FN Thomson Reuters Web of Science™ VR 1.0 PT J AU Yang, IS Klein, MV Devereaux, TP Fisher, IR Canfield, PC AF Yang, IS Klein, MV Devereaux, TP Fisher, IR Canfield, PC TI Unconventional electronic Raman spectra of borocarbide superconductors SO PHYSICA C LA English DT Article; Proceedings Paper CT International Conference on Materials and Mechanisms of Superconductivity High Temperature Superconductors VI CY FEB 20-25, 2000 CL HOUSTON, TEXAS AB Borocarbide superconductors, which are thought to be conventional BCS-type superconductors, are not so conventional in several electronic Raman properties. Anisotropic gap-like features and finite scattering strength below the gap were observed for the RNi2B2C (R = Lu, Y) systems in our previous study.[1] The effects of Go-doping on the 2 Delta gap-like features and the finite scattering strength below and above the gap are studied in R = Lu (B = B-11) system. In superconducting states, Go-doping strongly suppresses the 2 Delta peak in both B-2g and B-1g symmetries. Raman cross-section calculation which includes inelastic scattering shows a relatively good fit to the features above the 2 Delta peak, while it does not fully account for the features below the peak. C1 Ewha Womans Univ, Dept Phys, Seoul 120750, South Korea. Univ Illinois, Sci & Technol Ctr Superconduct, Urbana, IL 61801 USA. Univ Illinois, Dept Phys, Urbana, IL 61801 USA. Univ Waterloo, Dept Phys, Waterloo, ON N2L 3G1, Canada. Iowa State Univ, Dept Phys & Astron, Ames Lab, Ames, IA 50011 USA. RP Yang, IS (reprint author), Ewha Womans Univ, Dept Phys, Seoul 120750, South Korea. RI Canfield, Paul/H-2698-2014 NR 8 TC 3 Z9 3 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 NOV PY 2000 VL 341 BP 2259 EP 2260 DI 10.1016/S0921-4534(00)01106-0 PN 4 PG 2 WC Physics, Applied SC Physics GA 382YY UT WOS:000165856000075 ER PT J AU Foltyn, SR Arendt, PN DePaula, RF Dowden, PC Coulter, JY Groves, JR Haussamen, LN Winston, LP Jia, QX Maley, MP AF Foltyn, SR Arendt, PN DePaula, RF Dowden, PC Coulter, JY Groves, JR Haussamen, LN Winston, LP Jia, QX Maley, MP TI Development of meter-long YBCO coated conductors produced by ion beam assisted deposition and pulsed laser deposition SO PHYSICA C LA English DT Article; Proceedings Paper CT International Conference on Materials and Mechanisms of Superconductivity High Temperature Superconductors VI CY FEB 20-25, 2000 CL HOUSTON, TEXAS ID YBA2CU3O7-DELTA THICK-FILMS; ANISOTROPY; ALLOY AB A "second-generation" of high T-c conductors, consisting of YBCO coatings on flexible metal substrates, has recently reached a milestone with meter-long tapes capable of carrying over 100 A in a 1 cm width at liquid nitrogen temperature. Having reached this level of performance, however, we have encountered difficulties in the self-field characterization of such high current material. In particular, measurement of critical current uniformity along the tape length has in Some cases resulted in damage to weaker tape segments during measurement of higher-current ones. To address this problem we have developed a novel measurement technique that uses permanent magnets to locally suppress the critical current of the tape section being measured to a level that is "safe" for the rest of the tape. C1 Univ Calif Los Alamos Natl Lab, Superconduct Technol Ctr, Los Alamos, NM 87545 USA. RP Foltyn, SR (reprint author), Univ Calif Los Alamos Natl Lab, Superconduct Technol Ctr, POB 1663, Los Alamos, NM 87545 USA. RI Jia, Q. X./C-5194-2008 NR 8 TC 27 Z9 27 U1 1 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD NOV PY 2000 VL 341 BP 2305 EP 2308 DI 10.1016/S0921-4534(00)01020-0 PN 4 PG 4 WC Physics, Applied SC Physics GA 382YY UT WOS:000165856000090 ER PT J AU Annavarapu, S Fritzemeier, L Li, Q Malozemoff, A Prunier, V Rupich, MW Thieme, C Zhang, W Gopal, M Seleznev, I Cima, MJ Paranthaman, M Goyal, A Lee, DF AF Annavarapu, S Fritzemeier, L Li, Q Malozemoff, A Prunier, V Rupich, MW Thieme, C Zhang, W Gopal, M Seleznev, I Cima, MJ Paranthaman, M Goyal, A Lee, DF TI Progress towards a low-cost coated conductor technology SO PHYSICA C LA English DT Article; Proceedings Paper CT International Conference on Materials and Mechanisms of Superconductivity High Temperature Superconductors VI CY FEB 20-25, 2000 CL HOUSTON, TEXAS ID BUFFER LAYERS; GROWTH; EVAPORATION; TAPES AB Progress in the development of an economically and technically viable YBCO coated conductor technology for HTS wire using deformation-textured buffered substrates and solution-deposited superconductor layers is reported. Biaxially textured Ni substrates have been fabricated using a deformation texturing process. Epitaxial oxide buffer layers have been deposited by a combination of a-beam deposition and magnetron sputtering. Epitaxial YBCO films have been grown using a trifluoroacetate solution precursor. The resulting composite conductors have critical current densities approaching 2 MA/cm(2) at 77K in self-field. Critical current densities of 4.5 MA/cm(2) have been also obtained on CeO2 buffered YSZ single crystal substrates, demonstrating performance parity with vacuum deposited YBCO films. C1 Amer Superconductor, Res & Dev, Westborough, MA 01581 USA. MIT, Ceram Proc Lab, Cambridge, MA 02139 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Annavarapu, S (reprint author), Amer Superconductor, Res & Dev, 2 Technol Dr, Westborough, MA 01581 USA. RI Paranthaman, Mariappan/N-3866-2015 OI Paranthaman, Mariappan/0000-0003-3009-8531 NR 13 TC 7 Z9 7 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 NOV PY 2000 VL 341 BP 2319 EP 2322 DI 10.1016/S0921-4534(00)01038-8 PN 4 PG 4 WC Physics, Applied SC Physics GA 382YY UT WOS:000165856000093 ER PT J AU Athur, SP Balachandran, U Salama, K AF Athur, SP Balachandran, U Salama, K TI Melt-processing of Yb-123 tapes SO PHYSICA C LA English DT Article; Proceedings Paper CT International Conference on Materials and Mechanisms of Superconductivity High Temperature Superconductors VI CY FEB 20-25, 2000 CL HOUSTON, TEXAS ID CURRENT DENSITY; THICK-FILMS; SUPERCONDUCTOR AB The innovation of a simple, scalable process for manufacturing long-length conductors of HTS is essential to potential commercial applications such as power cables, magnets, and transformers. In this paper we demonstrate that melt processing of Yb-123 tapes made by the PIT route is an alternative to the coated conductor and Bi-2223 PIT tape fabrication techniques. Ag-clad Yb-123 tapes were fabricated by groove rolling and subsequently, melt processed in different oxygen partial pressures in a zone-melting furnace with a gradient of 140 degreesC/cm. The transition temperatures measured were found to be around 81 K under most processing conditions. EPMA of the tapes processed under different conditions show the 123 phase to be Pa deficient and Cu and Yb rich. Critical current was measured at various temperatures from 77 K to 4.2 K. The J(c) increased with decrease in pO(2). The highest I, obtained was 52 A at 4.2 K. C1 Univ Houston, Texas Ctr Superconduct, Houston, TX 77204 USA. Argonne Natl Lab, Div Energy Technol, Argonne, IL 60439 USA. RP Athur, SP (reprint author), Univ Houston, Texas Ctr Superconduct, Houston, TX 77204 USA. NR 8 TC 1 Z9 1 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD NOV PY 2000 VL 341 BP 2421 EP 2424 DI 10.1016/S0921-4534(00)01142-4 PN 4 PG 4 WC Physics, Applied SC Physics GA 382YY UT WOS:000165856000137 ER PT J AU Park, C Norton, DP Lee, DF Verebelyi, DT Goyal, A Christen, DK Budai, JD AF Park, C Norton, DP Lee, DF Verebelyi, DT Goyal, A Christen, DK Budai, JD TI Epitaxial yttria-stabilized zirconia on biaxially-textured (001) Ni for YBCO coated conductor SO PHYSICA C LA English DT Article; Proceedings Paper CT International Conference on Materials and Mechanisms of Superconductivity High Temperature Superconductors VI CY FEB 20-25, 2000 CL HOUSTON, TEXAS ID YBA2CU3O7 AB Epitaxial YSZ film was deposited directly on biaxially-textured (001) Mi tapes using pulsed-laser deposition. Nucleation of the YSZ film on Wi is achieved without the intentional removal of the native oxide from the Mi (001) surface. The epitaxial YSZ layer grown on the Wi (001) surface was used as a single buffer layer for a high temperature superconducting coated conductor architecture, yielding YBa2Cu3O7 films with critical current density of 1 MA/cm(2) at 77 K. This architecture eliminates the necessity for a multilayer buffer architecture, as high J(c) superconducting films are achieved with no intermediate buffer layer between the (001) YSZ and the biaxially textured metal. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Park, C (reprint author), Oak Ridge Natl Lab, POB 2008,MS-6056, Oak Ridge, TN 37831 USA. RI Yoon, Sejin/F-7637-2013; Budai, John/R-9276-2016 OI Budai, John/0000-0002-7444-1306 NR 4 TC 11 Z9 11 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD NOV PY 2000 VL 341 BP 2481 EP 2482 DI 10.1016/S0921-4534(00)01199-0 PN 4 PG 2 WC Physics, Applied SC Physics GA 382YY UT WOS:000165856000166 ER PT J AU Chudzik, MP Erck, RA Luo, ZP Miller, DJ Balachandran, U Kannewurf, CR AF Chudzik, MP Erck, RA Luo, ZP Miller, DJ Balachandran, U Kannewurf, CR TI High-rate reel-to-reel continuous coating of biaxially textured magnesium oxide thin films for coated conductors SO PHYSICA C LA English DT Article; Proceedings Paper CT International Conference on Materials and Mechanisms of Superconductivity High Temperature Superconductors VI CY FEB 20-25, 2000 CL HOUSTON, TEXAS AB Biaxially textured thin films of magnesium oxide (MgO) were deposited by electron beam evaporation at deposition rates of 0.6 mum/min on moving Ni-based alloy tapes as oriented buffer layers for coated conductors. Moving substrates were inclined with respect to the atomic vapor and translated through collimated dual vapor sources. Growth anisotropy in the MgO and sell-shadowing effects due to the inclined angle combine to create biaxial texture in the deposited thin films. MgO films grown to a thickness of 2.0 mum with this inclined-substrate deposition technique have yielded in-plane textures of 10-12 degrees full-width half-maximum (FWHM). Results of a parametric study on the in-plane texture in short-length static-mode samples are presented, along with preliminary results of long-length samples deposited under translating conditions. C1 Northwestern Univ, Dept Elect & Comp Engn, Evanston, IL 60208 USA. Argonne Natl Lab, Div Energy Technol, Argonne, IL 60439 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Chudzik, MP (reprint author), Northwestern Univ, Dept Elect & Comp Engn, Evanston, IL 60208 USA. RI Luo, Zhiping/C-4435-2014 OI Luo, Zhiping/0000-0002-8264-6424 NR 1 TC 6 Z9 6 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD NOV PY 2000 VL 341 BP 2483 EP 2484 DI 10.1016/S0921-4534(00)01267-3 PN 4 PG 2 WC Physics, Applied SC Physics GA 382YY UT WOS:000165856000167 ER PT J AU Brown, GW Hawley, ME Brown, DJ Mueller, FM AF Brown, GW Hawley, ME Brown, DJ Mueller, FM TI Magnetic imaging of superconducting tapes to determine current flow SO PHYSICA C LA English DT Article; Proceedings Paper CT International Conference on Materials and Mechanisms of Superconductivity High Temperature Superconductors VI CY FEB 20-25, 2000 CL HOUSTON, TEXAS ID SCANNING MAGNETORESISTANCE MICROSCOPY; FILMS AB We have developed a magnetic imaging system that yields quantitative information about the magnetic field near the surface of a superconducting sample while it is carrying current at liquid nitrogen temperatures. We have numerically inverted the external magnetic field data from YBa2Cu3O7-delta bridges and silver-coated YBa2CU3O7-delta tapes to derive the internal current densities. Preliminary results are consistent with the expected patterns but suggest that the current flow is non-uniform. C1 Univ Calif Los Alamos Natl Lab, Los Alamos Neutron Sci Ctr LANSCE 9, Los Alamos, NM 87545 USA. Univ Calif Los Alamos Natl Lab, Superconduct Technol Ctr, Los Alamos, NM 87545 USA. RP Brown, GW (reprint author), Univ Calif Los Alamos Natl Lab, Los Alamos Neutron Sci Ctr LANSCE 9, POB 1663, Los Alamos, NM 87545 USA. NR 6 TC 1 Z9 1 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 NOV PY 2000 VL 341 BP 2497 EP 2498 DI 10.1016/S0921-4534(00)01289-2 PN 4 PG 2 WC Physics, Applied SC Physics GA 382YY UT WOS:000165856000174 ER PT J AU Xie, YY Aytug, T Wu, JZ Verebelyi, DT Christen, DK AF Xie, YY Aytug, T Wu, JZ Verebelyi, DT Christen, DK TI Growth and physical properties of Hg-1212HTSC tapes on buffered metal substrates SO PHYSICA C LA English DT Article; Proceedings Paper CT International Conference on Materials and Mechanisms of Superconductivity High Temperature Superconductors VI CY FEB 20-25, 2000 CL HOUSTON, TEXAS ID THIN-FILMS; TEMPERATURE AB Fast Temperature Ramping Annealing (FTRA:) combined with a cation-exchange process is applied in the fabrication of HgBa2Ca1Cu2Ox (Hg-1212) superconducting tapes on Rolling Assisted Biaxially Textured Substrates (RABiTSs). Tl2Ba2CaCu2Ox (Tl-2212:) precursor films were synthesized on RABiTSs and then converted into Hg-1212 films. By employing the FTRA process in the synthesis of Tl-2212 films, significant improvement was achieved in terms of surface morphology as well as in-plane alignment. These features were retained in the Hg-1212 films during Tl-Hg cation-exchange. T-c of Hg-12.12 films is up to 124K and J(c) is up to 10(5)A/cm(2) (OT) at 115K. Further improvements in J(c) are expected for optimized synthesis conditions. C1 Univ Kansas, Dept Phys & Astron, Lawrence, KS 66045 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Xie, YY (reprint author), Univ Kansas, Dept Phys & Astron, Lawrence, KS 66045 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 0921-4534 J9 PHYSICA C JI Physica C PD NOV PY 2000 VL 341 BP 2505 EP 2506 DI 10.1016/S0921-4534(00)01296-X PN 4 PG 2 WC Physics, Applied SC Physics GA 382YY UT WOS:000165856000178 ER PT J AU Motowidlo, LR Sokolowski, RS Hasegawa, T Aoki, Y Koizumi, T Ohtani, N Scanlan, R Dietderich, D Nagaya, S AF Motowidlo, LR Sokolowski, RS Hasegawa, T Aoki, Y Koizumi, T Ohtani, N Scanlan, R Dietderich, D Nagaya, S TI Development of Bi-2212 Rutherford cable SO PHYSICA C LA English DT Article; Proceedings Paper CT International Conference on Materials and Mechanisms of Superconductivity High Temperature Superconductors VI CY FEB 20-25, 2000 CL HOUSTON, TEXAS AB An 80 meter long Rutherford cable was fabricated with 20 strands of 0.8 mm diameter Bi-2212 wire. The conductor utilized in this cable was a double stack design (7 X 61) comprising 427 filaments. The critical current (Ic) of the cable was measured at liquid helium in applied magnetic field up to 4T. The Ic results of the cable show no degradation when normalized to the strand. The cable was sectioned into four 17-meter lengths and one 10-meter piece. These sections were heat treated and the ends cut and tested. The average Ic of all cable pieces tested was 2990 A +/- 10% in self field. The bending strain of Rutherford cables with a ceramic coated Ni-alloy core showed little or no degradation up to 6%. In contrast, cables manufactured without a Ni-alloy core showed critical bending strains of about 2%. C1 IGC Adv Superconductors, Waterbury, CT 06704 USA. Showa Elect Wire & Cable, Kawasaki, Kanagawa 210, Japan. Lawrence Berkeley Natl Lab, Berkeley, CA 94707 USA. Chubu Elect, Nagoya, Aichi, Japan. RP Motowidlo, LR (reprint author), IGC Adv Superconductors, Waterbury, CT 06704 USA. NR 5 TC 3 Z9 3 U1 1 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD NOV PY 2000 VL 341 BP 2539 EP 2543 DI 10.1016/S0921-4534(00)01344-7 PN 4 PG 5 WC Physics, Applied SC Physics GA 382YY UT WOS:000165856000187 ER PT J AU Dietderich, DR Hasegawa, T Aoki, Y Scanlan, RM AF Dietderich, DR Hasegawa, T Aoki, Y Scanlan, RM TI Critical current variation of Rutherford cable of Bi-2212 in high magnetic fields with transverse stress SO PHYSICA C LA English DT Article; Proceedings Paper CT International Conference on Materials and Mechanisms of Superconductivity High Temperature Superconductors VI CY FEB 20-25, 2000 CL HOUSTON, TEXAS AB For numerous high-energy physics applications superconducting cables are subjected to large stresses and high magnetic fields during service. It is essential to know how cables perform in these operating conditions. Transverse loading experiments on wire has shown that a significant drop in critical current occurs for stresses greater than 50 MPa. However, many applications require that the Bi-2212 conductor withstand stresses greater than 100 MPa without permanent degradation. Therefore, a study of epoxy impregnated cables, identical to those used in accelerator magnet applications, has been performed. This work presents the first results of Rutherford cables of Bi-2212 with transverse stress. The results show that the cable can withstand stresses up to 60 MPa with a strain of about 0.3 % for the face loading orientation and 100 MPa for the edge loading orientation. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Showa Elect Wire & Cable Co Ltd, Kawasaki, Kanagawa, Japan. RP Dietderich, DR (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, 1 Cyclotron Rd, Berkeley, CA 94720 USA. NR 5 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 NOV PY 2000 VL 341 BP 2599 EP 2600 DI 10.1016/S0921-4534(00)01371-X PN 4 PG 2 WC Physics, Applied SC Physics GA 382YY UT WOS:000165856000209 ER PT J AU Helm, C Odagawa, A Sakai, M Adachi, H Setsune, K Kleiner, R AF Helm, C Odagawa, A Sakai, M Adachi, H Setsune, K Kleiner, R TI Interpretation of a microwave induced current step in a single intrinsic Josephson junction on a Bi-2223 thin film SO PHYSICA C LA English DT Article; Proceedings Paper CT International Conference on Materials and Mechanisms of Superconductivity High Temperature Superconductors VI CY FEB 20-25, 2000 CL HOUSTON, TEXAS ID CUPRATE SUPERCONDUCTORS; BI2SR2CACU2O8+DELTA; CRYSTALS; PLASMA AB Thin stacks consisting of a single intrinsic Josephson junction on (Bi,Pb)-Sr-Ca-Cn-O thin films are investigated under the influence of external microwave fields. The I-V-characteristic shows a single resistive branch, a clear superconducting gal, edge structure and a pronounced current step in external microwave fields. With increasing irradiation power it shifts to higher voltages, while the height of the step remains practically unchanged. In a numerical simulation including an ac-magnetic field parallel to the superconducting layers the experimental features of the structure can he explained by a. collective motion of Josephson fluxons. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Regensburg, Inst Theoret Phys, D-93040 Regensburg, Germany. Matsushita Elect Ind Co Ltd, Adv Technol Res Lab, Kyoto 6190237, Japan. Univ Tubingen, Lehrstuhl Expt Phys 2, Inst Phys, D-72076 Tubingen, Germany. RP Helm, C (reprint author), Univ Calif Los Alamos Natl Lab, T-11,MS B-262, Los Alamos, NM 87545 USA. NR 13 TC 2 Z9 2 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD NOV PY 2000 VL 341 BP 2645 EP 2648 DI 10.1016/S0921-4534(00)01435-0 PN 4 PG 4 WC Physics, Applied SC Physics GA 382YY UT WOS:000165856000231 ER PT J AU Huang, ZB Lin, HQ Gubernatis, JE AF Huang, ZB Lin, HQ Gubernatis, JE TI Influence of intersite Cu-O repulsion on hole binding and pairing correlations in the three-band Hubbard model SO PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS LA English DT Article; Proceedings Paper CT International Conference on Materials and Mechanisms of Superconductivity High Temperature Superconductors VI CY FEB 20-25, 2000 CL HOUSTON, TX ID MONTE-CARLO AB The hole binding energy and pairing correlations are calculated in the three-band Hubbard model by using the constrained-path Monte Carlo (CPMC) method. In the physically relevant region, we investigated effects of Ca - O Coulomb repulsion V-pd on these two properties. Simulations were performed on lattices of 2x2, 4x2, and 6x4 unit cells. For the 2x2 unit cell, the CPMC results are in good agreement with exact diagonalization results. For it we found that the hole binding energy clearly increases with the nearest-neighbor Coulomb repulsion Vpd, but for larger systems it increases only slightly. For the:extended s-wave channel, we found that the pairing correlations and vertex contributions increase slightly with an increase of V-pd, while for the d(x2-y2)-wave channel both tend to decrease. C1 Chinese Univ Hong Kong, Dept Phys, Hong Kong, Hong Kong, Peoples R China. Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Huang, ZB (reprint author), Chinese Univ Hong Kong, Dept Phys, Hong Kong, Hong Kong, Peoples R China. NR 6 TC 0 Z9 0 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD NOV PY 2000 VL 341 BP 243 EP 244 DI 10.1016/S0921-4534(00)00461-5 PN 1 PG 2 WC Physics, Applied SC Physics GA 382YT UT WOS:000165855500078 ER PT J AU Crabtree, GW Lopez, D Kwok, WK Safar, H Paulius, LM AF Crabtree, GW Lopez, D Kwok, WK Safar, H Paulius, LM TI Dynamic correlation in vortex liquids and solids SO PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS LA English DT Article; Proceedings Paper CT International Conference on Materials and Mechanisms of Superconductivity High Temperature Superconductors VI CY FEB 20-25, 2000 CL HOUSTON, TX ID HIGH-TEMPERATURE SUPERCONDUCTORS; LATTICE-MELTING TRANSITION; OXYGEN DEFICIENCY; YBA2CU3O7-DELTA; HYDRODYNAMICS; SYSTEM; LINE AB The velocity profile of vortices driven by a non-uniform Lorentz force contains information on the dynamic correlation of the moving liquid, lattice, and glassy phases. We describe transport experiments using a disk geometry that allow the velocity profile to be measured and analyzed in terms of the hydrodynamic motion of the liquid, and the plastic and elastic motion of the solid. Application to the glassy states bordering the upper and lower critical points is discussed. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Univ Illinois, Dept Phys, Chicago, IL 60680 USA. Western Michigan Univ, Dept Phys, Kalamazoo, MI 49008 USA. RP Crabtree, GW (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 18 TC 1 Z9 1 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD NOV PY 2000 VL 341 BP 995 EP 998 DI 10.1016/S0921-4534(00)00761-9 PN 2 PG 4 WC Physics, Applied SC Physics GA 382YV UT WOS:000165855700108 ER PT J AU Kolesnik, S Vlasko-Vlasov, V Welp, U Crabtree, GW Piotrowski, T Wrobel, J Klimov, A Przyslupski, P Skoskiewicz, T Dabrowski, B AF Kolesnik, S Vlasko-Vlasov, V Welp, U Crabtree, GW Piotrowski, T Wrobel, J Klimov, A Przyslupski, P Skoskiewicz, T Dabrowski, B TI Flux pinning by anisotropic arrays of antidots in superconducting thin films SO PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS LA English DT Article; Proceedings Paper CT International Conference on Materials and Mechanisms of Superconductivity High Temperature Superconductors VI CY FEB 20-25, 2000 CL HOUSTON, TX ID MAGNETIC DOTS; LATTICE AB Anisotropic arrays of antidots have been prepared on Y-Ba-Cu-O and Nb thin films by electron-beam lithography. Fast-Fourier-Transform analysis of the magnetization curves for Y-Ba-Cu-O thin film reveals their periodical character which corresponds to the matching effect of the vortex lattice. For niobium thin film, matching peaks can be observed on the decreasing branches of the magnetization curves. Magneto-optical investigations at lower temperatures show unidirectional Aux entry and exit along the shorter antidot lattice parameter. In higher magnetic fields, an anisotropic critical state is observed. Our observations strongly suggest formation of anisotropic vortex lattices in the patterned thin films. C1 Polish Acad Sci, Inst Phys, PL-02668 Warsaw, Poland. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Inst Electr Mat Technol, PL-02668 Warsaw, Poland. No Illinois Univ, Dept Phys, De Kalb, IL 60115 USA. RP Kolesnik, S (reprint author), Polish Acad Sci, Inst Phys, Al Lotnikow 32-46, PL-02668 Warsaw, Poland. RI Wrobel, Jerzy/G-8042-2014; piotr, Przyslupski/L-2957-2016 NR 5 TC 13 Z9 13 U1 1 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 NOV PY 2000 VL 341 BP 1093 EP 1094 DI 10.1016/S0921-4534(00)00799-1 PN 2 PG 2 WC Physics, Applied SC Physics GA 382YV UT WOS:000165855700146 ER PT J AU Wang, YM Zettl, A Tamegai, T Ooi, S AF Wang, YM Zettl, A Tamegai, T Ooi, S TI Sample size dependence of vortex penetration and the second magnetization peak in Bi2Sr2CaCu2O8+delta SO PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS LA English DT Article; Proceedings Paper CT International Conference on Materials and Mechanisms of Superconductivity High Temperature Superconductors VI CY FEB 20-25, 2000 CL HOUSTON, TX ID BARRIERS AB Local magnetization measurements of Bi2Sr2CaCu2O8+delta single crystals with various shape and size were performed using a local GaAs/AlGaAs Hall probe. The vortex penetration field is proportional to the -1/4 power of the sample area, independent of sample geometry. The second magnetization peak (SMP) is observed only below a size dependent temperature, which may not support the 2D-3D vortex solid transition as the intrinsic origin of the SMP. C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Lawrence Berkeley Natl Lab, Div Sci Mat, Berkeley, CA 94720 USA. Univ Tokyo, Dept Appl Phys, Bunkyo Ku, Tokyo 1138656, Japan. RP Wang, YM (reprint author), Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. RI Tamegai, Tsuyoshi /C-6656-2011; Zettl, Alex/O-4925-2016 OI Zettl, Alex/0000-0001-6330-136X NR 5 TC 5 Z9 5 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD NOV PY 2000 VL 341 BP 1109 EP 1110 DI 10.1016/S0921-4534(00)00807-8 PN 2 PG 2 WC Physics, Applied SC Physics GA 382YV UT WOS:000165855700154 ER PT J AU Vlasko-Vlasov, V Welp, U Metlushko, V Crabtree, GW AF Vlasko-Vlasov, V Welp, U Metlushko, V Crabtree, GW TI Flux avalanches in superconducting films with periodic arrays of holes SO PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS LA English DT Article; Proceedings Paper CT International Conference on Materials and Mechanisms of Superconductivity High Temperature Superconductors VI CY FEB 20-25, 2000 CL HOUSTON, TX AB The magnetic Aux dynamics in Nh films with periodic hole arrays is studied magneto-optically. Flux motion in the shape of microavalanches along {100} and {110} directions of the hole lattice is observed. At lower temperatures anisotropic large scale thermo-magnetic avalanches dominate flux entry and exit. At T similar to T-C critical-state-like field patterns periodically appear at fractions of the matching field. C1 Argonne Natl Lab, Argonne, IL 60439 USA. Russian Acad Sci, Inst Solid State Phys, Chernogolovka 142432, Russia. RP Argonne Natl Lab, MSD223,9700 S Cass Ave, Argonne, IL 60439 USA. NR 6 TC 32 Z9 32 U1 0 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 EI 1873-2143 J9 PHYSICA C JI Physica C PD NOV PY 2000 VL 341 BP 1281 EP 1282 DI 10.1016/S0921-4534(00)00895-9 PN 2 PG 2 WC Physics, Applied SC Physics GA 382YV UT WOS:000165855700240 ER PT J AU Li, Q Tsay, YN Zhu, Y Suenaga, M Gu, GD Koshizuka, N AF Li, Q Tsay, YN Zhu, Y Suenaga, M Gu, GD Koshizuka, N TI Electromagnetic and microstructural properties of bulk bicrystal grain boundaries in Bi2Sr2CaCu2O8+delta superconductors SO PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS LA English DT Article; Proceedings Paper CT International Conference on Materials and Mechanisms of Superconductivity High Temperature Superconductors VI CY FEB 20-25, 2000 CL HOUSTON, TX ID MISORIENTATION AB We present systematic studies of electromagnetic and microstructural properties of bulk Bi2Sr2CaCu2O8+delta (Bi2212) bicrystals having synthetic [001] twist or naturally-grown [100] tilt boundaries. We find that [001] twist boundaries in as-prepared bicrystals, regardless of twist angles, conduct virtually the same critical current I-c as the constituent single crystals. We also irradiated some of the [001] twist bicrystals with 2.2 GeV Au-ions, and found that the [001] twist grain boundaries carry significantly less critical current than the irradiated single crystals in magnetic field. For naturally grown [100] tilt boundaries, we find a general T-c depression by several degrees at the grain boundary. Strong coupling behavior was observed in several high angle tilt grain boundaries below the grain boundary T-c(Gb). C1 Brookhaven Natl Lab, Dept Appl Sci, Upton, NY 11973 USA. ISTEC, Superconduct Res Lab, Tokyo 135, Japan. RP Brookhaven Natl Lab, Dept Appl Sci, Upton, NY 11973 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 EI 1873-2143 J9 PHYSICA C JI Physica C PD NOV PY 2000 VL 341 BP 1407 EP 1410 DI 10.1016/S0921-4534(00)00959-X PN 3 PG 4 WC Physics, Applied SC Physics GA 382YX UT WOS:000165855900004 ER PT J AU Moodenbaugh, AR Cox, DE AF Moodenbaugh, AR Cox, DE TI Low temperature x-ray diffraction study of La2-xMxCuO4, M=Ba, Sr SO PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS LA English DT Article; Proceedings Paper CT International Conference on Materials and Mechanisms of Superconductivity High Temperature Superconductors VI CY FEB 20-25, 2000 CL HOUSTON, TX ID LA2-XBAXCUO4; SUPERCONDUCTIVITY; TRANSITION AB The low temperature phase diagrams for La2-xMxCuO4, M=Ba and Sr. were redetermined using high resolution synchrotron x-ray diffraction, by monitoring the low temperature orthorhombic (LTO1, standard space group Cmca indexed Bmab) 020/200 and low temperature tetragonal (LTT, P4(2)/ncm) 200 peaks. For M=Ba, the LTT phase exists as a minority phase at the 10-15% level in the nominally LTO1 phase well above the bulk LTT transformation temperature. For M=Sr there is no bulk LTT transformation, but up to 10% LTT phase is observed at low temperatures. For unsubstituted La2CuO4 no LTT contribution to diffraction is observed, down to an estimated sensitivity of 3%. For x>0.12, both for M=Sr and Ba, the LTO1 200/020 diffraction peak splitting at low temperatures is inadequate to allow the observation of a possible minority LTT phase. Based on low temperature transmission electron microscopy studies of La2-xBaxCuO4, we propose a two step transformation from the LTO1 to the LTT phase. The LTT phase may be nucleated at relatively high temperatures at the LTO1 twin boundaries. For M=Ba, near T=60 K, the LTT phase also develops within the LTO1 twins, and the sample essentially completely transforms to LTT. C1 Brookhaven Natl Lab, Dept Appl Sci, Upton, NY 11973 USA. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Moodenbaugh, AR (reprint author), Brookhaven Natl Lab, Dept Appl Sci, Upton, NY 11973 USA. OI Moodenbaugh, Arnold/0000-0002-3415-6762 NR 11 TC 3 Z9 3 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 NOV PY 2000 VL 341 BP 1775 EP 1778 DI 10.1016/S0921-4534(00)01028-5 PN 3 PG 4 WC Physics, Applied SC Physics GA 382YX UT WOS:000165855900131 ER PT J AU Liu, HL Blumberg, G Klein, MV Guptasarma, P Hinks, DG AF Liu, HL Blumberg, G Klein, MV Guptasarma, P Hinks, DG TI Electronic Raman scattering in Bi2Sr2CaCu2O8+delta excited with c-axis polarized light SO PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS LA English DT Article; Proceedings Paper CT International Conference on Materials and Mechanisms of Superconductivity High Temperature Superconductors VI CY FEB 20-25, 2000 CL HOUSTON, TX ID SUPERCONDUCTING GAP ANISOTROPY; COPPER-OXIDE SUPERCONDUCTORS; SINGLE-CRYSTALS; ELECTRODYNAMICS; SPECTROSCOPY; SPECTRA; PHONONS AB We report on the electronic Raman spectra ex:cited and detected with photon polarization directions along the c-axis in Bi2Sr2CaCu2O8+delta single crystals. In the normal state, a resonant electronic continuum extends to 1.5 eV and gains significant intensity as the incoming photon energy increases. Below T-c, there is a low-frequency redistribution of the electronic continuum and the formation of a 2 Delta peak in the superconducting state. The monotonic increase of 2 Delta and 2 Delta /k(B)T(c) with decreasing doping is unusual. In particular, this 2 Delta feature, which has A(1g) symmetry, is found at higher frequencies than those seen in the planar symmetries for all doping levels studied. C1 Univ Illinois, Dept Phys, Urbana, IL 61801 USA. Univ Illinois, Sci & Technol Ctr Superconduct, Urbana, IL 61801 USA. Natl Taiwan Normal Univ, Dept Phys, Taipei 116, Taiwan. Lucent Technol, Bell Labs, Murray Hill, NJ 07974 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Argonne Natl Lab, Sci & Technol Ctr Superconduct, Argonne, IL 60439 USA. Univ Wisconsin, Dept Phys, Milwaukee, WI 53211 USA. RP Univ Illinois, Dept Phys, Urbana, IL 61801 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 0921-4534 EI 1873-2143 J9 PHYSICA C JI Physica C PD NOV PY 2000 VL 341 BP 2181 EP 2184 DI 10.1016/S0921-4534(00)01262-4 PN 4 PG 4 WC Physics, Applied SC Physics GA 382YY UT WOS:000165856000045 ER PT J AU Istratov, AA Flink, C Weber, ER AF Istratov, AA Flink, C Weber, ER TI Impact of the unique physical properties of copper in silicon on characterization of copper diffusion barriers SO PHYSICA STATUS SOLIDI B-BASIC RESEARCH LA English DT Review ID RESONANCE PLASMA NITRIDATION; ROOM-TEMPERATURE OXIDATION; REACTIVELY SPUTTERED TIN; TRANSIENT ION-DRIFT; CU-DIFFUSION; ELECTRICAL CHARACTERIZATION; THERMAL-STABILITY; METAL IMPURITIES; LEAKAGE CURRENT; METALLIZATION AB In this paper, we establish a connection between the physical properties of copper in silicon substrates and the problems of characterization of copper diffusion barriers for ultra-large scale integration (ULSI) technology. We show that many of the methods successfully used for detection of the failure of aluminum diffusion barriers are poorly suited for characterization of barriers for copper metallization technology. This is because the unique physical properties of copper make its diffusion and precipitation behavior in silicon significantly different from those of other metals. These properties must be taken into account in studies of the detrimental effect of copper on device yield and in development of thin diffusion barriers for copper metallization. The sensitivity of most depth profiling techniques (such as secondary ion mass spectrometry, Auger electron spectroscopy, or Rutherford backscattering) is not sufficient to detect barrier failure before the dissolved copper concentration in the bulk reaches its solubility limit at the back-end processing temperature (e.g., 2 x 10(13) cm(-3) at 450 degreesC). The electrical measurement techniques, such as analysis of I-V characteristics of p-n junctions formed by ion implantation under the barrier layers are more sensitive to penetration of copper than depth profiling techniques, but cannot determine the copper contamination level quantitatively. Emerging tools suitable for detection of copper penetration at technologically relevant levels are discussed. C1 Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Mat Sci & Engn, Berkeley, CA 94720 USA. RP Istratov, AA (reprint author), Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Mail Stop 62-203,1 Cyclotron Rd, Berkeley, CA 94720 USA. NR 109 TC 16 Z9 16 U1 1 U2 10 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 NOV PY 2000 VL 222 IS 1 BP 261 EP 277 DI 10.1002/1521-3951(200011)222:1<261::AID-PSSB261>3.0.CO;2-5 PG 17 WC Physics, Condensed Matter SC Physics GA 382KU UT WOS:000165822100025 ER PT J AU Cheng, KT Chen, MH Sapirstein, J AF Cheng, KT Chen, MH Sapirstein, J TI Quantum electrodynamic corrections in high-Z Li-like and Be-like ions SO PHYSICAL REVIEW A LA English DT Article ID CONFIGURATION-INTERACTION CALCULATIONS; PERTURBATION-THEORY CALCULATIONS; LAMB-SHIFT CALCULATIONS; TRANSITION ENERGIES; POLARIZATION CONTRIBUTION; 2S(1/2)-2P(3/2) LEVELS; VACUUM POLARIZATION; URANIUM IONS; SELF-ENERGY; STATES AB Relativistic configuration-interaction (RCI) calculations of the correlation energies of the 2s-2p(3/2) and the 2s(2) S-1(0) - 2s2p P-1(1) transitions in high-Z Li-like and Be-like ions, respectively, are reexamined. Experimental quantum electrodynamic (QED) corrections are obtained by subtracting RCI correlation energies from high-precision x-ray energy measurements, It is found that our QED results are in good agreement with experiment and that screening and relaxation corrections are well accounted for by the use of the Dirac-Kohn-Sham potentials in QED calculations of the one-loop radiative diagrams. Our present QED energies are also in good agreement with recent higher-order QED calculations of the 2s-2p(1/2) transition in high-Z Li-like ions. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Notre Dame, Dept Phys, Notre Dame, IN 46556 USA. RP Cheng, KT (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 28 TC 21 Z9 21 U1 1 U2 2 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 NOV PY 2000 VL 62 IS 5 AR 054501 DI 10.1103/PhysRevA.62.054501 PG 4 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 371VW UT WOS:000165200800119 ER PT J AU Diamant, R Huotari, S Hamalainen, K Kao, CC Deutsch, M AF Diamant, R Huotari, S Hamalainen, K Kao, CC Deutsch, M TI CuKh alpha(1,2) hypersatellites: Suprathreshold evolution of a hollow-atom x-ray spectrum SO PHYSICAL REVIEW A LA English DT Review ID INNER-SHELL IONIZATION; ONE-PHOTON TRANSITIONS; 2-ELECTRON ONE-PHOTON; K-VACANCY PRODUCTION; DOUBLE PHOTOIONIZATION; FLUORESCENCE YIELDS; SYNCHROTRON RADIATION; BREIT INTERACTION; EMISSION SPECTRA; CROSS-SECTION AB A high-resolution pure Cu K(h)alpha (1,2) hypersatellite spectrum was measured by photoexcitation using synchrotron radiation. A shift E(K(h)alpha (2)) - E(K alpha (1)) = 281.4 +/- 0.3 eV from the diagram lines, a splitting E(K(h)alpha (1)) -E(K(h)alpha (2)) = 23.6 +/- 0.4 eV, and an intensity ratio R = I(K(h)alpha (1))/I(K(h)alpha (2)) = 0.29 +/- 0.02 are found for the two lines of the spectrum. Full-spectrum fits based on ab initio Dirac-Fock calculations agree well with the measured spectrum, when QED corrections and Breit interaction are included. A slightly higher calculated R may indicate that the intermediate coupling is not fully accounted for. The intensity's evolution from threshold (measured to be at 18.351 +/- 0.015 keV) shows an unexpectedly long saturation range extending up to similar to 30 keV. The intensity evolution deviates from the Thomas model, which should be valid in the adiabatic, near-threshold regime. The implications of our results for the Z variation of the coupling, correlations, and atomic interactions across the 3d transition elements are discussed. C1 Bar Ilan Univ, Dept Phys, IL-52900 Ramat Gan, Israel. Univ Helsinki, Dept Phys, FIN-00014 Helsinki, Finland. Brookhaven Natl Lab, NSLS, Upton, NY 11973 USA. RP Diamant, R (reprint author), Bar Ilan Univ, Dept Phys, IL-52900 Ramat Gan, Israel. RI Hamalainen, Keijo/A-3986-2010 OI Hamalainen, Keijo/0000-0002-9234-9810 NR 104 TC 45 Z9 45 U1 0 U2 2 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 NOV PY 2000 VL 62 IS 5 AR 052519 DI 10.1103/PhysRevA.62.052519 PG 14 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 371VW UT WOS:000165200800057 ER PT J AU Eisert, J Jacobs, K Papadopoulos, P Plenio, MB AF Eisert, J Jacobs, K Papadopoulos, P Plenio, MB TI Optimal local implementation of nonlocal quantum gates SO PHYSICAL REVIEW A LA English DT Article ID TRAPPED IONS; COMPUTATION; ENTANGLEMENT; STATE; FACTORIZATION; MANIPULATION; COMPUTER; CHANNELS; BOUNDS; TIME AB We investigate the minimal resources that are required in the local implementation of nonlocal quantum gates in a distributed quantum computer. Both classical communication requirements and entanglement consumption are investigated. We present general statements on the minimal resource requirements and present optimal procedures for a number of important gates, including controlled-NOT (CNOT) and Toffoli gates. We show that one bit of classical communication in each direction is both necessary and sufficient for the nonlocal implementation of the quantum CNOT, while in general two bits in each direction is required for the implementation of a general two-bit quantum gate. In particular, the state swapper requires this maximum classical communication overhead. Extensions of these ideas to multiparty gates are presented. C1 Univ Potsdam, Inst Phys, D-14469 Potsdam, Germany. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Univ London Imperial Coll Sci Technol & Med, Blackett Lab, Opt Sect, London SW7 2BW, England. RP Univ Potsdam, Inst Phys, D-14469 Potsdam, Germany. RI Jacobs, Kurt/E-7049-2011; Plenio, Martin/I-7895-2013; Eisert, Jens/D-9640-2017 OI Jacobs, Kurt/0000-0003-0828-6421; Eisert, Jens/0000-0003-3033-1292 NR 24 TC 193 Z9 204 U1 0 U2 3 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 NOV PY 2000 VL 62 IS 5 AR 052317 DI 10.1103/PhysRevA.62.052317 PG 7 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 371VW UT WOS:000165200800037 ER PT J AU Feder, DL Pindzola, MS Collins, LA Schneider, BI Clark, CW AF Feder, DL Pindzola, MS Collins, LA Schneider, BI Clark, CW TI Dark-soliton states of Bose-Einstein condensates in anisotropic traps SO PHYSICAL REVIEW A LA English DT Article ID VORTEX STABILITY; OPTICAL SOLITONS; MATTER WAVES; GAS; VORTICES; FIBERS; PULSES; APPROXIMATION; EXCITATION; CREATION AB Bark soliton states of Bose-Einstein condensates in harmonic traps are studied both analytically and computationally by the direct solution of the Gross-Pitaevskii equation in three dimensions. The ground and self-consistent excited states are found numerically by relaxation in imaginary time. The energy of a stationary soliton in a harmonic trap is shown to be independent of density and geometry for large numbers of atoms. Large-amplitude field modulation at a frequency resonant with the energy of a dark soliton is found to give rise to a state with multiple vortices. The Bogoliubov excitation spectrum of the soliton state contains complex frequencies, which disappear for sufficiently small numbers of atoms or large transverse confinement. The relationship between these complex modes and the snake instability is investigated numerically by propagation in real time. C1 Univ Oxford, Clarendon Lab, Oxford OX1 3PU, England. Natl Inst Stand & Technol, Div Electron & Opt Phys, Gaithersburg, MD 20899 USA. Auburn Univ, Dept Phys, Auburn, AL 36849 USA. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Natl Sci Fdn, Div Phys, Arlington, VA 22230 USA. RP Univ Oxford, Clarendon Lab, Parks Rd, Oxford OX1 3PU, England. RI Clark, Charles/A-8594-2009 OI Clark, Charles/0000-0001-8724-9885 NR 49 TC 159 Z9 160 U1 3 U2 9 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 NOV PY 2000 VL 62 IS 5 AR 053606 DI 10.1103/PhysRevA.62.053606 PG 11 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 371VW UT WOS:000165200800104 ER PT J AU Moxom, J Schrader, DM Laricchia, G Xu, J Hulett, LD AF Moxom, J Schrader, DM Laricchia, G Xu, J Hulett, LD TI Ionization and fragmentation of CCl2F2, CClF3, CF4, and CHF3 by positron impact SO PHYSICAL REVIEW A LA English DT Article ID ABSOLUTE OSCILLATOR-STRENGTHS; QUANTUM MONTE-CARLO; SMALL ORGANIC-MOLECULES; ELECTRON-IMPACT; FREON MOLECULES; MASS-SPECTROMETER; SINGLE IONIZATION; CROSS-SECTIONS; NOBLE-GASES; ANNIHILATION AB The fragmentation patterns of the halomethanes CCl2F2, CClF3, CF4, and CHF3 have been studied by positron impact, in the energy range from threshold to around 50 eV. These data were obtained using a quadratic potential time of flight mass spectrometer, coupled with a Penning trap and a LINAC-based positron source. The present data for positrons are compared with results for-electron and photoionization from other works. C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. Marquette Univ, Dept Chem, Milwaukee, WI 53201 USA. UCL, Dept Phys & Astron, London WC1E 6BT, England. RP Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. NR 56 TC 10 Z9 10 U1 0 U2 2 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 NOV PY 2000 VL 62 IS 5 AR 052708 DI 10.1103/PhysRevA.62.052708 PG 6 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 371VW UT WOS:000165200800065 ER PT J AU Safronova, UI Johnson, WR Albritton, JR AF Safronova, UI Johnson, WR Albritton, JR TI Relativistic many-body calculations of excitation energies and oscillator strengths in Ni-like ions SO PHYSICAL REVIEW A LA English DT Article ID NICKEL-LIKE IONS; X-RAY-SPECTRUM; NEON-LIKE IONS; ISOELECTRONIC SEQUENCE; WAVELENGTH RANGE; LINES; TRANSITION; STATES; PLASMA; RATES AB Excitation energies for 3l-4l' particle-hole states of Ni-like ions are determined to second order in relativistic many body perturbation theory. The calculations start from a closed-shell Dirac-Fock potential, and include second-order Coulomb and Breit-Coulomb interactions. Retarded electric-dipole matrix elements (in length and velocity forms) are calculated in second order for transitions from excited 3l-4l' states to the closed-shell ground state. Wavelengths for 3-4 and 4-4 transitions are compared with experimental data, and with other high-precision calculations. Trends of oscillator strengths as functions of nuclear charge Z are shown graphically for selected transitions. C1 Univ Notre Dame, Dept Phys, Notre Dame, IN 46556 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Safronova, UI (reprint author), Univ Notre Dame, Dept Phys, Notre Dame, IN 46556 USA. NR 25 TC 39 Z9 39 U1 0 U2 3 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 NOV PY 2000 VL 62 IS 5 AR 052505 DI 10.1103/PhysRevA.62.052505 PG 14 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 371VW UT WOS:000165200800043 ER PT J AU Smith, AJ Beiersdorfer, P Widmann, K Chen, MH Scofield, JH AF Smith, AJ Beiersdorfer, P Widmann, K Chen, MH Scofield, JH TI Measurement of resonant strengths for dielectronic recombination in heliumlike Ar16+ SO PHYSICAL REVIEW A LA English DT Article ID HIGHLY CHARGED IONS; CROSS-SECTIONS; RADIATIVE RECOMBINATION; SATELLITE SPECTRA; HYDROGENLIKE IONS; ARGON; BEAM; COEFFICIENTS; EXCITATION; ENERGIES AB We have measured resonant strengths for Deltan >1 dielectronic recombinaton in heliumlike Ar16+. The measurements were performed with an electron beam ion trap and include the KLM through KLP resonances contributing to n -->1 K-shell x-ray emission with n=2-6. The measured values agree within a few percent with relativistic multiconfiguration calculations. C1 Morehouse Coll, Dept Phys, Atlanta, GA 30314 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Smith, AJ (reprint author), Morehouse Coll, Dept Phys, Atlanta, GA 30314 USA. NR 26 TC 37 Z9 39 U1 0 U2 5 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 NOV PY 2000 VL 62 IS 5 AR 052717 DI 10.1103/PhysRevA.62.052717 PG 5 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 371VW UT WOS:000165200800074 ER PT J AU Ward, SJ Macek, JH AF Ward, SJ Macek, JH TI Effective range analysis of positron-hydrogen collisions SO PHYSICAL REVIEW A LA English DT Article ID CLOSE-COUPLING CALCULATION; FORMATION CROSS-SECTIONS; S-WAVE POSITRON; LOW ENERGIES; SCATTERING; THRESHOLD; CHANNEL; EXCITATION; STATE; FRAGMENTATION AB Humberston [Can. J. Phys. 60, 591 (1982)], using the Kohn variational method, showed that the range of validity of Wigner's threshold law for positronium formation in positron-hydrogen collisions is extremely narrow for the S wave. To examine the near-threshold behavior, we analyzed ab initio calculations using the multichannel effective range theory of Watanabe and Greene [Phys. Rev. A 22, 158 (1980)] and the single-channel effective range theory of Fabrikant [Opt. Spectrose 53, 131 (1982)] for the positronium-proton channel. We confirmed the presence of a Ramsauer minimum-in the L = 0 elastic cross section for positronium-proton scattering, and found a similar minimum for L = 1. The near-threshold structure is interpreted in terms of a virtual state, resonances, tunneling through and transmission over a barrier, and quantum suppression. C1 Univ N Texas, Dept Phys, Denton, TX 76203 USA. Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Ward, SJ (reprint author), Univ N Texas, Dept Phys, Denton, TX 76203 USA. NR 59 TC 7 Z9 7 U1 0 U2 4 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 NOV PY 2000 VL 62 IS 5 AR 052715 DI 10.1103/PhysRevA.62.052715 PG 15 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 371VW UT WOS:000165200800072 ER PT J AU Sun, P Schmeltzer, D Bishop, AR AF Sun, P Schmeltzer, D Bishop, AR TI Analytic approach to the one-dimensional spin-Peierls system in the entire frequency range SO PHYSICAL REVIEW B LA English DT Article ID MATRIX RENORMALIZATION-GROUP; CHARGE-DENSITY WAVES; COMPETING INTERACTIONS; PHASE-DIAGRAM; TRANSITION; MODEL; DIMERIZATION; INSULATOR; CUGEO3; (TMTTF)(2)PF6 AB We use the two cutoff renormalization group (RG) method to study the spin-Peierls model in one dimension for the entire phonon frequency range. We integrate out the phonon and solve the effective Fermion system via mean field and RG methods. We make use of the symmetry that the Neel, dimerization, and spin current order parameters form an SU(2) triplet based on resolving the fermion into left and right movers. We present the phase diagram and discuss its implications for the organic charge-transfer salt (TMTTF)(2)PF6. C1 CUNY City Coll, Dept Phys, New York, NY 10031 USA. 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 Sun, P (reprint author), CUNY City Coll, Dept Phys, Convent Ave & 138th St, New York, NY 10031 USA. NR 29 TC 8 Z9 8 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 NOV 1 PY 2000 VL 62 IS 17 BP 11308 EP 11311 DI 10.1103/PhysRevB.62.11308 PG 4 WC Physics, Condensed Matter SC Physics GA 371WH UT WOS:000165201900010 ER PT J AU Zhu, JX Ting, CS Chu, CW AF Zhu, JX Ting, CS Chu, CW TI Superconductivity in ferromagnetic RuSr2GdCu2O8 SO PHYSICAL REVIEW B LA English DT Article ID EU; GD AB The phase diagram of temperature versus exchange field is obtained within a BCS model for d-wave superconductivity in CuO2 layers which is coupled to ferromagnetic RuO2 layers in RuSr2GdCu2O8. It is found that the Fulde-Ferrell-Larkin-Ovchinnikov state is very sensitive to the band filling factor. For strong exchange field, we point out that superconductivity could only exist in the interfaces between ferromagnetic domains. The magnetization curve is calculated and its comparison with experiment is discussed. We also propose the measuring of tunneling conductance near a single unitary impurity to detect the strength of the exchange interaction. C1 Univ Houston, Texas Ctr Supercond, Houston, TX 77204 USA. Univ Houston, Dept Phys, Houston, TX 77204 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Univ Houston, Texas Ctr Supercond, Houston, TX 77204 USA. NR 23 TC 11 Z9 11 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 NOV 1 PY 2000 VL 62 IS 17 BP 11369 EP 11372 DI 10.1103/PhysRevB.62.11369 PG 4 WC Physics, Condensed Matter SC Physics GA 371WH UT WOS:000165201900026 ER PT J AU Ribeiro, FJ Cohen, ML AF Ribeiro, FJ Cohen, ML TI Theoretical prediction of the high-pressure phase Ge-Cmca SO PHYSICAL REVIEW B LA English DT Article ID STRUCTURAL-PROPERTIES; CRYSTAL STABILITY; SILICON-VI; IMMA PHASE; BETA-TIN; SI; TRANSITION; GERMANIUM; GPA; SUPERCONDUCTIVITY AB Ab initio pseudopotential total energy density-functional theory-local-density approximation calculations were performed to study the crystalline structures of Ge under pressure. Following the well established sequence of structural phases (diamond --> beta -Sn --> Imma --> sh) under increasing pressure, we predict a transition into a new phase, with Cmca space-group symmetry, at 90 +/- 2 GPa. We estimate the superconducting transition temperature T-c for this phase to be in the range 2 to 7 K, the same range obtained previously by detailed calculations for the Ge-sh phase. The Cmca phase should remain stable up to 137 +/- 10 GPa where a transition to the hcp structure is predicted to occur. The same path is followed by Si although at lower pressures. C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Lawrence Berkeley Natl Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Ribeiro, FJ (reprint author), Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. OI Ribeiro, Filipe/0000-0003-3843-7702 NR 35 TC 18 Z9 18 U1 0 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 NOV 1 PY 2000 VL 62 IS 17 BP 11388 EP 11391 DI 10.1103/PhysRevB.62.11388 PG 4 WC Physics, Condensed Matter SC Physics GA 371WH UT WOS:000165201900031 ER PT J AU Feller, JR Ketterson, JB Hinks, DG Dasgupta, D Sarma, BK AF Feller, JR Ketterson, JB Hinks, DG Dasgupta, D Sarma, BK TI Acoustic anomalies in UPt3 at high magnetic fields and low temperatures SO PHYSICAL REVIEW B LA English DT Article ID HEAVY FERMION COMPOUNDS; CERU2SI2; SURFACE AB Ultrasound velocity and attenuation measurements were performed on single crystals of the heavy fermion compound UPt3 in magnetic fields up to 33 T and at temperatures ranging from 2.4 K to below 0.1 K. With longitudinal sound propagated in the crystallographic basal plane, parallel to the applied field, the familiar elastic softening is observed at the metamagnetic transition field H similar to 20.2 T. More complicated structure emerges at low temperatures, including quantum acoustic oscillations and a second velocity minimum at similar to 21.6 T. A weak frequency dependence (dispersion) is observed in the velocity. The ultrasonic data are analyzed using the Landau-Khalatnikov formalism, from which temperature- and field-dependent relaxation times are deduced. C1 Northwestern Univ, Dept Phys & Astron, Evanston, IL 60208 USA. Argonne Natl Lab, Div Sci Mat, Argonne, IL 60439 USA. Univ Wisconsin, Dept Phys, Milwaukee, WI 53201 USA. RP Feller, JR (reprint author), Northwestern Univ, Dept Phys & Astron, Evanston, IL 60208 USA. RI Ketterson, John/B-7234-2009 NR 15 TC 9 Z9 9 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 NOV 1 PY 2000 VL 62 IS 17 BP 11538 EP 11544 DI 10.1103/PhysRevB.62.11538 PG 7 WC Physics, Condensed Matter SC Physics GA 371WH UT WOS:000165201900051 ER PT J AU Yamada, Y Suzuki, J Oikawa, K Katano, S Fernandez-Baca, JA AF Yamada, Y Suzuki, J Oikawa, K Katano, S Fernandez-Baca, JA TI Neutron diffraction of hole polaron ordering in La1-xSrxMnO3 (x similar or equal to 1/8) SO PHYSICAL REVIEW B LA English DT Article ID MANGANESE OXIDES; CHARGE; TRANSITION; MANGANITES AB The polaron-ordered structure of La1-xSrxMnO3 (x congruent to1/8) has been reinvestigated to verify the previously proposed models. We found satellite reflections on the (0,k,l)(ortho) and (1,k,l)(ortho) reciprocal planes. It has been shown that neither of the previously proposed models is completely consistent with the observed results. Based on theoretical consideration of interhole interactions in a perovskite-based structure, the experimental results are analyzed. A polaron ordered structure with unit cell size of (root 2x root 2x4)(cubic) has been proposed which is substantially consistent with the observed neutron-scattering pattern. C1 Japan Atom Energy Res Inst, Adv Sci Res Ctr, Tokai, Ibaraki 3191195, Japan. Waseda Univ, Adv Res Ctr Sci & Engn, Tokyo 1690072, Japan. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Yamada, Y (reprint author), Japan Atom Energy Res Inst, Adv Sci Res Ctr, Tokai, Ibaraki 3191195, Japan. RI Fernandez-Baca, Jaime/C-3984-2014 OI Fernandez-Baca, Jaime/0000-0001-9080-5096 NR 16 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 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD NOV 1 PY 2000 VL 62 IS 17 BP 11600 EP 11608 DI 10.1103/PhysRevB.62.11600 PG 9 WC Physics, Condensed Matter SC Physics GA 371WH UT WOS:000165201900059 ER PT J AU Hellwig, O Kortright, JB Takano, K Fullerton, EE AF Hellwig, O Kortright, JB Takano, K Fullerton, EE TI Switching behavior of Fe-Pt/Ni-Fe exchange-spring films studied by resonant soft-x-ray magneto-optical Kerr effect SO PHYSICAL REVIEW B LA English DT Article ID BILAYERS; MAGNETORESISTANCE AB We have studied the magnetic switching behavior of exchange-coupled Fe55Pt45/Ni80Fe20 films. On top of magnetically hard Fe55Pt45 films having coercive fields up to 10 kOe were deposited soft magnetic NiFe films of different thickness values to form exchange-spring magnet structures. Magnetometry measurements exhibit the loop shapes characteristic of the exchange coupling between hard and soft magnetic phases: a reversible switching of the soft layer at low fields and an irreversible switching of the hard layer at higher fields. To investigate the switching behavior in more detail we prepared samples with 20-Angstrom Co layers either deposited on top of the soft magnetic NiFe film or at the NiFe-FePt interface. Soft-x-ray magneto-optical Kerr effect measurements performed at the Co L-edge resonance allows us to use the Co layer as a local probe of the reversal process. The element specific Kerr loops reveal that the reversible twist in the soft layer is not pinned rigidly at the interface but rather propagates significantly into the hard magnetic layer. As a consequence the reversible magnetization is not only stored in the soft layer, as often assumed. Additionally the major loops do not exhibit any well-defined switching field of the hard layer. Instead the results indicate that the irreversible switching of the hard phase evolves continuously with increasing external field in this materials system. C1 IBM Corp, Almaden Res Ctr, San Jose, CA 95120 USA. Ruhr Univ Bochum, Inst Expt Phys Festkorperphys, D-44780 Bochum, Germany. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Hellwig, O (reprint author), IBM Corp, Almaden Res Ctr, 650 Harry Rd, San Jose, CA 95120 USA. RI Fullerton, Eric/H-8445-2013 OI Fullerton, Eric/0000-0002-4725-9509 NR 17 TC 57 Z9 59 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 NOV 1 PY 2000 VL 62 IS 17 BP 11694 EP 11698 DI 10.1103/PhysRevB.62.11694 PG 5 WC Physics, Condensed Matter SC Physics GA 371WH UT WOS:000165201900072 ER PT J AU Guedes, I Zaluzec, NJ Grimsditch, M Metlushko, V Vavassori, P Ilic, B Neuzil, P Kumar, R AF Guedes, I Zaluzec, NJ Grimsditch, M Metlushko, V Vavassori, P Ilic, B Neuzil, P Kumar, R TI Magnetization of negative magnetic arrays: Elliptical holes on a square lattice SO PHYSICAL REVIEW B LA English DT Article ID ANTIDOT PERMALLOY ARRAYS AB The magnetic properties of an array of elliptical holes in an Fe film have been investigated using the diffracted magneto-optical Kerr effect (D-MOKE), Lorentz scanning transmission electron microscopy (LSTEM), and Brillouin scattering. In the absence of a comprehensive theory for magnetization or magnons in these materials, we find that our results can be fit by a semiquantitative analysis treating the system as uniform, anisotropic film. D-MOKE clearly shows that magnetization reversal occurs with extensive domain formation when the held is applied along the short axis of the elliptical holes, and almost no domain formation when it is along the long axis, while LSTEM demonstrates that the domain location is controlled by the elliptical holes. A theory of D-MOKE, which enables a quantitative analysis of loops, is also presented. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Univ Illinois, Dept Elect Engn & Comp Sci, Chicago, IL 60607 USA. Univ Ferrara, I-44100 Ferrara, Italy. Cornell Univ, Sch Appl & Engn Phys, Ithaca, NY 14853 USA. Inst Microelect, Singapore 117685, Singapore. UFC, Dept Fis, BR-60455760 Fortaleza, Ceara, Brazil. RP Guedes, I (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Neuzil, Pavel/B-9981-2012; GUEDES, ILDE/C-3451-2013; Ilic, Rob/N-1359-2014; Vavassori, Paolo/B-4299-2014; UFC, DF/E-1564-2017; Universidade Federal do Ceara, Physics Department/J-4630-2016; OI Vavassori, Paolo/0000-0002-4735-6640; Universidade Federal do Ceara, Physics Department/0000-0002-9247-6780; GUEDES, ILDE/0000-0002-1040-5891 NR 12 TC 70 Z9 70 U1 0 U2 7 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD NOV 1 PY 2000 VL 62 IS 17 BP 11719 EP 11724 DI 10.1103/PhysRevB.62.11719 PG 6 WC Physics, Condensed Matter SC Physics GA 371WH UT WOS:000165201900075 ER PT J AU Johnson, DD Smirnov, AV Staunton, JB Pinski, FJ Shelton, WA AF Johnson, DD Smirnov, AV Staunton, JB Pinski, FJ Shelton, WA TI Temperature-induced configurational excitations for predicting thermodynamic and mechanical properties of alloys SO PHYSICAL REVIEW B LA English DT Article ID RANDOM SUBSTITUTIONAL ALLOYS; TRANSITION-METAL ALLOYS; SHORT-RANGE ORDER; NI-ZN SYSTEM; ELECTRONIC EXCITATIONS; PHASE-STABILITY; TRANSFORMATIONS; DISORDER AB We show that a structural energy difference, DeltaE, must include explicit symmetry-breaking changes of the electronic structure due to temperature-induced configurational excitations, and why DeltaE at T=0 K is not necessarily relevant to thermodynamic and mechanical modeling. In Ni3V, we calculate a tenfold decrease of DeltaE between D0(22) and L1(2) structures from T=0 K to states of order relevant to experiment. DeltaE calculated directly from states with short-range order (8 meV) or with low partial order (7-12 meV) agree with high-T experiment (10 meV). C1 Univ Illinois, Dept Mat Sci & Engn, Urbana, IL 61801 USA. Univ Warwick, Coventry CV4 7AL, W Midlands, England. Univ Cincinnati, Cincinnati, OH 45221 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Univ Illinois, Dept Mat Sci & Engn, 1304 W Green St, Urbana, IL 61801 USA. EM duanej@uiuc.edu NR 29 TC 24 Z9 24 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 NOV 1 PY 2000 VL 62 IS 18 BP 11917 EP 11920 PG 4 WC Physics, Condensed Matter SC Physics GA 372FW UT WOS:000165224500001 ER PT J AU Guo, CL Taylor, AJ AF Guo, CL Taylor, AJ TI Nonthermal component in heat-induced structural deformation and phase transition in gold SO PHYSICAL REVIEW B LA English DT Article ID X-RAY-DIFFRACTION; ELECTRON THERMALIZATION; DOUBLE-IONIZATION; FEMTOSECOND; DYNAMICS; COPPER; GAAS; SILICON; SI AB Using an ultrafast optical pump-probe technique, we study the dynamics of the heat-induced structural deformation and phase transition in gold at early time delays (within 1 ps after excitation) by monitoring both the fundamental and second-harmonic generation (SHG) signals of the probe beam. The ratios of the time-resolved fundamental and SHG signals with respect to low-intensity reference curves reveal clear changes immediately following pump excitation for intensities above 0.9X the melting threshold that is absent for lower intensities. These observations indicate a disordered lattice due to electronic heating and suggest that a nonthermal component exists in the heat-induced structural deformation and phase transition in gold. C1 Los Alamos Natl Lab, Div Mat Sci & Technol, Condensed Matter & Thermal Phys Grp, Los Alamos, NM 87545 USA. RP Guo, CL (reprint author), Los Alamos Natl Lab, Div Mat Sci & Technol, Condensed Matter & Thermal Phys Grp, Los Alamos, NM 87545 USA. EM cguo@lanl.gov NR 28 TC 22 Z9 23 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 NOV 1 PY 2000 VL 62 IS 18 BP 11921 EP 11924 DI 10.1103/PhysRevB.62.R11921 PG 4 WC Physics, Condensed Matter SC Physics GA 372FW UT WOS:000165224500002 ER PT J AU Wosnitza, J Wanka, S Hagel, J Haussler, R von Lohneysen, H Schlueter, JA Geiser, U Nixon, PG Winter, RW Gard, GL AF Wosnitza, J Wanka, S Hagel, J Haussler, R von Lohneysen, H Schlueter, JA Geiser, U Nixon, PG Winter, RW Gard, GL TI Shubnikov-de Haas effect in the superconducting state of an organic superconductor SO PHYSICAL REVIEW B LA English DT Article ID VAN-ALPHEN OSCILLATIONS; UPPER CRITICAL-FIELD; II SUPERCONDUCTORS; MAGNETIC-FIELDS; FERMI-SURFACE; QUANTUM OSCILLATIONS; BAND-STRUCTURE; VORTEX STATE; KAPPA-(BEDT-TTF)(2)CU(NCS)(2); DHVA AB We report the,observation of Shubnikov-de Haas (SdH) oscillations in the mixed state of the organic superconductor beta"-(BEDT-TTF)(2)SF5CH2CF2SO3 (T(c)approximate to4.4 K). At low temperatures the SdH oscillations per sist clearly below the upper critical field B-c2(0)approximate to3.6 T almost down to the field where the resistivity vanishes. Rather unusually, no additional damping of the SdH-signal amplitude - as well as of the de Haas-van Alphen amplitude - is observed in the superconducting state. This indicates that the damping in the vortex state of this quasi-two-dimensional superconductor is different in character to that observed for most three-dimensional materials. C1 Univ Karlsruhe, Inst Phys, D-76128 Karlsruhe, Germany. Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Portland State Univ, Dept Chem, Portland, OR 97207 USA. RP Wosnitza, J (reprint author), Univ Karlsruhe, Inst Phys, Kaiserstr 12, D-76128 Karlsruhe, Germany. NR 29 TC 17 Z9 17 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 NOV 1 PY 2000 VL 62 IS 18 BP 11973 EP 11976 PG 4 WC Physics, Condensed Matter SC Physics GA 372FW UT WOS:000165224500015 ER PT J AU Kortright, JB Kim, SK AF Kortright, JB Kim, SK TI Resonant magneto-optical properties of Fe near its 2p levels: Measurement and applications SO PHYSICAL REVIEW B LA English DT Article ID X-RAY-ABSORPTION; CIRCULAR-DICHROISM; EXCHANGE SCATTERING; ROUGH SURFACES; THIN-FILMS; SUM-RULES; L-EDGE; MULTILAYERS; IRON; CO AB Resonant magneto-optical properties of Fe are considered across its 2p core levels. General equivalence of the classical magneto-optical formalism (dielectric tensor) and the resonant atomic scattering factor in the electric dipole approximation is shown in describing purl charge contributions as well as first- and second-order magnetic contributions. Thickness effects in transmission absorption measurements are considered and shown to be minimized in Faraday magneto-optical rotation measurements. Transmission absorption and Faraday rotation spectra obtained using linear polarization are normalized to the complex refractive index and atomic scattering factor for pure circular modes and their polarization average, showing that the pure magnetic part is roughly 50% of the pure charge part at the L-3 resonance. Magnetic linear dichroism (Voigt effect) measured in transmission is only 2% of the pure charge scattering at resonance. These magneto-optical constants are used to calculate important polarization-dependent experimental quantities including penetration depths, critical angles for total external reflection, Kerr rotation and intensity spectra, and interference and distorted-wave effects that modulate scattering intensities. The results reveal the importance of knowledge of these properties and use of full magneto-optical formalisms in planning and interpreting experiments involving resonant 2p optical properties of the 3d transition metals. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Kortright, JB (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RI Kim, Sang-Koog/J-4638-2014 NR 58 TC 139 Z9 142 U1 6 U2 22 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 NOV 1 PY 2000 VL 62 IS 18 BP 12216 EP 12228 DI 10.1103/PhysRevB.62.12216 PG 13 WC Physics, Condensed Matter SC Physics GA 372FW UT WOS:000165224500049 ER PT J AU Sugita, H Wada, S Fisher, RA Luce, JL Stacy, AM AF Sugita, H Wada, S Fisher, RA Luce, JL Stacy, AM TI Nuclear magnetic resonance investigation of complex magnetic behavior in rare-earth cuprates: RCu2O4 (R=La and Nd) SO PHYSICAL REVIEW B LA English DT Article AB Cu-63 nuclear magnetic resonance (NMR) has been carried out to investigate the complex magnetic behavior of antiferromagnetic (AF) rare earth cuprates LaCu2O4 (T-N1 = 18 K) and NdCu2O4 (T-N1 = 23 K, T-N2= 14 K) with two inequivalent Cu sites. In the AF ordered state, two distinct zero-field Cu NMR spectra are observed in the high-frequency range (95-175 MHz) and the low-frequency range (10-32 MHz), corresponding to the magnetic Cu(I) site and the diamagnetic Cu(2) site, respectively. The ordered moment of the Cu(1) ions in LaCu2O, is estimated to be 1.09 mu (B), consistent with the expected oxidation of Cu2+ (spin=1/2). For Cu(2), the zero-held NMR in the low-frequency range is observed up to the paramagnetic state through T-N1 and the spectrum analysis indicates that the ground state is nonmagnetic, consistent with the expected Cu3+ (spin =0) state. The increase in the magnetization below TN1 is caused by canting of ordered Cu2+ moments. The second magnetic transition in NdCu2O4 has hardly any affect an the Cu-63 NMR spectra. A large decrease in the electric quadrupole frequency of Cu(2) in LaCu7O4 below T-N1 is explained as due to the contraction of the unit cell volume, which aids the magnetic ordering in LaCu2O4 that has the larger cell volume. C1 Kobe Univ, Grad Sch Sci & Technol, Dept Mat Sci, Kobe, Hyogo 6578501, Japan. Kobe Univ, Fac Sci, Dept Phys, Kobe, Hyogo 6578501, Japan. Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Sugita, H (reprint author), Kobe Univ, Grad Sch Sci & Technol, Dept Mat Sci, Kobe, Hyogo 6578501, Japan. NR 11 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 NOV 1 PY 2000 VL 62 IS 18 BP 12254 EP 12261 DI 10.1103/PhysRevB.62.12254 PG 8 WC Physics, Condensed Matter SC Physics GA 372FW UT WOS:000165224500054 ER PT J AU Pagliuso, PG Thompson, JD Hundley, MF Sarrao, JL AF Pagliuso, PG Thompson, JD Hundley, MF Sarrao, JL TI Crystal-field-induced magnetic frustration in NdMIn5 and Nd2MIn8 (M = Rh, Ir) antiferromagnets SO PHYSICAL REVIEW B LA English DT Article ID FERROMAGNETIC KONDO-LATTICE; PHASE-DIAGRAM; HIGH-PRESSURE; NDIN3; ND2CUO4; YBNISN AB We have synthesized the series of compounds NdMIn5 and Nd2MIn8 in single crystal form, where M = Rh or Lr. These materials form in tetragonal derivatives of the Cu3Au-structure NdIn3 compound. Messurements of magnetic susceptibility, electrical resistivity, and low-temperature heat capacity are reported. These compounds order antiferromagnetically at low temperature (T-N<14 K) and the evolution of their magnetic properties depends on the crystal-field ground-state configuration. Comparison between the present data and magnetic properties of the isostructural new heavy fermion compounds Ce(Rh,Ir)In-5 and Ce-2(Rh,Ir)In-8 suggests that crystal field effects and magnetic anisotropy should be taken into account to understand the rich phase diagram of these compounds. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Pagliuso, PG (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. RI Pagliuso, Pascoal/C-9169-2012 NR 21 TC 35 Z9 35 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 NOV 1 PY 2000 VL 62 IS 18 BP 12266 EP 12270 DI 10.1103/PhysRevB.62.12266 PG 5 WC Physics, Condensed Matter SC Physics GA 372FW UT WOS:000165224500056 ER PT J AU Nordborg, H Vinokur, VM AF Nordborg, H Vinokur, VM TI Interaction between a vortex and a columnar defect in the London approximation SO PHYSICAL REVIEW B LA English DT Article ID VORTICES AB We calculate the interaction between a vortex and an insulating cylindrical cavity in a type-II superconductor using the London approximation, thus extending the result in an earlier work by Mkrtchyan and Shmidt (Zh. Eksp. Teor. Fit 61, 367 (1971) [Sov. Phys. JETP 34, 195 (1972)]) to an arbitrarily large cavity radius. In the limit of an infinitely large radius our result reduces to the well-known Bean-Livingston formula far the interaction between a vortex and an insulating wall. C1 Argonne Natl Lab, Div Sci Mat, Argonne, IL 60469 USA. RP Argonne Natl Lab, Div Sci Mat, Argonne, IL 60469 USA. OI Nordborg, Henrik/0000-0003-3432-3257 NR 12 TC 37 Z9 38 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 NOV 1 PY 2000 VL 62 IS 18 BP 12408 EP 12412 DI 10.1103/PhysRevB.62.12408 PG 5 WC Physics, Condensed Matter SC Physics GA 372FW UT WOS:000165224500072 ER PT J AU Kim, D Berghuis, P Field, MB Miller, DJ Gray, KE Feenstra, R Christen, DK AF Kim, D Berghuis, P Field, MB Miller, DJ Gray, KE Feenstra, R Christen, DK TI Evidence for pinning of grain-boundary vortices by Abrikosov vortices in the grains of YBa2CU3O7 SO PHYSICAL REVIEW B LA English DT Article ID SUPERCONDUCTING TAPES; CRITICAL CURRENTS; FLUX; FILMS; FIELD AB Data as a function of magnetic field on two types of bicrystal grain boudaries (GB's) of high-T-c superconductors show a peak in the critical current and an unusual inverse hysteresis. These results support a mechanism for an enhanced GB critical current, arising from interactions of GB vortices with pinned Abrikosov vortices in the banks of a GB, as suggested by Gurevich and Cooley. A substantial fraction of this enhancement (of order a factor of 2 after field cooling) also occurs upon exceeding the critical current of the grains after zero field cooling. A bulk GB and an isolated GB from a coated conductor show qualitatively identical results. C1 Argonne Natl Lab, Div Sci Mat, Argonne, IL 60439 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Yeungnam Univ, Dept Phys, Kyongsan 712749, South Korea. RP Kim, D (reprint author), Argonne Natl Lab, Div Sci Mat, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 12 TC 13 Z9 13 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 NOV 1 PY 2000 VL 62 IS 18 BP 12505 EP 12508 DI 10.1103/PhysRevB.62.12505 PG 4 WC Physics, Condensed Matter SC Physics GA 372FW UT WOS:000165224500083 ER PT J AU Andreoiu, C Rudolph, D Svensson, CE Afanasjev, AV Dobaczewski, J Ragnarsson, I Baktash, C Eberth, J Fahlander, C Haslip, DS LaFosse, DR Paul, SD Sarantites, DG Thomas, HG Waddington, JC Weintraub, W Wilson, JN Yu, CH AF Andreoiu, C Rudolph, D Svensson, CE Afanasjev, AV Dobaczewski, J Ragnarsson, I Baktash, C Eberth, J Fahlander, C Haslip, DS LaFosse, DR Paul, SD Sarantites, DG Thomas, HG Waddington, JC Weintraub, W Wilson, JN Yu, CH TI Yrast superdeformed band in Cu-59 SO PHYSICAL REVIEW C LA English DT Article ID A-SIMILAR-TO-60 MASS REGION; ROTATIONAL BANDS; N=Z; PARAMETRIZATION; NI-56; DECAY; ZN-60 AB High-spin states in Cu-59 were populated using the fusion-evaporation reactions Si-28+ Ca-40 at a beam energy of 125 MeV and Ar-36+Si-28 at a beam energy of 143 MeV. The Gammasphere array in conjunction with ancillary detector systems allowed for the identification of a superdeformed rotational band in Cu-59, which was firmly linked to low-spin yrast states. Using directional correlations of oriented states, a spin-parity assignment of I-pi=25/2(+) to the band head was possible. The average quadrupole moment of the band is measured to be Q(t)=(2.24+/-0.40) e b. The characteristics of the band are compared to neighboring nuclei and predictions of different mean-field theories. C1 Univ Lund, Dept Phys, S-22100 Lund, Sweden. NIPNE Horia Hulubei, RO-76900 Bucharest, Romania. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. Tech Univ Munich, Dept Phys, D-85747 Garching, Germany. Univ Latvia, Inst Solid State Phys, Lab Radiat Phys, LV-2169 Salaspils, Latvia. Univ Warsaw, Inst Theoret Phys, PL-00681 Warsaw, Poland. Lund Inst Technol, Dept Math Phys, S-22100 Lund, Sweden. Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. Univ Cologne, Inst Kernphys, D-50937 Cologne, Germany. McMaster Univ, Dept Phys & Astron, Hamilton, ON L8S 4M1, Canada. Washington Univ, Dept Chem, St Louis, MO 63130 USA. Univ Tennessee, Dept Phys, Knoxville, TN 37996 USA. RP Andreoiu, C (reprint author), Univ Lund, Dept Phys, S-22100 Lund, Sweden. RI Rudolph, Dirk/D-4259-2009 OI Rudolph, Dirk/0000-0003-1199-3055 NR 22 TC 27 Z9 27 U1 1 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 NOV PY 2000 VL 62 IS 5 AR 051301 DI 10.1103/PhysRevC.62.051301 PG 5 WC Physics, Nuclear SC Physics GA 374XF UT WOS:000165369400001 ER PT J AU Bardayan, DW Blackmon, JC Brune, CR Champagne, AE Chen, AA Cox, JM Davinson, T Hansper, VY Hofstee, MA Johnson, BA Kozub, RL Ma, Z Parker, PD Pierce, DE Rabban, MT Shotter, AC Smith, MS Swartz, KB Visser, DW Woods, PJ AF Bardayan, DW Blackmon, JC Brune, CR Champagne, AE Chen, AA Cox, JM Davinson, T Hansper, VY Hofstee, MA Johnson, BA Kozub, RL Ma, Z Parker, PD Pierce, DE Rabban, MT Shotter, AC Smith, MS Swartz, KB Visser, DW Woods, PJ TI The astrophysically important 3(+) state in Ne-18 and the F-17(p,gamma)Ne-18 stellar rate SO PHYSICAL REVIEW C LA English DT Article ID HOT CNO CYCLE; HIGH-RESOLUTION; NOVA OUTBURSTS; NUCLEOSYNTHESIS; SCATTERING; EVOLUTION; BEAMS; MASS AB Knowledge of the F-17(p, gamma)Ne-18 reaction rate is important for understanding stellar explosions, but it was uncertain because the properties of an expected but previously unobserved 3(+) state in Ne-18 were not known. This state would provide a strong s-wave resonance for the F-17+p system and, depending on its excitation energy, could dominate the stellar reaction rate at temperatures above 0.2 GK. We have observed this missing 3(+) state by measuring the H-1(F-17,p)F-17 excitation function with a radioactive F-17 beam at the ORNL Holifield Radioactive Ion Beam Facility (HRIBF). We find that the state lies at a center-of-mass energy of E-r=599.8. +/-1.5(stat)+/-2.0(sys) keV (E-x=4523.7+/-2.9 keV) and has a width of Gamma =18+/-2(stat)+/-1(sys) keV. The measured properties of the resonance are only consistent with a J(pi)=3(+) assignment. C1 Univ N Carolina, Dept Phys & Astron, Chapel Hill, NC 27599 USA. Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. Yale Univ, AW Wright Nucl Struct Lab, New Haven, CT 06520 USA. Tennessee Technol Univ, Dept Phys, Cookeville, TN 38505 USA. Univ Edinburgh, Dept Phys & Astron, Edinburgh EH9 3JZ, Midlothian, Scotland. Colorado Sch Mines, Dept Phys, Golden, CO 80401 USA. Chinese Inst Atom Energy, Beijing 102413, Peoples R China. Joint Inst Heavy Ion Res, Oak Ridge, TN 37831 USA. RP Bardayan, DW (reprint author), Univ N Carolina, Dept Phys & Astron, Chapel Hill, NC 27599 USA. RI Visser, Dale/A-8117-2009 OI Visser, Dale/0000-0002-2891-4731 NR 52 TC 63 Z9 63 U1 0 U2 3 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 NOV PY 2000 VL 62 IS 5 AR 055804 DI 10.1103/PhysRevC.62.055804 PG 14 WC Physics, Nuclear SC Physics GA 374XF UT WOS:000165369400067 ER PT J AU Barmore, B Kruppa, AT Nazarewicz, W Vertse, T AF Barmore, B Kruppa, AT Nazarewicz, W Vertse, T TI Theoretical description of deformed proton emitters: Nonadiabatic coupled-channel method SO PHYSICAL REVIEW C LA English DT Article ID DRIP-LINE; NUCLEI; DECAY; SPECTROSCOPY; STATES; IDENTIFICATION; RADIOACTIVITY; ENERGIES; SN-100; BANDS AB The newly developed nonadiabatic method based on the coupled-channel Schrodinger equation with Gamow states is used to study the phenomenon of proton radioactivity. The new method, adopting the weak coupling regime of the particle-plus-rotor model, allows for the inclusion of excitations in the daughter nucleus. This can lead to rather different predictions for lifetimes and branching ratios as compared to the standard adiabatic approximation corresponding to the strong coupling scheme. Calculations are performed for several experimentally seen, nonspherical nuclei beyond the proton dripline. By comparing theory and experiment, we are able to characterize the angular momentum content of the observed narrow resonance. C1 Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Joint Inst Heavy Ion Res, Oak Ridge, TN 37831 USA. Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. Hungarian Acad Sci, Inst Nucl Res, H-4001 Debrecen, Hungary. Univ Warsaw, Inst Theoret Phys, PL-00681 Warsaw, Poland. RP Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. NR 54 TC 86 Z9 88 U1 1 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9985 EI 2469-9993 J9 PHYS REV C JI Phys. Rev. C PD NOV PY 2000 VL 62 IS 5 AR 054315 DI 10.1103/PhysRevC.62.054315 PG 12 WC Physics, Nuclear SC Physics GA 374XF UT WOS:000165369400031 ER PT J AU Bentley, MA Williams, SJ Joss, DT O'Leary, CD Bruce, AM Cameron, JA Carpenter, MP Fallon, P Frankland, L Gelletly, W Lister, CJ Martinez-Pinedo, G Poves, A Regan, PH Reiter, P Rubio, B Solano, JS Seweryniak, D Svensson, CE Vincent, SM Warner, DD AF Bentley, MA Williams, SJ Joss, DT O'Leary, CD Bruce, AM Cameron, JA Carpenter, MP Fallon, P Frankland, L Gelletly, W Lister, CJ Martinez-Pinedo, G Poves, A Regan, PH Reiter, P Rubio, B Solano, JS Seweryniak, D Svensson, CE Vincent, SM Warner, DD TI Mirror symmetry at high spin in Fe-51 and Mn-51 SO PHYSICAL REVIEW C LA English DT Article ID FULL PF SHELL; NUCLEI; STATES; CR-48; MN-49; MODEL AB Gamma decays from excited states in the T-z= -1/2 nucleus Fe-51 have been observed for the first time. The differences in excitation energies as compared with those of the mirror partner, Mn-51, have been interpreted in terms of Coulomb effects and the resulting Coulomb energy differences (CED) can be understood intuitively in terms of particle-alignment effects. A new CED effect has been observed, in which different CED trends have been measured for each signature of the rotational structures that characterize these mind-f(7/2) shell nuclei. Large-scale fp-shell model calculations have been used to compute the trends of the CED as a function of spin. The result of comparing these calculations with the data demonstrates an ability to reproduce the fine details of the Coulomb effects with a precision far greater than has been previously achieved. C1 Staffordshire Univ, Sch Sci, Stoke On Trent ST4 2DE, Staffs, England. Univ Liverpool, Oliver Lodge Lab, Liverpool L69 7ZE, Merseyside, England. Univ Brighton, Sch Engn, Brighton BN2 4GJ, E Sussex, England. McMaster Univ, Hamilton, ON L8S 4K1, Canada. Argonne Natl Lab, Argonne, IL 60439 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Surrey, Sch Phys & Chem, Guildford GU2 7XH, Surrey, England. Aarhus Univ, Dept Phys & Astron, DK-8000 Aarhus, Denmark. Univ Autonoma Madrid, Dept Fis Teor C 11, E-28049 Madrid, Spain. Univ Valencia, CSIC, E-46071 Valencia, Spain. CLRC, Daresbury Lab, Warrington WA4 4AD, Cheshire, England. RP Staffordshire Univ, Sch Sci, Stoke On Trent ST4 2DE, Staffs, England. RI Poves, Alfredo/L-2594-2013; Carpenter, Michael/E-4287-2015; Martinez-Pinedo, Gabriel/A-1915-2013; Rubio, Berta/M-1060-2014 OI Poves, Alfredo/0000-0001-7539-388X; Carpenter, Michael/0000-0002-3237-5734; Martinez-Pinedo, Gabriel/0000-0002-3825-0131; Rubio, Berta/0000-0002-9149-4151 NR 20 TC 51 Z9 51 U1 0 U2 0 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 NOV PY 2000 VL 62 IS 5 AR 051303 DI 10.1103/PhysRevC.62.051303 PG 5 WC Physics, Nuclear SC Physics GA 374XF UT WOS:000165369400003 ER PT J AU Garrett, PE Bernstein, LA Becker, JA Hauschild, K McGrath, CA McNabb, DP Younes, W Chadwick, MB Johns, GD Nelson, RO Wilburn, WS Tavukcu, E Yates, SW AF Garrett, PE Bernstein, LA Becker, JA Hauschild, K McGrath, CA McNabb, DP Younes, W Chadwick, MB Johns, GD Nelson, RO Wilburn, WS Tavukcu, E Yates, SW TI Mo-92(n,xn yp z alpha gamma) reactions for neutron energies up to 250 MeV SO PHYSICAL REVIEW C LA English DT Article AB Excitation functions from the interaction of fast neutrons (up to an energy of 250 MeV) on a target of Mo-92 have been measured. Yields have been determined for reaction gamma rays from Mo88-92, Nb88-92, Zr86-91, Y-84-86,Y-88, and Sr80.82-86. These results are compared with model calculations using the GNASH code which takes into account compound nucleus, preequilibrium emission,multiple preequilibrium emission, and direct reaction contributions. The model calculations are in good agreement overall, but significant discrepancies emerge for some high-multiplicity, charged-particle-exit channels. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. N Carolina State Univ, Raleigh, NC 27695 USA. Univ Kentucky, Lexington, KY 40506 USA. RP Garrett, PE (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RI Hauschild, Karl/A-6726-2009; McGrath, Christopher/E-8995-2013 NR 21 TC 13 Z9 13 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 NOV PY 2000 VL 62 IS 5 AR 054608 DI 10.1103/PhysRevC.62.054608 PG 13 WC Physics, Nuclear SC Physics GA 374XF UT WOS:000165369400044 ER PT J AU Kadmensky, SG Sonzogni, AA AF Kadmensky, SG Sonzogni, AA TI Proton angular distributions from oriented proton-emitting nuclei SO PHYSICAL REVIEW C LA English DT Article ID DEFORMED-NUCLEI; ALPHA-DECAY; ISOTOPES; STATE; RADIOACTIVITY; SPECTROSCOPY; ANISOTROPY; EMITTERS; EMISSION AB Angular distributions of protons emitted from ground and isomeric states in oriented nuclei are calculated. Odd-Z, odd-A proton emitting nuclei are considered in this work. The shape of the angular distributions shows strong dependence with the angular momentum carried away by the proton. They can be used potentially as a spectroscopic tool. C1 Voronezh State Univ, Dept Nucl Phys, RU-394000 Voronezh, Russia. Argonne Natl Lab, Argonne, IL 60439 USA. RP Kadmensky, SG (reprint author), Brookhaven Natl Lab, NNDC, Bldg 197D, Upton, NY 11973 USA. EM kadmensky@cd.vsu.ru; sonzogni@bnl.gov NR 32 TC 16 Z9 16 U1 1 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 NOV PY 2000 VL 62 IS 5 AR 054601 DI 10.1103/PhysRevC.62.054601 PG 5 WC Physics, Nuclear SC Physics GA 374XF UT WOS:000165369400037 ER PT J AU Koehler, PE Winters, RR Guber, KH Rauscher, T Harvey, JA Raman, S Spencer, RR Blackmon, JC Larson, DC Bardayan, DW Lewis, TA AF Koehler, PE Winters, RR Guber, KH Rauscher, T Harvey, JA Raman, S Spencer, RR Blackmon, JC Larson, DC Bardayan, DW Lewis, TA TI High-resolution neutron capture and transmission measurements, and the stellar neutron-capture cross section of Sr-88 SO PHYSICAL REVIEW C LA English DT Article ID S-PROCESS NUCLEOSYNTHESIS; RESONANCE SPECTROSCOPY; DENSITY; LEVEL; MODEL AB We have made new and improved measurements of the neutron capture and total cross sections for Sr-88 at the Oak Ridge Electron Linear Accelerator (ORELA). Improvements over previous measurements include a wider incident neutron energy range, better resolution, the use of metallic rather than carbonate samples, better background subtraction, reduced sensitivity to sample-dependent backgrounds, and better pulse-height weighting functions. Because of its small cross section, the Sr-88(n,gamma) reaction is an important bottleneck during s-process nucleosynthesis. Hence, an accurate determination of this rate is needed to better constrain the neutron exposure in s-process models and to better understand the recently discovered isotopic anomalies in certain meteorites. We performed an R-matrix analysis of our capture and transmission data to extract parameters for 101 resonances between 100 eV and 350 keV. In addition, we fitted our transmission data alone to extract parameters for 342 additional resonances between 350 and 950 keV. We used this information to calculate average properties of the Sr-88+ n system for comparison to previous work. Although previous data and resonance analyses were much less extensive, they are, in general, in good agreement with our results except that the average radiation widths as well as the p-wave correlation coefficients we determined are significantly smaller, and the s-wave correlation coefficient we determined has opposite sign from that reported in previous work. We used these resonance parameters together with a calculation of the small, but significant direct-capture contribution to determine the astrophysical reaction rate for the Sr-88(n,gamma) reaction to approximately 3% accuracy across the entire range of temperatures needed by s-process models. Our new rate is in good agreement with the results from a high-precision activation measurement at kT=25 keV, but it is approximately 9.5% lower than the rate used in most previous nucleosynthesis calculations in the temperature range (kT=6-8 keV), where most of the neutron exposure occurs in current stellar models of the s process. We discuss the possible astrophysical impact of this new, lower rate. C1 Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. Denison Univ, Dept Phys, Granville, OH 43023 USA. Oak Ridge Natl Lab, Computat Phys & Engn Div, Oak Ridge, TN 37831 USA. Univ Basel, Dept Phys & Astron, CH-4056 Basel, Switzerland. Univ Calif Santa Cruz, Dept Astron & Astrophys, Santa Cruz, CA 95064 USA. RP Koehler, PE (reprint author), Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. RI Rauscher, Thomas/D-2086-2009; OI Rauscher, Thomas/0000-0002-1266-0642; Koehler, Paul/0000-0002-6717-0771 NR 36 TC 35 Z9 35 U1 0 U2 3 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 NOV PY 2000 VL 62 IS 5 AR 055803 DI 10.1103/PhysRevC.62.055803 PG 15 WC Physics, Nuclear SC Physics GA 374XF UT WOS:000165369400066 ER PT J AU Lising, LJ Hwang, SR Adams, JM Bowles, TJ Browne, MC Chupp, TE Coulter, KP Dewey, MS Freedman, SJ Fujikawa, BK Garcia, A Greene, GL Jones, GL Mumm, HP Nico, JS Richardson, JM Robertson, RGH Steiger, TD Teasdale, WA Thompson, AK Wasserman, EG Wietfeldt, FE Welsh, RC Wilkerson, JF AF Lising, LJ Hwang, SR Adams, JM Bowles, TJ Browne, MC Chupp, TE Coulter, KP Dewey, MS Freedman, SJ Fujikawa, BK Garcia, A Greene, GL Jones, GL Mumm, HP Nico, JS Richardson, JM Robertson, RGH Steiger, TD Teasdale, WA Thompson, AK Wasserman, EG Wietfeldt, FE Welsh, RC Wilkerson, JF CA emiT Collaboration TI New limit on the D coefficient in polarized neutron decay SO PHYSICAL REVIEW C LA English DT Article ID TIME-REVERSAL INVARIANCE; ELECTRIC-DIPOLE MOMENT; CP-VIOLATION; BETA-DECAY; SUPERMIRRORS; KAON AB We describe an experiment that has set new limits on the time reversal invariance violating D coefficient in neutron beta decay. The emiT experiment measured the angular correlation [J] . (p(e) x p(p)) using an octagonal symmetry that optimizes electron-proton coincidence rates. The result is D=[-0.6+/-1.2(stat)+/-0.5(syst)] x 10(-3). This improves constraints on the phase of g(A)/g(V) and limits contributions to T violation due to leptoquarks. This paper presents details of the experiment, data analysis, and the investigation of systematic effects. C1 Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Univ Calif Berkeley, Berkeley, CA 94720 USA. Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Michigan, Ann Arbor, MI 48101 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Notre Dame, Notre Dame, IN 46556 USA. Harvard Univ, Cambridge, MA 02138 USA. Univ Washington, Seattle, WA 98195 USA. RP Lising, LJ (reprint author), Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. NR 28 TC 53 Z9 53 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 NOV PY 2000 VL 62 IS 5 AR 055501 DI 10.1103/PhysRevC.62.055501 PG 11 WC Physics, Nuclear SC Physics GA 374XF UT WOS:000165369400062 ER PT J AU Mahmud, H Davids, CN Woods, PJ Davinson, T Henderson, DJ Irvine, RJ Seweryniak, D Walters, WB AF Mahmud, H Davids, CN Woods, PJ Davinson, T Henderson, DJ Irvine, RJ Seweryniak, D Walters, WB TI alpha radioactivity of Os-162 and W-158 SO PHYSICAL REVIEW C LA English DT Article AB alpha decay measurements for Os-162, W-158, and W-158m are presented. Os-162 was produced via fusion evaporation of a 270 MeV Ni-58 beam on a Cd-106 target and then implanted in a doubled-sided silicon strip detector (DSSD). The Os-162-W-158 alpha -decay mother-daughter correlation was then studied. W-158m was directly populated in a similar experiment with a Pd-102 target. Using the measurements obtained for Os-162 [E-alpha = 6600(3) keV, t(1/2) = 1.9(2) ms], W-158 [E-alpha = 6445(3) keV, t(1/2) = 1.5(2) ms, b(alpha) = 96(6)%], and W-158m [E-alpha = 8286(7) keV, t(1/2) = 0.14(2) ms], alpha -reduced widths were calculated. C1 Univ Edinburgh, Dept Phys & Astron, Edinburgh EH9 3JZ, Midlothian, Scotland. Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. Univ Maryland, Dept Chem, College Pk, MD 20742 USA. RP Mahmud, H (reprint author), Univ Edinburgh, Dept Phys & Astron, Edinburgh EH9 3JZ, Midlothian, Scotland. NR 13 TC 16 Z9 16 U1 0 U2 6 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 NOV PY 2000 VL 62 IS 5 AR 057303 DI 10.1103/PhysRevC.62.057303 PG 3 WC Physics, Nuclear SC Physics GA 374XF UT WOS:000165369400071 ER PT J AU Malov, S Wijesooriya, K Baker, FT Bimbot, L Brash, EJ Chang, CC Finn, JM Fissum, KG Gao, J Gilman, R Glashausser, C Jones, MK Kelly, JJ Kumbartzi, G Liyanage, N McIntyre, J Nanda, S Perdrisat, CF Punjabi, VA Quemener, G Ransome, RD Rutt, PM Zainea, DG Anderson, BD Aniol, KA Auerbach, L Berthot, J Bertozzi, W Bertin, PY Boeglin, WU Breton, V Breuer, H Burtin, E Calarco, JR Cardman, L Cates, GD Cavata, C 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 Fleniken, J Fonvieille, H Frois, B Frullani, S Garibaldi, F Gasparian, A Gilad, S Glamazdin, A Gomez, J Gorbenko, V Gorringe, T Griffioen, K Hersman, FW Hines, J Holmes, R Holtrop, M d'Hose, N Howell, C Huber, GM Hyde-Wright, CE Iodice, M de Jager, CW Jaminion, S Joo, K Jutier, C Kahl, W Kato, S Kerhoas, S Khandaker, M Khayat, M Kino, K Korsch, W Kramer, L Kumar, KS Laveissiere, G Leone, A LeRose, JJ Levchuk, L Liang, M Lindgren, RA Lolos, GJ Lourie, RW Madey, R Maeda, K Manley, DM Margaziotis, DJ Markowitz, P Marroncle, J Martino, J McCarthy, JS McCormick, K van der Meer, RLJ Meziani, ZE Michaels, R Mougey, J Neyret, D Offermann, EAJM Papandreou, Z Perrino, R Petratos, GG Platchkov, S Pomatsalyuk, R Prout, DL Pussieux, T Ravel, O Roblin, Y Roche, R Rowntree, D Rutledge, GA 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 Wilson, R Wojtsekhowski, B Zeps, V Zhao, J Zhou, ZL AF Malov, S Wijesooriya, K Baker, FT Bimbot, L Brash, EJ Chang, CC Finn, JM Fissum, KG Gao, J Gilman, R Glashausser, C Jones, MK Kelly, JJ Kumbartzi, G Liyanage, N McIntyre, J Nanda, S Perdrisat, CF Punjabi, VA Quemener, G Ransome, RD Rutt, PM Zainea, DG Anderson, BD Aniol, KA Auerbach, L Berthot, J Bertozzi, W Bertin, PY Boeglin, WU Breton, V Breuer, H Burtin, E Calarco, JR Cardman, L Cates, GD Cavata, C 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 Fleniken, J Fonvieille, H Frois, B Frullani, S Garibaldi, F Gasparian, A Gilad, S Glamazdin, A Gomez, J Gorbenko, V Gorringe, T Griffioen, K Hersman, FW Hines, J Holmes, R Holtrop, M d'Hose, N Howell, C Huber, GM Hyde-Wright, CE Iodice, M de Jager, CW Jaminion, S Joo, K Jutier, C Kahl, W Kato, S Kerhoas, S Khandaker, M Khayat, M Kino, K Korsch, W Kramer, L Kumar, KS Laveissiere, G Leone, A LeRose, JJ Levchuk, L Liang, M Lindgren, RA Lolos, GJ Lourie, RW Madey, R Maeda, K Manley, DM Margaziotis, DJ Markowitz, P Marroncle, J Martino, J McCarthy, JS McCormick, K van der Meer, RLJ Meziani, ZE Michaels, R Mougey, J Neyret, D Offermann, EAJM Papandreou, Z Perrino, R Petratos, GG Platchkov, S Pomatsalyuk, R Prout, DL Pussieux, T Ravel, O Roblin, Y Roche, R Rowntree, D Rutledge, GA 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 Wilson, R Wojtsekhowski, B Zeps, V Zhao, J Zhou, ZL CA Jefferson Lab Hall A Collaboration TI Polarization transfer in the O-16((e)over-right-arrow,e '(p)over-right-arrow)N-15 reaction SO PHYSICAL REVIEW C LA English DT Article ID ELECTROMAGNETIC FORM-FACTORS; ELASTIC ELECTRON-SCATTERING; NUCLEAR-MEDIUM; RESPONSE FUNCTIONS; COULOMB SUM; PROTON; DEPENDENCE; MESON; KNOCKOUT; MODEL AB The first ((e) over right arrow ,e'(p) over right arrow) polarization transfer measurements on a nucleus heavier than deuterium have been carried out at Jefferson Laboratory. Transverse and longitudinal components of the polarization of protons ejected in the reaction O-16((e) over right arrow ,e'(p) over right arrow) were measured in quasielastic perpendicular kinematics at a Q(2) of 0.8 (GeV/c)(2). The data are in good agreement with state of the art calculations. C1 Rutgers State Univ, Piscataway, NJ 08854 USA. Univ Blaise Pascal, IN2P3, F-63177 Clermont Ferrand, France. Calif State Univ Los Angeles, Los Angeles, CA 90032 USA. Univ Grenoble 1, Inst Sci Nucl, F-38026 St Martin Dheres, 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, Sez Bari, I-70126 Bari, Italy. Univ Bari, I-70126 Bari, Italy. Ist Nazl Fis Nucl, Sez 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. MIT, Cambridge, MA 02139 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 Malov, S (reprint author), Rutgers State Univ, Piscataway, NJ 08854 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 OI Perrino, Roberto/0000-0002-5764-7337; McIntyre, Justin/0000-0002-3706-4310; NR 45 TC 42 Z9 42 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 NOV PY 2000 VL 62 IS 5 AR 057302 DI 10.1103/PhysRevC.62.057302 PG 5 WC Physics, Nuclear SC Physics GA 374XF UT WOS:000165369400070 ER PT J AU Navratil, P Vary, JP Barrett, BR AF Navratil, P Vary, JP Barrett, BR TI Large-basis ab initio no-core shell model and its application to C-12 SO PHYSICAL REVIEW C LA English DT Article ID VIOLATING ELECTRON-SCATTERING; MONTE-CARLO CALCULATIONS; LIGHT-NUCLEI; GROUND-STATE; OPERATOR APPROACH; BINDING-ENERGIES; CROSS-SECTIONS; STRENGTH; 3-BODY; O-16 AB We present the framework for the ab initio no-core nuclear shell model and apply it to obtain properties of C-12. We derive two-body effective interactions microscopically for specific model spaces from the realistic CD-Bonn and the Argonne V8' nucleon-nucleon (NN) potentials. We then evaluate binding energies, excitation spectra, radii, and electromagnetic transitions in the 0 (h) over bar Ohm, 2 (h) over bar Ohm, and 4 (h) over bar Ohm model spaces for the positive-parity states and the 1 (h) over bar Ohm, 3 (h) over bar Ohm, and 5 (h) over bar Ohm model spaces for the negative-parity states. Dependence on the model-space size, on the harmonic-oscillator frequency, and on the type of the NN potential, used for the effective interaction derivation, are studied. In addition, electromagnetic and weak neutral elastic charge form factors are calculated in the impulse approximation. Sensitivity of the form-factor ratios to the strangeness one-body form-factor parameters and to the influence of isospin-symmetry violation is evaluated and discussed. Agreement between theory and experiment is favorable for many observables, while others require yet larger model spaces and/or three-body forces. The limitations of the present results are easily understood by virtue of the trends established and previous phenomenological results. C1 Univ Arizona, Dept Phys, Tucson, AZ 85721 USA. Acad Sci Czech Republic, Inst Nucl Phys, CZ-25068 Rez, Czech Republic. Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. Iowa State Univ, Int Inst Theoret & Appl Phys, Ames, IA 50011 USA. RP Lawrence Livermore Natl Lab, POB 808, Livermore, CA 94551 USA. NR 56 TC 336 Z9 339 U1 0 U2 9 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 NOV PY 2000 VL 62 IS 5 AR 054311 DI 10.1103/PhysRevC.62.054311 PG 14 WC Physics, Nuclear SC Physics GA 374XF UT WOS:000165369400027 ER PT J AU Piechaczek, A Zganjar, EF Batchelder, JC MacDonald, BD Kulp, WD Paul, SD Terry, R Wood, JL AF Piechaczek, A Zganjar, EF Batchelder, JC MacDonald, BD Kulp, WD Paul, SD Terry, R Wood, JL TI beta decay of the T=0 isomer in the N = Z proton drip-line nucleus Br-70 SO PHYSICAL REVIEW C LA English DT Article ID N=Z; IDENTIFICATION; FRAGMENTATION; TRANSITIONS; COEXISTENCE; ISOTOPES; STATES; SE-72; BANDS; SPIN AB We have investigated the beta decay of the T = 0, T(1/2)approximate to2.2 s, isomeric level in the self-conjugate odd-odd nucleus Br-70. The observed beta -delayed gamma rays in the daughter nucleus Se-70 and the deduced decay properties of the isomeric level allow, in conjunction with results from the deformed shell model, a spin and parity assignment of J(pi) = 9(+) and suggest a structure of {pi [404]9/2(+) nu [404]9/2(+)}9(+). The allowed unhindered beta decay of the isomer, possibly oblate deformed, proceeds to four-quasiparticle states in Se-70. C1 Louisiana State Univ, Dept Phys & Astron, Baton Rouge, LA 70803 USA. Oak Ridge Associated Univ, UNIRIB, Oak Ridge, TN 37831 USA. Georgia Inst Technol, Sch Phys, Atlanta, GA 30332 USA. Oak Ridge Inst Sci & Educ, Oak Ridge, TN 37831 USA. Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. RP Piechaczek, A (reprint author), Louisiana State Univ, Dept Phys & Astron, Baton Rouge, LA 70803 USA. NR 28 TC 15 Z9 16 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 NOV PY 2000 VL 62 IS 5 AR 054317 DI 10.1103/PhysRevC.62.054317 PG 5 WC Physics, Nuclear SC Physics GA 374XF UT WOS:000165369400033 ER PT J AU Ping, JL Wang, F Goldman, T AF Ping, JL Wang, F Goldman, T TI d ' dibaryon in the quark-delocalization, color-screening model SO PHYSICAL REVIEW C LA English DT Article ID INTERMEDIATE RANGE ATTRACTION; PI-NN RESONANCE; DOUBLE-CHARGE-EXCHANGE; FRACTIONAL-PARENTAGE; LOW ENERGIES; CLUSTER MODEL; SIGNATURE; DYNAMICS; BARYONS; SEARCH AB We study the questions of the existence and mass of the proposed d'(IJ(P) = OO-) dibaryon in the quark-delocalization, color-screening model. The transformation between physical and symmetry bases has been extended to the cases beyond the SU(2) orbital symmetry. Using parameters fixed by baryon properties and NN scattering, we find a mild attraction in the IJ(P) = OO- channel, but it is not strong enough to form a deeply bound state as proposed for the d' state. Nor does the (isospin) 1=2 N Delta configuration have a deeply bound state. These results show that if a narrow dibaryon d' state does exist, it must have a more complicated structure. C1 Nanjing Univ, Dept Phys, Nanjing 210093, Peoples R China. Nanjing Normal Univ, Dept Phys, Nanjing 210097, Peoples R China. Nanjing Univ, Ctr Theoret Phys, Nanjing 210093, Peoples R China. Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Ping, JL (reprint author), Nanjing Univ, Dept Phys, Nanjing 210093, Peoples R China. NR 39 TC 11 Z9 13 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 NOV PY 2000 VL 62 IS 5 AR 054007 DI 10.1103/PhysRevC.62.054007 PG 6 WC Physics, Nuclear SC Physics GA 374XF UT WOS:000165369400015 ER PT J AU Tomsovic, S Johnson, MB Hayes, AC Bowman, JD AF Tomsovic, S Johnson, MB Hayes, AC Bowman, JD TI Statistical theory of parity nonconservation in compound nuclei SO PHYSICAL REVIEW C LA English DT Article ID MANY-PARTICLE SPECTRA; NEUTRON RESONANCES; NON-CONSERVATION; STRENGTH DISTRIBUTIONS; ENHANCEMENT; STATES; U-238; FLUCTUATIONS; SPECTROSCOPY; PHYSICS AB We present the first application of statistical spectroscopy to study the root-mean-square value of the parity nonconserving (PNC) interaction matrix element M determined experimentally by scattering longitudinally polarized neutrons from compound nuclei. Our effective PNC interaction consists of a standard two-body meson-exchange piece and a "doorway" term to account for 0 spin-flip excitations. Strength functions are calculated using realistic single-particle energies and a residual strong interaction adjusted to fit the experimental density of states for the targets, U-238 for A similar to 230 and Pd-104,Pd-105,Pd-106,Pd-108 for A similar to 100. Using the standard Desplanques-Donoghue-Holstein estimates of the weak PNC meson-nucleon coupling constants, we find that M is about a factor of 3 smaller than the experimental value for U-238 and about a factor of 1.7 smaller for Pd. The significance of this result for refining the empirical determination of the weak-coupling constants is discussed. C1 Washington State Univ, Dept Phys, Pullman, WA 99164 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Tomsovic, S (reprint author), Washington State Univ, Dept Phys, Pullman, WA 99164 USA. NR 55 TC 22 Z9 22 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 NOV PY 2000 VL 62 IS 5 AR 054607 DI 10.1103/PhysRevC.62.054607 PG 17 WC Physics, Nuclear SC Physics GA 374XF UT WOS:000165369400043 ER PT J AU Wheldon, C Walker, PM Chowdhury, P Shestakova, I D'Alarcao, R Ahmad, I Carpenter, MP Cullen, DM Janssens, RVF Khoo, TL Kondev, FG Lister, CJ Pearson, CJ Podolyak, Z Seweryniak, D Wiedenhoever, I AF Wheldon, C Walker, PM Chowdhury, P Shestakova, I D'Alarcao, R Ahmad, I Carpenter, MP Cullen, DM Janssens, RVF Khoo, TL Kondev, FG Lister, CJ Pearson, CJ Podolyak, Z Seweryniak, D Wiedenhoever, I TI Inelastic excitation of new high-spin yrast isomers in Ta-180 SO PHYSICAL REVIEW C LA English DT Article ID K-ISOMER; NEUTRON; NUCLEI AB For the first time, six-quasiparticle isomers have been observed in the meta-stable nucleus Ta-180(73)107. Two new high-spin isomers were populated following deep-inelastic reactions with a pulsed U-238(92) beam incident on a thick Hf-180(72) target. Out-of-beam gamma -ray events were collected using the Gammasphere germanium detector array. In addition to the known four-quasiparticle isomers, yrast K-pi = (22(-)) and K greater than or equal to 23 six-quasiparticle isomers have been observed with microsecond half-lives. These are the highest-spin isomers observed using the technique of deep-inelastic excitation. The assignments are compared to predictions made by BCS and Lipkin-Nogami multiquasiparticle calculations. C1 Univ Surrey, Dept Phys, Guildford GU2 7XH, Surrey, England. Univ Massachusetts, Lowell, MA 01854 USA. Argonne Natl Lab, Argonne, IL 60439 USA. Univ Liverpool, Oliver Lodge Lab, Dept Phys, Liverpool L69 7ZE, Merseyside, England. RP Univ Liverpool, Oliver Lodge Lab, Dept Phys, Liverpool L69 7ZE, Merseyside, England. RI Wheldon, Carl/F-9203-2013; Carpenter, Michael/E-4287-2015 OI Carpenter, Michael/0000-0002-3237-5734 NR 15 TC 15 Z9 15 U1 0 U2 0 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 NOV PY 2000 VL 62 IS 5 AR 057301 DI 10.1103/PhysRevC.62.057301 PG 4 WC Physics, Nuclear SC Physics GA 374XF UT WOS:000165369400069 ER PT J AU Abbott, B Abolins, M Abramov, V Acharya, BS Adam, I Adams, DL Adams, M Ahn, S Akimov, V Alves, GA Amos, N Anderson, EW Baarmand, MM Babintsev, VV Babukhadia, L Baden, A Baldin, B Banerjee, S Bantly, J Barberis, E Baringer, P Bartlett, JF Belyaev, A Beri, SB Bertram, I Bezzubov, VA Bhat, PC Bhatnagar, V Bhattacharjee, M Blazey, G Blessing, S Bloom, P Boehnlein, A Bojko, NI Borcherding, F Boswell, C Brandt, A Breedon, R Briskin, G Brock, R Bross, A Buchholz, D Burtovoi, VS Butler, JM Carvalho, W Casey, D Casilum, Z Castilla-Valdez, H Chakraborty, D Chan, KM Chekulaev, SV Chen, W Cho, DK Choi, S Chopra, S Choudhary, BC Christenson, JH Chung, M Claes, D Clark, AR Cobau, WG Cochran, J Coney, L Cooper, WE Coppage, D Cretsinger, C Cullen-Vidal, D Cummings, MAC Cutts, D Dahl, OI Davis, K De, K Del Signore, K Demarteau, M Denisov, D Denisov, SP Diehl, HT Diesburg, M Di Loreto, G Draper, P Ducros, Y Dudko, LV 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 Fatyga, MK Feher, S Fein, D Ferbel, T Fisk, HE Fisyak, Y Flattum, E Forden, GE Fortner, M Frame, KC Fuess, S Gallas, E Galyaev, AN Gartung, P Gavrilov, V Geld, TL Genik, RJ Genser, K Gerber, CE Gershtein, Y Gibbard, B Ginther, G Gobbi, B Gomez, B Gomez, G Goncharov, PI Solis, JLG Gordon, H Goss, LT Gounder, K Goussiou, A Graf, N Grannis, PD Green, DR Green, JA Greenlee, H Grinstein, S Grudberg, P Grunendahl, S Guglielmo, G Guida, JA Guida, JM Gupta, A Gurzhiev, SN Gutierrez, G Gutierrez, P Hadley, NJ Haggerty, H Hagopian, S Hagopian, V Hahn, KS Hall, RE Hanlet, P Hansen, S Hauptman, JM Hays, C Hebert, C Hedin, D Heinson, AP Heintz, U Hernandez-Montoya, R Heuring, T Hirosky, R Hobbs, JD Hoeneisen, B Hoftun, JS Hsieh, F Hu, T Ito, AS Jerger, SA Jesik, R Joffe-Minor, T Johns, K Johnson, M Jonckheere, A Jones, M Jostlein, H Jun, SY Kahn, S Karmanov, D Karmgard, D Kehoe, R Kim, SK Klima, B Klopfenstein, C Knuteson, B Ko, W Kohli, JM Koltick, D Kostritskiy, AV Kotcher, J Kotwal, AV Kozelov, AV Kozlovsky, EA Krane, J Krishnaswamy, MR Krzywdzinski, S Kubantsev, M Kuleshov, S Kulik, Y Kunori, S Landry, F Landsberg, G Leflat, A Li, J Li, QZ Lima, JGR Lincoln, D Linn, SL Linnemann, J Lipton, R Lu, JG Lucotte, A Lueking, L Maciel, AKA Madaras, RJ Madden, R Magana-Mendoza, L Manankov, V Mani, S Mao, HS Markeloff, R Marshall, T Martin, MI Martin, RD Mauritz, KM May, B Mayorov, AA McCarthy, R McDonald, J McKibben, T McKinley, J McMahon, T Melanson, HL Merkin, M Merritt, KW Miao, C Miettinen, H Mincer, A Mishra, CS Mokhov, N Mondal, NK Montgomery, HE Mostafa, M da Motta, H Nang, F Narain, M Narasimham, VS Narayanan, A Neal, HA Negret, JP Nemethy, P Norman, D Oesch, L Oguri, V Oshima, N Owen, D Padley, P Para, A Parashar, N Park, YM Partridge, R Parua, N Paterno, M Pawlik, B Perkins, J Peters, M Piegaia, R Piekarz, H Pischalnikov, Y Pope, BG Prosper, HB Protopopescu, S Qian, J Quintas, PZ Rajagopalan, S Ramirez, O Reay, NW Reucroft, S Rijssenbeek, M Rockwell, T Roco, M Rubinov, P Ruchti, R Rutherfoord, J Sanchez-Hernandez, A Santoro, A Sawyer, L Schamberger, RD Schellman, H Sculli, J Shabalina, E Shaffer, C Shankar, HC Shivpuri, RK Shpakov, D Shupe, M Sidwell, RA Singh, H Singh, JB Sirotenko, V Slattery, P Smith, E Smith, RP Snihur, R Snow, GR Snow, J Snyder, S Solomon, J Song, XF Sosebee, M Sotnikova, N Souza, M Stanton, NR Steinbruck, G Stephens, RW Stevenson, ML Stichelbaut, F Stoker, D Stolin, V Stoyanova, DA Strauss, M Streets, K Strovink, M Sznajder, A Tamburello, P Tarazi, J Tartaglia, M Thomas, TLT Thompson, J Toback, D Trippe, TG Tuts, PM Vaniev, V Varelas, N Varnes, EW Volkov, AA Vorobiev, AP Wahl, HD Warchol, J Watts, G Wayne, M Weerts, H White, A White, JT Wightman, JA Willis, S Wimpenny, SJ Wirjawan, JVD Womersley, J Wood, DR Yamada, R Yamin, P Yasuda, T Yepes, P Yip, K Yoshikawa, C Youssef, S Yu, J Yu, Y Zanabria, M Zhou, Z Zhu, ZH Zielinski, M Zieminska, D Zieminski, A Zutshi, V Zverev, EG Zylberstejn, A AF Abbott, B Abolins, M Abramov, V Acharya, BS Adam, I Adams, DL Adams, M Ahn, S Akimov, V Alves, GA Amos, N Anderson, EW Baarmand, MM Babintsev, VV Babukhadia, L Baden, A Baldin, B Banerjee, S Bantly, J Barberis, E Baringer, P Bartlett, JF Belyaev, A Beri, SB Bertram, I Bezzubov, VA Bhat, PC Bhatnagar, V Bhattacharjee, M Blazey, G Blessing, S Bloom, P Boehnlein, A Bojko, NI Borcherding, F Boswell, C Brandt, A Breedon, R Briskin, G Brock, R Bross, A Buchholz, D Burtovoi, VS Butler, JM Carvalho, W Casey, D Casilum, Z Castilla-Valdez, H Chakraborty, D Chan, KM Chekulaev, SV Chen, W Cho, DK Choi, S Chopra, S Choudhary, BC Christenson, JH Chung, M Claes, D Clark, AR Cobau, WG Cochran, J Coney, L Cooper, WE Coppage, D Cretsinger, C Cullen-Vidal, D Cummings, MAC Cutts, D Dahl, OI Davis, K De, K Del Signore, K Demarteau, M Denisov, D Denisov, SP Diehl, HT Diesburg, M Di Loreto, G Draper, P Ducros, Y Dudko, LV 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 Fatyga, MK Feher, S Fein, D Ferbel, T Fisk, HE Fisyak, Y Flattum, E Forden, GE Fortner, M Frame, KC Fuess, S Gallas, E Galyaev, AN Gartung, P Gavrilov, V Geld, TL Genik, RJ Genser, K Gerber, CE Gershtein, Y Gibbard, B Ginther, G Gobbi, B Gomez, B Gomez, G Goncharov, PI Solis, JLG Gordon, H Goss, LT Gounder, K Goussiou, A Graf, N Grannis, PD Green, DR Green, JA Greenlee, H Grinstein, S Grudberg, P Grunendahl, S Guglielmo, G Guida, JA Guida, JM Gupta, A Gurzhiev, SN Gutierrez, G Gutierrez, P Hadley, NJ Haggerty, H Hagopian, S Hagopian, V Hahn, KS Hall, RE Hanlet, P Hansen, S Hauptman, JM Hays, C Hebert, C Hedin, D Heinson, AP Heintz, U Hernandez-Montoya, R Heuring, T Hirosky, R Hobbs, JD Hoeneisen, B Hoftun, JS Hsieh, F Hu, T Ito, AS Jerger, SA Jesik, R Joffe-Minor, T Johns, K Johnson, M Jonckheere, A Jones, M Jostlein, H Jun, SY Kahn, S Karmanov, D Karmgard, D Kehoe, R Kim, SK Klima, B Klopfenstein, C Knuteson, B Ko, W Kohli, JM Koltick, D Kostritskiy, AV Kotcher, J Kotwal, AV Kozelov, AV Kozlovsky, EA Krane, J Krishnaswamy, MR Krzywdzinski, S Kubantsev, M Kuleshov, S Kulik, Y Kunori, S Landry, F Landsberg, G Leflat, A Li, J Li, QZ Lima, JGR Lincoln, D Linn, SL Linnemann, J Lipton, R Lu, JG Lucotte, A Lueking, L Maciel, AKA Madaras, RJ Madden, R Magana-Mendoza, L Manankov, V Mani, S Mao, HS Markeloff, R Marshall, T Martin, MI Martin, RD Mauritz, KM May, B Mayorov, AA McCarthy, R McDonald, J McKibben, T McKinley, J McMahon, T Melanson, HL Merkin, M Merritt, KW Miao, C Miettinen, H Mincer, A Mishra, CS Mokhov, N Mondal, NK Montgomery, HE Mostafa, M da Motta, H Nang, F Narain, M Narasimham, VS Narayanan, A Neal, HA Negret, JP Nemethy, P Norman, D Oesch, L Oguri, V Oshima, N Owen, D Padley, P Para, A Parashar, N Park, YM Partridge, R Parua, N Paterno, M Pawlik, B Perkins, J Peters, M Piegaia, R Piekarz, H Pischalnikov, Y Pope, BG Prosper, HB Protopopescu, S Qian, J Quintas, PZ Rajagopalan, S Ramirez, O Reay, NW Reucroft, S Rijssenbeek, M Rockwell, T Roco, M Rubinov, P Ruchti, R Rutherfoord, J Sanchez-Hernandez, A Santoro, A Sawyer, L Schamberger, RD Schellman, H Sculli, J Shabalina, E Shaffer, C Shankar, HC Shivpuri, RK Shpakov, D Shupe, M Sidwell, RA Singh, H Singh, JB Sirotenko, V Slattery, P Smith, E Smith, RP Snihur, R Snow, GR Snow, J Snyder, S Solomon, J Song, XF Sosebee, M Sotnikova, N Souza, M Stanton, NR Steinbruck, G Stephens, RW Stevenson, ML Stichelbaut, F Stoker, D Stolin, V Stoyanova, DA Strauss, M Streets, K Strovink, M Sznajder, A Tamburello, P Tarazi, J Tartaglia, M Thomas, TLT Thompson, J Toback, D Trippe, TG Tuts, PM Vaniev, V Varelas, N Varnes, EW Volkov, AA Vorobiev, AP Wahl, HD Warchol, J Watts, G Wayne, M Weerts, H White, A White, JT Wightman, JA Willis, S Wimpenny, SJ Wirjawan, JVD Womersley, J Wood, DR Yamada, R Yamin, P Yasuda, T Yepes, P Yip, K Yoshikawa, C Youssef, S Yu, J Yu, Y Zanabria, M Zhou, Z Zhu, ZH Zielinski, M Zieminska, D