensitive marker, as judged by lack of transformation of a rifampin-resistant cell to rifampin sensitivity by the plasmid. In addition, three compounds that are known to decrease gene silencing in eukaryotes (trichostatin A, sodium butyrate and 5-azacytidine) also decreased the presumed silencing in H. influenzae. Silencing of rifampin-resistant Escherichia coli did not take place with the plasmid from H. influenzae. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Brookhaven Natl Lab, Dept Biol, Upton, NY 11973 USA. RP Setlow, JK (reprint author), Brookhaven Natl Lab, Dept Biol, Upton, NY 11973 USA. NR 36 TC 0 Z9 1 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0027-5107 J9 MUTAT RES-FUND MOL M JI Mutat. Res.-Fundam. Mol. Mech. Mutagen. PD JUL 1 PY 2001 VL 478 IS 1-2 BP 65 EP 74 DI 10.1016/S0027-5107(01)00098-7 PG 10 WC Biotechnology & Applied Microbiology; Genetics & Heredity; Toxicology SC Biotechnology & Applied Microbiology; Genetics & Heredity; Toxicology GA 449EV UT WOS:000169672100005 PM 11406170 ER PT J AU Setlow, JK Haines, D Cabrera-Juarez, E AF Setlow, JK Haines, D Cabrera-Juarez, E TI MucA protein affects spontaneous mutation in a localized region of Haemophilus influenzae SO MUTATION RESEARCH-FUNDAMENTAL AND MOLECULAR MECHANISMS OF MUTAGENESIS LA English DT Article DE MucA protein; Haemophilus influenzae; E. coli ID HEMOPHILUS-INFLUENZAE; ESCHERICHIA-COLI; MUTAGENESIS; REPAIR; DAMAGE; GENES; RD AB A plasmid called pMucA, from a piece of the plasmid pKM101 (Mol. Gen. Genet 167 (1979) 317) cloned in the vector pDM2 (J, Bacteriol. 151 (1982) 1605), caused higher mutation in a local region of Haemophilus influenzae and caused even more mutation there in a strain also containing novC, the latter causing an increase in supercoiling (J. Bacteriol 164 (1985) 525). The novD mutation depressed supercoiling, and also depressed the mutation by pMucA in the local region of the chromosome. Thus, it is clear that supercoiling is an important phenomenon in spontaneous mutation of H. influenzae. The pMucA plasmid caused a number of other phenomena in H. influenzae, induced W mutation (Proc. Natl. Acad. Sci. USA 82 (1985) 7753), decreased W sensitivity of transforming DNA, but not cells, and W-induced recombination of mutants of phage HP1c1. The effect of the MucA protein in mutagenesis of H. influenzae we consider to be due to the introduction of some of the E, coli functions from pKM101, We postulate that the localized mutation caused by the MucA plasmid also involved localization of the plasmid or its coded protein in the same area, resulting from binding to a homologous gene, probably rec-l, very close to the localized region. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Brookhaven Natl Lab, Dept Biol, Upton, NY 11973 USA. RP Setlow, JK (reprint author), Brookhaven Natl Lab, Dept Biol, Upton, NY 11973 USA. NR 24 TC 0 Z9 0 U1 1 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0027-5107 J9 MUTAT RES-FUND MOL M JI Mutat. Res.-Fundam. Mol. Mech. Mutagen. PD JUL 1 PY 2001 VL 478 IS 1-2 BP 75 EP 81 DI 10.1016/S0027-5107(01)00099-9 PG 7 WC Biotechnology & Applied Microbiology; Genetics & Heredity; Toxicology SC Biotechnology & Applied Microbiology; Genetics & Heredity; Toxicology GA 449EV UT WOS:000169672100006 PM 11406171 ER PT J AU Setlow, JK Haines, D Cabrera-Juarez, E AF Setlow, JK Haines, D Cabrera-Juarez, E TI Gyrase mutants affect mutation in a localized region of Haemophilus influenzae SO MUTATION RESEARCH-FUNDAMENTAL AND MOLECULAR MECHANISMS OF MUTAGENESIS LA English DT Article DE Haemophilus influenzae; DNA supercoiling; nov gene mutation ID ALTERS DNA CONFORMATION; ESCHERICHIA-COLI K-12; HEMOPHILUS-INFLUENZAE; DEOXYRIBONUCLEIC-ACID; RECA MUTANTS; MUTAGENESIS; REPAIR; RECOMBINATION; PROTEASE; GENE AB Spontaneous mutation was greatly increased in a localized region of the chromosome of Haemophilus influenzae, but not at other loci, by a nov gene mutation called novC that increased DNA supercoiling. Another nov gene mutation, called novD, decreased spontaneous mutation in the same localized region and depressed DNA supercoiling. Both mutations, which code for the gyrase B subunit, have been cloned, and the cloned versions also altered mutagenesis and supercoiling in a similar fashion as the two mutations on the chromosome, although novC on the plasmid caused somewhat less mutation than on the chromosome. We postulate that the effects of the gyrase B mutations on the chromosome result from their effects on supercoiling because of increased gyrase near its site of production. The fact that the novC on a plasmid does not cause mutagenesis except in the same localized region that is altered by this mutation on the chromosome, is difficult to explain. One possibility is that there is a complex of proteins in this region which is necessary for the effects on supercoiling and thus, also on mutagenesis. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Brookhaven Natl Lab, Dept Biol, Upton, NY 11973 USA. RP Setlow, JK (reprint author), Brookhaven Natl Lab, Dept Biol, Upton, NY 11973 USA. NR 39 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0027-5107 J9 MUTAT RES-FUND MOL M JI Mutat. Res.-Fundam. Mol. Mech. Mutagen. PD JUL 1 PY 2001 VL 478 IS 1-2 BP 83 EP 88 DI 10.1016/S0027-5107(01)00122-1 PG 6 WC Biotechnology & Applied Microbiology; Genetics & Heredity; Toxicology SC Biotechnology & Applied Microbiology; Genetics & Heredity; Toxicology GA 449EV UT WOS:000169672100007 PM 11406172 ER PT J AU Michalet, X AF Michalet, X TI Stretching single-stranded DNA on a surface SO NANO LETTERS LA English DT Article ID B-DNA; MOLECULES; FORCE AB A sufficiently long strand of DNA bends and balls up, like any other polymer longer than its persistence length. The ability to stretch a DNA molecule lengthwise on a substrate has garnered a great deal of attention in the past several years. There has been notable success in stretching double-stranded DNA (dsDNA), but it is more difficult to stretch single-stranded DNA (ssDNA), both because of the very short persistence length and because it is very "sticky," and attaches nonspecifically to surfaces. In this issue of Nano Letters, Woolley and Kelly present a new method for stretching single-stranded DNA strands on surfaces. C1 Univ Calif Berkeley, Mat Sci & Biophys Sci Div, Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Michalet, X (reprint author), Univ Calif Berkeley, Mat Sci & Biophys Sci Div, Lawrence Berkeley Natl Lab, 1 Cyclotron Rd,MS 2-305, Berkeley, CA 94720 USA. RI Michalet, Xavier/A-9704-2009 OI Michalet, Xavier/0000-0001-6602-7693 NR 18 TC 14 Z9 15 U1 0 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1530-6984 J9 NANO LETT JI Nano Lett. PD JUL PY 2001 VL 1 IS 7 BP 341 EP 343 DI 10.1021/nl010035c PG 3 WC Chemistry, Multidisciplinary; Chemistry, Physical; Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Chemistry; Science & Technology - Other Topics; Materials Science; Physics GA 519JD UT WOS:000173721300001 ER PT J AU Li, LS Hu, JT Yang, WD Alivisatos, AP AF Li, LS Hu, JT Yang, WD Alivisatos, AP TI Band gap variation of size- and shape-controlled colloidal CdSe quantum rods SO NANO LETTERS LA English DT Article ID DOTS; NANOCRYSTALS; ABSORPTION; CRYSTALLITES; POLARIZATION; DEPENDENCE; ASSIGNMENT; EXCITON AB We report the band gaps of rodlike CdSe quantum dots with diameter varying from 3.0 to 6.5 nm and length from 7.5 to 40 nm. A qualitative explanation for the dependence of band gap on width and length is presented. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Alivisatos, AP (reprint author), Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. RI Alivisatos , Paul /N-8863-2015 OI Alivisatos , Paul /0000-0001-6895-9048 NR 18 TC 433 Z9 439 U1 6 U2 80 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1530-6984 J9 NANO LETT JI Nano Lett. PD JUL PY 2001 VL 1 IS 7 BP 349 EP 351 DI 10.1021/nl015559r PG 3 WC Chemistry, Multidisciplinary; Chemistry, Physical; Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Chemistry; Science & Technology - Other Topics; Materials Science; Physics GA 519JD UT WOS:000173721300003 ER PT J AU Wojciak, JM Clubb, RT AF Wojciak, JM Clubb, RT TI Finding the function buried in SAND SO NATURE STRUCTURAL BIOLOGY LA English DT Article ID DNA-BINDING DOMAINS; NUCLEAR-BODY; PROTEIN; TRANSCRIPTION; COMPLEX; CLASSIFICATION; CONTAINS; PROMOTER; ELEMENT; FINGER AB The SAND domain is present in many proteins that have been linked to chromatin-dependent transcriptional regulation and human disease, but their function has remained unknown. Recent studies have revealed that these modules are DNA binding domains of novel molecular structure. C1 Univ Calif Los Angeles, Dept Chem & Biochem, Inst Mol Biol, Los Angeles, CA 90095 USA. Univ Calif Los Angeles, UCLA DOE Lab Struct Biol & Mol Med, Los Angeles, CA 90095 USA. RP Wojciak, JM (reprint author), Univ Calif Los Angeles, Dept Chem & Biochem, Inst Mol Biol, 405 Hilgard Ave, Los Angeles, CA 90095 USA. NR 22 TC 7 Z9 9 U1 0 U2 0 PU NATURE AMERICA INC PI NEW YORK PA 345 PARK AVE SOUTH, NEW YORK, NY 10010-1707 USA SN 1072-8368 J9 NAT STRUCT BIOL JI Nat. Struct. Biol. PD JUL PY 2001 VL 8 IS 7 BP 568 EP 570 DI 10.1038/89582 PG 3 WC Biochemistry & Molecular Biology; Biophysics; Cell Biology SC Biochemistry & Molecular Biology; Biophysics; Cell Biology GA 446JE UT WOS:000169509500002 PM 11427878 ER PT J AU De Santi, S de Leon, MJ Rusinek, H Convit, A Tarshish, CY Roche, A Tsui, WH Kandil, E Boppana, M Daisley, K Wang, GJ Schlyer, D Fowler, J AF De Santi, S de Leon, MJ Rusinek, H Convit, A Tarshish, CY Roche, A Tsui, WH Kandil, E Boppana, M Daisley, K Wang, GJ Schlyer, D Fowler, J TI Hippocampal formation glucose metabolism and volume losses in MCI and AD SO NEUROBIOLOGY OF AGING LA English DT Review DE PET; MRI; mild cognitive impairment; early diagnosis of Alzheimer's disease hippocampal formation ID POSITRON-EMISSION-TOMOGRAPHY; MILD COGNITIVE IMPAIRMENT; EARLY ALZHEIMERS-DISEASE; TEMPORAL-LOBE; ENTORHINAL CORTEX; MEMORY IMPAIRMENT; SENILE DEMENTIA; NEUROFIBRILLARY CHANGES; IMAGE REGISTRATION; CEREBRAL-CORTEX AB We used MRI volume sampling with coregistered and atrophy corrected FDG-PET scans to test three hypotheses: 1) hippocampal formation measures are superior to temporal neocortical measures in the discrimination of normal (NL) and mild cognitive impairment (MCI); 2) neocortical measures are most useful in the separation of Alzheimer disease (AD) from NL or MCI: 3) measures of PET glucose metabolism (MRglu) have greater diagnostic sensitivity than MRI volume. Three groups of age, education, and gender matched NL, MCI, and AD subjects were studied. The results supported the hypotheses: 1)entorhinal cortex MRglu and hippocampal volume were most accurate in classifying NL and MCI: 3) both imaging modalities identified the temporal neocortex as best separating MCI and AD, whereas widespread changes accurately classified NL and AD: 3) In most between group comparisons regional MRglu measures were diagnostically superior to volume measures. These cross-sectional data show that in MCI hippocampal formation changes exist without significant neocortical changes. Neocortical changes best characterize AD. In both MCI and ADI metabolism reductions exceed volume losses. (C) 2001 Elsevier Science Inc. All rights reserved. C1 NYU, Sch Med, Dept Psychiat, New York, NY 10012 USA. NYU, Sch Med, Dept Radiol, New York, NY USA. Nathan S Kline Inst Psychiat Res, Orangeburg, NY 10962 USA. Brookhaven Natl Lab, Dept Med, Upton, NY 11973 USA. Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. RP De Santi, S (reprint author), NYU, Sch Med, Dept Psychiat, 550 1St Ave, New York, NY 10012 USA. FU NIA NIH HHS [AG12101, AG13616, AG08051] NR 100 TC 341 Z9 347 U1 1 U2 14 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0197-4580 J9 NEUROBIOL AGING JI Neurobiol. Aging PD JUL-AUG PY 2001 VL 22 IS 4 BP 529 EP 539 DI 10.1016/S0197-4580(01)00230-5 PG 11 WC Geriatrics & Gerontology; Neurosciences SC Geriatrics & Gerontology; Neurosciences & Neurology GA 453JF UT WOS:000169912200002 PM 11445252 ER PT J AU Nordahl, TE Carter, CS Salo, RE Kraft, L Baldo, J Salamat, S Robertson, L Kusubov, N AF Nordahl, TE Carter, CS Salo, RE Kraft, L Baldo, J Salamat, S Robertson, L Kusubov, N TI Anterior cingulate metabolism correlates with stroop errors in paranoid schizophrenia patients SO NEUROPSYCHOPHARMACOLOGY LA English DT Article DE PET; regional glucose metabolism; anterior cingulate; stroop task; noradrenergic; dopaminergic ID POSITRON EMISSION TOMOGRAPHY; EVENT-RELATED FMRI; SELECTIVE ATTENTION; IRRELEVANT INFORMATION; ALZHEIMERS-DISEASE; LOCUS COERULEUS; CORTEX; FLUORODEOXYGLUCOSE; NOREPINEPHRINE; HUMANS AB Using [O-15]-H2O PET Carter et al. (1997) reported that medicated patients with schizophrenia performing computerized single trial Stroop (1935) showed a reduction in the anterior cingulate activation response to the more attention demanding, incongruent Stroop condition. In that study, both patients and controls also showed a direct correlation between anterior cingulate activation and errors committed during incongruent trials of the task. In this study we follow up with an examination of paranoid schizophrenia outpatients and controls with very high resolution positron emission tomography (PET) and the longer half-life tracer [F-18]-fluorinated deoxyglucose (FDG) (Valk et al. 1990). All subjects (10 controls and 9 paranoid schizophrenia patients) were studied with FDG-PET while performing a computerized trial-by-trial version of the Stroop task during the uptake phase of the tracer (Carter et al. 1992). Results: As in previous studies using the single trial Stroop, patients were able to perform the task but made move color-naming errors during incongruent trials than controls. The patients in the present study showed a trend towards increased metabolic activity in the right anterior cingulate cortex. In the patient group, but not in controls, the anterior cingulate glucose metabolic rate correlated positively with the total incongruent trial errors. Conclusion: These results are consistent with the hypothesis that the anterior cingulate plays a performance-monitoring role during human cognition. This study does not rule out a reduction in error sensitivity in this region of the brain in schizophrenia, as other studies have suggested, however the data show that in unmedicated patients with the paranoid subtype this function is preserved to some extent. [Neuropsychopharmacology 25:139-148, 2001] (C) 2001 American College of Neuropsychopharmacology. Published by Elsevier Science Inc. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Funct Imaging, Berkeley, CA 94720 USA. Univ Calif Davis, Dept Psychiat, Davis, CA USA. Univ Pittsburgh, Med Ctr, Western Psychiat Inst & Clin, Pittsburgh, PA USA. Univ Wisconsin, Ctr Clin Sci, Dept Surg Pathol, Madison, WI USA. VA No Calif Hlth Care Syst, Martinez, CA 94553 USA. Dept Vet Adm Med Ctr, Martinez, CA 94553 USA. RP Nordahl, TE (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Funct Imaging, 55-121,1 Cyclotron Rd, Berkeley, CA 94720 USA. RI Nordahl, Thomas/J-7643-2013 OI Nordahl, Thomas/0000-0002-8627-0356 FU NIMH NIH HHS [MH 46990] NR 44 TC 50 Z9 51 U1 3 U2 4 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0893-133X J9 NEUROPSYCHOPHARMACOL JI Neuropsychopharmacology PD JUL PY 2001 VL 25 IS 1 BP 139 EP 148 DI 10.1016/S0893-133X(00)00239-6 PG 10 WC Neurosciences; Pharmacology & Pharmacy; Psychiatry SC Neurosciences & Neurology; Pharmacology & Pharmacy; Psychiatry GA 437YH UT WOS:000169026600012 PM 11377927 ER PT J AU Sewards, TV Sewards, MA AF Sewards, TV Sewards, MA TI Cortical association areas in the gustatory system SO NEUROSCIENCE AND BIOBEHAVIORAL REVIEWS LA English DT Review DE taste; olfaction; flavor; cortex; insula; operculum; macaque ID MEDIAL PREFRONTAL CORTEX; AGRANULAR INSULAR CORTEX; PRIMATE ORBITOFRONTAL CORTEX; ANTERIOR PERIRHINAL CORTEX; CONDITIONED TASTE-AVERSION; ALERT CYNOMOLGUS MONKEY; MACAQUE MONKEY; OLFACTORY-BULB; PARAHIPPOCAMPAL CORTICES; EFFERENT PROJECTIONS AB The existence, location and interrelationships of cortical gustatory association areas in primates and rodents are discussed. Based on previous proposals, and on anatomical, physiological and lesion data, we propose that in addition to primary gustatory cortex, located in primate opercular cortex and rodent granular insular cortex, three association areas exist. A secondary area is located in dysgranular insular cortex, a tertiary area in agranular insular cortex, and the terminus of the cortical gustatory analyzer is located in perirhinal cortex. We propose that the subjective awareness of flavor is most probably due to neuronal activities in agranular insular cortex. (C) 2001 Elsevier Science Ltd. All rights reserved. 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 115 TC 45 Z9 47 U1 1 U2 6 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0149-7634 J9 NEUROSCI BIOBEHAV R JI Neurosci. Biobehav. Rev. PD JUL PY 2001 VL 25 IS 5 BP 395 EP 407 DI 10.1016/S0149-7634(01)00021-5 PG 13 WC Behavioral Sciences; Neurosciences SC Behavioral Sciences; Neurosciences & Neurology GA 481HY UT WOS:000171514900002 PM 11566478 ER PT J AU Furstenau, RV Mecham, DC AF Furstenau, RV Mecham, DC TI System improvements and new experiments in the Advanced Test Reactor, Idaho National Engineering and Environmental Laboratory SO NUCLEAR ENGINEERING AND DESIGN LA English DT Article; Proceedings Paper CT 15th International Conference on Structural Mechanics in Reactor Technology (SMiRT-15) CY AUG 15-20, 1999 CL SEOUL, SOUTH KOREA SP Special Topics Adv Reactors, Div S AB The Test Reactor Area (TRA) located at the US Department of Energy's Idaho National Engineering and Environmental Laboratory (INEEL) was a cornerstone in the development of nuclear technologies during the last half of the 20th century. The INEEL's Advanced Test Reactor (ATR), the third generation of test reactors at the TRA, has base programs planned for the first half of the 21st century. As the role of nuclear technologies unfolds in the coming decades, past and future testing at the ATR will continue to contribute to technical, operational, and public issues facing the industry. System improvements have been completed or planned that will support operation of the ATR for many more decades. Optimal use of the past and future experience base will provide opportunities for continual improvement in reactor operations and performance. New programs at the ATR support plant aging studies for several international sponsors, disposition of excess weapons grade plutonium in MOX fuel, development of proliferation resistant fuels, and increased isotope production. (C) 2001 Elsevier Science B.V. All rights reserved. C1 US DOE, Test Reactor Area, Idaho Falls, ID 83401 USA. Idaho Natl Engn & Environm Lab, Nucl Engn Technol, Idaho Falls, ID 83415 USA. RP Furstenau, RV (reprint author), US DOE, Test Reactor Area, 850 Energy Dr,MS 7135, Idaho Falls, ID 83401 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0029-5493 J9 NUCL ENG DES JI Nucl. Eng. Des. PD JUL PY 2001 VL 207 IS 1 BP 41 EP 48 DI 10.1016/S0029-5493(00)00424-6 PG 8 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 441RD UT WOS:000169242600005 ER PT J AU Taleyarkhan, RP Moraga, F AF Taleyarkhan, RP Moraga, F TI Static and transient cavitation threshold measurements for mercury with dissolved air and helium SO NUCLEAR ENGINEERING AND DESIGN LA English DT Article AB Cavitation onset in mercury is an important aspect affecting operation and safety of accelerator-driven neutron source facilities employing mercury-filled targets. Cavitation in such systems can occur in the bulk and at liquid-structure interfaces under a range of (oscillating pressure) frequencies. Two different apparatus types were designed and utilized for obtaining practically relevant cavitation threshold data. Transient and static cavitation thresholds of mercury as a function of the cover gas (helium or air), fluid temperature and pressure are reported. Both static and transient cavitation onset pressure thresholds were found to increase linearly with cover gas pressure. Additionally, the cavitation threshold as a function of dissolved gases were also measured and found to vary significantly between air and helium. Over the examined range, the effect of fluid temperature was found to be small and within experimental error. (C) 2001 Elsevier Science S.A. All rights reserved. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Oak Ridge Associated Univ, Oak Ridge, TN 37831 USA. RP Taleyarkhan, RP (reprint author), Lockheed Maratin Energy Syst Inc, Engn Technol Div, ERNL, Bldg 9204-1,POB 2009, Oak Ridge, TN 37831 USA. NR 8 TC 7 Z9 7 U1 0 U2 2 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0029-5493 J9 NUCL ENG DES JI Nucl. Eng. Des. PD JUL PY 2001 VL 207 IS 2 BP 181 EP 188 DI 10.1016/S0029-5493(00)00390-3 PG 8 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 430HM UT WOS:000168568500005 ER PT J AU Yamada, H Watanabe, KY Yamazaki, K Murakami, S Sakakibara, S Narihara, K Tanaka, K Osakabe, M Ida, K Ashikawa, N De Vries, PC Emoto, M Funaba, H Goto, M Idei, H Ikeda, K Inagaki, S Inoue, N Isobe, M Kado, S Kaneko, O Kawahata, K Khlopenkov, K Kobuchi, T Komori, A Kubo, S Kumazawa, R Liang, Y Masuzaki, S Minami, T Miyazawa, J Morisaki, T Morita, S Muto, S Mutoh, T Nagayama, Y Nakajima, N Nakamura, Y Nakanishi, H Nishimura, K Noda, N Notake, T Ohdachi, S Ohyabu, N Oka, Y Ozaki, T Pavlichenko, RO Peterson, BJ Rewoldt, G Sagara, A Saito, K Sakamoto, R Sasao, H Sasao, M Sato, K Sato, M Seki, T Shimozuma, T Shoji, M Sugama, H Suzuki, H Takechi, M Takeiri, Y Tamura, N Toi, K Tokuzawa, T Torii, Y Tsumori, K Yamada, I Yamaguchi, S Yamamoto, S Yokoyama, M Yoshimura, Y Watari, T Itoh, K Matsuoka, K Ohkubo, K Ohtake, I Satoh, S Satow, T Sudo, S Tanahashi, S Uda, T Hamada, Y Motojima, O Fujiwara, M AF Yamada, H Watanabe, KY Yamazaki, K Murakami, S Sakakibara, S Narihara, K Tanaka, K Osakabe, M Ida, K Ashikawa, N De Vries, PC Emoto, M Funaba, H Goto, M Idei, H Ikeda, K Inagaki, S Inoue, N Isobe, M Kado, S Kaneko, O Kawahata, K Khlopenkov, K Kobuchi, T Komori, A Kubo, S Kumazawa, R Liang, Y Masuzaki, S Minami, T Miyazawa, J Morisaki, T Morita, S Muto, S Mutoh, T Nagayama, Y Nakajima, N Nakamura, Y Nakanishi, H Nishimura, K Noda, N Notake, T Ohdachi, S Ohyabu, N Oka, Y Ozaki, T Pavlichenko, RO Peterson, BJ Rewoldt, G Sagara, A Saito, K Sakamoto, R Sasao, H Sasao, M Sato, K Sato, M Seki, T Shimozuma, T Shoji, M Sugama, H Suzuki, H Takechi, M Takeiri, Y Tamura, N Toi, K Tokuzawa, T Torii, Y Tsumori, K Yamada, I Yamaguchi, S Yamamoto, S Yokoyama, M Yoshimura, Y Watari, T Itoh, K Matsuoka, K Ohkubo, K Ohtake, I Satoh, S Satow, T Sudo, S Tanahashi, S Uda, T Hamada, Y Motojima, O Fujiwara, M TI Energy confinement and thermal transport characteristics of net current free plasmas in the Large Helical Device SO NUCLEAR FUSION LA English DT Article ID DIMENSIONALLY SIMILAR DISCHARGES; MODE; STELLARATOR; W7-AS AB The energy confinement and thermal transport characteristics of net current free plasmas in regimes with much smaller gyroradii and collisionality than previously studied have been investigated in the Large Helical Device (LHD). The inward shifted configuration, which is superior from the point of view of neoclassical transport theory, has revealed a systematic confinement improvement over the standard configuration. Energy confinement times are improved over the International Stellarator Sealing 95 by a factor of 1.6 +/- 0.2 for an inward shifted configuration. This enhancement is primarily due to the broad temperature profile with a high edge value. A simple dimensional analysis involving LHD and other medium sized heliotrons yields a strongly gyro-Bohm dependence (tau (E)Omega proportional to rho (*-3.8)) of energy confinement times. It should be noted that this result is attributed to a comprehensive treatment of LHD for systematic confinement enhancement and that the medium sized heliotrons have narrow temperature profiles. The core stored energy still indicates a dependence of tau (E)Omega proportional to rho (*-2.6) when data only from LHD are processed. The local heat transport analysis of discharges dimensionally similar except for rho* suggests that the hear conduction coefficient lies between Bohm and gyro-Bohm in the core and changes towards strong gyro-Bohm in the peripheral region. Since the inward shifted configuration has a geometrical feature suppressing neoclassical transport, confinement improvement can be maintained in the collisionless regime where ripple transport is important. The stiffness of the pressure profile coincides with enhanced transport in the peaked density profile obtained by pellet injection. C1 Natl Inst Fus Sci, Toki, Japan. Grad Univ Adv Studies, Dept Fus Sci, Hayama, Japan. Nagoya Univ, Dept Energy Engn & Sci, Nagoya, Aichi, Japan. Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Yamada, H (reprint author), Natl Inst Fus Sci, Toki, 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; Hideo, Sugama/0000-0001-5444-1758 NR 24 TC 53 Z9 53 U1 0 U2 5 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 JUL PY 2001 VL 41 IS 7 BP 901 EP 908 DI 10.1088/0029-5515/41/7/311 PG 8 WC Physics, Fluids & Plasmas SC Physics GA 449KE UT WOS:000169683100011 ER PT J AU Kessel, CE Heitzenroeder, P Jun, C AF Kessel, CE Heitzenroeder, P Jun, C TI Plasma vertical control with internal and external coils in next step tokamaks SO NUCLEAR FUSION LA English DT Article ID INSTABILITY; STABILITY; POSITION; ITER; TCV AB Vertical stability and control are examined for a tokamak configuration intended to be a generic representation of next step devices. Vertical stability calculations show that a critical resistive wall location can be determined for realistic structures and that the introduction of small amounts of low resistivity material to an all steel structure can significantly reduce the vertical instability growth rate. Vertical control simulations show that internal control coils require significantly less feedback power than external coils, and that low resistivity materials can allow either very low feedback powers or coils to be located externally with reasonable feedback powers. C1 Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Kessel, CE (reprint author), Princeton Univ, Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 17 TC 9 Z9 9 U1 0 U2 2 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 JUL PY 2001 VL 41 IS 7 BP 953 EP 961 DI 10.1088/0029-5515/41/7/316 PG 9 WC Physics, Fluids & Plasmas SC Physics GA 449KE UT WOS:000169683100016 ER PT J AU Lindstrom, G Ahmed, M Albergo, S Allport, P Anderson, D Andricek, L Angarano, MM Augelli, V Bacchetta, N Bartalini, P Bates, R Biggeri, U Bilei, GM Bisello, D Boemi, D Borchi, E Botila, T Brodbeck, TJ Bruzzi, M Budzynski, T Burger, P Campabadal, F Casse, G Catacchini, E Chilingarov, A Ciampolini, P Cindro, V Costa, MJ Creanza, D Clauws, P Da Via, C Davies, G De Boer, W Dell'Orso, R De Palma, M Dezillie, B Eremin, V Evrard, O Fallica, G Fanourakis, G Feick, H Focardi, E Fonseca, L Fretwurst, E Fuster, J Gabathuler, K Glaser, M Grabiec, P Grigoriev, E Hall, G Hanlon, M Hauler, F Heising, S Holmes-Siedle, A Horisberger, R Hughes, G Huhtinen, M Ilyashenko, I Ivanov, A Jones, BK Jungermann, L Kaminsky, A Kohout, Z Kramberger, G Kuhnke, M Kwan, S Lemeilleur, F Leroy, C Letheren, M Li, Z Ligonzo, T Linhart, V Litovchenko, P Loukas, D Lozano, M Luczynski, Z Lutz, G MacEvoy, B Manolopoulos, S Markou, A Martinez, C Messineo, A Mikuz, M Moll, M Nossarzewska, E Ottaviani, G Oshea, V Parrini, G Passeri, D Petre, D Pickford, A Pintilie, I Pintilie, L Pospisil, S Potenza, R Raine, C Rafi, JM Ratoff, PN Richter, RH Riedler, P Roe, S Roy, P Ruzin, A Ryazanov, AI Santocchia, A Schiavulli, L Sicho, P Siotis, I Sloan, T Slysz, W Smith, K Solanky, M Sopko, B Stolze, K Avset, BS Svensson, B Tivarus, C Tonelli, G Tricomi, A Tzamarias, S Valvo, G Vasilescu, A Vayaki, A Verbitskaya, E Verdini, P Vrba, V Watts, S Weber, ER Wegrzecki, M Wegrzecka, I Weilhammer, P Wheadon, R Wilburn, C Wilhelm, I Wunstorf, R Wustenfeld, J Wyss, J Zankel, K Zabierowski, P Zontar, D AF Lindstrom, G Ahmed, M Albergo, S Allport, P Anderson, D Andricek, L Angarano, MM Augelli, V Bacchetta, N Bartalini, P Bates, R Biggeri, U Bilei, GM Bisello, D Boemi, D Borchi, E Botila, T Brodbeck, TJ Bruzzi, M Budzynski, T Burger, P Campabadal, F Casse, G Catacchini, E Chilingarov, A Ciampolini, P Cindro, V Costa, MJ Creanza, D Clauws, P Da Via, C Davies, G De Boer, W Dell'Orso, R De Palma, M Dezillie, B Eremin, V Evrard, O Fallica, G Fanourakis, G Feick, H Focardi, E Fonseca, L Fretwurst, E Fuster, J Gabathuler, K Glaser, M Grabiec, P Grigoriev, E Hall, G Hanlon, M Hauler, F Heising, S Holmes-Siedle, A Horisberger, R Hughes, G Huhtinen, M Ilyashenko, I Ivanov, A Jones, BK Jungermann, L Kaminsky, A Kohout, Z Kramberger, G Kuhnke, M Kwan, S Lemeilleur, F Leroy, C Letheren, M Li, Z Ligonzo, T Linhart, V Litovchenko, P Loukas, D Lozano, M Luczynski, Z Lutz, G MacEvoy, B Manolopoulos, S Markou, A Martinez, C Messineo, A Mikuz, M Moll, M Nossarzewska, E Ottaviani, G Oshea, V Parrini, G Passeri, D Petre, D Pickford, A Pintilie, I Pintilie, L Pospisil, S Potenza, R Raine, C Rafi, JM Ratoff, PN Richter, RH Riedler, P Roe, S Roy, P Ruzin, A Ryazanov, AI Santocchia, A Schiavulli, L Sicho, P Siotis, I Sloan, T Slysz, W Smith, K Solanky, M Sopko, B Stolze, K Avset, BS Svensson, B Tivarus, C Tonelli, G Tricomi, A Tzamarias, S Valvo, G Vasilescu, A Vayaki, A Verbitskaya, E Verdini, P Vrba, V Watts, S Weber, ER Wegrzecki, M Wegrzecka, I Weilhammer, P Wheadon, R Wilburn, C Wilhelm, I Wunstorf, R Wustenfeld, J Wyss, J Zankel, K Zabierowski, P Zontar, D TI Radiation hard silicon detectors - developments by the RD48 (ROSE) collaboration SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 4th International Symposium on Development and Application of Semiconductor Tracking Detector CY MAR 22-25, 2000 CL HIROSHIMA, JAPAN SP Murata Fdn Sci Promot DE silicon detectors; radiation hardness; defect engineering; non ionizing energy loss ID NEUTRON-IRRADIATION; DAMAGE AB The RD48 (ROSE) collaboration has succeeded to develop radiation hard silicon detectors. capable to withstand the harsh hadron fluences in the tracking areas of LHC experiments. In order to reach this objective, a defect engineering technique was employed resulting in the development of Oxygen enriched FZ silicon (DOFZ), ensuring the necessary O-enrichment of about 2 x 10(17) O/cm(3) in the normal detector processing. Systematic investigations have been carried out on various standard and oxygenated silicon diodes with neutron, proton and pion irradiation up to a fluence of 5 x 10(14)cm(-2) (1 MeV neutron equivalent). Major focus is on the changes of the effective doping concentration (depletion voltage). Other aspects (reverse current, charge collection) are covered too and the appreciable benefits obtained with DOFZ silicon in radiation tolerance for charged hadrons are outlined. The results are reliably described by the "Hamburg model": its application to LHC experimental conditions is shown, demonstrating the superiority of the defect engineered silicon. Microscopic aspects of damage effects are also discussed. including differences due to charged and neutral hadron irradiation. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Hamburg, D-20146 Hamburg, Germany. Brunel Univ, London, England. Catania Univ, Catania, Italy. Univ Liverpool, Liverpool L69 3BX, Merseyside, England. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Max Planck Inst, Munich, Germany. Univ Perugia, I-06100 Perugia, Italy. Univ Bari, Bari, Italy. Univ Padua, I-35100 Padua, Italy. Univ Glasgow, Glasgow G12 8QQ, Lanark, Scotland. Univ Florence, Florence, Italy. Inst Phys & Technol Mat, Bucharest, Romania. Univ Lancaster, Lancaster LA1 4YW, England. ITE, Warsaw, Poland. Univ Autonoma Barcelona, Ctr Nacl Microelect, E-08193 Barcelona, Spain. Inst Fis Corpuscular, Valencia, Spain. Univ Ljubljana, Jozef Stefan Inst, Ljubljana, Slovenia. Univ Ljubljana, Dept Phys, Ljubljana, Slovenia. Univ Ghent, B-9000 Ghent, Belgium. Kings Coll London, London WC2R 2LS, England. Univ Karlsruhe, Karlsruhe, Germany. Ist Nazl Fis Nucl, Pisa, Italy. Brookhaven Natl Lab, Upton, NY 11973 USA. AF Ioffe Phys Tech Inst, St Petersburg, Russia. STMicroelectronics, Catania, Italy. Inst Nucl Phys, Demokritos, Greece. Univ Calif Berkeley, Dept Mat Sci & Engn, Berkeley, CA 94720 USA. PSI, Villigen, Switzerland. CERN, Geneva, Switzerland. Univ London Imperial Coll Sci Technol & Med, London, England. Czech Tech Univ Prague, CR-16635 Prague, Czech Republic. Univ Montreal, Montreal, PQ, Canada. Acad Sci, Inst Nucl Res, Kiev, Ukraine. ITME, Warsaw, Poland. Univ Modena, I-41100 Modena, Italy. Tel Aviv Univ, Dept Engn, IL-69978 Tel Aviv, Israel. Kurchatov Inst, Moscow, Russia. Acad Sci Czech Republic, Inst Phys, Prague, Czech Republic. CiS Inst Mikrosensor gGmbH, Erfurt, Germany. SINTEF, Oslo, Norway. Royal Inst Technol, Stockholm, Sweden. Inst Nucl Phys & Engn, Bucharest, Romania. Charles Univ Prague, Fac Math & Phys, Inst Nucl & Particle Phys, Prague, Czech Republic. Univ Dortmund, Dortmund, Germany. RP Lindstrom, G (reprint author), Univ Hamburg, Bundesstr 45, D-20146 Hamburg, Germany. EM gunnar.lindstroem@desy.de; gcasse@hep.ph.liv.ac.uk; Marko.Mikuz@ijs.si; rar@hll.mpg.de RI Ruzin, Arie/P-9445-2016; Pintilie, Ioana/C-4545-2011; Vasilescu, Angela/E-9915-2011; Rafi, Joan Marc/D-5500-2012; Focardi, Ettore/E-7376-2012; Grigoriev, Eugene/K-6650-2013; O'Shea, Val/G-1279-2010; Verbitskaya, Elena/D-1521-2014; Campabadal, Francesca/E-6651-2014; Ivanov, Alexander/E-3993-2014; Fonseca, Luis/K-8010-2012; Pintilie, Lucian/D-9475-2011; Bruzzi, Mara/K-1326-2015 OI Passeri, Daniele/0000-0001-5322-2414; Tricomi, Alessia Rita/0000-0002-5071-5501; Wyss, Jeffery/0000-0002-8277-4012; SCHIAVULLI, Luigi/0000-0003-0871-3585; Rafi, Joan Marc/0000-0003-4581-9477; Focardi, Ettore/0000-0002-3763-5267; Grigoriev, Eugene/0000-0001-7235-9715; O'Shea, Val/0000-0001-7183-1205; Campabadal, Francesca/0000-0001-7758-4567; Fonseca, Luis/0000-0002-1394-8074; Pintilie, Lucian/0000-0002-4934-2912; Bruzzi, Mara/0000-0001-7344-8365 NR 27 TC 277 Z9 278 U1 3 U2 39 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 JUL 1 PY 2001 VL 466 IS 2 BP 308 EP 326 DI 10.1016/S0168-9002(01)00560-5 PG 19 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 453JZ UT WOS:000169913900010 ER PT J AU Allport, P Atwood, E Atwood, W Beck, G Bhatnager, B Bloom, E Broeder, J Chen, V Clark, J Cotton, N Silva, EDE Feerick, B Giebels, G Godfrey, G Handa, T Hernando, JA Hirayama, M Johnson, RP Kamae, T Kashiguine, S Kroeger, W Milbury, C Miller, W Millican, O Nikolaou, M Nordby, M Ohsugi, T Paliaga, G Ponslet, E Rowe, W Sadrozinski, HFW Spencer, E Stromberg, S Swensen, E Takayuki, M Tournear, D Webster, A Winkler, G Yamamoto, K Yamamura, K Yoshida, S AF Allport, P Atwood, E Atwood, W Beck, G Bhatnager, B Bloom, E Broeder, J Chen, V Clark, J Cotton, N Silva, EDE Feerick, B Giebels, G Godfrey, G Handa, T Hernando, JA Hirayama, M Johnson, RP Kamae, T Kashiguine, S Kroeger, W Milbury, C Miller, W Millican, O Nikolaou, M Nordby, M Ohsugi, T Paliaga, G Ponslet, E Rowe, W Sadrozinski, HFW Spencer, E Stromberg, S Swensen, E Takayuki, M Tournear, D Webster, A Winkler, G Yamamoto, K Yamamura, K Yoshida, S TI The assembly of the silicon tracker for the GLAST beam test engineering model SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 4th International Sumposium on Development and Application of Semiconductor Tracking Detector CY MAR 22-25, 2000 CL HIROSHIMA, JAPAN SP Murata Fdn Sci Promot DE silicon microstrip detectors; space; gamma-ray AB The silicon tracker for the engineering model of the GLAST Large Area Telescope (LAT) to date represents the largest surface of silicon microstrip detectors assembled in a tracker (2.7 m(2)). It demonstrates the feasibility of employing this technology for satellite based experiments, in which large effective areas and high reliability are required. This note gives an overview of the assembly of this silicon tracker and discusses in detail studies performed to track quality assurance: leakage current, mechanical alignment and production yields. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. Univ Liverpool, Liverpool L69 EBX, Merseyside, England. Univ Calif Santa Cruz, Santa Cruz Inst Particle Phys, Santa Cruz, CA 95064 USA. Univ London Queen Mary & Westfield Coll, London E1 4NS, England. Univ Tokyo, Tokyo 1130033, Japan. Hiroshima Univ, Higashihiroshima 7398526, Japan. Hytec Inc, Los Alamos, NM 87544 USA. Hamamatsu Photon, Hamamatsu, Shizuoka 4308587, Japan. RP Silva, EDE (reprint author), Stanford Linear Accelerator Ctr, MS 98,POB 4349, Stanford, CA 94309 USA. RI Hernando Morata, Jose Angel/L-7642-2014 OI Hernando Morata, Jose Angel/0000-0002-8683-5142 NR 5 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 JUL 1 PY 2001 VL 466 IS 2 BP 376 EP 382 DI 10.1016/S0168-9002(01)00591-5 PG 7 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 453JZ UT WOS:000169913900017 ER PT J AU Iwata, Y Ohsugi, T Ohmoto, T Handa, T Sato, K Yamamoto, H Takashima, R Kondo, T Unno, Y Terada, S Kohriki, T Nakano, I Lindenmeyer, M Tkaczyk, S Erdmann, W Spalding, J Dychakowski, G Bolla, G Pope, G Shepard, P AF Iwata, Y Ohsugi, T Ohmoto, T Handa, T Sato, K Yamamoto, H Takashima, R Kondo, T Unno, Y Terada, S Kohriki, T Nakano, I Lindenmeyer, M Tkaczyk, S Erdmann, W Spalding, J Dychakowski, G Bolla, G Pope, G Shepard, P TI A flexible front-end electronics hybrid for silicon microstrip detectors SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 4th International Sumposium on Development and Application of Semiconductor Tracking Detector CY MAR 22-25, 2000 CL HIROSHIMA, JAPAN SP Murata Fdn Sci Promot ID STRIP MICROVERTEX DETECTOR; VERTEX DETECTOR; READOUT CHIP; CONSTRUCTION; DESIGN AB A new front-end electronics hybrid with a flexible kapton substrate was developed for a silicon microstrip vertex detector. The hybrid showed a noise contribution which is estimated to be 1/35th of a minimum ionizing particle signal. Material thickness of the hybrid is 0.7% of a radiation length. The hybrid front-end electronics was operated in a deadtime-less. analog-pipe-line mode. (C) 2001 Published by Elsevier Science B.V. C1 Hiroshima Univ, Dept Phys, Higashihiroshima, Hiroshima 7398526, Japan. Kyoto Univ Educ, Dept Sci, Kyoto 6120863, Japan. KEK, High Energy Accelerator Res Org, Inst Particle & Nucl Studies, Tsukuba, Ibaraki 3050801, Japan. Okayama Univ, Dept Phys, Okayama 7008530, Japan. Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Pittsburgh, Pittsburgh, PA 15260 USA. RP Iwata, Y (reprint author), Hiroshima Univ, Dept Phys, Higashihiroshima, Hiroshima 7398526, Japan. NR 13 TC 1 Z9 1 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD JUL 1 PY 2001 VL 466 IS 2 BP 390 EP 396 DI 10.1016/S0168-9002(01)00595-2 PG 7 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 453JZ UT WOS:000169913900019 ER PT J AU Bernabeu, J Challis, R Costa, MJ Ferrere, D Gadomski, S Haber, C Hill, J Kaplon, J Lacasta, C Lozano, M Macina, D Martinez, C Moorhead, G Niggli, H Phillips, P Sanchez, J Vos, M Zsenei, A AF Bernabeu, J Challis, R Costa, MJ Ferrere, D Gadomski, S Haber, C Hill, J Kaplon, J Lacasta, C Lozano, M Macina, D Martinez, C Moorhead, G Niggli, H Phillips, P Sanchez, J Vos, M Zsenei, A TI Results of the 1999 H8 beam tests of ATLAS-SCT prototypes SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 4th International Sumposium on Development and Application of Semiconductor Tracking Detector CY MAR 22-25, 2000 CL HIROSHIMA, JAPAN SP Murata Fdn Sci Promot AB During the August-September 1999 test beam in H8 at CERN three half-modules, equipped with different types of fast binary Front End electronics, have been tested. The results indicate that all three SCT electronics candidates satisfy ATLAS efficiency and noise occupancy requirements, Tn addition, a study on the effect of detector bias voltage on efficiency (ballistic deficit) is reported. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Politecn Valencia, CSIC, IFIC, E-46071 Valencia, Spain. Univ Melbourne, Parkville, Vic 3052, Australia. Univ Geneva, CH-1211 Geneva, Switzerland. CERN, CH-1211 Geneva 23, Switzerland. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Cavendish Lab, Cambridge CB3 0HE, England. IMB, CNM, Barcelona, Spain. RP Vos, M (reprint author), Univ Politecn Valencia, CSIC, IFIC, Apartado de Correos 22085, E-46071 Valencia, Spain. RI Moorhead, Gareth/B-6634-2009; Bernabeu, Jose/H-6708-2015 OI Vos, Marcel/0000-0001-8474-5357; Lacasta, Carlos/0000-0002-2623-6252; Moorhead, Gareth/0000-0002-9299-9549; Bernabeu, Jose/0000-0002-0296-9988 NR 7 TC 3 Z9 3 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD JUL 1 PY 2001 VL 466 IS 2 BP 397 EP 405 DI 10.1016/S0168-9002(01)00600-3 PG 9 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 453JZ UT WOS:000169913900020 ER PT J AU Doyle, BL Walsh, DS Renfrow, SN Vizkelethy, G Schenkel, T Hamza, AV AF Doyle, BL Walsh, DS Renfrow, SN Vizkelethy, G Schenkel, T Hamza, AV TI Nuclear emission microscopies SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 7th International Conference on Nuclear Microprobe Technology and Applications CY SEP 10-15, 2000 CL BORDEAUX, FRANCE SP CNRS, CEA, CNRS Univ Bordeaux, CNRS Minist Culture & Commun DE nuclear emission microscopy; ion photon emission microscopy; ion electron emission microscopy; highly charged ion-secondary ion mass spectroscopy ID ION MASS-SPECTROSCOPY; HIGHLY-CHARGED IONS; TIME; SLOW AB Alternatives to traditional nuclear microprobe analysis (NMA) emerged two years ago with the invention of ion electron emission microscopy (IEEM). With nuclear emission microscopy (NEM) the ion beam is only partially focused so as to fill the field of view of a special emission particle microscope system fitted with a single particle position sensitive detector (PSD). When a single ion strikes the sample, the emitted secondaries (e.g. electrons, photons, ions, etc.) are projected at great magnification onto this PSD where position signals are generated. These X and Y signals are then put into coincidence with other signals made by this same ion in a fashion completely analogous to traditional nuclear microprobe analysis. In this paper, an update will be given on the state of NEMs, which currently includes IEEM and highly charged ion-secondary ion mass spectroscopy (HCI-SIMS). In addition, a new type of full-field nuclear imaging is proposed: ion photon emission microscopy or IPEM. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Mission Res Corp, Huntsville, AL USA. Lawrence Berkeley Natl Lab, Berkeley, CA USA. Lawrence Livermore Natl Lab, Livermore, CA USA. RP Doyle, BL (reprint author), Sandia Natl Labs, Org 1111 MS-1056, POB 5000, Albuquerque, NM 87185 USA. NR 17 TC 16 Z9 16 U1 0 U2 4 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 JUL PY 2001 VL 181 BP 199 EP 210 DI 10.1016/S0168-583X(01)00535-3 PG 12 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 470RR UT WOS:000170885400034 ER PT J AU Walsh, DS Dodd, PE Shaneyfelt, MR Schwank, JR AF Walsh, DS Dodd, PE Shaneyfelt, MR Schwank, JR TI Investigation of body-tie effects on ion beam induced charge collection in silicon-on-insulator FETs using the Sandia nuclear microprobe SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 7th International Conference on Nuclear Microprobe Technology and Applications CY SEP 10-15, 2000 CL BORDEAUX, FRANCE SP CNRS, CEA, CNRS Univ Bordeaux, CNRS Minist Culture & Commun DE SOI; body-tie design; single event effects ID SOI AB Silicon-on-insulator (SOI) technology exhibits three main advantages over bulk silicon technology for use in radiation environments. (1) SOI devices are immune to latchup, (2) the volume of the sensitive region (body) and hence total charge collection per transient irradiation is much reduced in SOI devices and (3) the insulating layer blocks charge collection from the substrate (i.e., no funneling effect). This effectively raises the single event upset (SEU) threshold for the SOI device. However, despite their small active volume SOI devices are still vulnerable to single event effects (SEE). Inherent in the SOI transistor design is a parasitic npn bipolar junction transistor (BJT), where the source-body-drain acts as an emitter-base-collector BJT. An ion strike to a floating (not referenced to a specific potential) body creates a condition where the excess minority carriers in the drain-body cause the parasitic BJT to turn on and inject more charge into the drain than was deposited in the device by the ion. In extreme cases the floating body effect (FBE) can trigger a high-current state called single-event snapback (SES) where channel conduction is sustained indefinitely through regenerative electron-impact ionization near the drain junction. Tying the body to the source limits the emitter-base current and reduces the sensitivity of the device to single ion strikes. Unfortunately, the body-tie loses effectiveness with distance due to resistivity, and in regions far enough from the tie the BJT is still in effect. Using the Sandia nuclear microprobe we have created charge collection maps on Sandia CMOS6rs SOI FETs of varying channel widths. These devices have body ties at both ends of the channel region. Results clearly demonstrate that distance of the ion strike from the body tie has an inverse effect upon charge collection and SES sensitivity due to the resistivity of the channel. Experimental results compare well with DAVINCI simulations and electrically induced snapback thresholds. In addition, an interesting saturation effect of SES versus the amount of injected charge is observed. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. EM dswalsh@sandia.gov NR 9 TC 5 Z9 6 U1 0 U2 2 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 JUL PY 2001 VL 181 BP 305 EP 310 DI 10.1016/S0168-583X(01)00486-4 PG 6 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 470RR UT WOS:000170885400051 ER PT J AU Guo, BN El Bouanani, M Renfrow, SN Nigam, M Walsh, DS Doyle, BL Duggan, JL McDaniel, FD AF Guo, BN El Bouanani, M Renfrow, SN Nigam, M Walsh, DS Doyle, BL Duggan, JL McDaniel, FD TI Diffusion-time-resolved ion-beam-induced charge collection from stripe-like test junctions induced by heavy-ion microbeams SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 7th International Conference on Nuclear Microprobe Technology and Applications CY SEP 10-15, 2000 CL BORDEAUX, FRANCE SP CNRS, CEA, CNRS Univ Bordeaux, CNRS Minist Culture & Commun DE heavy-ion microprobe; single-event upset; diffusive charge collection; average arrival time; diffusion-time-resolved ion-beam-induced charge collection ID SINGLE-EVENT UPSET AB To design more radiation-tolerant integrated circuits (ICs), it is necessary to design and test accurate models of ionizing-radiation-induced charge collection dynamics. A new technique, diffusion-time-resolved ion-beam-induced charge collection (DTRIBICC), is used to measure the average arrival time of the diffused charge, which is related to the average time of the arrival carrier density at the junction. Specially designed stripe-like test junctions are studied using a 12 MeV carbon microbeam with a spot size of similar to1 mum. The relative arrival time of ion-generated charge and the collected charge are measured using a multiple parameter data acquisition system. A 2-D device simulation code, MEDICI, is used to calculate the charge collection dynamics on the stripe-like test junctions. The simulations compare well with experimental microbeam measurements. The results show the importance of the diffused charge collection by junctions, which is especially significant for single-event upsets (SEUs) and multiple-event upsets (MEUs) in electronic devices. The charge sharing results also indicate that stripe-like junctions may be used as position-sensitive detectors with a resolution of similar to0.1 mum. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ N Texas, Dept Phys, Ion Beam Modificat & Anal Lab, Denton, TX 76203 USA. Sandia Natl Labs, Ion Beam Mat Res Lab, Albuquerque, NM 87185 USA. RP Univ N Texas, Dept Phys, Ion Beam Modificat & Anal Lab, POB 311427, Denton, TX 76203 USA. EM mcdaniel@unt.edu NR 11 TC 4 Z9 5 U1 0 U2 1 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 JUL PY 2001 VL 181 BP 315 EP 319 DI 10.1016/S0168-583X(01)00488-8 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 470RR UT WOS:000170885400053 ER PT J AU Yang, C Doyle, BL Rossi, P Nigam, M El Bouanani, M Duggan, JL McDaniel, FD AF Yang, C Doyle, BL Rossi, P Nigam, M El Bouanani, M Duggan, JL McDaniel, FD TI Luminescent layers for ion-photon emission microscopy SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 7th International Conference on Nuclear Microprobe Technology and Applications CY SEP 10-15, 2000 CL BORDEAUX, FRANCE SP CNRS, CEA, CNRS Univ Bordeaux, CNRS Minist Culture & Commun DE IBIL; IBICC; ion photon emission microscope; phosphors; luminescence; scanning nuclear microprobe AB Ion beam induced luminescence (IBIL) combined with ion beam induced charge collection (IBICC) is applied in a quantitative study of the IBIL generation yield and detection efficiency for several plastic phosphor materials. The main purpose of this study is to search for strongly luminescence materials that can be used to easily coat samples to be studied with ion-photon emission microscopy (IPEM). A special focus is given to plastic scintillation materials because thin films are easily prepared, and such films have already been used for single event triggering. The emission yield was found to be low for typical Bicron plastic phosphors (only similar to 70 photons/ion/mum). The total collection, transmission and photon detection efficiency of the optical microscope used in this study was determined to be only similar to0.00003. For thin film plastic phosphors similar to 20 mum thick, the detection efficiency was only 0.04 photons/ion. This means that using these plastics, IPEM would need to be performed with similar to 20x more beam fluence to obtain data, such as IBICC, similar to a standard scanned nuclear microprobe. Improvements are discussed. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ N Texas, Dept Phys, Ion Beam Modificat & Anal Lab, Denton, TX 76203 USA. Sandia Natl Labs, Ion Beam Mat Res Lab, Albuquerque, NM 87185 USA. Univ Padua, Dipartimento Fis, I-35131 Padua, Italy. Ist Nazl Fis Nucl, I-35131 Padua, Italy. RP McDaniel, FD (reprint author), Univ N Texas, Dept Phys, Ion Beam Modificat & Anal Lab, POB 311427, Denton, TX 76203 USA. NR 4 TC 12 Z9 12 U1 0 U2 1 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 JUL PY 2001 VL 181 BP 329 EP 334 DI 10.1016/S0168-583X(01)00490-6 PG 6 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 470RR UT WOS:000170885400056 ER PT J AU Cholewa, M Dillon, C Lay, P Phillips, D Talarico, T Lai, B AF Cholewa, M Dillon, C Lay, P Phillips, D Talarico, T Lai, B TI High resolution nuclear and X-ray microprobes and their applications in single cell analysis SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 7th International Conference on Nuclear Microprobe Technology and Applications CY SEP 10-15, 2000 CL BORDEAUX, FRANCE SP CNRS, CEA, CNRS Univ Bordeaux, CNRS Minist Culture & Commun DE nuclear microprobe; X-ray microprobe; cell analysis ID HAMSTER LUNG-CELLS; INTRACELLULAR CHROMIUM; OXIDATION-STATE; COMPLEXES; CYTOTOXICITY; TOXICITY AB Investigations of uptake of different chemical compounds by single cells have become a very popular topic and have been performed with different microanalytical techniques using electron, laser, ion and X-ray beams. With the advent of nuclear microprobes with submicron resolution it has been possible to investigate distribution of different elements inside individual cell with sensitivity of parts-per-million (ppm). Recently, with X-ray beams focused to 150 nm and high intensity obtained from third generation synchrotron facilities it became possible to perform analysis on a single cell with sensitivity of parts-per-billion (ppb). Synchrotron radiation offers also a unique possibility to investigate an oxidation state for different elements. In this paper, authors will present and discuss data from experiments on single cells performed with high resolution nuclear and X-ray microprobes. (C) 2001 Elsevier Science B.-V. All rights reserved. C1 Inst Nucl Phys, PL-31342 Krakow, Poland. Univ Sydney, Sydney, NSW 2006, Australia. La Trobe Univ, Bundoora, Vic 3083, Australia. Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. RP Cholewa, M (reprint author), MF, GSI Mat Res Grp, Planckstr 1, D-64291 Darmstadt, Germany. RI Cholewa, Marian/C-9474-2011; OI Lay, Peter/0000-0002-3232-2720 NR 23 TC 14 Z9 17 U1 0 U2 1 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 JUL PY 2001 VL 181 BP 715 EP 722 DI 10.1016/S0168-583X(01)00541-9 PG 8 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 470RR UT WOS:000170885400124 ER PT J AU Govindaraj, R Gopinathan, KP Viswanathan, B AF Govindaraj, R Gopinathan, KP Viswanathan, B TI Hf impurity and defect interactions in helium-implanted NiHf SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article ID POSITRON-ANNIHILATION; ANGULAR-CORRELATIONS; METALS; SPECTROSCOPY; GROWTH; NICKEL; TDPAC; HE AB TDPAC measurements on the reference and untreated sample indicate a loss in anisotropy which is attributed mainly to the association of probe atoms with defects produced by (n, gamma) reactions with isotopes of Ni and experiencing combined magnetic and quadrupole interactions of comparable strengths. Evolution of defect free and substitutional fraction of probe atoms experiencing Larmor frequency characteristic of Ni matrix has been studied as a function of isochronal annealing temperature in helium free alpha -irradiated and homogeneously helium-implanted samples. No defect associated Larmor precession frequency and/or quadrupole frequency could be deduced in these uncorrelated damage studies. Comparison of recovery stages in alpha -irradiated and helium-implanted samples indicates the binding of helium associated defects by Hf impurities. Segregation of Hf atoms is observed in the helium free alpha -irradiated sample for annealing treatment at 973 K, while no such effect is observed in the helium-implanted sample for isochronal annealing treatments up to 1273 K. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Indira Gandhi Ctr Atom Res, Div Mat Sci, Kalpakkam 603102, Tamil Nadu, India. Brookhaven Natl Lab, Publ & Environm Hlth Lab, New York, NY 11788 USA. RP Govindaraj, R (reprint author), Indira Gandhi Ctr Atom Res, Div Mat Sci, Kalpakkam 603102, Tamil Nadu, India. NR 30 TC 2 Z9 3 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 JUL PY 2001 VL 179 IS 2 BP 200 EP 208 DI 10.1016/S0168-583X(01)00474-8 PG 9 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 445BK UT WOS:000169438100006 ER PT J AU Fowler, JS Volkow, ND Wang, GJ Gatley, SJ Logan, J AF Fowler, JS Volkow, ND Wang, GJ Gatley, SJ Logan, J TI [(11)]Cocaine: PET studies of cocaine pharmacokinetics, dopamine transporter availability and dopamine transporter occupancy SO NUCLEAR MEDICINE AND BIOLOGY LA English DT Article; Proceedings Paper CT Receptor 2000 Symposium CY APR, 2000 CL LA JOLLA, CALIFORNIA DE cocaine; carbon-11; [C-11]cocaine; dopamine transporter; Logan plot; PET ID POSITRON EMISSION TOMOGRAPHY; I-123 BETA-CIT; HUMAN BRAIN; BINDING-SITES; C-11 COCAINE; SYNAPTIC DOPAMINE; BABOON BRAIN; IN-VIVO; NEURONAL FUNCTION; DRUG-ABUSE AB Cocaine was initially labeled with carbon-11 in order to track the distribution and pharmacokinetics of this powerful stimulant and drug of abuse in the human brain and body. It was soon discovered that [C-11]cocaine was not only useful for measuring cocaine pharmacokinetics and its relationship to behavior but that it is also a sensitive radiotracer for dopamine transporter (DAT) availability. Measures of DAT availability were facilitated by the development of a graphical analysis method (Logan Plot) for reversible systems which streamlined kinetic analysis. This expanded the applications of [C-11]cocaine to studies of DAT availability in the human brain and allowed the first comparative measures of the degree of DAT occupancy by cocaine and another stimulant drug methylphenidate. This article will summarize preclinical and clinical research with [C-11]cocaine. (C) 2001 Elsevier Science Inc. All rights reserved. C1 Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. Brookhaven Natl Lab, Dept Med, Upton, NY 11973 USA. RP Fowler, JS (reprint author), Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. FU NIDA NIH HHS [DA-06891] NR 70 TC 38 Z9 39 U1 2 U2 4 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0969-8051 J9 NUCL MED BIOL JI Nucl. Med. Biol. PD JUL PY 2001 VL 28 IS 5 BP 561 EP 572 DI 10.1016/S0969-8051(01)00211-6 PG 12 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 447AT UT WOS:000169546900011 PM 11516700 ER PT J AU Wareing, TA McGhee, JM Morel, JE Pautz, SD AF Wareing, TA McGhee, JM Morel, JE Pautz, SD TI Discontinuous finite element S-N methods on three-dimensional unstructured grids SO NUCLEAR SCIENCE AND ENGINEERING LA English DT Article ID DIFFUSION-SYNTHETIC ACCELERATION; DISCRETE-ORDINATES EQUATIONS AB Discontinuous finite element methods for the SN equations on three-dimensional unstructured tetrahedral and hexahedral meshes are presented Solution techniques including source iteration and diffusion-synthetic acceleration are described. Numerical results are presented that demonstrate the accuracy and efficiency of these methods. C1 Univ Calif Los Alamos Natl Lab, Transport Methods Grp, XTM, Los Alamos, NM 87545 USA. RP Wareing, TA (reprint author), Univ Calif Los Alamos Natl Lab, Transport Methods Grp, XTM, POB 1663,MS D409, Los Alamos, NM 87545 USA. NR 10 TC 81 Z9 88 U1 1 U2 5 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0029-5639 J9 NUCL SCI ENG JI Nucl. Sci. Eng. PD JUL PY 2001 VL 138 IS 3 BP 256 EP 268 PG 13 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 442DB UT WOS:000169269000003 ER PT J AU Wang, X Tsoukalas, LH Wei, TYC Reifman, J AF Wang, X Tsoukalas, LH Wei, TYC Reifman, J TI An innovative fuzzy-logic-based methodology for trend identification SO NUCLEAR TECHNOLOGY LA English DT Article DE fuzzy logic; signal trend; transient identification ID TRANSIENT DIAGNOSTIC SYSTEM; PRODIAG AB A new fuzzy-logic-based methodology for on-line signal trend identification is introduced The methodology may be used for detecting the onset of nuclear power plant (NPP) transients at the earliest possible time and could be of great benefit to diagnostic, maintenance, and performance-monitoring programs. Although signal trend identification is complicated by the presence of noise, fuzzy methods can help capture important features of on-line signals, integrate the information included in these features, and classify incoming NPP signals into increasing, decreasing, and steady-state trend categories. A computer program named PROTREN is developed and tested for the purpose of verifying this methodology using NPP and simulation data. The results indicate that the new fuzzy-logic-based methodology is capable of detecting transients accurately, it identifies trends reliably and does not misinterpret a steady-state signal as a transient one. C1 Purdue Univ, Sch Nucl Engn, W Lafayette, IN 47907 USA. Argonne Natl Lab, Reactor Anal & Engn Div, Argonne, IL 60439 USA. RP Wang, X (reprint author), Purdue Univ, Sch Nucl Engn, W Lafayette, IN 47907 USA. NR 9 TC 6 Z9 6 U1 0 U2 1 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0029-5450 J9 NUCL TECHNOL JI Nucl. Technol. PD JUL PY 2001 VL 135 IS 1 BP 67 EP 84 PG 18 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 445LJ UT WOS:000169458700005 ER PT J AU King, JS Pregitzer, KS Zak, DR Sober, J Isebrands, JG Dickson, RE Hendrey, GR Karnosky, DF AF King, JS Pregitzer, KS Zak, DR Sober, J Isebrands, JG Dickson, RE Hendrey, GR Karnosky, DF TI Fine-root biomass and fluxes of soil carbon in young stands of paper birch and trembling aspen as affected by elevated atmospheric Co-2 and tropospheric O-3 SO OECOLOGIA LA English DT Article DE northern forests; global change; carbon sequestration; soil respiration; dissolved organic carbon; soil pCO(2) ID DISSOLVED ORGANIC NUTRIENTS; NET PRIMARY PRODUCTION; CO2 ENRICHMENT; PONDEROSA PINE; FOREST ECOSYSTEMS; HUMIC SUBSTANCES; DECIDUOUS FOREST; N AVAILABILITY; STREAM WATER; SCOTS PINE AB Rising atmospheric CO2 may stimulate future forest productivity, possibly increasing carbon storage in terrestrial ecosystems, but how tropospheric ozone will modify this response is unknown. Because of the importance of fine roots to the belowground C cycle, we monitored fine-root biomass and associated C fluxes in regenerating stands of trembling aspen, and mixed stands of trembling aspen and paper birch at FACTS-II, the Aspen FACE project in Rhinelander, Wisconsin. Free-air CO2 enrichment (FACE) was used to elevate concentrations of CO2 (average enrichment concentration 535 mul l(-1)) and O-3 (53 nl l(-1)) in developing forest stands in 1998 and 1999. Soil respiration, soil pCO(2), and dissolved organic carbon in soil solution (DOC) were monitored biweekly. Soil respiration was measured with a portable infrared gas analyzer. Soil pCO(2) and DOC samples were collected from soil gas wells and tension lysimeters, respectively. at depths of 15, 30, and 125 cm. Fine-root biomass averaged 263 g m(-2) in control plots and increased 96% under elevated CO2. The increased root biomass was accompanied by a 39% increase in soil respiration and a 27% increase in soil pCO(2). Both soil respiration and pCO(2) exhibited a strong seasonal signal, which was positively correlated with soil temperature. DOC concentrations in soil solution averaged similar to 12 mg l(-1) in surface horizons, declined with depth, and were little affected by the treatments. A simplified belowground C budget for the site indicated that native soil organic matter still dominated the system, and that soil respiration was by far the largest flux. Ozone decreased the above responses to elevated CO2, but effects were rarely statistically significant. We conclude that regenerating stands of northern hardwoods have the potential for substantially greater C input to soil due to greater fine-root production under elevated CO2 Greater fine-root biomass will be accompanied by greater soil C efflux as soil respiration, but leaching losses of C will probably be unaffected. C1 Michigan Technol Univ, Sch Forestry & Wood Prod, Houghton, MI 49931 USA. USPA Forest Serv, N Cent Res Stn, Houghton, MI 49931 USA. Univ Michigan, Sch Nat Resources & Environm, Ann Arbor, MI 48109 USA. USDA, Forest Serv, N Cent Res Stn, Rhinelander, WI 54501 USA. US DOE, Brookhaven Natl Lab, Dept Appl Sci, Div Environm Biol & Instrumentat, Upton, NY 11973 USA. RP King, JS (reprint author), Michigan Technol Univ, Sch Forestry & Wood Prod, Houghton, MI 49931 USA. RI Zak, Donald/C-6004-2012 NR 90 TC 106 Z9 122 U1 2 U2 25 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0029-8549 J9 OECOLOGIA JI Oecologia PD JUL PY 2001 VL 128 IS 2 BP 237 EP 250 PG 14 WC Ecology SC Environmental Sciences & Ecology GA 461YY UT WOS:000170392500011 ER PT J AU Driessen, BJ Sadegh, N AF Driessen, BJ Sadegh, N TI On the discontinuity of the costates for optimal control problems with Coulomb friction SO OPTIMAL CONTROL APPLICATIONS & METHODS LA English DT Article DE Coulomb friction; minimum time; optimal control; discontinuous costates; switching functions AB This work points out that the costates are actually discontinuous functions of time for optimal control problems with Coulomb friction. In particular these discontinuities occur at the time points where the velocity of the system changes sign. To our knowledge, this has not been noted before. This phenomenon is demonstrated on a mininium-titne problem with Coulomb friction and the consistency of discontinuous costates and switching functions with respect to the input switches is shown. Copyright (C) 2001 John Wiley & Sons, Ltd. C1 Sandia Natl Labs, Struct Dynam Dept, Albuquerque, NM 87185 USA. Georgia Inst Technol, Dept Mech Engn, Atlanta, GA 30332 USA. RP Driessen, BJ (reprint author), Sandia Natl Labs, Struct Dynam Dept, POB 5800,MS 0847, Albuquerque, NM 87185 USA. NR 2 TC 1 Z9 1 U1 0 U2 1 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 0143-2087 J9 OPTIM CONTR APPL MET JI Optim. Control Appl. Methods PD JUL-AUG PY 2001 VL 22 IS 4 BP 197 EP 200 DI 10.1002/oca.691 PG 4 WC Automation & Control Systems; Operations Research & Management Science; Mathematics, Applied SC Automation & Control Systems; Operations Research & Management Science; Mathematics GA 500QV UT WOS:000172639000002 ER PT J AU Newell, RL Ruiter, D Strenge, D AF Newell, RL Ruiter, D Strenge, D TI Adult caddisfly (Trichoptera) phenology in two cold-desert endorheic spring-streams in Washington State SO PAN-PACIFIC ENTOMOLOGIST LA English DT Article DE Insecta; Trichoptera; Caddisflies; phenology; Washington; Springs AB The species diversity and phenology of adult caddisflies was studied for two springs in the cold desert physiographic province of Eastern Washington State. During 1998 and 1999. adult caddisflies were collected using two light trapping methods: active collection using a mercury vapor light and passive collection using an ultraviolet light (UV). This study revealed a suprisingly diverse adult caddisfly fauna comprising eight families. 18 genera, and 36 species. with nine of the species collected being new distribution records of the State of Washington. Two species revealed significant range extensions with the closest records being from Utah. C1 Washington State Univ Tri Cities, Dept Biol Sci, Richland, WA 99352 USA. Pacific NW Natl Lab, Richland, WA 99352 USA. RP Newell, RL (reprint author), Washington State Univ Tri Cities, Dept Biol Sci, Richland, WA 99352 USA. NR 17 TC 3 Z9 3 U1 1 U2 1 PU PACIFIC COAST ENTOMOL SOC PI SAN FRANCISCO PA CALIFORNIA ACAD OF SCIENCES GOLDEN GATE PARK, SAN FRANCISCO, CA 94118 USA SN 0031-0603 J9 PAN-PAC ENTOMOL JI Pan-Pacific Entomol. PD JUL PY 2001 VL 77 IS 3 BP 190 EP 195 PG 6 WC Entomology SC Entomology GA 453VH UT WOS:000169936800006 ER PT J AU Yoo, BS Das, CR AF Yoo, BS Das, CR TI Efficient processor management schemes for mesh-connected multicomputers SO PARALLEL COMPUTING LA English DT Article DE first fit; limit allocation; multiprogramming; performance study; resource management; smallest job first ID HYPERCUBE COMPUTERS; ALLOCATION AB This paper investigates various processor management techniques for improving the performance of mesh-connected multicomputers. Unlike almost all prior work where the focus was on improving the submesh recognition ability of the processor allocation algorithms, this research examines other alternatives to improve system performance beyond what is achievable with usually assumed first come first served (FCFS) scheduling and any allocation. First, we use the smallest job first (SJF) policy to improve the spatial parallelism in a mesh. Next. we introduce a generic processor management scheme called multitasking and multiprogramming (M(2)). Then, an M(2) policy for mesh-connected multicomputers called virtual mesh (VM) is proposed and analyzed. The proposed VM scheme allows multiprogramming of jobs on several VMs. Finally, a novel approach called limit allocation is used for job allocation. With this scheme, a job (submesh) size is reduced if the job cannot be allocated. The objective here is to reduce the job waiting time and hence improve the overall performance. While all of the three approaches are viable alternatives to reduce the average job response time under various workloads, the VM and the limit allocation techniques are especially attractive for providing some additional features. The VM scheme brings in the concept of time-sharing execution for better efficiency and limit allocation shows how job size restriction can be beneficial for performance and fault-tolerance in a mesh topology. Moreover, the limit allocation scheme using even the simplest allocation policy can outperform any other approach. (C) 2001 Published by Elsevier Science B.V. C1 Lawrence Livermore Natl Lab, Ctr Appl Sci Comp, Livermore, CA 94551 USA. Penn State Univ, Dept Comp Sci & Engn, University Pk, PA 16802 USA. RP Yoo, BS (reprint author), Lawrence Livermore Natl Lab, Ctr Appl Sci Comp, Livermore, CA 94551 USA. EM ayoo@llnl.gov NR 35 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-8191 J9 PARALLEL COMPUT JI Parallel Comput. PD JUL PY 2001 VL 27 IS 8 BP 1057 EP 1078 DI 10.1016/S0167-8191(01)00078-3 PG 22 WC Computer Science, Theory & Methods SC Computer Science GA 437UN UT WOS:000169012100005 ER PT J AU Field, RD Thoma, DJ Dunn, PS Brown, DW Cady, CM AF Field, RD Thoma, DJ Dunn, PS Brown, DW Cady, CM TI Martensitic structures and deformation twinning in the U-Nb shape-memory alloys SO PHILOSOPHICAL MAGAZINE A-PHYSICS OF CONDENSED MATTER STRUCTURE DEFECTS AND MECHANICAL PROPERTIES LA English DT Article AB An investigation of the microstructures of four U-Nb alloys has been conducted. The nominal Nb contents are 5, 9, 13 and 18 at .% (approximately 2, 4, 5.5 and 8 wt%). The self-accommodating twin structures have been characterized and considered in terms of the lattice parameters of the martensite phases as well as the tetragonal distortion associated with the previously proposed intermediate gamma (0) phase. In addition, active deformation twinning systems during deformation of the U-13 at .% NB shape-memory alloy have been identified and are discussed with respect to the alpha " monoclinic distortion and ease of propagation in the microstructure. C1 Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. RP Field, RD (reprint author), Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Mail Stop G770, Los Alamos, NM 87545 USA. NR 40 TC 36 Z9 37 U1 2 U2 14 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 JUL PY 2001 VL 81 IS 7 BP 1691 EP 1724 PG 34 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Physics, Applied; Physics, Condensed Matter SC Materials Science; Metallurgy & Metallurgical Engineering; Physics GA 455DH UT WOS:000170011900003 ER PT J AU Roundy, D Krenn, CR Cohen, ML Morris, JW AF Roundy, D Krenn, CR Cohen, ML Morris, JW TI The ideal strength of tungsten SO PHILOSOPHICAL MAGAZINE A-PHYSICS OF CONDENSED MATTER STRUCTURE DEFECTS AND MECHANICAL PROPERTIES LA English DT Article ID FIRST-PRINCIPLES THEORY; CUBIC METALS; DEFORMATION; CRYSTALS; ALUMINUM; STRESS AB Using pseudopotential density functional theory within the local-density approximation, we calculate the ideal shear strengths of W for slip on {110}, {112} and {123} planes allowing for complete structural relaxation orthogonal to the applied shear. The strengths in the weak direction on all planes are found to very nearly equal (about 18 GPa, or 11% of the shear modulus G). Moreover, the shear instability occurs at approximately the same applied shear strain (17-18%). This unusual isotropy is explained in terms of the atomic configuration of high-energy saddle points reached during shear. Analysis of these saddle points may also offer a simple explanation for the prevalence of the pencil glide of dislocation on planes containing a < 111 > direction in bcc metals. Finally, we calculate the ideal cleavage strength of W on {100} and compare our calculated ideal shear and cleavage strengths with experimental nanoindentation and whisker measurements. All these results can be rather simply understood using a Frenkel-Orowan crystallographic mode. C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Mat Sci & Mineral Engn, Berkeley, CA 94720 USA. RP Morris, JW (reprint author), Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. NR 40 TC 166 Z9 168 U1 3 U2 40 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 JUL PY 2001 VL 81 IS 7 BP 1725 EP 1747 PG 23 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Physics, Applied; Physics, Condensed Matter SC Materials Science; Metallurgy & Metallurgical Engineering; Physics GA 455DH UT WOS:000170011900004 ER PT J AU McQueeney, RJ Manley, ME Osborn, R Fultz, B Kwei, GH Bogdanoff, PD AF McQueeney, RJ Manley, ME Osborn, R Fultz, B Kwei, GH Bogdanoff, PD TI Unexpected similarity of the dynamic magnetic susceptibilities of gamma-cerium and beta-cerium SO PHILOSOPHICAL MAGAZINE B-PHYSICS OF CONDENSED MATTER STATISTICAL MECHANICS ELECTRONIC OPTICAL AND MAGNETIC PROPERTIES LA English DT Article ID VALENCE ALLOY CE1-XTHX; CRYSTAL-FIELD; NEUTRON-SCATTERING; STATE PROPERTIES; SPIN DYNAMICS; EXCITATIONS; CE AB Inelastic magnetic neutron scattering spectra were measured on polycrystalline beta -Ce, gamma -Ce and samples containing both phases. For fee gamma -Ce, a broad magnetic quasielastic response is observed with a crystal-field excitation at 16.7 meV. For dhcp beta -Ce, a similar quasielastic response and a series of crystal-field excitations originating on both the cubic and the hexagonal site symmetries are expected. However, only the cubic site crystal-field excitation and broad quasielastic response are observed and, surprisingly, the magnetic spectrum of beta -Ce is nearly identical with that of the gamma phase. Such observations are entirely unexpected within a simple crystal-field model and probably arise from strong hybridization of the f states with the conduction band. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. CALTECH, Div Engn & Appl Sci, Pasadena, CA 91125 USA. Argonne Natl Lab, Argonne, IL 60439 USA. RP McQueeney, RJ (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. RI Osborn, Raymond/E-8676-2011; Manley, Michael/N-4334-2015; McQueeney, Robert/A-2864-2016 OI Osborn, Raymond/0000-0001-9565-3140; McQueeney, Robert/0000-0003-0718-5602 NR 28 TC 4 Z9 4 U1 0 U2 2 PU TAYLOR & FRANCIS LTD PI LONDON PA 11 NEW FETTER LANE, LONDON EC4P 4EE, ENGLAND SN 0141-8637 J9 PHILOS MAG B JI Philos. Mag. B-Phys. Condens. Matter Stat. Mech. Electron. Opt. Magn. Prop. PD JUL PY 2001 VL 81 IS 7 BP 675 EP 687 DI 10.1080/13642810108205770 PG 13 WC Materials Science, Multidisciplinary; Mechanics; Physics, Applied; Physics, Condensed Matter SC Materials Science; Mechanics; Physics GA 455NA UT WOS:000170031900002 ER PT J AU Chang, SC Shrock, R AF Chang, SC Shrock, R TI Structural properties of Potts model partition functions and chromatic polynomials for lattice strips SO PHYSICA A-STATISTICAL MECHANICS AND ITS APPLICATIONS LA English DT Article ID GROUND-STATE ENTROPY; NONCOMPACT W BOUNDARIES; DIRECTED-SITE ANIMALS; SQUARE LATTICE; 2-DIMENSIONAL LATTICES; ASYMPTOTIC LIMITS; SPANNING-TREES; PHASE-TRANSITIONS; MOTZKIN NUMBERS; 2 DIMENSIONS AB The q-state Potts model partition function (equivalent to the Tutte polynomial) for a lattice strip of fixed width L-y and arbitrary length L-x has the form Z(G, q, v) = Sigma (NZ,j)(j=1) c(Z,G,j)(lambda (Z,G,j))(Lx), where L; is a temperature-dependent variable. The special case of the zero-temperature antiferromagnet (v = -1) is the chromatic polynomial P(G, q). Using coloring and transfer matrix methods, we give general formulas for C-X,C-G = Sigma (NX,j)(j=1) c(X,G,j) for X = Z,P on cyclic and Mobius strip graphs of the square and triangular lattice. Combining these with a general expression for the (unique) coefficient c(Z,G,j) of degree d in q: c((d)) = U-2d(rootq/2), where U-n(x) is the Chebyshev polynomial of the second kind, we determine the number of lambda (Z,G,j)'s with coefficient c((d)) in Z(G,q,v) for these cyclic strips of width L-y to be n(Z)(L-y,d)=(2d + 1)(L-y + d + 1)(-1) ((2Lx)(Ly-d)) for 0 less than or equal to d less than or equal to L-y and zero otherwise, For both cyclic and Mobius strips of these lattices, the total number of distinct eigenvalues lambda (Z,G,j) is calculated to be N-Z,N-L,N-lambda=((2Lx)(Ly)). Results are also presented for the analogous numbers n(P)(L-y, d) and N(P,Ly,)lambda for P(G,q). We find that n(P)(L-y, 0)=n(P)(L-y- 1,1)=MLx-1 (Motzkin number), n(Z)(L-y,0)= C-Lx (the Catalan number), and give an exact expression for N-P,N-Ly,N-lambda. Our results for N-Z,N-Ly,N-lambda and N-P,N-Ly,N-lambda apply for both the cyclic and Mobius strips of both the square and triangular lattices; we also point out the interesting relations N-Z,N-Ly,N-lambda = 2N(DA,tri.Ly) and N-P,N-Ly,N-lambda = 2N(DA,sq,Ly,) where N-DA,N-A,N-n denotes the number of directed lattice animals on the lattice Lambda. We find the asymptotic growths N-Z,N-Ly,N-lambda similar to L-y(-1.2) 4(Ly) and N-P,N-Ly,N-lambda similar to L(y)(-1.2)3(Ly) as L-y --> infinity. Some general geometric identities for Potts model partition functions are also presented. 0 2001 Published by Elsevier Science B.V. C1 SUNY Stony Brook, CN Yang Inst Theoret Phys, Stony Brook, NY 11794 USA. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP SUNY Stony Brook, CN Yang Inst Theoret Phys, Stony Brook, NY 11794 USA. EM shu-chiuan.chang@sunysb.edu; robert.shrock@sunysb.edu NR 91 TC 42 Z9 42 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0378-4371 EI 1873-2119 J9 PHYSICA A JI Physica A PD JUL 1 PY 2001 VL 296 IS 1-2 BP 131 EP 182 DI 10.1016/S0378-4371(01)00150-9 PG 52 WC Physics, Multidisciplinary SC Physics GA 447VY UT WOS:000169594200011 ER PT J AU Mezei, F Russina, M AF Mezei, F Russina, M TI New opportunities in quasi elastic neutron scattering spectroscopy SO PHYSICA B LA English DT Article; Proceedings Paper CT 5th International Conference on Quasi-Elastic Neutron Scattering (QENS 2000) CY AUG 31-SEP 01, 2000 CL EDINBURGH, SCOTLAND SP Neutron Round Tabl, Royal Soc Edinburgh, Heriot Watt Univ, ISIS Fac, Rutherford Appleton Lab DE quasi-elastic neutron scattering; instrumentation; backscattering AB The high energy resolution usually required in quasi elastic neutron scattering (QENS) spectroscopy is commonly achieved by the use of cold neutrons. This is one of the important research areas where the majority of current work is done on instruments on continuous reactor sources. One particular reason for this is the capability of continuous source time-of-flight spectrometers to use instrumental parameters optimally adapted for best data collection efficiency in each experiment. These parameters include the pulse repetition rate and the length of the pulses to achieve optimal balance between resolution and intensity. In addition, the disc chopper systems used provide perfect symmetrical line shapes with no tails and low background. Recent development of a set of novel techniques enhance the efficiency of cold neutron spectroscopy on existing and future spallation sources in a dramatic fashion. These techniques involve the use of extended pulse length, high intensity coupled moderators, disc chopper systems and advanced neutron optical beam delivery, and they will enable Lujan center at Los Alamos to surpass the best existing reactor instruments in time-of-flight QENS work by more than on order of magnitude in terms of beam flux on the sample. Other applications of the same techniques will allow us to combine advantages of backscattering spectroscopy on continuous and pulsed sources in order to deliver mu eV resolution in a very broad energy transfer range. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Hahn Meitner Inst Kernforsch Berlin GmbH, Berline Neutron Scattering Ctr, D-14109 Berlin, Germany. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Mezei, F (reprint author), Hahn Meitner Inst Kernforsch Berlin GmbH, Berline Neutron Scattering Ctr, Glienicker Str 100,Postfach 390128, D-14109 Berlin, Germany. RI Russina, Margarita/E-9886-2016 OI Russina, Margarita/0000-0003-2067-606X NR 4 TC 2 Z9 2 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 JUL PY 2001 VL 301 IS 1-2 BP 94 EP 98 DI 10.1016/S0921-4526(01)00517-8 PG 5 WC Physics, Condensed Matter SC Physics GA 447GF UT WOS:000169563000015 ER PT J AU Peeters, FM Riva, C Varga, K AF Peeters, FM Riva, C Varga, K TI Trions in quantum wells SO PHYSICA B-CONDENSED MATTER LA English DT Article DE trions; quantum wells ID NEGATIVELY CHARGED EXCITONS; 2-DIMENSIONAL ELECTRON-GAS; HIGH MAGNETIC-FIELDS; CYCLOTRON-RESONANCE; OPTICAL-ABSORPTION; D-CENTERS; PHOTOLUMINESCENCE; COMPLEXES; SEMICONDUCTORS; ENERGY AB An overview is given of our investigation of the energy levels and of the correlation functions of the negatively and positively charged excitons (also called trions) in quantum wells in the presence of a perpendicular magnetic field, A detailed comparison is made with available experimental data in III-V and II-VI semiconductor quantum wells. (C) 2001 Elsevier Science B.V. All rights reserved. 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, Univ Pl 1, B-2610 Antwerp, Belgium. EM peeters@uia.ua.ac.be RI Varga, Kalman/A-7102-2013; CMT, UAntwerpen Group/A-5523-2016 NR 70 TC 26 Z9 26 U1 0 U2 2 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 JUL PY 2001 VL 300 IS 1-4 BP 139 EP 155 DI 10.1016/S0921-4526(01)00577-4 PG 17 WC Physics, Condensed Matter SC Physics GA 470BF UT WOS:000170850000011 ER PT J AU Okram, GS Terakura, C Uji, S Aoki, H Xu, M Hinks, DG AF Okram, GS Terakura, C Uji, S Aoki, H Xu, M Hinks, DG TI Irreversibility line and lock-in transition in Tl2Ba2CuO6 single crystals SO PHYSICA C LA English DT Article ID HIGH-TEMPERATURE SUPERCONDUCTORS; HIGH-TC SUPERCONDUCTORS; GIANT FLUX-CREEP; LAYERED SUPERCONDUCTOR; MIXED STATE; VORTICES; MODEL; DISSIPATION; FIELD; FILMS AB We investigated the irreversibility lines (H-irr) and their correlation with lock-in transition on over-doped Tl2Ba2CuO2 single crystals using magneto-resistive measurement results. The lock-in transition is observed only above the irreversibility line H-irr perpendicular to(t) for magnetic field H-parallel to c-axis, where t = T/T-c is the reduced temperature. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Natl Phys Lab, Cryogen & Superconduct Div, New Delhi 110012, India. Natl Res Inst Met, Tsukuba, Ibaraki 305, Japan. Tohoku Univ, Ctr Low Temp Sci, Sendai, Miyagi 98077, Japan. Univ Chicago, James Franck Inst, Chicago, IL 60637 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Okram, GS (reprint author), Natl Phys Lab, Cryogen & Superconduct Div, Dr KS Krishnan Rd, New Delhi 110012, India. RI Terakura, Chieko/A-5959-2009 NR 23 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD JUL 1 PY 2001 VL 356 IS 1-2 BP 115 EP 121 DI 10.1016/S0921-4534(01)00129-0 PG 7 WC Physics, Applied SC Physics GA 446WL UT WOS:000169537100013 ER PT J AU Montalenti, F Voter, AF AF Montalenti, F Voter, AF TI Applying accelerated molecular dynamics to crystal growth SO PHYSICA STATUS SOLIDI B-BASIC RESEARCH LA English DT Article; Proceedings Paper CT 2nd Motorola Workshop on Computational Materials and Electronics CY NOV 09-10, 2000 CL TEMPE, ARIZONA ID INFREQUENT EVENTS; LAYER GROWTH; DIFFUSION; HYPERDYNAMICS; MECHANISMS; SIMULATION; CLUSTERS; SURFACES; ADATOM AB We discuss how recent accelerated molecular dynamics techniques can be applied to crystal growth studies. Focusing our attention on the temperature accelerated dynamics (TAD) method, we show that at low temperatures the accessible time scale can be several orders of magnitude greater than with ordinary molecular dynamics. This allows us to match experimental deposition rates, as shown by preliminary results for the Cu/Cu(100) system. C1 Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Montalenti, F (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, POB 1663, Los Alamos, NM 87545 USA. RI Montalenti, Francesco/A-7738-2010 OI Montalenti, Francesco/0000-0001-7854-8269 NR 24 TC 11 Z9 12 U1 0 U2 5 PU WILEY-V C H VERLAG GMBH PI BERLIN PA PO BOX 10 11 61, D-69451 BERLIN, GERMANY SN 0370-1972 J9 PHYS STATUS SOLIDI B JI Phys. Status Solidi B-Basic Res. PD JUL PY 2001 VL 226 IS 1 BP 21 EP 27 DI 10.1002/1521-3951(200107)226:1<21::AID-PSSB21>3.0.CO;2-Q PG 7 WC Physics, Condensed Matter SC Physics GA 455QG UT WOS:000170037800008 ER PT J AU Dixon, DA Matsuzawa, NN Ishitani, A Uda, T AF Dixon, DA Matsuzawa, NN Ishitani, A Uda, T TI Time-dependent density functional theory calculations of photoabsorption of fluorinated cyclic molecules in the vacuum ultraviolet region SO PHYSICA STATUS SOLIDI B-BASIC SOLID STATE PHYSICS LA English DT Article; Proceedings Paper CT 2nd Motorola Workshop on Computational Materials and Electronics CY NOV 09-10, 2000 CL TEMPE, AZ ID KOHN-SHAM ORBITALS; EXCITATION-ENERGIES; DYNAMIC POLARIZABILITIES; RESPONSE THEORY; WAVE-FUNCTIONS; BASIS-SET; APPROXIMATION; SYSTEMS; IMPLEMENTATION; EIGENVALUES AB Time-dependent density functional theory (TD-DFT) calculations of the photoabsorption of molecules in the vacuum ultraviolet region have been performed in order to aid in the design of transparent materials for use as photoresists for F-2 lithography (157 nm). The method including an empirical equation for correcting the calculated transition energy is described. We have used the TD-DFT approach to predict the photoabsorption of substituted benzenes, and cycloalkanes including norbornane. The calculations show that norbornane is the best cycloalkane on which to start substitution studies. We report results on the mono-, di-, and tetra-fluorinated derivatives. The results show that the tetrafluoro-norbornanes have the lowest absorption in the 157 nm range for the molecules that we studied. C1 Pacific NW Natl Lab, William R Wiley Environm Mol Sci Lab, Richland, WA 99352 USA. NTT Corp, Atsugi R&D Ctr, Atsugi Res Ctr, Assoc Super Adv Elect Technol, Atsugi, Kanagawa 2430198, Japan. Natl Inst Adv Interdisciplinary Res, Angstrom Technol Partnership, JRCAT, Tsukuba, Ibaraki 3050046, Japan. RP Matsuzawa, NN (reprint author), Pacific NW Natl Lab, William R Wiley Environm Mol Sci Lab, MSIN K1-83,POB 999,902 Battele Blvd, Richland, WA 99352 USA. NR 39 TC 14 Z9 14 U1 0 U2 2 PU WILEY-V C H VERLAG GMBH PI WEINHEIM PA BOSCHSTRASSE 12, D-69469 WEINHEIM, GERMANY SN 0370-1972 EI 1521-3951 J9 PHYS STATUS SOLIDI B JI Phys. Status Solidi B-Basic Solid State Phys. PD JUL PY 2001 VL 226 IS 1 BP 69 EP 77 DI 10.1002/1521-3951(200107)226:1<69::AID-PSSB69>3.0.CO;2-7 PG 9 WC Physics, Condensed Matter SC Physics GA 455QG UT WOS:000170037800013 ER PT J AU Crocce, M Dalvit, DAR Mazzitelli, FD AF Crocce, M Dalvit, DAR Mazzitelli, FD TI Resonant photon creation in a three-dimensional oscillating cavity SO PHYSICAL REVIEW A LA English DT Article ID CASIMIR LIGHT; RENORMALIZATION-GROUP; MOVING MIRRORS; MU-M; RADIATION; BOUNDARY; GENERATION; MODES; FORCE; WALL AB We analyze the problem of photon creation inside a perfectly conducting, rectangular, three-dimensional cavity with one oscillating wall. For some particular values of the frequency of the oscillations the system is resonant. We solve the field equation using multiple scale analysis and show that the total number of photons inside the cavity grows exponentially in time. This is also the case for slightly off-resonance situations. Although the spectrum of a cavity is in general nonequidistant, we show that the modes of the electromagnetic field can be coupled, and that the rate of photon creation strongly depends on this coupling. We also analyze the thermal enhancement of the photon creation. C1 Univ Buenos Aires, Dipartimento Fis JJ Giambiagi, RA-1428 Buenos Aires, DF, Argentina. Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Crocce, M (reprint author), Univ Buenos Aires, Dipartimento Fis JJ Giambiagi, Ciudad Univ,Pabellon I, RA-1428 Buenos Aires, DF, Argentina. EM mcrocce@df.uba.ar; dalvit@lanl.gov; fmazzi@df.uba.ar NR 31 TC 74 Z9 74 U1 0 U2 1 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 JUL PY 2001 VL 64 IS 1 AR 013808 DI 10.1103/PhysRevA.64.013808 PG 10 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 449XA UT WOS:000169711400115 ER PT J AU Heifets, S AF Heifets, S TI Dynamics of the coherent state in a quantum amplifier SO PHYSICAL REVIEW A LA English DT Article AB Evolution of the density matrix in a quantum amplifier is described for initial conditions corresponding to superposition of the coherent states. The approach developed in the paper is also applicable for an arbitrary initial condition allowing the inverse Mellin transform. As such an example, we consider the evolution of the squeezed state. C1 Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Heifets, S (reprint author), Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. NR 2 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 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD JUL PY 2001 VL 64 IS 1 AR 013806 PG 4 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 449XA UT WOS:000169711400113 ER PT J AU Kim, YH Berardi, V Chekhova, MV Shih, YH AF Kim, YH Berardi, V Chekhova, MV Shih, YH TI Anticorrelation effect in femtosecond-pulse pumped type-II spontaneous parametric down-conversion SO PHYSICAL REVIEW A LA English DT Article ID 2-PHOTON ENTANGLEMENT; QUANTUM INTERFERENCE; 2 PHOTONS; INDISTINGUISHABILITY; PAIRS AB We report an experimental demonstration of an anticorrelation effect in femtosecond-pulse pumped type-II spontaneous parametric down-conversion. Our experimental data, which is different from that of Atature et al. [Phys. Rev. Lett. 83, 1323 (2000)], confirmed the shallow symmetric "dip" that is predicted theoretically by Keller and Rubin [Phys. Rev. A 56, 1534 (1997)] and Grice and Walmsley [Phys. Rev. A 56, 1627 (1997)]. We show in this paper that the asymmetric dip observed in the literature is an artifact, which is caused by the asymmetric optical elements introduced into the beam path after the down-conversion process. The "partial distinguishability" theory suggested by Atature et al. is therefore incorrect. C1 Univ Maryland Baltimore Cty, Dept Phys, Baltimore, MD 21250 USA. Univ Bari, Dipartimento Interateneo Fis, INFM, Bari, Italy. Moscow MV Lomonosov State Univ, Dept Phys, Moscow, Russia. RP Oak Ridge Natl Lab, Ctr Engn Sci Adv Res, Oak Ridge, TN 37830 USA. EM yokim@umbc.edu RI Kim, Yoonho/D-2591-2012; Berardi, Vincenzo/H-4550-2011; Chekhova, Maria/A-4659-2017 OI Chekhova, Maria/0000-0002-3399-2101 NR 18 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 2469-9926 EI 2469-9934 J9 PHYS REV A JI Phys. Rev. A PD JUL PY 2001 VL 64 IS 1 AR 011801 PG 4 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 449XA UT WOS:000169711400012 ER PT J AU Antonov, VN Harmon, BN Yaresko, AN AF Antonov, VN Harmon, BN Yaresko, AN TI Electronic structure and x-ray magnetic circular dichroism in Cu3Au-type transition metal platinum alloys SO PHYSICAL REVIEW B LA English DT Review ID CORE-LEVEL PHOTOEMISSION; GROUND-STATE MOMENTS; MAGNETOOPTICAL PROPERTIES; ABSORPTION-SPECTRA; SUM-RULES; ANGULAR-DEPENDENCE; SPIN; FE; POLARIZATION; 3D AB The electronic structure and x-ray magnetic circular dichroism (XMCD) in XPt3 (X = V, Cr, Mn, Fe, Co, Ni) and X3Pt (X= Fe, Co, Ni) compounds are investigated theoretically from first principles, using the fully relativistic Dirac LMTO band structure method. The electronic structure is obtained with the local spin-density approximation (LSDA). Theoretically calculated spin and orbital magnetic moments are found to be in good agreement with neutron and XMCD experimental data. An interpretation for systematic trends seen in the orbital and spin magnetic moments of the series XPt3 is presented by analyzing the calculated spin- and orbital-projected density of d states. The important role of hybridization between the 3d transition metal and Pt d states in the formation of the orbital magnetic moments at the Pt site is emphasized. The x-ray absorption spectra as well as the x-ray circular magnetic dichroism at the K, L-2,L-3, and M-2,M-3 edges for transition metal sites and L-2,L-3, M-2,M-3, M-4,M-5, N-2,N-3, N-4,N-5, N-6,N-7, and O-2,O-3 edges for Pt sites are calculated for all nine compounds. Good agreement between theory and the experiment is obtained. The XMCD sum rules are used to compute the spin and orbital magnetic moments and the results are compared to the direct calculations. C1 Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. Max Planck Inst Phys Complex Syst, D-01187 Dresden, Germany. Inst Met Phys, UA-03142 Kiev, Ukraine. RP Antonov, VN (reprint author), Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. NR 103 TC 13 Z9 13 U1 3 U2 12 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 JUL 1 PY 2001 VL 64 IS 2 AR 024402 DI 10.1103/PhysRevB.64.024402 PG 15 WC Physics, Condensed Matter SC Physics GA 452AV UT WOS:000169835700043 ER PT J AU Asta, MN Ozolins, V Hoyt, JJ van Schilfgaarde, M AF Asta, MN Ozolins, V Hoyt, JJ van Schilfgaarde, M TI Ab initio molecular-dynamics study of highly nonideal structural and thermodynamic properties of liquid Ni-Al alloys SO PHYSICAL REVIEW B LA English DT Article ID TOTAL-ENERGY CALCULATIONS; EARTHS CORE CONDITIONS; WAVE BASIS-SET; ELECTRON SYSTEMS; TRANSITION; SIMULATION; METALS; IRON; STATE AB Atomic and electronic structure, and diffusion coefficients in liquid Ni-Al alloys, have been calculated by ab initio molecular-dynamics simulations. The chemically short-range ordered structure of liquid Ni20Al80 measured by neutron scattering is well reproduced in these simulations. We calculate a significant electronic contribution (DeltaS(el)= - 0.4 k(B)/atom) to the formation entropy of NiAl at 1900 K, originating from a simultaneous narrowing and shifting of the Ni d band to higher binding energies accompanying alloying with Al. This value of DeltaS(el), combined with an estimate for the configurational entropy based on calculated radial distribution functions and a nonadditive hard-sphere model, accounts for the large negative excess entropy of mixing measured in liquid Ni-Al alloys. C1 Northwestern Univ, Dept Mat Sci & Engn, Evanston, IL 60208 USA. Sandia Natl Labs, Livermore, CA 94551 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Asta, MN (reprint author), Northwestern Univ, Dept Mat Sci & Engn, Evanston, IL 60208 USA. RI Ozolins, Vidvuds/D-4578-2009 NR 49 TC 21 Z9 21 U1 2 U2 8 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 JUL 1 PY 2001 VL 64 IS 2 AR 020201 DI 10.1103/PhysRevB.64.020201 PG 4 WC Physics, Condensed Matter SC Physics GA 452AV UT WOS:000169835700003 ER PT J AU Bao, W Pagliuso, PG Sarrao, JL Thompson, JD Fisk, Z Lynn, JW AF Bao, W Pagliuso, PG Sarrao, JL Thompson, JD Fisk, Z Lynn, JW TI Magnetic structure of heavy-fermion Ce2RhIn8 SO PHYSICAL REVIEW B LA English DT Article ID SUPERCONDUCTIVITY; CERHIN5; CEIN3 AB The magnetic structure of the heavy-fermion antiferromagnet Ce2RhIn8 is determined using neutron diffraction. It is a collinear antiferromagnet with a magnetic wave vector (1/2,1/2,0) and a staggered moment of 0.55(6)mu (B) per Ce at 1.6 K, tilted 38(2)degrees from the tetragonal c axis. In spite of its layered crystal structure, the phases for the magnetic moments are the same as those in the cubic parent antiferromagnet CeIn3. This suggests that the cubic CeIn3 building blocks have a stronger influence on magnetic correlations than intervening RhIn2 layers, which give the material its apparent two-dimensional lattice structure and renders CeRhIn5 an incommensurate antiferromagnet. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Natl Inst Stand & Technol, NIST Ctr Neutron Res, Gaithersburg, MD 20899 USA. RP Fisk, Z (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. RI Pagliuso, Pascoal/C-9169-2012; Bao, Wei/E-9988-2011 OI Bao, Wei/0000-0002-2105-461X NR 26 TC 51 Z9 51 U1 0 U2 10 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 JUL 1 PY 2001 VL 64 IS 2 AR 020401 DI 10.1103/PhysRevB.64.020401 PG 4 WC Physics, Condensed Matter SC Physics GA 452AV UT WOS:000169835700006 ER PT J AU Cao, WW Saxena, A Hatch, DM AF Cao, WW Saxena, A Hatch, DM TI Antiphase structures of an improper ferroelastic phase transition driven by an M-5(-) zone boundary phonon in RAg1-xInx SO PHYSICAL REVIEW B LA English DT Article ID INTERPHASE BOUNDARIES; CRYSTAL-STRUCTURES; TRANSFORMATION; PEROVSKITES; MODEL AB Rare-earth alloys RAg1-xInx (where R = La, Ce, and Pr) are improper ferroelastic materials with the CsCl structure. A weakly first-order phase transition occurs with the softening of a zone-edge M-5(-) mode that drives the material from a cubic phase to a tetragonal phase. Based on Ginzburg-Landau theory, we utilize the complete free-energy density, constructed from a six-dimensional primary order parameter (shuffle) that couples to strain, to study domain formation. The model allows the study of complex antiphase structures that appear in this cubic-to-tetragonal phase transition. With the help of numerical techniques, the order-parameter profiles across antiphase boundaries of different orientations and their temperature dependence are calculated. We find a single set of two coupled dimensionless governing equations, which are applicable to order-parameter profiles across all antiphase boundaries for this transition. C1 Penn State Univ, Mat Res Lab, University Pk, PA 16802 USA. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Brigham Young Univ, Dept Phys, Provo, UT 84602 USA. RP Cao, WW (reprint author), Penn State Univ, Mat Res Lab, University Pk, PA 16802 USA. EM cao@math.psu.edu; avadh@lanl.gov; hatchd@wigner.byu.edu RI Cao, Wenwu/F-6091-2012 OI Cao, Wenwu/0000-0002-2447-1486 NR 31 TC 7 Z9 7 U1 0 U2 2 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 JUL 1 PY 2001 VL 64 IS 2 AR 024106 DI 10.1103/PhysRevB.64.024106 PG 12 WC Physics, Condensed Matter SC Physics GA 452AV UT WOS:000169835700028 ER PT J AU Cox, DE Iglesias, T Moshopoulou, E Hirota, K Takahashi, K Endoh, Y AF Cox, DE Iglesias, T Moshopoulou, E Hirota, K Takahashi, K Endoh, Y TI Vertical boundary at x approximate to 0.11 in the structural phase diagram of the La1-xSrxMnO3 system (0.08 <= x <= 0.125) SO PHYSICAL REVIEW B LA English DT Article ID NEUTRON-DIFFRACTION; COLOSSAL-MAGNETORESISTANCE; MAGNETIC ORDER; CHARGE; TRANSITION; POLARON; LAMNO3; X-LESS-THAN-OR-EQUAL-TO-0.17; LA0.875SR0.125MNO3; RESISTIVITY AB The structural phase diagram of the La1-xSrxMnO3 system in the compositional range 0.08 less than or equal tox less than or equal to0.175 has been investigated by high-resolution synchrotron x-ray powder diffraction techniques between 20-600 K. Recent studies have reported that there is an unusual reentrant-type phase transition in this range involving an abrupt change in lattice parameters but no change in the crystal symmetry, which remains orthorhombic Pbnm. The transition to the reentrant phase is from a ferromagnetic metallic to a ferromagnetic insulating phase with some unusual properties. Our results demonstrate that for samples with x = 0.11-0.175 there exist two lower-symmetry structural regions having monoclinic and triclinic symmetry, respectively. There is a sharp first-order transition from the monoclinic to the triclinic phase coinciding with the transition to the ferromagnetic insulating phase, and an abrupt crossover from the orthorhombic Pbnm region with a near-vertical phase boundary just below x=0.11. The new phases indicate the presence of some novel type of orbital ordering unlike that found in LaMnO3. C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Tohoku Univ, Dept Phys, CREST, Sendai, Miyagi 9808578, Japan. RP Iglesias, T (reprint author), Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RI Hirota, Kazuma/C-6797-2008 NR 40 TC 42 Z9 43 U1 0 U2 3 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 JUL 1 PY 2001 VL 64 IS 2 AR 024431 DI 10.1103/PhysRevB.64.024431 PG 9 WC Physics, Condensed Matter SC Physics GA 452AV UT WOS:000169835700072 ER PT J AU Dimitrov, DA Roder, H Bishop, AR AF Dimitrov, DA Roder, H Bishop, AR TI Peak positions and shapes in neutron pair correlation functions from powders of highly anisotropic crystals SO PHYSICAL REVIEW B LA English DT Article ID DIFFRACTION AB The effect of the powder average on the peal; shapes and positions in neutron pair distribution functions of polycrystalline materials is examined. It is shown that for highly anisotropic crystals, the powder average leads to shifts in peak positions and to non-Gaussian peak shapes. The peak shifts can be as large as several percent of the lattice spacing. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 30 TC 7 Z9 7 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 JUL 1 PY 2001 VL 64 IS 1 AR 014303 DI 10.1103/PhysRevB.64.014303 PG 8 WC Physics, Condensed Matter SC Physics GA 449XF UT WOS:000169711900056 ER PT J AU Galambosi, S Soininen, JA Hamalainen, K Shirley, EL Kao, CC AF Galambosi, S Soininen, JA Hamalainen, K Shirley, EL Kao, CC TI Nonresonant inelastic x-ray scattering study of cubic boron nitride SO PHYSICAL REVIEW B LA English DT Article ID AB-INITIO CALCULATION; ELECTRON-HOLE INTERACTION; DYNAMIC STRUCTURE FACTOR; OPTICAL-ABSORPTION; RAMAN-SCATTERING; BAND-STRUCTURE; EXCITATIONS; SPECTRA; DIAMOND; STATE AB The dynamic structure factor of cubic boron nitride has been measured using nonresonant inelastic x-ray scattering. The experimental data are compared with the results of a recently developed ab initio calculation scheme, which takes into account the interaction between the excited electron and the hole. The agreement between the experiment and theory is good over an extended momentum transfer range, which emphasizes the importance of proper inclusion of the electron-hole interaction. The results are also compared with a reflectance measurement that represents the zero-momentum-transfer limit. The complementary nature of these different experimental methods is discussed in view of the ab initio calculations. C1 Univ Helsinki, Dept Phys, FIN-00014 Helsinki, Finland. Natl Inst Stand & Technol, Phys Lab, Opt Technol Div, Gaithersburg, MD 20899 USA. Brookhaven Natl Lab, Natl Synchrotron Light Source, Upton, NY 11973 USA. RP Galambosi, S (reprint author), Univ Helsinki, Dept Phys, POB 64, FIN-00014 Helsinki, Finland. RI Hamalainen, Keijo/A-3986-2010 OI Hamalainen, Keijo/0000-0002-9234-9810 NR 30 TC 11 Z9 11 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD JUL 1 PY 2001 VL 64 IS 2 AR 024102 DI 10.1103/PhysRevB.64.024102 PG 5 WC Physics, Condensed Matter SC Physics GA 452AV UT WOS:000169835700024 ER PT J AU Ignatov, AY Ali, N Khalid, S AF Ignatov, AY Ali, N Khalid, S TI MnK-edge XANES study of the La1-xCaxMnO3 colossal magnetoresistive manganites SO PHYSICAL REVIEW B LA English DT Article ID X-RAY-ABSORPTION; JAHN-TELLER DISTORTION; ELECTRONIC-STRUCTURE; DOUBLE-EXCHANGE; FINE-STRUCTURE; MANGANESE PEROVSKITES; K-EDGE; LA1-XSRXMNO3; TRANSITION; SPECTROSCOPY AB We report Mn K-edge x-ray absorption near edge structure (XANES) calculations of the La1-xCaxMnO3 manganites considering three pail. correlations, according to the three fundamental degrees of freedom governing their unusual electronic properties, namely, the electronic structure of the unoccupied states probed by the Mn K-edge profile versus (i) local atomic distortions; (ii) local magnetic ordering; and (iii) the charge-transfer nature of the Mn-O bonds. The calculations are accompanied by Mn K-edge XANES measurements in the temperature range 30-300 K. The main features of the absorption edge can be qualitatively reproduced in terms of single-electron multiple-scattering calculations for an 87-atom cluster. Lattice polaronic distortions in La0.7Ca0.3MnO3 are simulated assuming a strongly distorted orthorhombic structure above and an almost undistorted rhombohedral structure below T-c. The results roughly reproduce the energy "shift" across T-c observed experimentally. Mn K-edge spin-polarized XANES spectra of the x = 0, 0.3, and 1 samples are presented. An energy splitting between the majority- and minority-spin spectra of 0.5-1.1 eV contributes to the total XANES broadening below the Neel (Curie) temperature. A small feature B-3 Standing approximately 6 eV above the main absorption peak is beyond the scope of single-electron calculations; it is assigned to a shake-up transition. To illustrate, the calculated Mn K edge is obtained as the convolution product of the single-electron XANES and the spectrum of many-body excitations in the Mn-O electronic states upon the sudden switching on of the Mn Is core hole. We investigate the charge-transfer (CT) versus. Mott-Hubbard-type ground state using the U-c, Delta, and the T-dp parameters determined by previous Mn 2p x-ray photoemission spectroscopy measurements and find that LaMnO3 should be viewed as a CT-type insulator with a substantial O 2p component in the ground state. In light of these results the controversial issue of Mn valence states in the manganites is critically reexamined. We argue that the disproportionation may be understood as a mixture of the CT many-body electronic configurations coupled with spin and lattice degrees of freedom. C1 So Illinois Univ, Dept Phys, Carbondale, IL 62901 USA. Brookhaven Natl Lab, Natl Synchrotron Light Source, Upton, NY 11973 USA. RP Ignatov, AY (reprint author), So Illinois Univ, Dept Phys, Carbondale, IL 62901 USA. NR 57 TC 25 Z9 25 U1 1 U2 8 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 JUL 1 PY 2001 VL 64 IS 1 AR 014413 DI 10.1103/PhysRevB.64.014413 PG 16 WC Physics, Condensed Matter SC Physics GA 449XF UT WOS:000169711900071 ER PT J AU Jung, JK Baek, SH Borsa, F Bud'ko, SL Lapertot, G Canfield, PC AF Jung, JK Baek, SH Borsa, F Bud'ko, SL Lapertot, G Canfield, PC TI B-11 NMR and relaxation in the MgB2 superconductor SO PHYSICAL REVIEW B LA English DT Article ID FLUX AB B-11 NMR and nuclear-spin-lattice relaxation rate (NSLR) are reported at 7.2 T and 1.4 T in powder samples of the intermetallic compound MgB2 with the superconducting transition temperature in zero field T-c = 39.2 K. From the first-order quadrupole perturbed NMR spectrum a quadrupole coupling frequency of 835 +/- 5 kHz is obtained. The Knight shift is very small and it decreases to zero in the superconducting phase. The NSLR follows a linear law with T1T = 165 +/- 10 (sec K). The results in the normal phase indicate a negligible s character of thr wave function of the conduction electrons at the Fermi level. Below T-c the NSLR is strongly field dependent indicating the presence of an important contribution related to the density and the thermal motion of flux lines. No coherence peak is observed at the lower field investigated (1.4 T). C1 Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. Univ Pavia, Dipartimento Fis, I-27100 Pavia, Italy. Univ Pavia, INFM, I-27100 Pavia, Italy. RP Jung, JK (reprint author), Iowa State Univ, Ames Lab, Ames, IA 50011 USA. RI LAPERTOT, Gerard/B-3354-2008; Canfield, Paul/H-2698-2014; Baek, Seung-Ho/F-4733-2011 OI Baek, Seung-Ho/0000-0002-0059-8255 NR 18 TC 30 Z9 31 U1 0 U2 5 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD JUL 1 PY 2001 VL 64 IS 1 AR 012514 DI 10.1103/PhysRevB.64.012514 PG 4 WC Physics, Condensed Matter SC Physics GA 449XF UT WOS:000169711900039 ER PT J AU Kang, JS Han, H Lee, BW Olson, CG Han, SW Kim, KH Jeong, JI Park, JH Min, BI AF Kang, JS Han, H Lee, BW Olson, CG Han, SW Kim, KH Jeong, JI Park, JH Min, BI TI Electronic structure of the double-perovskite Ba2FeMoO6 using photoemission spectroscopy SO PHYSICAL REVIEW B LA English DT Article ID MAGNETIC-PROPERTIES; ROOM-TEMPERATURE; COLOSSAL-MAGNETORESISTANCE; SR2FEMOO6; TRANSITION; OXIDE; CA AB The electronic structure of Ba2FeMoO6 (BFMO) has been investigated by using photoemission spectroscopy (PES). By varying hv across the Mo 4d Cooper minimum, it is found that the states close to the Fermi level E-F are predominantly of the Mo t(2g) down arrow and Fe t(2g) down arrow character. The measured PES spectrum is compared to the calculated electronic structure obtained in the local spin-density approximation (LSDA) and LSDA+ U methods. The LSDA+ U calculation yields better agreement with experiment in the peak positions than does the LSDA calculation. The present study supports the double exchange mechanism for the half-metallic ferrimagnetism in BFMO. C1 Catholic Univ Korea, Dept Phys, Puchon 422743, South Korea. Hankuk Univ Foreign Studies, Dept Phys, Yongin 449791, Kyungki, South Korea. Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Gyeongsang Natl Univ, Dept Phys, Chinju 660701, South Korea. Res Inst Ind Sci & Technol, Pohang 790600, South Korea. Pohang Univ Sci & Technol, Dept Phys, Pohang 790784, South Korea. RP Catholic Univ Korea, Dept Phys, Puchon 422743, South Korea. NR 33 TC 35 Z9 35 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 JUL 1 PY 2001 VL 64 IS 2 AR 024429 DI 10.1103/PhysRevB.64.024429 PG 6 WC Physics, Condensed Matter SC Physics GA 452AV UT WOS:000169835700070 ER PT J AU Kim, YJ Birgeneau, RJ Chou, FC Greven, M Kastner, MA Lee, YS Wells, BO Aharony, A Entin-Wohlman, O Korenblit, IY Harris, AB Erwin, RW Shirane, G AF Kim, YJ Birgeneau, RJ Chou, FC Greven, M Kastner, MA Lee, YS Wells, BO Aharony, A Entin-Wohlman, O Korenblit, IY Harris, AB Erwin, RW Shirane, G TI Neutron scattering study of Sr2Cu3O4Cl2 SO PHYSICAL REVIEW B LA English DT Article ID LATTICE HEISENBERG-ANTIFERROMAGNET; SQUARE-LATTICE; SPIN CORRELATIONS; QUANTUM FLUCTUATIONS; ELECTRONIC-STRUCTURE; MAGNETIC-PROPERTIES; CRITICAL-BEHAVIOR; ZERO TEMPERATURE; CU3O4 PLANE; MAGNON GAP AB We report a neutron scattering study on the tetragonal compound Sr2Cu3O4Cl2, which has two-dimensional (2D) interpenetrating Cu-I and Cu-II subsystems, each forming a S=1/2 square lattice quantum Heisenberg antiferromagnet (SLQHA). The mean-field ground state is degenerate, since the intersubsystem interactions are geometrically frustrated. Magnetic neutron scattering experiments show that quantum fluctuations lift the degeneracy and cause a 2D Ising ordering of the Cu-II subsystem. Due to quantum fluctuations a dramatic increase of the Cu-I out-of-plane spin-wave gap is also observed. The temperature dependence and the dispersion of the spin-wave energy are quantitatively explained by spin-wave calculations which include quantum fluctuations explicitly. The values for the nearest-neighbor superexchange interactions between the Cu-I and Cu-II ions and between the Cu-II ions are determined experimentally to be J(I-II) = -10(2) meV and J(II) = 10.5(5) meV, respectively. Due to its small exchange interaction J(II), the 2D dispersion of the Cu-II SLQHA can be measured over the whole Brillouin zone with thermal neutrons, and a dispersion at the zone boundary, predicted by theory, is confirmed. The instantaneous magnetic correlation length of the Cu-II SLQHA is obtained up to a very high temperature, T/J(II)approximate to0.75. This result is compared with several theoretical predictions as well as recent experiments on the S=1/2 SLQHA. C1 Harvard Univ, Div Engn & Appl Sci, Cambridge, MA 02138 USA. MIT, Ctr Mat Sci & Engn, Cambridge, MA 02139 USA. Tel Aviv Univ, Sch Phys & Astron, IL-69978 Tel Aviv, Israel. Univ Penn, Dept Phys, Philadelphia, PA 19104 USA. Natl Inst Stand & Technol, Ctr Neutron Res, Gaithersburg, MD 20899 USA. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Univ Toronto, Dept Phys, Toronto, ON M5S 1A7, Canada. RP Kim, YJ (reprint author), Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RI Kim, Young-June /G-7196-2011; ENTIN, ORA/F-1114-2012; harris, A Brooks/C-8640-2013 OI Kim, Young-June /0000-0002-1172-8895; NR 74 TC 26 Z9 26 U1 1 U2 10 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 JUL 1 PY 2001 VL 64 IS 2 AR 024435 DI 10.1103/PhysRevB.64.024435 PG 19 WC Physics, Condensed Matter SC Physics GA 452AV UT WOS:000169835700076 ER PT J AU Lin, Y Eldridge, JE Schlueter, J Wang, HH Kini, AM AF Lin, Y Eldridge, JE Schlueter, J Wang, HH Kini, AM TI Raman studies of BEDT-TTF molecule-based organic superconductors SO PHYSICAL REVIEW B LA English DT Article ID C-13 NMR; TRI-IODIDE; X-RAY; KAPPA-(BEDT-TTF)(2)CUBR; PHONON; PHASE; BIS(ETHYLENEDITHIO)TETRATHIAFULVALENE; FLUCTUATIONS; SCATTERING; TRANSITION AB The temperature dependence of the frequencies of the Raman features due to nu (9) (A(g)) and nu (60) (B-3g) modes has been measured in the BEDT-TTF (ET) molecule-based organic superconductors kappa-(ET)(2)Cu[N(CN)(2)]Br, kappa-(ET)(2)Cu[N(CN)(2)]Cl, alpha (t)(ET)(2)I-3, and beta-(ET)(2)AuI2. The frequency of the nu (9) (A(g)) mode was observed to soften in kappa-(ET)(2)Cu[N(CN)(2)]Br and kappa-(ET)(2)Cu[N(CN)(2)]Cl at low temperatures where NMR data indicated antiferromagnetic fluctuations, providing evidence of spin-phonon interactions. The result is also compared with a very recent theory which deals with the effect of electronic correlations on the frequencies of the molecular phonon modes. We observed a peak splitting for the nu (60) (B-3g) mode in alpha (t)-(ET)(2)I-3 below 190 K, where an incommensurate superstructure was reported, and a frequency decrease of 1.7 +/-0.4 cm(-1) for the upper component of the nu (60) (B-3g) mode in the superconducting compound, demonstrating further the unusual properties of this mode. C1 Univ British Columbia, Dept Phys, Vancouver, BC V6T 1Z1, Canada. Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Lin, Y (reprint author), Univ British Columbia, Dept Phys, Vancouver, BC V6T 1Z1, Canada. RI Kini, Aravinda/F-4467-2012 NR 21 TC 4 Z9 4 U1 0 U2 2 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 JUL 1 PY 2001 VL 64 IS 2 AR 024506 DI 10.1103/PhysRevB.64.024506 PG 5 WC Physics, Condensed Matter SC Physics GA 452AV UT WOS:000169835700083 ER PT J AU Mandrus, D Sales, BC Jin, R AF Mandrus, D Sales, BC Jin, R TI Localized vibrational mode analysis of the resistivity and specific heat of LaB6 SO PHYSICAL REVIEW B LA English DT Article ID ATOMIC DISPLACEMENT PARAMETERS; LATTICE-DYNAMICS; YBB6 AB LaB6 and other hexaborides are inclusion compounds in which the rare earth or other metal ion is weakly bound and sits in an oversized "cage" of boron ions. Here we show that a simple model that treats the La ions as independent harmonic (Einstein) oscillators embedded in a Debye framework of boron ions successfully accounts for the anomalies in the specific heat and resistivity of LaB6. One of the nice features of the model is that the Einstein temperature of the La atoms and the Debye temperature of the boron framework are derived from room-temperature x-ray crystallography data. This feature makes the model easy to apply to other hexaborides and other materials that can be treated as inclusion compounds. The results from this work imply that local modes are likely to be important for understanding the physical properties of all the hexaborides. C1 Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Mandrus, D (reprint author), Oak Ridge Natl Lab, Div Solid State, POB 2008, Oak Ridge, TN 37831 USA. EM mandrusdg@ornl.gov RI Mandrus, David/H-3090-2014 NR 15 TC 45 Z9 47 U1 0 U2 24 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 JUL 1 PY 2001 VL 64 IS 1 AR 012302 DI 10.1103/PhysRevB.64.012302 PG 4 WC Physics, Condensed Matter SC Physics GA 449XF UT WOS:000169711900006 ER PT J AU Manosa, L Planes, A Zarestky, J Lograsso, T Schlagel, DL Stassis, C AF Manosa, L Planes, A Zarestky, J Lograsso, T Schlagel, DL Stassis, C TI Phonon softening in Ni-Mn-Ga alloys SO PHYSICAL REVIEW B LA English DT Article ID FIELD-INDUCED STRAINS; BETA-PHASE; PREMARTENSITIC TRANSITION; FERROMAGNETIC NI2MNGA; NEUTRON-SCATTERING; ANOMALIES; BEHAVIOR AB The TA(2) phonon dispersion curves of Ni-Mn-Ga alloys with different compositions which transform to different martensitic structures have been measured over a broad temperature range covering both paramagnetic and ferromagnetic phases. The branches show an anomaly (dip) at a wave number that depends on the particular martensitic structure, and there is softening of these anomalous phonons with decreasing temperature. This softening is enhanced below the Curie point, as a consequence of spin-phonon coupling. This effect is stronger for systems with higher electronic concentration. C1 Univ Barcelona, Dept Estructura & Constituents Mat, Fac Fis, E-08028 Barcelona, Spain. Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Dept Phys & Astron, Ames, IA 50011 USA. RP Manosa, L (reprint author), Univ Barcelona, Dept Estructura & Constituents Mat, Fac Fis, Avinguda Diagonal 647, E-08028 Barcelona, Spain. RI Manosa, Lluis/D-8579-2014; Planes, Antoni/O-1904-2015 OI Manosa, Lluis/0000-0002-1182-2670; Planes, Antoni/0000-0001-5213-5714 NR 22 TC 76 Z9 76 U1 1 U2 21 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 JUL 1 PY 2001 VL 64 IS 2 AR 024305 DI 10.1103/PhysRevB.64.024305 PG 6 WC Physics, Condensed Matter SC Physics GA 452AV UT WOS:000169835700041 ER PT J AU Martinho, H Moreno, NO Sanjurjo, JA Rettori, C Garcia-Adeva, AJ Huber, DL Oseroff, SB Ratcliff, W Cheong, SW Pagliuso, PG Sarrao, JL Martins, GB AF Martinho, H Moreno, NO Sanjurjo, JA Rettori, C Garcia-Adeva, AJ Huber, DL Oseroff, SB Ratcliff, W Cheong, SW Pagliuso, PG Sarrao, JL Martins, GB TI Magnetic properties of the frustrated antiferromagnetic spinel ZnCr2O4 and the spin-glass Zn1-xCdxCr2O4 (x=0.05,0.10) SO PHYSICAL REVIEW B LA English DT Article ID PYROCHLORE ANTIFERROMAGNET; RESONANCE LINEWIDTH; PHASE-TRANSITION; LATTICE; LIQUID AB The T dependence (2-400 K) of the electron paramagnetic resonance (EPR). magnetic susceptibility chi (T), and specific heat C-v(T) of the normal antiferromagnetic (AFM) spinel ZnCr2O4 and the spin-glass (SG) Zn1-xCdxCr2O4 (x = 0.05.0.10) are reported. These systems behave as a strongly frustrated AFM and SG with T(N)approximate toT(G)approximate to 12 K and -400 K greater than or similar to Theta (CW)greater than or similar to -500 K. At high-ir the EPR intensity follows the chi (T) and the g value is T independent. The linewidth broadens as the temperature is lowered, suggesting the existence of short range AFM correlations in the paramagnetic phase. For ZnCr2O4 the EPR intensity and chi (T) decreases below 90 and 50 K, respectively. These results are discussed in terms of both nearest-neighbor Cr3+ (S=3/2) spin-coupled pairs and spin-coupled tetrahedral clusters with an exchange coupling of \J/k\ approximate to 35-45 K. The appearance of small resonance modes for T less than or similar to 17 K. the observation of a sharp drop in chi (T) and a strong peak in C-v(T) at T-N=12 K confirms, as previously reported, the existence of long range AFM correlations in the low-T phase. A comparison with recent neutron diffraction experiments, that found a near dispersionless excitation at 4.5 meV for T less than or similar toT(N) and a continuous gapless spectrum for T greater than or similar toT(N), is also given. C1 UNICAMP, Inst Fis Gleb Wataghin, BR-13083970 Campinas, SP, Brazil. Univ Wisconsin, Madison, WI 53706 USA. San Diego State Univ, San Diego, CA 92182 USA. Rutgers State Univ, Dept Phys & Astron, Piscataway, NJ 08854 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Florida State Univ, Natl High Magnet Field Lab, Tallahassee, FL 32306 USA. RP Martinho, H (reprint author), UNICAMP, Inst Fis Gleb Wataghin, BR-13083970 Campinas, SP, Brazil. RI Rettori, Carlos/C-3966-2012; Pagliuso, Pascoal/C-9169-2012; Moreno, Nelson/H-1708-2012; Garcia Adeva, Angel/L-5157-2014; Martinho, Herculano/F-4684-2015; Martins, George/C-9756-2012; Optica e Eletronica, Laboratorio/A-8669-2014; Inst. of Physics, Gleb Wataghin/A-9780-2017 OI Rettori, Carlos/0000-0001-6692-7915; Moreno, Nelson/0000-0002-1672-4340; Garcia Adeva, Angel/0000-0003-2776-2390; Martins, George/0000-0001-7846-708X; NR 30 TC 61 Z9 62 U1 2 U2 42 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 JUL 1 PY 2001 VL 64 IS 2 AR 024408 DI 10.1103/PhysRevB.64.024408 PG 6 WC Physics, Condensed Matter SC Physics GA 452AV UT WOS:000169835700049 ER PT J AU Mazumdar, C Hu, Z von Lips, H Golden, MS Fink, J Canfield, PC Kaindl, G AF Mazumdar, C Hu, Z von Lips, H Golden, MS Fink, J Canfield, PC Kaindl, G TI Polarization-dependent x-ray-absorption spectroscopy of RNi2B2C (R = Er to Lu): Reduced Ni-3d occupancy in YbNi2B2C SO PHYSICAL REVIEW B LA English DT Article ID SUPERCONDUCTING LUNI2B2C; ELECTRONIC-STRUCTURE; BORIDE CARBIDE; HEAVY-FERMION; YNI2B2C; EARTH; SUPPRESSION; MAGNETISM; BEHAVIOR; SYSTEM AB We present here the results of polarization-dependent x-ray-absorption near-edge structure (XANES) studies at the B-K, C-K, and Ni-L-3 thresholds of single-crystalline borocarbide compounds RNi2B2C (with R = Er to Lu) using bulk-sensitive fluorescence yield technique. The Ni-L3 XANES spectrum for YbNi2B2C with photon polarization parallel to the ab plane is significantly more intense than in analogous spectra of other members of this series. This indicates a reduced Ni-3d occupancy in the Ni2B2 layer in YbNi2B2C, a fact that might be responsible for the absence of superconductivity in this material. C1 Free Univ Berlin, Inst Phys Expt, D-14195 Berlin, Germany. Inst Solid State & Mat Res IFW, D-01171 Dresden, Germany. Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. RP Mazumdar, C (reprint author), Free Univ Berlin, Inst Phys Expt, Arnimallee 14, D-14195 Berlin, Germany. RI Hu, Zhiwei/B-8635-2008; Fink, Joerg/A-6003-2012; Canfield, Paul/H-2698-2014; Golden, Mark/D-3469-2011 NR 30 TC 2 Z9 2 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD JUL 1 PY 2001 VL 64 IS 2 AR 020504 DI 10.1103/PhysRevB.64.020504 PG 4 WC Physics, Condensed Matter SC Physics GA 452AV UT WOS:000169835700016 ER PT J AU Mook, HA Dai, PC Dogan, F AF Mook, HA Dai, PC Dogan, F TI Observation of magnetic moments in the superconducting state of YBa2Cu3O6.6 SO PHYSICAL REVIEW B LA English DT Article ID ANTIFERROMAGNETISM; FLUCTUATIONS AB Neutron scattering measurements for YBa2Cu3O6.6 have identified small magnetic moments that increase in strength as the temperature is reduced below T* and further increase below T-c. An analysis of the data shows the moments are antiferromagnetic between the Cu-O planes with a correlation length of longer than 195 Angstrom in the a-b plane and about 35 Angstrom along the c axis. The origin of the moments is unknown, and their properties are discussed both in terms of Cu spin magnetism and orbital bond currents. C1 Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Univ Washington, Dept Mat Sci & Engn, Seattle, WA 98195 USA. RP Mook, HA (reprint author), Oak Ridge Natl Lab, Div Solid State, POB 2008, Oak Ridge, TN 37831 USA. RI Dai, Pengcheng /C-9171-2012 OI Dai, Pengcheng /0000-0002-6088-3170 NR 13 TC 62 Z9 62 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 JUL 1 PY 2001 VL 64 IS 1 AR 012502 DI 10.1103/PhysRevB.64.012502 PG 4 WC Physics, Condensed Matter SC Physics GA 449XF UT WOS:000169711900027 ER PT J AU Qian, Q Tyson, TA Kao, CC Croft, M Cheong, SW Popov, G Greenblatt, M AF Qian, Q Tyson, TA Kao, CC Croft, M Cheong, SW Popov, G Greenblatt, M TI Local structural distortions in manganites probed by comparative x-ray-emission and x-ray-absorption near-edge measurements SO PHYSICAL REVIEW B LA English DT Article ID CONJUGATE-GRADIENT-METHOD; JAHN-TELLER DISTORTION; MN K-EDGE; FINE-STRUCTURE; ELECTRONIC-STRUCTURE; NEUTRON-DIFFRACTION; LA1-XCAXMNO3; SCATTERING; LAMNO3; MAGNETORESISTANCE AB Comparison studies of the perovskite compounds system R1-xCaxMnO3 (R=La,Bi) by both Mn K-beta-emission spectroscopy and x-ray-absorption near-edge spectroscopy (XANES) are presented. The insensitivity of x-ray-emission measurements to structural distortions coupled with the sensitivity of x-ray-absorption near-edge measurements to changes in both structure and valence enable one to detect the presence of structural distortions, such as local Jahn-Teller (JT) distortions. Theoretical XANES computations fur pure cubic perovskite and locally distorted endmembers are used to show the effect of distortions on XANES spectra as well as to comment on the nature of the pre-edge features in the spectra. We show by explicit computations: that the near-edge spectra are determined by dipole transitions while pure 1s to 3d electric quadrupole transitions determine a very limited section of the pre-edge region. Simulations of the pre-edge features reveal a direct connection between local distortions and the a1 feature amplitude. The Bi-containing system is found to have significantly higher levels of distortions than the La system. XANES studies of the A MnO3 (A = La, Pr, and Nd) system reveal a direct relationship between the main line width and the magnitude of the JT distortions. C1 New Jersey Inst Technol, Dept Phys, Newark, NJ 07102 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. Rutgers State Univ, Dept Phys & Astron, Piscataway, NJ 08854 USA. Rutgers State Univ, Dept Chem, Piscataway, NJ 08854 USA. RP Qian, Q (reprint author), New Jersey Inst Technol, Dept Phys, Newark, NJ 07102 USA. NR 35 TC 27 Z9 27 U1 1 U2 9 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 JUL 1 PY 2001 VL 64 IS 2 AR 024430 DI 10.1103/PhysRevB.64.024430 PG 7 WC Physics, Condensed Matter SC Physics GA 452AV UT WOS:000169835700071 ER PT J AU Reichhardt, C Zimanyi, GT Gronbech-Jensen, N AF Reichhardt, C Zimanyi, GT Gronbech-Jensen, N TI Complex dynamical flow phases and pinning in superconductors with rectangular pinning arrays SO PHYSICAL REVIEW B LA English DT Article ID FLUX-LINE-LATTICE; JOSEPHSON-JUNCTION ARRAYS; DRIVEN VORTEX LATTICES; MOVING GLASS PHASE; SQUARE LATTICE; THIN-FILMS; ANTIDOT LATTICE; PERIODIC MEDIA; LOGARITHMIC INTERACTIONS; CRITICAL CURRENTS AB We examine vortex pinning and dynamics in thin-film superconductors containing logarithmically interacting Pearl vortices moving through square and rectangular pinning arrays for varied vortex densities including densities significantly larger than the pinning density. For both square and rectangular pinning arrays, the critical depinning force shows maxima only at certain integer matching fields where the vortices can form highly ordered lattices. For rectangular arrays the depinning force and commensurability effects rue anisotropic, with a much lower depinning threshold for vortex motion in the easy-flow directions. We find evidence for a crossover in pinning behavior in rectangular pinning arrays as the field is increased. We also show analytically, and confirm with simulations, that for B = 2B(phi) the strongest pinning for one direction of the driving force can be achieved for rectangular pinning arrangements rather than square ones. Under an applied driving force we find a remarkable variety of distinct complex flow phase: in both square and rectangular arrays. These flow phases include stable sinusoidal and intricate pinched patterns where vortices from different channels do not mix. As a function of the driving force certain flow states become unstable and transitions between different phases are observed that coincide with changes in the net vortex velocities. In the rectangular arrays the types of flow observed depend on the direction of drive. We also show that two general types of plastic flow occur: stable flows, where vortices always flow along the same paths, and unstable or chaotic flows. C1 Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. Univ Calif Davis, Dept Appl Sci, Davis, CA 95616 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, NERSC, Berkeley, CA 94720 USA. RP Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. NR 74 TC 76 Z9 76 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 JUL 1 PY 2001 VL 64 IS 1 AR 014501 DI 10.1103/PhysRevB.64.014501 PG 14 WC Physics, Condensed Matter SC Physics GA 449XF UT WOS:000169711900077 ER PT J AU Silhanek, AV Thompson, JR Civale, L Paul, DM Tomy, CV AF Silhanek, AV Thompson, JR Civale, L Paul, DM Tomy, CV TI Influence of nonlocal electrodynamics on the anisotropic vortex pinning in YNi2B2C SO PHYSICAL REVIEW B LA English DT Article ID FLUX-LINE-LATTICE; TETRAGONAL SUPERCONDUCTORS; NEUTRON-SCATTERING; MAGNETIZATION; TRANSITION; MECHANISMS AB We have studied the pinning force density F-p of YNi2B2C superconductors for various field orientations. We observe anisotropies both between the c axis and the basal plane and within the plane that cannot be explained by the usual mass anisotropy. For magnetic field H parallel toc, the reorientation structural transition in the vortex lattice due to nonlocality, which occurs at a field H(1)similar to1 kOe, manifests itself as a kink in F-p(H). When H perpendicular toc, F-p is much larger and has a quite different H dependence, indicating that other pinning mechanisms are present. In this case the signature of nonlocal effects is the presence of a fourfold periodicity of F-p within the basal plane. C1 Comis Nacl Energia Atom, Ctr Atom Bariloche, RA-8400 Bariloche, Rio Negro, Argentina. Inst Balseiro, RA-8400 Bariloche, Rio Negro, Argentina. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Univ Tennessee, Dept Phys, Knoxville, TN 37996 USA. Indian Inst Technol, Dept Phys, Mumbai 400076, India. RP Silhanek, AV (reprint author), Comis Nacl Energia Atom, Ctr Atom Bariloche, RA-8400 Bariloche, Rio Negro, Argentina. NR 19 TC 6 Z9 6 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD JUL 1 PY 2001 VL 64 IS 1 AR 012512 DI 10.1103/PhysRevB.64.012512 PG 4 WC Physics, Condensed Matter SC Physics GA 449XF UT WOS:000169711900037 ER PT J AU Song, C Lang, JC Detlefs, C Letoublon, A Good, W Kim, J Wermeille, D Bud'ko, SL Canfield, PC Goldman, AI AF Song, C Lang, JC Detlefs, C Letoublon, A Good, W Kim, J Wermeille, D Bud'ko, SL Canfield, PC Goldman, AI TI X-ray magnetic circular dichroism study of TbNi2B2C SO PHYSICAL REVIEW B LA English DT Article ID WEAK FERROMAGNETISM; SUPERCONDUCTIVITY; ERNI2B2C; STATE AB X-ray magnetic circular dichroism measurements were performed on TbNi2B2C in order to confirm the weak ferromagnetism reported for this material at low temperatures. Below approximately 8 K, an increase in the dichroic signal was observed at the Tb L-III edge, consistent with the onset of weak ferromagnetism involving the Tb ions. At an external magnetic field of 500 G, the ferromagnetic order parameter was obtained, and is in good agreement with the bulk magnetization data measured by a SQUID magnetometer. C1 Iowa State Univ, Ames Lab, US DOE, Ames, IA 50011 USA. Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. European Synchrotron Radiat Facil, F-38043 Grenoble, France. RP Song, C (reprint author), Iowa State Univ, Ames Lab, US DOE, Ames, IA 50011 USA. RI Detlefs, Carsten/B-6244-2008; Canfield, Paul/H-2698-2014 OI Detlefs, Carsten/0000-0003-2573-2286; NR 23 TC 7 Z9 7 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD JUL 1 PY 2001 VL 64 IS 2 AR 020403 DI 10.1103/PhysRevB.64.020403 PG 4 WC Physics, Condensed Matter SC Physics GA 452AV UT WOS:000169835700008 ER PT J AU Suderow, H Martinez-Samper, P Luchier, N Brison, JP Vieira, S Canfield, PC AF Suderow, H Martinez-Samper, P Luchier, N Brison, JP Vieira, S Canfield, PC TI Tunneling spectroscopy in the magnetic superconductor TmNi2B2C SO PHYSICAL REVIEW B LA English DT Article ID FLUX-LINE-LATTICE; UPPER CRITICAL-FIELD; SINGLE-CRYSTAL; ENERGY-GAP; YNI2B2C; TRANSITION; STATE; LUNI2B2C; LU(NI1-XCOX)(2)B2C; BOROCARBIDES AB We present measurements of the tunneling conductance in the borocarbide superconductor TmNi2B2C. The results show a very good agreement with the weak coupling BCS theory, without any lifetime broadening parameter, over the whole sample surface. We detect no particular change of the tunneling spectroscopy below 1.5 K, when both the antiferromagnetic (AF) phase and the superconducting order coexist. C1 CSIC, Inst Ciencia Mat Madrid, Madrid 28049, Spain. Univ Autonoma Madrid CIII, Fac Ciencias, Inst Ciencia Mat Nicolas Cabrera, Lab Bajas Temp,Dept Fis Mat Condensada, Madrid 28049, Spain. CNRS, Ctr Rech Tres Basses Temp, F-38042 Grenoble 9, France. Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. RP Suderow, H (reprint author), CSIC, Inst Ciencia Mat Madrid, CAmpus Cantoblanco, Madrid 28049, Spain. RI Suderow, Hermann/L-6612-2013; Canfield, Paul/H-2698-2014; vieira, sebastian/L-5216-2014 OI Suderow, Hermann/0000-0002-5902-1880; vieira, sebastian/0000-0002-3854-1377 NR 39 TC 23 Z9 23 U1 0 U2 2 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 JUL 1 PY 2001 VL 64 IS 2 AR 020503 DI 10.1103/PhysRevB.64.020503 PG 4 WC Physics, Condensed Matter SC Physics GA 452AV UT WOS:000169835700015 ER PT J AU Thompson, JR Silhanek, AV Civale, L Song, KJ Tomy, CV Paul, DM AF Thompson, JR Silhanek, AV Civale, L Song, KJ Tomy, CV Paul, DM TI Equilibrium basal-plane magnetization of superconductive YNi2B2C: The influence of nonlocal electrodynamics SO PHYSICAL REVIEW B LA English DT Article ID VORTEX LATTICE TRANSITIONS; UPPER CRITICAL-FIELD; ANISOTROPY; MAGNETISM; STATE; ERNI2B2C; TMNI2B2C; LUNI2B2C AB For a single crystal of YNi2B2C superconductor, the equilibrium magnetization M in the square basal Plane has been studied experimentally as a function of temperature and magnetic field. While the magnetization M(H) deviates from conventional London predictions, a recent extension of London theory (to include effects of nonlocal electrodynamics) describes the experiments accurately. The resulting superconductive parameters are well behaved. These results are compared with corresponding findings for the case with M perpendicular to the basal plane. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Univ Tennessee, Dept Phys, Knoxville, TN 37996 USA. Comis Nacl Energia Atom, Ctr Atom Bariloche, RA-8400 San Carlos De Bariloche, Rio Negro, Argentina. Inst Balseiro, RA-8400 San Carlos De Bariloche, Rio Negro, Argentina. Indian Inst Technol, Dept Phys, Mumbai 400076, India. Univ Warwick, Dept Phys, Coventry CV4 7AL, W Midlands, England. RP Thompson, JR (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. NR 22 TC 7 Z9 7 U1 0 U2 2 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 JUL 1 PY 2001 VL 64 IS 2 AR 024510 DI 10.1103/PhysRevB.64.024510 PG 7 WC Physics, Condensed Matter SC Physics GA 452AV UT WOS:000169835700087 ER PT J AU Vinnikov, LY Barkov, TL Canfield, PC Bud'ko, SL Kogan, VG AF Vinnikov, LY Barkov, TL Canfield, PC Bud'ko, SL Kogan, VG TI Field evolution of vortex lattice in LuNi2B2C seen by decoration in fields up to 1.5 kOe SO PHYSICAL REVIEW B LA English DT Article ID FLUX-LINE-LATTICE; SINGLE-CRYSTALS; SUPERCONDUCTORS; TRANSITION; YNI2B2C AB Evolution of the vortex lattice, the rhombus-square transition included, for LuNi2B2C in the field along the c crystal axis, is tracked by the decoration technique pushed up to the record high (for this method) field of. 1480 Oe. Decoration images are analyzed with the help of the Fourier transform, which indicates disordered structures in small fields of a few Oe. In fields H<200 Oe the coexisting domains of different structures are observed. A technique based on the Fourier transform is employed to see the domains separately. The transition to the square lattice is recorded near 900 Oe. The results are in agreement with predictions of the nonlocal London theory. C1 Russian Acad Sci, Inst Solid State Phys, Chernogolovka 142432, Moscow Region, Russia. Iowa State Univ, US DOE, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Phys, Ames, IA 50011 USA. RP Vinnikov, LY (reprint author), Russian Acad Sci, Inst Solid State Phys, Chernogolovka 142432, Moscow Region, Russia. RI Canfield, Paul/H-2698-2014 NR 22 TC 24 Z9 24 U1 0 U2 3 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 JUL 1 PY 2001 VL 64 IS 2 AR 024504 DI 10.1103/PhysRevB.64.024504 PG 6 WC Physics, Condensed Matter SC Physics GA 452AV UT WOS:000169835700081 ER PT J AU Voulgarakis, NK Kalosakas, G Bishop, AR Tsironis, GP AF Voulgarakis, NK Kalosakas, G Bishop, AR Tsironis, GP TI Multiquanta breather model for PtCl SO PHYSICAL REVIEW B LA English DT Article ID NONLINEAR LATTICES; QUANTUM BREATHERS; LOCALIZED MODES; ACETANILIDE; SPECTRUM; SOLITON; RELAXATION; EXISTENCE; COMPLEXES; CRYSTALS AB We study the many-quanta problem of an intramolecular vibrational excitation interacting with optical phonons, that may represent the nonlinearity from intrinsic electron-lattice interactions. In the adiabatic limit we calculate numerically the ground-state energy and the corresponding wave functions for N vibrational quanta. In the one-dimensional case we find strong redshifts in the overtone spectra and an increasing spatial localization as the number of quanta increases. Through model parameter fitting we achieve very good quantitative agreement with experimental resonant Raman scattering measurements in the quasi-one-dimensional charge transfer solid PtCl. Accurate analytical expressions for the redshifts are also obtained. C1 Univ Crete, Dept Phys, Heraklion 71003, Crete, Greece. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Voulgarakis, NK (reprint author), Univ Crete, Dept Phys, POB 2208, Heraklion 71003, Crete, Greece. RI Voulgarakis, Nikolaos/A-8711-2010; Tsironis, George/C-2683-2011; Kalosakas, George/L-6211-2013 OI Kalosakas, George/0000-0001-7763-718X NR 30 TC 18 Z9 19 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 JUL 1 PY 2001 VL 64 IS 2 AR 020301 DI 10.1103/PhysRevB.64.020301 PG 4 WC Physics, Condensed Matter SC Physics GA 452AV UT WOS:000169835700004 ER PT J AU Aggarwal, MM Agnihotri, A Ahammed, Z Angelis, ALS Antonenko, V Arefiev, V Astakhov, V Avdeitchikov, V Awes, TC Baba, PVKS Badyal, SK Barlag, C Bathe, S Batiounia, B Bernier, T Bhalla, KB Bhatia, VS Blume, C Bock, R Bohne, EM Borocz, Z Bucher, D Buijs, A Busching, H Carlen, L Chalyshev, V Chattopadhyay, S Cherbatchev, R Chujo, T Claussen, A Das, AC Decowski, MP Delagrange, H Djordjadze, V Donni, P Doubovik, I Dubey, AK Dutt, S Majumdar, MRD El Chenawi, K Eliseev, S Enosawa, K Foka, P Fokin, S Ganti, MS Garpman, S Gavrishchuk, O Geurts, FJM Ghosh, TK Glasow, R Gupta, SK Guskov, B Gustafsson, HA Gutbrod, HH Higuchi, R Hrivnacova, I Ippolitov, M Kalechofsky, H Kamermans, R Kampert, KH Karadjev, K Karpio, K Kato, S Kees, S Klein-Bosing, C Knoche, S Kolb, BW Kosarev, I Koutcheryaev, I Krumpel, T Kugler, A Kulinich, P Kurata, M Kurita, K Kuzmin, N Langbein, I Lebedev, A Lee, YY Lohner, H Luquin, L Mahapatra, DP Manko, V Martin, M Martinez, G Maximov, A Mgebrichvili, G Miake, Y Mir, MF Mishra, GC Miyamoto, Y Mohanty, B Mora, MJ Morrison, D Mukhopadhyay, DS Naef, H Nandi, BK Nayak, SK Nayak, TK Neumaier, S Nianine, A Nikitine, V Nikolaev, S Nilsson, P Nishimura, S Nomokonov, P Nystrand, J Obenshain, FE Oskarsson, A Otterlund, I Pachr, M Pavliouk, S Peitzmann, T Petracek, V Pinganaud, W Plasil, F von Poblotzki, U Purschke, ML Rak, J Raniwala, R Raniwala, S Ramamurthy, VS Rao, NK Retiere, F Reygers, K Roland, G Rosselet, L Roufanov, I Roy, C Rubio, JM Sako, H Sambyal, SS Santo, R Sato, S Schlagheck, H Schmidt, HR Schutz, Y Shabratova, G Shah, TH Sibiriak, I Siemiarczuk, T Silvermyr, D Sinha, BC Slavine, N Soderstrom, K Solomey, N Sood, G Sorensen, SP Stankus, P Stefanek, G Steinberg, P Stenlund, E Stuken, D Sumbera, M Svensson, T Trivedi, MD Tsvetkov, A Tykarski, L Urbahn, J von der Pijll, EC von Eijndhoven, N von Nieuwenhuizen, GJ Vinogradov, A Viyogi, YP Vodopianov, AV Voros, S Wyslouch, B Yagi, K Yokota, Y Young, GR AF Aggarwal, MM Agnihotri, A Ahammed, Z Angelis, ALS Antonenko, V Arefiev, V Astakhov, V Avdeitchikov, V Awes, TC Baba, PVKS Badyal, SK Barlag, C Bathe, S Batiounia, B Bernier, T Bhalla, KB Bhatia, VS Blume, C Bock, R Bohne, EM Borocz, Z Bucher, D Buijs, A Busching, H Carlen, L Chalyshev, V Chattopadhyay, S Cherbatchev, R Chujo, T Claussen, A Das, AC Decowski, MP Delagrange, H Djordjadze, V Donni, P Doubovik, I Dubey, AK Dutt, S Majumdar, MRD El Chenawi, K Eliseev, S Enosawa, K Foka, P Fokin, S Ganti, MS Garpman, S Gavrishchuk, O Geurts, FJM Ghosh, TK Glasow, R Gupta, SK Guskov, B Gustafsson, HA Gutbrod, HH Higuchi, R Hrivnacova, I Ippolitov, M Kalechofsky, H Kamermans, R Kampert, KH Karadjev, K Karpio, K Kato, S Kees, S Klein-Bosing, C Knoche, S Kolb, BW Kosarev, I Koutcheryaev, I Krumpel, T Kugler, A Kulinich, P Kurata, M Kurita, K Kuzmin, N Langbein, I Lebedev, A Lee, YY Lohner, H Luquin, L Mahapatra, DP Manko, V Martin, M Martinez, G Maximov, A Mgebrichvili, G Miake, Y Mir, MF Mishra, GC Miyamoto, Y Mohanty, B Mora, MJ Morrison, D Mukhopadhyay, DS Naef, H Nandi, BK Nayak, SK Nayak, TK Neumaier, S Nianine, A Nikitine, V Nikolaev, S Nilsson, P Nishimura, S Nomokonov, P Nystrand, J Obenshain, FE Oskarsson, A Otterlund, I Pachr, M Pavliouk, S Peitzmann, T Petracek, V Pinganaud, W Plasil, F von Poblotzki, U Purschke, ML Rak, J Raniwala, R Raniwala, S Ramamurthy, VS Rao, NK Retiere, F Reygers, K Roland, G Rosselet, L Roufanov, I Roy, C Rubio, JM Sako, H Sambyal, SS Santo, R Sato, S Schlagheck, H Schmidt, HR Schutz, Y Shabratova, G Shah, TH Sibiriak, I Siemiarczuk, T Silvermyr, D Sinha, BC Slavine, N Soderstrom, K Solomey, N Sood, G Sorensen, SP Stankus, P Stefanek, G Steinberg, P Stenlund, E Stuken, D Sumbera, M Svensson, T Trivedi, MD Tsvetkov, A Tykarski, L Urbahn, J von der Pijll, EC von Eijndhoven, N von Nieuwenhuizen, GJ Vinogradov, A Viyogi, YP Vodopianov, AV Voros, S Wyslouch, B Yagi, K Yokota, Y Young, GR CA WA98 Collaboration TI Localized charged-neutral fluctuations in 158A GeVPb plus Pb collisions SO PHYSICAL REVIEW C LA English DT Article ID DISORIENTED CHIRAL CONDENSATE; HIGH-ENERGY COLLISIONS; HADRONIC-INTERACTIONS; PB+PB COLLISIONS; WA98 EXPERIMENT; SEARCH; QCD; DETECTOR; DOMAINS AB Localized fluctuations in the multiplicity of charged particles and photons produced in central 158A GeV/c Pb+Pb collisions are studied. The charged versus neutral correlations in common eta-phi phase space regions of varying azimuthal size are analyzed by two different methods. The analysis provides a model-independent demonstration of nonstatistical fluctuations in both charged particle and photon multiplicities in limited azimuthal regions. However, no correlated charge-neutral fluctuations are observed, contrary to expectations for the production of a disoriented chiral condensate. The result is not explained by the widely used VENUS model. C1 Panjab Univ, Chandigarh 160014, India. Univ Rajasthan, Jaipur 302004, Rajasthan, India. Bhabha Atom Res Ctr, Ctr Variable Energy Cyclotron, Kolkata 700064, W Bengal, India. Univ Geneva, CH-1211 Geneva 4, Switzerland. RRC Kurchatov Inst, RU-123182 Moscow, Russia. Joint Inst Nucl Res, RU-141980 Dubna, Russia. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Univ Jammu, Jammu 180001, India. Univ Munster, D-48149 Munster, Germany. Ecole Mines, SUBATECH, Nantes, France. Gesell Schwerionenforsch GSI, D-64220 Darmstadt, Germany. Univ Utrecht, NIKHEF, NL-3508 TA Utrecht, Netherlands. Lund Univ, SE-22100 Lund, Sweden. Univ Tsukuba, Tsukuba, Ibaraki 305, Japan. Nucl Res Inst, CZ-25068 Rez, Czech Republic. Univ Groningen, KVI, NL-9747 AA Groningen, Netherlands. Inst Nucl Studies, PL-00681 Warsaw, Poland. MIT, Cambridge, MA 02139 USA. Inst Phys, Bhubaneswar 751005, Orissa, India. Univ Tennessee, Knoxville, TN 37966 USA. RP Aggarwal, MM (reprint author), Panjab Univ, Chandigarh 160014, India. RI Decowski, Patrick/A-4341-2011; Peitzmann, Thomas/K-2206-2012; Lohner, Herbert/B-2397-2014; Sumbera, Michal/O-7497-2014; OI Peitzmann, Thomas/0000-0002-7116-899X; Lohner, Herbert/0000-0002-7441-739X; Sumbera, Michal/0000-0002-0639-7323; Mohanty, Bedangadas/0000-0001-9610-2914; Kampert, Karl-Heinz/0000-0002-2805-0195 NR 23 TC 38 Z9 38 U1 0 U2 4 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 EI 1089-490X J9 PHYS REV C JI Phys. Rev. C PD JUL PY 2001 VL 64 IS 1 AR 011901 DI 10.1103/PhysRevC.64.011901 PG 5 WC Physics, Nuclear SC Physics GA 452XB UT WOS:000169884000004 ER PT J AU Arrington, J Armstrong, CS Averett, T Baker, OK de Bever, L Bochna, CW Boeglin, W Bray, B Carlini, RD Collins, G Cothran, C Crabb, D Day, D Dunne, JA Dutta, D Ent, R Filippone, BW Honegger, A Hughes, EW Jensen, J Jourdan, J Keppel, CE Koltenuk, DM Lindgren, R Lung, A Mack, DJ McCarthy, J McKeown, RD Meekins, D Mitchell, JH Mkrtchyan, HG Niculescu, G Niculescu, I Petitjean, T Rondon, O Sick, I Smith, C Terburg, B Vulcan, WF Wood, SA Yan, C Zhao, J Zihlmann, B AF Arrington, J Armstrong, CS Averett, T Baker, OK de Bever, L Bochna, CW Boeglin, W Bray, B Carlini, RD Collins, G Cothran, C Crabb, D Day, D Dunne, JA Dutta, D Ent, R Filippone, BW Honegger, A Hughes, EW Jensen, J Jourdan, J Keppel, CE Koltenuk, DM Lindgren, R Lung, A Mack, DJ McCarthy, J McKeown, RD Meekins, D Mitchell, JH Mkrtchyan, HG Niculescu, G Niculescu, I Petitjean, T Rondon, O Sick, I Smith, C Terburg, B Vulcan, WF Wood, SA Yan, C Zhao, J Zihlmann, B TI x and xi scaling of the nuclear structure function at large x SO PHYSICAL REVIEW C LA English DT Article ID R=SIGMA-L/SIGMA-T; INELASTIC ELECTRON-SCATTERING; X-GREATER-THAN-1; DUALITY AB Inclusive electron scattering data are presented for H-2. C, Fe. and Au targets at an incident electron energy of 4.045 GeV for a range of momentum transfers from Q(2) = 1 to 7 (GeV/c)(2). Data were taken at Jefferson Laboratory for low values of energy loss, corresponding to values of Bjorken x greater than or similar to1. The structure functions do not show scaling in x in this range, where inelastic scattering is not expected to dominate the cross section. The data do show scaling, however, in the Nachtmann variable xi. This scaling appears to he the result of Bloom-Gilman duality in the nucleon structure function combined with the Fermi motion of the nucleons in the nucleus. The resulting extension of scaling to larger values of xi opens up the possibility of accessing nuclear structure functions in the high-x region at lower values of Q(2) than previously believed. C1 Argonne Natl Lab, Argonne, IL 60439 USA. Univ Basel, Basel, Switzerland. CALTECH, Kellogg Radiat Lab, Pasadena, CA 91125 USA. Florida Int Univ, Miami, FL 33199 USA. Hampton Univ, Hampton, VA 23668 USA. Univ Illinois, Urbana, IL 61801 USA. Univ Maryland, College Pk, MD 20742 USA. Northwestern Univ, Evanston, IL 60201 USA. Univ Penn, Philadelphia, PA 19104 USA. Thomas Jefferson Natl Accelerator Facil, Newport News, VA 23606 USA. Univ Virginia, Charlottesville, VA 22901 USA. Coll William & Mary, Williamsburg, VA 23187 USA. George Washington Univ, Washington, DC 20052 USA. Ohio Univ, Athens, OH 45701 USA. RP Arrington, J (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Averett, Todd/A-2969-2011; Arrington, John/D-1116-2012; Rondon Aramayo, Oscar/B-5880-2013; Day, Donal/C-5020-2015 OI Arrington, John/0000-0002-0702-1328; Day, Donal/0000-0001-7126-8934 NR 24 TC 34 Z9 34 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD JUL PY 2001 VL 64 IS 1 AR 014602 DI 10.1103/PhysRevC.64.014602 PG 5 WC Physics, Nuclear SC Physics GA 452XB UT WOS:000169884000024 ER PT J AU Bengtsson, R Moller, P AF Bengtsson, R Moller, P TI Why the fermion dynamical symmetry model fails to predict nuclear masses: A comprehensive assessment SO PHYSICAL REVIEW C LA English DT Article ID SUPERHEAVY ELEMENTS; FORMULA; HEAVY; ODD AB In the last several years new experimental data have become available on alpha-decay chains starting in the predicted deformed superheavy region near (272)110. This has: promoted new interest in nuclear mass formulas and how well they extrapolate to regions far beyond where experimental masses were previously known. We here focus on two such mass models, namely the fermion dynamical symmetry model and the finite-range droplet model. We have chosen these models since they both reproduce previously known actinide masses with good accuracy, but rapidly diverge from each other in the region of the recently observed new elements. Furthermore, the two models have been the subject of animated discussions concerning which one gives the most reliable predictions of nuclear masses in the superheavy region and in the terminating region of the r process. The new data support the predictions of the finite-range droplet model. We discuss the fermion dynamical symmetry model and its application [Han ct al., Phys. Rev. C 45, 1127 (1992)] to the calculation of trans-Pb nuclear masses. As will be shown, the model contains unphysical features and has many more free constants than claimed. The values obtained for the constants and the model agreement with data in the legion of adjustment are therefore of no particular significance and severe divergences occur for recently discovered nuclei outside the region of adjustment. C1 Lund Inst Technol, Dept Math Phys, Lund, Sweden. Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Bengtsson, R (reprint author), Lund Inst Technol, Dept Math Phys, POB 118, Lund, Sweden. NR 39 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 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD JUL PY 2001 VL 64 IS 1 AR 014308 DI 10.1103/PhysRevC.64.014308 PG 19 WC Physics, Nuclear SC Physics GA 452XB UT WOS:000169884000014 ER PT J AU Brown, DA Danielewicz, P AF Brown, DA Danielewicz, P TI Observing non-Gaussian sources in heavy-ion reactions SO PHYSICAL REVIEW C LA English DT Article ID BOSE-EINSTEIN CORRELATIONS; CERN SPS; PB COLLISIONS; INTERFEROMETRY; DEPENDENCE; DYNAMICS AB We examine the possibility of extracting non-Gaussian sources from two-particle correlations in heavy-ion reactions. Non-Gaussian sources have been predicted in a variety of model calculations and may have been seen in various like-meson pair correlations. As a tool for this investigation, we have developed an improved imaging method that relies on a basis spline expansion of the source functions with an improved implementation of constraints. We examine under what conditions this improved method can distinguish between Gaussian and non-Gaussian sources. Finally, we investigate pion, kaon, and proton sources from the p-Pb reaction at 450 GeV/nucleon and from the S-Pb reaction at 200 GeV/nucleon studied by the NA44 experiment. Both the pion and kaon sources from the S-Pb correlations seem to exhibit a Gaussian core with an extended, non-Gaussian halo. We also find evidence For a scaling of the source widths with particle mass in the sources from the p-Pb reaction. C1 Univ Washington, Seattle, WA 98195 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Michigan State Univ, E Lansing, MI 48824 USA. RP Brown, DA (reprint author), Univ Washington, Seattle, WA 98195 USA. NR 35 TC 46 Z9 48 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 JUL PY 2001 VL 64 IS 1 AR 014902 DI 10.1103/PhysRevC.64.014902 PG 18 WC Physics, Nuclear SC Physics GA 452XB UT WOS:000169884000034 ER PT J AU Browne, E Norman, EB Canaan, RD Glasgow, DC Keller, JM Young, JP AF Browne, E Norman, EB Canaan, RD Glasgow, DC Keller, JM Young, JP TI Search for decay of the 3.5-eV level in Th-229 SO PHYSICAL REVIEW C LA English DT Article ID RESONANT EXCITATION; OPTICAL PHOTONS; EXCITED-STATE; ISOMER; EV); TH-229M(3/2(+); EMISSION; NUCLEUS AB We used a novel radiochemical technique to search for the decay of the 3.5-eV level (Th-229(m)) in Th-229 to the ground state (Th-229(g)) by separating "firesh" Th-229 from approximately 25 g of U-233. We then measured its gamma -ray decay as a function of time seeking evidence of Th-229(g) growth from Th-229(m) isomeric decay. No evidence of such growth was observed. From this experiment we have concluded that the Th-229(m) half-life must be either <6 h or >20 days. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Browne, E (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, 1 Cyclotron Rd, Berkeley, CA 94720 USA. NR 22 TC 16 Z9 16 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 JUL PY 2001 VL 64 IS 1 AR 014311 DI 10.1103/PhysRevC.64.014311 PG 3 WC Physics, Nuclear SC Physics GA 452XB UT WOS:000169884000017 ER PT J AU Chance, JL Brady, FP Romero, JL Albergo, S Bieser, F Caccia, Z Cebra, D Chacon, AD Choi, Y Costa, S Elliott, JB Gilkes, ML Hauger, JA Hirsch, AS Hjort, EL Insolia, A Justice, M Keane, D Kintner, JC Lindenstruth, V Lisa, MA Matis, HS McMahan, M McParland, C Muller, WFJ Olson, DL Partlan, MD Porile, NT Potenza, R Rai, C Rasmussen, JO Ritter, HG Romanski, J Russo, GV Sann, H Scharenberg, R Scott, A Shao, Y Srivastava, BK Symons, TJM Tincknell, M Tuve, C Wang, S Warren, PG Wieman, HH Wienold, T Wolf, K AF Chance, JL Brady, FP Romero, JL Albergo, S Bieser, F Caccia, Z Cebra, D Chacon, AD Choi, Y Costa, S Elliott, JB Gilkes, ML Hauger, JA Hirsch, AS Hjort, EL Insolia, A Justice, M Keane, D Kintner, JC Lindenstruth, V Lisa, MA Matis, HS McMahan, M McParland, C Muller, WFJ Olson, DL Partlan, MD Porile, NT Potenza, R Rai, C Rasmussen, JO Ritter, HG Romanski, J Russo, GV Sann, H Scharenberg, R Scott, A Shao, Y Srivastava, BK Symons, TJM Tincknell, M Tuve, C Wang, S Warren, PG Wieman, HH Wienold, T Wolf, K CA EOS Collaboration TI Mass dependence of the transverse momenta of Au projectile fragments at 1.0A GeV SO PHYSICAL REVIEW C LA English DT Article ID RELATIVISTIC HEAVY-IONS; NUCLEAR SHOCK-WAVES; IONIZATION-CHAMBER; COLLECTIVE FLOW; COLLISIONS; CHARGE; ENERGY; DISTRIBUTIONS; LA-139; MATTER AB The transverse momenta (p(x) ,p(y)) of projectile fragments produced by 1.0A GeV Au-197 nuclei incident on Au and C targets have been measured. The medium and heavy fragments have p(x) and p(y) distributions, which are wider than predicted by models. For the Au target the widths of the distributions are significantly larger than those for C, particularly for the heavy fragments. The C distributions show a different gross structure, which may be due to the target-projectile size difference. C1 Univ Calif Davis, Davis, CA 95616 USA. Univ Catania, I-95129 Catania, Italy. Ist Nazl Fis Nucl, Sez Catania, I-95129 Catania, Italy. Kent State Univ, Kent, OH 44242 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. Purdue Univ, W Lafayette, IN 47907 USA. Texas A&M Univ, College Stn, TX 77843 USA. GSI Darmstadt, D-64220 Darmstadt, Germany. RP Chance, JL (reprint author), Univ Calif Davis, Davis, CA 95616 USA. RI Insolia, Antonio/M-3447-2015; TUVE', Cristina/P-3933-2015 OI Insolia, Antonio/0000-0002-9040-1566; TUVE', Cristina/0000-0003-0739-3153 NR 36 TC 2 Z9 2 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 JUL PY 2001 VL 64 IS 1 AR 014610 DI 10.1103/PhysRevC.64.014610 PG 5 WC Physics, Nuclear SC Physics GA 452XB UT WOS:000169884000032 ER PT J AU Esbensen, H Bertsch, GF AF Esbensen, H Bertsch, GF TI Eikonal approximation in heavy-ion fragmentation reactions SO PHYSICAL REVIEW C LA English DT Article ID REACTION CROSS-SECTIONS; HALO NUCLEI; COULOMB BREAKUP; BE-11; LI-11; MODEL; RADII; B-8 AB Projectile fragmentation reactions are well suited to structure studies of weakly hound nuclei, hut an accurate reaction theory is necessary to extract quantitative spectroscopic properties. We examine here the accuracy of the commonly used eikonal approximation for the nuclear-induced breakup of halo nuclei. Comparing to numerical solutions of the full time-dependent Schrodinger equation, we find that the eikonal remains fairly accurate for calculating breakup probabilities of halo nuclei even down to 20 MeV/nucleon, reproducing relative spectroscopic strengths to within a few percent. Absolute reaction probabilities tend to be underpredicted by the eikonal, which would make extracted spectroscopic strengths somewhat too high. We discuss other features that are seen in the full calculation but are missing in the eikonal approximation such as the "towing" mode. C1 Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. Univ Washington, Inst Nucl Theory, Seattle, WA 98195 USA. RP Esbensen, H (reprint author), Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. NR 24 TC 33 Z9 33 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 JUL PY 2001 VL 64 IS 1 AR 014608 DI 10.1103/PhysRevC.64.014608 PG 6 WC Physics, Nuclear SC Physics GA 452XB UT WOS:000169884000030 ER PT J AU Magas, VK Csernai, LP Strottman, DD AF Magas, VK Csernai, LP Strottman, DD TI Initial state of ultrarelativistic heavy ion collisions SO PHYSICAL REVIEW C LA English DT Article ID RELATIVISTIC NUCLEAR COLLISIONS; STRING FUSION MODEL; QUARK-GLUON PLASMA; FREEZE-OUT MODELS; PB COLLISIONS; COLLECTIVITY; ENERGY; FLOW AB A model for energy, pressure, and flow velocity distributions at the beginning of ultrarelativistic heavy ion collisions is presented, which can be used as an initial condition for hydrodynamic calculations. Our model takes into account baryon recoil for both target and projectile, arising from the acceleration of partons in an effective field F-muv produced in the collision. The typical field strength (string tension) for RHIC energies is about 5-12 GeV/fm, which allows us to talk about "string ropes." The results show that a quark-gluon plasma forms a tilted disk, such that the direction of the largest pressure gradient stays in the reaction plane, hut deviates from both the beam and the usual transverse flow directions. Such initial conditions may lead to the creation of "antiflow'' or ''third flow component''. C1 Univ Bergen, Dept Phys, Sect Theoret & Computat Phys, N-5007 Bergen, Norway. KFKI Res Inst Particle & Nucl Phys, H-1525 Budapest, Hungary. Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87454 USA. Univ Frankfurt, Inst Theoret Phys, D-60054 Frankfurt, Germany. RP Magas, VK (reprint author), Univ Bergen, Dept Phys, Sect Theoret & Computat Phys, Allegaten 55, N-5007 Bergen, Norway. EM VLADIMIR@FL.UIB.NO; CSERNAI@FL.UIB.NO; DDS@LANL.GOV RI Magas, Volodymyr/J-8599-2016 OI Magas, Volodymyr/0000-0003-3701-8362 NR 35 TC 44 Z9 44 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 JUL PY 2001 VL 64 IS 1 AR 014901 DI 10.1103/PhysRevC.64.014901 PG 11 WC Physics, Nuclear SC Physics GA 452XB UT WOS:000169884000033 ER PT J AU Matsuda, Y Bowman, JD Crawford, BE Delheij, PPJ Haseyama, T Knudsen, JN Lowie, LY Masaike, A Masuda, Y Mitchell, GE Penttila, SI Postma, H Roberson, NR Seestrom, SJ Sharapov, EI Stephenson, SL Yen, YF Yuan, VW AF Matsuda, Y Bowman, JD Crawford, BE Delheij, PPJ Haseyama, T Knudsen, JN Lowie, LY Masaike, A Masuda, Y Mitchell, GE Penttila, SI Postma, H Roberson, NR Seestrom, SJ Sharapov, EI Stephenson, SL Yen, YF Yuan, VW TI Parity violation in neutron resonances of antimony and iodine SO PHYSICAL REVIEW C LA English DT Article ID COMPOUND-NUCLEUS; NONCONSERVATION; APPARATUS; CAPTURE; SYSTEM AB Parity violation in p-wave neutron resonances of (121)Sb, (123)Sb, and (127)I has been measured hy transmission of a longitudinally polarized neutron beam through natural antimony and iodine targets. The measurements were performed at the pulsed spallation neutron source of the Los Alamos Neutron Science Center. Five statistically significant parity violation effects were observed in (121)Sb, one effect in (123)Sb, and seven effects in (127)I. The weak interaction rms matrix elements and the corresponding spreading widths were determined. C1 Kyoto Univ, Dept Phys, Kyoto 60601, Japan. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Duke Univ, Durham, NC 27708 USA. Triangle Univ Nucl Lab, Durham, NC 27708 USA. TRIUMF, Vancouver, BC V6T 2A3, Canada. N Carolina State Univ, Raleigh, NC 27695 USA. Natl Lab High Energy Phys, Tsukuba, Ibaraki 305, Japan. Delft Univ Technol, IRI, NL-2629 JB Delft, Netherlands. Joint Inst Nucl Res, RU-141980 Dubna, Russia. RP Matsuda, Y (reprint author), RIKEN, Inst Phys & Chem Res, Wako, Saitama 3510198, Japan. RI Matsuda, Yasuyuki/C-3007-2008 OI Matsuda, Yasuyuki/0000-0002-9847-3791 NR 29 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 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD JUL PY 2001 VL 64 IS 1 AR 015501 DI 10.1103/PhysRevC.64.015501 PG 7 WC Physics, Nuclear SC Physics GA 452XB UT WOS:000169884000038 ER PT J AU Pieper, SC Pandharipande, VR Wiringa, RB Carlson, J AF Pieper, SC Pandharipande, VR Wiringa, RB Carlson, J TI Realistic models of pion-exchange three-nucleon interactions SO PHYSICAL REVIEW C LA English DT Article ID MONTE-CARLO CALCULATIONS; ELASTIC ELECTRON-SCATTERING; 3-NUCLEON FORCE; LIGHT-NUCLEI; ENERGY-LEVELS; POTENTIALS; MATTER; DEUTERON; SYMMETRY; SYSTEMS AB We present realistic models of pion-exchange three-nucleon interactions obtained by fitting the energies of all the 17 bound or narrow states of 3 less than or equal toA less than or equal to8 nucleons, calculated with less than 2% error using the Green's function Monte Carlo method. The models contain two-pion-exchange terms due to piN scattering in S and P waves, three-pion-exchange terms due to ring diagrams with one Delta in the intermediate states, and a phenomenological repulsive term to take into account relativistic effects, the suppression of the two-pion-exchange two-nucleon interaction by the third nucleon, and other effects. The models have five parameters, consisting of the strength of the four interactions and the short-range cutoff. The 17 fitted energies are insufficient to determine all of them uniquely. We consider five models, each having three adjustable parameters and assumed values for the other two. They reproduce the observed energies with an rms error < 1% when used together with the Argonne v(18) two-nucleon interaction. In one of the models the N S-wave scattering interaction is set to zero; in all others it is assumed to have the strength suggested by chiral effective-field theory. One of the models also assumes that the piN P-wave scattering interaction has the strength suggested by effective-held theories, and the cutoff is adjusted to fit the data. In all other models the cutoff is taken to be the same as in the v(18) interaction. The effect of relativistic boost correction to the two-nucleon interaction on the strength of the repulsive three-nucleon interaction is estimated. Many calculated properties of A less than or equal to 8 nuclei, including radii, magnetic dipole, and electric quadrupole moments, isobaric analog energy differences, etc., are tabulated. Results obtained with only Argonne v(8)' and v(18) interactions are also reported, in addition, we present results for seven- and eight-body neutron drops in external potential wells. C1 Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. Univ Illinois, Dept Phys, Urbana, IL 61801 USA. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. EM spieper@anl.gov; vijay@rsml1.physics.uiuc.edu; wiringa@anl.gov; carlson@paths.lanl.gov RI Wiringa, Robert/M-4970-2015 NR 65 TC 408 Z9 412 U1 1 U2 7 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 JUL PY 2001 VL 64 IS 1 AR 014001 DI 10.1103/PhysRevC.64.014001 PG 21 WC Physics, Nuclear SC Physics GA 452XB UT WOS:000169884000006 ER PT J AU Smith, DA Bowman, JD Crawford, BE Grossmann, CA Haseyama, T Johnson, MB Masaike, A Matsuda, Y Mitchell, GE Nazarenko, VA Penttila, SI Roberson, NR Seestrom, SJ Sharapov, EI Smotritsky, LM Stephenson, SL Tomsovic, S Yuan, VW AF Smith, DA Bowman, JD Crawford, BE Grossmann, CA Haseyama, T Johnson, MB Masaike, A Matsuda, Y Mitchell, GE Nazarenko, VA Penttila, SI Roberson, NR Seestrom, SJ Sharapov, EI Smotritsky, LM Stephenson, SL Tomsovic, S Yuan, VW TI Parity violation in neutron resonances of Sn-117 SO PHYSICAL REVIEW C LA English DT Article ID COMPOUND NUCLEUS; NONCONSERVATION; CAPTURE; LA-139; SYSTEM; TH-232; U-238 AB Parity nonconservation (PNC) has been studied in neutron p-wave resonances of Sn-117. The longitudinal asymmetries were measured for 29 p-wave resonances in the neutron energy range 0.8 eV to 1100 eV. Statistically significant PNC effects were observed for four resonances. A statistical analysis determined the rms weak mixing matrix element and the weak spreading width. A weak spreading width of Gamma (w) = (0.28(-0.15)(+0.56))x10(-7) eV was obtained for Sn-117. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Duke Univ, Durham, NC 27708 USA. Triangle Univ Nucl Lab, Durham, NC 27708 USA. N Carolina State Univ, Raleigh, NC 27695 USA. Kyoto Univ, Dept Phys, Kyoto 60601, Japan. Petersburg Nucl Phys Inst, RU-188350 Gatchina, Russia. Joint Inst Nucl Res, RU-141980 Dubna, Russia. Washington State Univ, Dept Phys, Pullman, WA 99164 USA. RP Smith, DA (reprint author), Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RI Matsuda, Yasuyuki/C-3007-2008 OI Matsuda, Yasuyuki/0000-0002-9847-3791 NR 37 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 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD JUL PY 2001 VL 64 IS 1 AR 015502 PG 9 WC Physics, Nuclear SC Physics GA 452XB UT WOS:000169884000039 ER PT J AU Starosta, K Chiara, CJ Fossan, DB Koike, T LaFosse, DR Lane, GJ Sears, JM Smith, JF Boston, AJ Nolan, PJ Paul, ES Semple, AT Devlin, M Sarantites, DG Lee, IY Macchiavelli, AO Ragnarsson, I AF Starosta, K Chiara, CJ Fossan, DB Koike, T LaFosse, DR Lane, GJ Sears, JM Smith, JF Boston, AJ Nolan, PJ Paul, ES Semple, AT Devlin, M Sarantites, DG Lee, IY Macchiavelli, AO Ragnarsson, I TI Smooth band termination at high spin in I-113 SO PHYSICAL REVIEW C LA English DT Article ID GAMMA-RAY SPECTROSCOPY; STATES; NUCLEI AB The I-113 nucleus has been studied using the Ni-58(Ni-58,3p) reaction at 250 MeV with the Gammasphere/ Microball facility. Gamma-ray three- and four-fold data gated by charged particle combinations were analyzed. Multipolarities of the gamma rays were assigned following the angular correlation measurements. The present study is focused on the high spin properties, where the structure is dominated by 2p-2h excitations across the Z=50 gap. Ten decoupled bands showing the features of smooth band termination were observed; three of those bands are linked to known low-spin states, which allows the identification of configurations by direct comparisons with configuration-dependent cranked Nilsson-Strutinsky calculations. The yrast band, which was linked along with the signature partner, was followed up to (101/2(+)) and (h) over bar omega similar to1.3 MeV. The other linked band was a negative-parity band observed up to (95/2(-)). Tentative configurations for the unlinked bands are discussed. Comparisons with the theoretical results suggest that the band built on a configuration involving the neutron i(13/2) intruder orbital originating from the N=6 harmonic oscillator subshell was observed in this experiment. C1 SUNY Stony Brook, Dept Phys & Astron, Stony Brook, NY 11794 USA. Univ Liverpool, Oliver Lodge Lab, Liverpool L69 7ZE, Merseyside, England. Washington Univ, Dept Chem, St Louis, MO 63130 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. Lund Inst Technol, Dept Math Phys, S-22100 Lund, Sweden. RP Starosta, K (reprint author), SUNY Stony Brook, Dept Phys & Astron, Stony Brook, NY 11794 USA. RI Lane, Gregory/A-7570-2011; Devlin, Matthew/B-5089-2013 OI Lane, Gregory/0000-0003-2244-182X; Devlin, Matthew/0000-0002-6948-2154 NR 19 TC 15 Z9 15 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 JUL PY 2001 VL 64 IS 1 AR 014304 DI 10.1103/PhysRevC.64.014304 PG 19 WC Physics, Nuclear SC Physics GA 452XB UT WOS:000169884000010 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 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, F 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 Castila-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 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 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 Frame, KC Fuess, S Gallas, E Galyaev, AN Gao, M Gavrilov, V Genik, RJ Genser, K Gerber, CE Gershtein, Y Gilmartin, R Ginther, 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 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 Kahn, S Kajfasz, E Kalinin, AM Karmanov, D Karmgard, D Kehoe, R Kharchilava, A Kim, SK Klima, B Knuteson, B Ko, W Kohli, JM Kostritskiy, AV Kotcher, J 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 Leflat, A Leggett, C Lehner, F Li, J Li, QZ 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 McDonald, J 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 Piekarz, H Pope, BG Popkov, E Prosper, HB Protopopescu, S Qian, J Raja, R Rajaopalan, S Ramberg, E Rapidis, PA Reay, NW Reucroft, S Rha, J Ridel, M Rijssenbeek, M Rockwell, T Roco, M Rubinov, P Ruchti, R Rutherfoord, J Sabirov, BM 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 Stoyanova, DA Strauss, M Strovink, M Stutte, L Sznajder, A Taylor, W Tentindo-Repond, S Toback, D Tripathi, SM Trippe, TG Turcot, AS Tuts, PM van Gemmeren, P Vaniev, V Van Kooten, R Varelas, N Vertogradov, LS 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 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, F 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 Castila-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 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 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 Frame, KC Fuess, S Gallas, E Galyaev, AN Gao, M Gavrilov, V Genik, RJ Genser, K Gerber, CE Gershtein, Y Gilmartin, R Ginther, 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 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 Kahn, S Kajfasz, E Kalinin, AM Karmanov, D Karmgard, D Kehoe, R Kharchilava, A Kim, SK Klima, B Knuteson, B Ko, W Kohli, JM Kostritskiy, AV Kotcher, J 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 Leflat, A Leggett, C Lehner, F Li, J Li, QZ 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 McDonald, J 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 Piekarz, H Pope, BG Popkov, E Prosper, HB Protopopescu, S Qian, J Raja, R Rajaopalan, S Ramberg, E Rapidis, PA Reay, NW Reucroft, S Rha, J Ridel, M Rijssenbeek, M Rockwell, T Roco, M Rubinov, P Ruchti, R Rutherfoord, J Sabirov, BM 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 Stoyanova, DA Strauss, M Strovink, M Stutte, L Sznajder, A Taylor, W Tentindo-Repond, S Toback, D Tripathi, SM Trippe, TG Turcot, AS Tuts, PM van Gemmeren, P Vaniev, V Van Kooten, R Varelas, N Vertogradov, LS 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 DO Collaboration TI Quasi-model-independent search for new physics at large transverse momentum SO PHYSICAL REVIEW D LA English DT Article ID 2ND-GENERATION LEPTOQUARK PAIRS; DYNAMICAL SYMMETRY BREAKING; PRODUCTION CROSS-SECTION; ROOT-S=1.8 TEV; P(P)OVER-BAR COLLISIONS; (P)OVER-BAR-P COLLISIONS; QUARK COMPOSITENESS; HADRON COLLIDERS; ANOMALOUS WW; Z-BOSONS AB We apply a quasi-model-independent strategy ("SLEUTH") to search for new high p(T) physics in approximate to 100 pb(-1) of p (p) over bar collisions at roots = 1.8 TeV collected by the D empty set experiment during 1992-1996 at thr Fermilab Tevatron. Over 32 e muX, W+jets-like, Z+jets-like, and (ll gamma)(ll gamma)(ll gamma )X exclusive final states are systematically analyzed for hints of physics beyond the standard model. Simultaneous sensitivity to a variety of models predicting new phenomena at the electroweak scale is demonstrated by testing the method on a particular signature in each set of final states. No evidence of new high p(T) physics is observed in the course of this search, and we find that 89% of an ensemble of hypothetical similar experimental runs would have produced a final state with a candidate signal more interesting than the most interesting observed in these data. C1 Joint Nucl Res Inst, 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, Ctr Particle Phys, Inst Phys, Prague, Czech Republic. Univ San Francisco Quito, Quito, Ecuador. Univ Grenoble 1, Inst Sci Nucl, CNRS, IN2P3, Grenoble, France. Univ Mediterranee, CPPM, CNRS, IN2P3, Marseille, France. Univ Paris 06, LPNHE, CNRS, IN2P3, Orsay, France. Univ Paris 07, LPNHE, CNRS, IN2P3, Orsay, France. CEA, DAPNIA, Serv Phys Particles, 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. Univ Amsterdam, NIKHEF, Amsterdam, Netherlands. FOM, Inst NIKHEF, NL-1098 SJ Amsterdam, Netherlands. Univ Nijmegen, NIKHEF, Nijmegen, Netherlands. Inst Phys Nucl, Krakow, Poland. Moscow 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, Berkeley, CA 94720 USA. 