Zieminski, A Zutshi, V Zverev, EG Zylberstejn, A CA DO Collaboration TI Measurement of the W boson mass using large rapidity electrons SO PHYSICAL REVIEW D LA English DT Article ID TOP-QUARK MASS; CTEQ PARTON DISTRIBUTIONS; QED RADIATIVE-CORRECTIONS; CERN PBARP COLLIDER; P(P)OVER-BAR COLLISIONS; TRANSVERSE-MOMENTUM; FERMILAB-TEVATRON; STANDARD MODEL; D0 DETECTOR; NUCLEON SEA AB \We present a measurement of the W boson mass using data collected by the DO experiment at the Fermilab Tevatron during 1994-1995. We identify W bosons by their decays to ev final states where the electron is detected in a forward calorimeter. We extract the W boson mass M-W by fitting the transverse mass and transverse electron and neutrino momentum spectra from a sample of 11 089 W-->e nu decay candidates. We use a sample of 1687 dielectron events, mostly due to Z-->ee decays, to constrain our model of the detector response. Using the forward calorimeter data, we measure M-w=80.691+/-0.227 GeV. Combining the forward calorimeter measurements with our previously published central calorimeter results, we obtain M-W= 80.482 +/-0.091 GeV. C1 NYU, New York, NY 10003 USA. Univ Buenos Aires, Buenos Aires, DF, Argentina. Ctr Brasileiro Pesquisas Fis, LAFEX, Rio De Janeiro, Brazil. Univ Estado Rio de Janiero, Rio De Janeiro, Brazil. Inst High Energy Phys, Beijing 100039, Peoples R China. Univ Los Andes, Bogota, Colombia. Univ San Francisco, Quito, Ecuador. Univ Grenoble 1, Inst Sci Nucl, CNRS, IN2P3, Grenoble, France. CEA, Serv Phys Particules, DAPNIA, Saclay, France. Panjab Univ, Chandigarh 160014, India. Univ Delhi, Delhi 110007, India. Tata Inst Fundamental Res, Mumbai, India. Kyungsung Univ, Pusan 608736, South Korea. Seoul Natl Univ, Seoul, South Korea. CINVESTAV, Mexico City 14000, DF, Mexico. Inst Nucl Phys, Krakow, Poland. Inst Theoret & Expt Phys, Moscow 117259, Russia. Moscow State Univ, Moscow, Russia. Inst High Energy Phys, Protvino, Russia. Univ Lancaster, Lancaster, England. Univ Arizona, Tucson, AZ 85721 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Calif Davis, Davis, CA 95616 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. Purdue Univ, W Lafayette, IN 47907 USA. Iowa State Univ, Ames, IA 50011 USA. Univ Kansas, Lawrence, KS 66045 USA. Kansas State Univ, Manhattan, KS 66506 USA. Louisiana Tech Univ, Ruston, LA 71272 USA. Univ Maryland, College Pk, MD 20742 USA. Boston Univ, Boston, MA 02215 USA. Northeastern Univ, Boston, MA 02115 USA. Univ Michigan, Ann Arbor, MI 48109 USA. Michigan State Univ, E Lansing, MI 48824 USA. Univ Nebraska, Lincoln, NE 68588 USA. Columbia Univ, New York, NY 10027 USA. Univ Rochester, Rochester, NY 14627 USA. SUNY Stony Brook, Stony Brook, NY 11794 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. Langston Univ, Langston, OK 73050 USA. Univ Oklahoma, Norman, OK 73019 USA. Brown Univ, Providence, RI 02912 USA. Univ Texas, Arlington, TX 76019 USA. Texas A&M Univ, College Stn, TX 77843 USA. Rice Univ, Houston, TX 77005 USA. RP Abbott, B (reprint author), NYU, New York, NY 10003 USA. RI Sznajder, Andre/L-1621-2016; Shivpuri, R K/A-5848-2010; Gutierrez, Phillip/C-1161-2011; Dudko, Lev/D-7127-2012; Belyaev, Alexander/F-6637-2015; Kim, Sun Kee/G-2042-2015; Leflat, Alexander/D-7284-2012; Merkin, Mikhail/D-6809-2012; Yip, Kin/D-6860-2013; Kuleshov, Sergey/D-9940-2013; De, Kaushik/N-1953-2013; Oguri, Vitor/B-5403-2013; Alves, Gilvan/C-4007-2013; Chekulaev, Sergey/O-1145-2015 OI Sznajder, Andre/0000-0001-6998-1108; Dudko, Lev/0000-0002-4462-3192; Belyaev, Alexander/0000-0002-1733-4408; Kim, Sun Kee/0000-0002-0013-0775; Yip, Kin/0000-0002-8576-4311; Kuleshov, Sergey/0000-0002-3065-326X; De, Kaushik/0000-0002-5647-4489; NR 78 TC 26 Z9 26 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 NOV 1 PY 2000 VL 62 IS 9 AR 092006 DI 10.1103/PhysRevD.62.092006 PG 33 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 370EW UT WOS:000165111400010 ER PT J AU Abbott, B Abolins, M Abramov, V Acharya, BS Adams, DL Adams, M Alves, GA Amos, N Anderson, EW Baarmand, MM Babintsev, VV Babukhadia, L Baden, A Baldin, B Banerjee, S Bantly, J Barberis, E Baringer, P Bartlett, JF Bassler, U Bean, A Begel, M Belyaev, A Beri, SB Bernardi, G Bertram, I Besson, A Bezzubov, VA Bhat, PC Bhatnagar, V Bhattacharjee, M Blazey, G Blessing, S Boehnlein, A Bojko, NI Borcherding, F Brandt, A Breedon, R Briskin, G Brock, R Brooijmans, G Bross, A Buchholz, D Buehler, M Buescher, V Burtovoi, VS Butler, JM Canelli, F Carvalho, W Casey, D Casilum, Z Castilla-Valdez, H Chakraborty, D Chan, KM Chekulaev, SV Cho, DK Choi, S Chopra, S Choudhary, BC Christenson, JH Chung, M Claes, D Clark, AR Cochran, J Coney, L Connolly, B Cooper, WE Coppage, D Cummings, MAC Cutts, D Dahl, OI Davis, GA Davis, K De, K Del Signore, K Demarteau, M Demina, R Demine, P Denisov, D Denisov, SP Diehl, HT Diesburg, M Di Loreto, G Doulas, S Draper, P Ducros, Y Dudko, LV 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 Gartung, P Gavrilov, V Genik, RJ Genser, K Gerber, CE Gershtein, Y Gibbard, B Gilmartin, R Ginther, G Gomez, B Gomez, G Goncharov, PI Solis, JLG Gordon, H Goss, LT Gounder, K Goussiou, A Graf, N Grannis, PD Green, JA Greenlee, H Grinstein, S Grudberg, P Grunendahl, S Gupta, A Gurzhiev, SN Gutierrez, G Gutierrez, P Hadley, NJ Haggerty, H Hagopian, S Hagopian, V Hahn, KS Hall, RE Hanlet, P Hansen, S Hauptman, JM Hays, C Hebert, C Hedin, D Heinson, AP Heintz, U Heuring, T Hirosky, R Hobbs, JD Hoeneisen, B Hoftun, JS Ito, AS Jerger, SA Jesik, R Johns, K Johnson, M Jonckheere, A Jones, M Jostlein, H Juste, A Kahn, S Kajfasz, E Karmanov, D Karmgard, D Kehoe, R Kim, SK Klima, B Klopfenstein, C Knuteson, B Ko, W Kohli, JM Kostritskiy, AV Kotcher, J Kotwal, AV Kozelov, AV Kozlovsky, EA Krane, J Krishnaswamy, MR Krzywdzinski, S Kubantsev, M Kuleshov, S Kulik, Y Kunori, S Kuznetsov, V Landsberg, G Leflat, A Lehner, F Li, J Li, QZ Lima, JGR Lincoln, D Linn, SL Linnemann, J Lipton, R Lucotte, A Lueking, L Lundstedt, C Maciel, AKA Madaras, RJ Manankov, V Mani, S Mao, HS Marshall, T Martin, MI Martin, RD Mauritz, KM May, B Mayorov, AA McCarthy, R McDonald, J McMahon, T Melanson, HL Meng, XC Merkin, M Merritt, KW Miao, C Miettinen, H Mihalcea, D Mincer, A Mishra, CS Mokhov, N Mondal, NK Montgomery, HE Mostafa, M da Motta, H Nagy, E Nang, F Narain, M Narasimham, VS Neal, HA Negret, JP Negroni, S Norman, D Oesch, L Oguri, V Olivier, B Oshima, N Padley, P Pan, LJ Para, A Parashar, N Partridge, R Parua, N Paterno, M Patwa, A Pawlik, B Perkins, J Peters, M Piegaia, R Piekarz, H Pope, BG Popkov, E Prosper, HB Protopopescu, S Qian, J Quintas, PZ Raja, R Rajagopalan, S Ramberg, E Reay, NW Reucroft, S Rha, J Rijssenbeek, M Rockwell, T Roco, M Rubinov, P Ruchti, R Rutherfoord, J Santoro, A Sawyer, L Schamberger, RD Schellman, H Schwartzman, A Sculli, J Sen, N Shabalina, E Shankar, HC 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 Stevenson, ML Stichelbaut, F Stoker, D Stolin, V Stoyanova, DA Strauss, M Streets, K Strovink, M Stutte, L Sznajder, A Taylor, W Tentindo-Repond, S Thompson, J Toback, D Trippe, TG Turcot, AS Tuts, PM van Gemmeren, P Vaniev, V Van Kooten, R Varelas, N 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 Willis, S Wimpenny, SJ Wirjawan, JVD Womersley, J Wood, DR Yamada, R Yamin, P Yasuda, T Yip, K Youssef, S Yu, J Yu, Z Zanabria, M Zheng, H Zhou, Z Zhu, ZH Zielinski, M Zieminska, D Zieminski, A Zutshi, V Zverev, EG Zylberstejn, A AF Abbott, B Abolins, M Abramov, V Acharya, BS Adams, DL Adams, M Alves, GA Amos, N Anderson, EW Baarmand, MM Babintsev, VV Babukhadia, L Baden, A Baldin, B Banerjee, S Bantly, J Barberis, E Baringer, P Bartlett, JF Bassler, U Bean, A Begel, M Belyaev, A Beri, SB Bernardi, G Bertram, I Besson, A Bezzubov, VA Bhat, PC Bhatnagar, V Bhattacharjee, M Blazey, G Blessing, S Boehnlein, A Bojko, NI Borcherding, F Brandt, A Breedon, R Briskin, G Brock, R Brooijmans, G Bross, A Buchholz, D Buehler, M Buescher, V Burtovoi, VS Butler, JM Canelli, F Carvalho, W Casey, D Casilum, Z Castilla-Valdez, H Chakraborty, D Chan, KM Chekulaev, SV Cho, DK Choi, S Chopra, S Choudhary, BC Christenson, JH Chung, M Claes, D Clark, AR Cochran, J Coney, L Connolly, B Cooper, WE Coppage, D Cummings, MAC Cutts, D Dahl, OI Davis, GA Davis, K De, K Del Signore, K Demarteau, M Demina, R Demine, P Denisov, D Denisov, SP Diehl, HT Diesburg, M Di Loreto, G Doulas, S Draper, P Ducros, Y Dudko, LV 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 Gartung, P Gavrilov, V Genik, RJ Genser, K Gerber, CE Gershtein, Y Gibbard, B Gilmartin, R Ginther, G Gomez, B Gomez, G Goncharov, PI Solis, JLG Gordon, H Goss, LT Gounder, K Goussiou, A Graf, N Grannis, PD Green, JA Greenlee, H Grinstein, S Grudberg, P Grunendahl, S Gupta, A Gurzhiev, SN Gutierrez, G Gutierrez, P Hadley, NJ Haggerty, H Hagopian, S Hagopian, V Hahn, KS Hall, RE Hanlet, P Hansen, S Hauptman, JM Hays, C Hebert, C Hedin, D Heinson, AP Heintz, U Heuring, T Hirosky, R Hobbs, JD Hoeneisen, B Hoftun, JS Ito, AS Jerger, SA Jesik, R Johns, K Johnson, M Jonckheere, A Jones, M Jostlein, H Juste, A Kahn, S Kajfasz, E Karmanov, D Karmgard, D Kehoe, R Kim, SK Klima, B Klopfenstein, C Knuteson, B Ko, W Kohli, JM Kostritskiy, AV Kotcher, J Kotwal, AV Kozelov, AV Kozlovsky, EA Krane, J Krishnaswamy, MR Krzywdzinski, S Kubantsev, M Kuleshov, S Kulik, Y Kunori, S Kuznetsov, V Landsberg, G Leflat, A Lehner, F Li, J Li, QZ Lima, JGR Lincoln, D Linn, SL Linnemann, J Lipton, R Lucotte, A Lueking, L Lundstedt, C Maciel, AKA Madaras, RJ Manankov, V Mani, S Mao, HS Marshall, T Martin, MI Martin, RD Mauritz, KM May, B Mayorov, AA McCarthy, R McDonald, J McMahon, T Melanson, HL Meng, XC Merkin, M Merritt, KW Miao, C Miettinen, H Mihalcea, D Mincer, A Mishra, CS Mokhov, N Mondal, NK Montgomery, HE Mostafa, M da Motta, H Nagy, E Nang, F Narain, M Narasimham, VS Neal, HA Negret, JP Negroni, S Norman, D Oesch, L Oguri, V Olivier, B Oshima, N Padley, P Pan, LJ Para, A Parashar, N Partridge, R Parua, N Paterno, M Patwa, A Pawlik, B Perkins, J Peters, M Piegaia, R Piekarz, H Pope, BG Popkov, E Prosper, HB Protopopescu, S Qian, J Quintas, PZ Raja, R Rajagopalan, S Ramberg, E Reay, NW Reucroft, S Rha, J Rijssenbeek, M Rockwell, T Roco, M Rubinov, P Ruchti, R Rutherfoord, J Santoro, A Sawyer, L Schamberger, RD Schellman, H Schwartzman, A Sculli, J Sen, N Shabalina, E Shankar, HC 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 Stevenson, ML Stichelbaut, F Stoker, D Stolin, V Stoyanova, DA Strauss, M Streets, K Strovink, M Stutte, L Sznajder, A Taylor, W Tentindo-Repond, S Thompson, J Toback, D Trippe, TG Turcot, AS Tuts, PM van Gemmeren, P Vaniev, V Van Kooten, R Varelas, N 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 Willis, S Wimpenny, SJ Wirjawan, JVD Womersley, J Wood, DR Yamada, R Yamin, P Yasuda, T Yip, K Youssef, S Yu, J Yu, Z Zanabria, M Zheng, H Zhou, Z Zhu, ZH Zielinski, M Zieminska, D Zieminski, A Zutshi, V Zverev, EG Zylberstejn, A CA DO Collaboration TI Search for new physics in e mu X data at DO using SLEUTH: A quasi-model-independent search strategy for new physics SO PHYSICAL REVIEW D LA English DT Article ID DYNAMICAL SYMMETRY BREAKING; PRODUCTION CROSS-SECTION; TOP-QUARK SEARCH; P(P)OVER-BAR COLLISIONS; SUPERSYMMETRY; FERMILAB; NEUTRALINOS; CHARGINOS; ENERGY; DECAYS AB We present a quasi-model-independent search for the physics responsible for electroweak symmetry breaking. We define final states to be studied, and construct a rule that identifies a set of relevant variables for any particular final state. A new algorithm ("SLEUTH") searches for regions of excess in those variables and quantifies the significance of any detected excess. After demonstrating the sensitivity of the method, we apply it to the semi-inclusive channel e muX collected in 108 pb(-1) of p(p) over bar collisions at roots=1.8 TeV at the DO experiment during 1992-1996 at the Fermilab Tevatron. We find no evidence of new high p(T) physics in this sample. C1 NYU, New York, NY 10003 USA. 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, Prague, Czech Republic. Acad Sci Czech Republ, Inst Phys, Prague, Czech Republic. Univ San Francisco, Quito, Ecuador. Univ Grenoble 1, Inst Sci Nucl, CNRS, IN2P3, Grenoble, France. Univ Mediterranee, CPPM, CNRS, IN2P3, Marseille, France. Univ Paris 06, LPNHE, CNRS, IN2P3, Paris, France. Univ Paris 07, LPNHE, CNRS, IN2P3, Paris, France. CEA, Serv Phys Particules, DAPNIA, Saclay, France. 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 Nijmegen, NIKHEF, Nijmegen, Netherlands. Inst Nucl Phys, Krakow, Poland. Inst Theoret & Expt Phys, Moscow 117259, Russia. Moscow State Univ, Moscow, Russia. Inst High Energy Phys, Protvino, Russia. Univ Lancaster, Lancaster, England. Univ Arizona, Tucson, AZ 85721 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Calif Davis, Davis, CA 95616 USA. Calif State Univ Fresno, Fresno, CA 93740 USA. Univ Calif Irvine, Irvine, CA 92697 USA. Univ Calif Riverside, Riverside, CA 92521 USA. Florida State Univ, Tallahassee, FL 32306 USA. Univ Hawaii, Honolulu, HI 96822 USA. 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. Rice Univ, Houston, TX 77005 USA. Univ Washington, Seattle, WA 98195 USA. RP Abbott, B (reprint author), NYU, New York, NY 10003 USA. RI Belyaev, Alexander/F-6637-2015; Kim, Sun Kee/G-2042-2015; Chekulaev, Sergey/O-1145-2015; Sznajder, Andre/L-1621-2016; Canelli, Florencia/O-9693-2016; Oguri, Vitor/B-5403-2013; Peters, Michael/B-4973-2009; Alves, Gilvan/C-4007-2013; Santoro, Alberto/E-7932-2014; Shivpuri, R K/A-5848-2010; Gutierrez, Phillip/C-1161-2011; Dudko, Lev/D-7127-2012; Leflat, Alexander/D-7284-2012; Merkin, Mikhail/D-6809-2012; Yip, Kin/D-6860-2013; Kuleshov, Sergey/D-9940-2013; De, Kaushik/N-1953-2013 OI Belyaev, Alexander/0000-0002-1733-4408; Kim, Sun Kee/0000-0002-0013-0775; Sznajder, Andre/0000-0001-6998-1108; Canelli, Florencia/0000-0001-6361-2117; Dudko, Lev/0000-0002-4462-3192; Yip, Kin/0000-0002-8576-4311; Kuleshov, Sergey/0000-0002-3065-326X; De, Kaushik/0000-0002-5647-4489 NR 34 TC 23 Z9 23 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 NOV 1 PY 2000 VL 62 IS 9 AR 092004 DI 10.1103/PhysRevD.62.092004 PG 19 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 370EW UT WOS:000165111400008 ER PT J AU Albright, CH Barr, SM AF Albright, CH Barr, SM TI Construction of a minimal Higgs SO(10) supersymmetric grand unified model SO PHYSICAL REVIEW D LA English DT Article ID ATMOSPHERIC NEUTRINO OSCILLATIONS; LEPTON MASSES; FERMION MASSES; GAUGE-MODEL; SOLAR; QUARK; UNIFICATION; PUZZLE; MATRIX; MATTER AB A full account is given of the procedure used by the authors to construct an SO(10) supersymmetric grand unified model of the fermion mass matrices. Various features of the model which gives remarkably accurate results for the quark and lepton masses and mixings were presented earlier in separate publications. The construction of the matrices is first discussed in the framework of effective operators, from which one naturally obtains the maximal nu (mu)- nu (tau) mixing, while the small angle or maximal mixing solutions for the solar neutrinos depend upon the nature of the Majorana matrix. A set of Higgs and fermion superfields is then introduced from which the Higgs and Yukawa superpotentials uniquely give the structure of the mass matrices previously obtained. The right-handed Majorana matrix arises from one Higgs field coupling to several pairs of superheavy conjugate neutrino singlets. For the simple version considered, 10 input parameters accurately yield the 20 masses and mixings of the quarks and leptons, and the 3 masses of the right-handed neutrinos. C1 No Illinois Univ, Dept Phys, De Kalb, IL 60115 USA. Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Delaware, Bartol Res Inst, Newark, DE 19716 USA. RP Albright, CH (reprint author), No Illinois Univ, Dept Phys, De Kalb, IL 60115 USA. EM albright@fnal.gov; smbarr@bartol.udel.edu OI Albright, Carl/0000-0002-2252-6359 NR 54 TC 64 Z9 64 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 NOV 1 PY 2000 VL 62 IS 9 AR 093008 DI 10.1103/PhysRevD.62.093008 PG 20 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 370EW UT WOS:000165111400019 ER PT J AU Allen, TJ Olsson, MG Veseli, S AF Allen, TJ Olsson, MG Veseli, S TI From scalar to string confinement SO PHYSICAL REVIEW D LA English DT Article ID SPIN STRUCTURE; RELATIVISTIC CORRECTIONS; QUANTUM CHROMODYNAMICS; QUARKONIUM SPECTRUM; BOUND-STATES; FLUX TUBES; ANTIQUARK; QCD; CHARMONIUM; DERIVATION AB We outline a connection between scalar quark confinement, a phenomenologically successful concept heretofore lacking fundamental justification, and QCD. Although scalar confinement does not follow from QCD, there is an interesting and close relationship between them. We develop a simple model intermediate between scaler confinement and the QCD string for illustrative purposes. Finally, we find analytically the bound state spectrum of the light degrees of freedom for a spinless, massless quark in scalar, time-component vector, and string confinement through semi-classical quantization. C1 SUNY Coll Technol Utica Rome, Inst Technol, Sch Arts & Sci, Utica, NY 13504 USA. Univ Wisconsin, Dept Phys, Madison, WI 53706 USA. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. RP Hobart & William Smith Coll, Dept Phys, Geneva, NY 14456 USA. NR 36 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 2470-0010 EI 2470-0029 J9 PHYS REV D JI Phys. Rev. D PD NOV 1 PY 2000 VL 62 IS 9 AR 094021 DI 10.1103/PhysRevD.62.094021 PG 9 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 370EW UT WOS:000165111400059 ER PT J AU Ammar, R Baringer, P Brabant, P Bean, A Besson, D Bull, H Davis, R Holliday, J Kotov, S Kravchenko, I Kwak, N Robertson, I Stutz, R Zhao, X Anderson, S Frolov, VV Kubota, Y Lee, SJ Mahapatra, R O'Neill, JJ Poling, R Riehle, T Smith, A Ahmed, S Alam, MS Athar, SB Jian, L Ling, L Mahmood, AH Saleem, M Timm, S Wappler, F Anastassov, A Duboscq, JE Gan, KK Gwon, C Hart, T Honscheid, K Kagan, H Kass, R Lorenc, J Schwarthoff, H von Toerne, E Zoeller, MM Richichi, SJ Severini, H Skubic, P Undrus, A Bishai, M Chen, S Fast, J Hinson, JW Lee, J Menon, N Miller, DH Shibata, EI Shipsey, IPJ Kwon, Y Lyon, AL Thorndike, EH Jessop, CP Lingel, K Marsiske, H Perl, ML Savinov, V Ugolini, D Zhou, X Coan, TE Fadeyev, V Korolkov, I Maravin, Y Narsky, I Stroynowski, R Ye, J Wlodek, T Artuso, M Ayad, R Dambasuren, E Kopp, S Majumder, G Moneti, GC Mountain, R Schuh, S Skwarnicki, T Stone, S Titov, A Viehhauser, G Wang, JC Wolf, A Wu, J Csorna, SE McLean, KW Marka, S Xu, Z Godang, R Kinoshita, K Lai, IC Pomianowski, P Schrenk, S Bonvicini, G Cinabro, D Greene, R Perera, LP Zhou, GJ Chan, S Eigen, G Lipeles, E Schmidtler, M Shapiro, A Sun, WM Urheim, J Weinstein, AJ Wurthwein, F Jaffe, DE Masek, G Paar, HP Potter, EM Prell, S Sharma, V Asner, DM Eppich, A Gronberg, J Hill, TS Lange, DJ Morrison, RJ Nelson, TK Richman, JD Briere, RA Behrens, BH Ford, WT Gritsan, A Krieg, H Roy, J Smith, JG Alexander, JP Baker, R Bebek, C Berger, BE Berkelman, K Blanc, F Boisvert, V Cassel, DG Dickson, M Drell, PS Ecklund, KM Ehrlich, R Foland, AD Gaidarev, P Gibbons, L Gittelman, B Gray, SW Hartill, DL Heltsley, BK Hopman, PI Jones, CD Kreinick, DL Lee, T Liu, Y Meyer, TO Mistry, NB Ng, CR Nordberg, E Patterson, JR Peterson, D Riley, D Thayer, JG Thies, PG Valant-Spaight, B Warburton, A Avery, P Lohner, M Prescott, C Rubiera, AI Yelton, J Zheng, J Brandenburg, G Ershov, A Gao, YS Kim, DYJ Wilson, R Browder, TE Li, Y Rodriguez, JL Yamamoto, H Bergfeld, T Eisenstein, BI Ernst, J Gladding, GE Gollin, GD Hans, RM Johnson, E Karliner, I Marsh, MA Palmer, M Plager, C Sedlack, C Selen, M Thaler, JJ Williams, J Edwards, KW Janicek, R Patel, PM Sadoff, AJ AF Ammar, R Baringer, P Brabant, P Bean, A Besson, D Bull, H Davis, R Holliday, J Kotov, S Kravchenko, I Kwak, N Robertson, I Stutz, R Zhao, X Anderson, S Frolov, VV Kubota, Y Lee, SJ Mahapatra, R O'Neill, JJ Poling, R Riehle, T Smith, A Ahmed, S Alam, MS Athar, SB Jian, L Ling, L Mahmood, AH Saleem, M Timm, S Wappler, F Anastassov, A Duboscq, JE Gan, KK Gwon, C Hart, T Honscheid, K Kagan, H Kass, R Lorenc, J Schwarthoff, H von Toerne, E Zoeller, MM Richichi, SJ Severini, H Skubic, P Undrus, A Bishai, M Chen, S Fast, J Hinson, JW Lee, J Menon, N Miller, DH Shibata, EI Shipsey, IPJ Kwon, Y Lyon, AL Thorndike, EH Jessop, CP Lingel, K Marsiske, H Perl, ML Savinov, V Ugolini, D Zhou, X Coan, TE Fadeyev, V Korolkov, I Maravin, Y Narsky, I Stroynowski, R Ye, J Wlodek, T Artuso, M Ayad, R Dambasuren, E Kopp, S Majumder, G Moneti, GC Mountain, R Schuh, S Skwarnicki, T Stone, S Titov, A Viehhauser, G Wang, JC Wolf, A Wu, J Csorna, SE McLean, KW Marka, S Xu, Z Godang, R Kinoshita, K Lai, IC Pomianowski, P Schrenk, S Bonvicini, G Cinabro, D Greene, R Perera, LP Zhou, GJ Chan, S Eigen, G Lipeles, E Schmidtler, M Shapiro, A Sun, WM Urheim, J Weinstein, AJ Wurthwein, F Jaffe, DE Masek, G Paar, HP Potter, EM Prell, S Sharma, V Asner, DM Eppich, A Gronberg, J Hill, TS Lange, DJ Morrison, RJ Nelson, TK Richman, JD Briere, RA Behrens, BH Ford, WT Gritsan, A Krieg, H Roy, J Smith, JG Alexander, JP Baker, R Bebek, C Berger, BE Berkelman, K Blanc, F Boisvert, V Cassel, DG Dickson, M Drell, PS Ecklund, KM Ehrlich, R Foland, AD Gaidarev, P Gibbons, L Gittelman, B Gray, SW Hartill, DL Heltsley, BK Hopman, PI Jones, CD Kreinick, DL Lee, T Liu, Y Meyer, TO Mistry, NB Ng, CR Nordberg, E Patterson, JR Peterson, D Riley, D Thayer, JG Thies, PG Valant-Spaight, B Warburton, A Avery, P Lohner, M Prescott, C Rubiera, AI Yelton, J Zheng, J Brandenburg, G Ershov, A Gao, YS Kim, DYJ Wilson, R Browder, TE Li, Y Rodriguez, JL Yamamoto, H Bergfeld, T Eisenstein, BI Ernst, J Gladding, GE Gollin, GD Hans, RM Johnson, E Karliner, I Marsh, MA Palmer, M Plager, C Sedlack, C Selen, M Thaler, JJ Williams, J Edwards, KW Janicek, R Patel, PM Sadoff, AJ CA CLEO Collaboration TI Measurement of the product branching fraction B(c ->Theta X-c) x B(Theta(c)->Lambda X) SO PHYSICAL REVIEW D LA English DT Article ID CLEO-II DETECTOR; BARYON PRODUCTION; DECAY AB Based on a high statistics e(+)e(-) --> c (c) over bar data sample, we report on the inclusive rate for charmed baryons to decay into Lambda particles using charm-event tagging. We select e(+)e(-) --> c (c) over bar events which have a clear anti-charm tag and measure the h content in the hemisphere opposite the tag (charge conjugate modes are implicit). This allows us to determine the product branching fraction B-Lambda = B(c --> Theta X-c) x B(Theta (c) --> LambdaX), where Theta (c) represents a sum over all charmed baryons produced in e(+)e(-) fragmentation at roots= 10.5 GeV, given our specific tags. We obtain B-Lambda =(1.87+/-0.03+/-0.33)%. C1 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. So Methodist Univ, Dallas, TX 75275 USA. Syracuse Univ, Syracuse, NY 13244 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 Hawaii Manoa, Honolulu, HI 96822 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 Texas Pan Amer, Edinburg, TX 78539 USA. Yonsei Univ, Seoul 120749, South Korea. Univ Cincinnati, Cincinnati, OH 45221 USA. RP Ammar, R (reprint author), Univ Kansas, Lawrence, KS 66045 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 NR 16 TC 1 Z9 1 U1 1 U2 3 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD NOV 1 PY 2000 VL 62 IS 9 AR 092007 PG 12 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 370EW UT WOS:000165111400011 ER PT J AU Arkani-Hamed, N Cheng, HC Dobrescu, BA Hall, LJ AF Arkani-Hamed, N Cheng, HC Dobrescu, BA Hall, LJ TI Self-breaking of the standard model gauge symmetry SO PHYSICAL REVIEW D LA English DT Article ID TOP-QUARK MASS; INFRARED FIXED-POINT; DIMENSIONS; UNIFICATION; PREDICTIONS; MILLIMETER; HIERARCHY AB If the gauge fields of the standard model propagate in TeV-size extra dimensions, they rapidly become strongly coupled and can form scalar bound states of quarks and leptons. If the quarks and leptons of the third generation propagate in 6 or 8 dimensions, we argue that the most tightly bound scalar is a composite of top quarks, having the quantum numbers of the Higgs doublet and a large coupling to the top quark. In the case where the gauge bosons propagate in a bulk of a certain volume, this composite Higgs doublet can successfully trigger electroweak symmetry breaking. The mass of the top quark is correctly predicted to within 20%, without the need to add a fundamental Yukawa interaction, and the Higgs boson mass is predicted to lie in the range 165-230 GeV. In addition to the Higgs boson, there may be a few other scalar composites sufficiently light to be observed at upcoming collider experiments. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Theoret Phys Grp, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Chicago, Enrico Fermi Inst, Chicago, IL 60637 USA. Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. RP Arkani-Hamed, N (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Theoret Phys Grp, Berkeley, CA 94720 USA. NR 32 TC 88 Z9 88 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 NOV 1 PY 2000 VL 62 IS 9 AR 096006 DI 10.1103/PhysRevD.62.096006 PG 12 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 370EW UT WOS:000165111400100 ER PT J AU Aurenche, P Gelis, F Zaraket, H AF Aurenche, P Gelis, F Zaraket, H TI Landau-Pomeranchuk-Migdal effect in thermal field theory SO PHYSICAL REVIEW D LA English DT Article ID QUARK-GLUON PLASMA; PHOTON PRODUCTION-RATE; RESUMMED PERTURBATION-THEORY; HOT GAUGE-THEORIES; FINITE-TEMPERATURE; LADDER GRAPHS; SOFT DILEPTONS; LIGHT-CONE; QCD; BREMSSTRAHLUNG AB In recent studies, the production rate of photons or lepton pairs by a quark gluon plasma has been found to be enhanced due to collinear singularities. This enhancement pattern is very dependent on rather strict collinearity conditions between the photon and the quark momenta. It was estimated by neglecting the collisional width of quasiparticles. In this paper, we study the modifications of this collinear enhancement when we take into account the possibility for the quarks to have a finite mean free path. Assuming a mean free path of order [g(2)Tln(1/g)](-1), we find that only low invariant mass photons are affected. The region where collision effects are important can be interpreted as the region where the Landau-Pomeranchuk-Migdal effect plays a role in thermal photon production by bremsstrahlung. It is found that this effect modifies the spectrum of very energetic photons as well. Based on these results and on a previous work on infrared singularities, we end this paper with a reasonable physical picture for photon production by a quark gluon plasma that should be useful to set directions for future technical developments. C1 Univ Savoie, CNRS, UMR 5108, LAPTH,Lab Phys Theor, F-74941 Annecy Le Vieux, France. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Aurenche, P (reprint author), Univ Savoie, CNRS, UMR 5108, LAPTH,Lab Phys Theor, BP110, F-74941 Annecy Le Vieux, France. NR 45 TC 65 Z9 65 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 NOV 1 PY 2000 VL 62 IS 9 AR 096012 DI 10.1103/PhysRevD.62.096012 PG 15 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 370EW UT WOS:000165111400106 ER PT J AU Berger, EL Klasen, M Tait, TMP AF Berger, EL Klasen, M Tait, TMP TI Next-to-leading order supersymmetric QCD predictions for associated production of gauginos and gluinos SO PHYSICAL REVIEW D LA English DT Article ID DEEP-INELASTIC SCATTERING; HADRON-HADRON-COLLISIONS; MEDIATED SUSY BREAKING; GRAND UNIFIED THEORIES; HEAVY-QUARK PRODUCTION; PAIR PRODUCTION; GAUGE-THEORIES; COLLIDERS; SEARCH; SCALE AB We present complete results of a next-to-leading order calculation of the production of gaugino-like charginos ((x) over tilde (+/-)) and neutralinos ((x) over tilde (0)) in association with gluinos ((g) over tilde) at hadron colliders, including the strong corrections from the exchange of colored particles and sparticles. Adopting a variety of models for the sparticle mass spectrum, including typical supergravity (SUGRA) models and a light gluino model, we provide predictions for total and differential cross sections at the energies of the Fermilab Tevatron and CERN Large Hadron Collider (LHC). C1 Argonne Natl Lab, Div High Energy Phys, Argonne, IL 60439 USA. Univ Hamburg, Inst Theoret Phys 2, D-2000 Hamburg, Germany. RP Argonne Natl Lab, Div High Energy Phys, Argonne, IL 60439 USA. NR 64 TC 29 Z9 29 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0010 EI 2470-0029 J9 PHYS REV D JI Phys. Rev. D PD NOV 1 PY 2000 VL 62 IS 9 AR 095014 DI 10.1103/PhysRevD.62.095014 PG 38 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 370EW UT WOS:000165111400094 ER PT J AU Bergfeld, T Eisenstein, BI Ernst, J Gladding, GE Gollin, GD Hans, RM Johnson, E Karliner, I Marsh, MA Palmer, M Plager, C Sedlack, C Selen, M Thaler, JJ Williams, J Edwards, KW Janicek, R Patel, PM Sadoff, AJ Ammar, R Bean, A Besson, D Davis, R Kwak, N 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 Thorndike, EH Jessop, CP Marsiske, H Perl, ML Savinov, V Zhou, X Coan, TE Fadeyev, V Maravin, Y Narsky, I Stroynowski, R Ye, J Wlodek, T Artuso, M Ayad, R Boulahouache, 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 Marka, S Xu, Z Godang, R Kinoshita, K Lai, IC Schrenk, S Bonvicini, G Cinabro, D McGee, S Perera, LP 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 Sharma, V Asner, DM Eppich, A Hill, TS Morrison, RJ Briere, RA Chen, GP Behrens, BH Ford, WT Gritsan, A Roy, J Smith, JG Alexander, JP Baker, R Bebek, C Berger, BE Berkelman, K Blanc, F Boisvert, V Cassel, DG Dickson, M Drell, PS Ecklund, KM Ehrlich, R Foland, AD Gaidarev, P Gibbons, L Gittelman, B Gray, SW Hartill, DL Heltsley, BK Hopman, PI Jones, CD Kreinick, DL Lohner, M Magerkurth, A Meyer, TO Mistry, NB Nordberg, E Patterson, JR Peterson, D Riley, D Thayer, JG Urner, D Valant-Spaight, B Warburton, A Avery, P Prescott, C Rubiera, AI Yelton, J Zheng, J Brandenburg, G Ershov, A Gao, YS Kim, DYJ Wilson, R Browder, TE Li, Y Rodriguez, JL Yamamoto, H AF Bergfeld, T Eisenstein, BI Ernst, J Gladding, GE Gollin, GD Hans, RM Johnson, E Karliner, I Marsh, MA Palmer, M Plager, C Sedlack, C Selen, M Thaler, JJ Williams, J Edwards, KW Janicek, R Patel, PM Sadoff, AJ Ammar, R Bean, A Besson, D Davis, R Kwak, N 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 Thorndike, EH Jessop, CP Marsiske, H Perl, ML Savinov, V Zhou, X Coan, TE Fadeyev, V Maravin, Y Narsky, I Stroynowski, R Ye, J Wlodek, T Artuso, M Ayad, R Boulahouache, 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 Marka, S Xu, Z Godang, R Kinoshita, K Lai, IC Schrenk, S Bonvicini, G Cinabro, D McGee, S Perera, LP 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 Sharma, V Asner, DM Eppich, A Hill, TS Morrison, RJ Briere, RA Chen, GP Behrens, BH Ford, WT Gritsan, A Roy, J Smith, JG Alexander, JP Baker, R Bebek, C Berger, BE Berkelman, K Blanc, F Boisvert, V Cassel, DG Dickson, M Drell, PS Ecklund, KM Ehrlich, R Foland, AD Gaidarev, P Gibbons, L Gittelman, B Gray, SW Hartill, DL Heltsley, BK Hopman, PI Jones, CD Kreinick, DL Lohner, M Magerkurth, A Meyer, TO Mistry, NB Nordberg, E Patterson, JR Peterson, D Riley, D Thayer, JG Urner, D Valant-Spaight, B Warburton, A Avery, P Prescott, C Rubiera, AI Yelton, J Zheng, J Brandenburg, G Ershov, A Gao, YS Kim, DYJ Wilson, R Browder, TE Li, Y Rodriguez, JL Yamamoto, H CA CLEO Collaboration TI Search for decays of B-0 mesons into pairs of leptons: B-0 -> e(+)e(-), B-0 ->mu(+)mu(-), and B-0 -> e(+/-)mu(-/+) SO PHYSICAL REVIEW D LA English DT Article ID 2-HIGGS-DOUBLET MODEL; CP ASYMMETRIES; DETECTOR; LEPTOQUARKS AB We search for the decay of the B-0 meson into a pair of leptons in the suppressed channels B-0-->e(+)e(-), B-0-->mu (+)mu (-) and in the lepton number violating channel B-0-->e(+/-)mu (-/+) in a sample of 9.7 x 10(6) B(B) over bar pairs recorded corded by CLEO detector. No signal is found, and the following upper limits on the branching fractions are established: B(B-0-->e(+)e(-))<8.3 x 10(-7), B(B-0-->mu (+)mu (-))<6.1 x 10(-7), B(B-0-->e(+/-)mu (-/+))<15 x 10(-7) at 90% confidence level. A new lower limit on the Pati-Salam leptoquark mass M-LQ>27 TeV is established at 90% confidence level. C1 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. 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 Hawaii Manoa, Honolulu, HI 96822 USA. Univ Cincinnati, Cincinnati, OH 45221 USA. MIT, Cambridge, MA 02139 USA. RP Bergfeld, T (reprint author), Univ Illinois, Urbana, IL 61801 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 NR 21 TC 20 Z9 20 U1 1 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD NOV 1 PY 2000 VL 62 IS 9 AR 091102 DI 10.1103/PhysRevD.62.091102 PG 5 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 370EW UT WOS:000165111400002 ER PT J AU Boer, D AF Boer, D TI Double transverse spin asymmetries in vector boson production SO PHYSICAL REVIEW D LA English DT Article ID DRELL-YAN PROCESS; ODD PARTON DISTRIBUTIONS; MOMENTUM DISTRIBUTIONS; E(+)E(-) ANNIHILATION; HADRON-COLLISIONS; DIMUON PRODUCTION; HARD-SCATTERING; CROSS-SECTION; FRAGMENTATION; RESUMMATION AB We investigate a helicity non-flip double transverse spin asymmetry in vector boson production in hadron-hadron scattering, which was first considered by Ralston and Soper at the tree level. It does not involve transversity functions and in principle also arises in W-boson production for which we present the expressions. The asymmetry requires observing the transverse momentum of the vector boson, but it is not suppressed by explicit inverse powers of a large energy scale. However, as we will show, inclusion of Sudakov factors causes suppression of the asymmetry, which increases with energy. Moreover, the asymmetry is shown to be approximately proportional to x(1)g(1)(x(1))x(2)(g) over bar (1)(x(2)), which gives rise to additional suppression at small values of the light cone momentum fractions. This implies that it is negligible for Z or W production and is mainly of interest for gamma* at low energies. We also compare the asymmetry with other types of double transverse spin asymmetries and discuss how to disentangle them. C1 Brookhaven Natl Lab, RIKEN BNL Res Ctr, Upton, NY 11973 USA. RP Boer, D (reprint author), Brookhaven Natl Lab, RIKEN BNL Res Ctr, Upton, NY 11973 USA. RI Boer, Daniel/B-3493-2015 OI Boer, Daniel/0000-0003-0985-4662 NR 47 TC 19 Z9 19 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD NOV 1 PY 2000 VL 62 IS 9 AR 094029 DI 10.1103/PhysRevD.62.094029 PG 9 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 370EW UT WOS:000165111400067 ER PT J AU Brown, HN Bunce, G Carey, RM Cushman, P Danby, GT Debevec, PT Deng, H Deninger, W Dhawan, SK Druzhinin, VP Duong, L Earle, W Efstathiadis, E Fedotovich, GV Farley, FJM Giron, S Gray, F Grosse-Perdekamp, M Grossmann, A Haeberlen, U Hare, MF Hazen, ES Hertzog, DW Hughes, VW Iwasaki, M Jungmann, K Kawall, D Kawamura, M Khazin, BI Kindem, J Krienen, F Kronkvist, I Larsen, R Lee, YY Logashenko, I McNabb, R Meng, W Mi, J Miller, JP Morse, WM Onderwater, CJG Orlov, Y Ozben, C Polly, C Pai, C Paley, JM Pretz, J Prigl, R Putlitz, GZ Redin, SI Rind, O Roberts, BL Ryskulov, N Sedykh, S Semertzidis, YK Shatunov, YM Solodov, E Sossong, M Steinmetz, A Sulak, LR Timmermans, C Trofimov, A Urner, D von Walter, P Warburton, D Winn, D Yamamoto, A Zimmerman, D AF Brown, HN Bunce, G Carey, RM Cushman, P Danby, GT Debevec, PT Deng, H Deninger, W Dhawan, SK Druzhinin, VP Duong, L Earle, W Efstathiadis, E Fedotovich, GV Farley, FJM Giron, S Gray, F Grosse-Perdekamp, M Grossmann, A Haeberlen, U Hare, MF Hazen, ES Hertzog, DW Hughes, VW Iwasaki, M Jungmann, K Kawall, D Kawamura, M Khazin, BI Kindem, J Krienen, F Kronkvist, I Larsen, R Lee, YY Logashenko, I McNabb, R Meng, W Mi, J Miller, JP Morse, WM Onderwater, CJG Orlov, Y Ozben, C Polly, C Pai, C Paley, JM Pretz, J Prigl, R Putlitz, GZ Redin, SI Rind, O Roberts, BL Ryskulov, N Sedykh, S Semertzidis, YK Shatunov, YM Solodov, E Sossong, M Steinmetz, A Sulak, LR Timmermans, C Trofimov, A Urner, D von Walter, P Warburton, D Winn, D Yamamoto, A Zimmerman, D TI Improved measurement of the positive muon anomalous magnetic moment SO PHYSICAL REVIEW D LA English DT Article AB A new measurement of the positive muon's anomalous magnetic moment has been made at the Brookhaven Alternating Gradient Synchrotron using the direct injection of polarized muons into the superferric storage ring. The angular frequency difference omega (a) between the angular spin precession frequency omega (s) and the angular orbital frequency omega (c) is measured as well as the free proton MMR frequency omega (p). These determine R = omega (a)/omega (p) = 3.707 201(19) x 10(-3). With mu (mu)/mu (p) = 3.183 345 39(10) this gives a(mu+) = 11 659 191(59) x 10-(10) (+/-5 ppm), in good agreement with the previous CERN and BNL measurements for mu (+) and mu (-), and with the standard model prediction. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. Boston Univ, Dept Phys, Boston, MA 02215 USA. Budker Inst Nucl Phys, Novosibirsk 630090, Russia. Cornell Univ, Newman Lab, Ithaca, NY 14853 USA. Fairfield Univ, Fairfield, CT 06430 USA. Univ Heidelberg, Inst Phys, D-69120 Heidelberg, Germany. Univ Illinois, Dept Phys, Urbana, IL 61801 USA. Max Planck Inst Med Forsch, D-69120 Heidelberg, Germany. High Energy Accelerator Res Org, KEK, Tsukuba, Ibaraki 3050801, Japan. Univ Minnesota, Dept Phys, Minneapolis, MN 55455 USA. Tokyo Inst Technol, Tokyo 152, Japan. Yale Univ, Dept Phys, New Haven, CT 06511 USA. RP Brown, HN (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. RI Jungmann, Klaus/A-7142-2010; jungmann, klaus/H-1581-2013; Semertzidis, Yannis K./N-1002-2013; Logashenko, Ivan/A-3872-2014; Iwasaki, Masahiko/M-8433-2014 OI jungmann, klaus/0000-0003-0571-4072; Iwasaki, Masahiko/0000-0002-3460-9469 NR 16 TC 98 Z9 98 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 NOV 1 PY 2000 VL 62 IS 9 AR 091101 DI 10.1103/PhysRevD.62.091101 PG 4 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 370EW UT WOS:000165111400001 ER PT J AU Buchmann, AJ Lebed, RF AF Buchmann, AJ Lebed, RF TI Large N-c, constituent quarks, and N, Delta charge radii SO PHYSICAL REVIEW D LA English DT Article ID BARYON MAGNETIC-MOMENTS; SYMMETRY-BREAKING; 1/N-C EXPANSION; MASS SPLITTINGS; L=1 BARYONS; QCD; MODEL; DECAYS; PARAMETRIZATION AB We show how one may define baryon constituent quarks in a rigorous manner, given physical assumptions that hold in the large-N-c, limit of QCD. This constituent picture gives rise to an operator expansion that has been used to study largeN(c), baryon observables; here we apply it to the case of charge radii of the N and Delta states, using minimal dynamical assumptions. For example, one finds the relation r(p)(2) - r(Delta+)(2) = r(n)(2) - r(Delta0)(2) to be broken only by three-body, O(1/N-c(2)) effects for any N-c. C1 Univ Tubingen, Inst Theoret Phys, D-72076 Tubingen, Germany. Jefferson Lab, Newport News, VA 23606 USA. RP Buchmann, AJ (reprint author), Univ Tubingen, Inst Theoret Phys, D-72076 Tubingen, Germany. EM alfons.buchmann@uni-tuebingen.de; iebed@jlab.org NR 28 TC 42 Z9 42 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 NOV 1 PY 2000 VL 62 IS 9 AR 096005 DI 10.1103/PhysRevD.62.096005 PG 7 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 370EW UT WOS:000165111400099 ER PT J AU Carena, M Choudhury, D Quigg, C Raychaudhuri, S AF Carena, M Choudhury, D Quigg, C Raychaudhuri, S TI Study of R-parity violation at a mu p collider SO PHYSICAL REVIEW D LA English DT Article ID DEEP-INELASTIC SCATTERING; NEUTRINO PHYSICS; LEPTON NUMBER; SUPERSYMMETRIC THEORIES; CONTACT INTERACTIONS; STANDARD MODEL; BREAKING; SYMMETRIES; COUPLINGS; HERA AB To explore the discovery possibilities of a high-energy muon-proton collider, we examine signals that could arise from direct-channel formation of supersymmetric-particle resonances through operators that do not respect R parity. C1 Fermilab Natl Accelerator Lab, Dept Theoret Phys, Batavia, IL 60510 USA. Mehta Res Inst, Allahabad 211019, Uttar Pradesh, India. Indian Inst Technol, Dept Phys, Kanpur 208016, Uttar Pradesh, India. RP Fermilab Natl Accelerator Lab, Dept Theoret Phys, POB 500, Batavia, IL 60510 USA. EM carena@fnal.gov; debchou@mri.ernet.in; quigg@fnal.gov; sreerup@iitk.ac.in NR 63 TC 3 Z9 3 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0010 EI 2470-0029 J9 PHYS REV D JI Phys. Rev. D PD NOV 1 PY 2000 VL 62 IS 9 AR 095010 DI 10.1103/PhysRevD.62.095010 PG 10 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 370EW UT WOS:000165111400090 ER PT J AU Gardner, S Valencia, G AF Gardner, S Valencia, G TI Impact of vertical bar Delta I vertical bar=5/2 transitions in K ->pi pi decays SO PHYSICAL REVIEW D LA English DT Article ID CHIRAL PERTURBATION-THEORY; DIRECT CP VIOLATION; PI-PI-SCATTERING; VIRTUAL PHOTONS; NEUTRAL KAON; EPSILON'/EPSILON; RULE; EXPANSION; PARAMETER; PHYSICS AB We consider the impact of isospin violation on the analysis of K-->pi pi decays. We scrutinize, in particular, the phenomenological role played by the additional weak amplitude, of \DeltaI\ = 5/2 in character, incurred by the presence of isospin violation. We show that Watson's theorem is appropriate in O(m(d)-m(u)), so that the inferred pi pi phase shift at roots=m(K) determines the strong phase difference between the I=0 and I=2 amplitudes in K-->pi pi decay. We find the magnitude of the \DeltaI\=5/2 amplitude thus implied by the empirical branching ratios to be larger than expected from estimates of isospin-violating strong and electromagnetic effects. We effect a new determination of the octet and 27-plet coupling constants with strong-interaction isospin violation and with electromagnetic effects, as computed by Cirigliano, Donoghue, and Golowich, and find that we are unable to resolve the difficulty. Exploring the role of \DeltaI\ = 5/2 transitions in the CP violating observable epsilon'/epsilon, We determine that the presence of a \DeltaI\ = 5/2 amplitude impacts the empirical determination of omega, the ratio of the real parts of the \DeltaI\ = 3/2 to \DeltaI\ = 1/2 amplitudes, and that it generates a decrease in the estimation of epsilon'/epsilon. C1 Univ Kentucky, Dept Phys & Astron, Lexington, KY 40506 USA. Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. RP Gardner, S (reprint author), Univ Kentucky, Dept Phys & Astron, Lexington, KY 40506 USA. EM gardner@pa.uky.edu; valencia@iastate.edu NR 45 TC 17 Z9 17 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 NOV 1 PY 2000 VL 62 IS 9 AR 094024 DI 10.1103/PhysRevD.62.094024 PG 15 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 370EW UT WOS:000165111400062 ER PT J AU Lebed, RF Uraltsev, NG AF Lebed, RF Uraltsev, NG TI Precision studies of duality in the 't Hooft model SO PHYSICAL REVIEW D LA English DT Article ID QUARK-HADRON DUALITY; MESON WEAK DECAYS; HEAVY QUARKS; SUM-RULES; EXPANSION; DISTRIBUTIONS; MASS AB We address the numerical aspects of local quark-hadron duality using the example of the exactly solvable 't Hooft model, two-dimensional QCD with N-c-->infinity. The primary focus of these studies is the total semileptonic decay widths relevant for extracting \V-cb\ and \V-ub\. We compare the exact channel-by-channel sum of exclusive modes to the corresponding rates obtained in the standard 1/m(Q) expansion arising from the operator product expansion. An impressive agreement sets in unexpectedly early, immediately after the threshold for the first hadronic excitation in the final state. Yet even at higher energy release it is possible to discern the seeds of duality-violating oscillations. We find the "small velocity" sum rules to be exceptionally well saturated already by the first excited state. We also obtain a convincing degree of duality in the differential distributions and in an analogue of Re+e-(s). Finally, we discuss possible lessons for semileptonic decays of actual heavy quarks in QCD. C1 Jefferson Lab, Newport News, VA 23606 USA. Univ Notre Dame, Dept Phys, Notre Dame, IN 46556 USA. Petersburg Nucl Phys Inst, St Petersburg 188350, Russia. RP Jefferson Lab, 12000 Jefferson Ave, Newport News, VA 23606 USA. EM lebed@jlab.org; uraltsev@undhep.hep.nd.edu NR 34 TC 26 Z9 26 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 NOV 1 PY 2000 VL 62 IS 9 AR 094011 DI 10.1103/PhysRevD.62.094011 PG 21 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 370EW UT WOS:000165111400049 ER PT J AU Martin, SP AF Martin, SP TI Collider signals from slow decays in supersymmetric models with an intermediate-scale solution to the mu problem SO PHYSICAL REVIEW D LA English DT Article ID STRONG CP-PROBLEM; FERMILAB TEVATRON; BREAKING MODELS; STANDARD MODEL; LIGHTEST NEUTRALINO; HARMLESS AXION; HIGGS BOSONS; DARK MATTER; AXINO MASS; CERN LHC AB The problem of the origin of the mu parameter in the minimal supersymmetric standard model can be solved by introducing singlet supermultiplets with non-renormalizable couplings to the ordinary Higgs supermultiplets. The Peccei-Quinn symmetry is broken at a scale which is the geometric mean between the weak scale and the Planck scale, yielding a mu term of the right order of magnitude and an invisible axion. These models also predict one or more singlet fermions which have electroweak-scale masses and suppressed couplings to MSSM states. I consider the case that such a singlet fermion, containing the axino as an admixture, is the lightest supersymmetric particle. I work out the relevant couplings in several of the simplest models of this type, and compute the partial decay widths of the next-to-lightest supersymmetric particle involving leptons or jets. Although these decays will have an average proper decay length which is most likely much larger than a typical collider detector, they can occasionally occur within the detector, providing a striking signal. With a large sample of supersymmetric events, there will be an opportunity to observe these decays, and so gain direct information about physics at very high energy scales. C1 No Illinois Univ, Dept Phys, De Kalb, IL 60115 USA. Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. RP Martin, SP (reprint author), No Illinois Univ, Dept Phys, De Kalb, IL 60115 USA. NR 52 TC 26 Z9 26 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD NOV 1 PY 2000 VL 62 IS 9 AR 095008 DI 10.1103/PhysRevD.62.095008 PG 12 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 370EW UT WOS:000165111400088 ER PT J AU Melnikov, K Weinstein, M AF Melnikov, K Weinstein, M TI Lattice Schwinger model: Confinement, anomalies, chiral fermions, and all that SO PHYSICAL REVIEW D LA English DT Article AB In order to better understand what to expect from numerical CORE computations for two-dimensional massless QED (the Schwinger model) we wish to obtain some analytic control over the approach to the continuum limit for various choices of fermion derivative. To this end we study the Hamiltonian formulation of the lattice Schwinger model (i.e., the theory defined on the spatial lattice with continuous time) in A(o)=0 gauge. We begin with a discussion of the solution of the Hamilton equations of motion in the continuum; we then parallel the derivation df the continuum solution within the lattice framework for a range of fermion derivatives. The equations of motion for the Fourier transform of the lattice charge density operator show explicitly why it is a regulated version of this operator which corresponds to the point-split operator of the continuum theory and the sense in which the regulated lattice operator can be treated as a Bose field. The same formulas explicitly exhibit operators whose matrix elements measure the lack of approach to the continuum physics. We show that both chirality violating Wilson-type and chirality preserving SLAC-type derivatives correctly reproduce the continuum theory and show that there is a clear connection between the strong and weak coupling limits of a theory based upon a generalized SLAC-type derivative. C1 Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Melnikov, K (reprint author), Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. EM melnikov@slac.stanford.edu; niv@slac.stanford.edu NR 17 TC 1 Z9 1 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 NOV 1 PY 2000 VL 62 IS 9 AR 094504 PG 14 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 370EW UT WOS:000165111400073 ER PT J AU Schafer, T AF Schafer, T TI Quark hadron continuity in QCD with one flavor SO PHYSICAL REVIEW D LA English DT Article ID FINITE BARYON DENSITY; COLOR SUPERCONDUCTIVITY; MATTER AB We study QCD with one flavor at finite baryon density. In the limit of very high baryon density the system is expected to be a color superconductor. In the case of one flavor, the order parameter is in a (3) over bar of color and has a total angular momentum of 1. We show that, in weak coupling perturbation theory, the energetically preferred phase exhibits "color-spin locking"; i.e., the color and spin direction of the condensate are aligned. We discuss the properties of this phase and argue that it shares important features of the hadronic phase at low density. In particular, we find an unbroken rotational symmetry, spin-3/2 quasiparticles, and an unusual mechanism for quark-antiquark condensation. Our results are relevant to three flavor QCD in the regime where the strange quark mass is bigger than the critical value for color-flavor locking. We find that the gaps in this case are on the order of 1 MeV. C1 SUNY Stony Brook, Dept Phys, Stony Brook, NY 11794 USA. Brookhaven Natl Lab, Res Ctr, RIKEN, Upton, NY 11973 USA. RP SUNY Stony Brook, Dept Phys, Stony Brook, NY 11794 USA. NR 33 TC 138 Z9 140 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0010 EI 2470-0029 J9 PHYS REV D JI Phys. Rev. D PD NOV 1 PY 2000 VL 62 IS 9 AR 094007 DI 10.1103/PhysRevD.62.094007 PG 10 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 370EW UT WOS:000165111400045 ER PT J AU Schmaltz, M Skiba, W AF Schmaltz, M Skiba, W TI Minimal gaugino mediation SO PHYSICAL REVIEW D LA English DT Article ID SUPERSYMMETRIC STANDARD MODEL; RENORMALIZATION-GROUP; LEPTON-FLAVOR; BREAKING; SUPERGRAVITY; EXTENSIONS; COUPLINGS; PARTICLE; CP AB We propose minimal gaugino mediation as the simplest known solution to the supersymmetric flavor and CP problems. The framework predicts a very minimal structure for the soft parameters at ultrahigh energies: gaugino masses are unified and non-vanishing whereas all other soft supersymmetry breaking parameters vanish. We show that this boundary condition naturally arises from a small extra dimension and present a complete model which includes a new extra-dimensional solution to the CL problem. We briefly discuss the predicted superpartner spectrum as a function of the two parameters of the model. The commonly ignored renormalization group evolution above the GUT scale is crucial to the viability of minimal gaugino mediation but does not introduce new model dependence. C1 Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. Univ Calif San Diego, Dept Phys, La Jolla, CA 92093 USA. RP Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. EM schmaltz@slac.stanford.edu; skiba@einstein.ucsd.edu NR 28 TC 102 Z9 102 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 NOV 1 PY 2000 VL 62 IS 9 AR 095005 DI 10.1103/PhysRevD.62.095005 PG 8 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 370EW UT WOS:000165111400085 ER PT J AU Schmaltz, M Skiba, W AF Schmaltz, M Skiba, W TI Superpartner spectrum of gaugino mediation SO PHYSICAL REVIEW D LA English DT Article ID DYNAMICAL SUPERSYMMETRY BREAKING; FERMILAB TEVATRON; UNIFIED THEORIES; ANOMALOUS U(1); STANDARD MODEL; SUPERGRAVITY; SCALE; TRILEPTON; TERMS; UNIFICATION AB We compute the superpartner masses in a class of models with gaugino mediation (or no-scale) boundary conditions at a scale between the GUT and Planck scales. These models are compelling because they are simple, solve the supersymmetric flavor and CP problems, satisfy all constraints from colliders and cosmology, and predict the superpartner masses in terms of very few parameters. Our analysis includes the renormalization group evolution of the soft-breaking terms above the GUT scale. We show that the running above the GUT scale is largely model independent and find that a phenomenologically viable spectrum is obtained. C1 Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. Univ Calif San Diego, Dept Phys, La Jolla, CA 92093 USA. RP Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. EM schmaltz@slac.stanford.edu; skiba@einstein.ucsd.edu NR 39 TC 72 Z9 72 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 NOV 1 PY 2000 VL 62 IS 9 AR 095004 DI 10.1103/PhysRevD.62.095004 PG 7 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 370EW UT WOS:000165111400084 ER PT J AU Stephenson, GJ Goldman, T McKellar, BHJ AF Stephenson, GJ Goldman, T McKellar, BHJ TI Tritium beta decay, neutrino mass matrices, and interactions beyond the standard model SO PHYSICAL REVIEW D LA English DT Article ID FINAL-STATE INTERACTIONS; ANTINEUTRINO REST MASS; LEFT-RIGHT SYMMETRY; CP-VIOLATION; (NU)OVER-BAR(MU)->(NU)OVER-BAR(E) OSCILLATIONS; MOLECULAR TRITIUM; LSND EXPERIMENT; LEPTON NUMBER; UPPER LIMIT; MUON DECAY AB The interference of charge changing interactions, weaker than the V-A standard model (SM) interaction and having a different Lorentz structure, with that SM interaction, can, in principle, produce effects near the end point of the tritium beta decay spectrum which are of a different character from those produced by the purely kinematic effect of neutrino mass expected in the simplest extension of the SM. We show that the existence of more than one mass eigenstate can lead to interference effects at the end point that are stronger than those occurring over the entire spectrum. We discuss these effects both for the special case of Dirac neutrinos and the more general case of Majorana neutrinos and show that, for the present precision of the experiments, one formula should suffice to express the interference effects in all cases. Implications for "sterile" neutrinos are noted. C1 Univ New Mexico, Albuquerque, NM 87131 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Melbourne, Parkville, Vic 3052, Australia. RP Stephenson, GJ (reprint author), Univ New Mexico, Albuquerque, NM 87131 USA. EM gjs@baryon.phys.unm.edu; goldman@t5.lanl.gov; b.mckellar@physics.unimelb.edu.au NR 67 TC 13 Z9 13 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 NOV 1 PY 2000 VL 62 IS 9 AR 093013 DI 10.1103/PhysRevD.62.093013 PG 13 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 370EW UT WOS:000165111400024 ER PT J AU Suzuki, M AF Suzuki, M TI Selection rules in three-body B decay from factorization SO PHYSICAL REVIEW D LA English DT Article ID HEAVY MESON DECAYS; PHASES AB Extending the dynamics underlying the factorization calculation of two-body decays, we propose simple selection rules for nonresonant three-body B decays. We predict, for instance, that in the Dalitz plot of B-0 -->(D) over bar (0)pi (+)pi (-), practically no events should be found in the corner region of E(pi (+))less than or equal to Lambda (QCD) as compared with the corner of E(pi (-))less than or equal to Lambda (QCD). We also predict that there should be very few three-body decay events containing one soft meson resonance and two energetic mesons or meson resonances. The selection rules are quite different from the soft-pion theorem, since they apply to different kinematical regions. For B-0-->(D) over bar (0)pi (+)pi (-), the latter predicts that the decay matrix element vanishes in the zero four-momentum limit of pi (-) instead of pi (+) Since this marked difference from the soft-pion theorem is directly related to the issue of short-distance QCD dominance in two-body B decays, experimental tests of the selection rules will shed light on the strong interaction dynamics of B decay. C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Suzuki, M (reprint author), Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. NR 24 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 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD NOV 1 PY 2000 VL 62 IS 9 AR 091502 PG 5 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 370EW UT WOS:000165111400004 ER PT J AU Szczepaniak, AP Swanson, ES AF Szczepaniak, AP