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. Fermi 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. Univ Texas, Arlington, TX 76019 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 Nucl Res Inst, Dubna, Russia. RI Kim, Sun Kee/G-2042-2015; Chekulaev, Sergey/O-1145-2015; Sznajder, Andre/L-1621-2016; Canelli, Florencia/O-9693-2016; Belyaev, Alexander/F-6637-2015; Peters, Michael/B-4973-2009; Shivpuri, R K/A-5848-2010; Gutierrez, Phillip/C-1161-2011; Leflat, Alexander/D-7284-2012; Dudko, Lev/D-7127-2012; 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; Santoro, Alberto/E-7932-2014; Juste, Aurelio/I-2531-2015; Grinstein, Sebastian/N-3988-2014; OI 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; Madaras, Ronald/0000-0001-7399-2993; Hedin, David/0000-0001-9984-215X; Wahl, Horst/0000-0002-1345-0401; Belyaev, Alexander/0000-0002-1733-4408; Dudko, Lev/0000-0002-4462-3192; Yip, Kin/0000-0002-8576-4311; Kuleshov, Sergey/0000-0002-3065-326X; De, Kaushik/0000-0002-5647-4489; Beuselinck, Raymond/0000-0003-2613-7446; Hays, Chris/0000-0003-2371-9723; Bassler, Ursula/0000-0002-9041-3057; Filthaut, Frank/0000-0003-3338-2247; 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; Blazey, Gerald/0000-0002-7435-5758; Evans, Harold/0000-0003-2183-3127 NR 43 TC 11 Z9 11 U1 0 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 JUL 1 PY 2001 VL 64 IS 1 AR 012004 DI 10.1103/PhysRevD.64.012004 PG 24 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 448GN UT WOS:000169619300006 ER PT J AU Affolder, T Akimoto, H Akopian, A Albrow, MG Amaral, P Amendolia, SR Amidei, D Anikeev, K Antos, J Apollinari, G Arisawa, T Asakawa, T Ashmanskas, W Azfar, F Azzi-Bacchetta, P Bacchetta, N Bailey, MW 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 Bevensee, B 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 Bruner, N Buckley-Geer, E Budagov, J Budd, HS Burkett, K Busetto, G Byon-Wagner, A Byrum, KL Calafiura, P Campbell, M Carithers, W Carlson, J Carlsmith, D Caskey, W Cassada, J 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 Cronin-Hennessy, D 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 Donati, S Done, J 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 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 Gordon, A 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 Hafen, E 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 Jensen, H 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, SH Kim, YK Kirby, M Kirk, M Kirsch, L Klimenko, S Koehn, P Kongeter, A Kondo, K Konigsberg, J Kordas, K Korn, A Korytov, A Kovacs, E Kroll, J Kruse, M Kuhlmann, SE Kurino, K Kuwabara, T Laasanen, AT Lai, N Lami, S Lammel, S Lamoureux, JI Lancaster, J Lancaster, M Lander, R 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 Nakaya, T Nakano, I Nelson, C Nelson, T Neu, C Neuberger, D Newman-Holmes, C Ngan, CYP Niu, H Nodulman, L Nomerotski, A Oh, SH Ohmoto, T Ohsugi, T Oishi, R Okusawa, T Olsen, J Orejudos, W Pagliarone, C Palmonari, F Paoletti, R Papadimitriou, V Pappas, SP Partos, D Patrick, J Pauletta, G Paulini, M Paus, C 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 Ragan, K Rakitine, A 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 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 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 Taylor, W Tecchio, M Tesarek, R Teng, PK Terashi, K Tether, S Thompson, AS Thurman-Keup, R Tipton, P Tkaczyk, S Tollefson, K Tollestrup, A Toyoda, H Trischuk, W de Troconiz, JF Tseng, J Turini, N Ukegawa, F Vaiciulis, T Valls, J Vejcik, S Velev, G Vidal, R Vilar, R Volobouev, I Vucinic, D Wagner, RG Wagner, RL Wahl, J Wallace, NB Walsh, AM Wang, C Wang, MJ 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 Yagil, A 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 Amendolia, SR Amidei, D Anikeev, K Antos, J Apollinari, G Arisawa, T Asakawa, T Ashmanskas, W Azfar, F Azzi-Bacchetta, P Bacchetta, N Bailey, MW 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 Bevensee, B 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 Bruner, N Buckley-Geer, E Budagov, J Budd, HS Burkett, K Busetto, G Byon-Wagner, A Byrum, KL Calafiura, P Campbell, M Carithers, W Carlson, J Carlsmith, D Caskey, W Cassada, J 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 Cronin-Hennessy, D 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 Donati, S Done, J 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 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 Gordon, A 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 Hafen, E 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 Jensen, H 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, SH Kim, YK Kirby, M Kirk, M Kirsch, L Klimenko, S Koehn, P Kongeter, A Kondo, K Konigsberg, J Kordas, K Korn, A Korytov, A Kovacs, E Kroll, J Kruse, M Kuhlmann, SE Kurino, K Kuwabara, T Laasanen, AT Lai, N Lami, S Lammel, S Lamoureux, JI Lancaster, J Lancaster, M Lander, R 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 Nakaya, T Nakano, I Nelson, C Nelson, T Neu, C Neuberger, D Newman-Holmes, C Ngan, CYP Niu, H Nodulman, L Nomerotski, A Oh, SH Ohmoto, T Ohsugi, T Oishi, R Okusawa, T Olsen, J Orejudos, W Pagliarone, C Palmonari, F Paoletti, R Papadimitriou, V Pappas, SP Partos, D Patrick, J Pauletta, G Paulini, M Paus, C 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 Ragan, K Rakitine, A 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 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 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 Taylor, W Tecchio, M Tesarek, R Teng, PK Terashi, K Tether, S Thompson, AS Thurman-Keup, R Tipton, P Tkaczyk, S Tollefson, K Tollestrup, A Toyoda, H Trischuk, W de Troconiz, JF Tseng, J Turini, N Ukegawa, F Vaiciulis, T Valls, J Vejcik, S Velev, G Vidal, R Vilar, R Volobouev, I Vucinic, D Wagner, RG Wagner, RL Wahl, J Wallace, NB Walsh, AM Wang, C Wang, MJ 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 Yagil, A 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 Measurement of the two-jet differential cross section in p(p)over-bar collisions at root s=1800 GeV SO PHYSICAL REVIEW D LA English DT Article ID (P)OVER-BAR-P COLLISIONS; PARTON DISTRIBUTIONS; PBARP COLLISIONS; GLOBAL ANALYSIS; TEV; EVENTS; PROTON AB A measurement is presented of the two-jet differential cross section d(3)sigma /dE(T)d eta (1)d eta (2) at center of mass energy roots = 1800 GeV in p (p) over bar collisions. The results are based on an integrated luminosity of 86 pb(-1) collected during 1994 to 1995 by the CDF Collaboration at the Fermilab Tevatron collider. The differential cross section is measured as a function of the transverse energy E-T of a jet in the pseudorapidity region 0.1<\ (1)\<0.7 for four different pseudorapidity bins of a second jet restricted to 0.1<\ eta (2) \<3.0. The results are compared with next-to-leading order QCD calculations determined using the CTEQ4 and MRST sets of parton distribution functions. None of the sets ex.amined in this analysis provides a good description of the data. 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, CSIC, Inst Fis Cantabria, E-39005 Santander, Spain. Univ Chicago, Enrico Fermi Inst, Chicago, IL 60637 USA. Joint Nucl Res Inst, 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. KEK, High Energy Accelerator Res Org, Tsukuba, Ibaraki 305, Japan. MIT, Cambridge, MA 02139 USA. McGill Univ, Inst Particle Phys, Montreal, PQ H3A 2T8, Canada. Univ Toronto, Inst Particle Phys, Toronto, ON M5S 1A7, Canada. 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 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 Gorelov, Igor/J-9010-2015; Lancaster, Mark/C-1693-2008; Vucinic, Dejan/C-2406-2008; Nomerotski, Andrei/A-5169-2010; St.Denis, Richard/C-8997-2012; Azzi, Patrizia/H-5404-2012; Punzi, Giovanni/J-4947-2012; Chiarelli, Giorgio/E-8953-2012; Scodellaro, Luca/K-9091-2014; Prokoshin, Fedor/E-2795-2012; Introzzi, Gianluca/K-2497-2015 OI Gorelov, Igor/0000-0001-5570-0133; Azzi, Patrizia/0000-0002-3129-828X; Punzi, Giovanni/0000-0002-8346-9052; Chiarelli, Giorgio/0000-0001-9851-4816; Scodellaro, Luca/0000-0002-4974-8330; Prokoshin, Fedor/0000-0001-6389-5399; Introzzi, Gianluca/0000-0002-1314-2580 NR 16 TC 5 Z9 5 U1 1 U2 5 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 JUL 1 PY 2001 VL 64 IS 1 AR 012001 PG 8 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 448GN UT WOS:000169619300003 ER PT J AU Alavi-Harati, A Alexopoulos, T Arenton, M Arisaka, K Averitte, S Barker, AR 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 Fordyce, PM Glazov, A Golossanov, A Graham, G Graham, J Hagan, K Halkiadakis, E 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 Qiao, C Quinn, B Ramberg, EJ Ray, RE Roodman, A Sadamoto, M Schnetzer, S Senyo, K Shanahan, P Shawhan, PS Slater, W Solomey, N Somalwar, SV Stone, RL Suzuki, I Swallow, EC Taegar, SA Tesarek, RJ Thomson, GB Toale, PA Tripathi, A Tschirhart, R 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 Barker, AR 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 Fordyce, PM Glazov, A Golossanov, A Graham, G Graham, J Hagan, K Halkiadakis, E 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 Qiao, C Quinn, B Ramberg, EJ Ray, RE Roodman, A Sadamoto, M Schnetzer, S Senyo, K Shanahan, P Shawhan, PS Slater, W Solomey, N Somalwar, SV Stone, RL Suzuki, I Swallow, EC Taegar, SA Tesarek, RJ Thomson, GB Toale, PA Tripathi, A Tschirhart, R Wah, YW Wang, J White, HB Whitmore, J Winstein, B Winston, R Yamanaka, T Zimmerman, ED CA KTeV Collaboration TI Measurement of the branching ratio of K-L -> e(+) e(-) gamma gamma SO PHYSICAL REVIEW D LA English DT Article ID DECAY C1 Univ Colorado, Boulder, CO 80309 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. Elmhurst Coll, Elmhurst, IL 60126 USA. Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. Osaka Univ, Toyonaka, Osaka 560, Japan. Rice Univ, Houston, TX 77005 USA. Rutgers State Univ, Piscataway, NJ 08855 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. RP LaDue, J (reprint author), Univ Colorado, Boulder, CO 80309 USA. EM jladue@fnal.gov NR 10 TC 11 Z9 11 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 JUL 1 PY 2001 VL 64 IS 1 AR 012003 DI 10.1103/PhysRevD.64.012003 PG 4 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 448GN UT WOS:000169619300005 ER PT J AU Alton, A Adams, T Bolton, T Goldman, J Goncharov, M Johnson, RA Suwonjandee, N Vakili, M Conrad, J Fleming, BT Formaggio, J Kim, JH Koutsoliotas, S McNulty, C Romosan, A Shaevitz, MH Spentzouris, P Stern, EG Vaitaitis, A Zimmerman, ED 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, J Naples, D Avvakumov, S de Barbaro, P Bodek, A Budd, H Harris, DA McFarland, KS Sakumoto, WK Yang, UK AF Alton, A Adams, T Bolton, T Goldman, J Goncharov, M Johnson, RA Suwonjandee, N Vakili, M Conrad, J Fleming, BT Formaggio, J Kim, JH Koutsoliotas, S McNulty, C Romosan, A Shaevitz, MH Spentzouris, P Stern, EG Vaitaitis, A Zimmerman, ED 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, J Naples, D Avvakumov, S de Barbaro, P Bodek, A Budd, H Harris, DA McFarland, KS Sakumoto, WK Yang, UK TI Observation of neutral current charm production in nu Fe-mu scattering at the Fermilab Tevatron SO PHYSICAL REVIEW D LA English DT Article ID DEEP-INELASTIC SCATTERING; INTRINSIC CHARM; MESON PRODUCTION; PROTON; QUARKS; HERA; MASS AB We report on the first observation of open charm production in neutral current deep inelastic neutrino scattering as seen in the NuTeV detector at Fermilab. The production rate is shown to be consistent with a pure gluon-Z(0) boson production model, and the observed level of charm production is used to determine the effective charm mass. As part of our analysis, we also obtain a new measurement for the proton-nucleon charm production cross section at roots = 38.8 GeV. C1 Kansas State Univ, Manhattan, KS 66506 USA. Univ Cincinnati, Cincinnati, OH 45221 USA. Columbia Univ, New York, NY 10027 USA. Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. Northwestern Univ, Evanston, IL 60208 USA. Univ Oregon, Eugene, OR 97403 USA. Univ Pittsburgh, Pittsburgh, PA 15260 USA. Univ Rochester, Rochester, NY 14627 USA. RP Alton, A (reprint author), Kansas State Univ, Manhattan, KS 66506 USA. RI Frey, Raymond/E-2830-2016 OI Frey, Raymond/0000-0003-0341-2636 NR 32 TC 11 Z9 11 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 JUL 1 PY 2001 VL 64 IS 1 AR 012002 PG 7 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 448GN UT WOS:000169619300004 ER PT J AU Birkedal-Hansen, A Nelson, BD AF Birkedal-Hansen, A Nelson, BD TI Role of W-ino content in neutralino dark matter SO PHYSICAL REVIEW D LA English DT Article ID SUPERSYMMETRY-BREAKING; RELIC DENSITY; MINIMAL SUPERSYMMETRY; GAUGINO CONDENSATION; STAU COANNIHILATION; GRAND-UNIFICATION; SUPERGRAVITY; COSMOLOGY; UNIVERSE; MASSES AB We investigate the dark matter prospects of supersymmetric models with nonuniversal gaugino masses at low values of tan beta. We find that for particular values of the ratio of soft supersymmetry-breaking gaugino masses, M-2/M-1, an enhanced coannihilation efficiency between the lightest chargino and the lightest neutralino occurs. As a specific example, we investigate models of hidden sector gaugino condensation. These models exhibit high scalar masses and the requisite freedom in the ratio of gaugino masses. The cosmologically viable regions of parameter space are investigated, allowing very specific statements to be made about the content of the supersymmetry-breaking hidden sector. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Theoret Phys Grp, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. RP Univ Calif Berkeley, Lawrence Berkeley Lab, Theoret Phys Grp, Berkeley, CA 94720 USA. NR 57 TC 80 Z9 80 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 JUL 1 PY 2001 VL 64 IS 1 AR 015008 DI 10.1103/PhysRevD.64.015008 PG 13 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 448GN UT WOS:000169619300076 ER PT J AU Browning, F Chang, D Keung, WY AF Browning, F Chang, D Keung, WY TI CP asymmetry in the Higgs boson decay into a top quark pair due to top squark mixing SO PHYSICAL REVIEW D LA English DT Article ID MU(+)MU(-) COLLIDERS; STANDARD-MODEL; VIOLATION; PHYSICS; SUPERSYMMETRY AB We investigate a potentially large CP violating asymmetry in the decay of a neutral scalar or pseudoscalar Higgs boson into a t (t) over bar pair. The source of the CP nonconservation is the complex mixing in the top squark (t) over bar (L.R) sector. One of the interesting consequences is the different rates of the Higgs boson decays into CP conjugate polarized states. C1 Univ Illinois, Dept Phys, Chicago, IL 60607 USA. Natl Tsing Hua Univ, NCTS, Hsinchu 30043, Taiwan. Natl Tsing Hua Univ, Dept Phys, Hsinchu 30043, Taiwan. Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Univ Illinois, Dept Phys, Chicago, IL 60607 USA. NR 24 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 JUL 1 PY 2001 VL 64 IS 1 AR 015010 DI 10.1103/PhysRevD.64.015010 PG 8 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 448GN UT WOS:000169619300078 ER PT J AU Czarnecki, A Marciano, WJ AF Czarnecki, A Marciano, WJ TI Muon anomalous magnetic moment: A harbinger for "new physics" SO PHYSICAL REVIEW D LA English DT Review ID SUPERSYMMETRIC STANDARD MODEL; GAUGE-MEDIATED MODEL; HADRONIC CONTRIBUTIONS; ELECTROWEAK CORRECTIONS; G-2 EXPERIMENT; TAU-DECAY; CONSTRAINTS; ALPHA(M-Z(2)); SUPERGRAVITY; (G-2)(MU) AB Standard model loop contributions to the muon anomalous magnetic moment, a(mu) = (g(mu)-2)/2, and their theoretical uncertainties are scrutinized. The status and implications of the recently reported 2.6 sigma experiment versus theory deviation a a(mu)(expt)-a(mu)(SM) = 426(165)x10(-11) are discussed. Possible explanations due to super-symmetric loop effects with m(SUSY)similar or equal to 55(-8)(+16) root tan beta GeV, radiative mass mechanisms at the 1-2 TeV scale and other "new physics" scenarios are examined. C1 Univ Alberta, Dept Phys, Edmonton, AB T6G 2J1, Canada. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Czarnecki, A (reprint author), Univ Alberta, Dept Phys, Edmonton, AB T6G 2J1, Canada. NR 103 TC 309 Z9 311 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 JUL 1 PY 2001 VL 64 IS 1 AR 013014 DI 10.1103/PhysRevD.64.013014 PG 10 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 448GN UT WOS:000169619300022 ER PT J AU El-Khadra, AX Kronfeld, AS Mackenzie, PB Ryan, SM Simone, JN AF El-Khadra, AX Kronfeld, AS Mackenzie, PB Ryan, SM Simone, JN TI Semileptonic decays B ->pi l nu and D ->pi l nu from lattice QCD SO PHYSICAL REVIEW D LA English DT Article ID QUARK EFFECTIVE THEORY; UB-VERTICAL-BAR; V-UB; MASSIVE FERMIONS; GAUGE-THEORY; B-MESONS; HEAVY; CONSTANTS; SPECTRUM; PHYSICS AB We present a lattice QCD calculation of the form factors and differential decay rates for semileptonic decays of the heavy-light mesons B and D to the final state pi/nu. The results are obtained with three methodological improvements over previous lattice calculations: a matching procedure that reduces heavy-quark lattice artifacts, the first study of lattice-spacing dependence, and the introduction of kinematic cuts to reduce model dependence. We show that the main systematics are controllable (within the quenched approximation) and outline how the calculations could be improved to aid current experiments in the determination of \V-ub\ and \V-cd\. C1 Univ Illinois, Dept Phys, Urbana, IL 61801 USA. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Dublin Trinity Coll, Sch Math, Dublin 2, Ireland. RP Univ Illinois, Dept Phys, 1110 W Green St, Urbana, IL 61801 USA. NR 57 TC 79 Z9 79 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 JUL 1 PY 2001 VL 64 IS 1 AR 014502 DI 10.1103/PhysRevD.64.014502 PG 18 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 448GN UT WOS:000169619300063 ER PT J AU Friedland, A AF Friedland, A TI Evolution of the neutrino state inside the Sun SO PHYSICAL REVIEW D LA English DT Article ID EXPONENTIALLY VARYING DENSITY; SOLAR NEUTRINOS; 2-NEUTRINO OSCILLATIONS; VACUUM OSCILLATIONS; ANALYTIC SOLUTION; MATTER; SPECTROSCOPY AB We reexamine the conventional physical description of the neutrino evolution inside the Sun. We point out that the traditional notion of resonance is a useful physical concept only in the limit of small values of the neutrino mixing angle, theta<<1. For large values of theta, the resonance condition specifies neither the point of the maximal violation of adiabaticity in the nonadiabatic case, nor the point where the flavor conversion occurs at the maximal rate in the adiabatic case. The corresponding correct conditions, valid for all values of theta including theta>pi /4, are presented. The adiabaticity condition valid for all values of theta is also described. The results of accurate numerical computations of the level jumping probability in the Sun are presented. These calculations cover a wide range of Deltam(2), from the vacuum oscillation region to the region where the standard exponential approximation is good. A convenient empirical parametrization of these results in terms of elementary functions is given. The matter effects in the so-called ''quasivacuum oscillation regime" are discussed. Finally, it is shown how the known analytical results for the exponential, 1/x, and linear matter distributions can be simply obtained from the formula for the hyperbolic tangent profile. A new expression for the jumping probability for the distribution N(e)proportional to [coth(x/l)+/-1] is obtained. C1 Univ Calif Berkeley, Ernest Orlando Lawrence Berkeley Natl Lab, Theoret Phys Grp, Berkeley, CA 94720 USA. RP Friedland, A (reprint author), Inst Adv Study, Sch Nat Sci, Einstein Dr, Princeton, NJ 08540 USA. NR 39 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 JUL 1 PY 2001 VL 64 IS 1 AR 013008 DI 10.1103/PhysRevD.64.013008 PG 13 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 448GN UT WOS:000169619300016 ER PT J AU Harlander, RV Kilgore, WB AF Harlander, RV Kilgore, WB TI Soft and virtual corrections to pp -> H+X at next-to-next-to-leading order SO PHYSICAL REVIEW D LA English DT Article ID HIGGS-BOSON PRODUCTION; LOW-ENERGY THEOREMS; YAN CROSS-SECTION; PROTON COLLIDERS; QCD CORRECTIONS; 2 LOOPS; LARGE-X; AMPLITUDES; COLLISIONS; BEHAVIOR AB The contributions of virtual corrections and soft gluon emission to the inclusive Higgs boson production cross section pp-->H+X are computed at next-to-next-to-leading order in the heavy top quark limit. We show that this part of the total cross section is well behaved in the sense of perturbative convergence, with the NNLO corrections amounting to an enhancement of the NLO cross section by similar to5% for the CERN LHC and 10-20% for the Fermilab Tevatron. We compare our results with an existing estimate of the full NNLO effects and argue that an analytic evaluation of the hard scattering contributions is needed. C1 Brookhaven Natl Lab, Dept Phys, HET, Upton, NY 11973 USA. RP Harlander, RV (reprint author), Brookhaven Natl Lab, Dept Phys, HET, Upton, NY 11973 USA. EM rharlan@bnl.gov; kilgore@bnl.gov NR 56 TC 154 Z9 154 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 JUL 1 PY 2001 VL 64 IS 1 AR 013015 DI 10.1103/PhysRevD.64.013015 PG 9 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 448GN UT WOS:000169619300023 ER PT J AU Murakami, B Wells, JD AF Murakami, B Wells, JD TI Nucleon scattering with Higgsino and W-ino cold dark matter SO PHYSICAL REVIEW D LA English DT Article ID ANNUAL MODULATION SIGNATURE; SUPERGRAVITY MODELS; STANDARD MODEL; CROSS-SECTION; HALO MODELS; NEUTRALINO; SEARCH; SUPERSYMMETRY; PROTON; PHENOMENOLOGY AB Neutralinos that are mostly W-ino or Higgsino are shown to be compatible with the recent DAMA annual modulation signal. The nucleon scattering rates for these dark matter candidates are typically an order of magnitude above the oft-considered B-ino. Although thermal evolution of Higgsino and W-ino number densities in the early universe implies that they are not viable dark matter candidates, nonthermal sources, such as from gravitino or moduli decay in anomaly-mediated supersymmetry breaking, suggest that they can be the dominant source of cold dark matter. Their stealthiness at high energy colliders gives even more impetus to analyze nucleon scattering detection methods. We also present calculations for their predicted scattering rate with germanium detectors, which have yet to see evidence of WIMP scattering. C1 Univ Calif Davis, Davis Inst High Energy Phys, Davis, CA 95616 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Univ Calif Davis, Davis Inst High Energy Phys, Davis, CA 95616 USA. NR 41 TC 39 Z9 39 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 JUL 1 PY 2001 VL 64 IS 1 AR 015001 DI 10.1103/PhysRevD.64.015001 PG 8 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 448GN UT WOS:000169619300069 ER PT J AU Rizzo, TG AF Rizzo, TG TI Cartography with accelerators: Locating fermions in extra dimensions at future lepton colliders SO PHYSICAL REVIEW D LA English DT Article ID KALUZA-KLEIN EXCITATIONS; SUPERSYMMETRY BREAKING; LOCALIZED GRAVITY; STANDARD MODEL; PHYSICS; HIERARCHY; ORBIFOLDS; PROBES; BOSONS; BOUNDS AB In the model of Arkani-Hamed and Schmaltz the various chiral fermions of the standard model are localized at different points on a thick wall which forms an extra dimension. Such a scenario provides a way of understanding the absence of proton decay and the fermion mass hierarchy in models with extra dimensions. In this paper we explore the capability of future lepton colliders to determine the location of these fermions in the extra dimension through precision measurements of conventional scattering processes both below and on top of the lowest lying Kaluza-Klein gauge boson resonance. We show that for some classes of models the locations of these fermions can be very precisely determined while in others only their relative positions can be well measured. C1 Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. NR 44 TC 24 Z9 24 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 JUL 1 PY 2001 VL 64 IS 1 AR 015003 DI 10.1103/PhysRevD.64.015003 PG 10 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 448GN UT WOS:000169619300071 ER PT J AU Splittorff, K Son, DT Stephanov, MA AF Splittorff, K Son, DT Stephanov, MA TI QCD-like theories at finite baryon and isospin density SO PHYSICAL REVIEW D LA English DT Article ID QUARK MATTER; SUPERCONDUCTIVITY; INEQUALITIES AB We use two-color QCD as a model to study the effects of the simultaneous presence of chemical potentials for isospin charge mu (I) and for baryon number mu (B). We determine the phase diagrams for two and four flavor theories using the method of effective chiral Lagrangians at low densities and weak-coupling perturbation theory at high densities. We determine the values of various condensates and densities as well as the spectrum of excitations as functions of mu (I) and mu (B). A Similar analysis of QCD with quarks in the adjoint representation is also presented. Our results can be of relevance for lattice simulations of these theories. We predict a phase of inhomogeneous condensation (Fulde-Ferrel-Larkin-Ovchinnikov phase) in the two color, two flavor theory, while we do not expect it in the four flavor case or in other realizations of QCD with a positive measure. C1 Niels Bohr Inst, DK-2100 Copenhagen O, Denmark. Columbia Univ, Dept Phys, New York, NY 10027 USA. Brookhaven Natl Lab, RIKEN BNL Res Ctr, Upton, NY 11973 USA. Univ Illinois, Dept Phys, Chicago, IL 60607 USA. RP Niels Bohr Inst, Blegdamsvej 17, DK-2100 Copenhagen O, Denmark. NR 32 TC 94 Z9 94 U1 1 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 JUL 1 PY 2001 VL 64 IS 1 AR 016003 DI 10.1103/PhysRevD.64.016003 PG 10 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 448GN UT WOS:000169619300082 ER PT J AU Wang, YF Balic, V Gratta, G Fasso, A Roesler, S Ferrari, A AF Wang, YF Balic, V Gratta, G Fasso, A Roesler, S Ferrari, A TI Predicting neutron production from cosmic-ray muons SO PHYSICAL REVIEW D LA English DT Article ID SHALLOW DEPTH; SEARCH; PION AB Fast neutrons from cosmic-ray muons are an important background to underground low-energy experiments. The estimate of such a background is often hampered by the difficulty of measuring and calculating neutron production with sufficient accuracy. Indeed substantial disagreement exists between the different analytical calculations performed so far, while data reported by different experiments are not always consistent. We discuss a new unified approach to estimate the neutron yield, the energy spectrum, the multiplicity, and the angular distribution from cosmic muons using the Monte Carlo simulation package FLUKA and show that it gives a good description of most of the existing measurements once the appropriate corrections have been applied. C1 Stanford Univ, Dept Phys, Stanford, CA 94305 USA. Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. Ist Nazl Fis Nucl, Sez Milano, I-20133 Milan, Italy. RP Wang, YF (reprint author), Stanford Univ, Dept Phys, Stanford, CA 94305 USA. NR 29 TC 68 Z9 68 U1 0 U2 3 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD JUL 1 PY 2001 VL 64 IS 1 AR 013012 DI 10.1103/PhysRevD.64.013012 PG 6 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 448GN UT WOS:000169619300020 ER PT J AU Ang, LK Kwan, TJT Lau, YY AF Ang, LK Kwan, TJT Lau, YY TI Limiting current density in a crossed-field nanogap SO PHYSICAL REVIEW E LA English DT Article ID FABRICATION; ARRAYS AB Using a mean-field theory, we have studied the quantum extension on the limiting current density in a crossed-field nanogap. When the gap spacing is less than the electron wavelength, our results show that the limiting current density is increased by a large factor from the classical values due to the effects of electron tunneling. The effects of the external magnetic field diminish with a decrease of gap spacing. Smooth transition from the classical regime to the quantum regime is demonstrated. C1 Univ Calif Los Alamos Natl Lab, Div Appl Phys, Los Alamos, NM 87545 USA. Univ Michigan, Dept Nucl Engn & Radiol Sci, Ann Arbor, MI 48109 USA. RP Ang, LK (reprint author), Univ Calif Los Alamos Natl Lab, Div Appl Phys, POB 1663, Los Alamos, NM 87545 USA. RI ANG, Lay Kee/F-8115-2015 OI ANG, Lay Kee/0000-0003-2811-1194 NR 16 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 1063-651X J9 PHYS REV E JI Phys. Rev. E PD JUL PY 2001 VL 64 IS 1 AR 017501 DI 10.1103/PhysRevE.64.017501 PN 2 PG 4 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 453GC UT WOS:000169907300132 PM 11461446 ER PT J AU Berryman, JG Wang, HF AF Berryman, JG Wang, HF TI Dispersion in poroelastic systems SO PHYSICAL REVIEW E LA English DT Article ID SATURATED POROUS-MEDIA; LONG-WAVELENGTH PROPAGATION; ELASTIC-WAVE-PROPAGATION; ANISOTROPIC POROELASTICITY; FLUID; EQUATIONS; PERMEABILITY; ATTENUATION; INCLUSIONS; POROSITY AB We address one key source of the known discrepancies between theory and experiment in poroelasticity, i.e,, the fact that Gassmann's equations for the bulk and shear moduli predict that the shear modulus is independent of the saturating fluid properties, whereas it is observed on the contrary that at high enough frequencies the shear modulus can in fact depend on the fluid's elastic properties in many porous materials. One clue to understanding this behavior comes from effective medium theory, which shows that the shear modulus does depend on the fluid properties in many circumstances. In comparison to values predicted by effective medium theory, Gassmann's equations predict different, smaller values for both the effective bulk and shear moduli of porous media. Sorting through these apparent (but not actual) disagreements among theory and theory, and theory and experiment is the main thrust of the paper. C1 Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Univ Wisconsin, Dept Geol & Geophys, Madison, WI 53706 USA. RP Lawrence Livermore Natl Lab, POB 808,L-200, Livermore, CA 94551 USA. RI Berryman, James/A-9712-2008 NR 66 TC 21 Z9 22 U1 1 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 JUL PY 2001 VL 64 IS 1 AR 011303 DI 10.1103/PhysRevE.64.011303 PN 1 PG 16 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 453GA UT WOS:000169907100038 PM 11461245 ER PT J AU Dodin, IY Fisch, NJ AF Dodin, IY Fisch, NJ TI Motion of charged particles near magnetic-field discontinuities SO PHYSICAL REVIEW E LA English DT Article ID GUIDING CENTER MOTION; EQUATIONS AB Charged particles near discontinuities in magnetic fields, so-called "boundary particles," can be constrained to remain near the discontinuity, even an arbitrarily fractured discontinuity, as the particle drifts along the fractured boundary. These particles are shown to exhibit new and interesting effects along broken and branching surfaces, including the wetting of fractured surfaces. C1 Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Dodin, IY (reprint author), Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 19 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 1063-651X J9 PHYS REV E JI Phys. Rev. E PD JUL PY 2001 VL 64 IS 1 AR 016405 PN 2 PG 4 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 453GC UT WOS:000169907300094 ER PT J AU Hartemann, FV Baldis, HA Kerman, AK Le Foll, A Luhmann, NC Rupp, B AF Hartemann, FV Baldis, HA Kerman, AK Le Foll, A Luhmann, NC Rupp, B TI Three-dimensional theory of emittance in Compton scattering and x-ray protein crystallography SO PHYSICAL REVIEW E LA English DT Article ID 90-DEGREES THOMSON SCATTERING; INTENSE LASER-PULSES; FREE-ELECTRON LASER; SYNCHROTRON-RADIATION; STRUCTURAL DYNAMICS; DIFFRACTION; VACUUM; DESIGN; BEAMS AB A complete, three-dimensional theory of Compton scattering is described, which fully takes into account the effects of the electron beam emittance and energy spread upon the scattered x-ray spectral brightness. The radiation scattered by an electron subjected to an arbitrary electromagnetic field distribution in vacuum is first derived in the linear regime, and in the absence of radiative corrections; it is found that each vacuum eigenmode gives rise to a single Doppler-shifted classical dipole excitation. This formalism is then applied to Compton scattering in a three-dimensional laser focus, and yields a complete description of the influence of the electron beam phase-space topology on the x-ray spectral brightness; analytical expressions including the effects of emittance and energy spread are also obtained in the one-dimensional Limit. Within this framework, the x-ray brightness generated by a 25 MeV electron beam is modeled, fully taking into account the beam emittance and energy spread, as well as the three-dimensional nature of the laser focus; its application to x-ray protein crystallography is outlined. Finally, coherence, harmonics, and radiative corrections are also briefly discussed. C1 Univ Calif Lawrence Livermore Natl Lab, Inst Laser Sci & Applicat, Livermore, CA 94550 USA. Univ Calif Davis, Dept Appl Sci, Davis, CA 95616 USA. MIT, Ctr Theoret Phys, Cambridge, MA 02139 USA. MIT, Dept Phys, Cambridge, MA 02139 USA. Univ Calif Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, Livermore, CA 94550 USA. Ecole Polytech, F-91128 Palaiseau, France. RP Hartemann, FV (reprint author), Univ Calif Lawrence Livermore Natl Lab, Inst Laser Sci & Applicat, Livermore, CA 94550 USA. NR 69 TC 39 Z9 42 U1 0 U2 2 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 JUL PY 2001 VL 64 IS 1 AR 016501 DI 10.1103/PhysRevE.64.016501 PN 2 PG 26 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 453GC UT WOS:000169907300106 PM 11461420 ER PT J AU Joshi, RP Hu, Q Aly, R Schoenbach, KH Hjalmarson, HP AF Joshi, RP Hu, Q Aly, R Schoenbach, KH Hjalmarson, HP TI Self-consistent simulations of electroporation dynamics in biological cells subjected to ultrashort electrical pulses SO PHYSICAL REVIEW E LA English DT Article ID PLANAR BILAYER-MEMBRANES; LIPID-MEMBRANES; BROWNIAN DYNAMICS; ION PORES; BREAKDOWN; POTENTIALS; CHANNEL; FIELDS; ELECTROPERMEABILIZATION; CONDUCTANCE AB The temporal dynamics of electroporation of cells subjected to ultrashort voltage pulses are studied based on a coupled scheme involving the Laplace, Nernst-Plank. and Smoluchowski equations. A pore radius dependent energy barrier for ionic transport, accounts for cellular variations. It is shown that a finite time delay exists in pore formation, and leads to a transient overshoot of the transmembrane potential V-mem beyond 1.0 V. Pore resealing is shown to consist of an initial fast process, a 10(-4) s delay, followed by a much slower closing at a time constant of about 10(-1) s. This establishes a time-window during which the pores are mostly open, and hence, the system is most vulnerable to destruction by a second electric pulse. The existence of such a time window for effective killing by a second pulse is amply supported by our experimental data for E. coli cells. The time constant for the longer process also matches experiments. The study suggests that controlled manipulation of the pore "open times" can be achieved through multiple, ultrashort pulses. C1 Old Dominion Univ, Dept Elect & Comp Engn, Norfolk, VA 23529 USA. Sandia Natl Labs, Computat Biol & Mat Technol Dept, Albuquerque, NM 87185 USA. RP Old Dominion Univ, Dept Elect & Comp Engn, Norfolk, VA 23529 USA. NR 55 TC 45 Z9 48 U1 1 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 JUL PY 2001 VL 64 IS 1 AR 011913 DI 10.1103/PhysRevE.64.011913 PN 1 PG 10 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 453GA UT WOS:000169907100087 PM 11461294 ER PT J AU Kechagia, P Yortsos, YC Lichtner, P AF Kechagia, P Yortsos, YC Lichtner, P TI Nonlocal Kardar-Parisi-Zhang equation to model interface growth SO PHYSICAL REVIEW E LA English DT Article ID POROUS-MEDIA; GROWING INTERFACES; POLE DECOMPOSITION; FLAME FRONTS; EDEN MODEL; SURFACE; STABILITY; INSTABILITIES; DISPLACEMENT; PROPAGATION AB The dynamics of the growth of interfaces in the presence of noise and when the normal velocity is constant, in the weakly nonlinear limit, are described by the Kardar-Parisi-Zhang (KPZ) equation. In many applications, however, the growth is controlled by nonlocal transport, which is not contained in the original KPZ equation. For these problems we are proposing an extension of the KPZ model, where the nonlocal contribution is expressed through a Hilbert transform and can act to either stabilize or destabilize the interface. The model is illustrated with a specific example from reactive infiltration. The properties of the solution of the resulting equation are studied in one spatial dimension in the linear and the nonlinear limits, for both stable and unstable growth. We find that the early-time behavior has a power-law scaling similar to that of the KPZ equation. However, in the case of stable growth, the scaling of the. saturation width is logarithmic, which differs from the power law in the KPZ equation. This dependence reflects the stabilizing effect of nonlocal transport. Tn the unstable case, we obtain results similar to those of Olami et al. [Phys. Rev. E 55, 2649 (1997)]. C1 Univ So Calif, Dept Chem Engn, Los Angeles, CA 90089 USA. Univ Calif Los Alamos Natl Lab, Div Earth & Environm Sci, Los Alamos, NM 87545 USA. RP Kechagia, P (reprint author), Univ So Calif, Dept Chem Engn, Los Angeles, CA 90089 USA. NR 34 TC 9 Z9 9 U1 0 U2 3 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 JUL PY 2001 VL 64 IS 1 AR 016315 DI 10.1103/PhysRevE.64.016315 PN 2 PG 15 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 453GC UT WOS:000169907300085 PM 11461399 ER PT J AU Wallace, DC Chisolm, ED Clements, BE AF Wallace, DC Chisolm, ED Clements, BE TI Observation of single transits in supercooled monatomic liquids SO PHYSICAL REVIEW E LA English DT Article ID DYNAMICS THEORY; STRUCTURAL TRANSITIONS; MOLECULAR-DYNAMICS; SELF-DIFFUSION; MODEL GLASS; STATE; ELEMENTS AB A transit is the motion of a system from one many-particle potential energy valley to another. We report the observation of transits in molecular dynamics calculations of supercooled liquid argon and sodium. Each transit is a correlated simultaneous shift in the equilibrium positions of a small local group of particles, as revealed in the fluctuating graphs of the particle coordinates versus time. To the best of our knowledge, this is the first reported direct observation of transit motion in a monatomic liquid in thermal equilibrium. We found transits involving 2-11 particles, having mean shift in equilibrium position on the order of 0.4R(1) in argon and 0.25R(1) in sodium, where R-1 is the nearest neighbor distance. The time it takes for a transit to occur is approximately one mean vibrational period. confirming that transits are fast. C1 Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Wallace, DC (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. NR 28 TC 5 Z9 5 U1 1 U2 1 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 JUL PY 2001 VL 64 IS 1 AR 011205 DI 10.1103/PhysRevE.64.011205 PN 1 PG 6 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 453GA UT WOS:000169907100031 PM 11461238 ER PT J AU Borland, M AF Borland, M TI Design and performance simulations of the bunch compressor for the advanced photon source low-energy undulator test line free-electron laser SO PHYSICAL REVIEW SPECIAL TOPICS-ACCELERATORS AND BEAMS LA English DT Article AB A magnetic bunch compressor was designed and commissioned to provide higher peak current for the Advanced Photon Source's Low-Energy Undulator Test Line free-electron laser [S. V. Milton et al., Phys. Rev. Lett. 85, 988 (2000)]. Of great concern is limiting emittance growth due to coherent synchrotron radiation. Tolerances must also be carefully evaluated to find stable operating conditions and ensure that the system can meet operational goals. Automated matching and tolerance simulations allowed consideration of numerous configurations, pinpointing those with reduced error sensitivity. Simulations indicate significant emittance growth up to 600 A peak current, for which the normalized emittance will increase from 5 to about 8.5 mum. The simulations also provide predictions of emittance variation with chicane parameters and precompressor linac phase, which we hope to verify experimentally. C1 Argonne Natl Lab, Argonne, IL 60439 USA. RP Borland, M (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 12 TC 6 Z9 6 U1 0 U2 1 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 JUL PY 2001 VL 4 IS 7 AR 074201 DI 10.1103/PhysRevSTAB.4.074201 PG 6 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 461MX UT WOS:000170369000005 ER PT J AU Borland, M AF Borland, M TI Simple method for particle tracking with coherent synchrotron radiation SO PHYSICAL REVIEW SPECIAL TOPICS-ACCELERATORS AND BEAMS LA English DT Article AB Coherent synchrotron radiation (CSR) is of great interest to those designing accelerators as drivers for free-electron lasers (FELs). Although experimental evidence is incomplete, CSR is predicted to have potentially severe effects on the emittance of high-brightness electron beams. The performance of an FEL depends critically on the emittance, current, and energy spread of the beam. Attempts to increase the current through magnetic bunch compression can lead to increased emittance and energy spread due to CSR in the dipoles of such a compressor. The code ELEGANT was used for design and simulation of the bunch compressor [M. Borland et al., in Proceedings of the 2000 Linear Accelerator Conference, Monterey, CA (SLAC, Menlo Park, CA, 2001), p. 863] for the low-energy undulator test line (LEUTL) FEL [S. V. Milton et al., Phys. Rev. Let. 85, 988 (1999)] at the Advanced Photon Source (APS). In order to facilitate this design, a fast algorithm was developed based on the 1D formalism of Saldin and co-workers [E. L. Saldin, E. A. Schneidmiller, and M. V. Yurkov, Nucl. Instrum. Methods Phys. Res., Sect. A 398, 373 (1997)]. In addition, a method of including CSR effects in drift spaces following the chicane magnets was developed and implemented. The algorithm is fast enough to permit running hundreds of tolerance simulations including CSR for 50 000 particles. This article describes the details of the implementation and shows results for the APS bunch compressor. C1 Argonne Natl Lab, Argonne, IL 60439 USA. RP Borland, M (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 15 TC 55 Z9 55 U1 0 U2 4 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 JUL PY 2001 VL 4 IS 7 AR 070701 DI 10.1103/PhysRevSTAB.4.070701 PG 8 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 461MX UT WOS:000170369000002 ER PT J AU Sze, H Coleman, PL Banister, J Failor, BH Fisher, A Levine, JS Song, Y Waisman, EM Apruzese, JP Clark, RW Davis, J Mosher, D Thornhill, JW Velikovich, AL Weber, BV Coverdale, CA Deeney, C Gilliland, TL McGurn, J Spielman, RB Struve, KW Stygar, WA Bell, D AF Sze, H Coleman, PL Banister, J Failor, BH Fisher, A Levine, JS Song, Y Waisman, EM Apruzese, JP Clark, RW Davis, J Mosher, D Thornhill, JW Velikovich, AL Weber, BV Coverdale, CA Deeney, C Gilliland, TL McGurn, J Spielman, RB Struve, KW Stygar, WA Bell, D TI Efficient argon K-shell radiation from a Z pinch at currents > 15 MA SO PHYSICS OF PLASMAS LA English DT Article ID RAYLEIGH-TAYLOR INSTABILITY; GAS-PUFF; HIGH-VELOCITY; IMPLOSIONS; LOAD AB The first observations of gaseous load implosions with over 15 MA in > 110 ns on the Z generator [R. B. Spielman , Phys. Plasmas 5, 2105 (1998)] are reported. Starting from a diameter of over 8 cm, an argon double-shell Z pinch imploded to under 0.5 cm K-shell emission diameter. With a load mass of 0.8 mg/cm, K-shell x-ray output reached 274 +/- 24 kJ in a 15 TW peak power, 12 ns pulse. This record-high yield is consistent with the current-squared scaling predicted for the "efficient" emission regime. (C) 2001 American Institute of Physics. C1 Titan Corp, Div Pulse Sci, San Leandro, CA 94577 USA. USN, Res Lab, Div Plasma Phys, Washington, DC 20375 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. Def Threat Reduct Agcy, Alexandria, VA 22310 USA. RP Sze, H (reprint author), Titan Corp, Div Pulse Sci, 2700 Merced St, San Leandro, CA 94577 USA. EM plcoleman@mailaps.org RI Velikovich, Alexander/B-1113-2009 NR 20 TC 61 Z9 63 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 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD JUL PY 2001 VL 8 IS 7 BP 3135 EP 3138 DI 10.1063/1.1373418 PG 4 WC Physics, Fluids & Plasmas SC Physics GA 446RG UT WOS:000169525800001 ER PT J AU Kolesnichenko, YI Marchenko, VS White, RB AF Kolesnichenko, YI Marchenko, VS White, RB TI Low frequency fishbone mode induced by circulating particles in spherical tori SO PHYSICS OF PLASMAS LA English DT Article ID INTERNAL KINK; OSCILLATIONS; TOKAMAKS; PLASMAS; IONS AB It is found that high beta in low-aspect-ratio tori tends to stabilize the fishbone instability in a plasma with energetic circulating ions. The stabilization results from enhancement of the toroidal drift motion by large Shafranov shift, which makes it difficult to reconcile the condition of considerable energy exchange between the ions and the internal kink perturbation with the condition of the resonant wave-particle interaction. (C) 2001 American Institute of Physics. C1 Inst Nucl Res, Ctr Sci, UA-03680 Kiev, Ukraine. Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Kolesnichenko, YI (reprint author), Inst Nucl Res, Ctr Sci, UA-03680 Kiev, Ukraine. RI White, Roscoe/D-1773-2013 OI White, Roscoe/0000-0002-4239-2685 NR 15 TC 10 Z9 10 U1 0 U2 3 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD JUL PY 2001 VL 8 IS 7 BP 3143 EP 3145 DI 10.1063/1.1379340 PG 3 WC Physics, Fluids & Plasmas SC Physics GA 446RG UT WOS:000169525800003 ER PT J AU Snyder, PB Hammett, GW AF Snyder, PB Hammett, GW TI A Landau fluid model for electromagnetic plasma microturbulence SO PHYSICS OF PLASMAS LA English DT Article ID ION-TEMPERATURE-GRADIENT; LINEAR GYROKINETIC EQUATIONS; DRIFT ALFVEN TURBULENCE; DRIVEN TURBULENCE; PARTICLE SIMULATION; TOKAMAK TURBULENCE; TOROIDAL GEOMETRY; BALLOONING MODES; KINETIC-THEORY; MAGNETOHYDRODYNAMICS AB A fluid model is developed for the description of microturbulence and transport in magnetized, long mean-free-path plasmas. The model incorporates both electrostatic and magnetic fluctuations, as well as finite Larmor radius and kinetic effects. Multispecies Landau fluid equations are derived from moments of the electromagnetic gyrokinetic equation, using fluid closures which model kinetic effects. A reduced description of electron dynamics, appropriate for the study of microturbulence on characteristic ion drift and Alfven scales, is derived via an expansion in the electron to ion mass ratio. The reduced electron equations incorporate curvature, delB, and linear and nonlinear ExB drift effects, needed to model the electron contribution to the drive and damping of ion gyroradius scale instabilities in tokamaks. The Landau fluid model is linearly benchmarked against gyrokinetic codes, and found to reproduce the toroidal finite beta ion temperature gradient and kinetic ballooning instabilities. (C) 2001 American Institute of Physics. C1 Gen Atom Co, San Diego, CA 92186 USA. Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Snyder, PB (reprint author), Gen Atom Co, POB 85608, San Diego, CA 92186 USA. RI Hammett, Gregory/D-1365-2011 OI Hammett, Gregory/0000-0003-1495-6647 NR 57 TC 57 Z9 58 U1 3 U2 7 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD JUL PY 2001 VL 8 IS 7 BP 3199 EP 3216 DI 10.1063/1.1374238 PG 18 WC Physics, Fluids & Plasmas SC Physics GA 446RG UT WOS:000169525800011 ER PT J AU Hicks, HR Carreras, BA AF Hicks, HR Carreras, BA TI Quasicoherent fluctuations associated with a transport barrier in the sandpile model SO PHYSICS OF PLASMAS LA English DT Article ID SELF-ORGANIZED CRITICALITY; TURBULENT TRANSPORT; SHEARED FLOW; CONFINEMENT; DYNAMICS; PLASMA; AVALANCHES AB A transport barrier is introduced in the one-dimensional sandpile model by reducing the local flux in a barrier region. This reduction causes a modification in the structure of the avalanches and triggers quasiperiodic fluctuations of the particle fluxes. The frequency of these fluctuations is inversely proportional to the transport barrier width. (C) 2001 American Institute of Physics. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37830 USA. RP Hicks, HR (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37830 USA. NR 17 TC 8 Z9 8 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD JUL PY 2001 VL 8 IS 7 BP 3277 EP 3281 DI 10.1063/1.1377295 PG 5 WC Physics, Fluids & Plasmas SC Physics GA 446RG UT WOS:000169525800018 ER PT J AU Leboeuf, JN Lynch, VE Carreras, BA AF Leboeuf, JN Lynch, VE Carreras, BA TI Linear and nonlinear resistive magnetohydrodynamic stability of tokamak discharges with negative central shear SO PHYSICS OF PLASMAS LA English DT Article ID REVERSED MAGNETIC SHEAR; DIII-D TOKAMAK; TOROIDAL GEOMETRY; CONFINEMENT; MODES; PERFORMANCE; TURBULENCE; PROFILES AB Linear and nonlinear magnetohydrodynamic (MHD) calculations have been performed to study the stability of tokamak discharges with reversed or negative central magnetic shear using the finite aspect ratio (FAR) suite of MHD codes [Charlton , J. Comput. Phys. 86, 270 (1990)]. The linear calculations confirm anew that radially localized resistive interchange modes can be unstable in the reversed or negative central magnetic shear region. The calculations further show that these resistive interchange modes are more unstable for toroidal mode numbers n higher than n=1. The nonlinear calculations do however demonstrate that toroidal mode number n=1, enhanced by the nonlinear couplings of the linearly more unstable higher n toroidal harmonics, dominates the nonlinearly saturated steady state. While the resistive interchange modes may account for the precursors detected experimentally, the saturated levels of magnetic fluctuations obtained in the nonlinear calculations do not appear large enough to cause the experimentally observed global collapse of such discharges. (C) 2001 American Institute of Physics. C1 Univ Calif Los Angeles, Los Angeles, CA 90095 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Leboeuf, JN (reprint author), Univ Calif Los Angeles, Los Angeles, CA 90095 USA. RI Lynch, Vickie/J-4647-2012 OI Lynch, Vickie/0000-0002-5836-7636 NR 29 TC 7 Z9 7 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD JUL PY 2001 VL 8 IS 7 BP 3358 EP 3366 DI 10.1063/1.1376651 PG 9 WC Physics, Fluids & Plasmas SC Physics GA 446RG UT WOS:000169525800027 ER PT J AU Hudson, SR Monticello, DA Reiman, AH AF Hudson, SR Monticello, DA Reiman, AH TI Reduction of islands in full-pressure stellarator equilibria SO PHYSICS OF PLASMAS LA English DT Article AB The control of magnetic islands is a crucial issue in designing stellarators. Islands are associated with resonant radial magnetic fields at rational rotational-transform surfaces and can lead to chaos and poor plasma confinement. In this article it is shown that variations in the resonant fields of a full pressure stellarator equilibrium can be related to variations in the boundary via a coupling matrix, and that inversion of this matrix determines a boundary modification for which the island content is significantly reduced. The numerical procedure is described and the results of island optimization are presented. Equilibria with islands are computed using the Princeton Iterative Equilibrium Solver, and resonant radial fields are calculated via construction of quadratic-flux-minimizing surfaces. A design candidate for the National Compact Stellarator Experiment [A. Reimann, L. Ku, D. Monticello , Phys. Plasmas 8, 2083 (2001)], which has a large island, is used to illustrate the technique. Small variations in the boundary shape are used to reduce island size and to reverse the phase of a major island chain. (C) 2001 American Institute of Physics. C1 Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Hudson, SR (reprint author), Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. RI Hudson, Stuart/H-7186-2013 OI Hudson, Stuart/0000-0003-1530-2733 NR 13 TC 15 Z9 15 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD JUL PY 2001 VL 8 IS 7 BP 3377 EP 3381 DI 10.1063/1.1377614 PG 5 WC Physics, Fluids & Plasmas SC Physics GA 446RG UT WOS:000169525800029 ER PT J AU Carolipio, EM Heidbrink, WW Cheng, CZ Chu, MS Fu, GY Jaun, A Spong, DA Turnbull, AD White, RB AF Carolipio, EM Heidbrink, WW Cheng, CZ Chu, MS Fu, GY Jaun, A Spong, DA Turnbull, AD White, RB TI The toroidicity-induced Alfven eigenmode structure in DIII-D: Implications of soft x-ray and beam-ion loss data SO PHYSICS OF PLASMAS LA English DT Article ID JOINT EUROPEAN TORUS; ENERGETIC PARTICLE-TRANSPORT; DEUTERIUM-TRITIUM PLASMAS; FUSION TEST REACTOR; NEUTRAL BEAM; D TOKAMAK; DRIVEN INSTABILITIES; MODES; STABILITY; TFTR AB The internal structure of the toroidicity-induced Alfven eigenmode (TAE) is studied by comparing soft x-ray profile and beam ion loss data taken during TAE activity in the DIII-D tokamak [W. W. Heidbrink , Nucl. Fusion 37, 1411 (1997)] with predictions from theories based on ideal magnetohydrodynamic (MHD), gyrofluid, and gyrokinetic models. The soft x-ray measurements indicate a centrally peaked eigenfunction, a feature which is closest to the gyrokinetic model's prediction. The beam ion losses are simulated using a guiding center code. In the simulations, the TAE eigenfunction calculated using the ideal MHD model acts as a perturbation to the equilibrium field. The predicted beam ion losses are an order of magnitude less than the observed similar to6%-8% losses at the peak experimental amplitude of deltaB(r)/B(0)similar or equal to2-5x10(-4). (C) 2001 American Institute of Physics. C1 Univ Calif Irvine, Dept Phys & Astron, Irvine, CA 92697 USA. Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08544 USA. Gen Atom Co, San Diego, CA 92186 USA. Royal Inst Technol, Alfven Lab, Stockholm, Sweden. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Carolipio, EM (reprint author), Univ Calif Irvine, Dept Phys & Astron, Irvine, CA 92697 USA. RI Spong, Donald/C-6887-2012; White, Roscoe/D-1773-2013; Cheng, Chio/K-1005-2014 OI Spong, Donald/0000-0003-2370-1873; White, Roscoe/0000-0002-4239-2685; NR 64 TC 27 Z9 28 U1 1 U2 5 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD JUL PY 2001 VL 8 IS 7 BP 3391 EP 3401 DI 10.1063/1.1378066 PG 11 WC Physics, Fluids & Plasmas SC Physics GA 446RG UT WOS:000169525800031 ER PT J AU Lanier, NE Craig, D Anderson, JK Biewer, TM Chapman, BE Den Hartog, DJ Forest, CB Prager, SC Brower, DL Jiang, Y AF Lanier, NE Craig, D Anderson, JK Biewer, TM Chapman, BE Den Hartog, DJ Forest, CB Prager, SC Brower, DL Jiang, Y TI An investigation of density fluctuations and electron transport in the Madison Symmetric Torus reversed-field pinch SO PHYSICS OF PLASMAS LA English DT Article ID POLOIDAL CURRENT DRIVE; EDGE; INTERFEROMETER; CONFINEMENT; PLASMAS AB The origin of large scale density fluctuations and their role in electron transport has been investigated in the Madison Symmetric Torus reversed-field pinch [R. N. Dexter , Fusion Tech. 19, 131 (1991)]. At medium frequencies (10-30 kHz), (n) over tilde is associated with core-resonant magnetic fluctuations having poloidal mode number m=1 and toroidal mode numbers n=6-10. These chord-averaged density fluctuations are shown to be coherent with large scale radial flow fluctuations, permitting fluctuation-induced particle flux of the form <(n) over tilde(v) over tilde (r)> to be studied. In the edge, although amplitudes are large, (n) over tilde and (v) over tilde (r) are out of phase, consistent with advection of the mean density gradient by perturbed magnetic field lines and no electron transport. During improved confinement discharges, produced by inductive current drive, both fluctuation amplitudes and the total radial electron flux are greatly reduced over the entire plasma cross section. (C) 2001 American Institute of Physics. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Wisconsin, Dept Phys, Madison, WI 53706 USA. Univ Calif Los Angeles, Dept Elect Engn, Los Angeles, CA 90095 USA. RP Lanier, NE (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 30 TC 26 Z9 26 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD JUL PY 2001 VL 8 IS 7 BP 3402 EP 3410 DI 10.1063/1.1378328 PG 9 WC Physics, Fluids & Plasmas SC Physics GA 446RG UT WOS:000169525800032 ER PT J AU Thornhill, JW Apruzese, JP Davis, J Clark, RW Velikovich, AL Giuliani, JL Chong, YK Whitney, KG Deeney, C Coverdale, CA Cochran, FL AF Thornhill, JW Apruzese, JP Davis, J Clark, RW Velikovich, AL Giuliani, JL Chong, YK Whitney, KG Deeney, C Coverdale, CA Cochran, FL TI An efficient tabulated collisional radiative equilibrium radiation transport model suitable for multidimensional hydrodynamics calculations SO PHYSICS OF PLASMAS LA English DT Article ID PHOTON-ESCAPE PROBABILITIES; Z-PINCH; ARRAY IMPLOSIONS; EMISSION; EQUATION AB A computationally efficient method for transporting radiation in multidimensional plasmas has been developed and evaluated. The basis of this method is a uniform plasma approximation that allows one to utilize existing escape probability techniques that are successfully used in one-dimensional (1D) calculations to approximately solve the multidimensional radiation transport problem. This method is superior to diffusion methods because (1) the probability of escape technique insures that the plasma goes to the correct optically thin and thick limits, (2) the effects of line absorption due to photoexcitations are modeled, and (3) this method uses source functions that are based on a self-consistent nonlocal thermodynamic equilibrium calculation, not an ad hoc assumption that the source functions are Planckian. This method is highly efficient because equation of state information from 1D calculations is tabulated as a function of plasma internal energy, ion density, and the line probability of escape from a uniform plasma, and then used in multidimensional calculations. Given the internal energy and ion density, and by calculating the line probability of escape from a zone of the multidimensional plasma, the equation of state, including emissivities and absorption coefficients, of the zone is determined from the table. Total radiative power, K-shell radiative power, total radiative yield, K-shell radiative yield, and plasma density and temperature profiles obtained from 1D Z-pinch calculations employing this method are in good agreement with the same powers, yields, and profiles calculated using a full radiation transport model. This method has been implemented in the 2D plasma radiating imploding source model code [F. L. Cochran , Phys. Plasmas 2, 2765 (1995)] to determine the influence of radiation transport in argon Z-pinch experiments performed on the Z machine [R. B. Spielman , Phys. Plasmas 5, 2105 (1998)] at Sandia National Laboratories. (C) 2001 American Institute of Physics. C1 USN, Radiat Hydrodynam Branch, Div Plasma Phys, Res Lab, Washington, DC 20375 USA. Berkeley Scholars, Springfield, VA 22150 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Thornhill, JW (reprint author), USN, Radiat Hydrodynam Branch, Div Plasma Phys, Res Lab, Washington, DC 20375 USA. RI Velikovich, Alexander/B-1113-2009 NR 19 TC 33 Z9 33 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 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD JUL PY 2001 VL 8 IS 7 BP 3480 EP 3489 DI 10.1063/1.1373415 PG 10 WC Physics, Fluids & Plasmas SC Physics GA 446RG UT WOS:000169525800042 ER PT J AU Morrison, KA Davidson, RC Paul, SF Belli, EA Chao, EH AF Morrison, KA Davidson, RC Paul, SF Belli, EA Chao, EH TI Expansion rate measurements at moderate pressure of non-neutral electron plasmas in the Electron Diffusion Gauge (EDG) experiment SO PHYSICS OF PLASMAS LA English DT Article ID MALMBERG-PENNING TRAP; BACKGROUND GAS-PRESSURE; TEST PARTICLE-TRANSPORT; NONNEUTRAL ION PLASMAS; VORTEX CRYSTALS; DYNAMICS; COLLISIONS; CONTAINMENT; CONFINEMENT; RELAXATION AB Measurements of the expansion rate of pure-electron plasmas have been performed on the Electron Diffusion Gauge (EDG) device at background helium gas pressures in the 5x10(-8) Torr to 2x10(-5) Torr range, where plasma expansion due to electron-neutral collisions dominates over plasma expansion due to trap asymmetries. It is found that the expansion rate, defined as the time rate of change of the particles' mean-square radius, scales approximately linearly with pressure and inversely as the square of the magnetic field strength in this regime, in agreement with classical predictions. (C) 2001 American Institute of Physics. C1 Princeton Univ, Plasma Phys Lab, Princeton, NJ 08543 USA. RP Morrison, KA (reprint author), Princeton Univ, Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 37 TC 5 Z9 5 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD JUL PY 2001 VL 8 IS 7 BP 3506 EP 3509 DI 10.1063/1.1374583 PG 4 WC Physics, Fluids & Plasmas SC Physics GA 446RG UT WOS:000169525800046 ER PT J AU Drell, SD AF Drell, SD TI Physics and national security: Of missiles, mines, and morality - Reply SO PHYSICS TODAY LA English DT Letter C1 Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Drell, SD (reprint author), Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0031-9228 J9 PHYS TODAY JI Phys. Today PD JUL PY 2001 VL 54 IS 7 BP 12 EP 12 PG 1 WC Physics, Multidisciplinary SC Physics GA 447XP UT WOS:000169598000006 ER PT J AU Ben-Zvi, I AF Ben-Zvi, I TI Accelerator Test Facility hosts user-oriented research SO PHYSICS TODAY LA English DT Letter C1 Brookhaven Natl Lab, Upton, NY 11973 USA. RP Ben-Zvi, I (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0031-9228 J9 PHYS TODAY JI Phys. Today PD JUL PY 2001 VL 54 IS 7 BP 14 EP 14 DI 10.1063/1.1397383 PG 1 WC Physics, Multidisciplinary SC Physics GA 447XP UT WOS:000169598000009 ER PT J AU Moses, E AF Moses, E TI NIF's value questioned, affirmed - Reply SO PHYSICS TODAY LA English DT Letter C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Moses, E (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0031-9228 J9 PHYS TODAY JI Phys. Today PD JUL PY 2001 VL 54 IS 7 BP 14 EP 14 PG 1 WC Physics, Multidisciplinary SC Physics GA 447XP UT WOS:000169598000008 ER PT J AU Crease, RP AF Crease, RP TI Labs as crucibles of 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 JUL PY 2001 VL 14 IS 7 BP 16 EP 16 PG 1 WC Physics, Multidisciplinary SC Physics GA 459ZR UT WOS:000170281800017 ER PT J AU Gould, H AF Gould, H TI Molecular storage ring makes its debut SO PHYSICS WORLD LA English DT Article C1 Lawrence Berkeley Natl Lab, Berkeley, CA USA. RP Gould, H (reprint author), Lawrence Berkeley Natl Lab, Berkeley, CA USA. NR 0 TC 0 Z9 0 U1 0 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0953-8585 J9 PHYS WORLD JI Phys. World PD JUL PY 2001 VL 14 IS 7 BP 22 EP 23 PG 2 WC Physics, Multidisciplinary SC Physics GA 459ZR UT WOS:000170281800026 ER PT J AU Singleton, J AF Singleton, J TI Organic metal challenges superconductor paradigm SO PHYSICS WORLD LA English DT Article C1 Univ Oxford, Clarendon Lab, Oxford OX1 3PU, England. Los Alamos Natl Lab, Natl High Magnet Field Lab, Los Alamos, NM 87545 USA. RP Singleton, J (reprint author), Univ Oxford, Clarendon Lab, Parks Rd, Oxford OX1 3PU, England. NR 0 TC 4 Z9 4 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 JUL PY 2001 VL 14 IS 7 BP 23 EP 24 PG 2 WC Physics, Multidisciplinary SC Physics GA 459ZR UT WOS:000170281800027 ER PT J AU Li, L Howe, GA AF Li, L Howe, GA TI Alternative splicing of prosystemin pre-mRNA produces two isoforms that are active as signals in the wound response pathway SO PLANT MOLECULAR BIOLOGY LA English DT Article DE alternative splicing; prosystemin; signal transduction; systemin; tomato; wound response ID TRANSGENIC TOMATO PLANTS; MESSENGER-RNA; OLIGOSACCHARIDE ELICITORS; DEFENSIVE GENES; DNA-BINDING; SYSTEMIN; POLYPEPTIDE; EXPRESSION; DOMAIN; LEAVES AB Systemin and its precursor protein, prosystemin, play an essential role in the systemic wound response pathway of tomato plants. We report here the isolation from tomato of a novel prosystemin cDNA (prosysB) that differs from the reported cDNA sequence (prosysA) by the addition of a CAG trinucleotide. Inspection of the prosystemin genomic sequence, which was mapped to the central region of chromosome 5, indicated that prosysA and prosysB transcripts are generated by an alternative splicing event that utilizes different 3' splice sites within intron 3. Quantitative RT-PCR analysis showed that prosysB transcripts accumulated to approximately twice the level of prosysA in all tissues that express the prosystemin gene. The relative abundance of the two mRNAs was unaffected by wounding or methyl jasmonate treatment, conditions that increase the level of total prosys mRNA. These findings indicate that alternative splicing of prosys pre-mRNA is a constitutive process. The amino acid sequence of prosysB is predicted to differ from that of prosysA by replacement of Arg-57 with Thr-Gly in the non-systemin portion of the protein. Over-expression of the prosysB cDNA in transgenic tomato plants conferred constitutive expression of defense genes that are regulated by wounding and systemin. We conclude that prosysB is the major prosystemin-encoding transcript in tomato, and that this isoform is active as a signal in the wound response pathway. C1 Michigan State Univ, DOE Plant Res Lab, E Lansing, MI 48824 USA. Michigan State Univ, Dept Biochem & Mol Biol, E Lansing, MI 48824 USA. RP Howe, GA (reprint author), Michigan State Univ, DOE Plant Res Lab, E Lansing, MI 48824 USA. FU NIGMS NIH HHS [R01GM57795] NR 40 TC 33 Z9 35 U1 1 U2 7 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0167-4412 J9 PLANT MOL BIOL JI Plant Mol.Biol. PD JUL PY 2001 VL 46 IS 4 BP 409 EP 419 DI 10.1023/A:1010645330275 PG 11 WC Biochemistry & Molecular Biology; Plant Sciences SC Biochemistry & Molecular Biology; Plant Sciences GA 443GK UT WOS:000169332900004 PM 11485198 ER PT J AU Challis, CD Baranov, YF Conway, GD Gormezano, C Gowers, CW Hawkes, NC Hender, TC Joffrin, E Mailloux, J Mazon, D Podda, S Prentice, R Rimini, FG Sharapov, SE Sips, ACC Stratton, BC Testa, D Zastrow, KD AF Challis, CD Baranov, YF Conway, GD Gormezano, C Gowers, CW Hawkes, NC Hender, TC Joffrin, E Mailloux, J Mazon, D Podda, S Prentice, R Rimini, FG Sharapov, SE Sips, ACC Stratton, BC Testa, D Zastrow, KD TI Effect of q-profile modification by LHCD on internal transport barriers in JET SO PLASMA PHYSICS AND CONTROLLED FUSION LA English DT Article; Proceedings Paper CT 27th European-Physical-Society Conference on Controlled Fusion and Plasma Physics CY JUN 12-16, 2000 CL BUDAPEST, HUNGARY SP European Phys Soc ID REVERSED-MAGNETIC SHEAR; HYBRID CURRENT DRIVE; HIGH-BETA(P) DISCHARGES; OPTIMIZED SHEAR; PLASMA; PERFORMANCE; CONFINEMENT; TOKAMAKS; SUPPRESSION; REGIMES AB Optimized shear (OS) experiments in JET can generate an internal transport barrier (ITB) during a high power heating phase early in the plasma discharge. A strong link is generally observed between the formation of the barrier and the location of an integer q magnetic surface within a low magnetic shear (s = r/q(dq/dr)) region of the plasma. However, if the q-profile for such experiments is modified by applying lower hybrid heating and current drive (LHCD) before the main heating pulse, to provide a region of reduced or negative magnetic shear in the plasma core, ITBs can be formed the location of which does not exhibit any apparent association with a particular internal magnetic surface. Initial results suggest that q-profile modification using an LHCD prelude can also be used to reduce the heating power level required for ITB generation. C1 UKAEA Euratom Fus Assoc, Culham Sci Ctr, Abingdon OX14 3DB, Oxon, England. EURATOM, IPP, Max Planck Inst Plasmaphys, D-85740 Garching, Germany. ENEA Fus, Ctr Ric Energia, EURATOM Assoc, I-00044 Frascati, Rome, Italy. CEN Cadarache, EURATOM Assoc, CEA Fus, F-13108 St Paul Les Durance, France. Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. MIT, Plasma Sci & Fus Ctr, Cambridge, MA 02139 USA. RP UKAEA Euratom Fus Assoc, Culham Sci Ctr, Abingdon OX14 3DB, Oxon, England. NR 33 TC 92 Z9 92 U1 2 U2 10 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 JUL PY 2001 VL 43 IS 7 BP 861 EP 879 DI 10.1088/0741-3335/43/7/303 PG 19 WC Physics, Fluids & Plasmas SC Physics GA 457FB UT WOS:000170125500003 ER PT J AU Konoshima, S Leonard, AW Ishijima, T Shimizu, K Kamata, I Meyer, WH Sakurai, S Kubo, H Hosogane, N Tamai, H AF Konoshima, S Leonard, AW Ishijima, T Shimizu, K Kamata, I Meyer, WH Sakurai, S Kubo, H Hosogane, N Tamai, H TI Tomographic reconstruction of bolometry for JT-60U diverted tokamak characterization SO PLASMA PHYSICS AND CONTROLLED FUSION LA English DT Article ID X-RAY TOMOGRAPHY; DIII-D; PLASMAS; RADIATION; JET; IMPURITIES; DISCHARGES; TRANSPORT; ASDEX AB First results of the two-dimensionally reconstructed distribution of divertor radiation in JT-60U are presented. Hardware improvements of in-vessel divertor bolometer cameras to withstand severe electrical and thermal loads and the development of tomography software have made detailed and visual studies of divertor radiation possible. Line-integrated bolometer signals are successfully mapped onto the JT-60U geometry, indicating characteristic profiles for radiative divertor operation. A unique measurement of the radiating layer width at the target plate independently confirms the results of tomographic analysis. Radiation which is almost uniformly distributed along the separatrix flux line from the inboard to the outboard divertor is identified in the moderate density H-mode. Temporal evolution of radiative collapse due to heavy argon radiation is explored. Difficulties in the reconstruction associated with the local hot spot and neutrals are also discussed. C1 Japan Atom Energy Res Inst, Naka, Ibaraki 3110193, Japan. Gen Atom Co, San Diego, CA USA. Univ Tsukuba, Plasma Res Ctr, Tsukuba, Ibaraki 305, Japan. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA USA. RP Konoshima, S (reprint author), Japan Atom Energy Res Inst, Naka, Ibaraki 3110193, Japan. EM konoshis@fusion.naka.jaeri.go.jp RI Ishijima, Tatsuo/C-3337-2015; OI Ishijima, Tatsuo/0000-0002-5237-3699 NR 49 TC 19 Z9 21 U1 0 U2 5 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 JUL PY 2001 VL 43 IS 7 BP 959 EP 983 DI 10.1088/0741-3335/43/7/309 PG 25 WC Physics, Fluids & Plasmas SC Physics GA 457FB UT WOS:000170125500009 ER PT J AU Kuruganti, A Chen, KS Kalu, EE AF Kuruganti, A Chen, KS Kalu, EE TI Evaluation of a printable catalyst for use in flex-circuit & PCB applications SO PLATING AND SURFACE FINISHING LA English DT Article ID DEPOSITION AB In this study, a catalyzation technique for electroless deposition was investigated as an alternate method in flex-circuit and printed circuit board fabrications. The method involved a chemical reduction of metal ion in solution on a surface that is made active by printed catalyst. Two commercial electroless copper deposition baths containing formaldehyde as a reductant and EDTA as a complexant were used to study the influence of several deposition parameters. The morphology of the deposited copper, plating rate and adhesion issues are discussed, The nature of copper deposited was studied by scanning microscopy (SEM), atomic force microscopy (AFM) and X-ray diffraction (XRD) techniques. Results obtained from the evaluation of the two electroless copper baths showed that bath temperature and rate of bath agitation are critical issues that affect the adhesion of deposited copper with the new catalyzation technique. C1 Sandia Natl Labs, Tech Staff, Livermore, CA 94550 USA. FAMU FSU, Coll Engn, Dept Chem Engn, Tallahassee, FL 32307 USA. RP Kalu, EE (reprint author), FAMU FSU, Coll Engn, Dept Chem Engn, Tallahassee, FL 32307 USA. NR 14 TC 3 Z9 3 U1 0 U2 4 PU AMER ELECTROPLATERS SOC INC PI ORLANDO PA 12644 RESEARCH PKWY, ORLANDO, FL 32826-3298 USA SN 0360-3164 J9 PLAT SURF FINISH JI Plat. Surf. Finish. PD JUL PY 2001 VL 88 IS 7 BP 60 EP 66 PG 7 WC Metallurgy & Metallurgical Engineering; Materials Science, Coatings & Films SC Metallurgy & Metallurgical Engineering; Materials Science GA 453UJ UT WOS:000169934600014 ER PT J AU Green, MA Emery, K King, DL Igari, S Warta, W AF Green, MA Emery, K King, DL Igari, S Warta, W TI Solar cell efficiency tables (version 18) SO PROGRESS IN PHOTOVOLTAICS LA English DT Article AB Consolidated tables showing an extensive listing of the highest independently confirmed efficiencies for solar cells and modules are presented. Guidelines for inclusion of results into these tables are outlined and new entries, since January 2001, are reviewed. Copyright (C) 2001 John Wiley & Sons, Ltd. C1 Univ New S Wales, Ctr Photovolta Engn, Sydney, NSW 2052, Australia. Natl Renewable Energy Lab, Golden, CO 80401 USA. Sandia Natl Labs, Div 6224, Albuquerque, NM 87185 USA. Japan Qual Assurance Org, Minato Ku, Tokyo 1070052, Japan. Fraunhofer Inst Solar Energy Syst, D-79100 Freiburg, Germany. RP Green, MA (reprint author), Univ New S Wales, Ctr Photovolta Engn, Sydney, NSW 2052, Australia. NR 38 TC 31 Z9 31 U1 2 U2 21 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 1062-7995 J9 PROG PHOTOVOLTAICS JI Prog. Photovoltaics PD JUL-AUG PY 2001 VL 9 IS 4 BP 287 EP 293 DI 10.1002/pip.389 PG 7 WC Energy & Fuels; Materials Science, Multidisciplinary; Physics, Applied SC Energy & Fuels; Materials Science; Physics GA 461XF UT WOS:000170388600005 ER PT J AU Grigoriev, IV Zhang, C Kim, SH AF Grigoriev, IV Zhang, C Kim, SH TI Sequence-based detection of distantly related proteins with the same fold SO PROTEIN ENGINEERING LA English DT Article ID PREDICTED SECONDARY STRUCTURE; HIDDEN MARKOV-MODELS; REMOTE HOMOLOGS; PSI-BLAST; RECOGNITION; ALIGNMENT; DATABASE; MATRICES; IDENTIFICATION; INFORMATION C1 Univ Calif Berkeley, Melvin Calvin Lab 220, Dept Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, EO Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Kim, SH (reprint author), Univ Calif Berkeley, Melvin Calvin Lab 220, Dept Chem, Berkeley, CA 94720 USA. NR 38 TC 4 Z9 4 U1 0 U2 0 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0269-2139 J9 PROTEIN ENG JI Protein Eng. PD JUL PY 2001 VL 14 IS 7 BP 455 EP 458 DI 10.1093/protein/14.7.455 PG 4 WC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology SC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology GA 473CK UT WOS:000171021900001 PM 11522917 ER PT J AU Iakoucheva, LM Kimzey, AL Masselon, CD Smith, RD Dunker, AK Ackerman, EJ AF Iakoucheva, LM Kimzey, AL Masselon, CD Smith, RD Dunker, AK Ackerman, EJ TI Aberrant mobility phenomena of the DNA repair protein XPA SO PROTEIN SCIENCE LA English DT Article DE XPA; ESI-FTICR mass spectrometry; DNA repair; gel electrophoresis; SDS-PAGE; intrinsic disorder; partial proteolysis ID NUCLEOTIDE EXCISION-REPAIR; SIZE-EXCLUSION CHROMATOGRAPHY; A COMPLEMENTING PROTEIN; BINDING DOMAIN; MASS-SPECTROMETRY; LIMITED PROTEOLYSIS; POLYACRYLAMIDE GELS; XENOPUS-LAEVIS; DAMAGED DNA; RECOGNITION AB The DNA repair protein XPA recognizes a wide variety of bulky lesions and interacts with several other proteins during nucleotide excision repair. We recently identified regions of intrinsic order and disorder in full length Xenopus XPA (xXPA) protein using an experimental approach that combined time-resolved trypsin proteolysis and electrospray ionization interface coupled to a Fourier transform ion cyclotron resonance (ESI-FTICR) mass spectrometry (MS). MS data were consistent with the interpretation that xXPA contains no post-translational modifications. Here we characterize the discrepancy between the calculated molecular weight (31 kDa) for xXPA and its apparent molecular weight on SDS-PAGE (multiple bands from similar to 40-45 kDa) and gel filtration chromatography (similar to 92 kDa), as well as the consequences of DNA binding on its anomalous mobility. Iodoacetamide treatment of xXPA prior to SDS-PAGE yielded a single 42-kDa band, showing that covalent modification of Cys did not correct aberrant mobility. Determination of sulfhydryl content in xXPA with Ellman's reagent revealed that all nine Cys in active protein are reduced. Unexpectedly, structural constraints induced by intramolecular glutaraldehyde crosslinks in xXPA produced a similar to 32-kDa monomer in closer agreement with its calculated molecular weight. To investigate whether binding to DNA alters xXPA's anomalous migration, we used gel filtration chromatography. For the first time, we purified stable complexes of xXPA and DNA +/- cisplatin +/- mismatches. xXPA showed at least 10-fold higher affinity for cisplatin DNA +/- mismatches compared to undamaged DNA F mismatches. In all cases, DNA binding did not correct xXPA's anomalous migration. To test predictions that a Glu-rich region (EEEEAEE) and/or disordered N- and C-terminal domains were responsible for xXPA's aberrant mobility, the molecular weights of partial proteolytic fragments from similar to5 to 25 kDa separated by reverse-phase HPLC and precisely determined by ESI-FTICR MS were correlated with their migration on SDS-PAGE, Every partial tryptic fragment analyzed within this size range exhibited 10%-50% larger molecular weights than expected, Thus, both the disordered domains and the Glu-rich region in xXPA are primarily responsible for the aberrant mobility phenomena. C1 Pacific NW Natl Lab, Mol Biosci Dept, Richland, WA 99352 USA. PNNL, Environm Mol Sci Lab, Richland, WA 99352 USA. Washington State Univ, Sch Mol Biosci, Pullman, WA 99164 USA. RP Ackerman, EJ (reprint author), Pacific NW Natl Lab, Mol Biosci Dept, POB 999, Richland, WA 99352 USA. RI Masselon, Christophe/A-2340-2010; Smith, Richard/J-3664-2012; OI Smith, Richard/0000-0002-2381-2349; Iakoucheva, Lilia/0000-0002-4542-5219 NR 46 TC 80 Z9 82 U1 0 U2 6 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 JUL PY 2001 VL 10 IS 7 BP 1353 EP 1362 DI 10.1110/ps.40101 PG 10 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 445KT UT WOS:000169457200008 PM 11420437 ER PT J AU Patton, HJ Mitchell, BJ AF Patton, HJ Mitchell, BJ TI Monitoring the comprehensive nuclear-test-ban treaty - Introduction SO PURE AND APPLIED GEOPHYSICS LA English DT Editorial Material C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. St Louis Univ, Dept Earth & Atmospher Sci, St Louis, MO 63103 USA. RP Patton, HJ (reprint author), Los Alamos Natl Lab, POB 1663,MS D408, Los Alamos, NM 87545 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU BIRKHAUSER VERLAG AG PI BASEL PA VIADUKSTRASSE 40-44, PO BOX 133, CH-4010 BASEL, SWITZERLAND SN 0033-4553 J9 PURE APPL GEOPHYS JI Pure Appl. Geophys. PD JUL PY 2001 VL 158 IS 7 BP 1119 EP 1120 PG 2 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 463LB UT WOS:000170476700002 ER PT J AU McNamara, DE Walter, WR AF McNamara, DE Walter, WR TI Mapping crustal heterogeneity using Lg propagation efficiency throughout the Middle East, Mediterranean, Southern Europe and Northern Africa SO PURE AND APPLIED GEOPHYSICS LA English DT Article DE Lg regional phase seismology; attenuation; CTBT; nuclear explosion ID SEISMIC-WAVE PROPAGATION; LATERAL VARIATIONS; REGIONAL DISTANCES; TIBETAN PLATEAU; UPPER-MANTLE; SHEAR-WAVES; ATTENUATION; SEA; DISCRIMINATION; LITHOSPHERE AB In this paper we describe a technique for mapping the lateral variation of Lg characteristics such as Lg blockage, efficient Lg propagation, and regions of very high attenuation in the Middle East, North Africa, Europe and the Mediterranean regions. Lg is used in a variety of seismological applications from magnitude estimation to identification of nuclear explosions for monitoring compliance with the Comprehensive Nuclear-Test-Ban Treaty (CTBT). These applications can give significantly biased results if the Lg phase is reduced or blocked by discontinuous structure or thin crust. Mapping these structures using quantitative techniques for determining Lg amplitude attenuation can break down when the phase is below background noise. In such cases Lg blockage and inefficient propagation zones are often mapped out by hand. With our approach, we attempt to visually simplify this information by imaging crustal structure anomalies that significantly diminish the amplitude of Lg. The visualization of such anomalies is achieved by defining a grid of cells that covers the entire region of interest. We trace Lg rays for each event/station pair, which is simply the great circle path, and attribute to each cell a value equal to the maximum value of the Lg/P-coda amplitude ratio for all paths traversing that particular cell. The resulting map, from this empirical approach, is easily interpreted in terms of crustal structure and can successfully image small blockage features often missed by analysis of raypaths alone. This map can then be used to screen out events with blocked Lg prior to performing Q tomography. and to avoid using Lg-based methods of event identification for the CTBT in regions where they cannot work. For this study we applied our technique to one of the most tectonically complex regions on the earth. Nearly 9000 earthquake/station raypaths, traversing the vast region comprised of the Middle East. Mediterranean, Southern Europe and Northern Africa, have been analyzed. We measured the amplitude of Lg relative to the P-coda and mapped the lateral variation of Lg propagation efficiency. With the relatively dense coverage provided by the numerous crossing paths we are able to map out the pattern of crustal heterogeneity that gives rise to the observed character of Lg propagation. We observe that the propagation characteristics of Lg within the region of interest are very complicated but are readily correlated with the different tectonic environments within the region. For example, clear strong Lg arrivals are observed for paths crossing the stable continental interiors of Northern Africa and the Arabian Shield. In contrast, weakened to absent Lg is observed for paths crossing much of the Middle East, and Lg is absent for paths traversing the Mediterranean. Regions that block Lg transmission within the Middle East are very localized and include the Caspian Sea, the Iranian Plateau and the Red Sea. Resolution is variable throughout the region and strongly depends on the distribution of seismicity and recording stations. Lg propagation is best resolved within the Middle East where regions of crustal heterogeneity on the order of 100 km are imaged (e.g., South Caspian Sea and Red Sea). Crustal heterogeneity is resolvable but is poorest in seismicaily quiescent Northern Africa. C1 US Geol Survey, Denver, CO 80225 USA. Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP McNamara, DE (reprint author), US Geol Survey, Box 25046,MS 966, Denver, CO 80225 USA. RI Walter, William/C-2351-2013 OI Walter, William/0000-0002-0331-0616 NR 32 TC 18 Z9 18 U1 0 U2 1 PU BIRKHAUSER VERLAG AG PI BASEL PA VIADUKSTRASSE 40-44, PO BOX 133, CH-4010 BASEL, SWITZERLAND SN 0033-4553 J9 PURE APPL GEOPHYS JI Pure Appl. Geophys. PD JUL PY 2001 VL 158 IS 7 BP 1165 EP 1188 DI 10.1007/PL00001219 PG 24 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 463LB UT WOS:000170476700004 ER PT J AU Phillips, WS Hartse, HE Taylor, SR Velasco, AA Randall, GE AF Phillips, WS Hartse, HE Taylor, SR Velasco, AA Randall, GE TI Application of regional phase amplitude tomography to seismic verification SO PURE AND APPLIED GEOPHYSICS LA English DT Article DE discrimination; tomography; path correction; L-g blockage ID WESTERN UNITED-STATES; LG CODA-Q; LATERAL VARIATIONS; WAVE-PROPAGATION; NTS EXPLOSIONS; CENTRAL-ASIA; CHINA; DISCRIMINATION; EARTHQUAKES; ATTENUATION AB We have applied tomographic techniques to amplitude data to quantify regional phase path effects for use in source discrimination studies. Tomography complements interpolation (kriging) methods by extending our ability to apply path corrections into regions devoid of calibration events, as well as raising levels of confidence in the corrections because of their more physical basis. Our tomography technique solves for resolvable combinations of attenuation, source-generation, site and spreading terms, First difference regularization is used to remove singularities and reduce noise effects. In initial tests the technique was applied to a data set of 1488, 1.0 Hz, P-g/L-g amplitude ratios from 13 stations for paths inside a 30 degrees by 40 degrees box covering western China and surrounding regions. Tomography reduced variance 60%, relative to the power-law distance correction traditionally applied to amplitude ratios. Relative P-g/L-g attenuation varied with geologic region, with low values in Tibet, intermediate values in basins and high values for platforms and older crust. Spatial patterns were consistent with previous path effect studies in Asia, especially local earthquake coda-Q. Relative spreading was consistent with expected values for P-g and L-g. Relative site terms were similar to one another, yet some tradeoff with attenuation was evident. Tomography residuals followed systematic trends with distance, which may result from the evolution from direct to coda phases, focusing, model tradeoff or data windowing effects. Examination of the residuals using a kriging interpolator showed coherent geographical variations, indicating unmodeled path effects. The residual patterns often follow geological boundaries, which could result from attenuating zones or minor blockages that are too thin to be resolved, or that have anisotropic effect on regional phases. These results will guide efforts to reparameterize tomography models to more effectively represent regional wave attenuation and blockage. The interpolated residuals also can be combined with predictions of the tomographic model to account for path effects in discrimination studies on a station by station basis. C1 Los Alamos Natl Lab, Seism Res Ctr, Los Alamos, NM 87545 USA. RP Phillips, WS (reprint author), Los Alamos Natl Lab, Seism Res Ctr, POB 1663, Los Alamos, NM 87545 USA. NR 37 TC 14 Z9 14 U1 0 U2 3 PU BIRKHAUSER VERLAG AG PI BASEL PA VIADUKSTRASSE 40-44, PO BOX 133, CH-4010 BASEL, SWITZERLAND SN 0033-4553 J9 PURE APPL GEOPHYS JI Pure Appl. Geophys. PD JUL PY 2001 VL 158 IS 7 BP 1189 EP 1206 DI 10.1007/PL00001220 PG 18 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 463LB UT WOS:000170476700005 ER PT J AU Clough, RL Hill, DJT AF Clough, RL Hill, DJT TI Radiation chemistry of polymers - 14-19 December 2000, Honolulu, HI, USA - Preface SO RADIATION PHYSICS AND CHEMISTRY LA English DT Editorial Material C1 Sandia Natl Labs, Mat Aging & Reliabil Dept, Albuquerque, NM 87185 USA. Univ Queensland, Dept Chem, Ctr Magnet Resonance, Polymer Mat & Radiat Grp, Brisbane, Qld 4072, Australia. RP Clough, RL (reprint author), Sandia Natl Labs, Mat Aging & Reliabil Dept, POB 5800, Albuquerque, NM 87185 USA. NR 0 TC 0 Z9 0 U1 0 U2 2 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0969-806X J9 RADIAT PHYS CHEM JI Radiat. Phys. Chem. PD JUL PY 2001 VL 62 IS 1 BP 1 EP 1 DI 10.1016/S0969-806X(01)00413-3 PG 1 WC Chemistry, Physical; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical SC Chemistry; Nuclear Science & Technology; Physics GA 474BG UT WOS:000171084000001 ER PT J AU Alam, TM AF Alam, TM TI O-17 NMR investigation of radiolytic hydrolysis in polysiloxane composites SO RADIATION PHYSICS AND CHEMISTRY LA English DT Article; Proceedings Paper CT Pacifichem 2000 Meeting CY DEC 14-19, 2000 CL HONOLULU, HAWAII DE polysiloxane; O-17 NMR; polymer degradation; hydrolysis; PDMS; PDPS; gamma-irradiation ID THERMAL-DEGRADATION; CLAY-MINERALS; SI-29 NMR; C-13 NMR; SPECTROSCOPY; POLYETHYLENE; RADIATION; MECHANISM; SILICONE; H-1 AB The gamma -irradiated hydrolysis of polysiloxane composites was investigated as a function of gamma -irradiation dose using O-17 nuclear magnetic resonance (NMR) spectroscopy. It is demonstrated that by using O-17 labeled water during the high humidity exposure of the siloxane copolymer, details about the radiolytic hydrolysis degradation mechanism can be obtained directly from analysis of the O-17 NMR spectra. The formation of O-17 labeled silanols and Si-O-Si linkages occurs during the radiolytic hydrolysis, with the silanol species being the dominant non-volatile degradation product observed. For the polysiloxane composite investigated the distribution of hydrolysis species shows little variation at high total irradiation doses. In addition, the silica filler does have an effect on the distribution of the hydrolysis species within the copolymer at lower gamma -irradiation doses. The ability of O-17 NMR to isolate the hydrolysis species from other degradation processes within the polysiloxane composites demonstrates the applicability of this technique to address hydrolytic aging in other materials. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Sandia Natl Labs, Dept Organ Mat, Albuquerque, NM 87185 USA. RP Alam, TM (reprint author), Sandia Natl Labs, Dept Organ Mat, MS 0888, Albuquerque, NM 87185 USA. NR 35 TC 12 Z9 12 U1 2 U2 9 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0969-806X J9 RADIAT PHYS CHEM JI Radiat. Phys. Chem. PD JUL PY 2001 VL 62 IS 1 BP 145 EP 152 DI 10.1016/S0969-806X(01)00432-7 PG 8 WC Chemistry, Physical; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical SC Chemistry; Nuclear Science & Technology; Physics GA 474BG UT WOS:000171084000020 ER PT J AU Celina, M Gillen, KT Malone, GM Clough, RL Nelson, WH AF Celina, M Gillen, KT Malone, GM Clough, RL Nelson, WH TI Polymer materials and component evaluation in acidic-radiation environments SO RADIATION PHYSICS AND CHEMISTRY LA English DT Article; Proceedings Paper CT Pacifichem 2000 Meeting CY DEC 14-19, 2000 CL HONOLULU, HAWAII DE polymer degradation; performance evaluation; radiation; thermal; acidic; aging; component assessment; hostile environments ID OXIDATIVE-DEGRADATION; AGING DATA; EXTRAPOLATION; TEMPERATURE; ARRHENIUS; MODEL AB Polymeric materials used for cable/wire insulation, electrical connectors, O-rings, seals, and in critical components such as motors, level switches and resistive thermo-devices. were evaluated under accelerated degradation conditions in combined radiation-oxidative elevated-temperature acidic-vapor (nitric/oxalic) environments relevant to conditions in isotope processing facilities. Experiments included the assessment of individual materials such as PEEK, polyimides, polyolefin based cable insulation, EPDM rubbers, various epoxy systems, commercial caulking materials as well as some functional testing of components. We discuss how to conduct laboratory experiments to simulate such complex hostile environments, describe some degradation effects encountered, and evaluate the impact on appropriate material and component selection. Published by Elsevier Science Ltd. C1 Queensland Univ Technol, Brisbane, Qld 4001, Australia. Sandia Natl Labs, Dept 1811, Albuquerque, NM 87185 USA. US DOE, Aiken, SC 29808 USA. RP Celina, M (reprint author), Queensland Univ Technol, Brisbane, Qld 4001, Australia. NR 32 TC 8 Z9 9 U1 0 U2 2 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0969-806X J9 RADIAT PHYS CHEM JI Radiat. Phys. Chem. PD JUL PY 2001 VL 62 IS 1 BP 153 EP 161 DI 10.1016/S0969-806X(01)00433-9 PG 9 WC Chemistry, Physical; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical SC Chemistry; Nuclear Science & Technology; Physics GA 474BG UT WOS:000171084000021 ER PT J AU Pierpoint, S Silverman, J Al-Sheikhly, M AF Pierpoint, S Silverman, J Al-Sheikhly, M TI Effects of ionizing radiation on the aging of polyester based polyurethane binder SO RADIATION PHYSICS AND CHEMISTRY LA English DT Article; Proceedings Paper CT Pacifichem 2000 Meeting CY DEC 14-19, 2000 CL HONOLULU, HAWAII DE estane; polyester polyurethane; irradiation; cross-linking; free radical AB The effects of radiation on the aging of estane were investigated using both electron beam and gamma irradiation at various dose rates in the presence and absence of oxygen. It was found using GPC technique that, in the presence and absence of oxygen, estane primarily undergoes rapid cross-linking, by means of a carbon-centered secondary alkyl radical. It was also concluded that estane partially undergoes scission reactions as a result of breakage in the backbone of the main chain at C-O, N-C, and C-C bonds. The C-centered free radical which is produced via C-C scission (primary alkyl radical) is rapidly converted to a long-lived allylic species, which, in the presence of oxygen, undergoes a fast reaction to produce a peroxyl radical; this radical decays with a 1.7 h half-life by pseudo first-order kinetics to negligible levels in 13 h. FTIR measurements show an increase in carbonyl, amine and carboxylic groups as a result of reaction of H atoms with R-C-O-., (NH)-N-.-R, and R-COO.. The FTIR results also demonstrated the production of the unsaturation resulting from hydrogen atom transfer during intrachain conversion of the primary alkyl radical to the allyl species, prompt trans-vinylene production in tetramathylene units, and hydrogen atom abstraction by alkyl radicals from alkyl radicals on neighboring chains. (C) 2001 Published by Elsevier Science Ltd. C1 Univ Maryland, Dept Mat & Nucl Engn, College Pk, MD 20742 USA. US DOE, Germantown, MD 20874 USA. RP Al-Sheikhly, M (reprint author), Univ Maryland, Dept Mat & Nucl Engn, College Pk, MD 20742 USA. NR 10 TC 29 Z9 29 U1 0 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0969-806X J9 RADIAT PHYS CHEM JI Radiat. Phys. Chem. PD JUL PY 2001 VL 62 IS 1 BP 163 EP 169 DI 10.1016/S0969-806X(01)00434-0 PG 7 WC Chemistry, Physical; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical SC Chemistry; Nuclear Science & Technology; Physics GA 474BG UT WOS:000171084000022 ER PT J AU Anderson, CW Dunn, JJ Freimuth, PI Galloway, AM Allalunis-Turner, MJ AF Anderson, CW Dunn, JJ Freimuth, PI Galloway, AM Allalunis-Turner, MJ TI Frameshift mutation in PRKDC, the gene for DNA-PKcs, in the DNA repair-defective, human, glioma-derived cell line M059J SO RADIATION RESEARCH LA English DT Article ID DEPENDENT PROTEIN-KINASE; SINGLE-NUCLEOTIDE POLYMORPHISMS; CATALYTIC SUBUNIT; MESSENGER-RNA; V(D)J RECOMBINATION; NONSENSE CODONS; KU-AUTOANTIGEN; P53 INDUCTION; SCID MOUSE; DAMAGE AB The glioma-derived cell line M059J is hypersensitive to ionizing radiation, lacks DNA-PK activity, and fails to express protein for the catalytic subunit, DNA-PKcs, while a sister cell line, M059K, derived from the same tumor, has normal DNA-PK activity. Both cell lines are near pentaploid and have multiple copies of chromosome 8, the chromosome on which the DNA-PKcs gene, PRKDC, is located. Sequence analysis of PCR-amplified exons revealed the loss in M059J cells of a single "A" nucleotide in exon 32, corresponding to the first nucleotide of codon 1351 (ACC, Thr) of PRKDC. Loss of the "A" nucleotide would terminate the DNA-PKcs reading frame early in exon 33, DNA from M059K cells had only the wild-type sequence. An analysis of sequences surrounding PRKDC ex-on 32 from 87 unrelated individuals revealed no polymorphic nucleotides except for a triplet repeat near the 3' end of this exon; no individual had a frameshift mutation in exon 32. No other sequence differences in PRKDC between M059J and M059K cells were observed in similar to 15,000 bp of genomic sequence including the sequences of exons 5 through 38 and surrounding intron sequence, suggesting a possible reduction to homozygosity at this locus prior to acquisition of the mutation leading to the M059J cell line. (C) 2001 by Radiation Research Society. C1 Brookhaven Natl Lab, Dept Biol, Upton, NY 11973 USA. Univ Alberta, Dept Oncol, Edmonton, AB T6G 1Z2, Canada. Cross Canc Inst, Edmonton, AB T6G 1Z2, Canada. RP Anderson, CW (reprint author), Brookhaven Natl Lab, Dept Biol, Upton, NY 11973 USA. FU NIGMS NIH HHS [GM52825] NR 45 TC 49 Z9 54 U1 1 U2 1 PU RADIATION RESEARCH SOC PI OAK BROOK PA 820 JORIE BOULEVARD, OAK BROOK, IL 60523 USA SN 0033-7587 J9 RADIAT RES JI Radiat. Res. PD JUL PY 2001 VL 156 IS 1 BP 2 EP 9 DI 10.1667/0033-7587(2001)156[0002:FMIPTG]2.0.CO;2 PG 8 WC Biology; Biophysics; Radiology, Nuclear Medicine & Medical Imaging SC Life Sciences & Biomedicine - Other Topics; Biophysics; Radiology, Nuclear Medicine & Medical Imaging GA 452MG UT WOS:000169861700002 PM 11418067 ER PT J AU Kraemer, SM Vannais, DB Kronenberg, A Ueno, A Waldren, CA AF Kraemer, SM Vannais, DB Kronenberg, A Ueno, A Waldren, CA TI Gamma-ray mutagenesis studies in a new human-hamster hybrid, A(L)CD59(+/-), which has two human chromosomes 11 but is hemizygous for the CD59 gene SO RADIATION RESEARCH LA English DT Article ID RADIATION-INDUCED MUTATION; THYMIDINE KINASE GENE; CELL-SURFACE ANTIGEN; MAMMALIAN-CELLS; ALPHA-PARTICLES; HOMOLOGOUS RECOMBINATION; MOLECULAR ANALYSIS; ANCHOR SYNTHESIS; MUTANT QUANTITY; CULTURED HUMAN AB We have developed a human-CHO hybrid cell Line, named A(L)CD59(+/-), which has two copies of human chromosome 11 but is hemizygous for the CD59 gene and the CD59 cell surface antigen that it encodes. Our previous studies used the A(L) and A(L)C hybrids that respectively contain one or two sets of CHO chromosomes plus a single copy of human chromosome 11. The CD59 gene at 11p13.5 and the CD59 antigen encoded by it are the principal markers used in our mutagenesis studies. The hybrid A(L)CD59(+/-) contains two copies of human chromosome II, only one of which carries the CD59 gene. The incidence of CD59- mutants (formerly called S1-) induced by Cs-137 gamma rays is about fivefold greater in A(L)CD59(+/-) cells than in A, cells, Evidence is presented that this increase in mutant yield is due to the increased induction of certain classes of large chromosomal mutations that are lethal to A, cells but are tolerated in the A(L)CD59(+/-) hybrid. In addition, significantly more of the CD59 mutants induced by Cs-137 gamma rays in A(L)CD59(+/-) cells display chromosomal instability than in A, cells. On the other hand, the yield of gamma -ray-induced CD59 mutants in A(L)CD59(+/-) cells is half that of the A(L)C hybrid, which also tolerates very large mutations but has only one copy of human chromosome 11, We interpret the difference in mutability as evidence that repair processes involving the homologous chromosomes 11 play a role in determining mutant yields, The A(L)CD59(+/-) hybrid provides a useful new tool for quantifying mutagenesis and shedding light on mechanisms of genetic instability and mutagenesis. (C) 2001 by Radiation Research Society. C1 Colorado State Univ, Dept Biochem & Mol Biol, Ft Collins, CO 80523 USA. Colorado State Univ, Dept Radiol Hlth Sci, Ft Collins, CO 80523 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, Berkeley, CA 94720 USA. RP Kraemer, SM (reprint author), Colorado State Univ, Dept Biochem & Mol Biol, Ft Collins, CO 80523 USA. FU NCI NIH HHS [5T32 CA09236, CA36447] NR 67 TC 13 Z9 13 U1 0 U2 1 PU RADIATION RESEARCH SOC PI OAK BROOK PA 820 JORIE BOULEVARD, OAK BROOK, IL 60523 USA SN 0033-7587 J9 RADIAT RES JI Radiat. Res. PD JUL PY 2001 VL 156 IS 1 BP 10 EP 19 DI 10.1667/0033-7587(2001)156[0010:GRMSIA]2.0.CO;2 PG 10 WC Biology; Biophysics; Radiology, Nuclear Medicine & Medical Imaging SC Life Sciences & Biomedicine - Other Topics; Biophysics; Radiology, Nuclear Medicine & Medical Imaging GA 452MG UT WOS:000169861700003 PM 11418068 ER PT J AU Jacobson, AR Shao, XM AF Jacobson, AR Shao, XM TI Using geomagnetic birefringence to locate sources of impulsive, terrestrial VHF signals detected by satellites on orbit SO RADIO SCIENCE LA English DT Article ID FORTE AB The Earth's ionosphere is magnetized by the geomagnetic field and imposes birefringent modulation on VHF radio signals propagating through the ionosphere. Satellites viewing VHF emissions from terrestrial sources receive ordinary and extraordinary modes successively from each broadband pulse emitted by the source. The birefringent intermode frequency separation can be used to determine the value of f(ce) cos beta, where f(ce) is the electron gyrofrequency and beta is the angle between the wave vector k and the geomagnetic field B at the point where the VHF ray path intersects the ionosphere. Successive receptions of multiple signals (from the same source) cause variation in f(ce) cos beta, and from the resulting variation in the signal intermode frequency separation the source location on Earth can be inferred. We test the method with signals emitted by the Los Alamos Portable Pulser and received by the FORTE satellite. C1 Univ Calif Los Alamos Natl Lab, Space & Atmospher Sci Grp, Los Alamos, NM 87545 USA. RP Jacobson, AR (reprint author), Univ Calif Los Alamos Natl Lab, Space & Atmospher Sci Grp, Mail Stop D466, Los Alamos, NM 87545 USA. NR 4 TC 16 Z9 16 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0048-6604 J9 RADIO SCI JI Radio Sci. PD JUL-AUG PY 2001 VL 36 IS 4 BP 671 EP 680 DI 10.1029/2000RS002555 PG 10 WC Astronomy & Astrophysics; Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Remote Sensing; Telecommunications SC Astronomy & Astrophysics; Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Remote Sensing; Telecommunications GA 456UX UT WOS:000170101600015 ER PT J AU Badea, EA Everett, ME Shen, LC Weiss, CJ AF Badea, EA Everett, ME Shen, LC Weiss, CJ TI Effect of background fields on three-dimensional finite element analysis of induction logging SO RADIO SCIENCE LA English DT Article AB Three-dimensional controlled-source electromagnetic induction algorithms are generally formulated in terms of secondary fields or potentials. The selection of the primary solution is somewhat arbitrary but can greatly influence the efficiency of finite element codes. A simple induction logging problem demonstrates this statement. Responses are computed using a three-dimensional finite element method for two different selections of the primary potential, one that includes the borehole effect and one that does not. The accuracy of the numerical solution, for a given mesh size, increases dramatically when the borehole effect is included in the primary solution. This is because the sharp gradients in the electromagnetic field near the transmitter due to the presence of the borehole are coded as an analytic source term and do not have to be captured by the numerical approximation. Whenever possible, finite element analysts should select a convenient primary solution that closely matches the anticipated total solution in the immediate vicinity of the transmitter. C1 Univ Houston, Dept Elect & Comp Engn, Houston, TX 77204 USA. Texas A&M Univ, Dept Geol & Geophys, College Stn, TX 77843 USA. Sandia Natl Labs, Geophys Technol Dept, Albuquerque, NM 87185 USA. RP Badea, EA (reprint author), Univ Houston, Dept Elect & Comp Engn, Houston, TX 77204 USA. NR 12 TC 3 Z9 3 U1 8 U2 10 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0048-6604 J9 RADIO SCI JI Radio Sci. PD JUL-AUG PY 2001 VL 36 IS 4 BP 721 EP 729 DI 10.1029/2000RS002576 PG 9 WC Astronomy & Astrophysics; Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Remote Sensing; Telecommunications SC Astronomy & Astrophysics; Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Remote Sensing; Telecommunications GA 456UX UT WOS:000170101600019 ER PT J AU Witt, CE Mitchell, RL Thomas, HP Symko-Davies, M AF Witt, CE Mitchell, RL Thomas, HP Symko-Davies, M TI Terrestrial photovoltaic technologies update SO RENEWABLE ENERGY LA English DT Article DE photovoltaics; PV technologies; terrestrial PV applications; PV manufacturing costs AB A description of terrestrial photovoltaics (PV), what it is and what it accomplishes, and a very brief historical perspective of its development are presented. Todays leading technologies are identified and discussed. Current areas for improvement and suggestions for future R&D focus are presented. Information is provided on the latest developments in terms of efficiencies, cost, industry output and prospects. The most suited applications are also addressed. (C) 2001 Published by Elsevier Science Ltd. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Witt, CE (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. NR 5 TC 1 Z9 1 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0960-1481 J9 RENEW ENERG JI Renew. Energy PD JUL-AUG PY 2001 VL 23 IS 3-4 SI SI BP 349 EP 353 PG 5 WC GREEN & SUSTAINABLE SCIENCE & TECHNOLOGY; Energy & Fuels SC Science & Technology - Other Topics; Energy & Fuels GA 415VQ UT WOS:000167744600001 ER PT J AU Ekdahl, C AF Ekdahl, C TI Noninvasive measurement of electron-beam size with diamagnetic loops SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article AB Diamagnetic loops can be used as a noninvasive method for measurements of beam size in electron beam accelerators that use solenoidal magnetic transport. A comprehensive theory for interpreting data from a diamagnetic loop is developed. It is shown that the change in flux through a diamagnetic loop can be simply related to the rms beam radius to high accuracy, regardless of the details of the current profile, when the ratio of beam current to Alfven current I-b/I-A is small. The difficulty in making this measurement lies in the fact that the diamagnetic-loop signal is also small to the same order. (C) 2001 American Institute of Physics. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Ekdahl, C (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 8 TC 1 Z9 1 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JUL PY 2001 VL 72 IS 7 BP 2909 EP 2914 DI 10.1063/1.1379605 PG 6 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 449BB UT WOS:000169663500008 ER PT J AU Darrow, DS Werner, A Weller, A AF Darrow, DS Werner, A Weller, A TI Energetic ion loss diagnostic for the Wendelstein 7-AS stellarator SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article ID FUSION PRODUCTS; OPERATION; DETECTORS; TFTR AB A diagnostic to measure the loss of energetic ions from the Wendelstein 7-AS (W7-AS) stellarator has been built. It is capable of measuring losses of both neutral beam ions and energetic ions arising from ion cyclotron resonant heating. The probe can measure losses of both clockwise and counterclockwise-going energetic ions simultaneously, and accepts a wide range of pitch angles in both directions. Initial measurements by the diagnostic are reported. (C) 2001 American Institute of Physics. C1 Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. Max Planck Inst Plasmaphys, D-85748 Garching, Germany. RP Darrow, DS (reprint author), Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 15 TC 14 Z9 14 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JUL PY 2001 VL 72 IS 7 BP 2936 EP 2942 DI 10.1063/1.1379602 PG 7 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 449BB UT WOS:000169663500013 ER PT J AU Richter, A Guico, R Wang, J AF Richter, A Guico, R Wang, J TI Calibrating an ellipsometer using x-ray reflectivity SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article ID ALKYLSILOXANES; MONOLAYERS; SILICON AB X-ray reflectivity has been used to find the optical refractive index of polymer thin film in order to calibrate a Stokes ellipsometer for film thickness measurements during the deposition procedure. A thin, spun-cast film of poly(tert-butyl acrylate) (PtBA) was made with a film thickness of similar to 500 Angstrom. An x-ray reflectivity measurement was taken and the data were fit to determine the thickness of the PtBA film and the underlying silicon-oxide layer. This measurement was then used to calculate the optical refractive index for PtBA at the ellipsometer wavelength. Using this value for the refractive index subsequently allowed us to determine the film thickness for a series of PtBA films made by using a number of polymer solution concentrations resulting in film thickness ranging from 100 to 1300 Angstrom. These film thicknesses were found to be generally the same as those found using x-ray reflectivity. The success of this procedure suggests a useful method for calibrating an ellipsometer for fast in-lab measurements, especially on ultrathin films when simultaneous determination of the film thickness and the refractive index is less reliable. (C) 2001 American Institute of Physics. C1 Argonne Natl Lab, User Program Div, Argonne, IL 60439 USA. Northwestern Univ, Dept Mat Sci & Engn, Evanston, IL 60208 USA. RP Wang, J (reprint author), Argonne Natl Lab, User Program Div, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 7 TC 11 Z9 12 U1 0 U2 6 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JUL PY 2001 VL 72 IS 7 BP 3004 EP 3007 DI 10.1063/1.1379603 PG 4 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 449BB UT WOS:000169663500024 ER PT J AU Partouche-Sebban, D Holtkamp, DB Bartsch, RR Lee, H Schmitt, GG AF Partouche-Sebban, D Holtkamp, DB Bartsch, RR Lee, H Schmitt, GG TI Application of a high speed, low temperature infrared pyrometer in pulsed power experiments SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article AB A new, multichannel infrared (IR) pyrometer has been constructed that is capable of measuring low temperature changes (< 100 degreesC) at high speed (multi-MHz). The pyrometer has four IR channels spanning 1-11 mum and uses 1 mm optical fibers to relay the light from the center of a pulsed power experiment to the detectors. Broad IR passbands are used to increase sensitivity while preserving high accuracy in the temperature measurement (< 15% for the absolute temperature (K) up to 1300 K). An application of the pyrometer in material property measurements of high strain at high strain rate is described. (C) 2001 American Institute of Physics. C1 CEA, Direct Rech Ile France, F-91680 Bruyeres Le Chatel, France. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Partouche-Sebban, D (reprint author), CEA, Direct Rech Ile France, BP12, F-91680 Bruyeres Le Chatel, France. NR 3 TC 9 Z9 9 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JUL PY 2001 VL 72 IS 7 BP 3008 EP 3012 DI 10.1063/1.1376653 PG 5 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 449BB UT WOS:000169663500025 ER PT J AU Althouse, WE Hand, SD Jones, LK Lazzarini, A Weiss, R AF Althouse, WE Hand, SD Jones, LK Lazzarini, A Weiss, R TI Precision alignment of the LIGO 4 km arms using the dual-frequency differential global positioning system SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article AB The alignment of the Laser Interferometer Gravitational-Wave Observatory (LIGO) using the global positioning system (GPS) is described. The LIGO project is designed to detect gravitational waves from astrophysical sources by laser interferometry. There are two sites separated by 3002 km that will be operated in coincidence. At each site, laser beams propagate in two orthogonal 4 km long evacuated beam lines 1.2 m in diameter. The subject of this article is the alignment of the 16 km of beam tubes using dual-frequency differential GPS. A maximum deviation from straightness in inertial space of 5 mm root mean square and an orthogonality between arm pairs of better than 5 mu rad is reported. Analysis of the as-built alignment data allows determination of the geodetic coordinates for the vertices and the arm orientations at both sites. From this information, the baseline distance between the vertices of the Hanford, Washington and Livingston, Louisiana sites was determined to be 3001.8 km. (C) 2001 American Institute of Physics. C1 CALTECH, LIGO Lab, Pasadena, CA 91125 USA. Stanford Linear Accelerator Ctr, Menlo Park, CA 94025 USA. Jacobs Engn, Livermore, CA 94550 USA. CB&I, Plainfield, IL 60606 USA. MIT, LIGO Lab, Cambridge, MA 02139 USA. RP Althouse, WE (reprint author), CALTECH, LIGO Lab, Pasadena, CA 91125 USA. NR 11 TC 7 Z9 7 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD JUL PY 2001 VL 72 IS 7 BP 3086 EP 3094 DI 10.1063/1.1376138 PG 9 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 449BB UT WOS:000169663500035 ER PT J AU Salamon, MB Jaime, M AF Salamon, MB Jaime, M TI The physics of manganites: Structure and transport SO REVIEWS OF MODERN PHYSICS LA English DT Review ID METAL-INSULATOR-TRANSITION; IONIC FERROMAGNET (LAPB)MNO3; COLOSSAL-MAGNETORESISTANCE MANGANITES; PEROVSKITE OXIDES LA1-XCAXMNO3; LA0.67CA0.33MNO3 THIN-FILMS; LOCAL LATTICE-DISTORTIONS; TEMPERATURE SPECIFIC-HEAT; MIXED-VALENCE MANGANITES; EU-CHALCOGENIDE ALLOYS; JAHN-TELLER PHONONS AB The fundamental physical properties of doped LaMnO3, generically termed "manganites," and much of the underlying physics, were known more than 40 years ago. This article first reviews progress made at that time, the concept of double exchange in particular, and points out the missing elements that have led to a massive resurgence of interest in these and related materials. More recent research is then described, treating first the ground states that emerge as divalent atoms are substituted for trivalent La. A wide range of ground states appear, including ferromagnetic metals, orbital- and charge-ordered antiferromagnets, and more complex stripe and spin-glass states. Because of the interest in so-called colossal magnetoresistance that occurs in the ferromagnetic/metallic composition range, a section is devoted to reviewing the atypical properties of that phase. Next the high-temperature phase is examined, in particular, evidence for the formation of self-trapped small polarons and the importance of Jahn-Teller coupling ia this process. The transitions between the high-temperature polaronic phase and the ferromagnetic and charge-ordered states are treated in a fourth section. In each section, the authors stress the competition among charge, spin, and lattice coupling and review the current state of theoretical understanding. They conclude with some comments on the impact that research on these materials has on our understanding of doped oxides and other strongly correlated electronic materials. C1 Univ Illinois, Dept Phys, Urbana, IL 61801 USA. Univ Illinois, Mat Res Lab, Urbana, IL 61801 USA. Los Alamos Natl Lab, MST, NHMFL, Los Alamos, NM 87545 USA. RP Salamon, MB (reprint author), Univ Illinois, Dept Phys, 1110 W Green St, Urbana, IL 61801 USA. RI Jaime, Marcelo/F-3791-2015 OI Jaime, Marcelo/0000-0001-5360-5220 NR 231 TC 1518 Z9 1562 U1 51 U2 532 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0034-6861 J9 REV MOD PHYS JI Rev. Mod. Phys. PD JUL PY 2001 VL 73 IS 3 BP 583 EP 628 DI 10.1103/RevModPhys.73.583 PG 46 WC Physics, Multidisciplinary SC Physics GA 493YG UT WOS:000172250600002 ER PT J AU Jackson, JD Okun, LB AF Jackson, JD Okun, LB TI Historical roots of gauge invariance SO REVIEWS OF MODERN PHYSICS LA English DT Review ID FOCK,V.A.; BIRTH AB Gauge invariance is the basis of the modern theory of electroweak and strong interactions (the so-called standard model). A number of authors have discussed the ideas and history of quantum guage theories, beginning with the 1920s, but the roots of gauge invariance go back to the year 1820 when electromagnetism was discovered and the first electrodynamic theory was proposed. We describe the 19th century developments that led to the discovery that different forms of the vector potential (differing by the gradient of a scalar function) are physically equivalent, if accompanied by a change in the scalar potential: A -->A'=A+del chi, Phi --> Phi'=Phi-partial derivative chi /c partial derivativet. L. V. Lorenz proposed the condition partial derivative (mu)A(mu)=0 in the mid-1860s, but this constraint is generally misattributed to the better known H. A. Lorentz. In the work in 1926 on the relativistic wave equation for a charged spinless particle in an electromagnetic field by Schrodinger, Klein, and Fock, it was Fock who discovered the invariance of the equation under the above changes in A and Phi if the wave function was transformed according to psi --> psi=psi exp(ie chi /hc). In 1929, H. Weyl proclaimed this invariance as a general principle and called it Eichinvarianz in German and gauge invariance in English. The present era of non-Abelian gauge theories started in 1954 with the paper by Yang and Mills on isospin gauge invariance. C1 Univ Calif Berkeley, Berkeley, CA 94720 USA. Lawrence Berkeley Lab, Berkeley, CA 94720 USA. State Sci Ctr Russian Federat, Inst Theoret & Expt Phys, Moscow 117218, Russia. RP Jackson, JD (reprint author), Univ Calif Berkeley, Berkeley, CA 94720 USA. NR 115 TC 86 Z9 91 U1 1 U2 15 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0034-6861 J9 REV MOD PHYS JI Rev. Mod. Phys. PD JUL PY 2001 VL 73 IS 3 BP 663 EP 680 DI 10.1103/RevModPhys.73.663 PG 18 WC Physics, Multidisciplinary SC Physics GA 493YG UT WOS:000172250600004 ER PT J AU Gillen, KT Terrill, ER Winter, RM AF Gillen, KT Terrill, ER Winter, RM TI Modulus mapping of rubbers using micro- and nano-indentation techniques SO RUBBER CHEMISTRY AND TECHNOLOGY LA English DT Review ID DIFFUSION-LIMITED OXIDATION; ATOMIC-FORCE MICROSCOPY; NANOSCALE PROPERTY VARIATIONS; POLYMER COMPOSITE SYSTEMS; THERMALLY AGED ELASTOMERS; OXYGEN DIFFUSION; ELASTIC-MODULUS; TIME DEVELOPMENT; PROFILES; DEGRADATION AB Modulus measurements are among the most useful properties available for monitoring the cure and aging of rubbers. Historically, such measurements were done on macroscopic samples, but over the past 15 years, several penetration techniques have been and are being developed that allow quantitative estimates of modulus to be made with lateral resolutions of 100 mum or better. This review summarizes these developments and the types of unique information that can be generated on rubbery materials. A large part of the review focuses on the types of results available from a modulus profiling apparatus that has been used to study rubbers for the past 15 years. This instrument allows estimates to be made of the inverse tensile compliance (closely related to Young's tensile modulus) with a lateral resolution of around 50 to 100 mum. Several recently developed alternative methods for achieving similar spatial resolution are also described. Finally, a brief review is given of the recent attempts to measure quantitative modulus values for rubbers with even better resolution using instruments historically focused on metals and other hard materials such as nano-indenters, the atomic force microscope and the interfacial force microscope. C1 Sandia Natl Labs, Albuquerque, NM 87818 USA. Goodyear Tire & Rubber Co, Akron, OH 44305 USA. S Dakota Sch Mines & Technol, Dept Chem & Chem Engn, Rapid City, SD 57701 USA. RP Sandia Natl Labs, POB 5800, Albuquerque, NM 87818 USA. EM ktgille@sandia.gov NR 77 TC 22 Z9 24 U1 1 U2 12 PU AMER CHEMICAL SOC INC PI AKRON PA RUBBER DIV UNIV AKRON PO BOX 499, AKRON, OH 44309-0499 USA SN 0035-9475 EI 1943-4804 J9 RUBBER CHEM TECHNOL JI Rubber Chem. Technol. PD JUL-AUG PY 2001 VL 74 IS 3 BP 428 EP 450 DI 10.5254/1.3547646 PG 23 WC Polymer Science SC Polymer Science GA 568NY UT WOS:000176549600007 ER PT J AU Morton, LS Evans, CV Harbotle, G Estes, GO AF Morton, LS Evans, CV Harbotle, G Estes, GO TI Pedogenic fractionation and bioavailability of uranium and thorium in naturally radioactive spodosols SO SOIL SCIENCE SOCIETY OF AMERICA JOURNAL LA English DT Article ID CONCENTRATION RATIOS; HEAVY-METALS; SOILS; RADIONUCLIDES; EXTRACTION; BEHAVIOR; RADIUM AB Plant uptake of radionuclides into the human food chain is one of many vectors used for calculating exposure rates and performing risk assessment. This study provides a pedogenic assessment of soil-plant relationships in terms of their relationships to nuclide bioavailability. The objectives of this study were (i) to identify associations of U and Th with pedogenic fractions and with soil properties, and (ii) to evaluate U and Th bioavailability in terms of soil processes. We collected composite samples of leaves, stems, AE and Bs horizons from 10 plots containing a Spodosol with naturally high levels of U-238 and Th-232. Additional replicate subsamples of fine (< 63 mum) soil material were also extracted with citrate-bicarbonate-dithionite (CBD), ammonium oxalate (AO), sodium pyrophosphate (PP), and Mehlich reagent (M3). Concentrations of U-238 and Th-232 were determined for soils and plants by neutron activation analysis or by gamma spectroscopy. Results indicated that Th was translocated preferentially to plant leaves while U showed little preferential translocation. The CBD extractant removed the most U and Th from soils. The PP extraction ranked second for U, and AO ranked second for Th removal. The M3 extraction was equally inefficient in the removal of both U and Th. Neither Th, nor Th uptake, was closely associated with organic fractions. In contrast, U distribution and plant uptake of U were more closely correlated to organically bound oxide fractions. C1 Univ New Hampshire, Dept Nat Resources, Durham, NH 03824 USA. Univ New Hampshire, Dept Plant Biol, Durham, NH 03824 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. RP Evans, CV (reprint author), Univ Wisconsin Parkside, Dept Geol, Kenosha, WI 53141 USA. NR 33 TC 20 Z9 22 U1 0 U2 4 PU SOIL SCI SOC AMER PI MADISON PA 677 SOUTH SEGOE ROAD, MADISON, WI 53711 USA SN 0361-5995 J9 SOIL SCI SOC AM J JI Soil Sci. Soc. Am. J. PD JUL-AUG PY 2001 VL 65 IS 4 BP 1197 EP 1203 PG 7 WC Soil Science SC Agriculture GA 505NG UT WOS:000172918400021 ER PT J AU Zhai, HY Christen, HM Zhang, L Paranthaman, M Fleming, PH Lowndes, DH AF Zhai, HY Christen, HM Zhang, L Paranthaman, M Fleming, PH Lowndes, DH TI Degradation of superconducting properties in MgB2 films by exposure to water SO SUPERCONDUCTOR SCIENCE & TECHNOLOGY LA English DT Article ID PHASE AB The effect of water exposure on MgB2 is studied by submerging an 800 nm thick MgB2 film into de-ionized water at room temperature for 1 h, 4 h, 10 h, and 15 h, and by analysing the resulting material using scanning electron microscopy and resistance versus temperature measurements. It is clearly observed that the T-c(onset) of these films (obtained by an ex-situ reaction of an e-beam evaporated boron layer) remains unchanged throughout this process, indicating that at least a portion of the sample retains its original bulk-like properties. The data is consistent with an interpretation in which a portion of the exposed film-likely to be the region closest to the substrate-becomes superconducting only at similar to 25 K. It is possible that this low-T-c region already exists in the as-prepared film, and we observe that its T-c coincides with that of MgB2 films obtained by annealing precursor films prepared by pulsed laser deposition. Therefore the data presented here not only illustrates the degradation of MgB2 in water but also sheds light on the differences and similarities between films obtained via different routes. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37931 USA. RP Zhai, HY (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37931 USA. RI Christen, Hans/H-6551-2013; Paranthaman, Mariappan/N-3866-2015 OI Christen, Hans/0000-0001-8187-7469; Paranthaman, Mariappan/0000-0003-3009-8531 NR 21 TC 25 Z9 25 U1 1 U2 7 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0953-2048 J9 SUPERCOND SCI TECH JI Supercond. Sci. Technol. PD JUL PY 2001 VL 14 IS 7 BP 425 EP 428 DI 10.1088/0953-2048/14/7/301 PG 4 WC Physics, Applied; Physics, Condensed Matter SC Physics GA 457QJ UT WOS:000170148000005 ER PT J AU Okram, GS Terakura, C Uji, S Aoki, H Xu, M Hinks, DG AF Okram, GS Terakura, C Uji, S Aoki, H Xu, M Hinks, DG TI Dimensionality and lock-in transition in Tl2Ba2CuO6 single crystal SO SUPERCONDUCTOR SCIENCE & TECHNOLOGY LA English DT Article ID HIGH-TEMPERATURE SUPERCONDUCTORS; CA-CU-O; LAYERED SUPERCONDUCTORS; JOSEPHSON VORTICES; PHASE-TRANSITION; MAGNETIC-FIELD; MIXED STATE; CROSSOVER; DEPENDENCE AB The lock-in transition on good-quality over-doped Tl2Ba2CuO6 single crystal was investigated. The observed sharp drop, a dip and a peak together in the flux flow resistivity rho(theta) as the magnetic field angle theta with the c-axis approaches 90 degrees have been ascribed to vortex phase transitions of different types. A demonstration of the inadequacy of the two models of the angular dependence of the upper critical fields to explain this phenomenon is presented here. C1 Natl Phys Lab, Cryogen & Superconduct Grp, New Delhi 110012, India. Natl Res Inst Met, Tsukuba, Ibaraki 305, Japan. Tohoku Univ, Ctr Low Temp Sci, Sendai, Miyagi 98077, Japan. Univ Chicago, James Franck Inst, Chicago, IL 60637 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Okram, GS (reprint author), Natl Phys Lab, Cryogen & Superconduct Grp, Dr K S Krishnan Rd, New Delhi 110012, India. RI Terakura, Chieko/A-5959-2009 NR 20 TC 1 Z9 1 U1 1 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0953-2048 J9 SUPERCOND SCI TECH JI Supercond. Sci. Technol. PD JUL PY 2001 VL 14 IS 7 BP 452 EP 456 DI 10.1088/0953-2048/14/7/306 PG 5 WC Physics, Applied; Physics, Condensed Matter SC Physics GA 457QJ UT WOS:000170148000010 ER PT J AU Kameda, J Nishiyama, Y Bloomer, TE AF Kameda, J Nishiyama, Y Bloomer, TE TI Non-equilibrium intergranular segregation and embrittlement in neutron-irradiated ferritic alloys SO SURFACE AND INTERFACE ANALYSIS LA English DT Article DE non-equilibrum intergranular segregation; neutron irradiation; post irradiation annealing; P-interstitial complex; vacancy-enhanced diffusion; segregation capacity; intergranular embrittlement ID GRAIN-BOUNDARY SEGREGATION; BRITTLE-FRACTURE; KINETIC-MODEL; SMALL-PUNCH; PHOSPHORUS; CARBON AB This study describes intergranular segregation and embrittlement in several model ferritic alloys doped with Mn, P, S and/or Cu subjected to neutron irradiation, irradiation-equivalent thermal ageing (ETA) and post-irradiation annealing (PIA). Neutron irradiation produced a larger amount of intergranular phosphorus segregation than sulfur segregation. Irradiation-induced phosphorus segregation became more prominent with decreasing bulk phosphorus content. Intergranular carbon segregation remained small in all the as-irradiated alloys, which was enhanced by the ETA except for the high phosphorus-containing alloy. A PIA study has shown that the phosphorus segregation in phosphorus-doped alloys subjected to lower temperature PIA proceeds via mobile phosphorus-interstitial complexes, whereas the sulfur segregation, which occurs over a wide PIA temperature range, is controlled by vacancy-enhanced diffusion. The mechanisms of non-equilibrium intergranular segregation induced by neutron irradiation are discussed in light of coupled fluxes of point defects and impurities and changes in the segregation capacity of grain boundaries. Small punch tests demonstrated how the impurity segregation or desegregation and hardening or softening induced by the irradiation, ETA and PIA influence intergranular embrittlement in the various ferritic alloys. Copyright (C) 2001 John Wiley & Sons, Ltd. C1 Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. Off Naval Res, Int Field Off, Tokyo 106, Japan. Japan Atom Energy Res Inst, Tokai, Ibaraki 319, Japan. US Nucl Regulatory Commiss, Washington, DC 20555 USA. RP Kameda, J (reprint author), Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. NR 35 TC 9 Z9 9 U1 0 U2 3 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 0142-2421 J9 SURF INTERFACE ANAL JI Surf. Interface Anal. PD JUL PY 2001 VL 31 IS 7 BP 522 EP 531 DI 10.1002/sia.1080 PG 10 WC Chemistry, Physical SC Chemistry GA 456WV UT WOS:000170106500003 ER PT J AU Hughes, DA AF Hughes, DA TI Deformation microstructures and selected examples of their recrystallization SO SURFACE AND INTERFACE ANALYSIS LA English DT Article DE recrystallization; deformation; microstructure; dislocation; transmission electron microscopy ID COPPER SINGLE-CRYSTALS; COLD-ROLLED ALUMINUM; DISLOCATION BOUNDARIES; LOCAL CRYSTALLOGRAPHY; GRAIN-ORIENTATION; CELL STRUCTURES; LARGE STRAINS; TEXTURE; COMPRESSION; EVOLUTION AB The elements that are needed to describe a deformation structure -grains, grain boundaries, macroscale banding within crystals, cell blocks, geometrically necessary boundaries and incidental dislocation boundaries (cell boundaries)-are presented and described for fcc metals and alloys of medium to high stacking fault energy. Pertinent to this quantitative description are the local orientations, structural morphology, different boundary misorientations and spacings as a function of strain and deformation conditions. Three specific examples are given in which particular aspects of the deformation structure are shown to direct the recrystallization behavior. Copyright (C) 2001 John Wiley & Sons, Ltd; first published by Riso National Laboratory. C1 Sandia Natl Labs, Ctr Mat & Engn Sci, Livermore, CA 94551 USA. RP Hughes, DA (reprint author), Sandia Natl Labs, Ctr Mat & Engn Sci, Livermore, CA 94551 USA. NR 60 TC 6 Z9 6 U1 1 U2 9 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 0142-2421 J9 SURF INTERFACE ANAL JI Surf. Interface Anal. PD JUL PY 2001 VL 31 IS 7 BP 560 EP 570 DI 10.1002/sia.1083 PG 11 WC Chemistry, Physical SC Chemistry GA 456WV UT WOS:000170106500006 ER PT J AU Bruemmer, SM Thomas, LE AF Bruemmer, SM Thomas, LE TI High-resolution analytical electron microscopy characterization of corrosion and cracking at buried interfaces SO SURFACE AND INTERFACE ANALYSIS LA English DT Article DE corrosion; intergranular attack; electron microscopy ID STAINLESS-STEELS; MECHANISM; WATER AB Recent results are presented demonstrating the application of cross-sectional analytical transmission electron microscopy (ATEM) to corrosion and cracking in high-temperature water environments. Microstructural, chemical and crystallographic characterization of buried interfaces at near-atomic resolutions is shown to reveal evidence for unexpected local environments, corrosion reactions and material transformations. Information obtained by a wide variety of high-resolution imaging and analysis methods indicates the processes occurring during crack advance and provides insights into the mechanisms controlling environmental degradation. Examples of intergranular attack and cracking in type 316 austenitic stainless steel and Ni-based alloy 600 are presented to illustrate the potential for this approach. The presence of deeply attacked grain boundaries off the main cracks, revealed by TEM, is believed to indicate a major role of active corrosion in the stress corrosion cracking (SCC) process. Corroded boundaries were filled with oxides to the leading edges of attack. Analyses of the oxide films and impurities in the narrow intergranular penetrations and crack tips with widths of 10 nm or less indicate influences of the grain boundary characteristics and water chemistry. Boundary and precipitate corrosion structures can be used to identify the local electrochemistry promoting degradation in complex service environments. Solution impurities such as lead are found in high concentrations at nanometer-wide reaction zones in samples from secondary water environments, indicating water access at leading edges of the attack and the influence of these impurities on the corrosion processes. Results for specific samples are used to demonstrate the ability of cross-sectional ATEM to reveal new details of buried corrosion structures that cannot be detected by other methods. Copyright (C) 2001 John Wiley & Sons, Ltd. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Pacific NW Natl Lab, POB 999, Richland, WA 99352 USA. EM sm-bruemmer@pnl.gov NR 21 TC 37 Z9 37 U1 2 U2 18 PU WILEY-BLACKWELL PI HOBOKEN PA 111 RIVER ST, HOBOKEN 07030-5774, NJ USA SN 0142-2421 EI 1096-9918 J9 SURF INTERFACE ANAL JI Surf. Interface Anal. PD JUL PY 2001 VL 31 IS 7 BP 571 EP 581 DI 10.1002/sia.1084 PG 11 WC Chemistry, Physical SC Chemistry GA 456WV UT WOS:000170106500007 ER PT J AU Miller, MK AF Miller, MK TI Interface analysis with the three-dimensional atom probe SO SURFACE AND INTERFACE ANALYSIS LA English DT Article DE atom probe; grain boundary; segregation; microstructural; characterization ID FE-CR ALLOYS; FIELD-ION MICROSCOPY; SPINODAL DECOMPOSITION; COMPUTER-MODELS; LEVEL; SCALE AB The application of the technique of atom probe tomography to the atomic scale characterization of interfaces and surface films is described. The three-dimensional atom probe determines the coordinates and elemental identities of the atoms in a small volume of a sample with near-atomic precision. The types of analyses that may be performed on interfaces are demonstrated by examples taken from a variety of materials, including neutron-irradiated pressure-vessel steel welds, superalloys, surface films and model alloys. Published in 2001 by John Wiley & Sons, 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, Bldg 4500S MS 6136,POB 2008, Oak Ridge, TN 37831 USA. NR 29 TC 12 Z9 12 U1 0 U2 2 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 0142-2421 J9 SURF INTERFACE ANAL JI Surf. Interface Anal. PD JUL PY 2001 VL 31 IS 7 BP 593 EP 598 DI 10.1002/sia.1086 PG 8 WC Chemistry, Physical SC Chemistry GA 456WV UT WOS:000170106500009 ER PT J AU Anderson, IE Foley, JC AF Anderson, IE Foley, JC TI Determining the role of surfaces and interfaces in the powder metallurgy processing of aluminum alloy powders SO SURFACE AND INTERFACE ANALYSIS LA English DT Article DE aluminum atomization; sintering; NDE; explosivity; powder metallurgy AB The current options for solid-state consolidation processing of powder-based advanced aluminum alloys have been very limited and complicated, resulting in a segregation of the applications primarily to the aerospace segment. Throughout any consolidation sequence for aluminum powders, the oxide and/or hydroxide films on the typical powder surfaces can interfere with densification and interparticle bonding. In fact, the consolidation sequence for many low-strength aluminum alloy powder metallurgy parts involves transient liquid-phase sintering to massively disrupt the powder surfaces, producing improved bonding but introducing a coarsened resolidification microstructure. Although preventing aluminum oxide formation is nearly impossible during aluminum powder production, the gas atomization reaction synthesis (GARS) method - an advanced powder production technique - can modify the oxide coating and enable improved consolidation processing. This report compares the effects of the GARS process and other representative atomization processes on the surface structure and properties of aluminum powders and on their ability to sinter. The powders were characterized with transmission electron microscopy, scanning electron microscopy, Auger electron spectroscopy, quadrapole mass spectroscopy and with a new ultrasonic method for in situ sensing of the evolution of sintering. In general, a marked reduction in the surface film thickness and in the level of chemisorbed moisture and moisture-borne impurities was observed in the GARS powders. This change in powder surface characteristics also was effective in promoting sintering processes in the GARS powders, as monitored by our new technique. An initial direct comparison of explosivity for the different types of aluminum powder revealed that the GARS powder also had a reduced hazard level. All of these findings indicate that the GARS approach to aluminum powder production may enable mass-produced lightweight powder metallurgy parts from advanced aluminum alloys with simple consolidation processing techniques. Copyright (C) 2001 John Wiley & Sons, Ltd. C1 Ames Lab, Ames, IA 50011 USA. RP Anderson, IE (reprint author), Ames Lab, Ames, IA 50011 USA. NR 16 TC 27 Z9 28 U1 4 U2 16 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 0142-2421 J9 SURF INTERFACE ANAL JI Surf. Interface Anal. PD JUL PY 2001 VL 31 IS 7 BP 599 EP 608 DI 10.1002/sia.1087 PG 10 WC Chemistry, Physical SC Chemistry GA 456WV UT WOS:000170106500010 ER PT J AU Kim, SH Somorjai, GA AF Kim, SH Somorjai, GA TI Characterization of the Ziegler-Natta olefin polymerization system: surface science studies on model catalysts SO SURFACE AND INTERFACE ANALYSIS LA English DT Article DE catalysis; olefins; surface analysis ID CHLORIDE THIN-FILMS; ELECTRON-PARAMAGNETIC RESONANCE; SUM-FREQUENCY GENERATION; MAGNESIUM-CHLORIDE; TITANIUM CHLORIDE; ETHYLENE POLYMERIZATION; PROPYLENE POLYMERIZATION; HETEROGENEOUS CATALYSIS; PROPENE POLYMERIZATION; OXIDATION-STATES AB Modem surface science techniques have been applied to the heterogeneous Ziegler-Natta catalysis system, polymerizing alpha -olefins to produce polyolefins, and revealed the correlation between the catalyst surface structure and polymer properties. Two types of thin films - TiCl(x)/MgCl(2) and TiCl(y)/Au - were fabricated on an inert gold substrate, using chemical vapor deposition methods, to mimic the high-yield catalysts of MgCl(2)-supported TiCl(4) and TiCl(3)-based catalysts, respectively. Once activated with triethylaluminum (AlEt(3)) vapor, both catalysts were active for polymerization of ethylene and propylene in the absence of excess AlEt(3). The model catalyst films were as active as the high-surface-area industrial catalysts. Both catalysts were terminated with chlorine at the surface but had different surface structures. The TiCl(x)/MgCl(2) film had a distribution of two structures: the dominant sites had the (001) basal plane of these halide crystallites and the minority sites had a non-basal plane structure. The surface of the TiCl(y)/Au film assumed only the non-basal plane structure. These structural differences resulted in different tacticity of the polypropylene produced with these catalysts. The TiCl(x)/MgCl(2) catalyst produced both atactic and isotactic polypropylene, whereas the TiCl(y) catalyst without the MgCl(2) support produced exclusively isotactic polypropylene. The titanium oxidation states did not appear to be an important factor in determining the tacticity of the polypropylene. Copyright (C) 2001 John Wiley & Sons, Ltd. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Dept Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Div Mat Sci, Berkeley, CA 94720 USA. RP Somorjai, GA (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Dept Chem, D58 Hildebrand 1460, Berkeley, CA 94720 USA. EM Somorjai@socrates.berkeley.edu NR 98 TC 11 Z9 12 U1 1 U2 7 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 0142-2421 J9 SURF INTERFACE ANAL JI Surf. Interface Anal. PD JUL PY 2001 VL 31 IS 7 BP 701 EP 710 DI 10.1002/sia.1096 PG 10 WC Chemistry, Physical SC Chemistry GA 456WV UT WOS:000170106500019 ER PT J AU Fitzpatrick, A AF Fitzpatrick, A TI A history of modern computing. SO TECHNOLOGY AND CULTURE LA English DT Book Review C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Fitzpatrick, A (reprint author), Los Alamos Natl Lab, Los Alamos, NM 87545 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU JOHNS HOPKINS UNIV PRESS PI BALTIMORE PA JOURNALS PUBLISHING DIVISION, 2715 NORTH CHARLES ST, BALTIMORE, MD 21218-4319 USA SN 0040-165X J9 TECHNOL CULT JI Technol. Cult. PD JUL PY 2001 VL 42 IS 3 BP 617 EP 618 DI 10.1353/tech.2001.0108 PG 2 WC History & Philosophy Of Science SC History & Philosophy of Science GA 458JC UT WOS:000170190400043 ER PT J AU Kato-Weinstein, J Orner, GA Thrall, BD Bull, RJ AF Kato-Weinstein, J Orner, GA Thrall, BD Bull, RJ TI Differences in the detection of c-Jun/ubiquitin immunoreactive proteins by different c-Jun antibodies SO TOXICOLOGY METHODS LA English DT Article DE antibody; c-Jun; dichloroacetate; ubiquitin ID TRANSCRIPTION FACTORS; ACTIVATION DOMAIN; HA-RAS; NEOPLASTIC TRANSFORMATION; SIGNAL-TRANSDUCTION; GLYCOGEN-METABOLISM; DNA-BINDING; JB6 CELLS; PHOSPHORYLATION; KINASE AB We compared the immunoreactivity of two widely used c-Jun polyclonal antibodies, SC-45 and Ab-1, in normal mouse hepatocytes and in hepatic tumors by means of immunohistochemistry and Western blotting. The epitope of SC-45 contains Thr 91 and Thr 93, both of which are phosphorylated by c-Jun N-terminal kinase. The epitope of Ab-1 contains Ser 252 which is phosphorylated by glycogen synthase kinase-3 (GSK-3) and casein kinase-II (CKII) and results in the inactivation of c-Jun. In dichloroacetate (DCA)-induced tumors, the protein detected by SC-45 was diffusely spread throughout the cytosol, whereas the protein detected by Ab-1 focused around the nuclei. In the liver tissue adjacent to the DCA-induced tumor, SC-45 stained protein in the nuclei, whereas there was no staining in the nuclei with Ab-1. In DCA-treated mice, SC-45 also detected an increased cytosolic expression of protein in cells that surrounded the central vein. This was not detected by Ab-1. Western blot analysis demonstrated that the c-Jun immunoreactive protein that was highly expressed in DCA-induced tumors was 55 kD rather than 39 kD in molecular weight. Interestingly, the apparent concentrations of the proteins detected at 55 kD varied reciprocally in tumors and in surrounding normal tissue. SC-45 detected higher amounts of the 55 kD protein in nontumor tissue, whereas Ab-1 detected higher amounts of the 55 kD protein in tumor tissue. Furthermore, DCA treatment (2 g/L, 8 weeks) significantly reduced the 55 kD protein detected by Ab-1, but the amount reacting with SC-45 was unchanged. An immunoprecipitation experiment suggested that the 55 kD c-Jun immunoreactive protein also reacted with a ubiquitin antibody. Ab-1 was not able to detect c-Jun protein when it was incubated with CKII, suggesting that the Ab-1 detects a form of c-Jun that has been dephosphorylated in the DNA-binding domain. SC-45 has been shown to detect the dephosphorylated form of c-Jun at Thr 91 and Thr 94. The immunological data obtained using these antibodies indicate that they are interacting with different posttranscriptionally modified forms of c-Jun. C1 Washington State Univ, Coll Pharm, Pharmacol Toxicol Program, Pullman, WA 99164 USA. Pacific NW Natl Lab, Richland, WA 99352 USA. RP Bull, RJ (reprint author), Washington State Univ Tricities Campus,2710 Univ, Richland, WA 99352 USA. RI Orner, Gayle/F-6876-2013 OI Orner, Gayle/0000-0002-4812-5297 NR 35 TC 0 Z9 0 U1 0 U2 1 PU TAYLOR & FRANCIS LTD PI LONDON PA 11 NEW FETTER LANE, LONDON EC4P 4EE, ENGLAND SN 1051-7235 J9 TOXICOL METHOD JI Toxicol. Method. PD JUL-SEP PY 2001 VL 11 IS 3 BP 189 EP 207 PG 19 WC Toxicology SC Toxicology GA 487MM UT WOS:000171879000005 ER PT J AU Wall, MA Schwartz, AJ Nguyen, L AF Wall, MA Schwartz, AJ Nguyen, L TI A high-resolution serial sectioning specimen preparation technique for application to electron backscatter diffraction SO ULTRAMICROSCOPY LA English DT Article DE serial sectioning; electron backscatter diffraction; metrology ID ORIENTATION IMAGING MICROSCOPY; BOUNDARY-CHARACTER-DISTRIBUTION; MECHANICAL-BEHAVIOR; TANTALUM PLATE; CORROSION; COPPER AB A high-resolution serial sectioning specimen preparation technique is described for acquisition of electron backscatter diffraction (EBSD) data. The primary objective is to develop a method to reproducibly remove a controlled thickness of material from a polycrystalline Ta sample while producing quality surfaces for EBSD orientation imaging. This is integrated with the ability to accurately measure the amount of material removed with each iteration and experimentally register the ensuing EBSD scans. To facilitate enhanced accuracy of this method, a metrology device containing high-precision etching patterns is fabricated using standard lithographic techniques. This metrology device allows for the sub-micron measurement of the serial section slice thickness and approximately 1 mum registration accuracy of each EBSD scan. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Calif Lawrence Livermore Natl Lab, Chem & Mat Sci Directorate, Livermore, CA 94550 USA. RP Wall, MA (reprint author), Univ Calif Lawrence Livermore Natl Lab, Chem & Mat Sci Directorate, L-356,7000 East Ave,POB 808, Livermore, CA 94550 USA. NR 23 TC 19 Z9 25 U1 0 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-3991 J9 ULTRAMICROSCOPY JI Ultramicroscopy PD JUL PY 2001 VL 88 IS 2 BP 73 EP 83 DI 10.1016/S0304-3991(01)00071-7 PG 11 WC Microscopy SC Microscopy GA 442BP UT WOS:000169265600001 PM 11419876 ER PT J AU Schroeder, JA Voelkl, E Hofstaedter, F AF Schroeder, JA Voelkl, E Hofstaedter, F TI Ultrastructural telepathology-remote EM-diagnostic via Internet SO ULTRASTRUCTURAL PATHOLOGY LA English DT Article DE diagnostic; dynamic imaging; electron microscopy; Internet; remote; ultrastructural telepathology ID ELECTRON-MICROSCOPY; TUMOR-DIAGNOSIS; FROZEN-SECTIONS; SURGICAL PATHOLOGY; TELEMEDICINE; TELEMICROSCOPY; SERVICES; SYSTEM; TOOL AB New collaboratory opportunities in ultrastructural research and diagnostics are now available on the Internet through the combination of digital image acquisition, remote operation of modern digitally controlled and automated electron microscopes, and the development of software specifically tailored for collaboratory needs. Remote experts can examine samples directly, and unique instruments can be utilized from anywhere. In the case of diagnostic dilemmas, the second-opinion expert is no longer constrained by problems inherent in the interpretation of preselected images. The remote examiner can independently choose the area of interest on the sample as well as select the appropriate magnification for an accurate diagnosis. With these capabilities and together with teleconferencing tools and securely accessible databases on-line, telepathology can provide increased effectiveness and support for diagnostics, research, and teaching in many areas. The authors report their experience with remote electron microscope diagnoses of pathological samples using two different dynamic imaging systems and discuss the main technical issues encountered. It appears that only minor technical issues need to be resolved before ultrastructural telepathology can be promoted for routine use in areas with high-speed Internet access. C1 Univ Clin Regensburg, Dept Pathol, D-93042 Regensburg, Germany. Oak Ridge Natl Lab, Oak Ridge, TN USA. RP Schroeder, JA (reprint author), Univ Clin Regensburg, Dept Pathol, FJ Strauss Allee 11, D-93042 Regensburg, Germany. EM josef.schroeder@klinik.uni-regensburg.de NR 54 TC 10 Z9 10 U1 1 U2 1 PU INFORMA HEALTHCARE PI NEW YORK PA 52 VANDERBILT AVE, NEW YORK, NY 10017 USA SN 0191-3123 J9 ULTRASTRUCT PATHOL JI Ultrastruct. Pathol. PD JUL-AUG PY 2001 VL 25 IS 4 BP 301 EP 307 PG 7 WC Microscopy; Pathology SC Microscopy; Pathology GA 475GV UT WOS:000171155000005 PM 11577775 ER PT J AU Tseng, PH Bussod, GY AF Tseng, PH Bussod, GY TI Evaluation of the filter paper technique for in situ sampling of solute transport in unsaturated soils and tuffs SO WATER RESOURCES RESEARCH LA English DT Article ID VOLUME-AVERAGED CONCENTRATIONS; TIME-DOMAIN REFLECTOMETRY; BOUNDARY-CONDITIONS; WATER; EQUATION; TENSION AB The performance of a filter paper sampling system for monitoring solute transport in unsaturated soils and tuffs was evaluated using numerical simulations. The sampling system consisted of a collection borehole and a sampling assembly designed specifically for the easy removal and replacement of a filter paper pad used to collect solution samples at locations throughout the borehole. Simulations were conducted to approximate an experimental setup at Busted Butte, Nevada, for two hypothetical soil formations: a Calico Hills tuff and a loamy sand. The purpose of the simulations was to evaluate any significant effects the sampling system might have on the prevailing flow and transport processes. The simulation results revealed that the overall disturbance of the system is a superposition of three major components caused by the installation and operation of the sampling device. Two of these components delayed the observed solute breakthroughs and hence increased the mean and variance of solute travel times, whereas the third disturbed the system by increasing the mean solute velocity. The analytical solution of the one-dimensional convective-dispersive equation in the fluid coordinate frame was introduced to approximate the system response at different levels of disturbance for a better understanding of the system dynamics. The general difficulties in interpreting flow and transport properties using field-measured data are illustrated. To better interpret field data, it is important to understand the limitations a measuring device may impose on data analysis. C1 Univ Calif Los Alamos Natl Lab, Geoanal Grp, Los Alamos, NM 87545 USA. RP Tseng, PH (reprint author), Univ Calif Los Alamos Natl Lab, Geoanal Grp, EES-5,MS-C306, Los Alamos, NM 87545 USA. NR 35 TC 3 Z9 3 U1 1 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0043-1397 J9 WATER RESOUR RES JI Water Resour. Res. PD JUL PY 2001 VL 37 IS 7 BP 1913 EP 1928 DI 10.1029/2001WR900012 PG 16 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA 445ZV UT WOS:000169489200006 ER PT J AU Scheu, C Stein, W Klein, S Wagner, T Tomsia, AP Ruhle, M AF Scheu, C Stein, W Klein, S Wagner, T Tomsia, AP Ruhle, M TI Microstructure and modifications of Cu/Al2O3 interfaces SO ZEITSCHRIFT FUR METALLKUNDE LA English DT Article DE Cu/Al2O3 interfaces; microstructure; transmission electron microscopy ID ELECTRON-ENERGY-LOSS; METAL-CERAMIC INTERFACES; LOSS SPECTROSCOPY; MICROSCOPY; SURFACE; COPPER; CHEMISTRY; OXYGEN; STATES AB A combined approach of high-resolution transmission electron microscopy and electron energy-loss near-edge structure studies was employed to determine the atomic structure and bonding mechanisms at Cu/Al2O3 interfaces in dependence on the alpha -Al2O3 substrate orientation. The investigated specimens were prepared by molecular beam epitaxy using ultrahigh vacuum conditions, which led to atomically abrupt interfaces. The results show that intermetallic Cu-Al bonds occur at the investigated Cu/(11 (2) over bar0)Al2O3 interface, while ionic-covalent bonding contributions are observed at the Cu/(0001)Al2O3 interface. The interfacial microstructure of diffusion-bonded Cu/(0001)Al2O3 samples was changed by annealing treatments under various oxygen partial pressures. Annealing resulted in the formation of a CuAlO2 reaction phase at the interface between Cu and Al2O3. C1 Max Planck Inst Met Res, D-70174 Stuttgart, Germany. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Ruhle, M (reprint author), Max Planck Inst Met Res, Seestr 92, D-70174 Stuttgart, Germany. NR 32 TC 7 Z9 7 U1 1 U2 2 PU CARL HANSER VERLAG PI MUNICH PA KOLBERGERSTRASSE 22, POSTFACH 86 04 20, D-81679 MUNICH, GERMANY SN 0044-3093 J9 Z METALLKD JI Z. Metallk. PD JUL PY 2001 VL 92 IS 7 BP 707 EP 711 PG 5 WC Metallurgy & Metallurgical Engineering SC Metallurgy & Metallurgical Engineering GA 460VV UT WOS:000170317800013 ER PT J AU Huh, MY Engler, O AF Huh, MY Engler, O TI Effect of intermediate annealing on texture, formability and ridging of 17%Cr ferritic stainless steel sheet SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article DE ferritic stainless steal; ridging; intermediate annealing; rolling; recrystallization; selective particle drag ID LOW-CARBON STEEL; RECRYSTALLIZATION TEXTURES; ROLLING TEXTURES; GRAIN-BOUNDARIES; BCC METALS; IF-STEEL; DEFORMATION; ORIENTATION; GRADIENTS; EVOLUTION AB In order to improve the formability of ferritic stainless steel (FSS) sheets, the crystallographic texture of the sheets was modified by way of an intermediate annealing (IA) during the cold rolling. In the as-received hot band pronounced through-thickness texture gradients with a strong rotated cube orientation in the sheet center layer were observed. This strong initial texture has an impact on the texture and the resulting properties, including the undesired appearance of ridging, in the final recrystallized sheet. Instead of forming the {111}//ND gamma -fiber texture typical of recrystallized low-carbon steel sheets, the recrystallization texture was notably shifted towards {334}< 483 >. Introduction of an intermediate anneal during the cold rolling led to a weaker, more typical bcc rolling texture with less pronounced texture gradients. Accordingly, recrystallization gave rise to the characteristic gamma -fiber texture. The evolution of the different rolling textures is interpreted by means of texture simulations based on the Taylor deformation theory. The recrystallization textures are explained in terms of a preferred nucleation of recrystallization at the preexisting grain boundaries and a subsequent growth selection. The improvement in sheet formability through the IA is demonstrated by means of analysis of the R-values. Ridging is assessed through surface profile measurements. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Korea Univ, Div Mat Sci & Engn, Seoul 136701, South Korea. Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. RP Korea Univ, Div Mat Sci & Engn, Seoul 136701, South Korea. EM myhuh@mail.korea.ac.kr NR 49 TC 87 Z9 116 U1 4 U2 29 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 JUN 30 PY 2001 VL 308 IS 1-2 BP 74 EP 87 DI 10.1016/S0921-5093(00)01995-X PG 14 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 429FQ UT WOS:000168505700011 ER PT J AU Shen, YL Abeyta, MC Fang, HE AF Shen, YL Abeyta, MC Fang, HE TI Microstructural changes in eutectic tin-lead alloy due to severe bending SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article DE microstructural changes; severe bending; tin-lead alloy ID 63SN37PB SOLDER JOINTS; FATIGUE AB Severe plastic deformation in an eutectic tin-lead alloy is studied by imposing fast bending at room temperature, in an attempt to examine the microstructural response in the absence of thermally activated diffusion processes. A change in microstructure due to this purely mechanically imposed load is observed: the tin-rich matrix phase appears to be extruded out of the narrow region between neighboring layers of the lead-rich phase and alterations in the colony structure occur. A micromechanism is proposed to rationalize the experimental observations. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ New Mexico, Dept Mech Engn, Albuquerque, NM 87131 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Shen, YL (reprint author), Univ New Mexico, Dept Mech Engn, Albuquerque, NM 87131 USA. RI Shen, Yu-Lin/C-1942-2008 NR 18 TC 8 Z9 8 U1 0 U2 1 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0921-5093 J9 MAT SCI ENG A-STRUCT JI Mater. Sci. Eng. A-Struct. Mater. Prop. Microstruct. Process. PD JUN 30 PY 2001 VL 308 IS 1-2 BP 288 EP 291 DI 10.1016/S0921-5093(01)00919-4 PG 4 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 429FQ UT WOS:000168505700035 ER PT J AU Sheldon, ES Annis, J Bohringer, H Fischer, P Frieman, JA Joffre, M Johnston, D McKay, TA Miller, C Nichol, RC Stebbins, A Voges, W Anderson, SF Bahcall, NA Brinkmann, J Brunner, R Csabai, I Fukugita, M Hennessy, GS Ivezic, Z Lupton, RH Munn, JA Pier, JR York, DG AF Sheldon, ES Annis, J Bohringer, H Fischer, P Frieman, JA Joffre, M Johnston, D McKay, TA Miller, C Nichol, RC Stebbins, A Voges, W Anderson, SF Bahcall, NA Brinkmann, J Brunner, R Csabai, I Fukugita, M Hennessy, GS Ivezic, Z Lupton, RH Munn, JA Pier, JR York, DG TI Weak-lensing measurements of 42 SDSS/RASS galaxy clusters SO ASTROPHYSICAL JOURNAL LA English DT Article DE dark matter; galaxies : clusters : general; gravitational lensing; large-scale structure of universe; X-rays : general ID DIGITAL SKY SURVEY; MASS-DISTRIBUTION; REDSHIFT SURVEY; DISTRIBUTIONS; CATALOG AB We pwresent a lensing study of 42 galaxy clusters imaged in Sloan Digital Sky Survey (SDSS) commissioning data. Cluster candidates are selected optically from SDSS imaging data and confirmed for this study by matching to X-ray sources found independently in the ROSAT All-Sky Survey (RASS). Five-color SDSS photometry is used to make accurate (Deltaz = 0.018) photometric redshift estimates that are used to rescale and combine the lensing measurements. The mean shear from these clusters is detected to 2 h(-1) Mpc at the 7 sigma level, corresponding to a mass within that radius of (4.2 +/- 0.6) x 10(14) h(-1) M-.. The shear profile is well fitted by a power law with index -0.9 +/- 0.3, consistent with that of an isothermal density profile. Clusters are divided by X-ray luminosity into two subsets, with mean of L-X (0.14 +/- 0.03) x 10(44) and (1.0 +/- 0.09) x 10(44) h(-2) ergs s(-1). The average lensing signal is converted to a projected mass density based on fits to isothermal density profiles. From this we calculate a mean r(500) (the radius at which the mean density falls to 500 times the critical density) and M( 2B, We prove that chaotic advection modelled by the Baker map enhances the productivity of the reaction which is due to the fact that the reaction kinetics is catalysed by the fractal unstable manifold of the chaotic set of the reaction-free dynamics. The results are compared with phenomenological theories of active advection. C1 Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Los Alamos Natl Lab, Ctr Nonlinear Studies, Los Alamos, NM 87545 USA. Budapest Univ Technol & Econ, Dept Struct Mech, H-1521 Budapest, Hungary. Univ Calif San Diego, Scripps Inst Oceanog, Marine Phys Lab, La Jolla, CA 92093 USA. Eotvos Lorand Univ, Inst Theoret Phys, H-1518 Budapest, Hungary. RP Toroczkai, Z (reprint author), Los Alamos Natl Lab, Div Theoret, POB 1663, Los Alamos, NM 87545 USA. EM toro@lanl.gov; karolyi@tas.me.bme.hu; apentek@ucsd.edu; tel@poe.elte.hu RI Toroczkai, Zoltan/A-3421-2008; Karolyi, Gyorgy/A-5073-2008; OI Toroczkai, Zoltan/0000-0002-6602-2849; Karolyi, Gyorgy/0000-0002-1021-9554 NR 17 TC 11 Z9 11 U1 2 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0305-4470 J9 J PHYS A-MATH GEN JI J. Phys. A-Math. Gen. PD JUN 29 PY 2001 VL 34 IS 25 BP 5215 EP 5235 PG 21 WC Physics, Multidisciplinary; Physics, Mathematical SC Physics GA 452DN UT WOS:000169842000006 ER PT J AU Yusim, K Peeters, M Pybus, OG Bhattacharya, T Delaporte, E Mulanga, C Muldoon, M Theiler, J Korber, B AF Yusim, K Peeters, M Pybus, OG Bhattacharya, T Delaporte, E Mulanga, C Muldoon, M Theiler, J Korber, B TI Using human immunodeficiency virus type 1 sequences to infer historical features of the acquired immune deficiency syndrome epidemic and human immunodeficiency virus evolution SO PHILOSOPHICAL TRANSACTIONS OF THE ROYAL SOCIETY OF LONDON SERIES B-BIOLOGICAL SCIENCES LA English DT Article; Proceedings Paper CT Discussion Meeting on the Orgins of HIV and the AIDS Epidemic CY SEP 11-12, 2000 CL ROYAL SOCIETY, LONDON, ENGLAND HO ROYAL SOCIETY DE HIV-1; coalescent theory; molecular clock; evolution ID SYNDROME AIDS; HIV TYPE-1; TRANSMISSION HISTORY; CENTRAL-AFRICA; PHYLOGENETIC TREES; MAXIMUM-LIKELIHOOD; GENETIC DIVERSITY; PAN-TROGLODYTES; GENERATION TIME; IN-VIVO AB In earlier work, human immunodeficiency virus type 1 (HIV-1) sequences were analysed to estimate the timing of the ancestral sequence of the main group of HIV-1, the virus that is responsible for the acquired immune deficiency syndrome pandemic, yielding a best estimate of 1931 (95% confidence interval of 1915-1941). That work will be briefly reviewed, outlining how phylogenetic tools were extended to incorporate improved evolutionary models, how the molecular clock model was adapted to incorporate variable periods of latency, and how the approach was validated by correctly estimating the timing of two historically documented dates. The advantages, limitations, and assumptions of the approach will be summarized, with particular consideration of the implications of branch length uncertainty and recombination. We have recently undertaken new phylogenetic analysis of an extremely diverse set of human immunodeficiency virus envelope sequences from the Democratic Republic of the Congo (the DRC, formerly Zaire). This analysis both corroborates and extends the conclusions of our original study. Coalescent methods were used to infer the demographic history of the HIV-1 epidemic in the DRC, and the results suggest an increase in the exponential growth rate of the infected population through time. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Santa Fe Inst, Santa Fe, NM 87501 USA. Inst Rech Dev, Retrovirus Lab, F-34032 Montpellier, France. Univ Oxford, Dept Zool, Oxford OX1 3PS, England. CHU Montpellier, F-34295 Montpellier, France. Univ Manchester, Inst Sci & Technol, Manchester M60 1QD, Lancs, England. RP Yusim, K (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. RI Muldoon, Mark/C-7505-2009; pybus, oliver/B-2640-2012; Bhattacharya, Tanmoy/J-8956-2013; OI Bhattacharya, Tanmoy/0000-0002-1060-652X; Pybus, Oliver/0000-0002-8797-2667; Muldoon, Mark/0000-0002-5004-7195; Korber, Bette/0000-0002-2026-5757 NR 73 TC 49 Z9 51 U1 0 U2 4 PU ROYAL SOC LONDON PI LONDON PA 6 CARLTON HOUSE TERRACE, LONDON SW1Y 5AG, ENGLAND SN 0962-8436 J9 PHILOS T ROY SOC B JI Philos. Trans. R. Soc. Lond. Ser. B-Biol. Sci. PD JUN 29 PY 2001 VL 356 IS 1410 BP 855 EP 866 DI 10.1098/rstb.2001.0859 PG 12 WC Biology SC Life Sciences & Biomedicine - Other Topics GA 448PW UT WOS:000169636700014 PM 11405933 ER PT J AU Burr, T Hyman, JM Myers, G AF Burr, T Hyman, JM Myers, G TI The origin of acquired immune deficiency syndrome: Darwinian or Lamarckian? SO PHILOSOPHICAL TRANSACTIONS OF THE ROYAL SOCIETY OF LONDON SERIES B-BIOLOGICAL SCIENCES LA English DT Article; Proceedings Paper CT Discussion Meeting on the Orgins of HIV and the AIDS Epidemic CY SEP 11-12, 2000 CL ROYAL SOCIETY, LONDON, ENGLAND HO ROYAL SOCIETY DE HIV; AIDS; phylogenetic analysis; coalescent theory; synchronization ID IMMUNODEFICIENCY-VIRUS; AIDS; POPULATIONS; INFECTION; SEQUENCES; HISTORY AB The subtypes of human immunodeficiency virus type 1 (HIV-1) group M exhibit a remarkable similarity in their between-subtype distances, which we refer to as high synchrony. The shape of the phylogenetic tree of these subtypes is referred to as a sunburst to distinguish it from a simple star phylogeny Neither a sunburst pattern nor a comparable degree of symmetry is seen in a natural process such as in feline immunodeficiency virus evolution. We therefore have undertaken forward-process simulation studies employing coalescent theory to investigate whether such highly synchronized subtypes could be readily produced by natural Darwinian evolution. The forward model includes both classical (macro) and molecular (micro) epidemiological components. HIV-1 group M subtype synchrony is quantified using the standard deviation of the between-subtype distances and the average of the within-subtype distances. Highly synchronized subtypes and a sunburst phylogeny are not observed in our simulated data, leading to the conclusion that a quasi-Lamarckian, punctuated event occurred. The natural transfer theory for the origin of human acquired immune deficiency syndrome (AIDS) cannot easily be reconciled with these findings and it is as if a recent non-Darwinian process took place coincident with the rise of AIDS in Africa. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Burr, T (reprint author), Univ Calif Los Alamos Natl Lab, Mail Stop E541, Los Alamos, NM 87545 USA. NR 25 TC 9 Z9 9 U1 0 U2 1 PU ROYAL SOC LONDON PI LONDON PA 6 CARLTON HOUSE TERRACE, LONDON SW1Y 5AG, ENGLAND SN 0962-8436 J9 PHILOS T ROY SOC B JI Philos. Trans. R. Soc. Lond. Ser. B-Biol. Sci. PD JUN 29 PY 2001 VL 356 IS 1410 BP 877 EP 887 DI 10.1098/rstb.2001.0864 PG 11 WC Biology SC Life Sciences & Biomedicine - Other Topics GA 448PW UT WOS:000169636700016 PM 11405935 ER PT J AU Richter, B AF Richter, B TI DOE's support of the Sloan Digital Sky Survey SO SCIENCE LA English DT Letter C1 Stanford Linear Accelerator Ctr, Menlo Park, CA 94025 USA. RP Richter, B (reprint author), Stanford Linear Accelerator Ctr, Menlo Park, CA 94025 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 USA SN 0036-8075 J9 SCIENCE JI Science PD JUN 29 PY 2001 VL 292 IS 5526 BP 2432 EP 2432 PG 1 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 448YU UT WOS:000169658200018 PM 11441878 ER PT J AU Chakoumakos, BC Sales, BC Mandrus, DG AF Chakoumakos, BC Sales, BC Mandrus, DG TI Structural disorder and magnetism of the semiconducting clathrate Eu8Ga16Ge30 SO JOURNAL OF ALLOYS AND COMPOUNDS LA English DT Article DE atomic displacement parameters; semiconductor clathrate; ferromagnet; neutron diffraction; Eu8Ga16Ge30; Ba8Ga16Ge30 ID THERMAL-CONDUCTIVITY; LAFE4P12 STRUCTURE; ANTIMONIDES; EARTH; GE AB The temperature dependence of the atomic displacement parameters for an isotopically enriched Eu8Ga16Ge30 crystal determined from refinements of neutron diffraction data show the anomalously large values for the Eu atom in the large cage persist from 295 to 12 K. The Eu site in the large cage is modeled by splitting it into four fractionally occupied positions, displaced 0.4 Angstrom from the cage center. Fourier maps of this Eu site support this view in showing residual nuclear density with distinct peaks in the directions of the split-atom positions, and lesser density at the cage center position. The Ga and Ge atoms appear to be fully disordered on the three distinct framework sites. In comparing the isostructural X8Ga16Ge30 (X=Eu, Sr, Ba) compounds, the positional disorder around the large cage site increases progressively with decreasing size of the caged atom. Below 35 K, Eu8Ga16Ge30 orders ferromagnetically, with the preferred direction of the Eu moments along (100). The projected saturation value of the Eu moment, 7 mu (B), equals the free ion value. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Chakoumakos, BC (reprint author), Oak Ridge Natl Lab, Div Solid State, POB 2008, Oak Ridge, TN 37831 USA. RI Mandrus, David/H-3090-2014; Chakoumakos, Bryan/A-5601-2016 OI Chakoumakos, Bryan/0000-0002-7870-6543 NR 22 TC 94 Z9 94 U1 3 U2 18 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0925-8388 J9 J ALLOY COMPD JI J. Alloy. Compd. PD JUN 28 PY 2001 VL 322 IS 1-2 BP 127 EP 134 DI 10.1016/S0925-8388(01)01169-0 PG 8 WC Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering GA 444QT UT WOS:000169411600025 ER PT J AU Gibson, JK Haire, RG AF Gibson, JK Haire, RG TI Synthesis and investigation of plutonium oxide cluster ions: PuxOy+ (x <= 18) SO JOURNAL OF ALLOYS AND COMPOUNDS LA English DT Article DE plutonium; actinide clusters; plutonium oxidation states; laser ablation; mass spectrometry; cerium ID GAS-PHASE REACTIONS; LASER-ABLATION; ORGANOMETALLIC CHEMISTRY; MASS-SPECTRA; ALKENES; WATER AB The plutonium-oxygen system is fundamentally and technologically important. The primary goal of the present study was to prepare and carry out initial chemical studies on gas-phase plutonium oxide cluster ions, which would contribute to the general understanding of PuOx chemistry. In this effort, several plutonium oxide, oxide-hydroxide and hydroxide cluster ions, PuxOy(OH)(z)(+) were synthesized by pulsed laser ablation of hydrated plutonium oxalate in vacuum. Cerium was studied for comparison, and a chemically less diversified oxide cluster system was observed. The large variety of PuxOy(OH)(z)(+) compositions found is attributed to the accessibility of multiple oxidation states for Pu, and the results demonstrate the feasibility of preparing clusters with diverse stoichiometries and variable plutonium oxidation states. These clusters may be studied by various gas-phase techniques to illuminate the behavior of plutonium as a function of key variables, such as oxidation state, structure/coordination and bonding. In addition, some gas-phase reaction studies were carried out and at least one significant cluster reaction product with dimethylether was identified. This result demonstrates the desirability of studying plutonium cluster chemistry in ion traps where longer residence times, and more ion-molecule collisions will result in greater reaction efficiencies. The largest primary oxide cluster identified here comprised six Pu atoms, but two distinctive 'magic number' clusters were also produced, which incorporated 16 and 18 Pu atoms, respectively. These 'magic number' clusters suggest that special stabilities obtain for these species and that it may be possible to prepare plutonium oxide 'nanocrystals' in the gas phase for examination by techniques complementary to those applicable to bulk materials. The plutonium cluster compositions and abundances observed in this work are discussed in the context of the oxidation states, structures, and bonding exhibited by plutonium. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Gibson, JK (reprint author), Oak Ridge Natl Lab, Div Chem & Analyt Sci, POB 2008, Oak Ridge, TN 37831 USA. NR 31 TC 11 Z9 11 U1 2 U2 19 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0925-8388 J9 J ALLOY COMPD JI J. Alloy. Compd. PD JUN 28 PY 2001 VL 322 IS 1-2 BP 143 EP 152 DI 10.1016/S0925-8388(01)01178-1 PG 10 WC Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering GA 444QT UT WOS:000169411600027 ER PT J AU Wang, Z Hemmer, SL Friedrich, DM Joly, AG AF Wang, Z Hemmer, SL Friedrich, DM Joly, AG TI Anthracene as the origin of the red-shifted emission from commercial zone-refined phenanthrene sorbed on mineral surfaces SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID LIFETIME DISTRIBUTION ANALYSIS; SILICA-GEL SURFACES; ORGANIC-CHEMICALS; REACTIVITY MODEL; SORPTION; SEDIMENTS; SOILS; CONTAMINANTS; PHOTOPHYSICS; SEQUESTRATION AB The origin of the red-shifted fluorescence emission spectra observed for commercial zone-refined phenanthrene (purity 99.5+%) in concentrated cyclohexane solution and as sorbates on porous silica at high loading levels was studied by absorption and fluorescence spectroscopy as well as fluorescence quenching measurements, The absorption and fluorescence spectra indicate that a small amount of anthracene is present in the zone-refined phenanthrene. In concentrated phenanthrene solution and highly phenanthrene-loaded porous silica, excitation energy transfer from phenanthrene to the anthracene: impurity results in the reduction of the phenanthrene fluorescence intensity and the appearance of the anthracene fluorescence emission at longer wavelength. A Stern-Volmer plot for quenching of phenanthrene fluorescence by anthracene in cyclohexane indicates both dynamic and static energy transfer mechanisms. For phenanthrene sorbed on mineral surfaces, the dynamic pathway is limited. Therefore, the appearance of anthracene fluorescence due to energy transfer from excited phenanthrene can serve as a spectral probe for polyaromatic hydrocarbon (PAH) aggregation and association on mineral surfaces. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Wang, Z (reprint author), Pacific NW Natl Lab, Richland, WA 99352 USA. RI Wang, Zheming/E-8244-2010 OI Wang, Zheming/0000-0002-1986-4357 NR 33 TC 6 Z9 6 U1 1 U2 7 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 JUN 28 PY 2001 VL 105 IS 25 BP 6020 EP 6023 DI 10.1021/jp003983v PG 4 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 446VJ UT WOS:000169534600009 ER PT J AU Paddison, SJ Pratt, LR Zawodzinski, TA AF Paddison, SJ Pratt, LR Zawodzinski, TA TI Variation of the dissociation constant of triflic acid with hydration SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID STATISTICAL-MECHANICAL MODEL; WATER TRANSPORT; HYDROXIDE ION; NAFION(R); SOLVATION; SIMULATION; MEMBRANES; PROTON AB The variation of the acid dissociation equilibrium of trifluoromethane sulfonic acid in dilute aqueous solution along the liquid-vapor dissociation curve is treated by a dielectric hydration model. The computational results indicate that the dissociation equilibrium becomes unfavorable from the point of view of the free energy change as temperature is increased above 500 K where the solvent density is less than 85% of the triple-point density. These results give additional perspective for the view that insufficient hydration can result in incomplete proton dissociation from sulfonic acid headgroups in Nafion membranes. C1 Motorola Inc, Computat Mat Grp, Los Alamos, NM 87544 USA. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. RP Paddison, SJ (reprint author), Motorola Inc, Computat Mat Grp, Los Alamos Res Pk, Los Alamos, NM 87544 USA. EM s.paddison@motorola.com RI Pratt, Lawrence/H-7955-2012; Paddison, Stephen/B-2935-2014 OI Pratt, Lawrence/0000-0003-2351-7451; NR 29 TC 40 Z9 40 U1 1 U2 16 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 JUN 28 PY 2001 VL 105 IS 25 BP 6266 EP 6268 DI 10.1021/jp010737q PG 3 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 446VJ UT WOS:000169534600039 ER PT J AU Petrik, NG Alexandrov, AB Vall, AI AF Petrik, NG Alexandrov, AB Vall, AI TI Interfacial energy transfer during gamma radiolysis of water on the surface of ZrO2 and some other oxides SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID SELF-TRAPPED EXCITONS; STABILIZED ZIRCONIA; RADIATION CORROSION; NUCLEAR-REACTORS; FUEL-ELEMENTS; THIN-FILMS; HYDROGEN; CRYSTALS; EXCITATION; MODEL AB The effect of an oxide interface on Co-60 gamma radiolysis of water molecules was studied. On the basis of the molecular hydrogen yield when compared with the radiolysis of the control ampules without oxides, all the tested materials can be generally classified into three groups: I. Oxides that lower the H-2 yield (MnO2, Co3O4, CuO, and Fe2O3); II. Oxides with H-2 yields that are close to C values obtained in control experiments (MgO, CaO, SrO, BaO, ZnO, CdO, Cu2O, NiO, Cr2O3, Al2O3, CeO2, SiO2, TiO2, Nb2O5 and WO3); and III. Oxides that can increase the H-2 yield as compared with the radiolysis of water without oxides (Ga2O3, Y2O3, La2O3, Nd2O3, Sm2O3, Eu2O3, Gd2O3, Yb2O3, Er2O3, HfO2, and ZrO2). For the third group, the H-2 yield can be much greater than for the homogeneous process due to effective energy transfer at the oxide/water interface. There are several parameters, such as the oxide band-gap, water adsorption form, and energy migration distance that can collectively contribute to "enhanced" radiolysis yields at interfaces. We present data of "effective" H-2 yield vs band-gap (Eg) energy that show a resonant maximum at Eg = 5 eV. This maximum corresponds to the energy of H-OH bond in the water molecule (5.1 eV). By varying the ZrO2 specific area within a 0.02-12 m(2) g(-1) range, we also demonstrated that the H-2 yield per unit area of the crystal surface is constant. Doping the ZrO2 bulk with Nb5+ and Li+ ions has a remarkable effect on the H-2 yield from the surface. We estimated the energy migration distance to be similar to5 nm. Thermostimulated luminescence was used to probe the nature of the migrating electronic excitations in ZrO2. Finally, we propose a mechanism for the adsorbed water radiolysis based on the migration of excitons to the surface and their resonant coupling with the H2O/oxide adsorption complex. C1 Pacific NW Natl Lab, WR Wiley Environm Mol Sci Lab, Richland, WA 99352 USA. All Russian Project 7 Res Inst Complex Power Tech, St Petersburg 197228, Russia. Lensovet Technol Inst, St Petersburg 198013, Russia. RP Petrik, NG (reprint author), Pacific NW Natl Lab, WR Wiley Environm Mol Sci Lab, POB 999, Richland, WA 99352 USA. RI Petrik, Nikolay/G-3267-2015 OI Petrik, Nikolay/0000-0001-7129-0752 NR 81 TC 75 Z9 75 U1 6 U2 51 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 JUN 28 PY 2001 VL 105 IS 25 BP 5935 EP 5944 DI 10.1021/jp004440o PG 10 WC Chemistry, Physical SC Chemistry GA 446VM UT WOS:000169534900015 ER PT J AU Beuhler, RJ Rao, RM Hrbek, J White, MG AF Beuhler, RJ Rao, RM Hrbek, J White, MG TI Study of the partial oxidation of methanol to formaldehyde on a polycrystalline Ag foil SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID CATALYTIC CONDITIONS; SILVER; OXYGEN; DIFFUSION AB A study of the partial oxidation reaction of methanol to formaldehyde has been carried out on the surface of an oxygen permeable, Ag-membrane. Surface oxygen species are formed on the high vacuum side of the Ag-foil by diffusion of O atoms generated by dissociative adsorption on the high pressure side at temperatures > 500 K. Methanol pressures were kept sufficiently low (less than or equal to 10(-5) Torr) to ensure collision free sampling of the products using electron-impact mass spectrometry. Starting with a new Ag-foil, reaction rates were found to increase over time, with maximum rates achieved after activation times of several hours. Activation is accompanied by significant changes in membrane morphology. For a methanol pressure of 1 x 10(-6) Torr, the maximum rate of formaldehyde formation is 7 x 10(14) mol/s-cm(2) at 900 K and only decreases by a factor of 2 as the foil temperature is reduced to 300 K. Reaction at room temperature is attributed to the high diffusion rate of O atoms dissolved in the bulk which maintains the surface oxygen concentration sufficiently high to achieve reaction rates of 5 x 10(14) mol/s-cm2 for hours when the methanol pressure is held at 2 x 10-6 Torr. Attempts to titrate all the membrane O atoms through reaction with methanol were unsuccessful, and suggest that the loading must be greater than 10(19) O atoms/gram of Ag. C1 Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. RP White, MG (reprint author), Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. RI Hrbek, Jan/I-1020-2013 NR 20 TC 7 Z9 8 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 JUN 28 PY 2001 VL 105 IS 25 BP 5950 EP 5956 DI 10.1021/jp010134e PG 7 WC Chemistry, Physical SC Chemistry GA 446VM UT WOS:000169534900017 ER PT J AU Seth, M Dyall, KG Shepard, R Wagner, A AF Seth, M Dyall, KG Shepard, R Wagner, A TI The calculation of f-f spectra of lanthanide and actinide ions by the MCDF-CI method SO JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS LA English DT Article ID COUPLED-CLUSTER METHOD; RARE-EARTH IONS; ENERGY-LEVEL ANALYSIS; ELECTRON CORRELATION; MULTIPLET TERMS; CONFIGURATION; ABINITIO; PR-3+; PR+3; 4F2 AB The calculation of f-f spectra of lanthanide and actinide ions by the multiconfiguration Dirac-Fock configuration interaction (MCDF-CI) method is discussed. The U4+, Pr3+, NP3+, Pm3+, Am3+ and Eu3+ ions are considered in detail. The effects of the different classes of excitation included and the flexibility of the basis of one-particle functions used on the calculated spectra are discussed. Breit and size-extensivity corrections are also considered. Reasonably accurate (errors < 500 cm(-1)) spectra of U4+ and Pr3+ are achieved fairly readily and the best spectra of these ions are comparable with the most accurate published calculations, The best spectra of the other ions are less accurate but are in significantly better agreement with experiment than any previous ab initio calculation. C1 Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. Eloret Corp, Sunnyvale, CA 94087 USA. RP Seth, M (reprint author), Univ Calgary, Dept Chem, Univ Dr 2500, Calgary, AB T2N 1N4, Canada. NR 34 TC 22 Z9 22 U1 2 U2 8 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 JUN 28 PY 2001 VL 34 IS 12 BP 2383 EP 2406 DI 10.1088/0953-4075/34/12/307 PG 24 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 451WP UT WOS:000169825700009 ER PT J AU Stancil, PC Turner, AR Cooper, DL Schultz, DR Rakovic, MJ Fritsch, W Zygelman, B AF Stancil, PC Turner, AR Cooper, DL Schultz, DR Rakovic, MJ Fritsch, W Zygelman, B TI Electron capture in collisions of S4+ with atomic hydrogen SO JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS LA English DT Article ID MULTIPLY CHARGED IONS; CROSS-SECTIONS; X-RAY; PRECIPITATION; SPECTROSCOPY; SCATTERING; ENERGIES; EMISSION; HELIUM; AURORA AB Charge transfer processes due to collisions of ground state S4+(3s(2) S-1) ions with atomic hydrogen are investigated for energies between 1 meV u(-1) and 10 MeV u(-1) using the quantum mechanical molecular-orbital close-coupling (MOCC), atomic-orbital close-coupling, classical trajectory Monte Carlo (CTMC) and continuum distorted wave methods. The MOCC calculations utilize ab initio adiabatic potentials and nonadiabatic radial coupling matrix elements obtained with the spin-coupled valence-bond approach. A number of variants of the CTMC approach were explored, including different momentum and radial distributions for the initial state, as well as effective charge and quantum-defect models to determine the corresponding quantum state after capture into final partially stripped S3+ excited classical states. Hydrogen target isotope effects are explored and rate coefficients for temperatures between 100 and 10(6) K are also presented. C1 Univ Georgia, Dept Phys & Astron, Athens, GA 30602 USA. Univ Liverpool, Dept Chem, Liverpool L69 7ZD, Merseyside, England. Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. Hahn Meitner Inst Kernforsch Berlin GmbH, Theoret Phys Abt, D-14109 Berlin, Germany. Univ Nevada, Dept Phys, Las Vegas, NV 89154 USA. RP Stancil, PC (reprint author), Univ Georgia, Dept Phys & Astron, Athens, GA 30602 USA. RI Fritsch, Wolfgang/B-3412-2009 NR 42 TC 15 Z9 15 U1 0 U2 2 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 JUN 28 PY 2001 VL 34 IS 12 BP 2481 EP 2504 PG 24 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 451WP UT WOS:000169825700015 ER PT J AU Chekanov, S Derrick, M Krakauer, D Magill, S Musgrave, B Pellegrino, A Repond, J Stanek, R Yoshida, R Mattingly, MCK Antonioli, P Bari, G Basile, M Bellagamba, L Boscherini, D Bruni, A Bruni, G Romeo, GC Cifarelli, L Cindolo, F Contin, A Corradi, M De Pasquale, S Giusti, P Iacobucci, G Levi, G Margotti, A Massam, T Nania, R Palmonari, F Pesci, A Sartorelli, G Zichichi, A Aghuzumtsyan, G Brock, I Goers, S Hartmann, H Hilger, E Irrgang, P Jakob, HP Kappes, A Katz, UF Kerger, R Kind, O Paul, E Rautenberg, J Schnurbusch, H Stifutkin, A Tandler, J Voss, KC Weber, A Wieber, H Bailey, DS Brook, NH Cole, JE Foster, B Heath, GP Heath, HF Robins, S Rodrigues, E Scott, J Tapper, RJ Capua, M Mastroberardino, A Schioppa, M Susinno, G Jeoung, HY Kim, JY Lee, JH Lim, IT Ma, KJ Pac, MY Caldwell, A Helbich, M Liu, W Liu, X Mellado, B Paganis, S Sampson, S Schmidke, WB Sciulli, F Chwastowski, J Eskreys, A Figiel, J Klimek, K Olkiewicz, K Przybycien, MB Stopa, P Zawiejski, L Bednarek, B Jelen, K Kisielewska, D Kowal, AM Kowalski, T Przybycien, M Rulikowska-Zarebska, E Suszycki, L Szuba, D Kotanski, A Bauerdick, LAT Behrens, U Borras, K Chiochia, V Crittenden, J Dannheim, D Desler, K Drews, G Fox-Murphy, A Fricke, U Geiser, A Goebel, F Gottlicher, P Graciani, R Haas, T Hain, W Hartner, GF Hebbel, K Hillert, S Koch, W Kotz, U Kowalski, H Labes, H Lohr, B Mankel, R Martens, J Martinez, M Milite, M Moritz, M Notz, D Petrucci, MC Polini, A Savin, AA Schneekloth, U Selonke, F Stonjek, S Wolf, G Wollmer, U Whitmore, JJ Wichmann, R Youngman, C Zeuner, W Coldewey, C Viani, ALD Meyer, A Schlenstedt, S Barbagli, G Gallo, E Parenti, A Pelfer, PG Bamberger, A Benen, A Coppola, N Markun, P Raach, H Wolfle, S Bell, M Bussey, PJ Doyle, AT Glasman, C Lee, SW Lupi, A McCance, GJ Saxon, DH Skillicorn, IO Bodmann, B Gendner, N Holm, U Salehi, H Wick, K Yildirim, A Ziegler, A Carli, T Garfagnini, A Gialas, I Lohrmann, E Foudas, C Goncalo, R Long, KR Metlica, F Miller, DB Tapper, AD Walker, R Cloth, P Filges, D Ishii, T Kuze, M Nagano, K Tokushuku, K Yamada, S Yamazaki, Y Barakbaev, AN Boos, EG Pokrovskiy, NS Zhautykov, BO Ahn, SH Lee, SB Park, SK Lim, H Son, D Barreiro, F Garcia, G Gonzalez, O Labarga, L del Peso, J Redondo, I Terron, J Vazquez, M Barbi, M Corriveau, F Padhi, S Stairs, DG Wing, M Tsurugai, T Antonov, A Bashkirov, V Danilov, P Dolgoshein, BA Gladkov, D Sosnovtsev, V Suchkov, S Dementiev, RK Ermolov, PF Golubkov, YA Katkov, II Khein, LA Korotkova, NA Korzhavina, IA Kuzmin, VA Levchenko, BB Lukina, OY Proskuryakov, AS Shcheglova, LM Solomin, AN Vlasov, NN Zotkin, SA Bokel, C Botje, M Engelen, J Grijpink, S Koffeman, E Kooijman, P Schagen, S van Sighem, A Tassi, E Tiecke, H Tuning, N Velthuis, JJ Vossebeld, J Wiggers, L de Wolf, E Brummer, N Bylsma, B Durkin, LS Gilmore, J Ginsburg, CM Kim, CL Ling, TY Boogert, S Cooper-Sarkar, AM Devenish, RCE Ferrando, J Grosse-Knetter, J Matsushita, T Rigby, M Ruske, O Sutton, MR Walczak, R Bertolin, A Brugnera, R Carlin, R Dal Corso, F Dusini, S Limentani, S Longhin, A Posocco, M Stanco, L Turcato, M Adamczyk, L Iannotti, L Oh, BY Saull, PRB Toothacker, WS Iga, Y D'Agostini, G Marini, G Nigro, A Cormack, C Hart, JC McCubbin, NA Epperson, D Heusch, C Sadrozinski, HFW Seiden, A Williams, DC Park, IH Pavel, N Abramowicz, H Dagan, S Gabareen, A Kananov, S Kreisel, A Levy, A Abe, T Fusayasu, T Kohno, T Umemori, K Yamashita, T Hamatsu, R Hirose, T Inuzuka, M Kitamura, S Matsuzawa, K Nishimura, T Arneodo, M Cartiglia, N Cirio, R Costa, M Ferrero, MI Maselli, S Monaco, V Peroni, C Ruspa, M Sacchi, R Solano, A Staiano, A Bailey, DC Fagerstroem, CP Galea, R Koop, T Levman, GM Martin, JF Mirea, A Sabetfakhri, A Butterworth, JM Gwenlan, C Hayes, ME Heaphy, EA Jones, TW Lane, JB West, BJ Ciborowski, J Ciesielski, R Grzelak, G Nowak, RJ Pawlak, JM Plucinski, P Smalska, B Sztuk, J Tymieniecka, T Ukleja, J Zakrzewski, JA Zarnecki, AF Adamus, M Deppe, O Eisenberg, Y Gladilin, LK Hochman, D Karshon, U Breitweg, J Chapin, D Cross, R Kcira, D Lammers, S Reeder, DD Smith, WH Deshpande, A Dhawan, S Hughes, VW Straub, PB Bhadra, S Catterall, CD Frisken, WR Hall-Wilton, R Khakzad, M Menary, S AF Chekanov, S Derrick, M Krakauer, D Magill, S Musgrave, B Pellegrino, A Repond, J Stanek, R Yoshida, R Mattingly, MCK Antonioli, P Bari, G Basile, M Bellagamba, L Boscherini, D Bruni, A Bruni, G Romeo, GC Cifarelli, L Cindolo, F Contin, A Corradi, M De Pasquale, S Giusti, P Iacobucci, G Levi, G Margotti, A Massam, T Nania, R Palmonari, F Pesci, A Sartorelli, G Zichichi, A Aghuzumtsyan, G Brock, I Goers, S Hartmann, H Hilger, E Irrgang, P Jakob, HP Kappes, A Katz, UF Kerger, R Kind, O Paul, E Rautenberg, J Schnurbusch, H Stifutkin, A Tandler, J Voss, KC Weber, A Wieber, H Bailey, DS Brook, NH Cole, JE Foster, B Heath, GP Heath, HF Robins, S Rodrigues, E Scott, J Tapper, RJ Capua, M Mastroberardino, A Schioppa, M Susinno, G Jeoung, HY Kim, JY Lee, JH Lim, IT Ma, KJ Pac, MY Caldwell, A Helbich, M Liu, W Liu, X Mellado, B Paganis, S Sampson, S Schmidke, WB Sciulli, F Chwastowski, J Eskreys, A Figiel, J Klimek, K Olkiewicz, K Przybycien, MB Stopa, P Zawiejski, L Bednarek, B Jelen, K Kisielewska, D Kowal, AM Kowalski, T Przybycien, M Rulikowska-Zarebska, E Suszycki, L Szuba, D Kotanski, A Bauerdick, LAT Behrens, U Borras, K Chiochia, V Crittenden, J Dannheim, D Desler, K Drews, G Fox-Murphy, A Fricke, U Geiser, A Goebel, F Gottlicher, P Graciani, R Haas, T Hain, W Hartner, GF Hebbel, K Hillert, S Koch, W Kotz, U Kowalski, H Labes, H Lohr, B Mankel, R Martens, J Martinez, M Milite, M Moritz, M Notz, D Petrucci, MC Polini, A Savin, AA Schneekloth, U Selonke, F Stonjek, S Wolf, G Wollmer, U Whitmore, JJ Wichmann, R Youngman, C Zeuner, W Coldewey, C Viani, ALD Meyer, A Schlenstedt, S Barbagli, G Gallo, E Parenti, A Pelfer, PG Bamberger, A Benen, A Coppola, N Markun, P Raach, H Wolfle, S Bell, M Bussey, PJ Doyle, AT Glasman, C Lee, SW Lupi, A McCance, GJ Saxon, DH Skillicorn, IO Bodmann, B Gendner, N Holm, U Salehi, H Wick, K Yildirim, A Ziegler, A Carli, T Garfagnini, A Gialas, I Lohrmann, E Foudas, C Goncalo, R Long, KR Metlica, F Miller, DB Tapper, AD Walker, R Cloth, P Filges, D Ishii, T Kuze, M Nagano, K Tokushuku, K Yamada, S Yamazaki, Y Barakbaev, AN Boos, EG Pokrovskiy, NS Zhautykov, BO Ahn, SH Lee, SB Park, SK Lim, H Son, D Barreiro, F Garcia, G Gonzalez, O Labarga, L del Peso, J Redondo, I Terron, J Vazquez, M Barbi, M Corriveau, F Padhi, S Stairs, DG Wing, M Tsurugai, T Antonov, A Bashkirov, V Danilov, P Dolgoshein, BA Gladkov, D Sosnovtsev, V Suchkov, S Dementiev, RK Ermolov, PF Golubkov, YA Katkov, II Khein, LA Korotkova, NA Korzhavina, IA Kuzmin, VA Levchenko, BB Lukina, OY Proskuryakov, AS Shcheglova, LM Solomin, AN Vlasov, NN Zotkin, SA Bokel, C Botje, M Engelen, J Grijpink, S Koffeman, E Kooijman, P Schagen, S van Sighem, A Tassi, E Tiecke, H Tuning, N Velthuis, JJ Vossebeld, J Wiggers, L de Wolf, E Brummer, N Bylsma, B Durkin, LS Gilmore, J Ginsburg, CM Kim, CL Ling, TY Boogert, S Cooper-Sarkar, AM Devenish, RCE Ferrando, J Grosse-Knetter, J Matsushita, T Rigby, M Ruske, O Sutton, MR Walczak, R Bertolin, A Brugnera, R Carlin, R Dal Corso, F Dusini, S Limentani, S Longhin, A Posocco, M Stanco, L Turcato, M Adamczyk, L Iannotti, L Oh, BY Saull, PRB Toothacker, WS Iga, Y D'Agostini, G Marini, G Nigro, A Cormack, C Hart, JC McCubbin, NA Epperson, D Heusch, C Sadrozinski, HFW Seiden, A Williams, DC Park, IH Pavel, N Abramowicz, H Dagan, S Gabareen, A Kananov, S Kreisel, A Levy, A Abe, T Fusayasu, T Kohno, T Umemori, K Yamashita, T Hamatsu, R Hirose, T Inuzuka, M Kitamura, S Matsuzawa, K Nishimura, T Arneodo, M Cartiglia, N Cirio, R Costa, M Ferrero, MI Maselli, S Monaco, V Peroni, C Ruspa, M Sacchi, R Solano, A Staiano, A Bailey, DC Fagerstroem, CP Galea, R Koop, T Levman, GM Martin, JF Mirea, A Sabetfakhri, A Butterworth, JM Gwenlan, C Hayes, ME Heaphy, EA Jones, TW Lane, JB West, BJ Ciborowski, J Ciesielski, R Grzelak, G Nowak, RJ Pawlak, JM Plucinski, P Smalska, B Sztuk, J Tymieniecka, T Ukleja, J Zakrzewski, JA Zarnecki, AF Adamus, M Deppe, O Eisenberg, Y Gladilin, LK Hochman, D Karshon, U Breitweg, J Chapin, D Cross, R Kcira, D Lammers, S Reeder, DD Smith, WH Deshpande, A Dhawan, S Hughes, VW Straub, PB Bhadra, S Catterall, CD Frisken, WR Hall-Wilton, R Khakzad, M Menary, S CA Zeus Collaboration TI Study of the effective transverse momentum of partons in the proton using prompt photons in photoproduction at HERA SO PHYSICS LETTERS B LA English DT Article ID CENTRAL TRACKING DETECTOR; CROSS-SECTION; P(P)OVER-BAR COLLISIONS; ROOT-S=1.8 TEV; HADRON-COLLISIONS; MONTE-CARLO; ZEUS; DISTRIBUTIONS; CALORIMETER; HADROPRODUCTION AB The photoproduction of prompt photons, together with an accompanying jet, has been measured with the ZEUS detector at HERA using an integrated luminosity of 38.6 pb(-1). A study of the effective transverse momentum. (k(T)), of partons in the proton, as modelled within the framework of the PYTHIA Monte Carlo. gives a value of (k(T)) = 1.69 +/- 0.18(-0.20)(+0.18) GeV for the gammap centre-of-mass energy range 134 < W < 251 GeV. This result is in agreement with the previously observed trend in hadron-hadron scattering for (k(T)) to rise with interaction energy. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Argonne Natl Lab, Argonne, IL 60439 USA. Andrews Univ, Berrien Springs, MI 49104 USA. Univ Bologna, Bologna, Italy. Ist Nazl Fis Nucl, I-40126 Bologna, Italy. Univ Bonn, Inst Phys, D-5300 Bonn, Germany. Univ Bristol, HH Wills Phys Lab, Bristol BS8 1TL, Avon, England. Univ Calabria, Dept Phys, I-87036 Cosenza, Italy. Ist Nazl Fis Nucl, Cosenza, Italy. Chonnam Natl Univ, Kwangju, South Korea. Columbia Univ, Nevis Labs, New York, NY USA. Inst Nucl Phys, Krakow, Poland. Acad Min & Met, Fac Phys & Nucl Tech, Krakow, Poland. Jagiellonian Univ, Dept Phys, Krakow, Poland. DESY, D-2000 Hamburg, Germany. DESY, Zeuthen, Germany. Univ Florence, Florence, Italy. Ist Nazl Fis Nucl, I-50125 Florence, Italy. Univ Freiburg, Fak Phys, D-7800 Freiburg, Germany. Univ Glasgow, Dept Phys & Astron, Glasgow, Lanark, Scotland. Univ Hamburg, Inst Expt Phys 1, Hamburg, Germany. Univ Hamburg, Inst Expt Phys 2, D-2000 Hamburg, Germany. Univ London Imperial Coll Sci Technol & Med, High Energy Nucl Phys Grp, London, England. Forschungszentrum Julich, Inst Kernphys, D-5170 Julich, Germany. KEK, Inst Particle & Nucl Studies, Tsukuba, Ibaraki, Japan. Minist Educ & Sci Kazakhstan, Inst Phys & Technol, Alma Ata, Kazakhstan. Korea Univ, Seoul 136701, South Korea. Kyungpook Natl Univ, Taegu 702701, South Korea. Univ Autonoma Madrid, Dept Fis Teor, Madrid, Spain. McGill Univ, Dept Phys, Montreal, PQ, Canada. Meiji Gakuin Univ, Fac Gen Educ, Yokohama, Kanagawa, Japan. Moscow Engn Phys Inst, Moscow 115409, Russia. Moscow MV Lomonosov State Univ, Inst Nucl Phys, Moscow, Russia. NIKHEF, Amsterdam, Netherlands. Univ Amsterdam, Amsterdam, Netherlands. Ohio State Univ, Dept Phys, Columbus, OH 43210 USA. Univ Oxford, Dept Phys, Oxford, England. Univ Padua, Dipartimento Fis, Padua, Italy. Ist Nazl Fis Nucl, Padua, Italy. Penn State Univ, Dept Phys, University Pk, PA 16802 USA. Polytech Univ, Sagamihara, Kanagawa, Japan. Univ Roma La Sapienza, Dipartimento Fis, I-00185 Rome, Italy. Ist Nazl Fis Nucl, Rome, Italy. Rutherford Appleton Lab, Didcot OX11 0QX, Oxon, England. Univ Calif Santa Cruz, Santa Cruz, CA 95064 USA. Seoul Natl Univ, Seoul, South Korea. Univ Siegen, Fachbereich Phys, D-5900 Siegen, Germany. Tel Aviv Univ, Sch Phys, Raymond & Beverly Sackler Fac Exact Sci, IL-69978 Tel Aviv, Israel. Univ Tokyo, Dept Phys, Tokyo 113, Japan. Tokyo Metropolitan Univ, Dept Phys, Tokyo, Japan. Univ Turin, Dipartimento Fis Sperimentale, Turin, Italy. Ist Nazl Fis Nucl, I-10125 Turin, Italy. Univ Toronto, Dept Phys, Toronto, ON, Canada. UCL, Dept Phys & Astron, London, England. Warsaw Univ, Inst Expt Phys, Warsaw, Poland. Inst Nucl Studies, PL-00681 Warsaw, Poland. Weizmann Inst Sci, Dept Particle Phys, IL-76100 Rehovot, Israel. Univ Wisconsin, Dept Phys, Madison, WI 53706 USA. Yale Univ, Dept Phys, New Haven, CT USA. York Univ, Dept Phys, Toronto, ON M3J 2R7, Canada. RP Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Gladilin, Leonid/B-5226-2011; Solomin, Anatoly/C-3072-2016; Suchkov, Sergey/M-6671-2015; dusini, stefano/J-3686-2012; Goncalo, Ricardo/M-3153-2016; Graciani Diaz, Ricardo/I-5152-2016; Capua, Marcella/A-8549-2015; Wiggers, Leo/B-5218-2015; Tassi, Enrico/K-3958-2015; De Pasquale, Salvatore/B-9165-2008; Wing, Matthew/C-2169-2008; Bashkirov, Vladimir/A-4818-2008; Doyle, Anthony/C-5889-2009; Ferrando, James/A-9192-2012; Golubkov, Yury/E-1643-2012; Levchenko, B./D-9752-2012; Proskuryakov, Alexander/J-6166-2012; Dementiev, Roman/K-7201-2012; Katz, Uli/E-1925-2013 OI Gladilin, Leonid/0000-0001-9422-8636; dusini, stefano/0000-0002-1128-0664; Goncalo, Ricardo/0000-0002-3826-3442; Graciani Diaz, Ricardo/0000-0001-7166-5198; Capua, Marcella/0000-0002-2443-6525; Longhin, Andrea/0000-0001-9103-9936; PAGANIS, STATHES/0000-0002-1950-8993; Wiggers, Leo/0000-0003-1060-0520; De Pasquale, Salvatore/0000-0001-9236-0748; Doyle, Anthony/0000-0001-6322-6195; Ferrando, James/0000-0002-1007-7816; Katz, Uli/0000-0002-7063-4418 NR 42 TC 33 Z9 33 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 EI 1873-2445 J9 PHYS LETT B JI Phys. Lett. B PD JUN 28 PY 2001 VL 511 IS 1 BP 19 EP 32 DI 10.1016/S0370-2693(01)00615-3 PG 14 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 451PC UT WOS:000169809600003 ER PT J AU Cheng, HY Yang, KC AF Cheng, HY Yang, KC TI Charmless B -> VV decays in QCD factorization implications of recent B -> phi K* measurement SO PHYSICS LETTERS B LA English DT Article ID MESON DECAYS; WEAK DECAYS AB In the heavy quark limit, both vector mesons in the charmless B --> VV decay should have zero helicity and the corresponding amplitude is proportional to the form factor difference (A(1) - A(2)). The first observed charmless B --> VV mode, B --> phiK* indicates that the form factors A(1)(q(2)) and A(2)(q(2)) cannot be very similar at low q(2) as shown in some form-factor models. The approach of QCD-improved factorization implies that the nonfactorizable correction to each partial-wave or helicity amplitude is not the same: the effective parameters a(i) vary for different helicity amplitudes. The leading-twist nonfactorizable corrections to the transversely polarized amplitudes vanish in the chiral limit and hence it is necessary to take into account twist-3 distribution amplitudes of the vector meson in order to have renormalization scale and scheme independent predictions. Branching ratios of B --> VV decays are calculated in two different models for form factors, and the predicted decay rates are different by a factor of 1.5 similar to 2. Owing to the absence of (S - P)(S + P) penguin contributions to the W-emission amplitudes, tree-dominated decays tend to have larger branching ratios than the penguin-dominated ones. (C) 2001 Published by Elsevier Science B.V. C1 Acad Sinica, Inst Phys, Taipei 115, Taiwan. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Chung Yuan Christian Univ, Dept Phys, Chungli 320, Taiwan. RP Cheng, HY (reprint author), Acad Sinica, Inst Phys, Taipei 115, Taiwan. EM phcheng@quark.phy.bnl.gov NR 20 TC 72 Z9 72 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 J9 PHYS LETT B JI Phys. Lett. B PD JUN 28 PY 2001 VL 511 IS 1 BP 40 EP 48 DI 10.1016/S0370-2693(01)00606-2 PG 9 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 451PC UT WOS:000169809600005 ER PT J AU Shadle, LJ Monazam, ER Swanson, ML AF Shadle, LJ Monazam, ER Swanson, ML TI Coal gasification in a transport reactor SO INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH LA English DT Article ID FLUIDIZED-BED COMBUSTION; REACTIVITY; STEAM; CHAR; ENTRAINMENT; FREEBOARD; SOLIDS; MODEL; CO2 AB An advanced transport reactor gasifier was operated using three different coals: Illinois #6 bituminous, Wyodak Powder River Basin subbituminous, and a Sufco Utah bituminous coals. A steady-state model was developed to evaluate the relative contributions of coal combustion and gasification of coal/char in this high-throughput reactor. The tests employed in-bed calcium-based sorbent for sulfur capture. The model was based on elemental mass and energy balances and assumed instantaneous devolatilization and combustion and kinetically limited gasification reactions in a continuously stirred tank reactor. The experimental results on the reaction of these three coals were compared with model predictions. The simulated results compared favorably with the experimental results (e.g., gas composition, carbon conversion, and reactor temperature). The bituminous coal data were accurately simulated as substoichiometric combustion processes. The more reactive subbituminous coal exhibited significant gasification conversion over the operating conditions tested. The subbituminous coal was found to react 20 times faster than reported from laboratory kinetic studies. The model was used to predict the performance of the gasifier, including the carbon conversion, sulfur capture, and composition and flow rate of product gas, based on operating conditions and input streams. Sensitivity studies on the coal feed rate, steam/coal ratio,heat loss, pressure, gas velocity, and coal reactivity were conducted. These simulations were used to compare the response of coals gasified to those combusted substoichiometrically, to evaluate the optimum operating conditions and to predict the performance in larger-scale units with less heat loss. C1 US Dept Energy, Natl Energy Technol Lab, Morgantown, WV 26507 USA. REM Engn Serv, Morgantown, WV 26505 USA. Univ N Dakota, Energy & Environm Res Ctr, Grand Forks, ND 58202 USA. RP Shadle, LJ (reprint author), US Dept Energy, Natl Energy Technol Lab, POB 880, Morgantown, WV 26507 USA. OI Shadle, Lawrence/0000-0002-6283-3628 NR 29 TC 18 Z9 22 U1 1 U2 7 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0888-5885 J9 IND ENG CHEM RES JI Ind. Eng. Chem. Res. PD JUN 27 PY 2001 VL 40 IS 13 BP 2782 EP 2792 DI 10.1021/ie001113u PG 11 WC Engineering, Chemical SC Engineering GA 445CD UT WOS:000169439800003 ER PT J AU Lahti, DW Espenson, JH AF Lahti, DW Espenson, JH TI Issues of microscopic reversibility and an isomeric intermediate in ligand substitution reactions of five-coordinate oxorhenium(V) dithiolate complexes SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID HYDROGEN-PEROXIDE; METHYLRHENIUM TRIOXIDE; BERRY PSEUDOROTATION; TURNSTILE ROTATION; MECHANISM; OXIDATION; OXIDES; KINETICS; RHENIUM; MONOMERIZATION AB Ligand substitution reactions between five-coordinate oxorhenium(V) dithiolates, [CH3ReO(SCH2C6H4S)X], or MeReO(mtp)X, and entering ligands Y have been studied; Y is a phosphine and X is a phosphine (usually) or a pyridine. Many of them occur in two distinct stages, and other two-stage reactions merge to a single kinetic term when the successive rate constants are quite different in value. An intermediate can be detected directly by electronic and NMR spectroscopy. Just for phosphines, the range of rate constants is remarkably large; in the first stage, k spans the range 10(-4)-10(1) L mol(-1) s(-1) at 25 degreesC in benzene; in the second, which also shows a first-order dependence on the concentration of the entering ligand, the range is 10(-4)-10(1) L mol(-1) s(-1). Spectroscopic evidence shows that the intermediate has the same composition as the product; the metastable form is designated as MeReO(mtp)Y*. The structures of all the isolated products MeReO(mtp)Y have a single stereochemistry: Me and -SCH2 lie in trans positions, as do Y and -SAr. This structure is believed to be reversed in the transient, Y and -SCH2 occupying trans positions. Further support for this assignment comes from the P-31 Splitting of the H-1 NMR spectrum, where additional coupling indicates unusual four-bond coupling from a W-pattern of the hydrogen and phosphorus atoms. The intermediate does not undergo an intramolecular rearrangement to the final product; instead, it reacts with a ligand of the same type in an intermolecular reaction leading to rearrangement. The activation parameters were determined for selected reactions, and the results support a mechanism with considerable associative character; DeltaS double dagger values are ca. - 125 J K-1 mol(-1). Because ligand Y must enter the coordination sphere from the vacant coordination position trans to the Re=O group, a means must be devised for the leaving group X to gain that position. To account for the intervention of the isomer while honoring the principle of microscopic reversibility, two mechanisms are proposed. One involves a C-3 ("turnstile") rotation of a specific group of three ligands in the six-coordinate transition state. Turnstile rotation of the groups X, Me, and Y can accomplish the needed transposition; the transition state passes through an approximate trigonal prismatic configuration, giving rise to a different and less stable isomer. The alternative mechanism, which may more easily accommodate data for Y = Me(2)bpy, involves rearrangement of the common octahedral intermediate to a pentagonal pyramid. The arrangement of ligands in the intermediate, governed by their sizes, determines that isomerization accompanies product formation. Following either rearrangement, a second reaction, between MeReO(SCH2C6H4S)Y* and Y, then ensues by the same mechanism. The second rearrangement process then generates the more stable isomer of the product. Results are also presented from a study of monomerization of the dimeric rhenium species, (MeReO(mtp))(2), with phosphines(X) of various size and basicity. The results support a mechanism with two intermediates on the pathway to MeReO(mtp)X. C1 Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Dept Chem, Ames, IA 50011 USA. RP Espenson, JH (reprint author), Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. NR 42 TC 28 Z9 28 U1 0 U2 2 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 JUN 27 PY 2001 VL 123 IS 25 BP 6014 EP 6024 DI 10.1021/ja004145h PG 11 WC Chemistry, Multidisciplinary SC Chemistry GA 446VC UT WOS:000169534000019 PM 11414835 ER PT J AU Jung, EN Peskin, CS AF Jung, EN Peskin, CS TI Two-dimensional simulations of valveless pumping using the immersed boundary method SO SIAM JOURNAL ON SCIENTIFIC COMPUTING LA English DT Article DE valveless pumping; immersed boundary method; frequency; CPR ID BLOOD-FLOW; CARDIOPULMONARY-RESUSCITATION; MATHEMATICAL-MODEL; NUMERICAL-METHOD; MITRAL-VALVE; HEART; MECHANISMS; PARTICLES; MOTION; FLUID AB Flow driven by pumping without valves is examined, motivated by biomedical applications: cardiopulmonary resuscitation ( CPR) and the human fetus before the development of the heart valves. The direction of ow inside a loop of tubing which consists of ( almost) rigid and flexible parts is investigated when the boundary of one end of the flexible segment is forced periodically in time. Despite the absence of valves, net flow around the loop may appear in these simulations. The magnitude and even the direction of this flow depend on the driving frequency of the periodic forcing. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. NYU, Courant Inst Math Sci, New York, NY 10012 USA. RP Jung, EN (reprint author), Oak Ridge Natl Lab, POB 2008,Bldg 6012,MS-6367, Oak Ridge, TN 37831 USA. NR 27 TC 62 Z9 63 U1 1 U2 11 PU SIAM PUBLICATIONS PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 USA SN 1064-8275 J9 SIAM J SCI COMPUT JI SIAM J. Sci. Comput. PD JUN 27 PY 2001 VL 23 IS 1 BP 19 EP 45 DI 10.1137/S1064827500366094 PG 27 WC Mathematics, Applied SC Mathematics GA 451NG UT WOS:000169807700002 ER PT J AU Jones, JE Vassilevski, PS AF Jones, JE Vassilevski, PS TI AMGe based on element agglomeration SO SIAM JOURNAL ON SCIENTIFIC COMPUTING LA English DT Article DE algebraic multigrid; element agglomeration; algebraic coarsening; implementation ID ELLIPTIC PROBLEMS AB This paper contains the main ideas for an AMGe ( algebraic multigrid for finite elements) method based on element agglomeration. In the method, coarse grid elements are formed by agglomerating ne grid elements. Compatible interpolation operators are constructed which yield coarse grid basis functions with a minimal energy property. Heuristics based on interpolation quality measures are used to guide the agglomeration procedure. The performance of the resulting method is demonstrated in two-level numerical experiments. C1 Univ Calif Lawrence Livermore Natl Lab, Ctr Appl Sci Comp, Livermore, CA 94550 USA. RP Jones, JE (reprint author), Univ Calif Lawrence Livermore Natl Lab, Ctr Appl Sci Comp, Mail Stop L-560,7000 East Ave, Livermore, CA 94550 USA. OI Jones, Jim/0000-0002-0144-6130 NR 17 TC 76 Z9 81 U1 0 U2 2 PU SIAM PUBLICATIONS PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 USA SN 1064-8275 J9 SIAM J SCI COMPUT JI SIAM J. Sci. Comput. PD JUN 27 PY 2001 VL 23 IS 1 BP 109 EP 133 DI 10.1137/S1064827599361047 PG 25 WC Mathematics, Applied SC Mathematics GA 451NG UT WOS:000169807700007 ER PT J AU Hough, PD Kolda, TG Torczon, VJ AF Hough, PD Kolda, TG Torczon, VJ TI Asynchronous parallel pattern search for nonlinear optimization SO SIAM JOURNAL ON SCIENTIFIC COMPUTING LA English DT Article DE asynchronous parallel optimization; pattern search; direct search; fault tolerance; distributed computing; cluster computing ID CONSTRAINED MINIMIZATION; NEWTON METHOD; CONVERGENCE; ALGORITHMS AB We introduce a new asynchronous parallel pattern search ( APPS). Parallel pattern search can be quite useful for engineering optimization problems characterized by a small number of variables ( say fifty or less) and by objective functions that are expensive to evaluate, such as those defined by complex simulations that can take anywhere from a few seconds to many hours to run. The target platforms for APPS are the loosely coupled parallel systems now widely available. We exploit the algorithmic characteristics of pattern search to design variants that dynamically initiate actions solely in response to messages, rather than routinely cycling through a fixed set of steps. This gives a versatile concurrent strategy that allows us to effectively balance the computational load across all available processors. Further, it allows us to incorporate a high degree of fault tolerance with almost no additional overhead. We demonstrate the effectiveness of a preliminary implementation of APPS on both standard test problems as well as some engineering optimization problems. C1 Sandia Natl Labs, Computat Sci & Math Res Dept, Livermore, CA 94551 USA. Coll William & Mary, Dept Comp Sci, Williamsburg, VA 23187 USA. RP Hough, PD (reprint author), Sandia Natl Labs, Computat Sci & Math Res Dept, Livermore, CA 94551 USA. RI Kolda, Tamara/B-1628-2009 OI Kolda, Tamara/0000-0003-4176-2493 NR 27 TC 78 Z9 80 U1 0 U2 4 PU SIAM PUBLICATIONS PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 USA SN 1064-8275 J9 SIAM J SCI COMPUT JI SIAM J. Sci. Comput. PD JUN 27 PY 2001 VL 23 IS 1 BP 134 EP 156 DI 10.1137/S1064827599365823 PG 23 WC Mathematics, Applied SC Mathematics GA 451NG UT WOS:000169807700008 ER PT J AU Knupp, PM AF Knupp, PM TI Algebraic mesh quality metrics SO SIAM JOURNAL ON SCIENTIFIC COMPUTING LA English DT Article DE unstructured mesh generation; mesh quality metrics; condition number; shape measures ID JACOBIAN MATRIX NORM; FRAMEWORK; OPTIMIZATION; QUANTITIES; SHAPE AB Quality metrics for structured and unstructured mesh generation are placed within an algebraic framework to form a mathematical theory of mesh quality metrics. The theory, based on the Jacobian and related matrices, provides a means of constructing, classifying, and evaluating mesh quality metrics. The Jacobian matrix is factored into geometrically meaningful parts. A nodally invariant Jacobian matrix can be defined for simplicial elements using a weight matrix derived from the Jacobian matrix of an ideal reference element. Scale and orientation-invariant algebraic mesh quality metrics are defined. The singular value decomposition is used to study relationships between metrics. Equivalence of the element condition number and mean ratio metrics is proved. The condition number is shown to measure the distance of an element to the set of degenerate elements. Algebraic measures for skew, length ratio, shape, volume, and orientation are defined abstractly, with specific examples given. Two combined metrics, shape-volume and shape-volume orientation, are algebraically defined and examples of such metrics are given. Algebraic mesh quality metrics are extended to nonsimplicial elements. A series of numerical tests veri es the theoretical properties of the metrics defined. C1 Sandia Natl Labs, Parallel Comp Sci Dept, Albuquerque, NM 87185 USA. RP Knupp, PM (reprint author), Sandia Natl Labs, Parallel Comp Sci Dept, M-S 0847,POB 5800, Albuquerque, NM 87185 USA. NR 24 TC 118 Z9 120 U1 0 U2 9 PU SIAM PUBLICATIONS PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 USA SN 1064-8275 J9 SIAM J SCI COMPUT JI SIAM J. Sci. Comput. PD JUN 27 PY 2001 VL 23 IS 1 BP 193 EP 218 DI 10.1137/S1064827500371499 PG 26 WC Mathematics, Applied SC Mathematics GA 451NG UT WOS:000169807700011 ER PT J AU Kenseth, JR Harnisch, JA Jones, VW Porter, MD AF Kenseth, JR Harnisch, JA Jones, VW Porter, MD TI Investigation of approaches for the fabrication of protein patterns by scanning probe lithography SO LANGMUIR LA English DT Article ID SELF-ASSEMBLED MONOLAYERS; ATOMIC-FORCE MICROSCOPY; LINKED-IMMUNOSORBENT-ASSAY; DNA DSDNA MICROARRAYS; GOLD SURFACES; MICROFLUIDIC NETWORKS; COVALENT IMMOBILIZATION; SMALL MOLECULES; ANTIBODIES; ADSORPTION AB This paper investigates three different approaches to patterning proteins within ultrathin resist layers formed from self-assembled monolayers using scanning probe lithography (SPL) at the submicrometer length scale. The first approach uses a "nanografting" method to pattern a reactive carboxylic acid terminated thiol into a resist composed of a methyl-terminated monolayer. Rabbit IgG antigen is bound to the patterned region, and an immunoassay utilizing direct readout of the topographic change resulting from specific binding of anti-rabbit IgG antibody is performed using scanning force microscopy. To address issues related to nonspecific protein adsorption, the other two approaches investigated the patterned removal of glycol-terminated monolayers by mechanically "scraping" patterns at high tip-sample forces by SPL. Protein attachment to the scraped regions was achieved either through the chemisorption of a disulfide coupling agent or by the direct adsorption of Fab'-SH antibody fragments. Results obtained from all approaches are presented and compared, and the strengths and weaknesses of each toward fabricating high-density, multiple protein arrays are discussed. C1 Iowa State Univ Sci & Technol, Ames Lab, Microanalyt Instrumentat Ctr, USDOE, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Dept Chem, Ames, IA 50011 USA. RP Porter, MD (reprint author), Iowa State Univ Sci & Technol, Ames Lab, Microanalyt Instrumentat Ctr, USDOE, Ames, IA 50011 USA. NR 54 TC 86 Z9 88 U1 2 U2 23 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0743-7463 J9 LANGMUIR JI Langmuir PD JUN 26 PY 2001 VL 17 IS 13 BP 4105 EP 4112 DI 10.1021/la0100744 PG 8 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 445LY UT WOS:000169460000048 ER PT J AU Chow, WW Schneider, HC AF Chow, WW Schneider, HC TI Charge-separation effects in 1.3 mu m GaAsSb type-II quantum-well laser gain SO APPLIED PHYSICS LETTERS LA English DT Article AB A microscopic laser theory is used to investigate gain and threshold properties in a GaAsSb quantum-well laser. Depending on the geometry of the type-II quantum-well gain region, there may be appreciable band distortions due to electron-hole charge separation. The charge separation and accompanying band distortions lead to interesting optical behaviors, such as excitation-dependent oscillator strength and band edge energies. Implications to laser operation include significant blueshift of the gain peak with increasing injection current, and inhibition of spontaneous emission, which may result in threshold current reduction. (C) 2001 American Institute of Physics. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Chow, WW (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. RI Schneider, Hans Christian/B-9450-2009 OI Schneider, Hans Christian/0000-0001-7656-4919 NR 12 TC 20 Z9 20 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD JUN 25 PY 2001 VL 78 IS 26 BP 4100 EP 4102 DI 10.1063/1.1379784 PG 3 WC Physics, Applied SC Physics GA 443KH UT WOS:000169340000013 ER PT J AU Hakim, N Parimi, PV Kusko, C Sridhar, S Canfield, PC Bud'ko, SL Finnemore, DK AF Hakim, N Parimi, PV Kusko, C Sridhar, S Canfield, PC Bud'ko, SL Finnemore, DK TI Microwave properties of superconducting MgB2 SO APPLIED PHYSICS LETTERS LA English DT Article ID FILMS AB Measurements of 10 GHz microwave surface resistance, R-s, of dense MgB2 wire and pellet are reported. Significant improvements are observed in the wire with reduction of porosity. The data lie substantially above the theoretical estimates for a pure Bardeen-Cooper-Schrieffer s-wave superconductor. However, the R-s (20 K) of the wire is an order of magnitude lower than that of polycrystal YBa2Cu3O6.95 and matches with single-crystal YBa2Cu3O6.95. The results show promise for the use of MgB2 in microwave applications. (C) 2001 American Institute of Physics. C1 Northeastern Univ, Dept Phys, Boston, MA 02115 USA. Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. RP Hakim, N (reprint author), Northeastern Univ, Dept Phys, 360 Huntington Ave, Boston, MA 02115 USA. RI Sridhar, Srinivas/A-3688-2012; Kusko, Cristian/C-5336-2012; Canfield, Paul/H-2698-2014 NR 11 TC 15 Z9 15 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD JUN 25 PY 2001 VL 78 IS 26 BP 4160 EP 4162 DI 10.1063/1.1379366 PG 3 WC Physics, Applied SC Physics GA 443KH UT WOS:000169340000033 ER PT J AU Doyuran, A Babzien, M Shaftan, T Yu, LH DiMauro, LF Ben-Zvi, I Biedron, SG Graves, W Johnson, E Krinsky, S Malone, R Pogorelsky, I Skaritka, J Rakowsky, G Wang, XJ Woodle, M Yakimenko, V Jagger, J Sajaev, V Vasserman, I AF Doyuran, A Babzien, M Shaftan, T Yu, LH DiMauro, LF Ben-Zvi, I Biedron, SG Graves, W Johnson, E Krinsky, S Malone, R Pogorelsky, I Skaritka, J Rakowsky, G Wang, XJ Woodle, M Yakimenko, V Jagger, J Sajaev, V Vasserman, I TI Characterization of a high-gain harmonic-generation free-electron laser at saturation SO PHYSICAL REVIEW LETTERS LA English DT Article ID AMPLIFIED SPONTANEOUS-EMISSION; 3-DIMENSIONAL ANALYSIS; FEL; NM AB We report on an experimental investigation characterizing the output of a high-gain harmonic-generation (HGHG) free-electron laser (FEL) at saturation. A seed CO2 laser at a wavelength of 10.6 mum was used to generate amplified FEL output at 5.3 mum. Measurement of the frequency spectrum, pulse duration, and correlation length of the 5.3 mum output verified that the light is longitudinally coherent. Investigation of the electron energy distribution and output harmonic energies provides evidence for saturated HGHG FEL operation. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. RP Doyuran, A (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. RI Shaftan, Timur/A-8443-2009 NR 31 TC 45 Z9 47 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 JUN 25 PY 2001 VL 86 IS 26 BP 5902 EP 5905 DI 10.1103/PhysRevLett.86.5902 PG 4 WC Physics, Multidisciplinary SC Physics GA 445XQ UT WOS:000169484200015 PM 11415390 ER PT J AU Iota, V Yoo, CS AF Iota, V Yoo, CS TI Phase diagram of carbon dioxide: Evidence for a new associated phase SO PHYSICAL REVIEW LETTERS LA English DT Article ID HIGH-PRESSURE PHASE; SOLID CO2; CRYSTAL-STRUCTURE; DENSE HYDROGEN; TEMPERATURE; RAMAN; GPA AB The stability of CO2 phases has been investigated up to 50 GPa and 750 K by in situ Raman spectroscopy and visual observations using externally heated diamond-anvil cells. A new phase (CO2-II) exists above 20 GPa and 500 K, which can be quenched to ambient temperature. The vibrational spectrum of this new CO2 polymorph suggests the dimeric pairing of molecules. Based on the present in situ data and previous laser-heating results, we present new constraints for the phase diagram of carbon dioxide to 50 GPa and 2000 K. We find that carbon dioxide exhibits dramatic changes, both in the molecular configuration and in the nature of intermolecular interaction at high pressures and temperatures. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Iota, V (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 30 TC 33 Z9 35 U1 1 U2 23 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 JUN 25 PY 2001 VL 86 IS 26 BP 5922 EP 5925 DI 10.1103/PhysRevLett.86.5922 PG 4 WC Physics, Multidisciplinary SC Physics GA 445XQ UT WOS:000169484200020 PM 11415394 ER PT J AU Li, M Tikhonov, AM Chaiko, DJ Schlossman, ML AF Li, M Tikhonov, AM Chaiko, DJ Schlossman, ML TI Coupled capillary wave fluctuations in thin aqueous films on an aqueous subphase SO PHYSICAL REVIEW LETTERS LA English DT Article ID X-RAY-SCATTERING; SURFACE SCATTERING; NEUTRON-SCATTERING; LIQUID-FILMS; ROUGH; MULTILAYERS; REFLECTION; INTERFACE; SYSTEMS AB X-ray scattering and interfacial tension measurements are used to demonstrate the formation of nanometer-thick aqueous films on aqueous bulk subphases from polymer-salt biphase mixtures. X-ray scattering determines a coupling constant that characterizes the coupled capillary wave fluctuations of the liquid-vapor and liquid-liquid interfaces of this thin film. These data also determine an effective Hamakar constant that characterizes the long-range interaction between the interfaces and parameters that characterize the short-range part of the interfacial interaction. C1 Univ Illinois, Dept Phys, Chicago, IL 60607 USA. Argonne Natl Lab, Div Chem Technol, Argonne, IL 60439 USA. Univ Illinois, Dept Chem, Chicago, IL 60607 USA. RP Li, M (reprint author), Univ Illinois, Dept Phys, 845 W Taylor St, Chicago, IL 60607 USA. RI Tikhonov, Aleksey/N-1111-2016 NR 29 TC 16 Z9 17 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 JUN 25 PY 2001 VL 86 IS 26 BP 5934 EP 5937 DI 10.1103/PhysRevLett.86.5934 PG 4 WC Physics, Multidisciplinary SC Physics GA 445XQ UT WOS:000169484200023 PM 11415397 ER PT J AU Wang, SW Di Ventra, M Kim, SG Pantelides, ST AF Wang, SW Di Ventra, M Kim, SG Pantelides, ST TI Atomic-scale dynamics of the formation and dissolution of carbon clusters in SiO2 SO PHYSICAL REVIEW LETTERS LA English DT Article ID SIC/SIO2 INTERFACE STATES; RANDOM-NETWORK MODEL; THIN-FILM OXIDATION; SILICON-CARBIDE; PRECIPITATION; ELECTRON; 4H AB Oxidation of SiC produces SiO2 while CO is released. A "reoxidation" step at lower temperatures is, however, necessary to produce high-quality SiO2. This step is believed to cleanse the oxide of residual C without further oxidation of the SiC substrate. We report first-principles calculations that describe the nucleation and growth of O-deficient C clusters in SiO2 under oxidation conditions, fed by the production of CO at the advancing interface, and their gradual dissolution by the supply of O under reoxidation conditions. We predict that both CO and CO2 are released during both steps. C1 Vanderbilt Univ, Dept Phys & Astron, Nashville, TN 37235 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Wang, SW (reprint author), Florida State Univ, Sch Computat Sci & Informat Technol, Tallahassee, FL 32306 USA. RI Di Ventra, Massimiliano/E-1667-2011 OI Di Ventra, Massimiliano/0000-0001-9416-189X NR 18 TC 68 Z9 68 U1 0 U2 7 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD JUN 25 PY 2001 VL 86 IS 26 BP 5946 EP 5949 DI 10.1103/PhysRevLett.86.5946 PG 4 WC Physics, Multidisciplinary SC Physics GA 445XQ UT WOS:000169484200026 PM 11415400 ER PT J AU Surh, MP Barbee, TW Yang, LH AF Surh, MP Barbee, TW Yang, LH TI First principles molecular dynamics of dense plasmas SO PHYSICAL REVIEW LETTERS LA English DT Article ID CORE-LEVEL SHIFTS; SHOCK COMPRESSIBILITY; ULTRAHIGH PRESSURE; STATE; EQUATION; ALUMINUM; AL; LIQUIDS; SURFACE; ENERGY AB Ab initio molecular dynamics calculations are performed for the equation of state of aluminum, spanning condensed matter and dense plasma regimes. Electronic exchange and correlation are included with either a zero- or finite-temperature local density approximation potential. Standard methods are extended to. above the Fermi temperature by using final state pseudopotentials to describe thermally excited ion. cores. The predicted Hugoniot equation of state agrees well with earlier plasma theories and with experiment for temperatures from 0 to 3 X 10(6) K. C1 Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Surh, MP (reprint author), Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 36 TC 32 Z9 32 U1 0 U2 6 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 JUN 25 PY 2001 VL 86 IS 26 BP 5958 EP 5961 DI 10.1103/PhysRevLett.86.5958 PG 4 WC Physics, Multidisciplinary SC Physics GA 445XQ UT WOS:000169484200029 PM 11415403 ER PT J AU Morr, DK Trautman, PF Graf, MJ AF Morr, DK Trautman, PF Graf, MJ TI Resonance peak in Sr2RuO4: Signature of spin triplet pairing SO PHYSICAL REVIEW LETTERS LA English DT Article ID PEROVSKITE SUPERCONDUCTOR SR2RUO4; NEUTRON-SCATTERING; LAYERED PEROVSKITE; ORDER-PARAMETER; FERMI-SURFACE; FLUCTUATIONS; YBA2CU3O7; SYMMETRY; STATES AB We study the dynamical spin susceptibility, chi (q,omega), in the normal and superconducting states of Sr2RuO4. In the normal state, we find a peak in the vicinity of Q(i) similar or equal to (0.72 pi, 0.72 pi) in agreement with recent inelastic neutron scattering experiments. We predict that for spin triplet pairing in the superconducting state a resonance peak appears in the out-of-plane component of chi, but is absent in the in-plane component. In contrast, no resonance peak is expected for spin singlet pairing. C1 Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Baylor Univ, Waco, TX 76798 USA. RP Morr, DK (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, MS B262, Los Alamos, NM 87545 USA. OI Morr, Dirk/0000-0003-3692-2835 NR 33 TC 30 Z9 30 U1 1 U2 3 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD JUN 25 PY 2001 VL 86 IS 26 BP 5978 EP 5981 DI 10.1103/PhysRevLett.86.5978 PG 4 WC Physics, Multidisciplinary SC Physics GA 445XQ UT WOS:000169484200034 PM 11415408 ER PT J AU Molvik, AW AF Molvik, AW TI Comment on "Upper limit to Landau damping in helicon discharges" SO PHYSICAL REVIEW LETTERS LA English DT Article C1 Univ Calif Lawrence Livermore Natl Lab, Fus Energy Program, Livermore, CA 94551 USA. RP Molvik, AW (reprint author), Univ Calif Lawrence Livermore Natl Lab, Fus Energy Program, L-645,POB 808, Livermore, CA 94551 USA. NR 3 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 JUN 25 PY 2001 VL 86 IS 26 BP 6048 EP 6048 DI 10.1103/PhysRevLett.86.6048 PG 1 WC Physics, Multidisciplinary SC Physics GA 445XQ UT WOS:000169484200053 PM 11415427 ER PT J AU Davidson, RC Uhm, HS AF Davidson, RC Uhm, HS TI Effects of a solenoidal focusing field on the electron-ion two-stream instability in high-intensity ion beams SO PHYSICS LETTERS A LA English DT Article ID PSR AB A rigid-beam model is used to investigate the influence of a solenoidal focusing field B-0(e) over cap (Z) on the electron-ion two-stream instability that can occur in high-intensity ion beams when an (unwanted) component of background electrons is present. A relatively weak solenoidal magnetic field strongly constrains the transverse electron motion and can lead to a significant reduction in instability growth rate whenever omega (2)(pe) much greater than 2(n(b)e(b)/n(e)e)omega (2)(pe). Here, omega (ce) = eB(0)/m(e)c is the electron gyrofrequency, omega (pe) = (4 pin(e)e(2)/m(e))(1/2) is the electron plasma frequency, and n(b) and n(e) are the ion and electron number densities. (C) 2001 Elsevier Science B.V. All. rights reserved. C1 Princeton Univ, Plasma Phys Lab, Princeton, NJ 08543 USA. Ajou Univ, Dept Mol Sci & Technol, Suwon 442749, South Korea. RP Davidson, RC (reprint author), Princeton Univ, Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 18 TC 11 Z9 11 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9601 J9 PHYS LETT A JI Phys. Lett. A PD JUN 25 PY 2001 VL 285 IS 1-2 BP 88 EP 93 DI 10.1016/S0375-9601(01)00245-6 PG 6 WC Physics, Multidisciplinary SC Physics GA 449TQ UT WOS:000169703600015 ER PT J AU Flinn, JE Field, DP Korth, GE Lillo, TM Macheret, J AF Flinn, JE Field, DP Korth, GE Lillo, TM Macheret, J TI The flow stress behavior of OFHC polycrystalline copper SO ACTA MATERIALIA LA English DT Article DE copper; grain boundaries; stress-strain relationship measurements; dislocations; transmission electron microscopy (TEM) ID STACKING-FAULT ENERGY; GRAIN-SIZE; SINGLE-CRYSTALS; FCC METALS; ALLOYS; EVOLUTION; BOUNDARY; TWINS; MODEL AB The flow stress behavior of OFHC polycrystalline copper was evaluated using cold-rolled and equal channel angular extruded materials. Prior to tensile testing at room temperature, the specimens were heat treated to obtain grain sizes ranging from 3 to 60 mum. The how stress, when correlated with the square root of true strain, is associated with four stages of hardening. These stages, in terms of increasing strain, are attributed to: (1) dislocation source activation, possibly at annealing twin boundaries during the onset of plastic flow, (2) dislocation slip and cross slip, (3) constriction of the screw dislocation partials for cross slip continuation, and (4) dislocation annihilation and saturation as interpreted through dynamic recovery. The tensile properties and analyses are supported by observations and measurements from orientation imaging and transmission electron microscopy. (C) 2001 Acta Materialia Inc. Published by Elsevier Science Ltd. All rights reserved. C1 Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. Univ Idaho, Idaho Falls, ID 83402 USA. Washington State Univ, Dept Mech & Mat Engn, Pullman, WA 99164 USA. US DOE, Idaho Falls, ID 83401 USA. RP Lillo, TM (reprint author), Idaho Natl Engn & Environm Lab, POB 1625, Idaho Falls, ID 83415 USA. RI Field, David/D-5216-2012; Lilllo, Thomas/S-5031-2016 OI Field, David/0000-0001-9415-0795; Lilllo, Thomas/0000-0002-7572-7883 NR 44 TC 41 Z9 43 U1 2 U2 14 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 JUN 22 PY 2001 VL 49 IS 11 BP 2065 EP 2074 DI 10.1016/S1359-6454(01)00102-1 PG 10 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 442YL UT WOS:000169312500020 ER PT J AU Rak, J Skurski, P Gutowski, M AF Rak, J Skurski, P Gutowski, M TI An ab initio study of the betaine anion-dipole-bound anionic state of a model zwitterion system SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID DENSITY-FUNCTIONAL THEORY; FRANCK-CONDON PRINCIPLE; GAS-PHASE; PHOTOELECTRON-SPECTROSCOPY; SEMIEMPIRICAL METHODS; VIBRONIC TRANSITIONS; POLYATOMIC-MOLECULES; ELECTRONIC-STRUCTURE; GLYCINE ZWITTERION; DYNAMICAL SYMMETRY AB The electron binding to a model zwitterionic molecule, betaine, is studied at the coupled cluster level of theory with single, double, and noniterative triple excitations as well as at the density functional theory level. Our results indicate that there is only one stable conformer of betaine with a dipole moment of 11.5 D. This dipole moment supports a relatively strongly bound anionic state and the vertical electron detachment energy was found to be 2261 cm(-1). Furthermore, we predict the excess electron binding energy for the betaine analog with a blocked canonical structure (N,N-dimethylglycine methyl ester) to be less than 100 cm(-1). This significant difference in electron binding energies suggests that the gas phase instability of zwitterions of some common naturally occurring amino acids with respect to their canonical forms may be reversed by the excess electron attachment. The calculated Franck-Condon factors for the betaine's anion/neutral pair suggest that the photoelectron spectrum of the anion will display only a very weak vibrational structure. (C) 2001 American Institute of Physics. C1 Univ Gdansk, Dept Chem, PL-80952 Gdansk, Poland. Univ Utah, Dept Chem, Henry Eyring Ctr Theoret Chem, Salt Lake City, UT 84112 USA. Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Rak, J (reprint author), Univ Gdansk, Dept Chem, Ul Sobieskiego 18, PL-80952 Gdansk, Poland. EM janusz@raptor.chem.univ.gda.pl; maciej.gutowski@pnl.gov NR 64 TC 46 Z9 46 U1 1 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 0021-9606 EI 1089-7690 J9 J CHEM PHYS JI J. Chem. Phys. PD JUN 22 PY 2001 VL 114 IS 24 BP 10673 EP 10681 DI 10.1063/1.1373689 PG 9 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 441HL UT WOS:000169224900014 ER PT J AU Liu, DJ Evans, JW AF Liu, DJ Evans, JW TI Phase transitions in mixed adsorbed layers: Effect of repulsion between "hard squares" and "point particles" SO JOURNAL OF CHEMICAL PHYSICS LA English DT Letter ID CORE LATTICE MODEL; GAS MODEL; OXIDATION C1 Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Math, Ames, IA 50011 USA. RP Iowa State Univ, Ames Lab, Ames, IA 50011 USA. NR 19 TC 2 Z9 2 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 0021-9606 EI 1089-7690 J9 J CHEM PHYS JI J. Chem. Phys. PD JUN 22 PY 2001 VL 114 IS 24 BP 10977 EP 10978 DI 10.1063/1.1374209 PG 2 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 441HL UT WOS:000169224900050 ER PT J AU Breadmore, MC Haddad, PR Fritz, JS AF Breadmore, MC Haddad, PR Fritz, JS TI Optimisation of the separation of anions by ion chromatography-capillary electrophoresis using indirect UV detection SO JOURNAL OF CHROMATOGRAPHY A LA English DT Article; Proceedings Paper CT 13th International Ion Chromatography Symposium (IICS 2000) CY SEP 11-14, 2000 CL NICE, FRANCE DE ion chromatography-capillary electrophoresis; optimization; indirect detection; mathematical modelling; background electrolyte composition; electrochromatography; electrokinetic chromatography; inorganic anions; organic acids; poly(diallyldimethalammonium chloride) ID EXCHANGE ELECTROKINETIC CHROMATOGRAPHY; CATIONIC POLYMERS; INORGANIC ANIONS; ELECTROCHROMATOGRAPHY; SELECTIVITY AB The separation of a complex mixture of inorganic and organic anions by ion chromatography-capillary electrophoresis using a cationic polymer added to the background electrolyte and indirect UV detection has been studied. The addition of unmodified polymer to an electrolyte suitable for indirect detection resulted in the appearance of a system peak due to the counter-anion on the polymer and while the position of the analytes relative to this system peak could be changed, this was found to be an unacceptable approach for mixtures of large numbers of analytes. Although conversion of the polymer to replace the counter-ion with the indirect W detection probe ion simplified the system, this approach restricted the flexibility of the system because the probe and polymer concentration were necessarily linked. This limitation could be overcome by selecting the appropriate type of probe ion, with probes having a low ion-exchange selectivity coefficient providing greater retention of analytes than probes with a high ion-exchange selectivity coefficient. Three electrolyte systems with different probes (benzoate, chromate and phthalate) were modelled using a previously derived migration equation and this was used to optimise the electrolyte composition to enable the separation of a mixture of 24 inorganic and organic anions within 7 min. The electrolyte composition was then optimised for the analysis of anions in Bayer liquor with the-final separation selectivity being substantially improved for selected key analytes. (C) 2001 Elsevier Science BN. All rights reserved. C1 Univ Tasmania, Hobart, Tas 7001, Australia. Iowa State Univ Sci & Technol, Dept Chem, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. RP Haddad, PR (reprint author), Univ Tasmania, GPO 252-75, Hobart, Tas 7001, Australia. NR 13 TC 26 Z9 26 U1 1 U2 8 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0021-9673 J9 J CHROMATOGR A JI J. Chromatogr. A PD JUN 22 PY 2001 VL 920 IS 1-2 BP 31 EP 40 DI 10.1016/S0021-9673(00)01263-2 PG 10 WC Biochemical Research Methods; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA 447PD UT WOS:000169580900005 PM 11453016 ER PT J AU Hu, W Haddad, PR Cook, H Yamamoto, H Hasebe, K Tanaka, K Fritz, JS AF Hu, W Haddad, PR Cook, H Yamamoto, H Hasebe, K Tanaka, K Fritz, JS TI Manipulation of separation selectivity of inorganic anions in electrostatic ion chromatography by the use of mixed cationic-zwitterionic micelles as the column coating solution SO JOURNAL OF CHROMATOGRAPHY A LA English DT Article; Proceedings Paper CT 13th International Ion Chromatography Symposium (IICS 2000) CY SEP 11-14, 2000 CL NICE, FRANCE DE micelles; electrostatic ion chromatography; ion chromatography; stationary phases, LC; selectivity; coated columns; inorganic anions ID STATIONARY-PHASE; ELUENTS AB This paper describes an electrostatic ion chromatographic system in which the separation selectivity for inorganic anions, especially for sulfate and phosphate, could be manipulated by altering the molar ratio of the zwitterionic and cationic surfactants in the column coating solution used to prepare the stationary phase. The zwitterionic surfactant used for this study was 3-(N,N-dimethyltetradecylammonio)propane (Zwittergent-3-14) and the cationic surfactant was tetradecyl-trimethylammonium (TTA). Using a reversed-phase C-18 column (250 x 4.6 mm I.D.) coated with 10/10 (mM/mM) of TTA/Zwittergent-3-14 mixed micelles as the stationary phase and either NaHCO3 or Na2CO3 aqueous solution as the eluent, together with suppressed conductivity detection, baseline separation of seven model inorganic anions was obtained. The elution order for those anions was found to be F-< HPO42- < Cl- < SO42- < NO2- < Br- < NO3-. Under the same conditions but using 1/10 (mM/mM) of TTA/Zwittergent-3-14 mixed micelles as the column coating solution, the elution order for these model ions was F- < HPO42- < SO42- < Cl- < NO2- < Br- < NO3-. The early elution of phosphate and sulfate is a unique attribute of this system. Detection limits for F-, HPO42-, Cl-, SO42-, NO2-, Br- and NO3- (S/N=3, sample injection volume 100 mul) were 0.11, 0.12, 0.12, 0.18, 0.49, 0.49, 0.52 muM, respectively. (C) 2001 Elsevier Science B;V. All rights reserved. C1 Hokkaido Univ, Grad Sch Sci, Div Chem, Sapporo, Hokkaido 0600810, Japan. Univ Tasmania, Sch Chem, Hobart, Tas 7001, Australia. Hokkaido Univ, Grad Sch Environm Earth Sci, Div Sci Mat, Sapporo, Hokkaido 0600810, Japan. Natl Ind Res Inst Nagoya, Nagoya, Aichi 4628510, Japan. Iowa State Univ, Ames Lab, USDOE, Ames, IA USA. Iowa State Univ, Dept Chem, Ames, IA USA. RP Hu, W (reprint author), Hokkaido Univ, Grad Sch Sci, Div Chem, Sapporo, Hokkaido 0600810, Japan. NR 9 TC 11 Z9 11 U1 1 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0021-9673 J9 J CHROMATOGR A JI J. Chromatogr. A PD JUN 22 PY 2001 VL 920 IS 1-2 BP 95 EP 100 DI 10.1016/S0021-9673(01)00534-9 PG 6 WC Biochemical Research Methods; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA 447PD UT WOS:000169580900012 PM 11453029 ER PT J AU Stohr, J Samant, MG Luning, J Callegari, AC Chaudhari, P Doyle, JP Lacey, JA Lien, SA Purushothaman, S Speidell, JL AF Stohr, J Samant, MG Luning, J Callegari, AC Chaudhari, P Doyle, JP Lacey, JA Lien, SA Purushothaman, S Speidell, JL TI Liquid crystal alignment on carbonaceous surfaces with orientational order SO SCIENCE LA English DT Article ID FILMS; DISPLAYS AB We used near-edge x-ray absorption fine structure (NEXAFS) spectroscopy to Link the orientational bond order at three carbonaceous surfaces-rubbed polyimide, ion beam-irradiated polyimide, and ion beam-irradiated diamond-like carbon films-with the direction of liquid crystal (LC) alignment on these surfaces. We show that, in general, LC alignment can be created on any carbonaceous substrate by inducing orientational order at its surface. Our results form the scientific basis for LC alignment layers consisting of amorphous carbon films in which orientational order near the surface is induced by a directional low-energy ion beam. C1 IBM Corp, Almaden Res Ctr, Div Res, San Jose, CA 95120 USA. IBM Corp, Thomas J Watson Res Ctr, Div Res, Yorktown Heights, NY 10598 USA. RP Stohr, J (reprint author), Stanford Synchrotron Radiat Lab, POB 20450,Mail Stop 69, Stanford, CA 94309 USA. NR 23 TC 235 Z9 238 U1 7 U2 42 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 JUN 22 PY 2001 VL 292 IS 5525 BP 2299 EP 2302 DI 10.1126/science.1059866 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 445KD UT WOS:000169455900048 PM 11423654 ER PT J AU Phillips, DH Foss, JE Stiles, CA Trettin, CC Luxmoore, RJ AF Phillips, DH Foss, JE Stiles, CA Trettin, CC Luxmoore, RJ TI Soil-landscape relationships at the lower reaches of a watershed at Bear Creek near Oak Ridge, Tennessee SO CATENA LA English DT Article DE catena; Nolichucky Shale; redoximorphic features; saprolite; watershed; riparian wetland ID WETLANDS AB The watersheds at Bear Creek, Oak Ridge, TN, have similar soil-landscape relationships. The lower reaches of many of these watersheds consist of headwater riparian wetlands situated between sloping non-wetland upland zones. The objectives of this study are to examine the effects of (i) slops and geomorphic processes, (ii) human impacts, and (iii) particular characteristics of soils and saprolite that may effect drainage and water movement in the wetlands and adjacent landscapes in one of these watersheds. A transect was run from west to east in a hydrological monitored area at the lower reaches of a watershed on Bear Creek. This transect extended from a steep side slope position across a floodplain, a terrace. acid a shoulder slope, On the upland positions of the Nolichucky Shale, mass wasting, overland flow and soil creep currently inhibit soil formation on the steep side slope position where a Typic Dystrudept is present, while soil stability on the shoulder slope has resulted in the formation of a well-developed Typic Hapludult. In these soils, argillic horizons occur above C horizons on less sloping gradients in comparison to steeper slopes, which have Bw horizons over Cr (saprolite) material. A riparian wetland area occupies the floodplain section, where a Typic Endoaquept is characterized by poorly drained conditions that led to the development of redoximorphic features (mottling). gleying, organic matter accumulation, and minimal development of subsurface horizons. A thin colluvial deposit overlies a thick well developed Aquic Hapludalf that formed in alluvial sediments on the terrace position. The colluvial deposit from the adjacent shoulder slope is thought to result from soil creep and anthropogenic erosion caused by past cultivation practices. Runoff from the adjacent sloping landscape and groundwater from the adjacent wetland area perhaps contribute to the somewhat poorly drained conditions of this profile. Perched watertables occur in upland positions due to dense saprolite and clay plugging in the shallow zones of the saprolite. However, no redoximorphic features are observed in the soil on the side slope due to high runoff. Remnants of the underlying shale saprolite. which occur as small discolored zones resembling mottles, are also present. The soils in the study have a CEC of < 10 cmol kg(-1). silt loam textures and Fe-d values of 0.5-4.3%. These soils are also mainly acidic and low in total carbon. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. Univ Tennessee, Dept Plant & Soil Sci, Knoxville, TN 37901 USA. USDA, For Serv, Ctr Forested Wetlands Res, Charlston, SC USA. RP Phillips, DH (reprint author), Oak Ridge Natl Lab, Div Environm Sci, POB 2008,MS 36, Oak Ridge, TN 37831 USA. RI Phillips, Debra/F-1828-2010 OI Phillips, Debra/0000-0001-8548-7409 NR 32 TC 14 Z9 17 U1 2 U2 13 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0341-8162 J9 CATENA JI Catena PD JUN 21 PY 2001 VL 44 IS 3 BP 205 EP 222 DI 10.1016/S0341-8162(00)00156-9 PG 18 WC Geosciences, Multidisciplinary; Soil Science; Water Resources SC Geology; Agriculture; Water Resources GA 434BG UT WOS:000168794800003 ER PT J AU Piermarini, V Balint-Kurti, GG Gray, SK Gogtas, F Lagana, A Hernandez, ML AF Piermarini, V Balint-Kurti, GG Gray, SK Gogtas, F Lagana, A Hernandez, ML TI Wave packet calculation of cross sections, product state distributions, and branching ratios for the O(D-1)+HCl reaction SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID QUANTUM SCATTERING CALCULATIONS; POTENTIAL-ENERGY SURFACE; AB-INITIO; MECHANICAL CALCULATION; RATE CONSTANTS; DYNAMICS; HCL; O(D-1)+H-2->OH+H; HOCL; O(1D2)+HCL->OH+CL AB Time-dependent quantum mechanical calculations have been carried out to estimate the total reactive cross sections, product branching ratios, and product quantum state distributions for the O(D-1) + HCl reaction using both reactant and product Jacobi coordinates. The potential energy surface of T. Martinet et al. (Phys. Chem. Chem. Phys. 2000, 2, 589) has been used in the calculations. The theoretical predictions are compared with experimental results and with the results of classical trajectory calculations on the same surface. The comparisons demonstrate the suitability of the potential energy surface and provide useful insights into the reaction mechanism. The calculations using product Jacobi coordinates are the first calculations for this system which permit the prediction of state-to-state reaction probabilities and of product quantum state distributions. C1 Univ Bristol, Sch Chem, Bristol, Avon, England. Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. Firat Univ, Dept Phys, TR-23119 Elazig, Turkey. Univ Perugia, Dipartimento Chim, I-06123 Perugia, Italy. Univ Salamanca, Dept Fis Atmosfera, E-37008 Salamanca, Spain. RP Lagana, A (reprint author), Univ Bristol, Sch Chem, Bristol, Avon, England. RI Lagana, Antonio/E-8215-2014 OI Lagana, Antonio/0000-0002-3886-7342 NR 45 TC 27 Z9 27 U1 2 U2 7 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 JUN 21 PY 2001 VL 105 IS 24 BP 5743 EP 5750 DI 10.1021/jp004237t PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 443YN UT WOS:000169371300004 ER PT J AU Decker, BK He, G Tokue, I Macdonald, RG AF Decker, BK He, G Tokue, I Macdonald, RG TI Determination of the branching ratios for the reaction of hot H atoms with BrCN and ClCN SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID REACTION DYNAMICS; TRANSITION-MOMENT; INFRARED CHEMILUMINESCENCE; ENERGY-DISTRIBUTION; RATE-CONSTANT; RED SYSTEM; CN; PHOTOLYSIS; HCN; NM AB The relative rates for the reaction of translationally energetic H atoms-with XCN to yield HNC + X, HCN + X, and HX + CN, where X is Br or Cl, have been determined using time- and frequency-resolved absorption spectroscopy. The H atoms were created with an average translational energy of 92 kJ mol(-1) by the laser photolysis of CH3SH at a wavelength of 248 nm. The measurements were carried out at a total pressure of several torr. The dominant channel for each reaction system was the production of hydrogen isocyanide, HNC. The relative branching ratios for H + BrCN and H + ClCN were determined to be 0.85/0.13/0.017 and 0.74/0.25/0.01 for the HNC/HCN/HX + CN channels, respectively. The ratio of the total reaction cross sections, sigma (XCN), was found to be sigma (BrCN)/sigma (ClCN) = 0.84. C1 Niigata Univ, Fac Sci, Dept Chem, Niigata 95021, Japan. RP Macdonald, RG (reprint author), Argonne Natl Lab, Dept Chem, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 46 TC 3 Z9 3 U1 0 U2 2 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 JUN 21 PY 2001 VL 105 IS 24 BP 5759 EP 5767 DI 10.1021/jp004465n PG 9 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 443YN UT WOS:000169371300006 ER PT J AU Maharrey, SP Miller, DR AF Maharrey, SP Miller, DR TI A direct sampling mass spectrometer investigation of oxidation mechanisms for acetic acid in supercritical water SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID RAMAN-SPECTROSCOPY; GAS-CHROMATOGRAPH; TEMPERATURES; INTERFACE; KINETICS; FLUID AB A quartz capillary microreactor:is directly coupled to a mass spectrometer utilizing the exit of the reactor as a standard high-pressure free-jet molecular beam source. This direct sampling mass spectrometry (DSMS) design is used to-probe the reaction mechanism for the oxidation of acetic acid in supercritical water. The DSMS system is able to probe reactor conditions and to detect reaction intermediates, radicals, and product species during the early stages of reaction at the extreme pressures (> 23 MPa) and temperatures (400-500 OC)of interest to supercritical water oxidation; The oxidation of acetic acid with hydrogen peroxide in supercritical water was selected as a prototypical oxidation reaction to validate:our DSMS design. We report on our initial results, which include (1) the complete decomposition of the,hydrogen peroxide to oxygen before 450 degreesC, (2) the subsequent onset of reaction at 470 degreesC, (3) the identification and measurement of the HO2* radical, indicating hydrogen abstraction by oxygen as the dominate initiation step, and (4) the lack of any bulk water incorporation into the reaction mechanism up to 500 degreesC. C1 Univ Calif San Diego, Dept Mech & Aerosp Engn, Chem Engn Program, La Jolla, CA 92093 USA. RP Maharrey, SP (reprint author), Sandia Natl Labs, POB 969,MS-9052, Livermore, CA 94551 USA. NR 33 TC 17 Z9 18 U1 2 U2 18 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 JUN 21 PY 2001 VL 105 IS 24 BP 5860 EP 5867 DI 10.1021/jp004512b PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 443YN UT WOS:000169371300020 ER PT J AU Metelski, PD Espenson, JH AF Metelski, PD Espenson, JH TI Kinetic and mechanism of reactions between methyl aromatic compounds and the dibromide radical SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID AQUEOUS-SOLUTION AB The dibromide radical (believed to be HBr2. in acetic acid) reacts with methylarenes, aldehydes, and carboxylic acids in acetic acid. The kinetics of these reactions were studied with the use of laser flash photolysis to generate the dibromide radical. The loss of the radical was monitored as a function of time at 360 nm. The data analysis requires an allowance for the concurrent bimolecular disproportionation reaction, 2HBr(2)(.) --> Br-2 + 2HBr, with k(d) = (2.2 +/- 0.5) x 10(9) L mol(-1) s(-1) at 23 degreesC. The reactions between HBr2. and substrate were first-order with respect to each concentration, with k between 4 x 10(3) (methyl-3-methylbenzoate) and 2 x 10(6) (hexamethylbenzene) L mol(-1) s(-1) at 23 OC. The variation of rate constant can be correlated with the reported rates for the overall catalytic conversions. Several compounds with deuterium labels in the methyl side chains were investigated. The presence of a significant kinetic isotope effect suggests that the reactions proceed by abstraction of a hydrogen atom from the a-carbon of the R-group on the aromatic residue. Ring substituents such as CHO and CO2H have a strong deactivating effect. C1 Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Dept Chem, Ames, IA 50011 USA. RP Espenson, JH (reprint author), Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. NR 17 TC 17 Z9 17 U1 0 U2 4 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5639 J9 J PHYS CHEM A JI J. Phys. Chem. A PD JUN 21 PY 2001 VL 105 IS 24 BP 5881 EP 5884 DI 10.1021/jp010311b PG 4 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 443YN UT WOS:000169371300023 ER PT J AU Autrey, T Kandanarachchi, P Franz, JA AF Autrey, T Kandanarachchi, P Franz, JA TI Comparison of diffusion coefficients of aryl carbonyls and aryl alcohols in hydroxylic solvents. Evidence that the diffusion of ketyl radicals in hydrogen-bonding solvents is not anomalous? SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID ABSOLUTE RATE EXPRESSIONS; TRANSIENT GRATING METHOD; ELECTRON-SPIN RESONANCE; TRANSLATIONAL DIFFUSION; RATE CONSTANTS; CENTERED RADICALS; ATOM ABSTRACTION; SELF-TERMINATION; LIGNIN; DIPHENYLPICRYLHYDRAZYL AB The diffusion coefficients of benzyl-, sec-phenethyl-, and diphenylmethyl alcohol and the corresponding arylcarbonyls (benzaldehyde, acetophenone, and benzophenone) were measured by Taylor's dispersion method in both ethyl and isopropyl alcohol. The experimental values are compared to published transient gracing measurements of the corresponding aryl ketyls (benzyl-; sec-phenethyl-, and diphenylmethyl-ketyl radical). The diffusion coefficients of the aryl alcohols are between 50 and 70% slower than the corresponding aryl ketones. The slower rate of diffusion is attributed to the capability of alcohol to participate as a hydrogen-bond donor with the solvent (ROH- - -O < (H)(R)). The ketone can only act as a weak hydrogen-bond, acceptor, lacking acidic hydrogens to participate in hydrogen-bonding interactions with the solvent. On the other hand, the diffusion coefficient of the aryl alcohols and the corresponding aryl ketyls are comparable within expected experimental error. This work shows that the diffusion of ketyl radicals is not anomalously slow and that aryl alcohols are significantly better models than the corresponding aryl ketones for analyzing the diffusion of aryl ketyls in both ethyl and isopropyl alcohol. The standard empirical recipes of Spernol-Wirtz and Wilke-Chang do not adequately account for the interactions between the solutes and the hydroxylic solvents ethyl and isopropyl alcohol. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Autrey, T (reprint author), Pacific NW Natl Lab, POB 999,MS K2-44, Richland, WA 99352 USA. NR 43 TC 10 Z9 10 U1 1 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5639 J9 J PHYS CHEM A JI J. Phys. Chem. A PD JUN 21 PY 2001 VL 105 IS 24 BP 5948 EP 5953 DI 10.1021/jp004291+ PG 6 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 443YN UT WOS:000169371300033 ER PT J AU Chandross, M Webb, EB Grest, GS Martin, MG Thompson, AP Roth, MW AF Chandross, M Webb, EB Grest, GS Martin, MG Thompson, AP Roth, MW TI Dynamics of exchange at gas-zeolite interfaces I: Pure component n-butane and isobutane SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID ELASTIC NEUTRON-SCATTERING; BIAS MONTE-CARLO; MOLECULAR-DYNAMICS; BRANCHED ALKANES; INTRACRYSTALLINE DIFFUSION; PHASE-EQUILIBRIA; ZSM-5 ZEOLITE; SIMULATION; SILICALITE; ADSORPTION AB We present the results of Molecular Dynamics and Monte Carlo simulations of n-butane and isobutane in silicalite. We begin with a comparison of the bulk adsorption and diffusion properties for two different parameterizations of the interaction potential between the hydrocarbon species, both of which have been shown to reproduce experimental gas-liquid coexistence curves. We examine diffusion as a function of the loading of the zeolite, as well as the temperature dependence of the diffusion constant at loading and for infinite dilution. Both force fields give accurate descriptions of bulk properties, We continue with simulations in which interfaces are formed between single component gases and the zeolite. After reaching equilibrium, we examine the dynamics of exchange between the bulk gas and the zeolite. In particular, we examine the average time spent in the adsorption layer by molecules as they enter the zeolite from the gas in an attempt to probe the microscopic origins of the surface barrier. The microscopic barrier is found to be insignificant for experimental systems. Finally, we calculate the permeability of the zeolite for n-butane and isobutane as a function of pressure. Our results underestimate the experimental results by an order of magnitude, indicating a strong effect from the surface barrier in these simulations, Our simulations are performed for a number of different gas temperatures and pressures, covering a wide range of state points. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Texas A&M Univ, Dept Phys & Life Sci, Corpus Christi, TX 78412 USA. RP Chandross, M (reprint author), Sandia Natl Labs, Mail Stop 1411, Albuquerque, NM 87185 USA. NR 50 TC 25 Z9 25 U1 0 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 JUN 21 PY 2001 VL 105 IS 24 BP 5700 EP 5712 DI 10.1021/jp002967v PG 13 WC Chemistry, Physical SC Chemistry GA 443YQ UT WOS:000169371500019 ER PT J AU Yotsombat, B Davydov, S Poolcharaunsin, P Vilaithong, T Brown, IG AF Yotsombat, B Davydov, S Poolcharaunsin, P Vilaithong, T Brown, IG TI Optical emission spectra of a copper plasma produced by a metal vapour vacuum arc plasma source SO JOURNAL OF PHYSICS D-APPLIED PHYSICS LA English DT Article; Proceedings Paper CT XVth Europhysucs Conference on ATomic and Molecular Physics of Ionized Gases CY AUG 26-30, 2000 CL LILLAFURED, HUNGARY SP European Phys Soc AB Optical emission spectroscopy in the range 200-800 nm was applied for investigation of the copper plasma produced by a metal vapour vacuum arc plasma source. The experiments were conducted for the cases when the plasma was guided by straight and Ohm -shaped curved solenoids as well as without solenoids, and also for different vacuum conditions. It was found that, besides singly- and doubly-charged ions, a relatively high concentration of excited neutral copper atoms was present in the plasma. The relative fraction of excited atoms was much higher in the region close to the cathode surface than in the plasma column inside the solenoid. The concentration of excited neutral. singly- and doubly-ionized atoms increased proportionally when the arc current was increased to 400 A. Some weak lines were attributed to more highly ionized copper species and impurities in the cathode material. C1 Chiang Mai Univ, Fac Sci, Dept Phys, Chiang Mai 50200, Thailand. Chiang Mai Univ, Inst Sci & Technol Res & Dev, Chiang Mai 50200, Thailand. Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Yotsombat, B (reprint author), Chiang Mai Univ, Fac Sci, Dept Phys, Chiang Mai 50200, Thailand. OI POOLCHARUANSIN, PHITSANU/0000-0001-9650-9888 NR 11 TC 8 Z9 9 U1 0 U2 5 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0022-3727 J9 J PHYS D APPL PHYS JI J. Phys. D-Appl. Phys. PD JUN 21 PY 2001 VL 34 IS 12 BP 1928 EP 1932 DI 10.1088/0022-3727/34/12/325 PG 5 WC Physics, Applied SC Physics GA 462MR UT WOS:000170424300028 ER PT J AU Markov, AV Mezhennyi, MV Polyakov, AY Smirnov, NB Govorkov, AV Eremin, VK Verbitskaya, EM Gavrin, VN Kozlova, YP Veretenkin, YP Bowles, TJ AF Markov, AV Mezhennyi, MV Polyakov, AY Smirnov, NB Govorkov, AV Eremin, VK Verbitskaya, EM Gavrin, VN Kozlova, YP Veretenkin, YP Bowles, TJ TI Semi-insulating LEC GaAs as a material for radiation detectors: materials science issues SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 2nd International Workshop on Radiation Imaging Detectors CY JUL 02-06, 2000 CL FREIBURG, GERMANY DE gallium arsenide; deep levels; radiation dectors ID PARTICLE DETECTORS; EL2 DEFECT; BULK; COMPENSATION; DIFFUSION; CRYSTALS; TRAPS AB Semi-insulating (SI) GaAs is now being reconsidered as a promising material for radiation detectors, mostly due to greatly improved quality of the material. In this paper we shall describe the properties of the state-of-the-art SI GaAs crystals grown by LEC method as relevant for such applications. Specifically, we shall concentrate on the assessment of the spectra and density of residual impurities, on the measurements of deep levels spectra and on studying the impact of these centers on material parameters. The spectra of deep centers as studied by PICTS and DLTS indicate that, in LEC crystals grown from stoichiometric melts, besides the most prominent EL2 center, other electron and hole traps are usually observed. By comparing the DLTS and PICTS results we show that PICTS often tends to overestimate the relative contributions of traps shallower than EL2. Two approaches to decreasing EL2 concentration in LEC grown crystals have been proposed in literature: to grow crystals from Ga-rich melts and to anneal the material at high temperatures. We have studied the changes in deep level spectra and transport parameters for both cases. In annealing experiments the possibility of thick samples modification by arsenic diffusion was also investigated. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Inst Chem Problems Microelect, Moscow, Russia. RAS, AF Ioffe Physicotech Inst, St Petersburg, Russia. RAS, Nucl Res Inst, Moscow 117901, Russia. Univ Calif Los Alamos Natl Lab, Los Alamos, NM USA. RP Polyakov, AY (reprint author), Inst Chem Problems Microelect, B Tolmachevsky 5, Moscow, Russia. RI Verbitskaya, Elena/D-1521-2014; Smirnov, Nickolai/K-8935-2015 OI Smirnov, Nickolai/0000-0002-4993-0175 NR 20 TC 11 Z9 14 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD JUN 21 PY 2001 VL 466 IS 1 BP 14 EP 24 DI 10.1016/S0168-9002(01)00819-1 PG 11 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 451EY UT WOS:000169789200004 ER PT J AU Gavrin, VN Kozlova, YP Veretenkin, EP Bowles, TJ Eremin, VK Verbitskaya, EM Markov, AV Polyakov, AY Koshelev, OG Morozova, VF AF Gavrin, VN Kozlova, YP Veretenkin, EP Bowles, TJ Eremin, VK Verbitskaya, EM Markov, AV Polyakov, AY Koshelev, OG Morozova, VF TI Bulk GaAs as a solar neutrino detector SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 2nd International Workshop on Radiation Imaging Detectors CY JUL 02-06, 2000 CL FREIBURG, GERMANY DE gallium arsenide; solar neutrino; large detector; native defect AB A GaAs detector may offer the unique possibility to independently study neutrino properties and solar physics. The ability to measure the flux of p-p, Be-7 and pep solar neutrinos would allow one to approach a solution of the "solar neutrino problem", i.e, the explanation of the significant deficit in observed capture rate of solar neutrinos. A large GaAs solar neutrino detector would allow to measure parameters for possible Mikheyev-Smirnov-Wolfenstein neutrino oscillations with unprecedented precision. A model-independent test for sterile neutrinos is also possible. A direct measurement of the temperature profile of the sun center appears feasible. A GaAs detector would also provide the ability to observe neutral current interactions in addition to addressing a wide range of other interesting physics. In order to measure the p-p, pep and Be-7 neutrinos a detector is required with low threshold (< 350 keV), good energy resolution (< 2 keV) and low background. A GaAs solid-state detector could meet the listed requirements. A large GaAs detector would be composed of approximately 40,000 intrinsic GaAs crystals, each weighting 3.2 kg. Such a detector would have a mass of 125 ton and would contain 60 ton of Ga occupying a volume of roughly 3 m on one side. Previous efforts by many groups have resulted in producing very small detectors with reasonably good resolution. However, it has thus far proved impossible to make large detectors with good resolution. Thus, a solar neutrino detector such as the one described above is obviously very ambitious, but the scientific motivation is sufficiently high that we have begun a research and development program with the goal of determining the technical feasibility of constructing large GaAs crystals with the requisite electronic properties to serve as particle detectors. <(c)> 2001 Elsevier Science B.V. All rights reserved. C1 Russian Acad Sci, Inst Nucl Res, Moscow, Russia. Univ Calif Los Alamos Natl Lab, Los Alamos, NM USA. Russian Acad Sci, AF Ioffe Physicotech Inst, St Petersburg, Russia. Inst Chem Problems Microelect, Moscow, Russia. Moscow State Univ, Moscow, Russia. RP Kozlova, YP (reprint author), Russian Acad Sci, Inst Nucl Res, 60Th October Anniversary Prospect 7, Moscow, Russia. RI Verbitskaya, Elena/D-1521-2014 NR 10 TC 2 Z9 3 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD JUN 21 PY 2001 VL 466 IS 1 BP 119 EP 125 DI 10.1016/S0168-9002(01)00834-8 PG 7 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 451EY UT WOS:000169789200019 ER PT J AU McGregor, DS Klann, RT Gersch, HK Yang, YH AF McGregor, DS Klann, RT Gersch, HK Yang, YH TI Thin-film-coated bulk GaAs detectors for thermal and fast neutron measurements SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 2nd International Workshop on Radiation Imaging Detectors CY JUL 02-06, 2000 CL FREIBURG, GERMANY DE neutron detector; semiconductor detector; radiation detector; neutron detection AB GaAs-based structures are presently under investigation as the substrate for B-10-coated and polyethylene-coated neutron detectors. The semi-insulating (SI) GaAs-based devices operate at low bias voltages by employing the truncated electric field effect, which allows for acceptable signals to be produced with bias voltages ranging between 10 and 50 V. At this time, the B-10-coated devices have demonstrated over 3.5% intrinsic thermal neutron detection efficiency with reactive films 1.8 mum thick. Relatively high neutron/gamma -ray rejection ratios can be achieved with an appropriate choice of lower level discriminator setting. Polyethylene-coated GaAs devices are being studied as fast neutron detectors and have shown evidence of (n,p) reactions for 14MeV neutrons. Theoretical neutron responses and experimental neutron detection data are presented and compared. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Michigan, Dept Nucl Engn & Radiol Sci, Ann Arbor, MI 48109 USA. Argonne Natl Lab, Argonne, IL 60439 USA. RP McGregor, DS (reprint author), Univ Michigan, Dept Nucl Engn & Radiol Sci, 2355 Bonisteel Blvd, Ann Arbor, MI 48109 USA. NR 25 TC 58 Z9 58 U1 0 U2 7 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 JUN 21 PY 2001 VL 466 IS 1 BP 126 EP 141 DI 10.1016/S0168-9002(01)00835-X PG 16 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 451EY UT WOS:000169789200020 ER PT J AU Chartier, M Beene, JR Blank, B Chen, L Galonsky, A Gan, N Govaert, K Hansen, PG Kruse, J Maddalena, V Thoennessen, M Varner, RL AF Chartier, M Beene, JR Blank, B Chen, L Galonsky, A Gan, N Govaert, K Hansen, PG Kruse, J Maddalena, V Thoennessen, M Varner, RL TI Identification of the Li-10 ground state SO PHYSICS LETTERS B LA English DT Article ID LIGHT-NUCLEI; NEUTRON; FRAGMENTATION; SPECTROSCOPY; BE-11 AB The proton-stripping reaction from a Be-11 radioactive beam incident on a beryllium target demonstrates that only (7 +/- 3)% of the Li-9 residues in the reaction are in coincidence with the 2.7 MeV gamma -ray corresponding to the Li-9 first excited state. This implies that the previously observed low-energy neutrons from the decay of the unbound nucleus Li-10 represent a direct l = 0 transition to the Li-9 ground state. Consequently, neutron-unbound Li-10 is proven to have the same parity inversion as occurs in the case of tin, with a 1s(1/2) intruder state below the natural parity 0p(1/2) state. Q 2001 Published by Elsevier Science B.V. C1 Michigan State Univ, Natl Superconducting Cyclotron Lab, E Lansing, MI 48824 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. CEN Bordeaux Gradignan, F-33175 Gradignan, France. RP Michigan State Univ, Natl Superconducting Cyclotron Lab, E Lansing, MI 48824 USA. EM chartier@cenbg.in2p3.fr NR 22 TC 36 Z9 36 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 EI 1873-2445 J9 PHYS LETT B JI Phys. Lett. B PD JUN 21 PY 2001 VL 510 IS 1-4 BP 24 EP 28 DI 10.1016/S0370-2693(01)00602-5 PG 5 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 446YT UT WOS:000169542300004 ER PT J AU Chekanov, S Derrick, M Krakauer, D Magill, S Musgrave, B Pellegrino, A Repond, J Stanek, R Yoshida, R Mattingly, MCK Antonioli, P Bari, G Basile, M Bellagamba, L Boscherini, D Bruni, A Bruni, G Romeo, GC Cifarelli, L Cindolo, F Contin, A Corradi, M De Pasquale, S Giusti, P Iacobucci, G Levi, G Margotti, A Massam, T Nania, R Palmonari, F Pesci, A Sartorelli, G Zichichi, A Aghuzumtsyan, G Brock, I Goers, S Hartmann, H Hilger, E Irrgang, P Jakob, HP Kappes, A Katz, UF Kerger, R Kind, O Paul, E Rautenberg, J Schnurbusch, H Stifutkin, A Tandler, J Voss, KC Weber, A Wieber, H Bailey, DS Brook, NH Cole, JE Foster, B Heath, GP Heath, HF Robins, S Rodrigues, E Scott, J Tapper, RJ Wing, M Capua, M Mastroberardino, A Schioppa, M Susinno, G Jeoung, HY Kim, JY Lee, JH Lim, IT Ma, KJ Pac, MY Caldwell, A Helbich, M Liu, W Liu, X Mellado, B Paganis, S Sampson, S Schmidke, WB Sciulli, F Chwastowski, J Eskreys, A Figiel, J Klimek, K Olkiewicz, K Przybycien, MB Stopa, P Zawiejski, L Bednarek, B Jelen, K Kisielewska, D Kowal, AM Kowal, M Kowalski, T Mindur, B Przybycien, M Rulikowska-Zarebska, E Suszycki, L Szuba, D Kotanski, A Bauerdick, LAT Behrens, U Borras, K Chiochia, V Crittenden, J Dannheim, D Desler, K Drews, G Fox-Murphy, A Fricke, U Geiser, A Goebel, F Gottlicher, P Graciani, R Haas, T Hain, W Hartner, GF Hebbel, K Hillert, S Koch, W Kotz, U Kowalski, H Labes, H Lohr, B Mankel, R Martens, J Martinez, M Milite, M Moritz, M Notz, D Petrucci, MC Polini, A Savin, AA Schneekloth, U Selonke, F Stonjek, S Wolf, G Wollmer, U Whitmore, JJ Wichmann, R Youngman, C Zeuner, W Coldewey, C Viani, ALD Meyer, A Schlenstedt, S Barbagli, G Gallo, E Pelfer, PG Bamberger, A Benen, A Coppola, N Markun, P Raach, H Wolfle, S Bell, M Bussey, PJ Doyle, AT Glasman, C Lee, SW Lupi, A McCance, GJ Saxon, DH Skillicorn, IO Bodmann, B Gendner, N Holm, U Salehi, H Wick, K Yildirim, A Ziegler, A Carli, T Garfagnini, A Gialas, I Lohrmann, E Foudas, C Goncalo, R Long, KR Metlica, F Miller, DB Tapper, AD Walker, R Cloth, P Filges, D Ishii, T Kuze, M Nagano, K Tokushuku, K Yamada, S Yamazaki, Y Barakbaev, AN Boos, EG Pokrovskiy, NS Zhautykov, BO Ahn, SH Lee, SB Park, SK Lim, H Son, D Barreiro, F Garcia, G Gonzalez, O Labarga, L del Peso, J Redondo, I Terron, J Vazquez, M Barbi, M Corriveau, F Padhi, S Stairs, DG Tsurugai, T Antonov, A Bashkirov, V Danilov, P Dolgoshein, BA Gladkov, D Sosnovtsev, V Suchkov, S Dementiev, RK Ermolov, PF Golubkov, YA Katkov, II Khein, LA Korotkova, NA Korzhavina, IA Kuzmin, VA Levchenko, BB Lukina, OY Proskuryakov, AS Shcheglova, LM Solomin, AN Vlasov, NN Zotkin, SA Bokel, C Botje, M Engelen, J Grijpink, S Koffeman, E Kooijman, P Schagen, S van Sighem, A Tassi, E Tiecke, H Tuning, N Velthuis, JJ Vossebeld, J Wiggers, L de Wolf, E Brummer, N Bylsma, B Durkin, LS Gilmore, J Ginsburg, CM Kim, CL Ling, TY Boogert, S Cooper-Sarkar, AM Devenish, RCE Ferrando, J Grosse-Knetter, J Matsushita, T Rigby, M Ruske, O Sutton, MR Walczak, R Bertolin, A Brugnera, R Carlin, R Dal Corso, F Dusini, S Limentani, S Longhin, A Parenti, A Posocco, M Stanco, L Turcato, M Adamczyk, L Iannotti, L Oh, BY Saull, PRB Toothacker, WS Iga, Y D'Agostini, G Marini, G Nigro, A Cormack, C Hart, JC McCubbin, NA Epperson, D Heusch, C Sadrozinski, HFW Seiden, A Williams, DC Park, IH Pavel, N Abramowicz, H Dagan, S Gaareen, A Kananov, S Kreisel, A Levy, A Abe, T Fusayasu, T Kehno, T Umemori, K Yamashita, T Hamatsu, R Hirose, T Inuzuka, M Kitamura, S Matsuzawa, K Nishimura, T Arneodo, M Cartiglia, N Cirio, R Costa, M Ferrero, MI Maselli, S Monaco, V Peroni, C Ruspa, M Sacchi, R Solano, A Staiano, A Bailey, DC Fagerstroem, CP Galea, R Koop, T Levman, GM Martin, JF Mirea, A Sabetfakhri, A Butterworth, JM Gwenlan, C Hayes, ME Heaphy, EA Jones, TW Lane, JB West, BJ Ciborowski, J Ciesielski, R Grzelak, G Nowak, RJ Pawlak, JM Plucinski, P Smalska, B Tymieniecka, T Ukleja, J Zakrzewski, JA Zarnecki, AF Adamus, M Sztuk, J Deppe, O Eisenberg, Y Gladilin, LK Hochman, D Karshon, U Breitweg, J Chapin, D Cross, R Kcira, D Lammers, S Reeder, DD Smith, WH Deshpande, A Dhawan, S Hughes, VW Straub, PB Bhadra, S Catterall, CD Frisken, WR Hall-Wilton, R Khakzad, M Menary, S AF Chekanov, S Derrick, M Krakauer, D Magill, S Musgrave, B Pellegrino, A Repond, J Stanek, R Yoshida, R Mattingly, MCK Antonioli, P Bari, G Basile, M Bellagamba, L Boscherini, D Bruni, A Bruni, G Romeo, GC Cifarelli, L Cindolo, F Contin, A Corradi, M De Pasquale, S Giusti, P Iacobucci, G Levi, G Margotti, A Massam, T Nania, R Palmonari, F Pesci, A Sartorelli, G Zichichi, A Aghuzumtsyan, G Brock, I Goers, S Hartmann, H Hilger, E Irrgang, P Jakob, HP Kappes, A Katz, UF Kerger, R Kind, O Paul, E Rautenberg, J Schnurbusch, H Stifutkin, A Tandler, J Voss, KC Weber, A Wieber, H Bailey, DS Brook, NH Cole, JE Foster, B Heath, GP Heath, HF Robins, S Rodrigues, E Scott, J Tapper, RJ Wing, M Capua, M Mastroberardino, A Schioppa, M Susinno, G Jeoung, HY Kim, JY Lee, JH Lim, IT Ma, KJ Pac, MY Caldwell, A Helbich, M Liu, W Liu, X Mellado, B Paganis, S Sampson, S Schmidke, WB Sciulli, F Chwastowski, J Eskreys, A Figiel, J Klimek, K Olkiewicz, K Przybycien, MB Stopa, P Zawiejski, L Bednarek, B Jelen, K Kisielewska, D Kowal, AM Kowal, M Kowalski, T Mindur, B Przybycien, M Rulikowska-Zarebska, E Suszycki, L Szuba, D Kotanski, A Bauerdick, LAT Behrens, U Borras, K Chiochia, V Crittenden, J Dannheim, D Desler, K Drews, G Fox-Murphy, A Fricke, U Geiser, A Goebel, F Gottlicher, P Graciani, R Haas, T Hain, W Hartner, GF Hebbel, K Hillert, S Koch, W Kotz, U Kowalski, H Labes, H Lohr, B Mankel, R Martens, J Martinez, M Milite, M Moritz, M Notz, D Petrucci, MC Polini, A Savin, AA Schneekloth, U Selonke, F Stonjek, S Wolf, G Wollmer, U Whitmore, JJ Wichmann, R Youngman, C Zeuner, W Coldewey, C Viani, ALD Meyer, A Schlenstedt, S Barbagli, G Gallo, E Pelfer, PG Bamberger, A Benen, A Coppola, N Markun, P Raach, H Wolfle, S Bell, M Bussey, PJ Doyle, AT Glasman, C Lee, SW Lupi, A McCance, GJ Saxon, DH Skillicorn, IO Bodmann, B Gendner, N Holm, U Salehi, H Wick, K Yildirim, A Ziegler, A Carli, T Garfagnini, A Gialas, I Lohrmann, E Foudas, C Goncalo, R Long, KR Metlica, F Miller, DB Tapper, AD Walker, R Cloth, P Filges, D Ishii, T Kuze, M Nagano, K Tokushuku, K Yamada, S Yamazaki, Y Barakbaev, AN Boos, EG Pokrovskiy, NS Zhautykov, BO Ahn, SH Lee, SB Park, SK Lim, H Son, D Barreiro, F Garcia, G Gonzalez, O Labarga, L del Peso, J Redondo, I Terron, J Vazquez, M Barbi, M Corriveau, F Padhi, S Stairs, DG Tsurugai, T Antonov, A Bashkirov, V Danilov, P Dolgoshein, BA Gladkov, D Sosnovtsev, V Suchkov, S Dementiev, RK Ermolov, PF Golubkov, YA Katkov, II Khein, LA Korotkova, NA Korzhavina, IA Kuzmin, VA Levchenko, BB Lukina, OY Proskuryakov, AS Shcheglova, LM Solomin, AN Vlasov, NN Zotkin, SA Bokel, C Botje, M Engelen, J Grijpink, S Koffeman, E Kooijman, P Schagen, S van Sighem, A Tassi, E Tiecke, H Tuning, N Velthuis, JJ Vossebeld, J Wiggers, L de Wolf, E Brummer, N Bylsma, B Durkin, LS Gilmore, J Ginsburg, CM Kim, CL Ling, TY Boogert, S Cooper-Sarkar, AM Devenish, RCE Ferrando, J Grosse-Knetter, J Matsushita, T Rigby, M Ruske, O Sutton, MR Walczak, R Bertolin, A Brugnera, R Carlin, R Dal Corso, F Dusini, S Limentani, S Longhin, A Parenti, A Posocco, M Stanco, L Turcato, M Adamczyk, L Iannotti, L Oh, BY Saull, PRB Toothacker, WS Iga, Y D'Agostini, G Marini, G Nigro, A Cormack, C Hart, JC McCubbin, NA Epperson, D Heusch, C Sadrozinski, HFW Seiden, A Williams, DC Park, IH Pavel, N Abramowicz, H Dagan, S Gaareen, A Kananov, S Kreisel, A Levy, A Abe, T Fusayasu, T Kehno, T Umemori, K Yamashita, T Hamatsu, R Hirose, T Inuzuka, M Kitamura, S Matsuzawa, K Nishimura, T Arneodo, M Cartiglia, N Cirio, R Costa, M Ferrero, MI Maselli, S Monaco, V Peroni, C Ruspa, M Sacchi, R Solano, A Staiano, A Bailey, DC Fagerstroem, CP Galea, R Koop, T Levman, GM Martin, JF Mirea, A Sabetfakhri, A Butterworth, JM Gwenlan, C Hayes, ME Heaphy, EA Jones, TW Lane, JB West, BJ Ciborowski, J Ciesielski, R Grzelak, G Nowak, RJ Pawlak, JM Plucinski, P Smalska, B Tymieniecka, T Ukleja, J Zakrzewski, JA Zarnecki, AF Adamus, M Sztuk, J Deppe, O Eisenberg, Y Gladilin, LK Hochman, D Karshon, U Breitweg, J Chapin, D Cross, R Kcira, D Lammers, S Reeder, DD Smith, WH Deshpande, A Dhawan, S Hughes, VW Straub, PB Bhadra, S Catterall, CD Frisken, WR Hall-Wilton, R Khakzad, M Menary, S CA ZEUS Collaboration TI Multiplicity moments in deep inelastic scattering at HERA SO PHYSICS LETTERS B LA English DT Article ID MONTE-CARLO GENERATOR; PHASE-SPACE BINS; QCD JETS; HIGH-ENERGY; MULTIPARTON CORRELATIONS; GENERALIZED DIMENSIONS; PARTON DISTRIBUTIONS; STRANGE ATTRACTORS; EVENT GENERATOR; HADRON SPECTRA AB Multiplicity moments of charged particles in deep inelastic e(+) p scattering have been measured with the ZEUS detector at HERA using an integrated luminosity of 38.3 pb(-1). The moments for Q(2) > 1000 GeV(2) were studied in the current region of the Breit frame. The evolution of the moments was investigated as a function of restricted regions in polar angle and, for the first time, both in the transverse momentum and in absolute momentum of final-state particles. Analytic perturbative QCD predictions in conjunction with the hypothesis of Local Parton-Hadron Duality (LPHD) reproduce the trends of the moments in polar-angle regions, although some discrepancies are observed. For the moments restricted either in transverse or absolute momentum, the analytic results combined with the LPHD hypothesis show considerable deviations from the measurements. The study indicates a large influence of the hadronisation stage on the multiplicity distributions in the restricted phase-space regions studied here, which is inconsistent with the expectations of the LPHD hypothesis. (C) 2001 Publishcd by Elsevier Science B.V. C1 Argonne Natl Lab, Argonne, IL 60439 USA. Andrews Univ, Berrien Springs, MI 49104 USA. Univ Bologna, I-40126 Bologna, Italy. Ist Nazl Fis Nucl, I-40126 Bologna, Italy. Univ Bonn, Inst Phys, D-5300 Bonn, Germany. Univ Bristol, HH Wills Phys Lab, Bristol BS8 1TL, Avon, England. Univ Calabria, Dept Phys, I-87030 Cosenza, Italy. Ist Nazl Fis Nucl, Cosenza, Italy. Chonnam Natl Univ, Kwangju 500757, South Korea. Columbia Univ, Nevis Labs, Irvington, NY USA. Inst Nucl Phys, PL-30055 Krakow, Poland. Acad Min & Met, Fac Phys & Nucl Tech, Krakow, Poland. Jagiellonian Univ, Dept Phys, PL-30059 Krakow, Poland. DESY, Deutsch Elektronen Zynchrotron, D-2000 Hamburg, Germany. DESY, Zeuthen, Germany. Univ Florence, I-50125 Florence, Italy. Ist Nazl Fis Nucl, I-50125 Florence, Italy. Univ Freiburg, Fak Phys, D-7800 Freiburg, Germany. Univ Glasgow, Dept Phys & Astron, Glasgow G12 8QQ, Lanark, Scotland. Univ Hamburg, Inst Expt Phys 1, D-2000 Hamburg, Germany. Univ Hamburg, Inst Expt Phys 2, D-2000 Hamburg, Germany. Univ London Imperial Coll Sci Technol & Med, High Energy Nucl Phys Grp, London SW7 2AZ, England. KEK, Inst Particle & Nucl Studies, Tsukuba, Ibaraki, Japan. Minist Educ & Sci Kazakhstan, Inst Phys & Technol, Alma Ata, Kazakhstan. Korea Univ, Seoul 136701, South Korea. Kyungpook Natl Univ, Taegu 702701, South Korea. Univ Autonoma Madrid, Dept Fis Teor, E-28049 Madrid, Spain. McGill Univ, Dept Phys, Montreal, PQ H3A 2T5, Canada. Meiji Gakuin Univ, Fac Gen Educ, Yokohama, Kanagawa, Japan. Moscow Phys Engn Inst, Moscow, Russia. Moscow MV Lomonosov State Univ, Inst Nucl Phys, Moscow 119899, Russia. NIKHEF H, NL-1009 DB Amsterdam, Netherlands. Univ Amsterdam, Amsterdam, Netherlands. Ohio State Univ, Dept Phys, Columbus, OH 43210 USA. Univ Oxford, Dept Phys, Oxford OX1 3NP, England. Univ Padua, Dipartimento Fis, I-35100 Padua, Italy. Ist Nazl Fis Nucl, I-35100 Padua, Italy. Penn State Univ, Dept Phys, University Pk, PA 16802 USA. Polytech Univ, Sagamihara, Kanagawa, Japan. Univ Roma La Sapienza, Dipartimento Fis, I-00185 Rome, Italy. Ist Nazl Fis Nucl, I-00185 Rome, Italy. Rutherford Appleton Lab, Didcot OX11 0QX, Oxon, England. Univ Calif Santa Cruz, Santa Cruz, CA 95064 USA. Seoul Natl Univ, Seoul 151742, South Korea. Univ Siegen, Fachbereich Phys, D-5900 Siegen, Germany. Tel Aviv Univ, Raymond & Beverly Sackler Fac Exact Sci, Sch Phys, IL-69978 Tel Aviv, Israel. Univ Tokyo, Dept Phys, Tokyo 113, Japan. Tokyo Metropolitan Univ, Dept Phys, Tokyo 19203, Japan. Univ Turin, Dipartimento Fis Sperimentale, I-10125 Turin, Italy. Ist Nazl Fis Nucl, I-10125 Turin, Italy. Univ Toronto, Dept Phys, Toronto, ON M5S 1A7, Canada. UCL, Dept Phys & Astron, London, England. Warsaw Univ, Inst Expt Phys, PL-00913 Warsaw, Poland. Inst Nucl Studies, PL-00681 Warsaw, Poland. Weizmann Inst Sci, Dept Particle Phys, IL-76100 Rehovot, Israel. Univ Wisconsin, Dept Phys, Madison, WI 53706 USA. Yale Univ, Dept Phys, New Haven, CT 06520 USA. York Univ, Dept Phys, Toronto, ON M3J 2R7, Canada. Loma Linda Univ, Loma Linda, CA 92350 USA. Univ Lodz, PL-90131 Lodz, Poland. RP Chekanov, S (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. RI De Pasquale, Salvatore/B-9165-2008; Wing, Matthew/C-2169-2008; Bashkirov, Vladimir/A-4818-2008; Doyle, Anthony/C-5889-2009; Ferrando, James/A-9192-2012; Golubkov, Yury/E-1643-2012; Levchenko, B./D-9752-2012; Proskuryakov, Alexander/J-6166-2012; Dementiev, Roman/K-7201-2012; Katz, Uli/E-1925-2013; Wiggers, Leo/B-5218-2015; Tassi, Enrico/K-3958-2015; Gladilin, Leonid/B-5226-2011; Solomin, Anatoly/C-3072-2016; Suchkov, Sergey/M-6671-2015; dusini, stefano/J-3686-2012; Goncalo, Ricardo/M-3153-2016; Graciani Diaz, Ricardo/I-5152-2016; Capua, Marcella/A-8549-2015; OI De Pasquale, Salvatore/0000-0001-9236-0748; Doyle, Anthony/0000-0001-6322-6195; Ferrando, James/0000-0002-1007-7816; Katz, Uli/0000-0002-7063-4418; Wiggers, Leo/0000-0003-1060-0520; Gladilin, Leonid/0000-0001-9422-8636; dusini, stefano/0000-0002-1128-0664; Goncalo, Ricardo/0000-0002-3826-3442; Graciani Diaz, Ricardo/0000-0001-7166-5198; Capua, Marcella/0000-0002-2443-6525; Longhin, Andrea/0000-0001-9103-9936; PAGANIS, STATHES/0000-0002-1950-8993 NR 43 TC 18 Z9 18 U1 1 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 JUN 21 PY 2001 VL 510 IS 1-4 BP 36 EP 54 DI 10.1016/S0370-2693(01)00583-4 PG 19 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 446YT UT WOS:000169542300006 ER PT J AU Iancu, E Leonidov, A McLerran, L AF Iancu, E Leonidov, A McLerran, L TI The renormalization group equation for the color glass condensate SO PHYSICS LETTERS B LA English DT Article ID GLUON DISTRIBUTION-FUNCTIONS; WEIZSACKER-WILLIAMS FIELDS; LOW X PHYSICS; BFKL POMERON; LARGE NUCLEUS; TRANSVERSE-MOMENTUM; PARTON DENSITY; QCD; COLLISIONS; EVOLUTION AB We present an explicit and simple form of the renormalization group equation which governs the quantum evolution of the effective theory for the Color Class Condensate (CGC). This is a functional Fokker-Planck equation for the probability density of the color field which describes the CGC in the covariant gauge. It is equivalent to the Euclidean time evolution equation for a second quantized current-current Hamiltonian in two spatial dimensions. The quantum corrections are included in the leading log approximation, but the equation is fully non-linear with respect to the generally strong background field. In the weak field limit, it reduces to the BFKL equation, while in the general non-linear case it generates the evolution equations for Wilson-line operators previously derived by Balitsky and Kovchegov within perturbative QCD. (C) 2001 Elsevier Science B.V. All rights reserved. C1 CEA Saclay, Serv Phys Theor, Lab, Direct Sci Mat, F-91191 Gif Sur Yvette, France. PN Lebedev Phys Inst, Moscow 117924, Russia. Brookhaven Natl Lab, Dept Phys, Upton, NY 11979 USA. RP Iancu, E (reprint author), CEA Saclay, Serv Phys Theor, Lab, Direct Sci Mat, F-91191 Gif Sur Yvette, France. RI Leonidov, Andrey/M-4440-2013 NR 38 TC 447 Z9 447 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 JUN 21 PY 2001 VL 510 IS 1-4 BP 133 EP 144 DI 10.1016/S0370-2693(01)00524-X PG 12 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 446YT UT WOS:000169542300015 ER PT J AU Iancu, E McLerran, L AF Iancu, E McLerran, L TI Saturation and universality in QCD at small x SO PHYSICS LETTERS B LA English DT Article ID WILSON RENORMALIZATION-GROUP; DEEP-INELASTIC SCATTERING; GLUON DISTRIBUTION-FUNCTIONS; ART. NO. 114023; BFKL POMERON; LARGE NUCLEI; PARTON DENSITY; EVOLUTION; UNITARIZATION; SINGULARITY AB We find approximate solutions to the renormalization group equation which governs the quantum evolution of the effective theory for the Color Glass Condensate. This is a functional Fokker-Planck equation which generates in particular the non-linear evolution equations previously derived by Balitsky and Kovchegov within perturbative QCD. In the limit where the transverse momentum of the external probe is large compared to the saturation momentum, our approximations yield the Gaussian ansatz for the effective action of the McLerran-Venugopalan model. In the opposite limit, of a small external momentum, we find that the effective theory is governed by a scale-invariant universal action which has the correct properties to describe gluon saturation. (C) 2001 Elsevier Science B.V. All rights reserved. C1 CEA Saclay, Serv Phys Theor, Lab, Direct Sci Mat, F-91191 Gif Sur Yvette, France. Brookhaven Natl Lab, Dept Phys, Upton, NY 11979 USA. RP Iancu, E (reprint author), CEA Saclay, Serv Phys Theor, Lab, Direct Sci Mat, F-91191 Gif Sur Yvette, France. NR 39 TC 181 Z9 181 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 J9 PHYS LETT B JI Phys. Lett. B PD JUN 21 PY 2001 VL 510 IS 1-4 BP 145 EP 154 DI 10.1016/S0370-2693(01)00526-3 PG 10 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 446YT UT WOS:000169542300016 ER PT J AU Son, DT Stephanov, MA Zhitnitsky, AR AF Son, DT Stephanov, MA Zhitnitsky, AR TI Instanton interactions in dense-matter QCD SO PHYSICS LETTERS B LA English DT Article ID COLOR-FLAVOR-LOCKING; SUPERCONDUCTIVITY; MASSES; PHASE AB A Coulomb gas representation of dense-matter QCD is derived from a dual transformation of the: low-energy effective Lagrangian. The point-like charges Q = +/-1 of the gas are identified with the instantons and anti-instantons of such topological charges. An instanton repels another instanton with the same force as it attracts an anti-instanton, in contrast to the semiclassical interaction. (C) 2001 Published by Elsevier Science B.V. C1 Columbia Univ, Dept Phys, New York, NY 10027 USA. Univ Illinois, Dept Phys, Chicago, IL 60607 USA. Univ British Columbia, Dept Phys & Astron, Vancouver, BC V6T 1Z1, Canada. Brookhaven Natl Lab, RIKEN BNL Res Ctr, Upton, NY 11973 USA. RP Son, DT (reprint author), Columbia Univ, Dept Phys, 538 W 120th St, New York, NY 10027 USA. NR 25 TC 26 Z9 26 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 J9 PHYS LETT B JI Phys. Lett. B PD JUN 21 PY 2001 VL 510 IS 1-4 BP 167 EP 172 DI 10.1016/S0370-2693(01)00607-4 PG 6 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 446YT UT WOS:000169542300019 ER PT J AU Sandi, G Brubaker, KL Schneider, JF O'Neill, HJ Cannon, PL AF Sandi, G Brubaker, KL Schneider, JF O'Neill, HJ Cannon, PL TI A coulometric iodimetric procedure for measuring the purity of lewisite SO TALANTA LA English DT Article DE arsenious acid; organic arsenic; lewisite AB A new analytical method for the determination of the purity of CASARM Lewisite samples (Chemical Agent Standard Analytical Reference Materials) has been developed and tested. The method essentially replaces the volumetric iodimetric procedures currently in use with the in-situ electrochemical generation of iodine. Tests on both arsenious acid and Lewisite/CVAA solutions show that the method is capable of achieving high accuracy and precision. Sample preparation and analysis times are considerably less than the current titrimetric method. The coulometric iodimetric method has been shown capable of determining not only total organic trivalent arsenic, but also total trivalent arsenic merely by adjusting the pH. Organic arsenic is determined at pH 4, and total trivalent arsenic at pH 8. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Argonne Natl Lab, Div Energy Syst, Argonne, IL 60439 USA. USA, Edgewood Chem & Biol Ctr, Aberdeen Proving Ground, MD 21010 USA. RP Brubaker, KL (reprint author), Argonne Natl Lab, Div Energy Syst, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 6 TC 3 Z9 4 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-9140 J9 TALANTA JI Talanta PD JUN 21 PY 2001 VL 54 IS 5 BP 913 EP 925 DI 10.1016/S0039-9140(01)00364-2 PG 13 WC Chemistry, Analytical SC Chemistry GA 452HL UT WOS:000169852200015 PM 18968315 ER PT J AU Zitzelsberger, H Bruch, J Smida, J Hieber, L Peddie, CM Bryant, PE Riches, AC Fung, JL Weier, HUG Bauchinger, M AF Zitzelsberger, H Bruch, J Smida, J Hieber, L Peddie, CM Bryant, PE Riches, AC Fung, JL Weier, HUG Bauchinger, M TI Clonal chromosomal aberrations in simian virus 40-transfected human thyroid cells and in derived tumors developed after in vitro irradiation SO INTERNATIONAL JOURNAL OF CANCER LA English DT Article DE in vitro model cell system; radiation-induced tumorigenesis; chromosomal aberration; comparative genomic hybridization; spectral karyotyping ID COMPARATIVE GENOMIC HYBRIDIZATION; RADIATION-INDUCED TRANSFORMATION; COPY NUMBER CHANGES; EPITHELIAL-CELLS; CELLULAR SENESCENCE; NEOPLASTIC TRANSFORMATION; INDEFINITE DIVISION; IONIZING-RADIATION; ALPHA-PARTICLES; SOLID TUMORS AB In vitro model cell systems are important tools for studying mechanisms of radiation-induced neoplastic transformation of human epithelial cells. In our study, the human thyroid epithelial cell line HTori-3 was analyzed cytogenetically following exposure to different doses of alpha- and gamma -irradiation and subsequent tumor formation in at athymic nude mice. Combining results from G-banding, comparative genomic hybridization, and spectral karyotyping, chromosome abnormalities could be depicted in the parental line HTori-3 and in nine different HTori lines established from the developed tumors. A number of chromosomal aberrations were found to be characteristic for simian virus 40 immortalization and/or radiation-induced transformation of human thyroid epithelial cells. Common chromosomal changes in cell lines originating from different irradiation experiments were loss of 8q23 and 13cen-q21 as well as gain of 1q32-qter and 2q11.2-q14.1. By comparison of chromosomal aberrations in cell lines exhibiting a different tumorigenic behavior, cytogenetic markers important for the tumorigenic process were studied. It appeared that deletions on chromosomes 9q32-q34 and 7q21-q31 as cs ell as an increased copy number of chromosome 20 were important for the tumorigenic phenotype. A comparative breakpoint analysis of the marker chromosomes found and those observed in radiation-induced childhood thyroid tumors from Belarus revealed a coincidence for a number of chromosome bands. Thus, the data support the usefulness of the established cell system as an in vitro model to study important steps during radiation-induced malignant transformation in human thyroid cells. (C) 2001 Wiley-Liss, Inc. C1 Lawrence Berkeley Lab, Div Life Sci, Berkeley, CA USA. Univ Calif San Francisco, Dept Obstet Gynecol, Reprod Sci Grp, San Francisco, CA 94143 USA. Univ St Andrews, Sch Biol, St Andrews, Fife, Scotland. Univ Munich, Inst Radiat Biol, Munich, Germany. GSF Forschungszentrum Umwelt & Gesundheit GMBH, Inst Radiobiol, Neuherberg, Germany. RP Zitzelsberger, H (reprint author), GSF Forschungszentrum Umwelt & Gesundheit GMBH, Inst Strahlenbiol, D-85758 Oberschleissheim, Germany. RI Smida, Jan/P-2486-2014 FU NIEHS NIH HHS [5-T32-ES07106-17] NR 38 TC 11 Z9 12 U1 0 U2 0 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC, 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0020-7136 J9 INT J CANCER JI Int. J. Cancer PD JUN 20 PY 2001 VL 96 IS 3 BP 166 EP 177 DI 10.1002/ijc.1015 PG 12 WC Oncology SC Oncology GA 439VG UT WOS:000169137800003 PM 11410885 ER PT J AU George, SD Metz, M Szilagyi, RK Wang, HX Cramer, SP Lu, Y Tolman, WB Hedman, B Hodgson, KO Solomon, EI AF George, SD Metz, M Szilagyi, RK Wang, HX Cramer, SP Lu, Y Tolman, WB Hedman, B Hodgson, KO Solomon, EI TI A quantitative description of the ground-state wave function of Cu-A by X-ray absorption spectroscopy: Comparison to plastocyanin and relevance to electron transfer SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID NITROUS-OXIDE REDUCTASE; BLUE COPPER SITE; 1.6 ANGSTROM RESOLUTION; LIGAND K-EDGE; CYTOCHROME-C; TUNNELING PATHWAYS; PARACOCCUS-DENITRIFICANS; THERMUS-THERMOPHILUS; NITRITE REDUCTASE; TRANSFER RATES AB To evaluate the importance of the electronic structure of CUA to its electron-transfer (ET) function, a quantitative description of the ground-state wave function of the mixed-valence (MV) binuclear Cu-A center engineered into Pseudomonas aeruginosa azurin has been developed, using a combination of S K-edge and Cu L-edge X-ray absorption spectroscopies (XAS). Parallel descriptions have been developed for a binuclear thiolate-bridged MV reference model complex ([((LCu)-Cu-iPrdacoS)(2)](+)) and a homovalent (II,II) analogue ([(LCu)-Cu-iPr2tacnS)(2)](2+), where L-iPrdacoS and L-iPr2tacnS are macrocyclic ligands with attached thiolates that bridge the Cu ions. Previous studies have qualitatively defined the ground-stare wave function of Cu-A in terms of ligand field effects on the orbital orientation and the presence of a metal-metal bond. The studies presented here provide further evidence for a direct Cu-Cu interaction and, importantly, experimentally quantify the covalency of the ground-state wave function. The experimental results are further supported by DFT calculations. The nature of the ground-state wave function of Cu-A is compared to that of the well-defined blue copper site in plastocyanin. and the importance of this wave function to the lower reorganization energy and ET function of Cu-A is discussed. This wave function incorporates anisotropic covalency into the intra- and intermolecular ET pathways in cytochrome c oxidase. Thus, the high covalency of the Cys-Cu bond allows a path through this ligand to become competitive with a shorter His path in the intramolecular ET from Cu-A to heme a and is particularly important for activating the intermolecular ET path from heme c to CUA. C1 Stanford Univ, Dept Chem, Stanford, CA 94305 USA. Univ Calif Davis, Dept Appl Sci, Davis, CA 95616 USA. Lawrence Berkeley Natl Lab, Phys Biosci Div, Berkeley, CA 94720 USA. Univ Illinois, Dept Chem, Urbana, IL 61801 USA. Univ Minnesota, Dept Chem, Minneapolis, MN 55455 USA. Univ Minnesota, Ctr Met Biocatalysis, Minneapolis, MN 55455 USA. Stanford Univ, Stanford Synchrotron Radiat Lab, SLAC, Stanford, CA 94309 USA. RP Hedman, B (reprint author), Stanford Univ, Dept Chem, Stanford, CA 94305 USA. RI Lu, Yi/B-5461-2010; DeBeer, Serena/G-6718-2012; Szilagyi, Robert/G-9268-2012 OI Lu, Yi/0000-0003-1221-6709; Szilagyi, Robert/0000-0002-9314-6222 NR 98 TC 92 Z9 92 U1 0 U2 21 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 JUN 20 PY 2001 VL 123 IS 24 BP 5757 EP 5767 DI 10.1021/ja004109i PG 11 WC Chemistry, Multidisciplinary SC Chemistry GA 443JQ UT WOS:000169338400020 ER PT J AU Bach, RD Baboul, AG Schlegel, HB AF Bach, RD Baboul, AG Schlegel, HB TI Inversion versus retention of configuration for nucleophilic substitution at vinylic carbon SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID SINGLE-STEP; HALIDES; ANIONS; S(N)2; MECHANISMS; CATIONS; MODEL AB A high-level computational study using CCSD, CCSD(T), and G2(+) levels of theory has shown that unactivated vinyl substrates such as vinyl chloride would afford gas phase, single-step halide exchange by a pure in-plane sigma -approach of the nucleophile to the backside of the C-CI sigma bond. Geometry optimization by CCSD/6-31+G* and CCSD(T)/6-31+G* confirms the earlier findings of Glukhovtsev, Press, and Radom that the S(N)2 reaction of Cl- with unactivated vinyl chloride in the gas phase occurs by a sigma attack. Complexation of vinyl chloride with Na+ does not alter this in-plane a preference. However, moderately activated dihaloethylenes such as 1-chloro-1-fluoroethylene undergo gas-phase S(N)2 aback by the accepted pi -route where the nucleophile approaches perpendicular to the plane of the C=C. In the latter case a single-step pi pathway is preferred for the Cl- + H2C=CFCl reaction. This is the first definitive example at a high level of theory where a single-step pi nucleophilic vinylic substitution is preferred over a multistep mechanism in the gas phase. The activation barriers for these gas-phase single-step sigma- and pi -processes involving both naked anions and Na+ complexes are, however, prohibitively high. Solvation and the presence of a counterion must play a dominant role in nucleophilic vinylic substitution reactions that proceed so readily in the condensed phase. In solution, nucleophilic vinylic substitution reactions involving electron-withdrawing groups on the carbon-carbon double bond (e.g., -CN, -CHO, and -NO2) would almost certainly proceed via a free discrete carbanionic intermediate in accord with experiment. C1 Wayne State Univ, Dept Chem, Detroit, MI 48202 USA. Univ Delaware, Dept Chem & Biochem, Newark, DE 19716 USA. Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. RP Schlegel, HB (reprint author), Wayne State Univ, Dept Chem, Detroit, MI 48202 USA. NR 48 TC 35 Z9 35 U1 1 U2 2 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 JUN 20 PY 2001 VL 123 IS 24 BP 5787 EP 5793 DI 10.1021/ja010234y PG 7 WC Chemistry, Multidisciplinary SC Chemistry GA 443JQ UT WOS:000169338400023 PM 11403613 ER PT J AU Gerisch, M Krumper, JR Bergman, RG Tilley, TD AF Gerisch, M Krumper, JR Bergman, RG Tilley, TD TI Novel bis(oxazoline) pincer ligands: Formation of mononuclear rhodium(II) complexes SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID X-RAY STRUCTURE; C-H; RUTHENIUM(II) COMPLEXES; POLYPHOSPHINE LIGANDS; ASYMMETRIC-SYNTHESIS; CRYSTAL-STRUCTURE; ORTHO METALATION; BOND-CLEAVAGE; REACTIVITY; ACTIVATION C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Ctr New Direct Organ Synth, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA. RP Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. NR 56 TC 59 Z9 59 U1 1 U2 6 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 JUN 20 PY 2001 VL 123 IS 24 BP 5818 EP 5819 DI 10.1021/ja005857a PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA 443JQ UT WOS:000169338400033 PM 11403623 ER PT J AU Harnisch, JA Pris, AD Porter, MD AF Harnisch, JA Pris, AD Porter, MD TI Attachment of gold nanoparticles to glassy carbon electrodes via a mercaptobenzene film SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID SELF-ASSEMBLED MONOLAYERS; ELECTROCHEMICAL REDUCTION; DIAZONIUM SALTS; FORCE MICROSCOPY; SURFACES; FABRICATION; PARTICLES; SUBSTRATE; TEMPLATES; SILVER C1 US DOE, Ames Lab, Microanalyt Instrumentat Ctr, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Dept Chem, Ames, IA 50011 USA. RP Porter, MD (reprint author), US DOE, Ames Lab, Microanalyt Instrumentat Ctr, Ames, IA 50011 USA. NR 29 TC 75 Z9 75 U1 1 U2 11 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 JUN 20 PY 2001 VL 123 IS 24 BP 5829 EP 5830 DI 10.1021/ja010564i PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA 443JQ UT WOS:000169338400038 PM 11403628 ER PT J AU Golden, JT Andersen, RA Bergman, RG AF Golden, JT Andersen, RA Bergman, RG TI Exceptionally low-temperature carbon-hydrogen/carbon-deuterium exchange reactions of organic and organometallic compounds catalyzed by the Cp*(PMe3)IrH(ClCH2Cl)(+) cation SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID C-H ACTIVATION; DIIMINE AQUA COMPLEX; BOND ACTIVATION; HYDROCARBON ACTIVATION; HYDROXYLIC SOLVENT; METAL-COMPLEXES; MILD CONDITIONS; IRIDIUM; TRIS(PENTAFLUOROPHENYL)BORANE; DERIVATIVES C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Chem, Ctr New Direct Organ Synth, Berkeley, CA 94720 USA. RP Andersen, RA (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA. NR 23 TC 111 Z9 111 U1 3 U2 8 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 JUN 20 PY 2001 VL 123 IS 24 BP 5837 EP 5838 DI 10.1021/ja0155480 PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA 443JQ UT WOS:000169338400042 PM 11403632 ER PT J AU Barrena, E Ocal, C Salmeron, M AF Barrena, E Ocal, C Salmeron, M TI A comparative AFM study of the structural and frictional properties of mixed and single component films of alkanethiols on Au(111) SO SURFACE SCIENCE LA English DT Article; Proceedings Paper CT 19th European Conference on Surface Science (ECOSS-19) CY SEP 05-08, 2000 CL MADRID, SPAIN SP Univ Autonoma Madrid, Dept Fis Mat Condensada, European Phys Soc, Surface & Interface Div, Int Union Vacuum Sci, Techni & Applicat, Surface Div DE atomic force microscopy; self-assembly; gold; friction ID SELF-ASSEMBLED MONOLAYERS; CHEMICAL FORCE MICROSCOPY; DISULFIDES; PRESSURE; GOLD AB A comparative study of the frictional and structural properties of single component films of alkanethiols, CnH2n-1SH (n = 12,16) and mixed films is presented. Islands instead of a complete monolayer are used to simultaneously measure film compression and friction under applied load. For single component films, the friction and film height change following a stepwise behavior. A simple geometrical model involving interlocking of the alkyl chains at specific molecular tilt angles explains the observations. At low loads the friction of single component films increases monotonously with the applied load. In contrast, in mixed films of C12 and C16 the friction force increases at it high rate first and then at the same rate as in single component films. We propose that the initial fast increase in friction is due to an energy dissipation mechanism based in the formation of gauche defects at the protruding ends of the long thiol molecules. (C) 2001 Elsevier Science B.V. All rights reserved. C1 CSIC, Inst Ciencia Mat Madrid, Madrid 28049, Spain. Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Ocal, C (reprint author), CSIC, Inst Ciencia Mat Madrid, Cantoblanco, Madrid 28049, Spain. RI Ocal, Carmen/G-8590-2013 OI Barrena, Esther/0000-0001-9163-2959; Ocal, Carmen/0000-0001-8790-8844 NR 16 TC 26 Z9 28 U1 0 U2 7 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 J9 SURF SCI JI Surf. Sci. PD JUN 20 PY 2001 VL 482 BP 1216 EP 1221 DI 10.1016/S0039-6028(01)00869-X PN 2 PG 6 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA 460HM UT WOS:000170302200077 ER PT J AU Nguyen, LH Espert, L Mechti, N Wilson, DM AF Nguyen, LH Espert, L Mechti, N Wilson, DM TI The human interferon- and estrogen-regulated ISG20/HEM45 gene product degrades single-stranded RNA and DNA in vitro SO BIOCHEMISTRY LA English DT Article ID CREB BINDING-PROTEIN; PML NUCLEAR-BODIES; ESCHERICHIA-COLI; MESSENGER-RNA; POLYMERASE-I; AMINO-ACID; CELLS; SITE; BODY; ENDONUCLEASE AB The human ISG20/HEM45 gene was identified independently on the basis of its increased level of expression in response to either interferon or estrogen hormone. Notably, the encoded protein is homologous with members of the 3' to 5' exonuclease superfamily that includes RNases T and D, and the proofreading domain of Escherichia coli DNA polymerase I. We provide here direct biochemical evidence that Isg20 acts as a 3' to 5' exonuclease in vitro. This protein displays a pH optimum of similar to7.0, prefers Mn2+ as a metal cofactor, and degrades RNA at a rate that is similar to 35-fold higher than its rate for single-stranded DNA. Along with RNase L, Isg20 is the second known RNase regulated by interferon. Previous data showed that Isg20 is located in promyelocytic leukemia (PML) nuclear bodies, known sites of hormone-dependent RNA polymerase II transcription and oncogenic DNA viral transcription and replication. The combined data suggest a potential role for Isg20 in degrading viral RNAs as part of the interferon-regulated antiviral response and/or cellular mRNAs as a regulatory component of interferon and estrogen signaling. C1 INSERM, U475, F-34197 Montpellier 5, France. Univ Calif Lawrence Livermore Natl Lab, Mol & Struct Biol Div, Livermore, CA 94551 USA. RP Wilson, DM (reprint author), INSERM, U475, 99 Rue Puech Villa, F-34197 Montpellier 5, France. FU NCI NIH HHS [CA79056] NR 29 TC 52 Z9 58 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0006-2960 J9 BIOCHEMISTRY-US JI Biochemistry PD JUN 19 PY 2001 VL 40 IS 24 BP 7174 EP 7179 DI 10.1021/bi010141t PG 6 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 443WU UT WOS:000169366000023 PM 11401564 ER PT J AU Pak, J Wunderlich, B AF Pak, J Wunderlich, B TI Melting and crystallization of polyethylene of different molar mass by calorimetry SO MACROMOLECULES LA English DT Article ID TEMPERATURE-MODULATED CALORIMETRY; SCANNING CALORIMETRY; HOMOGENEOUS NUCLEATION; SPHERULITIC GROWTH; THERMAL-ANALYSIS; CRYSTALS; TRANSITIONS; PARAFFINS; TMDSC AB Crystallization and melting of n-paraffins of chain lengths up to C60H122 can be largely reversible, and practically no supercooling is seen in differential scanning calorimetry (DSC) and temperature-modulated DSC (TMDSC). To find the changes with chain length for this effect, polyethlylene fractions of oligomers of mass 560, 1150, and 2150 Da and a polymer of mass 15 520 Da were analyzed. The mode of analysis was quasi-isothermal TMDSC: with an amplitude of 0.5 K about a fixed series of temperatures. For the oligomer of 560 Da, a mainly reversing melting was seen, similar to the behavior of paraffins of the same molar mass. The oligomer of 2150 Da as well as the polymer shows an irreversible crystallization with a crystallization of more than 5.0 K below the melting temperature, and the oligomer of 1150 Da is intermediate. Typical for polymers, a small amount of reversing material remains in the melting range of the polymer. The 1150 and the 2150 Da oligomers grow to extended-chain crystals, and the polymer yields folded-chain crystals. This research reveals that there is little difference in reversibility between monodisperse paraffins and fractions with similar average mass. There is no major difference in supercooling behavior for extended- and folded-chain crystals. The critical chain length for which a substantial supercooling is observed is 12.5 nm. The three types of reversible latent heat observed in macromolecules are traced to the short-chain molecules. C1 Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Wunderlich, B (reprint author), Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. NR 44 TC 69 Z9 69 U1 4 U2 23 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0024-9297 J9 MACROMOLECULES JI Macromolecules PD JUN 19 PY 2001 VL 34 IS 13 BP 4492 EP 4503 DI 10.1021/ma010195a PG 12 WC Polymer Science SC Polymer Science GA 442NH UT WOS:000169291500031 ER PT J AU Vargason, JM Henderson, K Ho, PS AF Vargason, JM Henderson, K Ho, PS TI A crystallographic map of the transition from B-DNA to A-DNA SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article ID ECCENTRIC E-DNA; CRYSTAL-STRUCTURE; NUCLEIC-ACIDS; DOUBLE HELIX; TATA-BOX; FORM; STABILIZATION; METHYLATION; REFINEMENT; RESOLUTION AB The transition between B- and A-DNA was first observed nearly 50 years ago. We have now mapped this transformation through a set of single-crystal structures of the sequence d(GGCGCC)(2), with various intermediates being trapped by methylating or brominating the cytosine bases. The resulting pathway progresses through 13 conformational steps, with a composite structure that pairs A-nucleotides with complementary B-nucleotides serving as a distinct transition intermediate. The details of each step in the conversion of B- to A-DNA are thus revealed at the atomic level, placing intermediates for this and other sequences in the context of a common pathway. C1 Oregon State Univ, Dept Biochem & Biophys, Corvallis, OR 97331 USA. Lawrence Berkeley Natl Lab, Macromol Crystallog Facil, Adv Light Source, Phys Biosci Div, Berkeley, CA 94720 USA. RP Ho, PS (reprint author), Oregon State Univ, Dept Biochem & Biophys, ALS 2011, Corvallis, OR 97331 USA. EM hops@ucs.orst.edu RI Ho, Pui/F-6186-2014 OI Ho, Pui/0000-0002-8082-4311 FU NIEHS NIH HHS [ES00210, P30 ES000210] NR 35 TC 77 Z9 79 U1 1 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 JUN 19 PY 2001 VL 98 IS 13 BP 7265 EP 7270 DI 10.1073/pnas.121176898 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 445KL UT WOS:000169456600051 PM 11390969 ER PT J AU Hlavacek, WS Redondo, A Metzger, H Wofsy, C Goldstein, B AF Hlavacek, WS Redondo, A Metzger, H Wofsy, C Goldstein, B TI Kinetic proofreading models for cell signaling predict ways to escape kinetic proofreading SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article ID HIGH-AFFINITY RECEPTOR; FC-EPSILON-RI; IGE RECEPTOR; MULTIVALENT ANTIGEN; TRANSDUCTION; AGGREGATION; MECHANISM; KINASES; PHOSPHORYLATION; DISSOCIATION AB In the context of cell signaling, kinetic proofreading was introduced to explain how cells can discriminate among ligands based on a kinetic parameter, the ligand-receptor dissociation rate constant. In the kinetic proofreading model of cell signaling, responses occur only when a bound receptor undergoes a complete series of modifications. If the ligand dissociates prematurely, the receptor returns to its basal state and signaling is frustrated. Mle extend the model to deal with systems where aggregation of receptors is essential to signal transduction, and present a version of the model for systems where signaling depends on an extrinsic kinase. We also investigate the kinetics of signaling molecules, "messengers." that are generated by aggregated receptors but do not remain associated with the receptor complex. We show that the extended model predicts modes of signaling that exhibit kinetic discriimination for some range of parameters but for other parameter values show little or no discrimination and thus escape kinetic proofreading. We compare model predictions with experimental data. C1 Univ Calif Los Alamos Natl Lab, Div Theoret, Theoret Biol & Biophys Grp, Los Alamos, NM 87545 USA. Univ Calif Los Alamos Natl Lab, Div Theoret, Theoret Chem Grp, Los Alamos, NM 87545 USA. NIAMSD, Arthrit & Rheumatism Branch, NIH, Bethesda, MD 20892 USA. Univ New Mexico, Dept Math & Stat, Albuquerque, NM 87131 USA. RP Goldstein, B (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, Theoret Biol & Biophys Grp, POB 1663, Los Alamos, NM 87545 USA. FU NIGMS NIH HHS [R01 GM035556, R37 GM035556, GM35556] NR 28 TC 39 Z9 40 U1 0 U2 3 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 JUN 19 PY 2001 VL 98 IS 13 BP 7295 EP 7300 DI 10.1073/pnas.121172298 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 445KL UT WOS:000169456600056 PM 11390967 ER PT J AU Wanke, MC Capasso, F Gmachl, C Tredicucci, A Sivco, DL Hutchinson, AL Chu, SNG Cho, AY AF Wanke, MC Capasso, F Gmachl, C Tredicucci, A Sivco, DL Hutchinson, AL Chu, SNG Cho, AY TI Injectorless quantum-cascade lasers SO APPLIED PHYSICS LETTERS LA English DT Article ID MU-M; PERFORMANCE AB An "injectorless" quantum-cascade (QC) laser is presented. The requirement of using injector regions to transport electrons from the lower laser level and other low-lying energy levels of one active region to the upper laser level of the next electron-downstream active region was eliminated by using an appropriately designed double-quantum-well "chirped" superlattice active region. The major advantage of the "injectorless" QC laser is the close packing of the active regions and the concomitant large optical confinement factor. Using a cascade of 75 consecutive active regions, designed for emission at lambda = 11.5 mum, a pulsed peak output power of 270 mW is achieved at 7 K and approximately 10 mW at the maximum operating temperature of 195 K. (C) 2001 American Institute of Physics. C1 Bell Labs, Lucent Technol, Murray Hill, NJ 07974 USA. RP Wanke, MC (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 16 TC 36 Z9 36 U1 0 U2 5 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD JUN 18 PY 2001 VL 78 IS 25 BP 3950 EP 3952 DI 10.1063/1.1378805 PG 3 WC Physics, Applied SC Physics GA 443KF UT WOS:000169339800009 ER PT J AU Micic, OI Ahrenkiel, SP Nozik, AJ AF Micic, OI Ahrenkiel, SP Nozik, AJ TI Synthesis of extremely small InP quantum dots and electronic coupling in their disordered solid films SO APPLIED PHYSICS LETTERS LA English DT Article ID SELF-ORGANIZATION; INDIUM-PHOSPHIDE; NANOCRYSTALS; EDGE; SUPERLATTICES; PRECURSORS; EMISSION; GAP AB Extremely small colloidal InP quantum dots (QDs) with diameters ranging from 15 to 23 Angstrom were synthesized, and the optical properties of close-packed arrays of these dots were studied. The isolated QDs in dilute colloidal solution exhibit pronounced discrete absorption spectra, indicating a narrow size distribution. The absorption spectra of close-packed solids of similar to 18 Angstrom diameter QDs with interdot spacings of 9 and 18 Angstrom show that the absorption onsets and excitonic peaks are, respectively, redshifted and broadened in going from dilute solution to close-packed Solids. These results can be explained by electron delocalization in disordered close-packed solids;the spacing of electronic levels in the QDs is reduced and produces a redshift in the absorption spectra. (C) 2001 American Institute of Physics. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Micic, OI (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. RI Nozik, Arthur/A-1481-2012; Nozik, Arthur/P-2641-2016 NR 26 TC 137 Z9 137 U1 0 U2 28 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD JUN 18 PY 2001 VL 78 IS 25 BP 4022 EP 4024 PG 3 WC Physics, Applied SC Physics GA 443KF UT WOS:000169339800033 ER PT J AU Lehmann, JF Dixon, DA Schrobilgen, GJ AF Lehmann, JF Dixon, DA Schrobilgen, GJ TI X-ray crystal structures of alpha-KrF2, [KrF][MF6] (M = As, Sb, Bi), [Kr2F3][SbF6]center dot KrF2, [Kr2F3](2)[SbF6](2)center dot KrF2, and [Kr2F3][AsF6]center dot[KrF][AsF6]; Synthesis and characterization of [Kr2F3][PF6]center dot nKrF(2); and theoretical studies of KrF2, KrF+, Kr2F3+, and the [KrF][MF6] (M = P, As, Sb, Bi) ion pairs SO INORGANIC CHEMISTRY LA English DT Article ID DENSITY-FUNCTIONAL THEORY; NMR SPECTROSCOPIC CHARACTERIZATION; NUCLEAR-MAGNETIC-RESONANCE; BOND ORDERS; RAMAN-SPECTROSCOPY; KRYPTON DIFLUORIDE; 1ST EXAMPLE; SCF THEORY; CATION; CHEMISTRY AB The crystal structures of alpha -KrF2 and salts containing the KrF+ and Kr2F3+ cations have been investigated for the first time using low-temperature single-crystal X-ray diffraction. The low-temperature a-phase of KrF2 crystallizes in the tetragonal space group I4/mmm with a = 4.1790(6) Angstrom, c = 6.489(1) Angstrom, Z = 2, V = 113.32(3) Angstrom (3), R-1 = 0.0231, and wR(2) = 0.0534 at -125 degreesC. The [KrF][MF6] (M = As, Sb, Pi) salts are isomorphous and isostructural and crystallize in the monoclinic space group P2(1)/c with Z = 4. The unit cell parameters are as follows: beta-[KrF]-[AsF6], a = 5.1753(2) Angstrom, b = 10.2019(7) Angstrom, c = 10.5763(8) Angstrom, beta = 95.298(2)degrees, V = 556.02(6) Angstrom (3), R-1= 0.0265, and wR(2) = 0.0652 at -120 degreesC; [KrF][SbF6], a 5.2922(6) Angstrom, b = 10.444(1) Angstrom, c 10.796(1) Angstrom, beta = 94.693(4)degrees, V = 594.73(1) Angstrom (3), R-1 = 0.0266, wR(2) = 0.0526 at -113 degreesC; [KrF][BiF6], a = 5.336(1) Angstrom, b = 10.513(2) Angstrom, c = 11.046(2) Angstrom, beta = 94.79(3)degrees, V = 617.6(2) Angstrom (3), R-1 = 0.0344, and wR(2) = 0.0912 at -130 degreesC. The Kr2F3+ cation was investigated in [Kr2F3][SbF6]. KrF2, [Kr2F3](2)[SbF6](2). KrF2, and [Kr2F3][AsF6]. [KrF][AsF6]. [Kr2F3](2)-[SbF6](2). KrF2 crystallizes in the monoclinic P2(1)/c space group with Z = 4 and a = 8.042(2) Angstrom, b = 30.815(6) Angstrom, c = 8.137(2) Angstrom, beta = 111.945(2) Angstrom, V = 1870.1(7) Angstrom (3), R-1 = 0.0376, and wR(2) = 0.0742 at -125 degreesC. [Kr2F3]-[SbF6]. KrF2 crystallizes in the triclinic P (1) over bar space group with Z = 2 and a = 8.032(3) Angstrom, b = 8.559(4) Angstrom, c = 8.948(4) Angstrom, alpha = 69.659(9)degrees, beta = 63.75(1)degrees, gamma = 82.60(1)degrees, V = 517.1(4) Angstrom (3), R-1 = 0.0402, and wR(2) = 0.1039 at -113 degreesC. [Kr2F3][AsF6]. [KrF][AsF6] crystallizes in the monoclinic space group P2(1)/c with Z = 4 and a = 6.247(1) Angstrom, b = 24.705(4) Angstrom, c = 8.8616(6) Angstrom, beta = 90.304(6)degrees, V = 1367.6(3) Angstrom (3), R-1 = 0.0471 and wR(2) = 0.0958 at -120 degreesC. The terminal Kr-F bond lengths of KrF+ and Kr2F3+ are very similar, exhibiting no crystallographically significant variation in the structures investigated (range, 1.765(3)-1.774(6) Angstrom and 1.780(7)-1.805(3) Angstrom in the KrF+ salts and from 2.027(5) to 2.065(4) Angstrom in the Kr2F3+ salts. The Kr-F bond lengths of KrF2 in [Kr2F3 ][SbF6]. KrF2 and [Kr2F3](2)[SbF6](2). KrF2 range from 1.868(4) to 1.888(4) Angstrom and are similar to those observed in alpha -KrF2 (1.894(5) Angstrom). The synthesis and Raman spectrum of the new salt, [Kr2F3][PF6]. nKrF(2), are also reported. Electron structure calculations at the Hartree-Fock and local density-functional theory levels were used to calculate the gas-phase geometries, charges, Mayer bond orders, and Mayer valencies of KrF+, KrF2, Kr2F3+, and the ion pairs, [KrF][MF6] (M = P, As, Sb, Bi), and to assign their experimental vibrational frequencies. C1 McMaster Univ, Dept Chem, Hamilton, ON L8S 4M1, Canada. Pacific NW Natl Lab, William R Wiley Environm Mol Sci Lab, Richland, WA 99352 USA. RP McMaster Univ, Dept Chem, 1280 Main St W, Hamilton, ON L8S 4M1, Canada. NR 89 TC 44 Z9 44 U1 0 U2 6 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0020-1669 EI 1520-510X J9 INORG CHEM JI Inorg. Chem. PD JUN 18 PY 2001 VL 40 IS 13 BP 3002 EP 3017 DI 10.1021/ic001167w PG 16 WC Chemistry, Inorganic & Nuclear SC Chemistry GA 443EQ UT WOS:000169327900012 PM 11399167 ER PT J AU Jiao, XD Metelski, PD Espenson, JH AF Jiao, XD Metelski, PD Espenson, JH TI Equilibrium and kinetics studies of reactions of manganese acetate, cobalt acetate, and bromide salts in acetic acid solutions SO INORGANIC CHEMISTRY LA English DT Article ID CRYSTAL-STRUCTURE; ORGANIC-COMPOUNDS; AUTOXIDATION; CATALYSIS; REDUCTION; OXIDATION; MECHANISM; RADICALS; CO(III); XYLENE AB The oxidation of hydrogen bromide and alkali metal bromide salts to bromine in;acetic acid by cobalt(III)acetate has been studied. The oxidation is inhibited by Mn(OAc)(2) and Co(OAc)(2), which lower the bromide concentration through complexation. Stability constants for Co(II)Br(n) were redetermined in acetic acid containing 0.1% water as a function of temperature. This amount of water lowers the stability constant values as compared to glacial acetic acid. Mn(II)Br(n) complexes were identified by UV-visible spectroscopy, and, the stability constants for Mn(II)Br(n), were determined by electrochemical methods. The kinetics of HBr oxidation shows that there is a new pathway in the presence of M(II)Br(n), Analysis of he concentration dependences shows that CoBr(2) and MnBr(2) are the principal and perhaps Bole forms of the divalent metals that react with Co(III) and Mn(III), The interpretation of these data is in terms of this step (M, N = Mn or Co): M(OAc)(3) + N(II)Br(2) + HOAc --> M(OAc)(2) + N(III)Br(2)OAc.The second-order rate constants (L mol(-1) s(-1)) for different M, N pairs in glacial acetic acid are 4.8 (Co, Co at 40 degreesC), 0.96 (Mn, Co at 20 degreesC), 0.15 (Mn(III). Co(II), Co at 20 degreesC), and 0.07 (Mn, Mn at 20 degreesC). Following that, reductive elimination of the dibromide radical is proposed to occur: N(III)Br(2)OAc + HOAc --> N(OAc)(2) + HBr(2)(.). This finding implicates the dibromide radical as a key intermediate in this chemistry, and indeed in the cobalt-bromide catalyzed autoxidation of methylarenes for which some form of zerovalent bromine has been identified. The selectivity for CoBr2 and MnBr2 is consistent with a pathway that forms this radical rather than bromine atoms which are at a considerably higher Gibbs energy. Mn(OAc)(3) oxidizes PhCH(2)Br, k = 1-3 L mol(-1) s(-1) at 50.0 degreesC in HOAc. C1 Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Chem, Ames, IA 50011 USA. RP Espenson, JH (reprint author), Iowa State Univ, Ames Lab, Ames, IA 50011 USA. NR 25 TC 10 Z9 10 U1 1 U2 19 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 JUN 18 PY 2001 VL 40 IS 13 BP 3228 EP 3233 DI 10.1021/ic0005801 PG 6 WC Chemistry, Inorganic & Nuclear SC Chemistry GA 443EQ UT WOS:000169327900042 PM 11399197 ER PT J AU Velthuis, SGET Felcher, GP Blomquist, P Wappling, R AF Velthuis, SGET Felcher, GP Blomquist, P Wappling, R TI Neutron spin rotation in magnetic mirror SO JOURNAL OF PHYSICS-CONDENSED MATTER LA English DT Article ID REFLECTOMETRY AB Polarized neutron reflectivity measurements on magnetic films, containing a magnetic collinear structure, yield simple and transparent information on the direction of the magnetization. Yet the phenomenology of the neutron spin behaviour is surprisingly rich. We show that, in the region of total reflection, films magnetized in a direction different from the neutron polarization axis cause a rotation of spin of the reflected neutrons that may be linearly dependent on the neutron momentum transfer. As a function of momentum transfer, the spin-analysed reflectivities oscillate with an amplitude directly linked to the angle between the polarization axis and the magnetization in the film. C1 Argonne Natl Lab, Argonne, IL 60439 USA. Univ Uppsala, Dept Phys, S-75121 Uppsala, Sweden. RP Velthuis, SGET (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. RI te Velthuis, Suzanne/I-6735-2013 OI te Velthuis, Suzanne/0000-0002-1023-8384 NR 10 TC 5 Z9 5 U1 0 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0953-8984 J9 J PHYS-CONDENS MAT JI J. Phys.-Condes. Matter PD JUN 18 PY 2001 VL 13 IS 24 BP 5577 EP 5583 DI 10.1088/0953-8984/13/24/303 PG 7 WC Physics, Condensed Matter SC Physics GA 449CE UT WOS:000169666100006 ER PT J AU Kinney, ER Cadman, RV Brack, J Cummings, WJ Fedchak, JA Fox, BD Gao, H Glockle, W Grosshauser, C Holt, RJ Jones, CE Miller, MA Nagengast, W Owen, BR Rith, K Schmidt, F Schulte, EC Sowinski, J Sperisen, F Thorsland, EL Tobey, R Wilbert, J Witala, H AF Kinney, ER Cadman, RV Brack, J Cummings, WJ Fedchak, JA Fox, BD Gao, H Glockle, W Grosshauser, C Holt, RJ Jones, CE Miller, MA Nagengast, W Owen, BR Rith, K Schmidt, F Schulte, EC Sowinski, J Sperisen, F Thorsland, EL Tobey, R Wilbert, J Witala, H TI Three-nucleon interactions: Evidence from polarized pd elastic scattering SO NUCLEAR PHYSICS A LA English DT Article; Proceedings Paper CT XVIIth European Conference on Few-Body Problems in Physics CY SEP 11-16, 2000 CL EVORA, PORTUGAL ID 3-NUCLEON FORCE; POTENTIAL MODELS; A(Y) PUZZLE; DEUTERIUM; (P)OVER-RIGHT-ARROW+D; EQUATIONS; MOMENTUM; ENERGIES; HYDROGEN; SYSTEMS AB Advances in precise computation of three-body reaction observables have spurred new interest in experimental measurements of proton deuteron elastic scattering, especially with regard to spin effects. Developments in spin-polarized internal targets for storage rings have permitted measurements of 197 MeV polarized protons scattering from vector polarized deuterons. This work presents measurements of the polarization observables A(y), iT(11), and C-y,C-y in proton-deuteron elastic scattering. When compared to calculations with and without three-nucleon forces, the measurements indicate that three-nucleon forces make a significant contribution to the observables. This work indicates that three-body forces derived from static nuclear properties appear to be crucial to the description of dynamical properties. C1 Univ Colorado, Nucl Phys Lab, Boulder, CO 80309 USA. Univ Illinois, Dept Phys, Urbana, IL 61801 USA. Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. MIT, Nucl Sci Lab, Cambridge, MA 02139 USA. Ruhr Univ Bochum, Inst Theoret Phys 2, D-44780 Bochum, Germany. Univ Erlangen Nurnberg, Inst Phys, D-91058 Erlangen, Germany. CALTECH, WK Kellogg Radiat Lab, Pasadena, CA 91125 USA. Indiana Univ, Cyclotron Facil, Bloomington, IN 47408 USA. Jagiellonian Univ, Inst Phys, PL-30059 Krakow, Poland. RP Kinney, ER (reprint author), Univ Colorado, Nucl Phys Lab, Boulder, CO 80309 USA. RI Gao, Haiyan/G-2589-2011; Holt, Roy/E-5803-2011 NR 35 TC 1 Z9 1 U1 0 U2 1 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 JUN 18 PY 2001 VL 689 IS 1-2 BP 33C EP 40C PG 8 WC Physics, Nuclear SC Physics GA 444JK UT WOS:000169396200005 ER PT J AU Gibson, BF AF Gibson, BF TI Hypernuclear physics, a brief past and bright future SO NUCLEAR PHYSICS A LA English DT Article; Proceedings Paper CT XVIIth European Conference on Few-Body Problems in Physics CY SEP 11-16, 2000 CL EVORA, PORTUGAL ID HYPERON-NUCLEON-INTERACTION; EXCHANGE-POTENTIAL APPROACH; BARYON-BARYON SCATTERING; HE-4(LAMBDA) DECAY; INTERACTION MODELS; WEAK DECAY; HYPERTRITON; OBSERVABLES; PARTICLE AB From its cosmic ray origins in 1952, interest in hypernuclear physics has focused upon the differences between conventional nuclei and their hypernuclear counterparts. Explored here are some of the unique aspects of few-baryon systems with non-zero strangeness, including features of the hyperon-nucleon interaction which distinguish it from the nucleon-nucleon force. Examined is the question of whether our models can extrapolate beyond the realm of conventional nuclear physics in which they were constructed or whether they are merely exquisite tools for interpolation within the world of zero strangeness. C1 Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. NR 68 TC 4 Z9 4 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 JUN 18 PY 2001 VL 689 IS 1-2 BP 57C EP 66C PG 10 WC Physics, Nuclear SC Physics GA 444JK UT WOS:000169396200008 ER PT J AU Schiavilla, R AF Schiavilla, R TI Electromagnetic structure of few-nucleon systems: a critical review SO NUCLEAR PHYSICS A LA English DT Article; Proceedings Paper CT XVIIth European Conference on Few-Body Problems in Physics CY SEP 11-16, 2000 CL EVORA, PORTUGAL ID RADIATIVE-CAPTURE; LOW ENERGIES; FREEDOM; CHARGE; FORCE AB Our current understanding of the structure of nuclei with A less than or equal to 8, including energy spectra, electromagnetic form factors, and capture reactions, is critically reviewed within the context of a realistic approach to nuclear dynamics based on two- and three-nucleon interactions and associated electromagnetic currents. C1 Jefferson Lab, Newport News, VA 23606 USA. Old Dominion Univ, Dept Phys, Norfolk, VA 23529 USA. RP Jefferson Lab, Newport News, VA 23606 USA. NR 21 TC 4 Z9 4 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 JUN 18 PY 2001 VL 689 IS 1-2 BP 84C EP 93C PG 10 WC Physics, Nuclear SC Physics GA 444JK UT WOS:000169396200011 ER PT J AU Gilman, R Brash, EJ AF Gilman, R Brash, EJ CA Jefferson Lab Hall A Collaboration TI Evidence for quark effects in high-energy d((gamma)over-right-arrow,(p)over-right-arrow)n SO NUCLEAR PHYSICS A LA English DT Article; Proceedings Paper CT XVIIth European Conference on Few-Body Problems in Physics CY SEP 11-16, 2000 CL EVORA, PORTUGAL ID C ANALYZING POWER; DEUTERON PHOTODISINTEGRATION; MODEL AB Recoil proton polarization was measured in deuteron photodisintegration at theta (cm) = 90 degrees for photon energies up to 2.5 GeV. The induced polarization p(y) is consistent with vanishing above 1 GeV, consistent with expectations from perturbative quantum chromodynamics (pQCD) and in disagreement with meson-baryon calculations. However, polarization transfer observables are non-zero, indicating that hadron helicity is not conserved. C1 Rutgers State Univ, Piscataway, NJ 08855 USA. Thomas Jefferson Natl Accelerator Lab, Newport News, VA 23606 USA. Univ Regina, Regina, SK S4S 0A2, Canada. RP Gilman, R (reprint author), Rutgers State Univ, Piscataway, NJ 08855 USA. NR 27 TC 0 Z9 0 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 JUN 18 PY 2001 VL 689 IS 1-2 BP 429C EP 432C PG 4 WC Physics, Nuclear SC Physics GA 444JK UT WOS:000169396200060 ER PT J AU Gilman, R AF Gilman, R CA Jefferson Lab E94 010 Collaboratio TI Generalized GDH sum and spin structure of He-3 and neutron SO NUCLEAR PHYSICS A LA English DT Article; Proceedings Paper CT XVIIth European Conference on Few-Body Problems in Physics CY SEP 11-16, 2000 CL EVORA, PORTUGAL ID SCATTERING; PROTON; G(2); RULE AB The generalized GDH sum rule allows a systematic study of the spin structure of the nucleon over a variety of scales, ranging from nucleon degrees of freedom at Q(2) = 0 to quark degrees of freedom at large Q(2). With existing measurements for both large Q(2) and real photons, interest has turned to the transition region between nucleon and quark degrees of freedom, for which no data exist. The Jefferson Lab E94-010 Collaboration has recently completed an experiment studying He-3((e) over right arrow, e ') for the transition region, Q(2) approximate to 0.1 to 1.0 GeV2. Missing mass coverage ranges from the elastic peak to deep inelastic scattering. The data allow extraction of the 3He and neutron spin structure functions, and of the generalized Gerasimov-Drell-Hearn (GDH) sum. C1 Rutgers State Univ, Piscataway, NJ 08855 USA. Thomas Jefferson Natl Accelerator Lab, Newport News, VA 23606 USA. RP Gilman, R (reprint author), Rutgers State Univ, Piscataway, NJ 08855 USA. NR 15 TC 2 Z9 2 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 JUN 18 PY 2001 VL 689 IS 1-2 BP 445C EP 448C PG 4 WC Physics, Nuclear SC Physics GA 444JK UT WOS:000169396200064 ER PT J AU Gross, F Drechsel, D Friar, J Pandharipande, V Sick, I AF Gross, F Drechsel, D Friar, J Pandharipande, V Sick, I TI Conference discussion of the nuclear few-body problem: questions and issues SO NUCLEAR PHYSICS A LA English DT Article; Proceedings Paper CT XVIIth European Conference on Few-Body Problems in Physics CY SEP 11-16, 2000 CL EVORA, PORTUGAL ID STRUCTURE-FUNCTION A(Q(2)); MONTE-CARLO CALCULATIONS; DEUTERON AB During the final session of the conference participants discussed important questions and issues from the current study of the nuclear few body problem. The discussion was preceded by five very short "mini-summaries" (limited to about 5 minutes each) presented by each member of the panel. These "mini-summaries" are presented in Sec. 1 below, and the questions and discussion is summarized in Sec. 2. The "mini-summaries" are presented in Sec. 1 in the order they were given to the conference. C1 Coll William & Mary, Jefferson Lab, Williamsburg, VA 23185 USA. Univ Mainz, Inst Kernphys, D-55099 Mainz, Germany. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Illinois, Dept Phys, Urbana, IL 61801 USA. Univ Basel, Inst Phys, CH-4056 Basel, Switzerland. RP Gross, F (reprint author), Coll William & Mary, Jefferson Lab, Williamsburg, VA 23185 USA. NR 8 TC 0 Z9 0 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 JUN 18 PY 2001 VL 689 IS 1-2 BP 573C EP 587C PG 15 WC Physics, Nuclear SC Physics GA 444JK UT WOS:000169396200093 ER PT J AU Binetruy, P Gaillard, MK Nelson, BD AF Binetruy, P Gaillard, MK Nelson, BD TI One loop soft supersymmetry breaking terms in superstring effective theories SO NUCLEAR PHYSICS B LA English DT Article ID PAULI-VILLARS REGULARIZATION; COUPLED STRING THEORY; GAUGE COUPLINGS; LINEAR MULTIPLET; SUPERGRAVITY; DILATON; CONDENSATION; MATTER; COMPACTIFICATIONS; FORMULATION AB We perform a systematic analysis of soft supersymmetry breaking terms at the one loop level in a large class of string effective field theories, This includes the so-called anomaly mediated contributions. We illustrate our results for several classes of orbifold models, In particular, we discuss a class of models where soft supersymmetry breaking terms are determined by quasi model independent anomaly mediated contributions, with possibly non-vanishing scalar masses at the one loop level. We show that the latter contribution depends on the detailed prescription of the regularization process which is assumed to represent the Planck scale physics of the underlying fundamental theory. The usual anomaly mediation case with vanishing scaler masses at one loop is not found to be generic. However gaugino masses and A-terms always vanish at tree level if supersymmetry breaking is moduli dominated with the moduli stabilized at self-dual points, whereas the vanishing of the B-term depends on the origin of the Ir-term in the underlying theory. We also discuss the supersymmetric spectrum of O-I and O-II models, as well as a model of gaugino condensation. For reference, explicit spectra corresponding to a Higgs mass of 114 GeV are given, Finally, we address general strategies for distinguishing among these models. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Paris 11, LPT, F-91405 Orsay, France. Univ Calif Berkeley, Lawrence Berkeley Lab, Theoret Phys Grp, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. RP Univ Paris 11, LPT, Bat 210, F-91405 Orsay, France. EM bdnelson@lbl.gov NR 49 TC 101 Z9 101 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 JUN 18 PY 2001 VL 604 IS 1-2 BP 32 EP 74 DI 10.1016/S0550-3213(00)00759-8 PG 43 WC Physics, Particles & Fields SC Physics GA 448EG UT WOS:000169613500002 ER PT J AU Csaki, C Erlich, J Grojean, C AF Csaki, C Erlich, J Grojean, C TI Gravitational Lorentz violations and adjustment of the cosmological constant in asymmetrically warped spacetimes SO NUCLEAR PHYSICS B LA English DT Review ID SUNDRUM BRANE WORLD; FLAT DOMAIN-WALLS; EXTRA DIMENSION; HIERARCHY PROBLEM; LIGHT VELOCITY; STANDARD MODEL; VARYING SPEED; CPT VIOLATION; 5D GRAVITY; INVARIANCE AB We investigate spacetimes in which the speed of light along flat 4D sections varies over the extra dimensions due to different warp factors for the space and the time coordinates ("asymmetrically warped" spacetimes). The main property of such spaces is that while the induced metric is flat, implying Lorentz invariant particle physics on a brane, bulk gravitational effects will cause apparent violations of Lorentz invariance and of causality from the brane observer's point of view. An important experimentally verifiable consequence of this is that gravitational waves may travel with a speed different from the speed of light on the brane, and possibly even faster. We find the most general spacetimes of this sort, which are given by AdS-Schwarzschild or AdS-Reissner-Nordstrom black holes, assuming the simplest possible sources in the bulk, Due to the gravitational Lorentz violations these models do not have an ordinary Lorentz invariant effective description, and thus provide a possible way around Weinberg's no-go theorem for the adjustment of the cosmological constant, Indeed we show that the cosmological constant may relax in such theories by the adjustment of the mass and the charge of the black hole. The black hole singularity in these solutions can be protected by a horizon, but the existence of a horizon requires some exotic energy densities on the brane, We investigate the cosmological expansion of these models and speculate that it may provide an explanation for the accelerating Universe, provided that the timescale for the adjustment is shorter than the Hubble time. In this case the accelerating Universe would be a manifestation of gravitational Lorentz violations in extra dimensions. Published by Elsevier Science B.V. C1 Univ Calif Los Alamos Natl Lab, Theory Div T8, Los Alamos, NM 87545 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Theoret Phys Grp, Berkeley, CA 94720 USA. NR 102 TC 174 Z9 174 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0550-3213 J9 NUCL PHYS B JI Nucl. Phys. B PD JUN 18 PY 2001 VL 604 IS 1-2 BP 312 EP 342 DI 10.1016/S0550-3213(01)00175-4 PG 31 WC Physics, Particles & Fields SC Physics GA 448EG UT WOS:000169613500010 ER PT J AU Fukuda, S Fukuda, Y Ishitsuka, M Itow, Y Kajita, T Kameda, J Kaneyuki, K Kobayashi, K Koshio, Y Miura, M Moriyama, S Nakahata, M Nakayama, S Okada, A Sakurai, N Shiozawa, M Suzuki, Y Takeuchi, H Takeuchi, Y Toshito, T Totsuka, Y Yamada, S Desai, S Earl, M Kearns, E Messier, MD Scholberg, K Stone, JL Sulak, LR Walter, CW Goldhaber, M Barszczak, T Casper, D Gajewski, W Kropp, WR Mine, S Liu, DW Price, LR Smy, MB Sobel, HW Vagins, MR Ganezer, KS Keig, WE Ellsworth, RW Tasaka, S Kibayashi, A Learned, JG Matsuno, S Takemori, D Hayato, Y Ishii, T Kobayashi, T Nakamura, K Obayashi, Y Oyama, Y Sakai, A Sakuda, M Kohama, M Suzuki, AT Inagaki, T Nakaya, T Nishikawa, K Haines, TJ Blaufuss, E Dazeley, S Lee, KB Svoboda, R Goodman, JA Guillian, G Sullivan, GW Turcan, D Habig, A Hill, J Jung, CK Martens, K Malek, M Mauger, C McGrew, C Sharkey, E Viren, B Yanagisawa, C Mitsuda, C Miyano, K Saji, C Shibata, T Kajiyama, Y Nagashima, Y Nitta, K Takita, M Yoshida, M Kim, HI Kim, SB Yoo, J Okazawa, H Ishizuka, T Etoh, M Gando, Y Hasegawa, T Inoue, K Ishihara, K Maruyama, T Shirai, J Suzuki, A Koshiba, M Hatakeyama, Y Ichikawa, Y Koike, M Nishijima, K Fujiyasu, H Ishino, H Morii, M Watanabe, Y Golebiewska, U Kielczewska, D Boyd, SC Stachyra, AL Wilkes, RJ Young, KK AF Fukuda, S Fukuda, Y Ishitsuka, M Itow, Y Kajita, T Kameda, J Kaneyuki, K Kobayashi, K Koshio, Y Miura, M Moriyama, S Nakahata, M Nakayama, S Okada, A Sakurai, N Shiozawa, M Suzuki, Y Takeuchi, H Takeuchi, Y Toshito, T Totsuka, Y Yamada, S Desai, S Earl, M Kearns, E Messier, MD Scholberg, K Stone, JL Sulak, LR Walter, CW Goldhaber, M Barszczak, T Casper, D Gajewski, W Kropp, WR Mine, S Liu, DW Price, LR Smy, MB Sobel, HW Vagins, MR Ganezer, KS Keig, WE Ellsworth, RW Tasaka, S Kibayashi, A Learned, JG Matsuno, S Takemori, D Hayato, Y Ishii, T Kobayashi, T Nakamura, K Obayashi, Y Oyama, Y Sakai, A Sakuda, M Kohama, M Suzuki, AT Inagaki, T Nakaya, T Nishikawa, K Haines, TJ Blaufuss, E Dazeley, S Lee, KB Svoboda, R Goodman, JA Guillian, G Sullivan, GW Turcan, D Habig, A Hill, J Jung, CK Martens, K Malek, M Mauger, C McGrew, C Sharkey, E Viren, B Yanagisawa, C Mitsuda, C Miyano, K Saji, C Shibata, T Kajiyama, Y Nagashima, Y Nitta, K Takita, M Yoshida, M Kim, HI Kim, SB Yoo, J Okazawa, H Ishizuka, T Etoh, M Gando, Y Hasegawa, T Inoue, K Ishihara, K Maruyama, T Shirai, J Suzuki, A Koshiba, M Hatakeyama, Y Ichikawa, Y Koike, M Nishijima, K Fujiyasu, H Ishino, H Morii, M Watanabe, Y Golebiewska, U Kielczewska, D Boyd, SC Stachyra, AL Wilkes, RJ Young, KK CA Super-Kamiokande Collaboration TI Solar B-8 and hep neutrino measurements from 1258 days of Super-Kamiokande data SO PHYSICAL REVIEW LETTERS LA English DT Article ID DECAY; OSCILLATIONS; SPECTRUM; FLUX; BETA AB Solar neutrino measurements from 1258 days of data from the Super-Kamiokande detector are presented. The measurements are based on recoil electrons in the energy range 5.0-20.0 MeV. The measured solar neutrino flux is 2.32 +/- 0.03(stat)(+0.08)(-0.07) (syst) x 10(6) cm(-2) s(-1) which is 45.1 +/- 0.5 (stat)(+1.6)(-1.4)(syst)% of that predicted by the BP2000 SSM. The day vs nieht flux asymmetry (Phi (n) - Phi (d)) / Phi (average) is 0.033 +/- 0.022(stat)(+0.013)(-0.012)(syst). The recoil electron energy spectrum is consistent with no spectral distortion. For the hep neutrino flux, we set a 90% C.L. upper limit of 40 x 10(3) cm(-2) s(-1) which is 4.3 times the BP2000 SSM prediction. C1 Univ Tokyo, Inst Cosm Ray Res, Kashiwa, Chiba 2778582, Japan. Boston Univ, Dept Phys, Boston, MA 02215 USA. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Univ Calif Irvine, Dept Phys & Astron, Irvine, CA 92697 USA. Calif State Univ Dominguez Hills, Dept Phys, Carson, CA 90747 USA. George Mason Univ, Dept Phys, Fairfax, VA 22030 USA. Gifu Univ, Dept Phys, Gifu 5011193, Japan. Univ Hawaii, Dept Phys & Astron, Honolulu, HI 96822 USA. High Energy Accelerator Res Org, Inst Particle & Nucl Studies, Tsukuba, Ibaraki 3050801, Japan. Kobe Univ, Dept Phys, Kobe, Hyogo 6578501, Japan. Kyoto Univ, Dept Phys, Kyoto 6068502, Japan. Los Alamos Natl Lab, Div Phys, Los Alamos, NM 87544 USA. Louisiana State Univ, Dept Phys & Astron, Baton Rouge, LA 70803 USA. Univ Maryland, Dept Phys, College Pk, MD 20742 USA. Univ Minnesota, Dept Phys, Duluth, MN 55812 USA. SUNY Stony Brook, Dept Phys & Astron, Stony Brook, NY 11794 USA. Niigata Univ, Dept Phys, Niigata 9502181, Japan. Osaka Univ, Dept Phys, Toyonaka, Osaka 5600043, Japan. Seoul Natl Univ, Dept Phys, Seoul 151742, South Korea. Shizuoka Seika Coll, Shizuoka 4258611, Japan. Shizuoka Univ, Dept Syst Engn, Hamamatsu, Shizuoka 4328561, Japan. Tohoku Univ, Res Ctr Neutrino Sci, Sendai, Miyagi 9808578, Japan. Univ Tokyo, Tokyo 1130033, Japan. Tokai Univ, Dept Phys, Hiratsuka, Kanagawa 2591292, Japan. Tokyo Inst Technol, Dept Phys, Tokyo 1528551, Japan. Univ Warsaw, Inst Expt Phys, PL-00681 Warsaw, Poland. Univ Washington, Dept Phys, Seattle, WA 98195 USA. RP Univ Tokyo, Inst Cosm Ray Res, Kashiwa, Chiba 2778582, Japan. RI Takeuchi, Yasuo/A-4310-2011; Nakamura, Kenzo/F-7174-2010; Obayashi, Yoshihisa/A-4472-2011; Yoo, Jonghee/K-8394-2016; Sobel, Henry/A-4369-2011; Suzuki, Yoichiro/F-7542-2010; Martens, Kai/A-4323-2011; Wilkes, R.Jeffrey/E-6011-2013; Kim, Soo-Bong/B-7061-2014; Sakurai, Nobuyuki/M-5009-2014; Ishino, Hirokazu/C-1994-2015; Koshio, Yusuke/C-2847-2015; Kibayashi, Atsuko/K-7327-2015 OI Sakurai, Nobuyuki/0000-0002-1002-217X; Ishino, Hirokazu/0000-0002-8623-4080; Koshio, Yusuke/0000-0003-0437-8505; NR 23 TC 868 Z9 871 U1 3 U2 38 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 JUN 18 PY 2001 VL 86 IS 25 BP 5651 EP 5655 DI 10.1103/PhysRevLett.86.5651 PG 5 WC Physics, Multidisciplinary SC Physics GA 443ZG UT WOS:000169373000004 PM 11415325 ER PT J AU Fukuda, S Fukuda, Y Ishitsuka, M Itow, Y Kajita, T Kameda, J Kaneyuki, K Kobayashi, K Koshio, Y Miura, M Moriyama, S Nakahata, M Nakayama, S Okada, A Sakurai, N Shiozawa, M Suzuki, Y Takeuchi, H Takeuchi, Y Toshito, T Totsuka, Y Yamada, S Desai, S Earl, M Kearns, E Messier, MD Scholberg, K Stone, JL Sulak, LR Walter, CW Goldhaber, M Barszczak, T Casper, D Gajewski, W Kropp, WR Mine, S Liu, DW Price, LR Smy, MB Sobel, HW Vagins, MR Ganezer, KS Keig, WE Ellsworth, RW Tasaka, S Kibayashi, A Learned, JG Matsuno, S Takemori, D Hayato, Y Ishii, T Kobayashi, T Nakamura, K Obayashi, Y Oyama, Y Sakai, A Sakuda, M Kohama, M Suzuki, AT Imagaki, T Nakaya, T Nishikawa, K Haines, TJ Blaufuss, E Dazeley, S Lee, KB Svoboda, R Goodman, JA Guillian, G Sullivan, GW Turcan, D Habig, A Hill, J Jung, CK Martens, K Malek, M Mauger, C McGrew, C Sharkey, E Viren, B Yanagisawa, C Mitsuda, C Miyano, K Saji, C Shibata, T Kajiyama, Y Nagashima, Y Nitta, K Takita, M Yoshida, M Kim, HI Kim, SB Yoo, J Okazawa, H Ishizuka, T Etoh, M Gando, Y Hasegawa, T Inoue, K Ishihara, K Maruyama, T Shirai, J Suzuki, A Koshiba, M Hatakeyama, Y Ichikawa, Y Koike, M Nishijima, K Fujiyasu, H Ishino, H Morii, M Watanabe, Y Golebiewska, U Kielczewska, D Boyd, SC Stachyra, AL Wilkes, RJ Young, KK AF Fukuda, S Fukuda, Y Ishitsuka, M Itow, Y Kajita, T Kameda, J Kaneyuki, K Kobayashi, K Koshio, Y Miura, M Moriyama, S Nakahata, M Nakayama, S Okada, A Sakurai, N Shiozawa, M Suzuki, Y Takeuchi, H Takeuchi, Y Toshito, T Totsuka, Y Yamada, S Desai, S Earl, M Kearns, E Messier, MD Scholberg, K Stone, JL Sulak, LR Walter, CW Goldhaber, M Barszczak, T Casper, D Gajewski, W Kropp, WR Mine, S Liu, DW Price, LR Smy, MB Sobel, HW Vagins, MR Ganezer, KS Keig, WE Ellsworth, RW Tasaka, S Kibayashi, A Learned, JG Matsuno, S Takemori, D Hayato, Y Ishii, T Kobayashi, T Nakamura, K Obayashi, Y Oyama, Y Sakai, A Sakuda, M Kohama, M Suzuki, AT Imagaki, T Nakaya, T Nishikawa, K Haines, TJ Blaufuss, E Dazeley, S Lee, KB Svoboda, R Goodman, JA Guillian, G Sullivan, GW Turcan, D Habig, A Hill, J Jung, CK Martens, K Malek, M Mauger, C McGrew, C Sharkey, E Viren, B Yanagisawa, C Mitsuda, C Miyano, K Saji, C Shibata, T Kajiyama, Y Nagashima, Y Nitta, K Takita, M Yoshida, M Kim, HI Kim, SB Yoo, J Okazawa, H Ishizuka, T Etoh, M Gando, Y Hasegawa, T Inoue, K Ishihara, K Maruyama, T Shirai, J Suzuki, A Koshiba, M Hatakeyama, Y Ichikawa, Y Koike, M Nishijima, K Fujiyasu, H Ishino, H Morii, M Watanabe, Y Golebiewska, U Kielczewska, D Boyd, SC Stachyra, AL Wilkes, RJ Young, KK CA Super-Kamiokande Collaboration TI Constraints on neutrino oscillations using 1258 days of Super-Kamiokande solar neutrino data SO PHYSICAL REVIEW LETTERS LA English DT Article ID ELECTRON SCATTERING; MODEL; DETECTOR; SPECTRUM; MATTER; NIGHT; SUN AB We report the result of a search for neutrino oscillations using precise measurements of the recoil electron energy spectrum and zenith angle variations of the solar neutrino flux from 1258 days of neutrino-electron scattering data in Super-Kamiokande. The absence of significant zenith angle variation and spectrum distortion places strong constraints on neutrino mixing and mass difference in a fluxin-dependent way. Using the Super-Kamiokande Aux measurement in addition, two allowed regions at large mixing are found. C1 Univ Tokyo, Inst Cosm Ray Res, Kashiwa, Chiba 2778582, Japan. Boston Univ, Dept Phys, Boston, MA 02215 USA. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Univ Calif Irvine, Dept Phys & Astron, Irvine, CA 92697 USA. Calif State Univ Dominguez Hills, Dept Phys, Carson, CA 90747 USA. George Mason Univ, Dept Phys, Fairfax, VA 22030 USA. Gifu Univ, Dept Phys, Gifu 5011193, Japan. Univ Hawaii, Dept Phys & Astron, Honolulu, HI 96822 USA. High Energy Accelerator Res Org, Inst Particle & Nucl Studies, Tsukuba, Ibaraki 3050801, Japan. Kobe Univ, Dept Phys, Kobe, Hyogo 6578501, Japan. Kyoto Univ, Dept Phys, Kyoto 6068502, Japan. Univ Calif Los Alamos Natl Lab, Div Phys, Los Alamos, NM 87544 USA. Louisiana State Univ, Dept Phys & Astron, Baton Rouge, LA 70803 USA. Univ Maryland, Dept Phys, College Pk, MD 20742 USA. Univ Minnesota, Dept Phys, Duluth, MN 55812 USA. SUNY Stony Brook, Dept Phys & Astron, Stony Brook, NY 11794 USA. Niigata Univ, Dept Phys, Niigata 9502181, Japan. Osaka Univ, Dept Phys, Toyonaka, Osaka 5600043, Japan. Seoul Natl Univ, Dept Phys, Seoul 151742, South Korea. Shizuoka Seika Coll, Shizuoka 4258611, Japan. Shizuoka Univ, Dept Syst Engn, Shizuoka 4328561, Japan. Tohoku Univ, Res Ctr Neutrino Sci, Sendai, Miyagi 9808578, Japan. Univ Tokyo, Tokyo 1130033, Japan. Tokai Univ, Dept Phys, Hiratsuka, Kanagawa 2591292, Japan. Tokyo Inst Technol, Dept Phys, Tokyo 1528551, Japan. Univ Warsaw, Inst Expt Phys, PL-00681 Warsaw, Poland. Univ Washington, Dept Phys, Seattle, WA 98195 USA. RP Scholberg, K (reprint author), Univ Tokyo, Inst Cosm Ray Res, Kashiwa, Chiba 2778582, Japan. RI Yoo, Jonghee/K-8394-2016; Takeuchi, Yasuo/A-4310-2011; Nakamura, Kenzo/F-7174-2010; Sobel, Henry/A-4369-2011; Suzuki, Yoichiro/F-7542-2010; Martens, Kai/A-4323-2011; Wilkes, R.Jeffrey/E-6011-2013; Kim, Soo-Bong/B-7061-2014; Sakurai, Nobuyuki/M-5009-2014; Ishino, Hirokazu/C-1994-2015; Koshio, Yusuke/C-2847-2015; Kibayashi, Atsuko/K-7327-2015; Obayashi, Yoshihisa/A-4472-2011 OI Sakurai, Nobuyuki/0000-0002-1002-217X; Ishino, Hirokazu/0000-0002-8623-4080; Koshio, Yusuke/0000-0003-0437-8505; NR 22 TC 606 Z9 606 U1 2 U2 27 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 JUN 18 PY 2001 VL 86 IS 25 BP 5656 EP 5660 DI 10.1103/PhysRevLett.86.5656 PG 5 WC Physics, Multidisciplinary SC Physics GA 443ZG UT WOS:000169373000005 PM 11415326 ER PT J AU Coan, TE Fadeyev, V Maravin, Y Narsky, I Stroynowski, R Ye, J Wlodek, T Artuso, M Ayad, R Boulahsuache, C Bukin, K Dambasuren, E Karamov, S Majumder, G Moneti, GC Mountain, R Schuh, S Skwarnicki, T Stone, S Viehhauser, G Wang, JC Wolf, A Wu, J Kopp, S Mahmood, AH Csorna, SE Danko, I McLean, KW Xu, Z Godang, R Bonvicini, G Cinabro, D Dubrovin, M McGee, S Zhou, GJ Lipeles, E Pappas, SP Schmidtler, M Shapiro, A Sun, WM Weinstein, AJ Wurthwein, F Jaffe, DE Masek, G Paar, HP Potter, EM Prell, S Asner, DM Eppich, A Hill, TS Morrison, RJ Briere, RA Chen, GP Ford, WT Gritsan, A Roy, J Smith, JG Alexander, JP Baker, R Bebek, C Berger, BE Berkelman, K Blanc, F Boisvert, V Cassel, DG Drell, PS Ecklund, KM Ehrlich, R Foland, AD Gaidarev, P Gibbons, L Gittelman, B Gray, SW Hartill, DL Heltsley, BK Hopman, PI Hsu, L Jones, CD Kandaswamy, J Kreinick, DL Lohner, M Magerkurth, A Meyer, TO Mistry, NB Nordberg, E Patterson, JR Peterson, D Riley, D Romano, A Thayer, JG Urner, D Valant-Spaight, B Warburton, A Avery, P Prescott, C Rubiera, AI Stoeck, H Yelton, J Brandenburg, G Ershov, A Gao, YS Kim, DYJ Wilson, R Bergfeld, T Eisenstein, BI Ernst, J Gladding, GE Gollin, GD Hans, RM Johnson, E Karliner, I Marsh, MA Palmer, T Plager, C Sedlack, C Selen, M Thaler, JJ Williams, J Edwards, KW Janicek, R Patel, PM Sadoff, AJ Ammar, R Bean, A Besson, D Zhao, X Anderson, S Frolov, VV Kubota, Y Lee, SJ Mahapatra, R O'Neill, JJ Poling, R Riehle, T Smith, A Stepaniak, CJ Urheim, J Ahmed, S Alam, MS Athar, SB Jian, L Ling, L Saleem, M Timm, S Wappler, F Anastassov, A Duboscq, JE Eckhart, E Gan, KK Gwon, C Hart, T Honscheid, K Hufnagel, D Kagan, H Kass, R Pedlar, TK Schwarthoff, H Thayer, JB von Toerne, E Zoeller, MM Richichi, SJ Severini, H Skubic, P Undrus, A Chen, S Fast, J Hinson, JW Lee, J Miller, DH Shibata, EI Shipsey, IPJ Pavlunin, V Cronin-Hennessy, D Lyon, AL Park, W Thorndike, EH Jessop, CP Savinov, V AF Coan, TE Fadeyev, V Maravin, Y Narsky, I Stroynowski, R Ye, J Wlodek, T Artuso, M Ayad, R Boulahsuache, C Bukin, K Dambasuren, E Karamov, S Majumder, G Moneti, GC Mountain, R Schuh, S Skwarnicki, T Stone, S Viehhauser, G Wang, JC Wolf, A Wu, J Kopp, S Mahmood, AH Csorna, SE Danko, I McLean, KW Xu, Z Godang, R Bonvicini, G Cinabro, D Dubrovin, M McGee, S Zhou, GJ Lipeles, E Pappas, SP Schmidtler, M Shapiro, A Sun, WM Weinstein, AJ Wurthwein, F Jaffe, DE Masek, G Paar, HP Potter, EM Prell, S Asner, DM Eppich, A Hill, TS Morrison, RJ Briere, RA Chen, GP Ford, WT Gritsan, A Roy, J Smith, JG Alexander, JP Baker, R Bebek, C Berger, BE Berkelman, K Blanc, F Boisvert, V Cassel, DG Drell, PS Ecklund, KM Ehrlich, R Foland, AD Gaidarev, P Gibbons, L Gittelman, B Gray, SW Hartill, DL Heltsley, BK Hopman, PI Hsu, L Jones, CD Kandaswamy, J Kreinick, DL Lohner, M Magerkurth, A Meyer, TO Mistry, NB Nordberg, E Patterson, JR Peterson, D Riley, D Romano, A Thayer, JG Urner, D Valant-Spaight, B Warburton, A Avery, P Prescott, C Rubiera, AI Stoeck, H Yelton, J Brandenburg, G Ershov, A Gao, YS Kim, DYJ Wilson, R Bergfeld, T Eisenstein, BI Ernst, J Gladding, GE Gollin, GD Hans, RM Johnson, E Karliner, I Marsh, MA Palmer, T Plager, C Sedlack, C Selen, M Thaler, JJ Williams, J Edwards, KW Janicek, R Patel, PM Sadoff, AJ Ammar, R Bean, A Besson, D Zhao, X Anderson, S Frolov, VV Kubota, Y Lee, SJ Mahapatra, R O'Neill, JJ Poling, R Riehle, T Smith, A Stepaniak, CJ Urheim, J Ahmed, S Alam, MS Athar, SB Jian, L Ling, L Saleem, M Timm, S Wappler, F Anastassov, A Duboscq, JE Eckhart, E Gan, KK Gwon, C Hart, T Honscheid, K Hufnagel, D Kagan, H Kass, R Pedlar, TK Schwarthoff, H Thayer, JB von Toerne, E Zoeller, MM Richichi, SJ Severini, H Skubic, P Undrus, A Chen, S Fast, J Hinson, JW Lee, J Miller, DH Shibata, EI Shipsey, IPJ Pavlunin, V Cronin-Hennessy, D Lyon, AL Park, W Thorndike, EH Jessop, CP Savinov, V CA CLEO Collaboration TI Bounds on the CP asymmetry in b -> s gamma decays SO PHYSICAL REVIEW LETTERS LA English DT Article ID B->X-S-GAMMA; SIGNATURE; DETECTOR AB We have measured the CP asymmetry A(CP) equivalent to [Gamma (b --> sy) - Gamma((b) over bar --> ($) over bar gamma)]/[Gamma (b --> s gamma) + Gamma((b) over bar --> (s) over bar gamma)] to be A(CP) = (-0.079 +/- 0.108 +/- 0.022)(1.0 +/- 0.030), implying that, at 90% confidence level, A(CP) lies between -0.27 and +/- 0.10. These limits rule out some extreme non-standard-model predictions, but are consistent with most, as well as with the standard model. C1 So Methodist Univ, Dallas, TX 75275 USA. Syracuse Univ, Syracuse, NY 13244 USA. Univ Texas, Austin, TX 78712 USA. Univ Texas Pan Amer, Edinburg, TX 78539 USA. Vanderbilt Univ, Nashville, TN 37235 USA. Virginia Polytech Inst & State Univ, Blacksburg, VA 24061 USA. Wayne State Univ, Detroit, MI 48202 USA. CALTECH, Pasadena, CA 91125 USA. Univ Calif San Diego, La Jolla, CA 92093 USA. Univ Calif Santa Barbara, Santa Barbara, CA 93106 USA. Carnegie Mellon Univ, Pittsburgh, PA 15213 USA. Univ Colorado, Boulder, CO 80309 USA. Cornell Univ, Ithaca, NY 14853 USA. Univ Florida, Gainesville, FL 32611 USA. Harvard Univ, Cambridge, MA 02138 USA. Univ Illinois, Urbana, IL 61801 USA. Carleton Univ, Ottawa, ON K1S 5B6, Canada. Inst Particle Phys, Ottawa, ON, Canada. McGill Univ, Montreal, PQ H3A 2T8, Canada. Ithaca Coll, Ithaca, NY 14850 USA. Univ Kansas, Lawrence, KS 66045 USA. Univ Minnesota, Minneapolis, MN 55455 USA. SUNY Albany, Albany, NY 12222 USA. Ohio State Univ, Columbus, OH 43210 USA. Univ Oklahoma, Norman, OK 73019 USA. Purdue Univ, W Lafayette, IN 47907 USA. Univ Rochester, Rochester, NY 14627 USA. Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Coan, TE (reprint author), So Methodist Univ, Dallas, TX 75275 USA. RI Warburton, Andreas/N-8028-2013; Briere, Roy/N-7819-2014; OI Warburton, Andreas/0000-0002-2298-7315; Briere, Roy/0000-0001-5229-1039; Bean, Alice/0000-0001-5967-8674 NR 10 TC 48 Z9 48 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 JUN 18 PY 2001 VL 86 IS 25 BP 5661 EP 5665 DI 10.1103/PhysRevLett.86.5661 PG 5 WC Physics, Multidisciplinary SC Physics GA 443ZG UT WOS:000169373000006 PM 11415327 ER PT J AU Liyanage, N Anderson, BD Aniol, KA Auerbach, L Baker, FT Berthot, J Bertozzi, W Bertin, PY Bimbot, L Boeglin, WU Brash, EJ Breton, V Breuer, H Burtin, E Calarco, JR Cardman, L Cates, GD Cavata, C Chang, CC Chen, JP Cisbani, E Dale, DS De Leo, R Deur, A Diederich, B Djawotho, P Domingo, J Doyle, B Ducret, JE Epstein, MB Ewell, LA Finn, JM Fissum, KG Fonvieille, H Frois, B Frullani, S Gao, J Garibaldi, F Gasparian, A Gilad, S Gilman, R Glamazdin, A Glashausser, C Gomez, J Gorbenko, V Gorringe, T Hersman, FW Holmes, R Holtrop, M d'Hose, N Howell, C Huber, GM Hyde-Wright, CE Iodice, M de Jager, CW Jaminion, S Jones, MK Joo, K Jutier, C Kahl, W Kato, S Kelly, JJ Kerhoas, S Khandaker, M Khayat, M Kino, K Korsch, W Kramer, L Kumar, KS Kumbartzki, G Laveissiere, G Leone, A LeRose, JJ Levchuk, L Liang, M Lindgren, RA Lolos, GJ Lourie, RW Madey, R Maeda, K Malov, S Manley, DM Margaziotis, DJ Markowitz, P Martino, J McCarthy, JS McCormick, K McIntyre, J van der Meer, RLJ Meziani, ZE Michaels, R Mougey, J Nanda, S Neyret, D Offermann, EAJM Papandreou, Z Perdrisat, CF Perrino, R Petratos, GG Platchkov, S Pomatsalyuk, R Prout, DL Punjabi, VA Pussieux, T Quemener, G Ransome, RD Ravel, O Roblin, Y Roche, R Rowntree, D Rutledge, GA Rutt, PM Saha, A Saito, T Sarty, AJ Serdarevic-Offermann, A Smith, TP Soldi, A Sorokin, P Souder, P Suleiman, R Templon, JA Terasawa, T Todor, L Tsubota, H Ueno, H Ulmer, PE Urciuoli, GM Vernin, P van Verst, S Vlahovic, B Voskanyan, H Watson, JW Weinstein, LB Wijesooriya, K Wilson, R Wojtsekhowski, B Zainea, DG Zeps, V Zhao, J Zhou, ZL AF Liyanage, N Anderson, BD Aniol, KA Auerbach, L Baker, FT Berthot, J Bertozzi, W Bertin, PY Bimbot, L Boeglin, WU Brash, EJ Breton, V Breuer, H Burtin, E Calarco, JR Cardman, L Cates, GD Cavata, C Chang, CC Chen, JP Cisbani, E Dale, DS De Leo, R Deur, A Diederich, B Djawotho, P Domingo, J Doyle, B Ducret, JE Epstein, MB Ewell, LA Finn, JM Fissum, KG Fonvieille, H Frois, B Frullani, S Gao, J Garibaldi, F Gasparian, A Gilad, S Gilman, R Glamazdin, A Glashausser, C Gomez, J Gorbenko, V Gorringe, T Hersman, FW Holmes, R Holtrop, M d'Hose, N Howell, C Huber, GM Hyde-Wright, CE Iodice, M de Jager, CW Jaminion, S Jones, MK Joo, K Jutier, C Kahl, W Kato, S Kelly, JJ Kerhoas, S Khandaker, M Khayat, M Kino, K Korsch, W Kramer, L Kumar, KS Kumbartzki, G Laveissiere, G Leone, A LeRose, JJ Levchuk, L Liang, M Lindgren, RA Lolos, GJ Lourie, RW Madey, R Maeda, K Malov, S Manley, DM Margaziotis, DJ Markowitz, P Martino, J McCarthy, JS McCormick, K McIntyre, J van der Meer, RLJ Meziani, ZE Michaels, R Mougey, J Nanda, S Neyret, D Offermann, EAJM Papandreou, Z Perdrisat, CF Perrino, R Petratos, GG Platchkov, S Pomatsalyuk, R Prout, DL Punjabi, VA Pussieux, T Quemener, G Ransome, RD Ravel, O Roblin, Y Roche, R Rowntree, D Rutledge, GA Rutt, PM Saha, A Saito, T Sarty, AJ Serdarevic-Offermann, A Smith, TP Soldi, A Sorokin, P Souder, P Suleiman, R Templon, JA Terasawa, T Todor, L Tsubota, H Ueno, H Ulmer, PE Urciuoli, GM Vernin, P van Verst, S Vlahovic, B Voskanyan, H Watson, JW Weinstein, LB Wijesooriya, K Wilson, R Wojtsekhowski, B Zainea, DG Zeps, V Zhao, J Zhou, ZL CA Jefferson Lab Hall A Collaboration TI Dynamics of the O-16(e,e(l)p) reaction at high missing energies SO PHYSICAL REVIEW LETTERS LA English DT Article ID ELECTRON-SCATTERING; REACTION C-12(E,E'P); MOMENTUM-TRANSFER; CROSS-SECTIONS; KNOCKOUT; NUCLEI; TARGET; REGION; SHELL; C-12 AB We measured the cross section and response functions for the quasielastic O-16(e, e 'p) reaction for missing energies 25 less than or equal to E-m less than or equal to 120 MeV at missing momenta P-m less than or equal to 340 MeV/c. For 25 < E-m < 50 MeV and P-m approximate to 60 MeV/c, the reaction is dominated by a single ls(1/2) proton knockout. At larger P-m, the single-particle aspects are increasingly masked by more complicated processes. Calculations which include pion exchange currents, isobar currents, and short-range correlations account for the shape and the transversity, but for only half of the magnitude of the measured cross section. C1 MIT, Cambridge, MA 02139 USA. Univ Clermont Ferrand 2, IN2P3, F-63177 Clermont Ferrand, France. Calif State Univ Los Angeles, Los Angeles, CA 90032 USA. Inst Sci Nucl, F-38026 Grenoble, France. Duke Univ, Durham, NC 27706 USA. Florida Int Univ, Miami, FL 33199 USA. Florida State Univ, Tallahassee, FL 32306 USA. Univ Georgia, Athens, GA 30602 USA. Hampton Univ, Hampton, VA 23668 USA. Harvard Univ, Cambridge, MA 02138 USA. Ist Nazl Fis Nucl, Sezione Bari, I-70126 Bari, Italy. Univ Bari, I-70126 Bari, Italy. Ist Nazl Fis Nucl, Sezione Lecce, I-73100 Lecce, Italy. Ist Nazl Fis Nucl, Sez Sanita, I-00161 Rome, Italy. Ist Super Sanita, Fis Lab, I-00161 Rome, Italy. Kent State Univ, Kent, OH 44242 USA. Univ Kentucky, Lexington, KY 40506 USA. Kharkov Phys & Technol Inst, UA-310108 Kharkov, Ukraine. Univ Maryland, College Pk, MD 20742 USA. Univ New Hampshire, Durham, NH 03824 USA. Norfolk State Univ, Norfolk, VA 23504 USA. N Carolina Cent Univ, Durham, NC 27707 USA. Old Dominion Univ, Norfolk, VA 23529 USA. Inst Phys Nucl, F-91406 Orsay, France. Princeton Univ, Princeton, NJ 08544 USA. Univ Regina, Regina, SK S4S 0A2, Canada. Rutgers State Univ, Piscataway, NJ 08854 USA. CEA Saclay, F-91191 Gif Sur Yvette, France. SUNY Stony Brook, Stony Brook, NY 11794 USA. Syracuse Univ, Syracuse, NY 13244 USA. Temple Univ, Philadelphia, PA 19122 USA. Thomas Jefferson Natl Accelerator Facil, Newport News, VA 23606 USA. Tohoku Univ, Sendai, Miyagi 980, Japan. Univ Virginia, Charlottesville, VA 22901 USA. Coll William & Mary, Williamsburg, VA 23187 USA. Yamagata Univ, Yamagata 990, Japan. Yerevan Phys Inst, Yerevan 375036, Armenia. RP Liyanage, N (reprint author), MIT, 77 Massachusetts Ave, Cambridge, MA 02139 USA. RI Perrino, Roberto/B-4633-2010; kino, koichi/D-6173-2012; Sarty, Adam/G-2948-2014; McIntyre, Justin/P-1346-2014; CAVATA, Christian/P-6496-2015; Cisbani, Evaristo/C-9249-2011; OI Perrino, Roberto/0000-0002-5764-7337; McIntyre, Justin/0000-0002-3706-4310; Cisbani, Evaristo/0000-0002-6774-8473; Glamazdin, Alexander/0000-0002-4172-7324 NR 34 TC 12 Z9 12 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD JUN 18 PY 2001 VL 86 IS 25 BP 5670 EP 5674 DI 10.1103/PhysRevLett.86.5670 PG 5 WC Physics, Multidisciplinary SC Physics GA 443ZG UT WOS:000169373000008 PM 11415329 ER PT J AU Yan, YF Zhang, SB Pantelides, ST AF Yan, YF Zhang, SB Pantelides, ST TI Control of doping by impurity chemical potentials: Predictions for p-type ZnO SO PHYSICAL REVIEW LETTERS LA English DT Article ID BAND-GAP SEMICONDUCTORS; DEFECTS; ZNSE AB Theoretical work has So far focused on the role of host-element chemical potentials in determining defect formation energies that control doping levels in semiconductors. Here, we report on our analysis of the role of the dopant-impurity chemical potential, which depends on the source gas. We present first-principles total-energy calculations that demonstrate a wide variation in the possible effective chemical potential of N. We account in detail for the recent puzzling observations of doping ZnO using N-2 and N2O and predict that the use of dilute NO or NO2 gas would resolve the long-standing problem of achieving p-type ZnO. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. Vanderbilt Univ, Dept Phys & Astron, Nashville, TN 37235 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Yan, YF (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. RI Krausnick, Jennifer/D-6291-2013; Zhang, Shengbai/D-4885-2013 OI Zhang, Shengbai/0000-0003-0833-5860 NR 11 TC 310 Z9 334 U1 6 U2 82 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 JUN 18 PY 2001 VL 86 IS 25 BP 5723 EP 5726 DI 10.1103/PhysRevLett.86.5723 PG 4 WC Physics, Multidisciplinary SC Physics GA 443ZG UT WOS:000169373000021 PM 11415342 ER PT J AU Cai, W Bulatov, VV Chang, JP Li, J Yip, S AF Cai, W Bulatov, VV Chang, JP Li, J Yip, S TI Anisotropic elastic interactions of a periodic dislocation array SO PHYSICAL REVIEW LETTERS LA English DT Article ID SILICON AB A method for calculating the anisotropic elastic energy of a dislocation dipole in a periodic cell is derived in which the infinite image summation is absolutely convergent. The core energy of a screw dislocation in Si, extracted from atomistic simulation, is shown to be manifestly system size invariant. Existence of special cell geometry where complete cancellation of elastic interactions occurs is demonstrated. C1 MIT, Dept Nucl Engn, Cambridge, MA 02139 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Cai, W (reprint author), MIT, Dept Nucl Engn, 77 Massachusetts Ave, Cambridge, MA 02139 USA. RI Li, Ju/A-2993-2008; OI Li, Ju/0000-0002-7841-8058; Cai, Wei/0000-0001-5919-8734 NR 8 TC 53 Z9 55 U1 0 U2 20 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 JUN 18 PY 2001 VL 86 IS 25 BP 5727 EP 5730 DI 10.1103/PhysRevLett.86.5727 PG 4 WC Physics, Multidisciplinary SC Physics GA 443ZG UT WOS:000169373000022 PM 11415343 ER PT J AU Boehler, R Ross, M Soderlind, P Boercker, DB AF Boehler, R Ross, M Soderlind, P Boercker, DB TI High-pressure melting curves of argon, krypton, and xenon: Deviation from corresponding states theory SO PHYSICAL REVIEW LETTERS LA English DT Article ID SOLID XENON; PHASE-TRANSITIONS; FIRST-PRINCIPLES; X-RAY; METALLIZATION; IRON AB The melting curves of argon, krypton, and xenon were measured in a laser heated diamond-anvil cell to pressures of nearly 80 GPa reaching melting temperatures around 3300 K. For the three gases, we observed a considerable decrease in the melting slopes (dT/dP) from the predictions based on corresponding states scaling starting near 40, 30, and 20 GPa, respectively. The melting anomaly can be understood in terms of a model in which hcp stacking faults act as solutes in a binary system. C1 Max Planck Inst Chem, D-55020 Mainz, Germany. Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Boehler, R (reprint author), Max Planck Inst Chem, Postfach 3060, D-55020 Mainz, Germany. NR 20 TC 83 Z9 83 U1 1 U2 22 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 JUN 18 PY 2001 VL 86 IS 25 BP 5731 EP 5734 DI 10.1103/PhysRevLett.86.5731 PG 4 WC Physics, Multidisciplinary SC Physics GA 443ZG UT WOS:000169373000023 PM 11415344 ER PT J AU Shibauchi, T Krusin-Elbaum, L Li, M Maley, MP Kes, PH AF Shibauchi, T Krusin-Elbaum, L Li, M Maley, MP Kes, PH TI Closing the pseudogap by Zeeman splitting in Bi2Sr2CaCu2O8+y at high magnetic fields SO PHYSICAL REVIEW LETTERS LA English DT Article ID INTERLAYER TUNNELING SPECTROSCOPY; HIGH-TEMPERATURE SUPERCONDUCTORS; SPIN-GAP; FERMI-SURFACE; FLUCTUATIONS; DEPENDENCE; STATE AB Interlayer tunneling resistivity is used to probe the low-energy density-of-states (DOS) depletion due to the pseudogap in the normal state of Bi(2)Sr(2)CaCU(2)Q(8+y) Measurements up to 60 T reveal that a field that restores DOS to its ungapped state shows strikingly different temperature and doping dependencies from the characteristic fields of the superconducting state. The pseudogap closing field and the pseudogap temperature T* evaluated independently are related through a simple Zeeman energy scaling. These. findings indicate a predominant role of spins over the orbital effects in the formation of the pseudogap. C1 IBM Corp, Thomas J Watson Res Ctr, Yorktown Heights, NY 10598 USA. Univ Calif Los Alamos Natl Lab, Superconduct Technol Ctr, Los Alamos, NM 87545 USA. Leiden Univ, Kamerlingh Onnes Lab, NL-2300 RA Leiden, Netherlands. RP Shibauchi, T (reprint author), IBM Corp, Thomas J Watson Res Ctr, Yorktown Heights, NY 10598 USA. RI Shibauchi, Takasada/B-9349-2008 OI Shibauchi, Takasada/0000-0001-5831-4924 NR 33 TC 111 Z9 111 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 JUN 18 PY 2001 VL 86 IS 25 BP 5763 EP 5766 DI 10.1103/PhysRevLett.86.5763 PG 4 WC Physics, Multidisciplinary SC Physics GA 443ZG UT WOS:000169373000031 PM 11415352 ER PT J AU Knill, E Laflamme, R Martinez, R Negrevergne, C AF Knill, E Laflamme, R Martinez, R Negrevergne, C TI Benchmarking quantum computers: The five-qubit error correcting code SO PHYSICAL REVIEW LETTERS LA English DT Article ID EXPERIMENTAL REALIZATION; ENTANGLEMENT AB The smallest quantum code that can correct all one-qubit errors is based on five qubits. We experimentally implemented the encoding, decoding, and error-correction quantum networks using nuclear magnetic resonance on a five spin subsystem of labeled crotonic acid. The ability to correct each error was verified by tomography of the process. The use of error correction for benchmarking quantum networks is discussed, and we infer that the fidelity achieved in our experiment is sufficient for preserving entanglement. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Knill, E (reprint author), Univ Calif Los Alamos Natl Lab, MS B265, Los Alamos, NM 87545 USA. NR 18 TC 102 Z9 104 U1 0 U2 5 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD JUN 18 PY 2001 VL 86 IS 25 BP 5811 EP 5814 DI 10.1103/PhysRevLett.86.5811 PG 4 WC Physics, Multidisciplinary SC Physics GA 443ZG UT WOS:000169373000043 PM 11415364 ER PT J AU Stocking, EM Sanz-Cervera, JF Unkefer, CJ Williams, RM AF Stocking, EM Sanz-Cervera, JF Unkefer, CJ Williams, RM TI Studies on the biosynthesis of paraherquamide. Construction of the amino acid framework SO TETRAHEDRON LA English DT Article DE biosynthesis; secondary metabolism; feeding experiments ID DIELS-ALDER CYCLOADDITION; VM55599 RING-SYSTEMS; ANTHELMINTIC ACTIVITY; L-PROLINE; PENICILLIUM-CHARLESII; ANTIPARASITIC AGENTS; PRENYL TRANSFERASES; BETA-METHYLPROLINE; BREVIANAMIDE-B; SCLEROTAMIDE AB It has been previously established in this laboratory that the beta -methyl-beta -hydroxyproline moiety of the potent anthelmintic agent paraherquamide A, is biosynthetically derived from L-isoleucine. The downstream events from L-Ile to paraherquamide A have now been investigated. The synthesis of [1-(13)C]-labeled L-beta -methylproline is described by means of a Hoffman-Loeffler-Freytag reaction sequence from [1-(13)C]-L-Ile. This amino acid is shown to be a direct biosynthetic precursor to paraherquamide A by feeding and incorporation experiments in growing cultures of Penicillum fellutanum. Three tryptophan-containing dipeptides of L-beta -methylproline have been constructed: [(13)C(2)]-2-(l,1-dimethyl-2-propenyl)-L-tryptophanyl-3(S)-methyl-L-proline [(13)C(2)]-3(S)-methyl-L-prolyl-2-(l,1-dimethyl-2-propenyl)-L-tryptophan and [(13)C(2)]-cyclo-2-(l,1-dimethyl-2-propenyl)-L-tryptophan-3(S)-methyl-L-proline. [alpha-(15)N, 1-(13)C]-2-(1,1-Dimethyl-2-propenyl)-L-tryptophan was also prepared but none of these substances were found to serve as biosynthetic precursors to paraherquamide A. (C) 2001 Elsevier Science Ltd. All rights reserved. C1 Colorado State Univ, Dept Chem, Ft Collins, CO 80523 USA. Univ Valencia, Dept Quim Inorgan, E-46100 Valencia, Spain. Los Alamos Natl Lab, NIH, Stable Isotope Resource, Los Alamos, NM 87545 USA. RP Williams, RM (reprint author), Colorado State Univ, Dept Chem, Ft Collins, CO 80523 USA. EM rmw@chem.colostate.edu RI Sanz-Cervera, Juan/K-1095-2014 NR 34 TC 23 Z9 24 U1 0 U2 7 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0040-4020 J9 TETRAHEDRON JI Tetrahedron PD JUN 18 PY 2001 VL 57 IS 25 BP 5303 EP 5320 DI 10.1016/S0040-4020(01)00449-5 PG 18 WC Chemistry, Organic SC Chemistry GA 445DP UT WOS:000169443100002 ER PT J AU Holben, BN Tanre, D Smirnov, A Eck, TF Slutsker, I Abuhassan, N Newcomb, WW Schafer, JS Chatenet, B Lavenu, F Kaufman, YJ Castle, JV Setzer, A Markham, B Clark, D Frouin, R Halthore, R Karneli, A O'Neill, NT Pietras, C Pinker, RT Voss, K Zibordi, G AF Holben, BN Tanre, D Smirnov, A Eck, TF Slutsker, I Abuhassan, N Newcomb, WW Schafer, JS Chatenet, B Lavenu, F Kaufman, YJ Castle, JV Setzer, A Markham, B Clark, D Frouin, R Halthore, R Karneli, A O'Neill, NT Pietras, C Pinker, RT Voss, K Zibordi, G TI An emerging ground-based aerosol climatology: Aerosol optical depth from AERONET SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID NORTHEASTERN TROPICAL ATLANTIC; LONG-RANGE TRANSPORT; MAUNA-LOA; ATMOSPHERIC TURBIDITY; STRATOSPHERIC AEROSOL; PRECIPITABLE WATER; SOUTHERN AFRICA; DESERT AEROSOL; DUST; NORTH AB Long-term measurements by the AERONET program of spectral aerosol optical depth, precipitable water, and derived Angstrom exponent were analyzed and compiled into an aerosol optical properties climatology. Quality assured monthly means are presented and described for 9 primary sites and 21 additional multiyear sites with distinct aerosol regimes representing tropical biomass burning, boreal forests, midlatitude humid climates, midlatitude dry climates, oceanic sites, desert sites, and background sites. Seasonal trends for each of these nine sites are discussed and climatic averages presented. C1 NASA, Goddard Space Flight Ctr, Biospher Sci Branch, Greenbelt, MD 20771 USA. Univ Lille 1, Ctr Hyperfrequences & Semicond, CNRS, Opt Atmospher Lab, F-59655 Villeneuve Dascq, France. Sci Syst & Applicat Inc, Lanham, MD 20706 USA. Raytheon STX Corp, Lanham, MD USA. Univ Paris 07, Lab Interuniv Syst Atmospher, F-94010 Creteil, France. Univ Paris 12, F-94010 Creteil, France. CNRS, CESBIO, Toulouse, France. NASA, Goddard Space Flight Ctr, Climate & Radiat Branch, Greenbelt, MD 20771 USA. Univ New Mexico, Albuquerque, NM 87106 USA. Inst Pesquisas Espaciais, Sao Jose Dos Campos, San Paolo, Brazil. NOAA, Silver Spring, MD 20746 USA. Scripps Inst Oceanog, La Jolla, CA 92093 USA. Brookhaven Natl Lab, Dept Appl Sci, Upton, NY 11973 USA. Ben Gurion Univ Negev, IL-84990 Sede Boqer, Israel. Univ Sherbrooke, CARTEL, Sherbrooke, PQ J1K 2R1, Canada. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. SAIC, GSC, Beltsville, MD USA. Univ Maryland, Dept Meteorol, College Pk, MD 20742 USA. Univ Miami, Dept Phys, Miami, FL 33124 USA. Commiss European Communities, Joint Res Ctr, Space Applicat Inst, I-21020 Ispra, Italy. RP Holben, BN (reprint author), NASA, Goddard Space Flight Ctr, Biospher Sci Branch, Code 923, Greenbelt, MD 20771 USA. RI Pinker, Rachel/F-6565-2010; Schafer, Joel/A-3978-2010; Smirnov, Alexander/C-2121-2009; ECK, THOMAS/D-7407-2012; Voss, Kenneth /A-5328-2013; Markham, Brian/M-4842-2013 OI Smirnov, Alexander/0000-0002-8208-1304; Voss, Kenneth /0000-0002-7860-5080; Markham, Brian/0000-0002-9612-8169 NR 77 TC 966 Z9 999 U1 8 U2 73 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0747-7309 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD JUN 16 PY 2001 VL 106 IS D11 BP 12067 EP 12097 DI 10.1029/2001JD900014 PG 31 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 442TC UT WOS:000169300200027 ER PT J AU Michalsky, JJ Schlemmer, FA Berkheiser, WE Berndt, JL Harrison, LC Laulainen, NS Larson, NR Barnard, JC AF Michalsky, JJ Schlemmer, FA Berkheiser, WE Berndt, JL Harrison, LC Laulainen, NS Larson, NR Barnard, JC TI Multiyear measurements of aerosol optical depth in the Atmospheric Radiation Measurement and Quantitative Links programs SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID WATER-VAPOR; RADIOMETERS; IRRADIANCE; SCATTERING AB The U.S. Department of Energy funded the development of the multifilter rotating shadowband radiometer (MFRSR) as part of the Atmospheric Radiation Measurement (ARM) program. This seven-channel radiometer began operation at the first ARM site in 1992 and at the Department of Energy Quantitative Links (QL) sites in the fall of 1991; three of the QL sites continue to operate, although this program was discontinued after 1995. This paper describes the use of the MFRSR in acquiring aerosol optical depth data, including the in-field calibration procedure and a partial validation of this process. Multiyear measurements of aerosol optical depth from three of the sites indicate similar phasing of seasonal and interannual changes, but with notable differences in the magnitude of the aerosol optical depth. Published papers that use these aerosol data are highlighted, and public access to these and future data sets for scientific studies are explained. C1 SUNY Albany, Atmospher Sci Res Ctr, Albany, NY 12203 USA. Pacific NW Natl Lab, Richland, WA 99352 USA. RP Michalsky, JJ (reprint author), SUNY Albany, Atmospher Sci Res Ctr, 251 Fuller Rd, Albany, NY 12203 USA. NR 28 TC 79 Z9 80 U1 0 U2 7 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0747-7309 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD JUN 16 PY 2001 VL 106 IS D11 BP 12099 EP 12107 DI 10.1029/2001JD900096 PG 9 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 442TC UT WOS:000169300200028 ER PT J AU Michelsen, HA AF Michelsen, HA TI Carbon and hydrogen kinetic isotope effects for the reaction of Cl with CH4: Consolidating chemical kinetics and molecular dynamics measurements SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID LOWER ANTARCTIC STRATOSPHERE; DIFFERENTIAL CROSS-SECTIONS; POTENTIAL-ENERGY SURFACE; TRANSITION-STATE REGION; LARGE (CO)-C-13 DEFICIT; OZONE HOLE CHEMISTRY; ATMOSPHERIC CH4; CHLORINE ATOMS; METHANE; SPECTROSCOPY AB In order to estimate carbon and hydrogen kinetic isotope effects for the reaction Cl+ CH, at atmospheric temperatures, measured values of the rates of Cl reacting with (CH4)-C-13, (CH3D)-C-12, (CH2D2)-C-12, (CHD3)-C-12, and (CD4)-C-12 relative to those of Cl+(CH4)-C-12 were fit using a model that accounts for quantum mechanical tunneling. The model also includes vibrational enhancement of the reaction rate by excitation of the bending and stretching modes of CH,. These fits allow extrapolation of measured values to temperatures outside the range in which they were measured. In addition, the kinetic isotope effect for Cl+(CH4)-C-14 was predicted using this model based on the results for Cl+ (CH4)-C-13. The model results for Cl+(CH4)-C-14, Cl+(CH4)-C-13, and Cl+(CH3D)-C-12 were parameterized for use in atmospheric models. C1 Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA. RP Michelsen, HA (reprint author), Sandia Natl Labs, Combust Res Facil, MS 9055,POB 969, Livermore, CA 94551 USA. NR 50 TC 6 Z9 6 U1 0 U2 8 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0747-7309 J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD JUN 16 PY 2001 VL 106 IS D11 BP 12267 EP 12274 DI 10.1029/2000JD900689 PG 8 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 442TC UT WOS:000169300200041 ER PT J AU Ginocchio, JN AF Ginocchio, JN TI A relativistic symmetry in nuclei: Its origins and consequences SO NUCLEAR PHYSICS A LA English DT Article; Proceedings Paper CT International Symposium on Nuclei and Nucleons CY OCT 11-13, 2000 CL DARMSTADT UNIV TECH, LICHTENBERG BLDG, DARMSTADT, GERMANY SP Deutsch Forsch Gameinsch, Gesell Schwerionen Forsch, Bruker Analytik GmbH, Compaq Comp GmbH, HEAG AG, ISEG Spezialelektronik GmbH, Scionix Holland BV, Siemens AG, Wissenschaftsstadt Darmstadt, Off Mayor HO DARMSTADT UNIV TECH, LICHTENBERG BLDG ID PSEUDOSPIN SYMMETRY; ELASTIC-SCATTERING; FIELD THEORY; POTENTIALS; MODEL; ALIGNMENT; PB-208 C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Ginocchio, JN (reprint author), Univ Calif Los Alamos Natl Lab, MS B283, Los Alamos, NM 87545 USA. NR 40 TC 2 Z9 2 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 JUN 16 PY 2001 VL 690 IS 1-3 BP 41C EP 51C PG 11 WC Physics, Nuclear SC Physics GA 447UP UT WOS:000169591100005 ER PT J AU Lipschutz, ME Wolf, SF Hanchar, JM Culp, FB AF Lipschutz, ME Wolf, SF Hanchar, JM Culp, FB TI Geochemical and cosmochemical materials SO ANALYTICAL CHEMISTRY LA English DT Review ID PLASMA-MASS SPECTROMETRY; RARE-EARTH ELEMENTS; GEOLOGICAL REFERENCE MATERIALS; PLATINUM-GROUP ELEMENTS; SECTOR ICP-MS; SPINEL PERIDOTITE XENOLITHS; EARLY SOLAR-SYSTEM; ISOTOPE-DILUTION; TRACE-ELEMENTS; PRECISE DETERMINATION C1 Purdue Univ, Dept Chem, W Lafayette, IN 47907 USA. Argonne Natl Lab, Argonne, IL 60439 USA. George Washington Univ, Dept Earth & Environm Sci, Washington, DC 20006 USA. RP Lipschutz, ME (reprint author), Purdue Univ, Dept Chem, BRWN WTHR Bldg, W Lafayette, IN 47907 USA. NR 126 TC 13 Z9 14 U1 0 U2 4 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 JUN 15 PY 2001 VL 73 IS 12 BP 2687 EP 2699 DI 10.1021/ac010280g PG 13 WC Chemistry, Analytical SC Chemistry GA 443HP UT WOS:000169336000001 PM 11432697 ER PT J AU Workman, J Creasy, KE Doherty, S Bond, L Koch, M Ullman, A Veltkamp, DJ AF Workman, J Creasy, KE Doherty, S Bond, L Koch, M Ullman, A Veltkamp, DJ TI Process analytical chemistry SO ANALYTICAL CHEMISTRY LA English DT Review ID REAL-TIME MEASUREMENT; MASS-SPECTROMETRY; CAPILLARY-ELECTROPHORESIS; REGRESSION-MODELS; CHEMICAL-ANALYSIS; SYSTEM; SPECTROSCOPY; ULTRASOUND; CHEMOMETRICS; CALIBRATION C1 Kimberly Clark Inc, Analyt Sci & Technol, Neenah, WI 54956 USA. Honeywell Labs, Proc Analyt Chem Ctr, Morristown, NJ 07962 USA. Monsanto Co, Chem Sci Grp, Skokie, IL 60077 USA. Pacific NW Natl Lab, Richland, WA 99352 USA. Univ Washington, Ctr Proc Analyt Chem, Seattle, WA 98195 USA. Procter & Gamble Co, Cincinnati, OH 43224 USA. RP Workman, J (reprint author), Kimberly Clark Inc, Analyt Sci & Technol, Neenah, WI 54956 USA. NR 115 TC 49 Z9 50 U1 3 U2 18 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 JUN 15 PY 2001 VL 73 IS 12 BP 2705 EP 2718 DI 10.1021/ac010364p PG 14 WC Chemistry, Analytical SC Chemistry GA 443HP UT WOS:000169336000003 PM 11432699 ER PT J AU Durakiewicz, T Halas, S AF Durakiewicz, T Halas, S TI Calculation of ionization potential of small yttrium and lanthanide metal clusters SO CHEMICAL PHYSICS LETTERS LA English DT Article ID THRESHOLD PHOTOIONIZATION; WORK FUNCTION; SIZE; ELEMENTS AB Our analytic formula for ionization potential (IP) of a metal cluster of given radius, R, is adapted to small size clusters with number of atoms n < 40. The radius is defined as the distance between gravity center and the most remote atom surface. R was either calculated or determined experimentally with relative uncertainty of 3%. We have found that R(n) significantly fluctuates around 1.30 n(1/3) for n < 40. The calculated IP values for Y-n and Ce-n small clusters indicate the valence transition from Z = 3 to Z = 2 at n = 6 and 3, respectively, whereas Z = 3 may be considered for Pr-5 and perhaps for Pr-6 <(c)> 2001 Published by Elsevier Science B.V. C1 Univ Calif Los Alamos Natl Lab, Grp MST10, Los Alamos, NM 87545 USA. Marie Curie Sklodowska Univ, Inst Phys, Mass Spectrometry Lab, PL-20031 Lublin, Poland. Inst Vacuum Technol, PL-00241 Warsaw, Poland. RP Durakiewicz, T (reprint author), Univ Calif Los Alamos Natl Lab, Grp MST10, Mailstop K764, Los Alamos, NM 87545 USA. OI Durakiewicz, Tomasz/0000-0002-1980-1874 NR 13 TC 19 Z9 19 U1 0 U2 4 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 JUN 15 PY 2001 VL 341 IS 1-2 BP 195 EP 200 DI 10.1016/S0009-2614(01)00459-6 PG 6 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 445QE UT WOS:000169468100027 ER PT J AU Bauerdick, LAT Fox-Murphy, A Haas, T Stonjek, S Tassi, E AF Bauerdick, LAT Fox-Murphy, A Haas, T Stonjek, S Tassi, E TI Event indexing systems for efficient selection and analysis of HERA data SO COMPUTER PHYSICS COMMUNICATIONS LA English DT Article DE computer data analysis; data management AB The design and implementation of two software systems introduced to improve the efficiency of offline analysis of event data taken with the ZEUS Detector at the HERA electron-proton collider at DESY are presented. Two different approaches were made, one using a set of event directories and the other using a tag database based on a commercial object-oriented database management system. These are described and compared. Both systems provide quick direct access to individual collision events in a sequential data store of several terabytes, and they both considerably improve the event analysis efficiency. In particular the tag database provides a very flexible selection mechanism and can dramatically reduce the computing time needed to extract small subsamples from the total event sample of the experiment. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Deutsch Elektronensynchrotron, D-22603 Hamburg, Germany. RP Haas, T (reprint author), Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RI Tassi, Enrico/K-3958-2015 NR 11 TC 1 Z9 1 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0010-4655 J9 COMPUT PHYS COMMUN JI Comput. Phys. Commun. PD JUN 15 PY 2001 VL 137 IS 2 BP 236 EP 246 DI 10.1016/S0010-4655(01)00162-X PG 11 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA 444XF UT WOS:000169424800002 ER PT J AU Liu, CX Kota, S Zachara, JM Fredrickson, JK Brinkman, CK AF Liu, CX Kota, S Zachara, JM Fredrickson, JK Brinkman, CK TI Kinetic analysis of the bacterial reduction of goethite SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Article ID CRYSTALLINE IRON(III) OXIDES; PARTICLE CONCENTRATION; REACTIVE TRANSPORT; DISSIMILATORY REDUCTION; MICROBIAL REDUCTION; TEXAS ESTUARIES; FE(III) OXIDE; FERROUS IRON; BAY ESTUARY; SURFACE AB The kinetics of dissimilatory reduction of goethite (alpha -FeOOH) was studied in batch cultures of a groundwater bacterium, Shewanella putrefaciens, strain CN32 in pH 7 bicarbonate buffer. The rate and extent of goethite reduction were measured as a function of electron acceptor (goethite) and donor (lactate) concentrations. Increasing goethite concentrations increased both the rate and extent of Fe(lll) reduction when cell and lactate concentrations were held constant. However, constant initial reduction rates were observed after normalization to the Fe(ll) sorption capacity of FeOOH, suggesting that the bacterial reduction rate was first order with respect to surface site concentration. Increasing the lactate concentration also increased the rate and extent of FeOOH reduction. Monod-type kinetic behavior was observed with respect to lactate concentration. Fe(ll) sorption on FeOOH was well-described by the Langmuir sorption isotherm. However, the Fe(ll) sorption capacities hyperbolically decreased with increasing FeOOH concentration (10-100 mM) implying aggregation, while the affinity constant between Fe(ll)and goethite was constant (log K approximate to 3). Evaluation of the end states of the variable FeOOH and lactate experiments when iron reduction ceased indicated a consistent excess in reaction free energy of -22.7 kJ/mol. This value was remarkably close to the minimum value reported for bacteria to mediate a given reaction (-20 kJ/mol). X-ray diffraction (XRD) and scanning electron microscopy (SEM) indicated that siderite (FeCO3) was the only biogenic Fe(ll) solid formed upon Fe00H bioreduction. A kinetic biogeochemical model that incorporated Monod kinetics with respect to lactate concentration, first-order kinetics with respect to goethite surface concentration, a Gibbs free energy availability factor, the rates of Fe(ll) sorption on goethite and siderite precipitation, and aqueous speciation reactions was applied to the experimental data. Using independently estimated parameters, the developed model successfully described bacterial goethite reduction with variable FeOOH and lactate concentrations. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Liu, CX (reprint author), Pacific NW Natl Lab, POB 999,MS K8-96, Richland, WA 99352 USA. EM chongxuan.liu@pnl.gov RI Liu, Chongxuan/C-5580-2009; OI Liu, Chongxuan/0000-0002-2180-6770 NR 71 TC 117 Z9 131 U1 6 U2 64 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0013-936X EI 1520-5851 J9 ENVIRON SCI TECHNOL JI Environ. Sci. Technol. PD JUN 15 PY 2001 VL 35 IS 12 BP 2482 EP 2490 DI 10.1021/es001956c PG 9 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 443LY UT WOS:000169343700013 PM 11432552 ER PT J AU King, JK Kostka, JE Frischer, ME Saunders, FM Jahnke, RA AF King, JK Kostka, JE Frischer, ME Saunders, FM Jahnke, RA TI A quantitative relationship that remonstrates mercury methylation rates in marine sediments are based on the community composition and activity of sulfate-reducing bacteria SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Article ID TARGETED OLIGONUCLEOTIDE PROBES; SALT-MARSH SEDIMENT; RIBOSOMAL-RNA; SPARTINA-ALTERNIFLORA; PORE WATERS; SPECIATION; REDUCTION; ESTUARY; BIOAVAILABILITY; HYBRIDIZATION AB A quantitative framework was developed which estimates mercury methylation rates (MMR) in sediment cores based on measured sulfate reduction rates (SRR) and the community composition sulfate-reducing bacterial consortia. MMR and SRR as well as group-specific 16S rRNA concentrations (as quantified by probe signal) associated with sulfate-reducing bacteria (SRB) were measured in triplicate cores of saltmarsh sediments. Utilizing previously documented conversion factors in conjunction with field observations of sulfate reduction, MMR were calculated, and the results were compared to experimentally derived measurements of MMR. Using our novel field data collected in saltmarsh sediment where sulfate reduction activity is high, calculated and independently measured MMR results were consistently within an order of magnitude and displayed similar trends with sediment depth. In an estuarine sediment where sulfate reduction activity was low, calculated and observed MMR diverged by greater than an order of magnitude, but again trends with depth were similar. We have expanded the small database generated to date on mercury methylation in sulfur-rich marine sediments. The quantitative framework we have developed further elucidates the coupling of mercury methylation to sulfate reduction by basing calculated rates of mercury methylation on the activity and community composition of sulfate-reducing bacteria. The quantitative framework may also provide a promising alternative to the difficult and hazardous determination of MMR using radiolabeled mercury. C1 Skidaway Inst Oceanog, Savannah, GA 31411 USA. Westinghouse Savannah River Co, Savannah River Lab, Aiken, SC 29808 USA. Florida State Univ, Dept Oceanog, Tallahassee, FL 32306 USA. Georgia Inst Technol, Sch Civil & Environm Engn, Atlanta, GA 30332 USA. RP King, JK (reprint author), Skidaway Inst Oceanog, POB 13687, Savannah, GA 31411 USA. RI Mason, Robert/A-6829-2011; Frischer, Marc/L-5207-2014 NR 35 TC 113 Z9 123 U1 6 U2 43 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 JUN 15 PY 2001 VL 35 IS 12 BP 2491 EP 2496 DI 10.1021/es001813q PG 6 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 443LY UT WOS:000169343700014 PM 11432553 ER PT J AU Gamerdinger, AP Kaplan, DI AF Gamerdinger, AP Kaplan, DI TI Physical and chemical determinants of colloid transport and deposition in water-unsaturated sand and Yucca Mountain tuff material SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Article ID POROUS-MEDIA; SOLUTE TRANSPORT; IONIC-STRENGTH; PARTICLES; MODEL AB Colloid mobility was determined in a system consisting of quartz sand or crushed Yucca Mountain tuff, simulated groundwater (J-13), and hydrophilic latex particles. Water content (theta) and ionic strength (l; Dl water, 0.1 x, Ix, 10x groundwater dilution) were manipulated to define limiting conditions for colloid transport at the Yucca Mountain site. Colloid transport, measured with a centrifuge method at relatively high theta (saturation > 36% for sand, > 62% for crushed tuff) in D1 water, was equivalent to transport at 100% saturation measured with conventional columns. When variables were isolated, increasing I and decreasing theta resulted in a greater extent of colloid deposition; I was more important at higher theta; physical properties were more important at lower theta. l and theta had an interactive effect on colloid deposition whereby synergism was generally observed, especially for simulated groundwater (1x); antagonism was observed at 10x groundwater dilution. At 19% moisture saturation on the crushed tuff, a decreasing rate of colloid deposition was observed. This corresponded to a hydrodynamic condition of 79% immobile water where solute tracers were excluded from a fraction of the pore volume. This suggests that a portion of the favorable sites for deposition were associated with the excluded or immobile water domain and were not accessible to colloids. C1 Washington State Univ, Dept Chem, Richland, WA 99352 USA. Washington State Univ, Ctr Multiphase Environm Res, Richland, WA 99352 USA. Pacific NW Natl Lab, Richland, WA 99352 USA. Westinghouse Savannah River Co, Savannah River Technol Ctr, Aiken, SC 29808 USA. RP Gamerdinger, AP (reprint author), Washington State Univ, Dept Chem, Richland, WA 99352 USA. NR 27 TC 34 Z9 37 U1 2 U2 15 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 JUN 15 PY 2001 VL 35 IS 12 BP 2497 EP 2504 DI 10.1021/es001434x PG 8 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 443LY UT WOS:000169343700015 PM 11432554 ER PT J AU Siegel, RW Jain, R Bradbury, A AF Siegel, RW Jain, R Bradbury, A TI Using an in vivo phagemid system to identify non-compatible loxP sequences SO FEBS LETTERS LA English DT Article DE Cre; LoxP; recombination; phagemid; functional genomics ID SITE-SPECIFIC RECOMBINATION; CRE-MEDIATED RECOMBINATION; AFFINITY HUMAN-ANTIBODIES; MAMMALIAN-CELLS; TRANSGENIC MICE; SPACER REGION; DNA; REPLACEMENT; INTEGRATION; ACTIVATION AB The site-specific recombination system of bacteriophage P1 is composed of the Cre recombinase that recognizes a 34-bp loxP site. The CrelloxP system has been extensively used to manipulate eukaryotic genomes for functional genomic investigations, The creation of additional heterologous loxP sequences potentially expands the utility of this system, but only if these loxP sequences do not recombine with one another. We have developed a stringent in,vivo assay to examine the degree of recombination between all combinations of each previously published heterologous loxP sequence, As expected, homologous loxP sequences efficiently underwent Cre-mediated recombination, However, many of the heterologous loxP pairs were able to support recombination with rates varying from 5 to 100%. Some of these loxP sequences have previously been reported to be noncompatible with one another, Our study also confirmed other heterologous loxP pairs that had previously been shown to be non-compatible, as well as defined additional combinations that could be used in designing new recombination vectors, (C) 2001 Federation of European Biochemical Societies, Published by Elsevier Science B.V. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Biosci Div, Los Alamos, NM 87545 USA. SISSA, I-34014 Trieste, Italy. RP Bradbury, A (reprint author), Univ Calif Los Alamos Natl Lab, Biosci Div, MS-M888, Los Alamos, NM 87545 USA. OI Siegel, Robert/0000-0002-0833-5580 NR 24 TC 18 Z9 21 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0014-5793 J9 FEBS LETT JI FEBS Lett. PD JUN 15 PY 2001 VL 499 IS 1-2 BP 147 EP 153 DI 10.1016/S0014-5793(01)02541-8 PG 7 WC Biochemistry & Molecular Biology; Biophysics; Cell Biology SC Biochemistry & Molecular Biology; Biophysics; Cell Biology GA 447BR UT WOS:000169549100031 PM 11418130 ER PT J AU Lueker, TJ Keeling, RF Dubey, MK AF Lueker, TJ Keeling, RF Dubey, MK TI The oxygen to carbon dioxide ratios observed in emissions from a wildfire in Northern California SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID TRANSFORM INFRARED-SPECTROSCOPY; BIOMASS FIRES; TRACE GASES AB At Trinidad, California we observed elevated CO2 concentrations and concomitant lowered O-2 levels coincident with forest fires 70 kin distant (from 10/8/99 to 10/21/99). The precision of our O-2 data, 1 mu mol O-2 /mol dry air, revealed the reduction of atmospheric oxygen resulting from the combustion of biomass, and the stoichiometric ratios (-O-2/CO2) of the wildfire emissions. Estimates of daily -O-2/CO2 ratios were obtained by regression of CO2 against corresponding O-2 data (R-2, 0.86 to 0.96). Daily -O-2/CO2 ratios changed from 1.15 to 1.41 on a particularly smoky day that coincided with elevated levels of CH4 and increased CH4/CO2 ratios. The change to a higher ratio during smoky conditions illustrates the association between changing emissions and -O-2/CO2 ratios, possibly due to changing wildfire dynamics. C1 Univ Calif San Diego, Scripps Inst Oceanog, La Jolla, CA 92093 USA. Los Alamos Natl Lab, Los Angeles, CA USA. RP Lueker, TJ (reprint author), Univ Calif San Diego, Scripps Inst Oceanog, La Jolla, CA 92093 USA. RI Dubey, Manvendra/E-3949-2010 OI Dubey, Manvendra/0000-0002-3492-790X NR 20 TC 7 Z9 7 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 JUN 15 PY 2001 VL 28 IS 12 BP 2413 EP 2416 DI 10.1029/2000GL011860 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 472WT UT WOS:000171008500031 ER PT J AU Lehoucq, RB Salinger, AG AF Lehoucq, RB Salinger, AG TI Large-scale eigenvalue calculations for stability analysis of steady flows on massively parallel computers SO INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN FLUIDS LA English DT Article ID VAPOR-DEPOSITION REACTOR; HEAT-TRANSFER; FLUID-FLOW; EQUATIONS AB This paper presents an approach for determining the linear stability of steady states of partial differential equations (PDEs) on massively parallel computers. Linearizing the transient behavior around a steady state solution leads to an eigenvalue problem. The eigenvalues with the largest real part are calculated using Arnoldi's iteration driven by a novel implementation of the Cayley transformation. The Cayley transformation requires the solution of a linear system at each Arnoldi iteration. This is done iteratively so that the algorithm scales with problem size. A representative model problem of three-dimensional incompressible flow and heat transfer in a rotating disk reactor is used to analyze the effect of algorithmic parameters on the performance of the eigenvalue algorithm. Successful calculations of leading eigenvalues for matrix systems of order up to 4 million were performed, identifying the critical Grashof number for a Hopf bifurcation. Copyright (C) 2001 John Wiley & Sons, Ltd. C1 Sandia Natl Labs, Appl & Numerical Math Dept, Albuquerque, NM 87185 USA. Sandia Natl Labs, Parallel Computat Sci Dept, Albuquerque, NM 87185 USA. RP Salinger, AG (reprint author), Sandia Natl Labs, Appl & Numerical Math Dept, MS 1110,POB 5800, Albuquerque, NM 87185 USA. NR 26 TC 35 Z9 35 U1 1 U2 4 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 0271-2091 J9 INT J NUMER METH FL JI Int. J. Numer. Methods Fluids PD JUN 15 PY 2001 VL 36 IS 3 BP 309 EP 327 PG 19 WC Computer Science, Interdisciplinary Applications; Mathematics, Interdisciplinary Applications; Mechanics; Physics, Fluids & Plasmas SC Computer Science; Mathematics; Mechanics; Physics GA 439PN UT WOS:000169126400004 ER PT J AU Anders, A Yotsombat, B Binder, R AF Anders, A Yotsombat, B Binder, R TI Correlation between cathode properties, burning voltage, and plasma parameters of vacuum arcs SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID CHARGE-STATE DISTRIBUTIONS AB Burning voltages of vacuum arcs were measured for 54 cathode materials and compared with literature data. As anticipated, a correlation between the arc burning voltage and the plasma temperature was found. However, more importantly, a correlation between the cohesive energy of the cathode material and the arc burning voltage could be demonstrated. This link between a cathode material property, the cohesive energy, and a discharge property, the arc burning voltage, is essential for the operation of the vacuum arc discharge because is determines the plasma temperature. Energy balance considerations show that this "cohesive energy rule" is responsible for several other secondary relationships, such as the correlation between the mean ion charge state and the boiling temperature of the cathode. (C) 2001 American Institute of Physics. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Chiang Mai Univ, Dept Phys, Chiang Mai 50200, Thailand. Alameda Appl Sci Corp, San Leandro, CA 94577 USA. RP Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. EM aanders@lbl.gov RI Anders, Andre/B-8580-2009 OI Anders, Andre/0000-0002-5313-6505 NR 21 TC 47 Z9 47 U1 0 U2 7 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 JUN 15 PY 2001 VL 89 IS 12 BP 7764 EP 7771 DI 10.1063/1.1371276 PG 8 WC Physics, Applied SC Physics GA 440PM UT WOS:000169183500011 ER PT J AU Kai, T Fujiwara, H Schulthess, TC Butler, WH AF Kai, T Fujiwara, H Schulthess, TC Butler, WH TI First principles study of direct exchange coupling between the grains in NiMn antiferromagnets SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID FILMS AB Exchange coupling between antiferromagnetic regions of tetragonal NiMn through a separation at a boundary was evaluated by first principles calculation to study the coupling between antiferromagnetic grains. It was assumed that the crystallographic orientation was assumed not to change across the boundary. The layer version of the Korringa-Kohn-Rostoker method was employed to calculate the total energy of the coupled system. The exchange coupling strength was estimated as the total energy difference between the two spin configurations of the two body system, parallel and antiparallel to each other. For the grains without any atomic lattice shift parallel to the plane (100) across the boundary, it was found that the coupling strength decreases more rapidly than that for ferromagnetic hexagonal cobalt with the increase of the separation and that it changes its sign at a separation length of a little greater than a half of the lattice constant. For the case with a boundary across which the lattice shifts by an atomic distance diagonally, the exchange coupling is reduced to about 1/3 of the original value and decreases rather slowly with the increase of the separation compared to the previous case. Those results are consistent with our previous report which predicted the existence of a weak exchange coupling between the grains in an antiferromagnetic polycrystalline layer based on the analysis of a characteristic feature often observed in torque curves for ferro/antiferromagnetic coupled layer systems. (C) 2001 American Institute of Physics. C1 Univ Alabama, MINT Ctr, Tuscaloosa, AL 35487 USA. Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Kai, T (reprint author), Toshiba Corp, Ctr Res & Dev, Kawasaki, Kanagawa 2128582, Japan. NR 9 TC 2 Z9 2 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD JUN 15 PY 2001 VL 89 IS 12 BP 7940 EP 7942 DI 10.1063/1.1371945 PG 3 WC Physics, Applied SC Physics GA 440PM UT WOS:000169183500039 ER PT J AU Gruber, JB Zandi, B Lozykowski, HJ Jadwisienczak, WM Brown, I AF Gruber, JB Zandi, B Lozykowski, HJ Jadwisienczak, WM Brown, I TI Crystal-field splitting of Pr3+ (4f (2)) energy levels in GaN SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID RARE-EARTH IONS; CATHODOLUMINESCENCE; SEMICONDUCTORS; LUMINESCENCE; PHOTOLUMINESCENCE; SPECTRA; EXCITATION; INP; ER AB We have calculated the crystal-field splitting of the energy levels of Pr3+ in GaN and have compared these results to an analysis reported recently of the photoluminescence and the cathodoluminescence spectra of Pr3+ implanted in GaN by metal organic chemical vapor deposition on sapphire substrates. The lattice location of Pr in GaN determined recently by the emission channeling technique, provides direct evidence that substitutional Ga sites are thermally stable lattice positions for Pr. The lattice-sum calculations with Pr occupying Ga sites include effective ionic charges, multipole polarizabilities, and structural information also available in the literature. From the calculations, we conclude that the majority of the reported emission spectra is associated with Pr3+ ions in a common site with transitions from excited P-3(0) and P-3(1) states to crystal-field split multiplets, H-3(4) (the ground state), F-3(J), and (1)G(4). (C) 2001 American Institute of Physics. C1 San Jose State Univ, Dept Phys, San Jose, CA 95192 USA. USA, Res Lab, Adelphi Lab Ctr, Adelphi, MD 20783 USA. Ohio Univ, Stocker Ctr, Sch Elect Engn & Comp Sci, Athens, OH 45701 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Gruber, JB (reprint author), San Jose State Univ, Dept Phys, San Jose, CA 95192 USA. NR 36 TC 26 Z9 26 U1 1 U2 13 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD JUN 15 PY 2001 VL 89 IS 12 BP 7973 EP 7976 DI 10.1063/1.1372158 PG 4 WC Physics, Applied SC Physics GA 440PM UT WOS:000169183500044 ER PT J AU Ekdahl, C AF Ekdahl, C TI Transient decay of beam-produced fields in thin-walled tubes SO JOURNAL OF APPLIED PHYSICS LA English DT Article AB An electromagnetics problem that arises in long-pulse beam experiments is the decay of image currents (and their fields) resulting from a beam that is offset from the geometric axis of the beam tube. A related problem, which arises in calibration of beam diagnostics, is that of simulating the beam using a current-carrying conductor. These problems are solved analytically in the limit that the tube walls are thin compared with the magnetic-field penetration depth. It is shown that the transient decay time of the fields for these two cases is different. (C) 2001 American Institute of Physics. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Ekdahl, C (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 2 TC 2 Z9 2 U1 0 U2 0 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD JUN 15 PY 2001 VL 89 IS 12 BP 8214 EP 8218 DI 10.1063/1.1372368 PG 5 WC Physics, Applied SC Physics GA 440PM UT WOS:000169183500083 ER PT J AU Whittle, E Shanklin, J AF Whittle, E Shanklin, J TI Engineering Delta(9)-16 : 0-acyl carrier protein (ACP) desaturase specificity based on combinatorial saturation mutagenesis and logical redesign of the castor Delta(9)-18 : 0-ACP desaturase SO JOURNAL OF BIOLOGICAL CHEMISTRY LA English DT Article ID FATTY-ACID SYNTHESIS; SUBSTRATE-SPECIFICITY; DIRECTED EVOLUTION; ESCHERICHIA-COLI; SEED; EXPRESSION; PLANTS; GENE; BIOSYNTHESIS; FERREDOXIN AB Six amino acid locations in the soluble castor Delta (9)-18:0-acyl carrier protein (ACP) desaturase were identified that can affect substrate specificity. Combinatorial saturation mutagenesis of these six amino acids, in conjunction with selection, using an unsaturated fatty acid auxotroph system, led to the isolation of variants with up to Iii-fold increased specific activity toward 16-carbon substrates. The most improved mutant, com2, contained two substitutions (T117R/G188L) common to five of the 19 complementing variants subjected to further analysis. These changes, when engineered into otherwise wild-type 18:0-ACP desaturase to make mutant 5,2, produced a 35-fold increase in specific activity with respect to le-carbon substrates, Kinetic analysis revealed changes in both k(cat) and K-m that result in an 82-fold improvement in specificity factor for Is-carbon substrate compared with wild-type enzyme. Improved substrate orientation apparently compensated for loss of binding energy that results from the loss of desolvation energy for 16-carbon substrates. Mutant 5.2 had specific activity for 16-carbon substrates 2 orders of magnitude higher than those of known natural 16-carbon specific desaturases. These data support the hypothesis that it should be possible to reengineer archetypal enzymes to achieve substrate specificities characteristic of recently evolved enzymes while retaining the desired stability and/or turnover characteristics of a parental paralog. C1 Brookhaven Natl Lab, Dept Biol, Upton, NY 11973 USA. RP Shanklin, J (reprint author), Brookhaven Natl Lab, Dept Biol, Bldg 463,50 Bell Ave, Upton, NY 11973 USA. NR 36 TC 54 Z9 57 U1 1 U2 7 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 JUN 15 PY 2001 VL 276 IS 24 BP 21500 EP 21505 DI 10.1074/jbc.M102129200 PG 6 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 442RC UT WOS:000169297900094 PM 11294879 ER PT J AU Majumdar, D Roszak, S Balasubramanian, K AF Majumdar, D Roszak, S Balasubramanian, K TI Interaction of benzene (Bz) with Pt and Pt-2: A theoretical study on Bz-Pt-2, Bz(2)-Pt-2, and Bz(3)-Pt-2 clusters SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID RELATIVISTIC EFFECTIVE POTENTIALS; COLLISION-INDUCED DISSOCIATION; SPIN-ORBIT OPERATORS; ELECTRONIC STATES; CHARGE-TRANSFER; GAS-PHASE; METAL; CATIONS; IONS; CHEMISTRY AB Extensive ab initio calculations have been carried out on benzene (Bz)-platinum complexes (Bz-Pt-2, Bz(2)-Pt, Bz(2)-Pt-2, and Bz(3)-Pt-2) using a variety of computational techniques. Both physisorbed structures and energetically lower chemisorbed species were found. Complete active space multiconfiguration self-consistent field (CASMCSCF), multireference singles and doubles configuration-interaction (MRSDCI), density functional (DFT), and Moller-Plessett second order perturbation (MP2) calculations were employed to predict Bz(m)-Pt-n structures. While the DPT and MP2 calculations also consistent with the MRSDCI techniques predict chemisorbed :structures to-be lower, the CASMCSCF method seems to favor physisorbed structures. The effect of spin-orbit. coupling on the binding energies of complexes with the Pt atom and the Pt-2 dimer were considered. The computed dissociation energies are consistent with the relative abundance of these clusters found in the time-of-flight mass spectra. The low-energy staircase structures of Bz(2)-Pt, Bz(2)-Pt-2, and Bz(3)-Pt-2 complexes found in this study could be electrically conducting. (C) 2001 American Institute of Physics. C1 Univ Calif Davis, Dept Appl Sci, Livermore, CA 94550 USA. Univ Calif Lawrence Livermore Natl Lab, Dept Appl Sci, Livermore, CA 94550 USA. Univ Calif Lawrence Livermore Natl Lab, Chem & Mat Sci Directorate, Livermore, CA 94550 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Glenn T Seaborg Ctr, Berkeley, CA 94720 USA. Wroclaw Tech Univ, Inst Phys & Theoret Chem, PL-50370 Wroclaw, Poland. Univ Calif Davis, Dept Appl Sci, Livermore, CA 94550 USA. RP Balasubramanian, K (reprint author), Univ Calif Davis, Dept Appl Sci, Livermore, CA 94550 USA. NR 46 TC 15 Z9 16 U1 0 U2 5 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD JUN 15 PY 2001 VL 114 IS 23 BP 10300 EP 10310 DI 10.1063/1.1373691 PG 11 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 443QR UT WOS:000169352300009 ER PT J AU Balasubramanian, K Zhu, XL AF Balasubramanian, K Zhu, XL TI Spectroscopic constants and potential energy curves of Nb-2 and Nb-2(+) SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID NIOBIUM-CLUSTER ANIONS; ELECTRONIC STATES; MOLECULES; DIMER; SPECTRA; V-2; VNB AB Potential energy curves and;spectroscopic constants for 45 low-lying electronic states of Nb-2, 18 electronic states of Nb-2(+), and 2 low-lying states of Nb-2(-) have been computed using the complete active space multiconfiguration self-consistent field followed by the multireference singles + doubles configuration interaction calculations that included up to 17 million configurations. The equilibrium distances (r(e)), vibrational frequencies (w(e)), and energy separations (T-e) are reported. We have also computed the properties of the two lowest electronic states of Nb-2(-). Possible assignments are suggested for the recently observed fragmentation spectra and three-photon fragmentation spectra of Nb-2(+) as well as the spectra of Nb-2. The dissociation energies. and ionization potentials of Nb-2 and Nb-2(+) as well as electron affinities of Nb-2 are computed. The nature of bonding is discussed using the wave function composition and Mulliken population analysis. (C) 2001 American institute of Physics. C1 Univ Calif, Dept Appl Sci, Livermore, CA 94550 USA. Univ Calif Lawrence Livermore Natl Lab, Chem & Mat Sci Directorate, Livermore, CA 94550 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Glenn T Seaborg Ctr, Berkeley, CA 94720 USA. RP Balasubramanian, K (reprint author), Univ Calif, Dept Appl Sci, Davis Hertz Hall,L-794, Livermore, CA 94550 USA. NR 30 TC 15 Z9 15 U1 0 U2 5 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD JUN 15 PY 2001 VL 114 IS 23 BP 10375 EP 10388 DI 10.1063/1.1373692 PG 14 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 443QR UT WOS:000169352300017 ER PT J AU Zhou, JW Findley, BR Braun, CL Sutin, N AF Zhou, JW Findley, BR Braun, CL Sutin, N TI The separation distance distribution in electron-donor-acceptor systems and the wavelength dependence of free ion yields SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID CHARGE RECOMBINATION PROCESS; ANTHRACENE SINGLE-CRYSTALS; ENERGY-GAP DEPENDENCE; BIOLOGICAL MOLECULES; CARRIER GENERATION; SOLVENT DEPENDENCE; TRANSFER COMPLEXES; COUPLING ELEMENTS; FIELD DEPENDENCE; CONTACT AB We recently reported that free radical ion quantum yields for electron-donor-acceptor (EDA) systems of alkylbenzenes-tetracyanoethylene (TCNE) exhibit a remarkable wavelength-dependence in dichloromethane, a medium polarity solvent. We proposed that weak absorption by long-distance, unassociated or "random'' D...A pairs is-mainly responsible for the free radical ion: yield. Here a model for the wavelength dependence of the free ion yield is developed for four systems in which differing degrees of EDA complex formation are present: 1,3,5-tri-tert-butylbenzene-TCNE in which only random pairs exist due to the bulky groups on the electron donor, and toluene-TCNE, 1,3,5-triethylbenzene-TCNE and 1,3,5-trimethylbenzene-TCNE. Mulliken-Hush theory is used to determine the excitation distance distribution of unassociated, random;pairs at different wavelengths. For each absorption distribution, free radical ion yields at different wavelengths are then calculated using Onsager's result for the ion separation probability. Encouraging agreement between the calculated yields and our experimental results is obtained. As far as we are aware, this is the first time that photoexcitation of unassociated donor/acceptor pairs has been invoked as the source of separated radical ion pairs. (C) 2001 Americarn Institute of Physics. C1 Dartmouth Coll, Dept Chem, Hanover, NH 03755 USA. Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. RP Braun, CL (reprint author), Dartmouth Coll, Dept Chem, Hanover, NH 03755 USA. NR 65 TC 12 Z9 12 U1 0 U2 7 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD JUN 15 PY 2001 VL 114 IS 23 BP 10448 EP 10456 DI 10.1063/1.1372762 PG 9 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 443QR UT WOS:000169352300025 ER PT J AU Xu, L Ogletree, DF Salmeron, M Tang, H Ma, XD Gui, J AF Xu, L Ogletree, DF Salmeron, M Tang, H Ma, XD Gui, J TI Thickness and drainage of perfluoropolyethers under compression SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID SURFACE FORCES APPARATUS; LUBRICANT FILM THICKNESS; POLYMERIC LIQUID-FILMS; PERFLUOROPOLYALKYLETHER FILMS; AMORPHOUS-CARBON; SOLID-SURFACES; TRIBOLOGY; FUNCTIONALITY; SPECTROSCOPY; CONFORMATION AB The Surface Forces Apparatus was used to study the compression and drainage of perfluoropolyethers (PFPEs) between two flat parallel mica surfaces. In the case of Zdols and Demnum-SA, the PFPEs can be squeezed out during slow compression to a final residual film one gyration diameter in thickness. This thickness remained constant up to the highest applied pressure of similar to 10 MPa. The residual thickness for Demnum-SA, with one active end group, was found to be approximately 40% larger than that for Zdol of the same molecular weight, with two active end groups. In contrast, Z03, with no active end groups, could be displaced completely from the contact. The dynamics of expulsion were studied by monitoring the variation of the gap width as a function of time after fast (a few milliseconds) step increase in the compressive load. It was found that Zdol behaves as the bulk liquid down to gap widths of four equivalent gyration diameters. A viscosity increase of more than ten times was observed when the gap width was between four and two gyration diameters. Finally, slow compression to the maximum achievable pressure (similar to 10 MPa) led to a residual layer one gyration diameter in thickness trapped between the mica surfaces. (C) 2001 American Institute of Physics. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Seagate Technol, Fremont, CA 94538 USA. RP Salmeron, M (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 25 TC 7 Z9 7 U1 0 U2 2 PU AMER INST PHYSICS PI MELVILLE PA 2 HUNTINGTON QUADRANGLE, STE 1NO1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD JUN 15 PY 2001 VL 114 IS 23 BP 10504 EP 10509 DI 10.1063/1.1375136 PG 6 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 443QR UT WOS:000169352300032 ER PT J AU Miyabe, K Sotoura, S Guiochon, G AF Miyabe, K Sotoura, S Guiochon, G TI Retention and mass transfer characteristics in reversed-phase liquid chromatography using a tetrahydrofuran-water solution as the mobile phase SO JOURNAL OF CHROMATOGRAPHY A LA English DT Article DE mass transfer; kinetic studies; retention behavior; mobile phase composition; benzenes; toluene; xylenes; naphthalene ID ENTHALPY-ENTROPY COMPENSATION; SURFACE-DIFFUSION PHENOMENA; ACTIVATED CARBON; ADSORPTION CHARACTERISTICS; BONDED PHASES; PERFORMANCE; DEPENDENCE; TEMPERATURE; BEHAVIOR; GEL AB The characteristics of the retention and the mass transfer kinetics in reversed-phase liquid chromatography (RPLC) were measured on a system consisting of a C-18-silica gel and a tetrahydrofuran-water (50:50, v/v) solution. These parameters were derived from the first and the second moments of the elution peaks, respectively. Further information on the thermodynamic properties of this system was derived from the temperature dependence of these moments. Some correlations previously established were confirmed for this system, namely, an enthalpy-entropy. compensation for both retention and surface diffusion and a linear free-energy relationship. These results are compared with those observed in other similar systems using methanol-water (70:30, v/v) and acetonitrile-water (70:30, v/v) solutions. The contribution of surface diffusion to intraparticle diffusion in C-18-silica gel particles was shown to be important. The analysis of the thermodynamic properties of surface diffusion suggests that, in these three RPLC systems, its activation energy is lower than the isosteric heat of adsorption. The nature and the extent of the influence of the mobile phase composition on the parameters describing the retention and the mass transfer kinetics are different but the chromatographic mechanisms involved in RPLC systems appear similar, irrespective of the nature of the organic modifier in the mobile phase. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. Toyama Univ, Fac Educ, Gofu Ku, Toyama 9308555, Japan. Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Guiochon, G (reprint author), Univ Tennessee, Dept Chem, 552 Buehler Hall, Knoxville, TN 37996 USA. NR 53 TC 32 Z9 32 U1 3 U2 9 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0021-9673 J9 J CHROMATOGR A JI J. Chromatogr. A PD JUN 15 PY 2001 VL 919 IS 2 BP 231 EP 244 DI 10.1016/S0021-9673(01)00821-4 PG 14 WC Biochemical Research Methods; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA 442TJ UT WOS:000169300800001 PM 11442028 ER PT J AU Guay, CKH Falkner, KK Muench, RD Mensch, M Frank, M Bayer, R AF Guay, CKH Falkner, KK Muench, RD Mensch, M Frank, M Bayer, R TI Wind-driven transport pathways for Eurasian Arctic river discharge SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID NORTH-ATLANTIC OSCILLATION; SOUTHERN CANADIAN BASIN; FRESH-WATER; SEA-ICE; OCEAN; HALOCLINE; CIRCULATION; TEMPERATURE; BALANCE; TRACER AB Distributions of temperature, salinity, and barium in near-surface waters (depth less than or equal to 50 m) of the Laptev Sea and adjacent areas of the Arctic Ocean are presented for the summers of 1993, 1995, and 1996. The tracer data indicate that while fluvial discharge was largely confined to the shelf region bf the Laptev Sea in the summer of 1993, surface waters containing a significant fluvial component extended beyond the shelf break and over the slope and basin areas north of the Laptev Sea in the summers of 1995 and 1996. These distributions of fluvial discharge are consistent with local winds and suggest two principal pathways by which river waters can enter the central Arctic basins from the Laptev Sea. When southerly to southeasterly wind conditions prevail, river waters are transported northward beyond the shelf break and over the slope and adjacent basin areas. These waters can then enter the interior Arctic Ocean via upper layer flow in the vicinity of the Lomonosov Ridge. Under other wind conditions, river waters are steered primarily along the inner Laptev shelf and into the East Siberian Sea as part of the predominantly eastward coastal current system. These waters then appear to cross the shelf and enter the interior Arctic Ocean via upper layer flow aligned roughly along the Mendeleyev Ridge. The extent to which either pathway is favored in a given year is largely determined by local wind patterns during the summer months, when fluvial discharge is greatest and shelf waters are at the lowest salinity of their annual cycle. C1 Univ Heidelberg, Inst Umweltphys, D-69120 Heidelberg, Germany. Oregon State Univ, Coll Ocean & Atmospher Sci, Corvallis, OR 97331 USA. Earth & Space Res, Seattle, WA 98102 USA. RP Guay, CKH (reprint author), Lawrence Berkeley Natl Lab, Earth Sci Div, 1 Cycoltron Rd,M-S 90-1116, Berkeley, CA 94720 USA. NR 46 TC 56 Z9 56 U1 0 U2 4 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-OCEANS JI J. Geophys. Res.-Oceans PD JUN 15 PY 2001 VL 106 IS C6 BP 11469 EP 11480 DI 10.1029/2000JC000261 PG 12 WC Oceanography SC Oceanography GA 442TU UT WOS:000169301700006 ER PT J AU Flint, AL Flint, LE Bodvarsson, GS Kwicklis, EM Fabryka-Martin, J AF Flint, AL Flint, LE Bodvarsson, GS Kwicklis, EM Fabryka-Martin, J TI Evolution of the conceptual model of unsaturated zone hydrology at Yucca Mountain, Nevada SO JOURNAL OF HYDROLOGY LA English DT Review DE conceptual model; nuclear waste; unsaturated zone; Yucca Mountain; hydrology ID ROCK FRACTURES; FLOW; TUFF AB Yucca Mountain is an arid site proposed for consideration as the United States' first underground high-level radioactive waste repository. Low rainfall (approximately 170 mm/yr) and a thick unsaturated zone (500-1000 m) are important physical attributes of the site because the quantity of water likely to reach the waste and the paths and rates of movement of the water to the saturated zone under future climates would be major factors in controlling the concentrations and times of arrival of radionuclides at the surrounding accessible environment. The framework for understanding the hydrologic processes that occur at this site and that control how quickly water will penetrate through the unsaturated zone to the water table has evolved during the past 15 yr. Early conceptual models assumed that very small volumes of water infiltrated into the bedrock (0.5-4.5 mm/yr, or 2-3 percent of rainfall), that much of the infiltrated water flowed laterally within the upper nonwelded units because of capillary barrier effects, and that the remaining water flowed down faults with a small amount flowing through the matrix of the lower welded, fractured rocks. It was believed that the matrix had to be saturated for fractures to how. However, accumulating evidence indicated that infiltration rates were higher than initially estimated, such as infiltration modeling based on neutron borehole data, bomb-pulse isotopes deep in the mountain, perched water analyses and thermal analyses. Mechanisms supporting lateral diversion did not apply at these higher fluxes, and the flux calculated in the lower welded unit exceeded the conductivity of the matrix, implying vertical flow of water in the high permeability fractures of the potential repository host rock, and disequilibrium between matrix and fracture water potentials. The development of numerical modeling methods and parameter values evolved concurrently with the conceptual model in order to account for the observed field data, particularly fracture flow deep in the unsaturated zone. This paper presents the history of the evolution of conceptual models of hydrology and numerical models of unsaturated zone flow at Yucca Mountain, Nevada (Flint, A.L., Flint, L.E., Kwicklis, E.M., Bodvarsson, G.S., Fabryka-Martin, J.M., 2001. Hydrology of Yucca Mountain. Reviews of Geophysics in press). This retrospective is the basis for recommendations for optimizing the efficiency with which a viable and robust conceptual model can be developed for a complex site. (C) 2001 Elsevier Science B.V. All rights reserved. C1 US Geol Survey, Sacramento, CA 95819 USA. Lawrence Berkeley Natl Lab, Berkeley, CA USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM USA. RP Flint, AL (reprint author), US Geol Survey, Placer Hall,6000 J St, Sacramento, CA 95819 USA. NR 87 TC 52 Z9 53 U1 3 U2 17 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-1694 J9 J HYDROL JI J. Hydrol. PD JUN 15 PY 2001 VL 247 IS 1-2 BP 1 EP 30 DI 10.1016/S0022-1694(01)00358-4 PG 30 WC Engineering, Civil; Geosciences, Multidisciplinary; Water Resources SC Engineering; Geology; Water Resources GA 441MW UT WOS:000169235000001 ER PT J AU Chen, CH Liu, J Amine, K AF Chen, CH Liu, J Amine, K TI Symmetric cell approach and impedance spectroscopy of high power lithium-ion batteries SO JOURNAL OF POWER SOURCES LA English DT Article DE impedance spectroscopy; lithium-ion batteries; electrode process ID ELECTROLYTE SYSTEMS; LI; INTERCALATION; STATE AB High power lithium-ion cells are a very promising energy source for practical hybrid vehicles. It is found that the impedance of the 18650 high-power cells using LiNi0.8Co0.2O2 chemistry increases with time during the beginning period of storage. A symmetric cell approach is developed to distinguish the anode and cathode effects on the impedance rise. Cathode impedance, especially charge-transfer resistance, is identified as the main component of the cell impedance and is most responsible for the rise of the cell impedance during storage at room temperature. With analysis of impedance spectra from a variety of cells, the charge-transfer process is thought to rake place at the interface between the electrolyte solution and the surface of surface layers on the electrode. We also propose that the surface layers might be mixed conductors of electrons and lithium ions, instead of pure lithium-ion conductors. The nature of the surface layers on the cathode is likely different from that of the surface layers on the anode. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Argonne Natl Lab, Electrochem Technol Program, Div Chem Technol, Argonne, IL 60439 USA. RP Amine, K (reprint author), Argonne Natl Lab, Electrochem Technol Program, Div Chem Technol, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Chen, Chunhua/F-5897-2010; Amine, Khalil/K-9344-2013 NR 16 TC 168 Z9 174 U1 16 U2 106 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 JUN 15 PY 2001 VL 96 IS 2 BP 321 EP 328 DI 10.1016/S0378-7753(00)00666-2 PG 8 WC Chemistry, Physical; Electrochemistry; Energy & Fuels; Materials Science, Multidisciplinary SC Chemistry; Electrochemistry; Energy & Fuels; Materials Science GA 442DZ UT WOS:000169271100006 ER PT J AU Burton, HD AF Burton, HD TI The tangled field: Barbara McClintock's search for the patterns of genetic control. SO LIBRARY JOURNAL LA English DT Book Review C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Burton, HD (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 1 TC 0 Z9 0 U1 0 U2 1 PU BOWKER MAGAZINE GROUP CAHNERS MAGAZINE DIVISION PI NEW YORK PA 249 W 17TH ST, NEW YORK, NY 10011 USA SN 0363-0277 J9 LIBR J JI Libr. J. PD JUN 15 PY 2001 VL 126 IS 11 BP 100 EP 100 PG 1 WC Information Science & Library Science SC Information Science & Library Science GA 445LV UT WOS:000169459700185 ER PT J AU Timofeev, E Mirzabekov, A AF Timofeev, E Mirzabekov, A TI Binding specificity and stability of duplexes formed by modified oligonucleotides with a 4096-hexanucleotide microarray SO NUCLEIC ACIDS RESEARCH LA English DT Article ID SEQUENCE-ANALYSIS; HUMAN GENOME; HYBRIDIZATION; DNA; 2-AMINOADENINE; MICROCHIPS; ARRAYS; IDENTIFICATION; IMMOBILIZATION; ANALOG AB The binding of oligodeoxynucleotides modified with adenine 2'-O-methyl riboside, 2,6-diaminopurine 2'-O-methyl riboside, cytosine 2'-O-methyl riboside, 2,6-diaminopurine deoxyriboside or 5-bromodeoxyuridine was studied with a microarray containing all possible (4096) polyacrylamide-bound hexadeoxynucleotides (a generic microchip). The generic microchip was manufactured by using reductive immobilization of aminooligonucleotides in the activated copolymer of acrylamide, bis-acrylamide and N-(2,2-dimethoxyethyl) acrylamide. The binding of the fluorescently labeled modified octanucleotides to the array was analyzed with the use of both melting profiles and the fluorescence distribution at selected temperatures. Up to three substitutions of adenosines in the octamer sequence by adenine 2'-O-methyl ribosides (A(m)), 2,6-diaminopurine 2'-O-methyl ribosides (D-m) or 2,6-diaminopurine deoxyribosides (D) resulted in increased mismatch discrimination measured at the melting temperature of the corresponding perfect duplex. The stability of complexes formed by 2'-O-methyl-adenosine-modified oligodeoxynucleotides was slightly decreased with every additional substitution, yielding similar to4 degreesC of total loss in melting temperature for three modifications, as followed from microchip thermal denaturation experiments. 