Swanson, ES TI Nonperturbative renormalization and the QCD vacuum SO PHYSICAL REVIEW D LA English DT Article ID CHIRAL-SYMMETRY-BREAKING; EQUATIONS; HAMILTONIANS; QUARKS AB We present a self-consistent approach to Coulomb gauge Hamiltonian QCD which allows one to relate single gluon spectral properties to the long range behavior of the confining interaction. Nonperturbative renormalization is discussed. The numerical results are in good agreement with phenomenological and lattice forms of the static potential. C1 Indiana Univ, Dept Phys, Bloomington, IN 47405 USA. Indiana Univ, Ctr Nucl Theory, Bloomington, IN 47405 USA. Univ Pittsburgh, Dept Phys & Astron, Pittsburgh, PA 15260 USA. Jefferson Lab, Newport News, VA 23606 USA. RP Szczepaniak, AP (reprint author), Indiana Univ, Dept Phys, Bloomington, IN 47405 USA. NR 29 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 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD NOV 1 PY 2000 VL 62 IS 9 AR 094027 DI 10.1103/PhysRevD.62.094027 PG 9 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 370EW UT WOS:000165111400065 ER PT J AU Wall, D Allison, WWM Alner, GJ Ayres, DS Barrett, WL Bode, C Border, PM Cobb, JH Cotton, R Courant, H Chung, J Demuth, DM Fields, TH Gallagher, HR Goodman, MC Gran, R Joffe-Minor, T Kafka, T Kasahara, SMS Leeson, W Litchfield, PJ Mann, WA Marshak, ML Milburn, RH Miller, WH Mualem, L Napier, A Oliver, WP Pearce, GF Peterson, EA Petyt, DA Price, LE Ruddick, K Sanchez, M Schneps, J Stassinakis, A Thron, JL Wakely, SP West, N AF Wall, D Allison, WWM Alner, GJ Ayres, DS Barrett, WL Bode, C Border, PM Cobb, JH Cotton, R Courant, H Chung, J Demuth, DM Fields, TH Gallagher, HR Goodman, MC Gran, R Joffe-Minor, T Kafka, T Kasahara, SMS Leeson, W Litchfield, PJ Mann, WA Marshak, ML Milburn, RH Miller, WH Mualem, L Napier, A Oliver, WP Pearce, GF Peterson, EA Petyt, DA Price, LE Ruddick, K Sanchez, M Schneps, J Stassinakis, A Thron, JL Wakely, SP West, N TI Search for nucleon decay with final states l(+) eta(0), (nu)over-bar eta(0), and (nu)over-bar pi(+,0) using Soudan 2 SO PHYSICAL REVIEW D LA English DT Article ID TRACKING CALORIMETER MODULES; PROTON DECAY; ATMOSPHERIC NEUTRINOS; EXPERIMENTAL LIMITS; FREJUS EXPERIMENT; MODES; DETECTOR; FLUX; LIFETIME; SO(10) AB We have searched for nucleon decay into five two-body final states using a 4.4 kiloton-year fiducial exposure of the Soudan 2 iron tracking calorimeter. For proton decay into the fully visible final states mu (+) eta (0) and e(+) eta (0), we observe zero and one event, respectively, that satisfy our search criteria for nucleon decay. The lifetime lower limits (tau /B) thus implied are 89 x 10(30) years and 81 x 10(30) years at 90% confidence level. For neutron decay into <()over bar>eta0, we obtain the lifetime lower limit 71 x 10(30) years. Limits are also reported for neutron decay into <()over bar>pi (0), and for proton decay into <()over bar>pi (+). C1 Argonne Natl Lab, Argonne, IL 60439 USA. Univ Minnesota, Minneapolis, MN 55455 USA. Univ Oxford, Dept Phys, Oxford OX1 3RH, England. Rutherford Appleton Lab, Didcot OX11 0QX, Oxon, England. Tufts Univ, Medford, MA 02155 USA. Western Washington Univ, Bellingham, WA 98225 USA. RP Wall, D (reprint author), Sapient Corp, 1 Mem Dr, Cambridge, MA 02142 USA. RI Cotton, Richard/K-2175-2012 NR 46 TC 9 Z9 9 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD NOV 1 PY 2000 VL 62 IS 9 AR 092003 DI 10.1103/PhysRevD.62.092003 PG 11 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 370EW UT WOS:000165111400007 ER PT J AU Dellago, C Hoover, WG AF Dellago, C Hoover, WG TI Finite-precision stationary states at and away from equilibrium SO PHYSICAL REVIEW E LA English DT Article ID CORRELATION DIMENSION; LORENTZ GAS; MAPS AB We study the precision dependence of equilibrium and nonequilibrium phase-space distribution functions for time-reversible dynamical systems simulated with finite, computational precision. The conservative and dissipative cases show different behavior, with substantially reduced period lengths in the dissipative case. The main effect of finite precision is to change the phase-space fraction occupied by the distributions. The convergence of thermodynamic averages is only slightly affected. We introduce and discuss a simple stochastic model which is nicely consistent with all of our numerical results. This model links the length of periodic orbits to the strange attractor's correlation dimension. C1 Univ Rochester, Dept Chem, Rochester, NY 14627 USA. Univ Calif Davis, Dept Appl Sci, Livermore, CA 94551 USA. Univ Calif Lawrence Livermore Natl Lab, Dept Mech Engn, Methods Dev Grp, Livermore, CA 94551 USA. RP Dellago, C (reprint author), Univ Rochester, Dept Chem, Rochester, NY 14627 USA. RI Dellago, Christoph/E-1625-2011 NR 14 TC 12 Z9 13 U1 0 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 NOV PY 2000 VL 62 IS 5 BP 6275 EP 6281 DI 10.1103/PhysRevE.62.6275 PN A PG 7 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 374JH UT WOS:000165341700057 ER PT J AU Resat, H Mezei, M AF Resat, H Mezei, M TI Calculating the local solvent chemical potential in crystal hydrates SO PHYSICAL REVIEW E LA English DT Article ID ENSEMBLE MONTE-CARLO; MOLECULAR-DYNAMICS; FREE-ENERGY; CYTOCHROME P450CAM; LENNARD-JONES; WATER; SIMULATION; THERMODYNAMICS AB Determining solvation patterns in biological systems is crucial in investigating the functional role water may play in structural stabilization and molecular recognition. Determining whether a particular position would be occupied by a solvent molecule requires the local thermodynamics to be known. In this work we introduce a simple and inexpensive approach based on grand canonical molecular simulations to determine the occupancy factors of the cavities. The method is applied to the test case of the sodium salt of hyaluronic acid. The results agree very well with experimental results and demonstrate the success of the method. C1 Koc Univ, Coll Arts & Sci, Istanbul, Turkey. NYU, Mt Sinai Sch Med, Dept Phys & Biophys, New York, NY 10029 USA. RP Resat, H (reprint author), Pacific NW Natl Lab, POB 999,Mail Stop K1-83, Richland, WA 99352 USA. NR 21 TC 1 Z9 2 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 NOV PY 2000 VL 62 IS 5 BP 7077 EP 7081 DI 10.1103/PhysRevE.62.7077 PN B PG 5 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 374JK UT WOS:000165341900046 PM 11102064 ER PT J AU Marconi, MC Moreno, CH Rocca, JJ Shlyaptsev, VN Osterheld, AL AF Marconi, MC Moreno, CH Rocca, JJ Shlyaptsev, VN Osterheld, AL TI Dynamics of a microcapillary discharge plasma using a soft x-ray laser backlighter SO PHYSICAL REVIEW E LA English DT Article ID CAPILLARY-DISCHARGE; WAVE-GUIDE; ELECTRON-DENSITY; REPETITION RATE; TRANSIENT GAIN; PULSES; AMPLIFICATION; EXCITATION; AMPLIFIER; EMISSION AB We have used the new technique of soft x-ray laser shadowgraphy in combination with traditional plasma emission spectroscopy and theoretical modeling to study the dynamics of a plasma column created by a discharge through a 380 mum diameter evacuated microcapillary. The transient microcapillary plasma was imaged with high-spatial and temporal resolution using a tabletop discharge pumped 46.9-nm laser backlighter. Model computations show that the sharp boundary observed between the absorbent and transparent regions of the shadowgrams is defined by the spatial distribution of weakly ionized ions that are strongly photoionized by the probe: laser. The plasma was observed to rapidly evolve from an initially nonuniform distribution into a column with good azimuthal symmetry and minimum density on axis [computed electron density on axis n(e) = (1-3) X 10(19) cm(-3)]. This concave electron density profile constitutes a plasma waveguide for laser radiation. Heated solely by Joule dissipation from relatively small excitation currents (1.5 kA), this dense plasma reaches substantial electron temperatures of T-e = 15-20 eV as a result of the absence of significant hydrodynamic losses and reduced radiation losses caused by large spectral line opacities. The results illustrate the potential of tabletop soft x-ray lasers as a new plasma diagnostic tool. C1 Colorado State Univ, Dept Elect & Comp Engn, Ft Collins, CO 80523 USA. Univ Calif Davis, Dept Appl Sci, Livermore, CA 94551 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Univ Buenos Aires, Dept Fis, FCEyN, Buenos Aires, DF, Argentina. RP Marconi, MC (reprint author), Colorado State Univ, Dept Elect & Comp Engn, Ft Collins, CO 80523 USA. NR 57 TC 32 Z9 32 U1 1 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 NOV PY 2000 VL 62 IS 5 BP 7209 EP 7218 DI 10.1103/PhysRevE.62.7209 PN B PG 10 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 374JK UT WOS:000165341900059 ER PT J AU Zhidkov, A Sasaki, A Utsumi, T Fukumoto, I Tajima, T Saito, F Hironaka, Y Nakamura, KG Kondo, K Yoshida, M AF Zhidkov, A Sasaki, A Utsumi, T Fukumoto, I Tajima, T Saito, F Hironaka, Y Nakamura, KG Kondo, K Yoshida, M TI Prepulse effects on the interaction of intense femtosecond laser pulses with high-Z solids SO PHYSICAL REVIEW E LA English DT Article ID ABSORPTION; GENERATION; PLASMAS; TARGET; CODE AB K alpha emission of high-Z solid targets irradiated by an intense, short (<100 fs) laser pulse in the 10 keV region is shown to be sensitive to the electron energy cutoff, which is strongly dependent on the density,gradient of the plasma corona formed by a long prepulse. The absorption rate of short laser pulses, the hot electron distribution, and x-ray emission from a Cu slab target are studied via a hybrid model, which combines the hydrodynamics, collisional particle-in-cell, and Monte Carlo simulation techniques, and via a direct spectroscopic measurement. An absorption mechanism originating from the interaction of the laser pulse with plasma waves is found to increase the absorption rate by over 30% even for a very short, s-polarized laser pulse. Calculated and measured x-ray spectra are in good agreement, confirming the electron energy cutoff. C1 JAERI, Adv Photon Res Ctr, Neyagawa, Osaka 5720019, Japan. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Tokyo Inst Technol, Mat & Struct Lab, Midori Ku, Yokohama, Kanagawa 2268503, Japan. Natl Inst Mat & Chem Res, Tsukuba, Ibaraki 3058565, Japan. RP Zhidkov, A (reprint author), JAERI, Adv Photon Res Ctr, 25-1 Mii Minami Machi, Neyagawa, Osaka 5720019, Japan. RI Nakamura, Kazutaka/F-4095-2014; Sasaki, Akira/J-8158-2016 NR 24 TC 46 Z9 55 U1 0 U2 12 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1063-651X J9 PHYS REV E JI Phys. Rev. E PD NOV PY 2000 VL 62 IS 5 BP 7232 EP 7240 DI 10.1103/PhysRevE.62.7232 PN B PG 9 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 374JK UT WOS:000165341900062 ER PT J AU Huang, ZR Kim, KJ AF Huang, ZR Kim, KJ TI Three-dimensional analysis of harmonic generation in high-gain free-electron lasers SO PHYSICAL REVIEW E LA English DT Article ID AMPLIFIED SPONTANEOUS EMISSION; RADIATION; WIGGLERS AB In a high-gain free-electron laser (FEL) employing a planar undulator, strong bunching at the fundamental wavelength can drive substantial bunching and power levels at the harmonic frequencies. In this paper we investigate the three-dimensional evolution of harmonic radiation based on the coupled Maxwell-Klimoniovich equations that take into account nonlinear harmonic interactions. Each harmonic field is a sum of a linear amplification term and a term driven by nonlinear harmonic interactions. After a certain stage of exponential growth, the dominant nonlinear term is determined by interactions of the lower nonlinear harmonics and the fundamental radiation. As a result, the gain length, transverse profile, and temporal structure of the first few harmonics are eventually governed by those of the fundamental. Transversely coherent third-harmonic radiation power is found to approach 1% of the fundamental power level for current high-gain FEL projects. C1 Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. RP Huang, ZR (reprint author), Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. NR 36 TC 85 Z9 86 U1 1 U2 10 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1063-651X J9 PHYS REV E JI Phys. Rev. E PD NOV PY 2000 VL 62 IS 5 BP 7295 EP 7308 DI 10.1103/PhysRevE.62.7295 PN B PG 14 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 374JK UT WOS:000165341900071 ER PT J AU Vanossi, A Rasmussen, KO Bishop, AR Malomed, BA Bortolani, V AF Vanossi, A Rasmussen, KO Bishop, AR Malomed, BA Bortolani, V TI Spontaneous pattern formation in driven nonlinear lattices SO PHYSICAL REVIEW E LA English DT Article ID OSCILLATED GRANULAR LAYERS; MODES AB We demonstrate the spontaneous formation of spatial patterns in a damped, ac-driven cubic Klein-Gordon lattice. These patterns are composed of arrays of intrinsic localized modes characteristic for nonlinear lattices. We analyze the modulation instability leading to this spontaneous pattern formation. Our calculation of the modulational instability is applicable in one- and two-dimensional lattices; however, in the analyses of the emerging patterns we concentrate particularly on the two-dimensional case. C1 Los Alamos Natl Lab, Ctr Nonlinear Studies, Los Alamos, NM 87545 USA. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Univ Bologna, Dipartmento Fis, I-40127 Bologna, Italy. Univ Modena, Dipartimento Fis, I-41100 Modena, Italy. Univ Modena, INFM, I-41100 Modena, Italy. Fac Engn, Dept Interdisciplinary Studies, IL-69975 Tel Aviv, Israel. RP Los Alamos Natl Lab, Ctr Nonlinear Studies, POB 1663, Los Alamos, NM 87545 USA. RI Rasmussen, Kim/B-5464-2009 OI Rasmussen, Kim/0000-0002-4029-4723 NR 15 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 2470-0045 EI 2470-0053 J9 PHYS REV E JI Phys. Rev. E PD NOV PY 2000 VL 62 IS 5 BP 7353 EP 7357 DI 10.1103/PhysRevE.62.7353 PN B PG 5 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 374JK UT WOS:000165341900078 ER PT J AU Qiang, J Habib, S AF Qiang, J Habib, S TI Second-order stochastic leapfrog algorithm for multiplicative noise Brownian motion SO PHYSICAL REVIEW E LA English DT Article ID OSCILLATOR; SIMULATION; COSMOLOGY; SYSTEMS AB A stochastic leapfrog algorithm For the numerical integration of Brownian motion stochastic differential equations with multiplicative noise is proposed and tested. The algorithm has a second-order convergence of moments in a finite time interval and requires the sampling of only one uniformly distributed random variable per time step. The noise may be white or colored. We apply the algorithm to a study of the approach towards equilibrium of an oscillator coupled nonlinearly to a heat bath and investigate the effect of the multiplicative noise (arising from the nonlinear coupling) on the relaxation time. This allows us to test the regime of validity of the energy-envelope approximation method. C1 Univ Calif Los Alamos Natl Lab, LANSCE 1, MS H817, Los Alamos, NM 87545 USA. Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Qiang, J (reprint author), Univ Calif Los Alamos Natl Lab, LANSCE 1, MS H817, POB 1663, Los Alamos, NM 87545 USA. NR 24 TC 14 Z9 14 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 NOV PY 2000 VL 62 IS 5 BP 7430 EP 7437 DI 10.1103/PhysRevE.62.7430 PN B PG 8 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 374JK UT WOS:000165341900087 ER PT J AU Stout, EC Beck, CW Anderson, KB AF Stout, EC Beck, CW Anderson, KB TI Identification of rumanite (Romanian amber) as thermally altered succinite (Baltic amber) SO PHYSICS AND CHEMISTRY OF MINERALS LA English DT Article DE amber; rumantite; succinite; pyrolysis; gas chromatography; mass spectrometry ID NATURAL RESINS; GEOSPHERE; FATE AB Romanian amber (rumanite) has been considered to be a separate species of fossil resin for more than a century. While earlier investigators held it to be very similar to succinite (Baltic amber), modern scholars have assigned it a distinctly different botanical origin. We have found that almost all of the constituents of the ether-soluble fractions of 13 specimens of authentic rumanite identified by gas chromatography-mass spectrometry have previously been reported in the soluble fraction of succinite, including succinic acid and its monoterpene esters. Additionally and significantly, the soluble fraction of rumanite contains a number defunctionalized compounds that do not preexist in succinite, but that are produced by pyrolysis of whole succinite or of its insoluble polymeric fraction. Simultaneous methylation pyrolysis-gas chromatography-mass spectrometry of the polymeric fraction of seven of the rumanite specimens yielded further copious amounts of dimethyl succinate, a number of diterpene resin acid methyl esters, and additional defunctionalized compounds known to be pyrolysis products of succinite. The evidence shows conclusively that the botanical origin of rumanite is not distinct from that of succinite. Rather, rumanite is a succinite that has suffered partial thermal degradation in the course of the folding of the Oligocene Kliwa sandstone formation in which it is most commonly found. C1 Vassar Coll, Dept Chem, Amber Res Lab, New York, NY 12604 USA. Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. RP Beck, CW (reprint author), Vassar Coll, Dept Chem, Amber Res Lab, Box 0092,124 Raymond Ave Poughkeepsie, New York, NY 12604 USA. NR 61 TC 25 Z9 26 U1 0 U2 5 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0342-1791 J9 PHYS CHEM MINER JI Phys. Chem. Miner. PD NOV PY 2000 VL 27 IS 9 BP 665 EP 678 DI 10.1007/s002690000111 PG 14 WC Materials Science, Multidisciplinary; Mineralogy SC Materials Science; Mineralogy GA 376NJ UT WOS:000165463400011 ER PT J AU Maltz, JS AF Maltz, JS TI Direct recovery of regional tracer kinetics from temporally inconsistent dynamic ECT projections using dimension-reduced time-activity basis SO PHYSICS IN MEDICINE AND BIOLOGY LA English DT Article ID SPECT; MODEL; TOMOGRAPHY; PARAMETERS; ALGORITHM; PET AB We present an algorithm of reduced computational cost which is able to estimate kinetic model parameters directly from dynamic ECT sinograms made up of temporally inconsistent projections. The algorithm exploits the extreme degree of parameter redundancy inherent in linear combinations of the exponential functions which represent the modes of first-order compartmental systems. The singular value decomposition is employed to find a small set of orthogonal functions, the linear combinations of which are able to accurately represent all modes within the physiologically anticipated range in a given study. The reduced-dimension basis is formed as the convolution of this orthogonal set with a measured input function. The Moore-Penrose pseudoinverse is used to find coefficients of this basis. Algorithm performance is evaluated at realistic count rates using MCAT phantom and clinical Tc-99m-teboroxime myocardial study data. Phantom data are modelled as originating from a Poisson process. For estimates recovered from a single slice projection set containing 2.5 x 10(5) total counts, recovered tissue responses compare favourably with those obtained using more computationally intensive methods. The corresponding kinetic parameter estimates (coefficients of the new basis) exhibit negligible bias, while parameter variances are low, falling within 30% of the Cramer-Rao lower bound. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Funct Imaging, Berkeley, CA 94720 USA. RP Maltz, JS (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Funct Imaging, Berkeley, CA 94720 USA. FU NHLBI NIH HHS [HL-07367, R01-HL50663, P01-HL25840] NR 17 TC 10 Z9 10 U1 0 U2 3 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0031-9155 J9 PHYS MED BIOL JI Phys. Med. Biol. PD NOV PY 2000 VL 45 IS 11 BP 3413 EP 3429 DI 10.1088/0031-9155/45/11/322 PG 17 WC Engineering, Biomedical; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Radiology, Nuclear Medicine & Medical Imaging GA 374KD UT WOS:000165343600022 PM 11098914 ER PT J AU Noo, F Clackdoyle, R Mennessier, C White, TA Roney, TJ AF Noo, F Clackdoyle, R Mennessier, C White, TA Roney, TJ TI Analytic method based on identification of ellipse parameters for scanner calibration in cone-beam tomography SO PHYSICS IN MEDICINE AND BIOLOGY LA English DT Article ID EMISSION COMPUTED-TOMOGRAPHY; DISPLACED CENTER; GEOMETRICAL PARAMETERS; FAN-BEAM; SPECT; ROTATION; SYSTEM; RECONSTRUCTION; ALGORITHM AB This paper is about calibration of cone-beam (CB) scanners for both x-ray computed tomography and single-photon emission computed tomography. Scanner calibration refers here to the estimation of a set of parameters which fully describe the geometry of data acquisition. Such parameters are needed for the tomographic reconstruction step. The discussion is limited to the usual case where the cone vertex and planar detector move along a circular path relative to the object. It is also assumed that the detector does not have spatial distortions. We propose a new method which requires a small set of measurements of a simple calibration object consisting of two spherical objects, that can be considered as 'point' objects. This object traces two ellipses on the detector and from the parametric description of these ellipses, the calibration geometry can be determined analytically using explicit formulae. The method is robust and easy to implement. However, it is not fully general as it is assumed that the detector is parallel to the rotation axis of the scanner. Implementation details are given for an experimental x-ray CB scanner. C1 Univ Liege, Inst Elect Montefiore, B-4000 Liege, Belgium. Univ Utah, Dept Radiol, Salt Lake City, UT 84112 USA. Univ Grenoble 1, Grenoble, France. Idaho Natl Engn & Environm Lab, Idaho Falls, ID USA. RP Noo, F (reprint author), Univ Liege, Motefiore Inst, B28, B-4000 Liege, Belgium. NR 20 TC 129 Z9 145 U1 0 U2 14 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0031-9155 J9 PHYS MED BIOL JI Phys. Med. Biol. PD NOV PY 2000 VL 45 IS 11 BP 3489 EP 3508 DI 10.1088/0031-9155/45/11/327 PG 20 WC Engineering, Biomedical; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Radiology, Nuclear Medicine & Medical Imaging GA 374KD UT WOS:000165343600027 PM 11098919 ER PT J AU Qin, H Tang, WM Lee, WW AF Qin, H Tang, WM Lee, WW TI Gyrocenter-gauge kinetic theory SO PHYSICS OF PLASMAS LA English DT Article ID GYROKINETIC PARTICLE SIMULATION; GUIDING CENTER MOTION; HAMILTONIAN-FORMULATION; FREE-ENERGY; EQUATIONS; PLASMAS; TRANSPORT; TOKAMAKS; MODES AB Gyrocenter-gauge kinetic theory is developed as an extension of the existing gyrokinetic theories. In essence, the formalism introduced here is a kinetic description of magnetized plasmas in the gyrocenter coordinates which is fully equivalent to the Vlasov-Maxwell system in the particle coordinates. In particular, provided the gyroradius is smaller than the scale-length of the magnetic field, it can treat high-frequency range as well as the usual low-frequency range normally associated with gyrokinetic approaches. A significant advantage of this formalism is that it enables the direct particle-in-cell simulations of compressional Alfven waves for magnetohydrodynamic (MHD) applications and of rf (radio frequency) waves relevant to plasma heating in space and laboratory plasmas. The gyrocenter-gauge kinetic susceptibility for arbitrary wavelength and arbitrary frequency electromagnetic perturbations in a homogeneous magnetized plasma is shown to recover exactly the classical result obtained by integrating the Vlasov-Maxwell system in the particle coordinates. This demonstrates that all the waves supported by the Vlasov-Maxwell system can be studied using the gyrocenter-gauge kinetic model in the gyrocenter coordinates. This theoretical approach is so named to distinguish it from the existing gyrokinetic theory, which has been successfully developed and applied to many important low-frequency and long parallel wavelength problems, where the conventional meaning of "gyrokinetic" has been standardized. Besides the usual gyrokinetic distribution function, the gyrocenter-gauge kinetic theory emphasizes as well the gyrocenter-gauge distribution function, which sometimes contains all the physics of the problems being studied, and whose importance has not been realized previously. The gyrocenter-gauge distribution function enters Maxwell's equations through the pull-back transformation of the gyrocenter transformation, which depends on the perturbed fields. The efficacy of the gyrocenter-gauge kinetic approach is largely due to the fact that it directly decouples particle's gyromotion from its gyrocenter motion in the gyrocenter coordinates. As in the case of kinetic theories using guiding center coordinates, obtaining solutions for this kinetic system involves only following particles along their gyrocenter orbits. However, an added advantage here is that unlike the guiding center formalism, the gyrocenter coordinates used in this theory involves both the equilibrium and the perturbed components of the electromagnetic field. In terms of solving the kinetic system using particle simulation methods, the gyrocenter-gauge kinetic approach enables the reduction of computational complexity without the loss of important physical content. (C) 2000 American Institute of Physics. [S1070-664X(00)00511-5]. C1 Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Qin, H (reprint author), Princeton Univ, Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 35 TC 29 Z9 29 U1 0 U2 9 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 NOV PY 2000 VL 7 IS 11 BP 4433 EP 4445 DI 10.1063/1.1309031 PG 13 WC Physics, Fluids & Plasmas SC Physics GA 374DW UT WOS:000165330000012 ER PT J AU Chacon, L Miley, GH Barnes, DC Knoll, DA AF Chacon, L Miley, GH Barnes, DC Knoll, DA TI Energy gain calculations in Penning fusion systems using a bounce-averaged Fokker-Planck model SO PHYSICS OF PLASMAS LA English DT Article ID INERTIAL-ELECTROSTATIC CONFINEMENT; PLASMA; FOCUS; TRAP; DENSITY AB In spherical Penning fusion devices, a spherical cloud of electrons, confined in a Penning-like trap, creates the ion-confining electrostatic well. Fusion energy gains for these systems have been calculated in optimistic conditions (i.e., spherically uniform electrostatic well, no collisional ion-electron interactions, single ion species) using a bounce-averaged Fokker-Planck (BAFP) model. Results show that steady-state distributions in which the Maxwellian ion population is dominant correspond to lowest ion recirculation powers (and hence highest fusion energy gains). It is also shown that realistic parabolic-like wells result in better energy gains than square wells, particularly at large well depths (> 100 kV). Operating regimes with fusion power to ion input power ratios (Q-value) > 100 have been identified. The effect of electron losses on the Q-value has been addressed heuristically using a semianalytic model, indicating that large Q-values are still possible provided that electron particle losses are kept small and well depths are large. (C) 2000 American Institute of Physics. [S1070- 664X(00)00711-4]. C1 Univ Illinois, Urbana, IL 61801 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Chacon, L (reprint author), Univ Illinois, 103 S Goodwin Ave, Urbana, IL 61801 USA. NR 19 TC 16 Z9 16 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 NOV PY 2000 VL 7 IS 11 BP 4547 EP 4560 PG 14 WC Physics, Fluids & Plasmas SC Physics GA 374DW UT WOS:000165330000023 ER PT J AU Chen, H Hawkes, NC Ingesson, LC von Hellermann, M Zastrow, KD Haines, MG Romanelli, M Peacock, NJ AF Chen, H Hawkes, NC Ingesson, LC von Hellermann, M Zastrow, KD Haines, MG Romanelli, M Peacock, NJ TI Poloidally asymmetric distribution of impurities in Joint European Torus plasmas SO PHYSICS OF PLASMAS LA English DT Article ID COLLISIONAL TOKAMAK PLASMA; PARTICLE-TRANSPORT; TOMOGRAPHY; JET AB Poloidally asymmetric distributions of nickel ions have been observed experimentally in Joint European Torus optimized shear tokamak plasmas following nickel laser injection experiments. Two types of asymmetries occur. In the first type of asymmetry, which has earlier been observed in high-confinement