2,6-Diaminopurine 2'-O-methyl riboside modifications led to considerable duplex stabilization. The cytosine 2'-O-methyl riboside and 5-bromodeoxyuridine modifications generally did not change either duplex stability or mismatch resolution. Denaturation experiments conducted with selected perfect duplexes on microchips and in solution showed similar results on thermal stabilities. Some hybridization artifacts were observed that might indicate the formation of parallel DNA. C1 VA Engelhardt Mol Biol Inst, Moscow 117984, Russia. Argonne Natl Lab, Ctr Biochip Technol, Argonne, IL 60439 USA. RP Mirzabekov, A (reprint author), Argonne Natl Lab, Ctr Biochip Technol, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 29 TC 20 Z9 21 U1 0 U2 2 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0305-1048 J9 NUCLEIC ACIDS RES JI Nucleic Acids Res. PD JUN 15 PY 2001 VL 29 IS 12 BP 2626 EP 2634 DI 10.1093/nar/29.12.2626 PG 9 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 448FK UT WOS:000169616100024 PM 11410672 ER PT J AU Buchko, GW Tung, CS McAteer, K Isern, NG Spicer, LD Kennedy, MA AF Buchko, GW Tung, CS McAteer, K Isern, NG Spicer, LD Kennedy, MA TI DNA-XPA interactions: a P-31 NMR and molecular modeling study of dCCAATAACC association with the minimal DNA-binding domain (M98-F219) of the nucleotide excision repair protein XPA SO NUCLEIC ACIDS RESEARCH LA English DT Article ID NUCLEAR MAGNETIC-RESONANCE; XERODERMA-PIGMENTOSUM; DAMAGE-RECOGNITION; MAMMALIAN-CELLS; CORRELATION SPECTROSCOPY; ESCHERICHIA-COLI; AQUEOUS-SOLUTION; CONFORMATION; COMPLEX; ACIDS AB Recent NMR-based, chemical shift mapping experiments with the minimal DNA-binding domain of XPA (XPA-MBD: M98-F219) suggest that a basic cleft located in the loop-rich subdomain plays a role in DNA-binding. Here, XPA-DNA interactions are further characterized by NMR spectroscopy from the vantage point of the DNA using a single-stranded DNA nonamer, dCCAATAACC (d9). Up to 2.5 molar equivalents of XPA-MBD was titrated into a solution of d9. A subset of P-31 resonances of d9 were observed to broaden and/or shift providing direct evidence that XPA-MBD binds d9 by a mechanism that perturbs the phosphodiester backbone of d9. The interior five residues of d9 broadened and/or shifted before P-31 resonances of phosphate groups at the termini, suggesting that when d9 is bound to XPA-MBD the internal residues assume a correlation time that is characteristic of the molecular weight of the complex while the residues at the termini undergo a fraying motion away from the surface of the protein on a timescale such that the line widths are more characteristic of the molecular weight of ssDNA. A molecular model of the XPA-MBD complex with d9 was calculated based on the N-15 (XPA-MBD) and P-31 (d9) chemical shift mapping studies and on the assumption that electrostatic interactions drive the complex formation. The model shows that a nine residue DNA oligomer fully covers the DNA-binding surface of XPA and that there may be an energetic advantage to binding DNA in the 3'-->5' direction rather than in the 5'-->3' direction (relative to XPA-MBD alpha -helix-3). C1 Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. Duke Univ, Med Ctr, Dept Biochem, Durham, NC 27710 USA. Duke Univ, Med Ctr, Dept Radiobiol, Durham, NC 27710 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Kennedy, MA (reprint author), Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RI Isern, Nancy/J-8016-2013; Buchko, Garry/G-6173-2015; OI Buchko, Garry/0000-0002-3639-1061; Isern, Nancy/0000-0001-9571-8864 FU NIGMS NIH HHS [GM 41829] NR 66 TC 19 Z9 19 U1 1 U2 3 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0305-1048 J9 NUCLEIC ACIDS RES JI Nucleic Acids Res. PD JUN 15 PY 2001 VL 29 IS 12 BP 2635 EP 2643 DI 10.1093/nar/29.12.2635 PG 9 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 448FK UT WOS:000169616100025 PM 11410673 ER PT J AU Krylov, AS Zasedateleva, OA Prokopenko, DV Rouviere-Yaniv, J Mirzabekov, AD AF Krylov, AS Zasedateleva, OA Prokopenko, DV Rouviere-Yaniv, J Mirzabekov, AD TI Massive parallel analysis of the binding specificity of histone-like protein HU to single- and double-stranded DNA with generic oligodeoxyribonucleotide microchips SO NUCLEIC ACIDS RESEARCH LA English DT Article ID ESCHERICHIA-COLI HU; CRUCIFORM DNA; NUCLEIC-ACIDS; OLIGONUCLEOTIDE; FORMS AB A generic hexadeoxyribonucleotide microchip has been applied to test the DNA-binding properties of HU histone-like bacterial protein, which is known to have a low sequence specificity. All 4096 hexamers flanked within 8mers by degenerate bases at both the 3'- and 5'-ends were immobilized within the 100 x100 x 20 mm polyacrylamide gel pads of the microchip, Single-stranded immobilized oligonucleotides were converted in some experiments to the double-stranded form by hybridization with a specified mixture of 8mers. The DNA interaction with HU was characterized by three type of measurements: (i) binding of FITC-labeled HU to microchip oligonucleotides; (ii) melting curves of complexes of labeled HU with single-stranded microchip oligonucleotides; (iii) the effect of HU binding on melting curves of microchip double-stranded DNA labeled with another fluorescent dye, Texas Red, Large numbers of measurements of these parameters were carried out in parallel for all or many generic microchip elements in real time with a multi-wavelength fluorescence microscope. Statistical analysis of these data suggests some preference for HU binding to G/C-rich single-stranded oligonucleotides. HU complexes with double-stranded microchip 8mers can be divided into two groups in which HU binding either increased the melting temperature (T-m) of duplexes or decreased it. The stabilized duplexes showed some preference for presence of the sequence motifs AAG, AGA and AAGA. In the second type of complex, enriched with A/T base pairs, the destabilization effect was higher for longer stretches of A/T duplexes. Binding of HU to labeled duplexes in the second type of complex caused some decrease in fluorescence. This decrease also correlates with the higher A/T content and lower T-m. The results demonstrate that generic microchips could be an efficient approach in analysis of sequence specificity of proteins. C1 Russian Acad Sci, VA Engelhardt Mol Biol Inst, Moscow 119991, Russia. Inst Biol Phys Chim, F-75005 Paris, France. Argonne Natl Lab, BioChip Technol Ctr, Argonne, IL 60439 USA. RP Mirzabekov, AD (reprint author), Russian Acad Sci, VA Engelhardt Mol Biol Inst, 32 Vavilov St, Moscow 119991, Russia. NR 27 TC 46 Z9 53 U1 1 U2 6 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0305-1048 J9 NUCLEIC ACIDS RES JI Nucleic Acids Res. PD JUN 15 PY 2001 VL 29 IS 12 BP 2654 EP 2660 DI 10.1093/nar/29.12.2654 PG 7 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 448FK UT WOS:000169616100027 PM 11410675 ER PT J AU Omenetto, FG Taylor, AJ Moores, MD Reitze, DH AF Omenetto, FG Taylor, AJ Moores, MD Reitze, DH TI Adaptive control of femtosecond pulse propagation in optical fibers SO OPTICS LETTERS LA English DT Article ID MU-M; TRANSMISSION; DISPERSION; GENERATION AB Nonlinear effects present fundamental obstacles to the propagation of femtosecond pulses of detectable energy in single-mode optical fibers, inducing severe distortion even after a very short (a few meters) propagation distance. We show here that adaptive pulse shaping can overcome these limitations by synthesizing pulses that are self-correcting for higher-order nonlinear effects when they are launched in the fiber. This approach would not only affect optical communications but also yield benefits in various disciplines requiring optimized fiber-based femtosecond pulse delivery, for example, nonlinear imaging techniques such as multiphoton microscopy, material processing, and medical diagnostics. (C) 2001 Optical Society of America C1 Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. Univ Florida, Dept Phys, Gainesville, FL 32611 USA. RP Omenetto, FG (reprint author), Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, MST-10,MSK764, Los Alamos, NM 87545 USA. NR 11 TC 47 Z9 47 U1 0 U2 0 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 JUN 15 PY 2001 VL 26 IS 12 BP 938 EP 940 DI 10.1364/OL.26.000938 PG 3 WC Optics SC Optics GA 440QN UT WOS:000169185900026 PM 18040498 ER PT J AU de Oliveira, HP Soares, ID Tonini, EV AF de Oliveira, HP Soares, ID Tonini, EV TI Universality in the chaotic dynamics associated with saddle-centers critical points SO PHYSICA A LA English DT Article DE chaos and universality; saddle-centers; Henon-Heiles Hamiltonian; non-extensive statistical mechanics ID BOUNDARIES; SYSTEMS AB We describe a new statistical pattern characteristic of saddle-center critical points in the dynamics of non-integrable Hamiltonian systems, associated with the partition of the Hamiltonian into rotational motion energy and hyperbolic motion energy pieces in a linear neighborhood of the saddle-center. The distribution of hyperbolic energy of orbits visiting a neighborhood of the saddle-center defines a statistical law that, for a large range of values of the hyperbolic energy, has the form p(z) similar to z(-gamma) in a regime of high nonintegrability. We present numerical evidence to support the conjecture that this pattern is universal for any Hamiltonian system with one or several saddle-centers. The parameter gamma appears as a universal characteristic associated with the chaotic dynamics of saddle-centers. (C) 2001 Elsevier Science B.V. All rights reserved. C1 CNPQ, Ctr Brasileiro Pesquisas Fis, BR-22290 Rio De Janeiro, RJ, Brazil. Fermi Natl Accelerator Lab, NASA Fermilab Astrophys Ctr, Batavia, IL 60510 USA. Univ estado Rio De Janeiro, Inst Fis, Dept Fis Teor, BR-20550013 Rio De Janeiro, RJ, Brazil. Ctr Fed Educ Tenol, CEFETES, BR-29040333 Vitoria, ES, Brazil. RP Soares, ID (reprint author), CNPQ, Ctr Brasileiro Pesquisas Fis, Rua Dr Xavier Sigaud,150, BR-22290 Rio De Janeiro, RJ, Brazil. NR 16 TC 9 Z9 9 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0378-4371 J9 PHYSICA A JI Physica A PD JUN 15 PY 2001 VL 295 IS 3-4 BP 348 EP 358 DI 10.1016/S0378-4371(01)00122-4 PG 11 WC Physics, Multidisciplinary SC Physics GA 444XT UT WOS:000169425900003 ER PT J AU Groves, JR Yashar, PC Arendt, PN DePaula, RF Peterson, EJ Fitzsimmons, MR AF Groves, JR Yashar, PC Arendt, PN DePaula, RF Peterson, EJ Fitzsimmons, MR TI Ultra-thin bi-axially textured IBAD MgO template layers resolved by grazing incidence X-ray diffraction SO PHYSICA C LA English DT Article DE ion beam assisted deposition; high-energy electron diffraction; ion bombardment; X-ray diffraction; bi-axial texture; magnesium oxide ID FILMS; DENSITY AB We describe a method using grazing incidence diffractometry (GID) with a rotating anode X-ray source to measure the in-plane alignment of similar to 10-nm thick MgO films deposited by ion beam assisted deposition (IBAD). In conjunction with these measurements, we have calibrated the IBAD film growth process by monitoring the film in situ with reflected high-energy electron diffraction and comparing the intensity versus time curve with results obtained from the ex situ GID measurements. GID has also been used to identify differences in the observed in-plane texture for samples with and without the addition of a homoepitaxial layer. Improvements in texture after the addition of the homoepitaxial layer are attributed to the healing of ion induced damage during growth of the IBAD layer. Further analysis has revealed that standard X-ray diffraction measurements of these overcoated films do not sufficiently quantify the in-plane alignment of the initial IBAD layers, (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Div Sci Mat, Los Alamos, NM 87545 USA. Univ Calif Los Alamos Natl Lab, Los Alamos Neutron Sci Ctr, Los Alamos, NM 87545 USA. RP Groves, JR (reprint author), Univ Calif Los Alamos Natl Lab, Div Sci Mat, MS K763, Los Alamos, NM 87545 USA. RI Lujan Center, LANL/G-4896-2012 NR 11 TC 10 Z9 10 U1 2 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD JUN 15 PY 2001 VL 355 IS 3-4 BP 293 EP 298 DI 10.1016/S0921-4534(01)00082-X PG 6 WC Physics, Applied SC Physics GA 445VP UT WOS:000169479500015 ER PT J AU Bronold, FX Saxena, A Bishop, AR AF Bronold, FX Saxena, A Bishop, AR TI Dynamics of a single electron in the disordered Holstein model SO PHYSICAL REVIEW B LA English DT Article ID COHERENT-POTENTIAL APPROXIMATION; MEAN-FIELD THEORY; EXCITON-PHONON SYSTEMS; SMALL-POLARON; LA1-XSRXMNO3; SPECTRA; ALLOYS AB We study, at zero temperature, the dynamics of a single electron in a Holstein model augmented by site-diagonal, binary-alloy-type disorder. The average over the phonon vacuum and the alloy configurations is performed within a generalized dynamic coherent potential approximation. We present numerical results for a Bethe lattice with infinite coordination number. In particular, we investigate, in the intermediate electron-phonon coupling regime, the spectral and diffusion properties in the vicinity of the high-energy edge of the lowest polaronic subband. To characterize the diffusion properties, we define a spectrally resolved delocalization time, which is, for a given energy, the characteristic time scale on which the electron leaves a given site. We find the delocalization times substantially enhanced for states with a large phonon content, i.e., in the absence (presence) of alloy-type disorder at the high-energy edge(s) of the polaronic subband (minisubbands). According to their delocalization times, we discriminate between "fast" quasiparticlelike and "sluggish" defectlike polaron states and qualitatively address the issue of trapping of an electronic carrier. C1 Univ Magdeburg, Inst Theoret Phys, D-39016 Magdeburg, Germany. Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Univ Calif Los Alamos Natl Lab, Ctr Nonlinear Studies, Los Alamos, NM 87545 USA. RP Bronold, FX (reprint author), Univ Magdeburg, Inst Theoret Phys, Univ Pl 2, D-39016 Magdeburg, Germany. NR 40 TC 17 Z9 19 U1 2 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 JUN 15 PY 2001 VL 63 IS 23 AR 235109 DI 10.1103/PhysRevB.63.235109 PG 15 WC Physics, Condensed Matter SC Physics GA 445LQ UT WOS:000169459300038 ER PT J AU Choi, IH Yu, PY AF Choi, IH Yu, PY TI Suppression of the anomalous blue shift in the band gap temperature dependence of AgCuGaS2 alloys SO PHYSICAL REVIEW B LA English DT Article ID AGGAS2 AB It has been known for some time that, at temperatures below 100 K, the band gap of AgGaS2 exhibits an anomalous blare shift with increase in temperature. We have found that this anomalous blue shift can be suppressed completely by as little as 1% of Cu in AgCuGa2, alloys. In conjunction with the disappearance of the blue shift, soft-phonon sidebands to the one-phonon Raman peaks are greatly broadened and no longer resolvable as distinct peaks. Our results are consistent with the suggestion that a soft-phonon mode may be responsible for this anomalous blue shift in AgGaS2. C1 Chung Ang Univ, Dept Phys, Seoul 156756, South Korea. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Choi, IH (reprint author), Chung Ang Univ, Dept Phys, Seoul 156756, South Korea. NR 14 TC 4 Z9 4 U1 1 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD JUN 15 PY 2001 VL 63 IS 23 AR 235210 PG 5 WC Physics, Condensed Matter SC Physics GA 445LQ UT WOS:000169459300056 ER PT J AU Devine, RAB Herrera, GV AF Devine, RAB Herrera, GV TI Electric-field-induced transport of protons in amorphous SiO2 SO PHYSICAL REVIEW B LA English DT Article ID INTERFACE TRAP FORMATION; EFFECT TRANSISTORS; MOBILE; CHARGE; STATES AB The temperature and time dependence of electric-field-induced motion of thermally generated protons in 20 nm amorphous SiO2 films has been investigated The short-time behavior is found to involve an activation energy of similar to0.38 eV and a hopping distance of similar to0.55 nm. The activation energy is considerably smaller than that found for radiation-generated proton motion (similar to0.82 eV). The hopping distance is consistent with transport involving motion between a bridging oxygen atom and a next-nearest-neighbor (or farther) bridging oxygen atom; this suggests that motion is primarily via cross-ring hopping. C1 Univ New Mexico, Ctr High Technol Mat, Albuquerque, NM 87106 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Devine, RAB (reprint author), Univ New Mexico, Ctr High Technol Mat, 1313 Goddard SE, Albuquerque, NM 87106 USA. NR 16 TC 8 Z9 8 U1 1 U2 8 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 JUN 15 PY 2001 VL 63 IS 23 AR 233406 DI 10.1103/PhysRevB.63.233406 PG 4 WC Physics, Condensed Matter SC Physics GA 445LQ UT WOS:000169459300027 ER PT J AU Evans, JW Bartelt, MC AF Evans, JW Bartelt, MC TI Nucleation, adatom capture, and island size distributions: Unified scaling analysis for submonolayer deposition SO PHYSICAL REVIEW B LA English DT Article ID THIN-FILM GROWTH; RATE-EQUATIONS; ENVIRONMENT DEPENDENCE; EPITAXIAL-GROWTH; CU/CO ISLANDS; DYNAMICS; RU(0001) AB We consider the irreversible nucleation and growth of two-dimensional islands during submonolayer deposition in the regime of large island sizes. A quasihydrodynamic analysis of rate equations for island densities yields an ordinary differential equation (ODE) for the scaling function describing the island size distribution. This ODE involves the scaling function for the dependence on island size of ''capture numbers'' describing the aggregation of diffusing adatoms. The latter is determined via a quasihydrodynamic analysis of rate equations for the areas of "capture zones" surrounding islands. Alternatively, a more complicated analysis yields a partial differential equation (PDE) for the scaling function describing the joint probability distribution for island sizes and capture zone areas. Then, applying a moment analysis to this PDE, we obtain refined versions of the above ODE's, together with a third equation for the variance of the cell area distribution (for islands of a given size). The key nontrivial input to the above equations is a detailed characterization of nucleation. We analyze these equations for a general formulation of nucleation, as well as for an idealized picture considered previously, wherein nucleated islands have capture zones lying completely within those of existing islands. C1 Iowa State Univ, Dept Math, Ames, IA 50011 USA. Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Lawrence Livermore Natl Lab, Dept Chem & Mat Sci, Livermore, CA 94550 USA. RP Evans, JW (reprint author), Iowa State Univ, Dept Math, Ames, IA 50011 USA. NR 27 TC 45 Z9 46 U1 1 U2 3 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 JUN 15 PY 2001 VL 63 IS 23 AR 235408 DI 10.1103/PhysRevB.63.235408 PG 15 WC Physics, Condensed Matter SC Physics GA 445LQ UT WOS:000169459300087 ER PT J AU Fehske, H Kinateder, M Wellein, G Bishop, AR AF Fehske, H Kinateder, M Wellein, G Bishop, AR TI Quantum lattice effects in mixed-valence transition-metal chain complexes SO PHYSICAL REVIEW B LA English DT Article ID LOCALIZED MODES; GROUND-STATE; 2-BAND MODEL; SYSTEMS; SPECTRUM; PHONONS; CDW AB Inspired by the recent observation of intrinsically localized vibrational modes in halide-bridged transition-metal chain complexes [Swanson et al. Phys. Rev. Lett. 82, 3288 (1999)], we study strong-coupling effects between electronic and lattice degrees of freedom on the basis of a two-band, 3/4-filled Peierls-Hubbard model. Combining a very efficient Jacobi-Davidson algorithm with the maximum entropy method, the low-energy physics of the Peierls-Hubbard model is analyzed in finite chains with high accuracy, preserving the full dynamics of the Raman- and infrared-active phonon modes. Results far several experimental observables, including the valence disproportionation, local magnetic moments, lattice distortions, spin and charge structure factors, and optical response are discussed. The redshift of the overtone resonance Raman spectrum is calculated to be in quantitative agreement with the experimental data found for isotopically pure (PtCl)-Cl-37. Most significantly, the numerical results provide clear evidence of the existence of spatially localized multiphonon bound states in quasi-one-dimensional charge-density-wave systems with strong electron-lattice coupling. C1 Univ Bayreuth, Inst Phys, D-95440 Bayreuth, Germany. Univ Erlangen Nurnberg, Reg Rech Zentrum Erlangen, D-91058 Erlangen, Germany. Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Univ Calif Los Alamos Natl Lab, Ctr Nonlinear Studies, Los Alamos, NM 87545 USA. LRZ Munchen, Munich, Germany. NIC Julich, Julich, Germany. HLR Stuttgart, Stuttgart, Germany. RP Fehske, H (reprint author), Univ Bayreuth, Inst Phys, POB 101251, D-95440 Bayreuth, Germany. NR 37 TC 14 Z9 14 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 JUN 15 PY 2001 VL 63 IS 24 AR 245121 DI 10.1103/PhysRevB.63.245121 PG 14 WC Physics, Condensed Matter SC Physics GA 446TX UT WOS:000169531200034 ER PT J AU Ismail Plummer, EW Lazzeri, M de Gironcoli, S AF Ismail Plummer, EW Lazzeri, M de Gironcoli, S TI Surface oscillatory thermal expansion: Mg(10(1)over-bar0) SO PHYSICAL REVIEW B LA English DT Article ID AL(110) SURFACE; ANHARMONICITY; CONTRACTION; RELAXATIONS; AG(111); SOLIDS AB Temperature-dependent low-energy electron diffraction I-V measurements and density-functional calculations within the quasiharmonic approximation reveal that the Mg(10 (1) over bar1) surface exhibits a remarkable oscillatory surface thermal expansion, thermal contraction in the short interlayer, and thermal expansion in the long interlayer. The thermal expansion of the long interlayer is intimately tied to the thermal contraction in the short interlayer in the surface region. C1 Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Princeton Univ, Dept Chem, Princeton, NJ 08544 USA. Scuola Int Super Studi Avanzati, I-34014 Trieste, Italy. INFM, I-34014 Trieste, Italy. RP Ismail (reprint author), Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. RI de Gironcoli, Stefano/G-7236-2011; Lazzeri, Michele/N-7615-2016 OI de Gironcoli, Stefano/0000-0002-2307-0998; Lazzeri, Michele/0000-0002-6644-6617 NR 29 TC 12 Z9 13 U1 0 U2 2 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 JUN 15 PY 2001 VL 63 IS 23 AR 233401 DI 10.1103/PhysRevB.63.233401 PG 3 WC Physics, Condensed Matter SC Physics GA 445LQ UT WOS:000169459300022 ER PT J AU Lee, SJ Cho, BK Canfield, PC Lynch, DW AF Lee, SJ Cho, BK Canfield, PC Lynch, DW TI Optical properties of RNi2B2C (R = Y,Tb,Er,Dy) SO PHYSICAL REVIEW B LA English DT Article ID ELECTRONIC-STRUCTURE; SUPERCONDUCTING GAP; BORIDE CARBIDE; YNI2B2C; LUNI2B2C; LU AB The optical properties of single crystals of RNi2B2C (R = Y, Tb, Er, and Dy) were measured between 1.7 and 5.2 eV at room temperature using a spectroscopic ellipsometer. The spectra for all compounds are similar and the peak positions appear in a similar energy region. The similarity of the spectra of RNi2B2C (R = Tb, Er, Dy) to that of YNi2B2C indicates that the rare-earth 4f states are not actively involved in the optical transitions. C1 Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. K JIST, Dept Mat Sci & Technol, Kwang Joo 500712, South Korea. Iowa State Univ Sci & Technol, Dept Phys & Astron, Ames, IA 50011 USA. RP Lee, SJ (reprint author), Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. RI Canfield, Paul/H-2698-2014 NR 23 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 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD JUN 15 PY 2001 VL 63 IS 23 AR 233103 PG 3 WC Physics, Condensed Matter SC Physics GA 445LQ UT WOS:000169459300003 ER PT J AU Levine, G Muthukumar, VN AF Levine, G Muthukumar, VN TI Localization transition in the Mermin model SO PHYSICAL REVIEW B LA English DT Article ID DISSIPATIVE 2-STATE SYSTEM; 2-LEVEL SYSTEM; DYNAMICS AB We study the dynamical properties of the Mermin model, a simple quantum dissipative model with a monochromatic environment, using analytical and numerical methods. Our numerical results show that the model exhibits a second order phase transition to a localized state before which the system is effectively decoupled from the environment. In contrast to the spin-boson model, the Mermin model exhibits an "orthogonality catastrophe,'' defining the critical point, before dissipation has destroyed all coherent behavior. An analytic approach based on the Liouvillian technique, although successful in describing the phase diagram of spin-boson and related models, fails to capture this essential feature of the Mermin model. C1 Hofstra Univ, Dept Phys, Hempstead, NY 11550 USA. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Princeton Univ, Joseph Henry Labs Phys, Princeton, NJ 08544 USA. RP Levine, G (reprint author), Hofstra Univ, Dept Phys, Hempstead, NY 11550 USA. NR 10 TC 2 Z9 2 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 JUN 15 PY 2001 VL 63 IS 24 AR 245112 DI 10.1103/PhysRevB.63.245112 PG 5 WC Physics, Condensed Matter SC Physics GA 446TX UT WOS:000169531200025 ER PT J AU Liang, Y Gan, SP Chambers, SA Altman, EI AF Liang, Y Gan, SP Chambers, SA Altman, EI TI Surface structure of anatase TiO2(001): Reconstruction, atomic steps, and domains SO PHYSICAL REVIEW B LA English DT Article ID TITANIUM-DIOXIDE; TIO2; FILMS; TIO2(110); GROWTH; RUTILE AB The surface structure of anatase TiO2(001) was investigated using scanning tunneling microscopy (STM), x-ray photoelectron spectroscopy (XPS), reflection high-energy electron diffraction (RHEED), and low-energy electron diffraction (LEED). A two-domain (1 x 4)/(4 x 1) reconstruction, similar to those previously reported in LEED and ion scattering studies, was observed by STM and RHEED. This reconstruction was found to be stable not only from room temperature to 850 degreesC in ultrahigh vacuum and oxygen-rich environments, but also during the anatase film growth. High-resolution STM images obtained at positive sample biases revealed two types of atomic row within each surface unit cell, indicating different Ti-derived states at the surface. At the same time, XPS of the reconstructed surfaces showed no evidence of Ti3+. Based on the STM, XPS, RHEED, and LEED results, an ''added''-and-''missing''-row model is proposed to account for the (1x4) reconstruction. Atomic steps and their relationship to the population of (1x4) and (4x1) domains were also investigated. The results showed that for vicinal surfaces the domain population depended strongly on the overall surface step orientation. While populations of the (1x4) and the (4x1) domains were nearly equal on flat (001) surfaces, they became significantly lopsided on a surface with its normal 2 degrees away from the (001) direction, demonstrating a strong correlation between surface steps and domain population on vicinal surfaces. C1 Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. Yale Univ, Dept Chem Engn, New Haven, CT 06520 USA. RP Liang, Y (reprint author), Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. EM Yong.Liang@pnl.gov NR 21 TC 117 Z9 118 U1 6 U2 72 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 JUN 15 PY 2001 VL 63 IS 23 AR 235402 DI 10.1103/PhysRevB.63.235402 PG 7 WC Physics, Condensed Matter SC Physics GA 445LQ UT WOS:000169459300081 ER PT J AU Lovenich, R Schumacher, AB Dodge, JS Chemla, DS Miller, LL AF Lovenich, R Schumacher, AB Dodge, JS Chemla, DS Miller, LL TI Evidence of phonon-mediated coupling between charge transfer and ligand field excitons in Sr2CuO2Cl2 SO PHYSICAL REVIEW B LA English DT Article ID TEMPERATURE-DEPENDENCE; ELECTRONIC-STRUCTURE; CUO2 PLANE; EXCITATIONS; ABSORPTION; SPECTRA AB We present a comparative experimental and theoretical investigation of the two-dimensional charge transfer gap in the strongly correlated material Sr2CuO2Cl2. We observe an Urbach behavior in the absorption profile over a surprisingly wide range of energies and temperatures. We present a model that accounts for phonon scattering to infinite order and that allows us to explain the data accurately by assuming coupling of the charge transfer gap exciton to lower-energy electronic excitations. C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. EO Lawrence Berkeley Natl Lab, Div Sci Mat, Berkeley, CA 94720 USA. Univ Karlsruhe, Inst Angew Phys, D-76128 Karlsruhe, Germany. Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Phys, Ames, IA 50011 USA. RP Schumacher, AB (reprint author), Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. NR 18 TC 10 Z9 10 U1 0 U2 3 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 JUN 15 PY 2001 VL 63 IS 23 AR 235104 PG 6 WC Physics, Condensed Matter SC Physics GA 445LQ UT WOS:000169459300033 ER PT J AU Mascarenhas, A Cheong, HM Alsina, F Geisz, JF Olson, JM AF Mascarenhas, A Cheong, HM Alsina, F Geisz, JF Olson, JM TI Reply to "Comment on 'Phonon modes in spontaneously ordered GaInP2 studied by micro-Raman measurements' " SO PHYSICAL REVIEW B LA English DT Editorial Material ID SCATTERING C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Mascarenhas, A (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. RI Alzina, Francesc/C-5468-2008; Cheong, Hyeonsik/D-7424-2012 OI Alzina, Francesc/0000-0002-7082-0624; Cheong, Hyeonsik/0000-0002-2347-4044 NR 6 TC 0 Z9 0 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD JUN 15 PY 2001 VL 63 IS 24 AR 247202 PG 2 WC Physics, Condensed Matter SC Physics GA 446TX UT WOS:000169531200088 ER PT J AU Reboredo, FA Zunger, A AF Reboredo, FA Zunger, A TI Surface-passivation-induced optical changes in Ge quantum dots SO PHYSICAL REVIEW B LA English DT Article ID SILICON NANOCRYSTALS; SI NANOCRYSTALS; CONFINEMENT; EXCITONS; COULOMB AB One of the most interesting properties of quantum dots is the possibility to tune the band gap as a function of their size. Here we explore the possibility of changing the lifetime of the lowest-energy excited state by altering the surface passivation. We show that a moderately electronegative passivation;potential can induce long-lived excitons without appreciable changes to the band gap. In addition, for such passivation the symmetry of the valence-band maximum is gamma (8 upsilon) (t(1) derived) instead of the more usual gamma (8) (upsilon) (t(2) derived). This reverses the effect of the exchange interaction on the bright-dark exciton splitting. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Reboredo, FA (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. RI Reboredo, Fernando/B-8391-2009; Zunger, Alex/A-6733-2013 NR 18 TC 29 Z9 29 U1 0 U2 6 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 JUN 15 PY 2001 VL 63 IS 23 AR 235314 DI 10.1103/PhysRevB.63.235314 PG 7 WC Physics, Condensed Matter SC Physics GA 445LQ UT WOS:000169459300070 ER PT J AU Sales, BC Chakoumakos, BC Jin, R Thompson, JR Mandrus, D AF Sales, BC Chakoumakos, BC Jin, R Thompson, JR Mandrus, D TI Structural, magnetic, thermal, and transport properties of X8Ga16Ge30 (X = Eu, Sr, Ba) single crystals SO PHYSICAL REVIEW B LA English DT Article ID FILLED SKUTTERUDITE ANTIMONIDES; THERMOELECTRIC PROPERTIES; CONDUCTIVITY; GE; HEAT; SN AB Structural, magnetic, electrical and thermal transport, and heat-capacity measurements are reported on single crystals of Eu8Ca16Ge30, Sr8Ga16Ge30, and Ba8Ga16Ge30. These compounds all crystallize in a cubic type-I ice clathrate structure, and are of interest as potential thermoelectric materials. Neutron-diffraction measurements were made on a single crystal of Eu8Ga16Ge30 that was grown using isotopically pure Eu-153. Nuclear density maps clearly show that Eu atoms at the 6d sites (1/4,1/2,0) can move away from the cage center to one of four nearby positions. Ferromagnetism is observed in Eu8Ga16Ge30 for temperatures below 32 K, with the preferred direction of the Eu spins along the (100) axis. Ferromagnetism in these heavily doped semiconductors (approximate to 10(21) electrons/cm(3)) is likely due to a Rudermann-Kittel-Kasuya-Yoshida-type interaction. A large (approximate to 10% at 8 T) negative magnetoresistance was measured near the Curie temperature of Eu8Ga16Ge30 The lattice thermal conductivities of Eu8Ga16Ge30 and Sr8Ga16Ge30 single crystals show all of the characteristics of a structural glass. The thermal conductivity of Ba8Ga16Ge30 is low at room temperature (1.3 W/m K), but exhibits a temperature dependence characteristic of a crystal. A magnetic field has no significant effect on the thermal conductivity of any of the crystals for temperatures between 2 and 300 K. Heat-capacity measurements indicated Einstein contributions from each of the rattlers, with characteristic temperatures of 60, 53, and 30 R for Ba, Sr, and Eu atoms respectively. No superconductivity was observed in heavily doped single crystals of Ba8Ga16Ge30 for temperatures above 2 K, contrary to a previous report. C1 Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Sales, BC (reprint author), Oak Ridge Natl Lab, Div Solid State, POB 2008, Oak Ridge, TN 37831 USA. RI Mandrus, David/H-3090-2014; Chakoumakos, Bryan/A-5601-2016 OI Chakoumakos, Bryan/0000-0002-7870-6543 NR 36 TC 328 Z9 334 U1 7 U2 89 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 JUN 15 PY 2001 VL 63 IS 24 AR 245113 DI 10.1103/PhysRevB.63.245113 PG 8 WC Physics, Condensed Matter SC Physics GA 446TX UT WOS:000169531200026 ER PT J AU Seong, MJ Mascarenhas, A Olson, JM Cheong, HM AF Seong, MJ Mascarenhas, A Olson, JM Cheong, HM TI Anisotropy of phonon modes in spontaneously ordered GaInP2 SO PHYSICAL REVIEW B LA English DT Article ID VAPOR-PHASE EPITAXY; RAMAN-SCATTERING; PHOTOLUMINESCENCE; SPECTRA; ALLOYS AB The anisotropy associated with angular variation of the phonon wave vector q with respect to the ordering axis z' of a spontaneously ordered GaInP2 with order parameter eta congruent to0.46 is studied by carefully performing micro-Raman measurements in scattering geometries where q is either parallel or perpendicular to z'. The LO mode at similar to 380 cm(-1) and the TO mode at similar to 330 cm(-1) exhibit distinct phonon frequency shifts of - 1.2 cm(-1) and +2.1 cm(-1), respectively, as the angle phi between q and z' varies from 0 degrees to 90 degrees. This small angular dispersion is explained on the basis of the bond-stiffening along the ordering axis with increasing order parameter eta, providing strong evidence for a small A(1)-E splitting in comparison to the large LO-TO splitting for these modes. In addition, an even larger angular dispersion, +2.5 cm(-1), for the vibrational mode at similar to 354 cm(-1) is observed. Two additional phonon modes, which have previously been labeled as missing to account for all nine Raman-active optical modes, are observed and experimentally identified with E(x) and E(y) tensors. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. Sogang Univ, Dept Phys, Seoul 121742, South Korea. RP Seong, MJ (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. RI Cheong, Hyeonsik/D-7424-2012 OI Cheong, Hyeonsik/0000-0002-2347-4044 NR 15 TC 4 Z9 4 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD JUN 15 PY 2001 VL 63 IS 23 AR 235205 DI 10.1103/PhysRevB.63.235205 PG 5 WC Physics, Condensed Matter SC Physics GA 445LQ UT WOS:000169459300051 ER PT J AU Subramania, G Biswas, R Constant, K Sigalas, MM Ho, KM AF Subramania, G Biswas, R Constant, K Sigalas, MM Ho, KM TI Structural characterization of thin film photonic crystals SO PHYSICAL REVIEW B LA English DT Article ID ORDERED MACROPOROUS MATERIALS; COLLOIDAL SYSTEMS; BAND-GAPS; PROPAGATION; REFLECTION; EMISSION; SPHERES; TITANIA AB We quantitatively analyze the structure of thin film inverse-opal photonic crystals composed of ordered arrays of air pores in a background of titania. Ordering of the sphere template and introduction of the titania background were performed simultaneously in the thin film photonic crystals. Nondestructive optical measurements of backfilling with high refractive index liquids, angle-resolved reflectivity, and optical spectroscopy were combined with band-structure calculations. The analysis reveals a thin film photonic crystal structure with a very high filling fraction (92-94%) of air and a substantial compression along the c axis (similar to 22-25%). C1 Iowa State Univ, Ames Lab, Dept Phys & Astron, Ames, IA 50011 USA. Iowa State Univ, Ctr Microelect Res, Ames, IA 50011 USA. Iowa State Univ, Dept Mat Sci & Engn, Ames, IA 50011 USA. RP Subramania, G (reprint author), Iowa State Univ, Ames Lab, Dept Phys & Astron, Ames, IA 50011 USA. RI Constant, Kristen/C-3673-2014 OI Constant, Kristen/0000-0001-7138-9365 NR 25 TC 15 Z9 17 U1 0 U2 5 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD JUN 15 PY 2001 VL 63 IS 23 AR 235111 DI 10.1103/PhysRevB.63.235111 PG 7 WC Physics, Condensed Matter SC Physics GA 445LQ UT WOS:000169459300040 ER PT J AU Tonjes, WC Greanya, VA Liu, R Olson, CG Molinie, P AF Tonjes, WC Greanya, VA Liu, R Olson, CG Molinie, P TI Charge-density-wave mechanism in the 2H-NbSe2 family: Angle-resolved photoemission studies SO PHYSICAL REVIEW B LA English DT Article ID TRANSITION-METAL DICHALCOGENIDES; FERMI-SURFACE; 2H-TASE2; SUPERCONDUCTIVITY AB We report high-resolution angle resolved photoemission studies of 2H-NbSe2 and 2H-TaS2. Results are compared to those of 2H-TaSe2. We find that the normal stare electronic structures in this family of materials have the same basic characteristics. Their Fermi surface consists of a pocket around Gamma and another one around K. They ail exhibit a saddle band near EF along T-K. A finite energy gap is observed in the saddle band region and on the Fermi surface around K in 2H-TaS2 and 2H-TaSe2. Gapping on the Fermi surface around Gamma was not observed. We suggest that the charge density waves in this family of materials originate from a combination of the partial nesting of the Fermi surface around K and the saddle band. C1 Michigan State Univ, Dept Phys & Astron, E Lansing, MI 48824 USA. Ames Lab, Ames, IA 50011 USA. CNRS, IMN, F-44322 Nantes, France. RP Tonjes, WC (reprint author), Michigan State Univ, Dept Phys & Astron, E Lansing, MI 48824 USA. NR 23 TC 32 Z9 32 U1 2 U2 15 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 JUN 15 PY 2001 VL 63 IS 23 AR 235101 DI 10.1103/PhysRevB.63.235101 PG 5 WC Physics, Condensed Matter SC Physics GA 445LQ UT WOS:000169459300030 ER PT J AU van Schilfgaarde, M Mryasov, ON AF van Schilfgaarde, M Mryasov, ON TI Anomalous exchange interactions in III-V dilute magnetic semiconductors SO PHYSICAL REVIEW B LA English DT Article ID FERROMAGNETISM; (IN,MN)AS; (GA,MN)AS AB Based on local-density functional calculations, we study the exchange interactions between magnetic dopants Cr, Mn, and Fe in the III-V compounds GaAs, GaN, and AlN. We show the magnetic exchange interactions deviate strongly in behavior expected from simple models, and may explain the observed maximum in critical temperature with impurity concentration. Additionally the magnetism is responsible for a strong, short-range attraction between the magnetic dopants, thus creating an anomalous effective alloy hamiltonian. This suggests that the impurities may aggregate into small nanoclusters of a few magnetic atoms. C1 Sandia Natl Labs, Livermore, CA 94551 USA. RP van Schilfgaarde, M (reprint author), Sandia Natl Labs, Livermore, CA 94551 USA. NR 11 TC 249 Z9 249 U1 2 U2 21 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 JUN 15 PY 2001 VL 63 IS 23 AR 233205 PG 4 WC Physics, Condensed Matter SC Physics GA 445LQ UT WOS:000169459300014 ER PT J AU Wang, LW AF Wang, LW TI Calculations of carrier localization in InxGa1-xN SO PHYSICAL REVIEW B LA English DT Article ID CHEMICAL-VAPOR-DEPOSITION; RESONANT RAMAN-SCATTERING; LIGHT-EMITTING DIODES; QUANTUM DOTS; LASER-DIODES; (GA,IN)(AS,N) ALLOYS; PHASE-SEPARATION; PHOTOLUMINESCENCE; WELLS; SEMICONDUCTORS AB The electronic structures of cubic InGaN systems are calculated using an atomistic empirical pseudopotential method. Two extreme cases are studied. One is a pure InN quantum dot embedded in a pure GaN matrix, another is a pure InxGa1-xN alloy without clustering. We find hole localizations in both cases. The hole wave function starts to be localized as soon as a few In atoms segregate to form a small cluster, while the electron wave function only becomes localized after the number of In atoms in the quantum dot becomes larger than 200. The hole state is also strongly localized in a pure InxGa1-xN ahoy, on top of randomly formed (110) directioned In-N-In chains. Using one proposed model, we have calculated the hole energy fluctuation, and related that to photoluminescence linewidth. The calculated Linewidth is about 100 meV, close to the experimental results. Wurtzite InGaN is also studied for optical anisotropies. We find that in both quantum dot and pure alloy, the polarization is in the xy plane perpendicular to the c axis of the wurtzite structure. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Natl Energy Res Sci Comp Ctr, Berkeley, CA 94720 USA. RP Wang, LW (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Natl Energy Res Sci Comp Ctr, Berkeley, CA 94720 USA. NR 36 TC 39 Z9 39 U1 0 U2 8 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 JUN 15 PY 2001 VL 63 IS 24 AR 245107 DI 10.1103/PhysRevB.63.245107 PG 7 WC Physics, Condensed Matter SC Physics GA 446TX UT WOS:000169531200020 ER PT J AU Wu, GQ Neumeier, JJ Hundley, MF AF Wu, GQ Neumeier, JJ Hundley, MF TI Magnetic susceptibility, heat capacity, and pressure dependence of the electrical resistivity of La3Ni2O7 and La4Ni3O10 SO PHYSICAL REVIEW B LA English DT Article ID METAL-INSULATOR-TRANSITION; TEMPERATURE ELECTRONIC-PROPERTIES; EQUALS RARE-EARTH; NEUTRON-DIFFRACTION; PHYSICAL-PROPERTIES; BAND-STRUCTURE; PEROVSKITES; LANIO3; LA2NIO4; SM AB The magnetic susceptibility chi, heat capacity, and electrical resistivity rho under pressure have been measured on La3Ni2O7 and La4Ni3O10. Heat-capacity measurements reveal electronic heat-capacity coefficients with magnitudes comparable to those of common metals. A weak feature in rho and chi appears in both samples near T(c)approximate to 130 K, which could result from either a charge-transfer gap or charge-density wave (CDW). Pressure decreases rho, and drives T-c down at rates of -10.7 and -6.9 K/GPa for La3Ni2O7 and La4Ni3O10, respectively. The results suggest that the CDW picture be given more serious consideration. C1 Florida Atlantic Univ, Dept Phys, Boca Raton, FL 33431 USA. Univ Calif Los Alamos Natl Lab, Condensed Matter & Thermal Phys Grp, Los Alamos, NM 87545 USA. RP Wu, GQ (reprint author), Florida Atlantic Univ, Dept Phys, Boca Raton, FL 33431 USA. NR 29 TC 14 Z9 14 U1 3 U2 14 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 JUN 15 PY 2001 VL 63 IS 24 AR 245120 PG 5 WC Physics, Condensed Matter SC Physics GA 446TX UT WOS:000169531200033 ER PT J AU Chalmers, G Siegel, W AF Chalmers, G Siegel, W TI Simplifying algebra in Feynman graphs. III. Massive vectors SO PHYSICAL REVIEW D LA English DT Article ID DUAL YANG-MILLS; GAUGE-THEORIES; MULTIPLE BREMSSTRAHLUNG; HELICITY AMPLITUDES; GLUON AMPLITUDES; LOOP AMPLITUDES; COLLINEAR LIMITS; QCD AMPLITUDES; HIGH-ENERGIES; SELF-DUALITY AB A T-dualized self-dual inspired formulation of massive vector fields coupled to arbitrary matter is generated; subsequently its perturbative series modeling a spontaneously broken gauge theory is analyzed. The new Feynman rules and external line factors are chirally minimized in the sense that only one type of spin index occurs in the rules. Several processes are examined in detail and the cross sections formulated in this approach. A double Line formulation of the Lorentz algebra for Feynman diagrams is produced in this formalism, similar to color ordering, which follows from a spin ordering of the Feynman rules. The new double line formalism leads to further minimization of gauge invariant scattering in perturbation theory. The dualized electroweak model is also generated. C1 Argonne Natl Lab, Div High Energy Phys, Argonne, IL 60439 USA. SUNY Stony Brook, CN Yang Inst Theoret Phys, Stony Brook, NY 11794 USA. RP Chalmers, G (reprint author), Argonne Natl Lab, Div High Energy Phys, 9700 S Cass Ave, Argonne, IL 60439 USA. EM chalmers@pc19.hep.anl.gov; siegel@insti.physics.sunysb.edu NR 55 TC 6 Z9 6 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 JUN 15 PY 2001 VL 63 IS 12 AR 125027 DI 10.1103/PhysRevD.63.125027 PG 20 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 442LZ UT WOS:000169288400072 ER PT J AU Fraga, ES Pisarski, RD Schaffner-Bielich, J AF Fraga, ES Pisarski, RD Schaffner-Bielich, J TI Small, dense quark stars from perturbative QCD SO PHYSICAL REVIEW D LA English DT Article ID THERMAL-LOOP RESUMMATION; GAUGE VECTOR-MESONS; GROUND-STATE ENERGY; 3-LOOP FREE-ENERGY; HOT GLUON PLASMA; FINITE-TEMPERATURE; NEUTRON-STARS; COLOR SUPERCONDUCTIVITY; PHASE-TRANSITIONS; STRANGE STARS AB As a model for nonideal behavior in the equation of state of QCD at high density, we consider cold quark matter in perturbation theory. To second order in the strong coupling constant alpha (s), the results depend sensitively on the choice of the renormalization mass scale. Certain choices of this scale correspond to a strongly first order chiral transition, and generate quark stars with maximum masses and radii approximately half that of ordinary neutron stars. At the center of these stars, quarks are essentially massless. C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Brookhaven Natl Lab, RIKEN BNL Res Ctr, Upton, NY 11973 USA. RP Fraga, ES (reprint author), Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RI Fraga, Eduardo/H-6010-2016 OI Fraga, Eduardo/0000-0001-5340-156X NR 73 TC 146 Z9 146 U1 1 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 JUN 15 PY 2001 VL 63 IS 12 AR 121702 DI 10.1103/PhysRevD.63.121702 PG 5 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 442LZ UT WOS:000169288400003 ER PT J AU Hagmann, C Chang, S Sikivie, P AF Hagmann, C Chang, S Sikivie, P TI Axion radiation from strings SO PHYSICAL REVIEW D LA English DT Article ID STRONG CP PROBLEM; PSEUDO-GOLDSTONE BOSONS; QCD PHASE-TRANSITION; COSMIC STRINGS; INVISIBLE AXION; GLOBAL STRINGS; EARLY UNIVERSE; DOMINATED UNIVERSE; GALAXY FORMATION; HARMLESS AXION AB This paper examines the problem of the string decay contribution to the axion cosmological energy density. We show that this contribution is proportional to the average relative increase when axion strings decay of a certain quantity N-ax which we define. We carry out numerical simulations of the evolution and decay of circular and non-circular string loops, of bent strings with ends held fixed, and of vortex-antivortex pairs in two dimensions. In the case of string loops and of vortex-antivortex pairs, N-ax decreases by approximately 20%. In the case of bent strings, N-ax remains constant or increases slightly. Our results imply that the string decay contribution to the axion energy density is of the same order of magnitude as the well-understood contribution from vacuum realignment. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Purdue Univ, Dept Phys, W Lafayette, IN 47907 USA. Univ Florida, Dept Phys, Gainesville, FL 32611 USA. RP Hagmann, C (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 59 TC 33 Z9 33 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 JUN 15 PY 2001 VL 63 IS 12 AR 125018 DI 10.1103/PhysRevD.63.125018 PG 12 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 442LZ UT WOS:000169288400063 ER PT J AU Venugopalan, R Wirstam, J AF Venugopalan, R Wirstam, J TI Hard thermal loops and beyond in the finite temperature world-line formulation of QED SO PHYSICAL REVIEW D LA English DT Article ID QUARK-GLUON PLASMA; CLASSICAL TRANSPORT-THEORY; HOT GAUGE-THEORIES; MECHANICAL PATH-INTEGRALS; DIMENSIONAL REDUCTION; GREENS-FUNCTIONS; FIELD-THEORY; FREE-ENERGY; QUANTUM CHROMODYNAMICS; QCD AB We derive the hard thermal loop action for soft electromagnetic fields in the finite temperature world-line formulation at imaginary time by first integrating out the hard fermion modes from the microscopic QED action. Further, using the finite T world-line method, we calculate all static higher order terms in the soft electromagnetic field. At hi,oh T, the leading non-linear terms are independent of the temperature and, except for a term quartic in the time component of the vector potential, they cancel exactly against the vacuum contribution. The remaining T-dependent non-linear terms become more strongly suppressed by the temperature as the number of soft fields increases, thus making the expansion reliable. C1 Brookhaven Natl Lab, RIKEN BNL Res Ctr, Upton, NY 11973 USA. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Venugopalan, R (reprint author), Brookhaven Natl Lab, RIKEN BNL Res Ctr, Upton, NY 11973 USA. NR 55 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 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD JUN 15 PY 2001 VL 63 IS 12 AR 125022 DI 10.1103/PhysRevD.63.125022 PG 15 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 442LZ UT WOS:000169288400067 ER PT J AU Milton, SV Gluskin, E Arnold, ND Benson, C Berg, W Biedron, SG Borland, M Chae, YC Dejus, RJ Den Hartog, PK Deriy, B Erdmann, M Eidelmann, YI Hahne, MW Huang, Z Kim, KJ Lewellen, JW Li, Y Lumpkin, AH Makarov, O Moog, ER Nassiri, A Sajaev, V Soliday, R Tieman, BJ Trakhtenberg, EM Travish, G Vasserman, IB Vinokurov, NA Wang, XJ Wiemerslage, G Yang, BX AF Milton, SV Gluskin, E Arnold, ND Benson, C Berg, W Biedron, SG Borland, M Chae, YC Dejus, RJ Den Hartog, PK Deriy, B Erdmann, M Eidelmann, YI Hahne, MW Huang, Z Kim, KJ Lewellen, JW Li, Y Lumpkin, AH Makarov, O Moog, ER Nassiri, A Sajaev, V Soliday, R Tieman, BJ Trakhtenberg, EM Travish, G Vasserman, IB Vinokurov, NA Wang, XJ Wiemerslage, G Yang, BX TI Exponential gain and saturation of a self-amplified spontaneous emission free-electron laser SO SCIENCE LA English DT Article ID FEL AB Self-amplified spontaneous emission in a free-electron Laser has been proposed for the generation of very high brightness coherent x-rays. This process involves passing a high-energy, high-charge, short-pulse, low-energy-spread, and low-emittance electron beam through the periodic magnetic field of a long series of high-quality undulator magnets. The radiation produced grows exponentially in intensity until if reaches a saturation point. We report on the demonstration of self-amplified spontaneous emission gain, exponential growth, and saturation at visible (530 nanometers) and ultraviolet (385 nanometers) wavelengths. Good agreement between theory and simulation indicates that scaling to much shorter wavelengths may be possible. These results confirm the physics behind the self-amplified spontaneous emission process and forward the development of an operational x-ray free-electron laser. C1 Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. Lund Univ, MAX Lab, S-22100 Lund, Sweden. Budker Inst Nucl Phys, Novosibirsk 630090, Russia. RP Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. EM milton@aps.anl.gov RI Travish, Gil/H-4937-2011; OI Travish, Gil/0000-0002-4787-0949; Li, Yuelin/0000-0002-6229-7490 NR 29 TC 161 Z9 170 U1 4 U2 20 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 USA SN 0036-8075 EI 1095-9203 J9 SCIENCE JI Science PD JUN 15 PY 2001 VL 292 IS 5524 BP 2037 EP 2041 DI 10.1126/science.1059955 PG 5 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 442KP UT WOS:000169284700037 PM 11358995 ER PT J AU Hu, JT Li, LS Yang, WD Manna, L Wang, LW Alivisatos, AP AF Hu, JT Li, LS Yang, WD Manna, L Wang, LW Alivisatos, AP TI Linearly polarized emission from colloidal semiconductor quantum rods SO SCIENCE LA English DT Article ID CDSE NANOCRYSTALS; II-VI; DOTS; SPECTROSCOPY; LUMINESCENCE; COMPOSITES; CLUSTERS; POLYMER; GROWTH AB Colloidal quantum rods of cadmium selenide (CdSe) exhibit linearly polarized emission. Empirical pseudopotential calculations predict that slightly elongated CdSe nanocrystals have polarized emission along the long axis, unlike spherical dots, which emit plane-polarized light. Single-molecule luminescence spectroscopy measurements on CdSe quantum rods with an aspect ratio between 1 and 30 confirm a sharp transition from nonpolarized to purely linearly polarized emission at an aspect ratio of 2. Linearly polarized luminescent chromophores are highly desirable in a variety of applications. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Sci Mat, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Natl Energy Res Sci Comp Ctr, Berkeley, CA 94720 USA. RP Alivisatos, AP (reprint author), Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. RI Manna, Liberato/G-2339-2010; Alivisatos , Paul /N-8863-2015 OI Manna, Liberato/0000-0003-4386-7985; Alivisatos , Paul /0000-0001-6895-9048 FU NCRR NIH HHS [1 R01 RR-14891-01] NR 32 TC 880 Z9 905 U1 20 U2 185 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 JUN 15 PY 2001 VL 292 IS 5524 BP 2060 EP 2063 DI 10.1126/science.1060810 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 442KP UT WOS:000169284700042 PM 11337589 ER PT J AU Yan, YF Al-Jassim, MM Jones, KM AF Yan, YF Al-Jassim, MM Jones, KM TI Characterization of extended defects in polycrystalline CdTe thin films grown by close-spaced sublimation SO THIN SOLID FILMS LA English DT Article DE cadmium telluride (CdTe); structure properties; transmission electron microscopy (TEM) ID SOLAR-CELL; CDS/CDTE AB The extended defects in polycrystalline CdTe thin films grown by close-spaced sublimation are characterized by means of high-resolution transmission electron microscopy. We found that the extended defects are mostly lamellar twins and intrinsic and extrinsic stacking faults. The stacking faults always propagate across the grains without ending at a partial dislocation inside the grains. The atomic structures of the defects are confirmed. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Yan, YF (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 10 TC 21 Z9 21 U1 2 U2 9 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0040-6090 J9 THIN SOLID FILMS JI Thin Solid Films PD JUN 15 PY 2001 VL 389 IS 1-2 BP 75 EP 77 DI 10.1016/S0040-6090(01)00841-0 PG 3 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA 444BN UT WOS:000169378200013 ER PT J AU Rodriguez-Navarro, AB AF Rodriguez-Navarro, AB TI Model of texture development in polycrystalline films growing on amorphous substrates with different topographies SO THIN SOLID FILMS LA English DT Article DE crystallographic texture; microstructure; anisotropic grain growth; structure zone model; competitive growth ID THIN-FILMS; DIAMOND GROWTH; GRAIN-GROWTH; DEPOSITION; ELECTROMIGRATION; MICROSTRUCTURE; MORPHOLOGY; DIMENSIONS AB A two-dimensional computer model is presented to study the development of microstructure and crystallographic texture in polycrystalline films growing on amorphous substrates, which often exhibit strong textures. In particular, the analysis focuses on the influence of growth parameters such as the crystal habit, the relative growth rate along different crystal directions, the nucleation density on the substrate surface and the substrate topography. The simulation explains the development of fiber and in-plane textures in polycrystalline films growing from randomly oriented nuclei. These textures result from a geometric selection of the orientation of crystals, mainly due to differences in growth rates along different crystal directions. The calculated distribution of crystal orientations and its evolution with time are In agreement with textures observed in films deposited under growth conditions, corresponding to zone 2 of the structure zone model. The growth of crystals composing of a polycrystalline film is mainly constrained by the growth of adjacent crystals and the geometry of the environment where crystal growth takes place. For instance, average lateral crystal size scales with time as a power law, the exponent varying as a function of the curvature and/or topography of the substrate. (C) 2001 Elsevier Science B.V. All rights reserved. C1 Univ Granada, CSIC, Inst Andaluz Ciencias Tierra, Lab Estudios Cristalograficos, Granada 18002, Spain. RP Rodriguez-Navarro, AB (reprint author), Savannah River Ecol Lab, Drawer E, Aiken, SC 29802 USA. NR 38 TC 24 Z9 24 U1 0 U2 6 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0040-6090 J9 THIN SOLID FILMS JI Thin Solid Films PD JUN 15 PY 2001 VL 389 IS 1-2 BP 288 EP 295 DI 10.1016/S0040-6090(01)00863-X PG 8 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA 444BN UT WOS:000169378200044 ER PT J AU Hathorn, BC Marcus, RA AF Hathorn, BC Marcus, RA TI Estimation of vibrational frequencies and vibrational densities of states in isotopically substituted nonlinear triatomic molecules SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID INTRAMOLECULAR THEORY; OZONE; SPECTROSCOPY; PROGRAM AB For use in unimolecular reactions, a simple method is introduced for obtaining the unknown vibration frequencies: of the many asymmetric isotopomers of a molecule from those of the symmetric ones. The method is illustrated for a triatomic molecule XYZ, ozone. It is based on the neglect of a single G;matrix element in the GF expression for XYZ, yielding for it a block-factored expression of the XYX type for the frequencies of all the isotopomers XYZ. It agrees with available data to the accuracy needed, a few cm(-1). The first-order perturbation vanishes. (The zeroth-order case is not a symmetric molecule since it contains all three masses.) PL Simple second-order perturbation result for-the GF matrix using data for one asymmetric isotopomer then provides agreement to about 1 cm(-1). The virtues of the method are its simplicity, transparency, and,novelty, though normally one would use much more general methods such as ASYM 20 or 40. The method itself is not restricted to triatomic molecules. C1 Oak Ridge Natl Lab, Div Math & Comp Sci, Oak Ridge, TN 37831 USA. CALTECH, Arthur Amos Noyes Lab Chem Phys, Pasadena, CA 91125 USA. RP Marcus, RA (reprint author), Oak Ridge Natl Lab, Div Math & Comp Sci, Oak Ridge, TN 37831 USA. NR 24 TC 8 Z9 8 U1 0 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5639 J9 J PHYS CHEM A JI J. Phys. Chem. A PD JUN 14 PY 2001 VL 105 IS 23 BP 5586 EP 5589 DI 10.1021/jp003849a PG 4 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 443YM UT WOS:000169371200011 ER PT J AU Kim, JH Li, X Wang, LS de Clercq, HL Fancher, CA Thomas, OC Bowen, KH AF Kim, JH Li, X Wang, LS de Clercq, HL Fancher, CA Thomas, OC Bowen, KH TI Vibrationally resolved photoelectron spectroscopy of MgO- and ZnO- and the low-lying electronic states of MgO, MgO-, and ZnO SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID INFRARED-SPECTRA; SOLID ARGON; ZINC ATOMS; TRANSITION; ION; MOLECULE; SYSTEMS; OXYGEN; ALKALI; ANIONS AB Vibrationally resolved photoelectron spectra of MgO- and ZnO- have been recorded at several photon energies under varied experimental conditions. Peaks in these highly structured spectra have been assigned to photodetachment transitions from the MgO- and ZnO- ground state (X (2)Sigma (+)) to vibrational progressions in the ground and several low lying neutral excited states. In addition, a high-temperature MgO- spectrum shows spectral features due to photodetachment from an excited electronic state of the MgO- anion, which has been assigned to an A(2)Pi: anionic state. From the MgO- spectra, the electron affinity of the MgO ground state (X (1)Sigma (+)) is determined to be 1.630 (0.025) eV. Four electronic excited states of MgO, a(3)Pi, A(1)Pi, b(3)Sigma (+), and B(1)Sigma (+), were found to lie 2510, 3390, 8390; and 20 000 cm(-1) above the X (1)Sigma (+) neutral ground state, respectively. The excited MgO- A(2)Pi anion state was found to lie 4791 cm(-1) above the MgO- X (2)Sigma (+) anion ground state. The photoelectron spectra of ZnO-, presented here at higher photon energies, extend a previous photoelectron study by Fancher et al, to the first two excited neutral states, a(3)Pi and A(1)Pi, which have been found to lie 2460 and 4960 cm(-1) above the X (1)Sigma (+) ground state, respectively. From Franck-Condon analyses of the well-resolved vibrational progressions for each electronic transition, equilibrium internuclear distances and fundamental vibrational frequencies of the MgO and ZnO neutral electronic states were determined. Moreover, because the sources employed produced vibrationally hot anions, the bond length and vibrational frequencies of both the MgO- ground and excited states were found from the vibrational hot band transitions. C1 Washington State Univ, Dept Phys, Richland, WA 99352 USA. Pacific NW Natl Lab, W R Wiley Environm Mol Sci Lab, Richland, WA 99352 USA. Johns Hopkins Univ, Dept Chem, Baltimore, MD 21218 USA. RP Wang, LS (reprint author), Washington State Univ, Dept Phys, 2710 Univ Dr, Richland, WA 99352 USA. NR 42 TC 40 Z9 43 U1 2 U2 11 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 JUN 14 PY 2001 VL 105 IS 23 BP 5709 EP 5718 DI 10.1021/jp010331d PG 10 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 443YM UT WOS:000169371200026 ER PT J AU Rodriguez, JA Perez, M Jirsak, T Gonzalez, L Maiti, A Larese, JZ AF Rodriguez, JA Perez, M Jirsak, T Gonzalez, L Maiti, A Larese, JZ TI DeNO(x) reactions on MgO(100), ZnxMg1-x(100), Cr(x)Mg1-(x)(100), and Cr2O3(0001): Correlation between electronic and chemical properties of mixed-metal oxides SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID TOTAL-ENERGY CALCULATIONS; SOLID-SOLUTION CATALYSTS; ULTRAVIOLET PHOTOELECTRON; TIO2(110) SURFACE; NITRIC-OXIDE; THIN-FILMS; ADSORPTION; CHEMISORPTION; MGO; NO AB The rational design of catalysts with a high efficiency for the destruction of NOx compounds (DeNO(x) process) is a major problem in environmental chemistry. The adsorption of NO, NO2, and N2O on MgO(100), Zn-0.06- Mg0.94O(100), Cr0.06Mg0.94O(100), and Cr2O3(0001) was studied using high-resolution photoemission and first-principles density-functional calculations. Important differences were found in the chemistry of the adsorbed NO, species, but in general our results show a clear correlation between the electronic properties and reactivity of the oxide surfaces. Systems that have occupied electronic states with a relatively low stability, Cr0.06Mg0.94O(100) and Cr2O3(0001), bond NO strongly apd are able to induce the dissociation of NO2 and N2O at temperatures as low as 80 K. On these oxide surfaces, adsorbed NO is a main product in the dissociation of NO2, whereas adsorbed N-x species are produced upon decomposition of N2O. The trends in the behavior of ZnxMg1-xO(100) and CrxMg1-xO(100) illustrate a basic principle for the design of mixed-metal oxide catalysts in DeNO(x) operations. The general idea is to find metal dopants that upon hybridization within an oxide matrix produce occupied electronic states located well above the valence band of the oxide. These hybrid dopant states lead to large adsorption energies for NO, species and facilitate N-O bond cleavage. The validity of this basic principle is confirmed after examining the bonding of NO and N2O to a series of TM0.06Mg0.94O-(100) surfaces (TM = Zn, Sn, Ni, Co, Fe, Mn, or Cr). The effects of different metal dopants on the electronic properties of MgO are discussed. C1 Brookhaven Natl Lab, Dept Chem, Upton, NY 11953 USA. Cent Univ Venezuela, Fac Ciencias, Caracas 1020A, Venezuela. Mol Simulat Inc, San Diego, CA 92121 USA. RP Rodriguez, JA (reprint author), Brookhaven Natl Lab, Dept Chem, Upton, NY 11953 USA. NR 82 TC 30 Z9 31 U1 0 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 JUN 14 PY 2001 VL 105 IS 23 BP 5497 EP 5505 DI 10.1021/jp010633f PG 9 WC Chemistry, Physical SC Chemistry GA 443YP UT WOS:000169371400018 ER PT J AU Borisov, AB Cameron, S Luk, TS Nelson, TR Van Tassle, AJ Santoro, J Schroeder, WA Dai, Y Longworth, JW Boyer, K Rhodes, CK AF Borisov, AB Cameron, S Luk, TS Nelson, TR Van Tassle, AJ Santoro, J Schroeder, WA Dai, Y Longworth, JW Boyer, K Rhodes, CK TI Bifurcation mode of relativistic and charge-displacement self-channelling SO JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS LA English DT Article ID X-RAY-EMISSION; UNDERDENSE PLASMA; XE(L) EMISSIONS; LASER-PULSES; PROPAGATION; CLUSTERS; XE(M) AB Stable self-channelling of ultra-powerful (Po similar to 1 TW-1 PW) laser pulses in dense plasmas is a key process for many applications requiring the controlled compression of power at high levels, Theoretical computations predict that the transition zone between the stable and highly unstable regimes of relativistic/charge-displacement self-channelling is well characterized by a form of weak instability that involves bifurcation of the propagating energy into two channels. Recent observations of unstable behaviour with femtosecond 248 nm pulses reveal a mode of bifurcation that corresponds well to these theoretical predictions. It is further experimentally shown that the use of a suitable longitudinal gradient in the plasma density can eliminate this unstable response and restore the efficient formation of single stable channels. C1 Univ Illinois, Dept Phys MC 273, Chicago, IL 60607 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. Tokyo Inst Technol, Dept Math & Comp Sci, Meguro Ku, Tokyo 1528552, Japan. IIT, Dept Phys, Chicago, IL 60616 USA. RP Borisov, AB (reprint author), Univ Illinois, Dept Phys MC 273, Chicago, IL 60607 USA. NR 23 TC 13 Z9 13 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0953-4075 J9 J PHYS B-AT MOL OPT JI J. Phys. B-At. Mol. Opt. Phys. PD JUN 14 PY 2001 VL 34 IS 11 BP 2167 EP 2176 DI 10.1088/0953-4075/34/11/309 PG 10 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 449CA UT WOS:000169665700013 ER PT J AU Orme, CA Noy, A Wierzbicki, A McBride, MT Grantham, M Teng, HH Dove, PM DeYoreo, JJ AF Orme, CA Noy, A Wierzbicki, A McBride, MT Grantham, M Teng, HH Dove, PM DeYoreo, JJ TI Formation of chiral morphologies through selective binding of amino acids to calcite surface steps SO NATURE LA English DT Article ID FREE-ENERGIES; ELECTROSTATIC POTENTIALS; CRYSTAL NUCLEATION; AQUEOUS-SOLUTION; GROWTH; CRYSTALLIZATION; INTERFACES; SOLVATION; MODEL; DIFFRACTION AB Many living organisms contain biominerals and composites with finely tuned properties, reflecting a remarkable level of control over the nucleation, growth and shape of the constituent crystals(1-6). Peptides and proteins play an important role in achieving this control(1,7,8). But the general view that organic molecules affect mineralization through stereochemical recognition, where geometrical and chemical constraints dictate their binding to a mineral, seems difficult to reconcile(4) with a mechanistic understanding, where crystallization is controlled by thermodynamic and kinetic factors(9). Indeed, traditional crystal growth models emphasize the inhibiting effect of so-called 'modifiers' on surface-step growth, rather than stereochemical matching to newly expressed crystal facets. Here we report in situ atomic force microscope observations and molecular modelling studies of calcite growth in the presence of chiral amino acids that reconcile these two seemingly divergent views. We rnd that enantiomer-specific binding of the amino acids to those surface-step edges that offer the best geometric and chemical rt changes the step-edge free energies, which in turn results in macroscopic crystal shape modifications. Our results emphasize that the mechanism underlying crystal modification through organic molecules is best understood by considering both stereochemical recognition and the effects of binding on the interfacial energies of the growing crystal. C1 Univ Calif Lawrence Livermore Natl Lab, Dept Chem & Mat Sci, Livermore, CA 94551 USA. Univ S Alabama, Dept Chem, Mobile, AL 36688 USA. Virginia Polytech Inst & State Univ, Dept Geol Sci, Blacksburg, VA 24061 USA. George Washington Univ, Dept Earth & Environm Sci, Washington, DC 20052 USA. RP Orme, CA (reprint author), Univ Calif Lawrence Livermore Natl Lab, Dept Chem & Mat Sci, Livermore, CA 94551 USA. RI Dove, Patricia/A-7911-2010; Orme, Christine/A-4109-2009 NR 34 TC 424 Z9 428 U1 15 U2 172 PU MACMILLAN PUBLISHERS LTD PI LONDON PA PORTERS SOUTH, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD JUN 14 PY 2001 VL 411 IS 6839 BP 775 EP 779 DI 10.1038/35081034 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 441TV UT WOS:000169246400042 PM 11459051 ER PT J AU Aniol, KA Armstrong, DS Averett, T Baylac, M Burtin, E Calarco, J Cates, GD Cavata, C Chai, Z Chang, CC Chen, JP Chudakov, E Cisbani, E Coman, M Dale, D Deur, A Djawotho, P Epstein, MB Escoffier, S Ewell, L Falletto, N Finn, JM Fleck, A Frois, B Frullani, S Gao, J Garibaldi, F Gasparian, A Gerstner, GM Gilman, R Glamazdin, A Gomez, J Gorbenko, V Hansen, O Hersman, F Higinbotham, DW Holmes, R Holtrop, M Humensky, B Incerti, S Iodice, M de Jager, CW Jardillier, J Jiang, X Jones, MK Jorda, J Jutier, C Kahl, W Kelly, JJ Kim, DH Kim, MJ Kim, MS Kominis, I Kooijman, E Kramer, K Kumar, KS Kuss, M LeRose, J De Leo, R Leuschner, M Lhuillier, D Liang, M Liyanage, N Lourie, R Madey, R Malov, S Margaziotis, DJ Marie, F Markowitz, P Martino, J Mastromarino, P McCormick, K McIntyre, J Meziani, ZE Michaels, R Milbrath, B Miller, GW Mitchell, J Morand, L Neyret, D Petratos, GG Pomatsalyuk, R Price, JS Prout, D Pussieux, T Quemener, G Ransome, RD Relyea, D Roblin, Y Roche, J Rutledge, GA Rutt, PM Rvachev, M Sabatie, F Saha, A Souder, PA Spradlin, M Strauch, S Suleiman, R Templon, J Teresawa, T Thompson, J Tieulent, R Todor, L Tonguc, BT Ulmer, PE Urciuoli, GM Vlahovic, B Wijesooriya, K Wilson, R Wojtsekhowski, B Woo, R Xu, W Younus, I Zhang, C AF Aniol, KA Armstrong, DS Averett, T Baylac, M Burtin, E Calarco, J Cates, GD Cavata, C Chai, Z Chang, CC Chen, JP Chudakov, E Cisbani, E Coman, M Dale, D Deur, A Djawotho, P Epstein, MB Escoffier, S Ewell, L Falletto, N Finn, JM Fleck, A Frois, B Frullani, S Gao, J Garibaldi, F Gasparian, A Gerstner, GM Gilman, R Glamazdin, A Gomez, J Gorbenko, V Hansen, O Hersman, F Higinbotham, DW Holmes, R Holtrop, M Humensky, B Incerti, S Iodice, M de Jager, CW Jardillier, J Jiang, X Jones, MK Jorda, J Jutier, C Kahl, W Kelly, JJ Kim, DH Kim, MJ Kim, MS Kominis, I Kooijman, E Kramer, K Kumar, KS Kuss, M LeRose, J De Leo, R Leuschner, M Lhuillier, D Liang, M Liyanage, N Lourie, R Madey, R Malov, S Margaziotis, DJ Marie, F Markowitz, P Martino, J Mastromarino, P McCormick, K McIntyre, J Meziani, ZE Michaels, R Milbrath, B Miller, GW Mitchell, J Morand, L Neyret, D Petratos, GG Pomatsalyuk, R Price, JS Prout, D Pussieux, T Quemener, G Ransome, RD Relyea, D Roblin, Y Roche, J Rutledge, GA Rutt, PM Rvachev, M Sabatie, F Saha, A Souder, PA Spradlin, M Strauch, S Suleiman, R Templon, J Teresawa, T Thompson, J Tieulent, R Todor, L Tonguc, BT Ulmer, PE Urciuoli, GM Vlahovic, B Wijesooriya, K Wilson, R Wojtsekhowski, B Woo, R Xu, W Younus, I Zhang, C TI New measurement of parity violation in elastic electron-proton scattering and implications for strange form factors SO PHYSICS LETTERS B LA English DT Article ID MAGNETIC-MOMENT; MATRIX-ELEMENTS; NEUTRAL-CURRENT; NUCLEON; BARYONS; RADIUS; LOOPS; MODEL AB We have measured the parity-violating electroweak asymmetry in the elastic scattering of polarized electrons from the proton. The result is A = -15.05 +/- 0.98(stat) +/- 0.56(syst) ppm at the kinematic point (theta (lab)) = 12.3 degrees and (Q(2)) = 0.477 (GeV/c)(2). Both errors are a factor of two smaller than those of the result reported previously. The value for the strange form factor extracted from the data is (G(E)(s) + 0.392 G(M)(s)) = 0.025 +/- 0.020 +/- 0.014. where the first error is experimental and the second arises from the uncertainties in electromagnetic form factors. This measurement is the first fixed-target parity violation experiment that used either a "strained" GaAs photocathode to produce highly polarized electrons or a Compton polarimeter to continuously monitor the electron beam polarization. (C) 2001 Published by Elsevier Science B.V. C1 Calif State Univ Los Angeles, Los Angeles, CA 90032 USA. Coll William & Mary, Williamsburg, VA 23187 USA. Univ Virginia, Charlottesville, VA 22901 USA. TRIUMF, Vancouver, BC V6T 2A3, Canada. Tohoku Univ, Sendai, Miyagi 9890, Japan. Temple Univ, Philadelphia, PA 19122 USA. Syracuse Univ, Syracuse, NY 13244 USA. SUNY Stony Brook, Stony Brook, NY 11794 USA. CEA Saclay, DAPNIA, SPhN, F-91191 Gif Sur Yvette, France. Rutgers State Univ, Piscataway, NJ 08855 USA. Univ Regina, Regina, SK S4S 0A2, Canada. Princeton Univ, Princeton, NJ 08544 USA. Old Dominion Univ, Norfolk, VA 23508 USA. N Carolina Cent Univ, Durham, NC 27707 USA. Norfolk State Univ, Norfolk, VA 23504 USA. Univ New Hampshire, Durham, NH 03824 USA. Univ New Hampshire, Durham, NH 03824 USA. MIT, Cambridge, MA 02139 USA. Univ Massachusetts, Amherst, MA 01003 USA. Univ Maryland, College Pk, MD 20742 USA. Kyungpook Natl Univ, Taegu 702701, South Korea. Kharkov Phys & Technol Inst, UA-310108 Kharkov, Ukraine. Univ Kentucky, Lexington, KY 40506 USA. Kent State Univ, Kent, OH 44242 USA. Thomas Jefferson Natl Accelerator Lab, Newport News, VA 23606 USA. Ist Nazl Fis Nucl, Sezione Sanita, I-00161 Rome, Italy. Ist Nazl Fis Nucl, Sezione Roma 3, I-00146 Rome, Italy. Ist Nazl Fis Nucl, Sezione Bari, I-70126 Bari, Italy. Univ Bari, I-70126 Bari, Italy. Harvard Univ, Cambridge, MA 02138 USA. Hampton Univ, Hampton, VA 23668 USA. Univ Georgia, Athens, GA 30602 USA. Univ Grenoble 1, F-38041 Grenoble, France. Florida Int Univ, Miami, FL 33199 USA. Eastern Kentucky Univ, Richmond, KY 40475 USA. Univ Blaise Pascal, IN2P3, F-63177 Clermont Ferrand, France. RP Finn, JM (reprint author), Calif State Univ Los Angeles, Los Angeles, CA 90032 USA. RI Kominis, Iannis/C-5515-2011; Averett, Todd/A-2969-2011; Kuss, Michael/H-8959-2012; Higinbotham, Douglas/J-9394-2014; McIntyre, Justin/P-1346-2014; Sabatie, Franck/K-9066-2015; CAVATA, Christian/P-6496-2015; Cisbani, Evaristo/C-9249-2011; OI Higinbotham, Douglas/0000-0003-2758-6526; McIntyre, Justin/0000-0002-3706-4310; Sabatie, Franck/0000-0001-7031-3975; Cisbani, Evaristo/0000-0002-6774-8473; Jorda, Jean-Paul/0000-0003-0216-591X; Glamazdin, Alexander/0000-0002-4172-7324; Incerti, Sebastien/0000-0002-0619-2053 NR 38 TC 104 Z9 105 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 J9 PHYS LETT B JI Phys. Lett. B PD JUN 14 PY 2001 VL 509 IS 3-4 BP 211 EP 216 DI 10.1016/S0370-2693(01)00446-4 PG 6 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 444XY UT WOS:000169426400003 ER PT J AU Smolanczuk, R AF Smolanczuk, R TI Production and decay of element 120 SO PHYSICS LETTERS B LA English DT Article DE superheavy elements; element 120; alpha-decay energy and half-life; spontaneous-fission half-life ID COLD-FUSION REACTIONS; SUPERHEAVY NUCLEI; HALF-LIVES AB We discuss decay properties of nuclei predicted to be a result of a sequence of decays initiated by a so far undiscovered element 120. This element might be obtained in the reaction Pb-208(126)(Sr-88(50), 1n)(295)120(175). The synthesis of (295)120(175), if successful, might be observed by measurement of alpha -decay energy and half-life for nuclei in its decay chain. (C) 2001 Published by Elsevier Science B.V. C1 Soltan Inst Nucl Studies, Nucl Theory Dept, PL-00681 Warsaw, Poland. Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. RP Smolanczuk, R (reprint author), Soltan Inst Nucl Studies, Nucl Theory Dept, Hoza 69, PL-00681 Warsaw, Poland. NR 27 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 J9 PHYS LETT B JI Phys. Lett. B PD JUN 14 PY 2001 VL 509 IS 3-4 BP 227 EP 230 DI 10.1016/S0370-2693(01)00591-3 PG 4 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 444XY UT WOS:000169426400005 ER PT J AU Engler, O Kong, XW Lucke, K AF Engler, O Kong, XW Lucke, K TI Recrystallisation textures of particle-containing Al-Cu and Al-Mn single crystals SO ACTA MATERIALIA LA English DT Article DE recrystallisation & recovery; nucleation, growth; texture, aluminium alloys; single crystal ID RECRYSTALLIZATION TEXTURES; STIMULATED NUCLEATION; DEFORMED ALUMINUM; GROWTH SELECTION; ALLOYS; ORIGIN; MICROSTRUCTURE; DEFORMATION; NUCLEI; PHASE AB The influence of second-phase particles on the recrystallisation textures of rolled Al-Cu and Al-Mn single crystals is studied. Single crystals with the initial orientations (011)[100], (011)[21 (1) over bar], (112)[11 (1) over bar] and (001)[100] are investigated by means of X-ray pole figure measurements and TEM microstructure analysis. The recrystallisation textures are interpreted in terms of a growth selection out of a limited spectrum of nucleus orientations. In the case of stable initial orientations the nucleus spectrum is produced by the lattice rotations within the deformation zones around the second-phase particles. For unstable orientations the nucleus spectrum can be attributed to the relation paths during the orientation changes upon rolling deformation (orientation splitting or rotations). During the subsequent growth selection, orientations with a 40 degrees [111] orientation relation to the rolling texture prevail and, thus, form the recrystallisation textures observed. Interestingly, this preference of grains with a 40 degrees [111] orientation relation occurs at the very early phases of recrystallisation, right at the transition from a potential nucleus to a recrystallised grain. This process is labelled micro-growth selection. (C) 2001 Acta Materialia Inc. Published by Elsevier Science Lid. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. Rhein Westfal TH Aachen, Inst Met Kunde & Met Phys, D-52056 Aachen, Germany. RP Engler, O (reprint author), VAW Aluminium AG, Res & Dev, POB 2468, D-53014 Bonn, Germany. NR 39 TC 36 Z9 42 U1 6 U2 22 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 JUN 13 PY 2001 VL 49 IS 10 BP 1701 EP 1715 DI 10.1016/S1359-6454(01)00087-8 PG 15 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 436YH UT WOS:000168963100003 ER PT J AU Benkovitz, CM Miller, MA Schwartz, SE Kwon, OU AF Benkovitz, CM Miller, MA Schwartz, SE Kwon, OU TI Dynamical influences on the distribution and loading of SO2 and sulfate over North America, the North Atlantic, and Europe in April 1987 SO GEOCHEMISTRY GEOPHYSICS GEOSYSTEMS LA English DT Article DE synoptic analysis; column burden; atmospheric model; cutoff low; middle atmosphere - composition and chemistry; middle atmosphere - constituent transport and; chemistry; troposphere - composition and chemistry; troposphere - constituent transport and chemistry ID ADVECTION SCHEME; GREENHOUSE GASES; MODEL; AEROSOLS; CLIMATOLOGY; TRENDS AB The loading of tropospheric aerosols is highly variable spatially and temporally as a consequences of large spatial variability in sources, temporal variability in transport winds, and short residence times (days), and additionally for secondary sulfate, intermittent production associated with aqueous-phase reaction in clouds, and intermittent removal, mainly by precipitation. We have used a chemical transport and transformation model for atmospheric sulfur driven by observationally derived meteorological data to calculate the geographical distribution of sulfate and sulfur dioxide (SO2) over North America, the North Atlantic, and Europe as a function of time for April 1987. We present the results of these calculations, mainly as animations showing the time dependence of the column burden (vertical integral of concentration) and of sulfate wet deposition, and interpret the temporal evolution in terms of the controlling meteorological phenomena as discerned from synoptic analyzes of 925 and 500 hPa. The analyzes show highly localized and episodic buildup and removal of sulfate and SO2 and circulations under the influence of high- and low-pressure systems as well as instances of rapid meridional and zonal transport over distances of thousands of kilometers. Key meteorological phenomena giving rise to large amounts of sulfate include not only slow moving high-pressure systems, as previously recognized, but also low-pressure systems. Whether or not a given low-pressure system results in large sulfate loading depends strongly on its location relative to sources of sulfur species and of the water vapor that is required for formation of clouds and precipitation. We present a detailed analysis of the evolution of sulfate and SO2 over the eastern North Atlantic April 3-8, 1987, under the influence of a cutoff low-pressure system during which sources in northern Europe continued to feed a system that repeatedly circulated over source regions. Animations such as these facilitate identification of episodes of large aerosol loading and relating these loadings to the controlling meteorological phenomena. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. Korea Meteorol Adm, Seoul, South Korea. RP Benkovitz, CM (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. RI Schwartz, Stephen/C-2729-2008 OI Schwartz, Stephen/0000-0001-6288-310X NR 35 TC 2 Z9 2 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 1525-2027 J9 GEOCHEM GEOPHY GEOSY JI Geochem. Geophys. Geosyst. PD JUN 13 PY 2001 VL 2 BP art. no. EP 2000gc000129 PG 32 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 458NR UT WOS:000170200900001 ER PT J AU Tang, RK Nancollas, GH Orme, CA AF Tang, RK Nancollas, GH Orme, CA TI Mechanism of dissolution of sparingly soluble electrolytes SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID ATOMIC-FORCE MICROSCOPY; CONSTANT UNDERSATURATION; PHOSPHATE CRYSTALS; GROWTH; KINETICS; CRYSTALLIZATION; SOLUBILITY AB Recent constant composition dissolution studies of sparingly soluble calcium phosphates have revealed an interesting and unusual behavior in that the rates decreased, eventually resulting in effective suppression, even though the solutions remained undersaturated. Contrary to traditional theories of dissolution, these experimental results indicated the importance of not only the particle size on the dissolution rate but also the participation of critical phenomena. In these theories, it is assumed that when the dissolution reactions are initiated, they continue spontaneously until all solid phase has disappeared. in terms of these mechanisms, there are no critical phenomena in the dissolution mechanism. Although the crystal size decreases during dissolution, when the reaction is controlled by polypitting (formation and growth of pits), the edge free energy increases at the very first stage due to the creation of pits and dissolution steps. The constant composition experimental results demonstrate the development of surface roughness as the dissolution steps are formed, implying an increase of the total edge length during the reactions. In an exactly analogous mechanism to crystal growth, the participation of critical conditions involving dissolution steps is a possibility. In contrast to crystal growth, dissolution is a process of size reduction and, when the particle size is sufficiently reduced, critical phenomena become important so that the influence of size must be taken into consideration. This paper proposes such a model for dissolution reactions, and although these unusual phenomena probably apply to all mineral phases, they are more evident for sparingly soluble electrolytes in which the critical conditions are attained much more readily. C1 SUNY Buffalo, Dept Chem, Buffalo, NY 14260 USA. Univ Calif Lawrence Livermore Natl Lab, Dept Chem & Mat Sci, Livermore, CA 94550 USA. RP Nancollas, GH (reprint author), SUNY Buffalo, Dept Chem, Nat Sci Complex, Buffalo, NY 14260 USA. RI Orme, Christine/A-4109-2009 FU NIDCR NIH HHS [DE03223] NR 58 TC 65 Z9 66 U1 2 U2 25 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 JUN 13 PY 2001 VL 123 IS 23 BP 5437 EP 5443 DI 10.1021/ja010064p PG 7 WC Chemistry, Multidisciplinary SC Chemistry GA 440LG UT WOS:000169176300009 PM 11389624 ER PT J AU Anxolabehere-Mallart, E Glaser, T Frank, P Aliverti, A Zanetti, G Hedman, B Hodgson, KO Solomon, EI AF Anxolabehere-Mallart, E Glaser, T Frank, P Aliverti, A Zanetti, G Hedman, B Hodgson, KO Solomon, EI TI Sulfur K-edge X-ray absorption spectroscopy of 2Fe-2S ferredoxin: Covalency of the oxidized and reduced 2Fe forms and comparison to model complexes SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID METAL-LIGAND COVALENCY; DIRECT ELECTROCHEMISTRY; ELECTRONIC-STRUCTURE; SPINACH FERREDOXIN; REDOX POTENTIALS; CLUSTERS; PROTEIN; SERIES; PURIFICATION; NITROGENASE AB Ligand K-edge X-ray absorption spectroscopy (XAS) provides a direct experimental probe of ligand-metal bonding. In previous studies, this method has been applied to mononuclear Fe-S and binuclear 2Fe-2S model compounds as well as to rubredoxins and the Rieske protein. These studies Lire now extended to the oxidized and reduced forms of ferredoxin I from spinach. Because of its high instability, the mixed-valence state was generated electrochemically in the protein matrix, and ligand K-edge absorption spectra were recorded using an XAS spectroelectrochemical cell. The experimental setup is described. The XAS edge data are analyzed to independently determine the covalencies of the iron-sulfide and -thiolate bonds. The results are compared with those obtained previously for the Rieske protein and for 2Fe-2S model compounds. It is found that the sulfide covalency is significantly lower in oxidized FdI compared to that of the oxidized model complex. This decrease is interpreted in terms of H bonding present in the protein, and its contribution to the reduction potential EO is estimated. Further, a significant increase in covalency for the Fe(III)-sulfide bond and a decrease of the Fe(II)-sulfide bond are observed in the reduced Fe(III)Fe(II) mixed-valence species compared to those of the Fe(III)Fe(III) homovalent site. This demonstrates that, upon reduction, the sulfide interactions with the ferrous site decrease, allowing greater charge donation to the remaining ferric center. That is the dominant change in electronic structure of the Fe2S2RS4 center upon reduction and can contribute to the redox properties of this active site. C1 Stanford Univ, Dept Chem, Stanford, CA 94305 USA. Stanford Univ, Stanford Linear Accelerator Ctr, Stanford Synchrotron Radiat Lab, Stanford, CA 94309 USA. Univ Milan, Dipartimento Fisiol & Biochim Gen, I-20133 Milan, Italy. RP Hedman, B (reprint author), Stanford Univ, Dept Chem, Stanford, CA 94305 USA. RI Glaser, Thorsten/H-5187-2013; Aliverti, Alessandro/B-7875-2017 OI Glaser, Thorsten/0000-0003-2056-7701; Aliverti, Alessandro/0000-0002-1226-3655 FU NCRR NIH HHS [RR-01209] NR 50 TC 38 Z9 38 U1 2 U2 9 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 JUN 13 PY 2001 VL 123 IS 23 BP 5444 EP 5452 DI 10.1021/ja010472t PG 9 WC Chemistry, Multidisciplinary SC Chemistry GA 440LG UT WOS:000169176300010 PM 11389625 ER EF