mode plasmas, nickel ions accumulate on the outboard side of the poloidal cross section. This can be explained well by fast toroidal plasma rotation driven by neutral beam injection. The second type of asymmetry was opposite in position: In a radio frequency heated optimized shear plasma, nickel ions have been seen to accumulate on the inboard side of the poloidal cross section. (C) 2000 American Institute of Physics. [S1070-664X(00)01611-6]. C1 Univ London Imperial Coll Sci Technol & Med, Blackett Lab, London SW7 2BZ, England. UKAEA Euratom Fus Assoc, Culham Sci Ctr, Abingdon OX14 3DB, Oxon, England. Jet Joint Undertaking, Joint European Torus, Abingdon OX14 3EA, Oxon, England. RP Chen, H (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 19 TC 13 Z9 13 U1 1 U2 2 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 NOV PY 2000 VL 7 IS 11 BP 4567 EP 4572 DI 10.1063/1.1311806 PG 6 WC Physics, Fluids & Plasmas SC Physics GA 374DW UT WOS:000165330000025 ER PT J AU Myra, JR D'Ippolito, DA Xu, XQ Cohen, RH AF Myra, JR D'Ippolito, DA Xu, XQ Cohen, RH TI Resistive modes in the edge and scrape-off layer of diverted tokamaks SO PHYSICS OF PLASMAS LA English DT Article ID X-POINT; BALLOONING STABILITY; MAGNETIC-FIELD; H-MODE; INSTABILITY; EQUILIBRIUM; SEPARATRIX; TURBULENCE; GYROKINETICS; TRANSPORT AB The linear behavior of resistive ballooning modes in the edge and scrape-off layer of diverted tokamaks is explored in the context of a collisional fluid model. It is shown that the large magnetic shear and small poloidal field in the X-point region act to increase the wave number, and hence the importance of resistivity, near the X point. The resulting "disconnection" of the eigenmodes across the X point profoundly influences the unstable spectrum. A new class of modes called resistive X-point (RX) modes exploits this synergism between resistivity and the X-point geometry, giving rise to robust growth rates at moderate-to-low mode numbers. Relative to an equivalent limited plasma, the diverted plasma is shown to be more unstable in the edge (inside the separatrix), and more stable in the scrape-off layer. (C) 2000 American Institute of Physics. [S1070- 664X(00)03911-2]. C1 Lodestar Res Corp, Boulder, CO 80301 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Myra, JR (reprint author), Lodestar Res Corp, 2400 Cent Ave,P-5, Boulder, CO 80301 USA. NR 31 TC 35 Z9 36 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 NOV PY 2000 VL 7 IS 11 BP 4622 EP 4631 DI 10.1063/1.1314623 PG 10 WC Physics, Fluids & Plasmas SC Physics GA 374DW UT WOS:000165330000032 ER PT J AU Sugiyama, LE Park, W AF Sugiyama, LE Park, W TI A nonlinear two-fluid model for toroidal plasmas SO PHYSICS OF PLASMAS LA English DT Article ID DRIFT-TEARING MODES; INTERNAL KINK MODE; TOKAMAK PLASMAS; KINETIC-THEORY; TRANSPORT; EQUATIONS; INSTABILITIES; MAGNETOFLUID; TOROIDICITY; SIMULATION AB A nonlinear numerical model for the two-fluid (electron and ion fluid) description of the evolution of a plasma in toroidal geometry, MH3D-T, is described. The model extends the "drift" ordering for small perturbations to arbitrary perturbation size. It is similar, but not identical, to the collisional Braginskii equations. The ion gyroviscous stress tensor, Hall terms, temperature diamagnetic drifts, and a separate electron pressure evolution are included. The model stresses the (fluid) parallel dynamics by solving the density evolution together with the temperature equations, including the thermal equilibration along the magnetic field. It includes the neoclassical, collisional parallel viscous forces for electrons and ions. The model has been benchmarked against the stabilizing effects of the ion diamagnetic drift omega (*i) on the m=1, n=1 reconnecting mode in a cylinder. The stabilization mechanism is shown to be poloidal rotation of the global kink flow of the plasma mass v(i) within q <1, relative to the location of the magnetic field X-point within the reconnection layer. The ion omega (*i)-drift is also shown to cause frequency-splitting for the toroidal Alfven eigenmode (TAE). Basic diamagnetic and neoclassical magnetohydrodynamic (MHD) effects on magnetic island evolution and rotation are discussed. The dynamics of the plasma along the magnetic field, when compressibility, parallel thermal conductivity, plasma density evolution, and full toroidal geometry are kept, are found to have strong effects on both linear growth rates and nonlinear evolution. The nonlinear coupling of magnetic islands, driven by perturbations of different toroidal mode number, is enhanced by the density evolution in both MHD and two-fluids. (C) 2000 American Institute of Physics. [S1070-664X(00)05310-6]. C1 MIT, Cambridge, MA 02139 USA. Princeton Univ, Plasma Phys Lab, Princeton, NJ 08543 USA. RP Sugiyama, LE (reprint author), MIT, 77 Massachusetts Ave, Cambridge, MA 02139 USA. NR 60 TC 45 Z9 45 U1 2 U2 14 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 NOV PY 2000 VL 7 IS 11 BP 4644 EP 4658 AR PII [S1070-664X(00)05310-6] DI 10.1063/1.1308083 PG 15 WC Physics, Fluids & Plasmas SC Physics GA 374DW UT WOS:000165330000034 ER PT J AU Fuchs, J Labaune, C Depierreux, S Tikhonchuk, VT Baldis, HA AF Fuchs, J Labaune, C Depierreux, S Tikhonchuk, VT Baldis, HA TI Stimulated Brillouin and Raman scattering from a randomized laser beam in large inhomogeneous collisional plasmas. I. Experiment SO PHYSICS OF PLASMAS LA English DT Article ID SCALE-LENGTH PLASMAS; EXPLODING FOIL PLASMAS; RANDOM-PHASE PLATES; ION-ACOUSTIC-WAVES; THOMSON SCATTERING; HOT-SPOTS; INSTABILITY; FILAMENTATION; SPECKLES; REFLECTIVITY AB Experiments have been conducted at the LULI (Laboratoire pour l'Utilisation des Lasers Intenses) multibeam laser facility to study in detail stimulated Brillouin (SBS) and Raman (SRS) scattering from an intense (mean average intensity up to 10(14) W/cm(2)) long (600 ps full width at half-maximum) laser beam interacting with thin exploded plastic foils. The plasmas are well characterized and the vacuum laser intensity distribution is well known due to using either random phase plates or polarization smoothing. Direct and simultaneous Thomson scattering measurements of the associated plasma waves allow us to obtain detailed information about the SBS and SRS temporal evolution and spatial localization. These data are being used to benchmark a statistical model of SBS and SRS from self-focused speckles. The results of this comparison will be presented in a companion paper. The analysis shows that both SBS and SRS are originated from self-focused speckles and reveals that plasma heating has an important effect on speckle self-focusing. (C) 2000 American Institute of Physics. [S1070- 664X(00)02011-5]. C1 Univ Paris 06, Ecole Polytech, CEA, Lab Utilisat Lasers Intenses,CNRS,UMR 7605, F-91128 Palaiseau, France. Univ Calif Lawrence Livermore Natl Lab, Inst Laser Sci & Applicat, Livermore, CA 94550 USA. RP Fuchs, J (reprint author), Univ Paris 06, Ecole Polytech, CEA, Lab Utilisat Lasers Intenses,CNRS,UMR 7605, F-91128 Palaiseau, France. RI Fuchs, Julien/D-3450-2016 OI Fuchs, Julien/0000-0001-9765-0787 NR 38 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 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD NOV PY 2000 VL 7 IS 11 BP 4659 EP 4668 DI 10.1063/1.1312183 PG 10 WC Physics, Fluids & Plasmas SC Physics GA 374DW UT WOS:000165330000035 ER PT J AU Sanford, TWL Olson, RE Mock, RC Chandler, GA Leeper, RJ Nash, TJ Ruggles, LE Simpson, WW Struve, KW Peterson, DL Bowers, RL Matuska, W AF Sanford, TWL Olson, RE Mock, RC Chandler, GA Leeper, RJ Nash, TJ Ruggles, LE Simpson, WW Struve, KW Peterson, DL Bowers, RL Matuska, W TI Dynamics of a Z-pinch x-ray source for heating inertial-confinement-fusion relevant hohlraums to 120-160 eV SO PHYSICS OF PLASMAS LA English DT Article ID NATIONAL-IGNITION-FACILITY; ARRAY Z-PINCH; TARGET DESIGN; Z-ACCELERATOR; WIRE-NUMBER; POWER; DRIVE; ENHANCEMENT; SIMULATIONS; INSIGHTS AB A Z-pinch radiation source has been developed that generates 60 +/- 20 kJ of x rays with a peak power of 13 +/-4 TW through a 4-mm-diam axial aperture on the Z facility. The source has heated National Ignition Facility-scale (6-mm-diam by 7-mm-high) hohlraums to 122 +/-6 eV and reduced-scale (4-mm-diam by 4-mm-high) hohlraums to 155 +/-8 eV-providing environments suitable for indirect-drive inertial confinement fusion studies. Eulerian-RMHC (radiation-magnetohydrodynamics code) simulations that take into account the development of the Rayleigh-Taylor instability in the r-z plane provide integrated calculations of the implosion, x-ray generation, and hohlraum heating, as well as estimates of wall motion and plasma fill within the hohlraums. Lagrangian-RMHC simulations suggest that the addition of a 6 mg/cm(3) CH2 fill in the reduced-scale hohlraum decreases hohlraum inner-wall velocity by similar to 40% with only a 3%-5% decrease in peak temperature, in agreement with measurements. (C) 2000 American Institute of Physics. [S1070-664X(00)05111-9]. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Sanford, TWL (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 56 TC 44 Z9 45 U1 0 U2 2 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 NOV PY 2000 VL 7 IS 11 BP 4669 EP 4682 AR PII [S1070-664X(00)05111-9] DI 10.1063/1.1316087 PG 14 WC Physics, Fluids & Plasmas SC Physics GA 374DW UT WOS:000165330000036 ER PT J AU Chacon, L Barnes, DC AF Chacon, L Barnes, DC TI Stability of thermal ions confined by rigid-rotor electron clouds in Penning fusion systems SO PHYSICS OF PLASMAS LA English DT Article ID PLASMA AB In the Penning fusion device, a spherical cloud of electrons, confined in a Penning-type trap, creates the ion-confining electrostatic well. Calculations performed with a bounce-averaged Fokker-Planck model have suggested that highest fusion energy gains in Penning fusion systems occur when the ion population is predominantly Maxwellian. However, the question arises about the stability of the electron cloud in the presence of thermal ions. Here, a stability analysis of rigid-rotor electrons confining thermal ions is performed. The results indicate that such configuration is absolutely stable to electrostatic perturbations for arbitrary rigid-rotor electron distributions. (C) 2000 American Institute of Physics. [S1070-664X(00)02711-7]. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Chacon, L (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 14 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 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD NOV PY 2000 VL 7 IS 11 BP 4774 EP 4777 PG 4 WC Physics, Fluids & Plasmas SC Physics GA 374DW UT WOS:000165330000048 ER PT J AU Rosenfeld, AH Kaarsberg, TM Romm, J AF Rosenfeld, AH Kaarsberg, TM Romm, J TI Technologies to reduce carbon dioxide emissions in the next decade SO PHYSICS TODAY LA English DT Article C1 US DOE, Washington, DC 20585 USA. NR 14 TC 3 Z9 3 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 NOV PY 2000 VL 53 IS 11 BP 29 EP 34 DI 10.1063/1.1333283 PG 6 WC Physics, Multidisciplinary SC Physics GA 367YC UT WOS:000090088900008 ER PT J AU Anderson, LE Li, AD Muslin, EH Schiffer, M Stevens, FJ AF Anderson, LE Li, AD Muslin, EH Schiffer, M Stevens, FJ TI Identifying redox-sensitive extra-chloroplastic enzymes by homology modeling SO PHYSIOLOGIA PLANTARUM LA English DT Review ID NADP-MALATE DEHYDROGENASE; LIGHT-DEPENDENT REGULATION; GLYCERALDEHYDE-3-PHOSPHATE DEHYDROGENASE; PLANT-MITOCHONDRIA; STRUCTURAL BASIS; DOMAIN-LOCKING; FRUCTOSE-1,6-BISPHOSPHATASE; IDENTIFICATION; DISULFIDE; INACTIVATION AB Homology modeling has been used to identify extra-chloroplastic enzymes that contain potential disulfide bonds. All of the higher plant fructose bisphosphatases and mitochondrial citrate synthases that have been tested to date, two glyceraldehyde-3-P dehydrogenases, two enolases and one lactate dehydrogenase, are redox-sensitive and may then be redox-regulated in vivo. Apparently, redox-sensitivity is not limited to the chloroplast. C1 Univ Illinois, Dept Biol Sci, Chicago, IL 60607 USA. Argonne Natl Lab, Biosci Div, Argonne, IL 60439 USA. RP Anderson, LE (reprint author), Univ Illinois, Dept Biol Sci, 845 W Taylor St, Chicago, IL 60607 USA. NR 30 TC 0 Z9 0 U1 1 U2 1 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0031-9317 J9 PHYSIOL PLANTARUM JI Physiol. Plant. PD NOV PY 2000 VL 110 IS 3 BP 296 EP 302 DI 10.1034/j.1399-3054.2000.1100302.x PG 7 WC Plant Sciences SC Plant Sciences GA 374XL UT WOS:000165369900002 ER PT J AU Supaphol, P Spruiell, JE Lin, JS AF Supaphol, P Spruiell, JE Lin, JS TI Isothermal melt crystallization and melting behaviour of syndiotactic polypropylene SO POLYMER INTERNATIONAL LA English DT Article DE syndiotactic polypropylene; isothermal crystallization; lamellar morphology; lamellar thickness; melting behaviour; equilibrium melting temperature ID ANGLE X-RAY; CRYSTAL-STRUCTURE; POLYMER CRYSTALLIZATION; ISOTACTIC POLYPROPYLENE; SINGLE-CRYSTALS; GROWTH-RATE; FORM-I; MORPHOLOGY; TEMPERATURE; FRACTIONS AB The lamellar morphological information and subsequent melting behaviour of syndiotactic polypropylene (s-PP) samples isothermally crystallized at crystallization temperatures ranging fi om 30 to 95 degreesC have been investigated using a combination of wide-angle X-ray diffraction (WAXD), small-angle X-ray scattering (SAXS) and differential scanning calorimetry (DSC) techniques. Three known methods for determining the equilibrium melting temperature T-m(o), namely the Gibbs-Thomson extrapolation, the linear Hoffman-Weeks extrapolation and the non-linear Hoffman-Weeks extrapolation, have been employed to evaluate this important thermodynamic parameter, and the results obtained are compared. Finally, an estimate of the equilibrium melting temperature for a perfect s-PP sample (T-m(o)) is given. (C) 2000 Society of Chemical Industry. C1 Chulalongkorn Univ, Petr & Petrochem Coll, Bangkok 10330, Thailand. Univ Tennessee, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Supaphol, P (reprint author), Chulalongkorn Univ, Petr & Petrochem Coll, Bangkok 10330, Thailand. RI Supaphol, Pitt/C-4353-2008 NR 45 TC 12 Z9 12 U1 0 U2 10 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 0959-8103 J9 POLYM INT JI Polym. Int. PD NOV PY 2000 VL 49 IS 11 BP 1473 EP 1482 DI 10.1002/1097-0126(200011)49:11<1473::AID-PI533>3.0.CO;2-9 PG 10 WC Polymer Science SC Polymer Science GA 370ZK UT WOS:000165153000030 ER PT J AU DeBiase, AE Taylor, BE AF DeBiase, AE Taylor, BE TI A new calanoid copepod species from South Carolina, USA: Aglaodiaptomus savagei (Crustacea : Copepoda : Calanoida : Diaptomidae) SO PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON LA English DT Article AB Aglaodiaptomus savagei, new species, was collected from a seasonal wetland pond in Kershaw County, South Carolina, U.S.A. Additional populations were found in eastern Noah Carolina, U.S.A. The female most closely resembles A. forbesi Light, 1938, and A. lintoni Forbes, 1893, but they are separated by the armament of the antennule, body length, and geographic range. Male A. savagei can be confused with male A. spatulocrenatus Pearse, 1906. Differences occur mainly in the ornamentation of the fifth leg, as well as segment sizes in the fifth leg. C1 Univ Georgia, Savannah River Ecol Lab, Aiken, SC 29802 USA. RP DeBiase, AE (reprint author), Univ Georgia, Savannah River Ecol Lab, PO Drawer E, Aiken, SC 29802 USA. NR 18 TC 0 Z9 0 U1 0 U2 0 PU BIOL SOC WASHINGTON PI WASHINGTON PA NAT MUSEUM NAT HIST SMITHSONIAN INST, WASHINGTON, DC 20560 USA SN 0006-324X EI 1943-6327 J9 P BIOL SOC WASH JI Proc. Biol. Soc. Wash. PD NOV 1 PY 2000 VL 113 IS 3 BP 681 EP 689 PG 9 WC Biology SC Life Sciences & Biomedicine - Other Topics GA 373JG UT WOS:000165285300011 ER PT J AU Aiken, DJ AF Aiken, DJ TI Antireflection coating design for series interconnected multi-junction solar cells SO PROGRESS IN PHOTOVOLTAICS LA English DT Article AB Antireflection coating design for multijunction solar cells be more challenging than in the single-junction case. Reasons for this are discussed. Analytical expressions used to optimize antireflection (AR) coatings fore single junction solar cells are extended for use in monolithic, series interconnected multi-junction solar cell AR coating design. The results is an analytical expression which relates the solar cell performance (through J(sc)) directly to the AR coating design through the device reflectance. It is also illustrated how AR coating design can be used to provide an additional degree of freedom for current matching multi-junction devices. Published in 2000 by John Wiley & Sons, Ltd. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Aiken, DJ (reprint author), Emcore Photovolta, 10420 Res Rd SE, Albuquerque, NM 87123 USA. NR 13 TC 15 Z9 15 U1 1 U2 8 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 NOV-DEC PY 2000 VL 8 IS 6 BP 563 EP 570 DI 10.1002/1099-159X(200011/12)8:6<563::AID-PIP327>3.0.CO;2-8 PG 8 WC Energy & Fuels; Materials Science, Multidisciplinary; Physics, Applied SC Energy & Fuels; Materials Science; Physics GA 392XT UT WOS:000166438400001 ER PT J AU Levi, D Albin, D King, D AF Levi, D Albin, D King, D TI Influence of surface composition on back-contact performance in CdTe/CdS PV devices SO PROGRESS IN PHOTOVOLTAICS LA English DT Article ID CDS/CDTE SOLAR-CELLS AB The atomic composition of the surface of the CdTe layer in a CdTe/CdS photovoltaic (PV) device has a significant influence on the quality of the electrical contact to this layer. This paper reports the results of a systemic study that correlates the composition of the back surface as measured with X-ray photoelectron spectroscopy (XPS) with pre-contact processing and device performance. We found that certain processing steps produce an oxide layer that degrades performance by producing a metal-oxide-semiconductor (MOS) contact, rather than the intended metal-semiconductor, Scottky barrier contact. We also found that the asdeposited CdTe film is cadmium-rich for several hundred angostroms at the back surface. This n-type layer may impede current flow for majority holes, degrading device performance. Published in 2000 by John Wiley & Sons, Ltd. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Levi, D (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 19 TC 15 Z9 15 U1 0 U2 5 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 1062-7995 J9 PROG PHOTOVOLTAICS JI Prog. Photovoltaics PD NOV-DEC PY 2000 VL 8 IS 6 BP 591 EP 602 DI 10.1002/1099-159X(200011/12)8:6<591::AID-PIP332>3.0.CO;2-P PG 12 WC Energy & Fuels; Materials Science, Multidisciplinary; Physics, Applied SC Energy & Fuels; Materials Science; Physics GA 392XT UT WOS:000166438400004 ER PT J AU Chang, PY Bjornstad, KA Chang, E McNamara, M Barcellos-Hoff, MH Lin, SP Aragon, G Polansky, JR Lui, GM Blakely, EA AF Chang, PY Bjornstad, KA Chang, E McNamara, M Barcellos-Hoff, MH Lin, SP Aragon, G Polansky, JR Lui, GM Blakely, EA TI Particle irradiation induces FGF2 expression in normal human lens cells SO RADIATION RESEARCH LA English DT Article ID FIBROBLAST-GROWTH-FACTOR; MOLECULAR-WEIGHT FORMS; HELIUM ION IRRADIATION; UVEAL MELANOMA; EPITHELIAL-CELLS; MESSENGER-RNA; DIFFERENTIATION; PROLIFERATION; LOCALIZATION; RADIATION AB Particle radiations, including both proton and helium-ion beams, have been used to successfully treat choroidal melanoma, but with the complication of radiation-induced cataract. We have investigated a role for radiation-induced changes in the expression of basic fibroblast growth factor (FGF2) gene expression as part of the mechanism(s) underlying lens cell injury associated with cataract. Normal human lens epithelial (HLE) cells were cultured in vitro on extracellular matrix (ECM) originated from bovine corneal endothelial cells. This study reports evidence for rapid but transient induction of FGF2 transcripts, an increase of between 5- and 8-fold, within 0.5 h after exposure to particle radiation, followed by another wave of increased transcription at 2-3 h postirradiation, Immunofluorescence results confirm the enhanced levels of FGF2 protein rapidly after exposure to protons or helium ions, followed by another wave of increased activity unique to helium at 6 h postirradiation, This second wave of increased immunoreactivity was not observed in the proton-irradiated samples, Total FGF2 protein analysis after helium-ion exposures shows induced expression of three FGF2 isoforms, with an increase of up to 2-fold in the 18-kDa low-molecular-weight species. Studies of the effects of protons on individual FGF2 protein isoforms are in progress. Several mechanisms involving a role for FGF2 in radiation-induced cataract are discussed. (C) 2000 by Radiation Research Society. C1 Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Life Sci, Berkeley, CA 94720 USA. SRI Int, Menlo Park, CA 94025 USA. Univ Calif San Francisco, Dept Ophthalmol, Cellular Pharmacol Lab, San Francisco, CA 94143 USA. Cellrex, San Francisco, CA 94116 USA. RP Blakely, EA (reprint author), Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Life Sci, MS 70A-1118, Berkeley, CA 94720 USA. FU NEI NIH HHS [EY10737] NR 54 TC 17 Z9 17 U1 0 U2 0 PU RADIATION RESEARCH SOC PI OAK BROOK PA 2021 SPRING RD, STE 600, OAK BROOK, IL 60521 USA SN 0033-7587 J9 RADIAT RES JI Radiat. Res. PD NOV PY 2000 VL 154 IS 5 BP 477 EP 484 DI 10.1667/0033-7587(2000)154[0477:PIIFEI]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 373GR UT WOS:000165281100001 PM 11025644 ER PT J AU Lawrence, JD AF Lawrence, JD TI Software qualification in safety applications SO RELIABILITY ENGINEERING & SYSTEM SAFETY LA English DT Article DE instrumentation and control; software; safety qualification; flowgraph; testing ID RELIABILITY AB The developers of safety-critical instrumentation and control systems must qualify the design of the components used, including the software in the embedded computer systems, in order to ensure that the component can be trusted to perform its safety function under the full range of operating conditions. There are well known ways to qualify analog systems using the facts that: (1) they are built from standard modules with known properties; (2) design documents are available and described in a well understood language; (3) the performance of the component is constrained by physics; and (4) physics models exist to predict the performance. These properties are not generally available for qualifying software, and one must fall back on extensive testing and qualification of the design process. Neither of these is completely satisfactory. The research reported here is exploring an alternative approach that is intended to permit qualification for an important subset of instrumentation software. The research goal is to determine if a combination of static analysis and limited testing can be used to qualify a class of simple, but practical, computer-based instrumentation components for safety application. These components are of roughly the complexity of a motion detector alarm controller. This goal is accomplished by identifying design constraints that enable meaningful analysis and testing. Once such design constraints are identified, digital systems can be designed to allow for analysis and testing, or existing systems may be tested for conformance to the design constraints as a first step in a qualification process. This will considerably reduce the cost and monetary risk involved in qualifying commercial components for safety-critical service. (C) 2000 Published by Elsevier Science Ltd. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Lawrence Livermore Natl Lab, POB 808,7000 E Ave,Mail Stop L-632, Livermore, CA 94550 USA. EM lawrence2@IInI.gov NR 27 TC 5 Z9 5 U1 0 U2 1 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0951-8320 EI 1879-0836 J9 RELIAB ENG SYST SAFE JI Reliab. Eng. Syst. Saf. PD NOV PY 2000 VL 70 IS 2 BP 167 EP 184 DI 10.1016/S0951-8320(00)00055-7 PG 18 WC Engineering, Industrial; Operations Research & Management Science SC Engineering; Operations Research & Management Science GA 358EK UT WOS:000089544100005 ER PT J AU Marinkovic, NS Adzic, AR Sullivan, M Kovacs, K Miller, LM Rousseau, DL Yeh, SR Chance, MR AF Marinkovic, NS Adzic, AR Sullivan, M Kovacs, K Miller, LM Rousseau, DL Yeh, SR Chance, MR TI Design and implementation of a rapid-mixer flow cell for time-resolved infrared microspectroscopy SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article ID CYTOCHROME-C; SYNCHROTRON-RADIATION; RELAXATION DYNAMICS; TERTIARY STRUCTURE; FAST EVENTS; SPECTROSCOPY; APOMYOGLOBIN; SECONDARY AB A rapid mixer for the analysis of reactions in the millisecond and submillisecond time domains by Fourier-transform infrared microspectroscopy has been constructed. The cell was tested by examination of cytochrome-c folding kinetics. The device allows collection of full infrared spectral data on millisecond and faster time scales subsequent to chemical jump reaction initiation. The data quality is sufficiently good such that spectral fitting techniques could be applied to analysis of the data. Thus, this method provides an advantage over kinetic measurements at single wavelengths using infrared laser or diode sources, particularly where band overlap exists. (C) 2000 American Institute of Physics. [S0034-6748(00)04911-X]. C1 Albert Einstein Coll Med, Ctr Synchrotron Biosci, Bronx, NY 11461 USA. Albert Einstein Coll Med, Dept Physiol & Biophys, Bronx, NY 11461 USA. Brookhaven Natl Lab, Natl Synchrotron Light Source, Upton, NY 11973 USA. RP Marinkovic, NS (reprint author), Albert Einstein Coll Med, Ctr Synchrotron Biosci, 1300 Morris Pk Ave, Bronx, NY 11461 USA. RI Marinkovic, Nebojsa/A-1137-2016 OI Marinkovic, Nebojsa/0000-0003-3579-3453 NR 13 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 NOV PY 2000 VL 71 IS 11 BP 4057 EP 4060 AR PII [S0034-6748(00)04911-X] DI 10.1063/1.1319342 PG 4 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 369TY UT WOS:000165084100011 ER PT J AU Bluhm, BK Gillig, KJ Russell, DH AF Bluhm, BK Gillig, KJ Russell, DH TI Development of a Fourier-transform ion cyclotron resonance mass spectrometer-ion mobility spectrometer SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article ID TRANSITION-METAL IONS; GAS-PHASE BASICITIES; HIGH MAGNETIC-FIELD; IONIZATION; PRESSURE; PEPTIDES; TRAP; DISSOCIATION; BIOMOLECULES; ENERGIES AB In an effort to incorporate ion-molecule reaction chemistry with ion mobility measurements we designed and constructed a novel instrument that combines a Fourier-transform ion cyclotron resonance (ICR) mass spectrometer with an ion mobility drift cell and a time-of-flight mass spectrometer. Measured mobilities for Ar+ and CO+ in helium are in excellent agreement with accepted literature values demonstrating that there are no adverse effects from the magnetic field on ion mobility measurements. Drift cell pressure, extracted from the measured mobility of Ar+ in helium, indicate that a pressure of similar to0.25 Torr is achieved in the present configuration. There are significant technological challenges associated with combining ICR and ion mobility that occurred during construction of this instrument, such as differential pumping and aperture alignment are presented. (C) 2000 American Institute of Physics. [S0034-6748(00)00310-5]. C1 Texas A&M Univ, Dept Chem, Lab Biol Mass Spectrometry, College Stn, TX 77842 USA. RP Bluhm, BK (reprint author), Univ Calif Los Alamos Natl Lab, Nucl Mat & Technol Div, POB 1663, Los Alamos, NM 87545 USA. RI Russell, David/C-3618-2015 OI Russell, David/0000-0003-0830-3914 NR 42 TC 33 Z9 34 U1 0 U2 3 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 NOV PY 2000 VL 71 IS 11 BP 4078 EP 4086 DI 10.1063/1.1288235 PG 9 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 369TY UT WOS:000165084100015 ER PT J AU Heeter, RF Fasoli, AF Ali-Arshad, S Moret, JM AF Heeter, RF Fasoli, AF Ali-Arshad, S Moret, JM TI Fast magnetic fluctuation diagnostics for Alfven eigenmode and magnetohydrodynamics studies at the Joint European Torus SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article ID DEUTERIUM-TRITIUM PLASMAS; ALPHA-PARTICLE TRANSPORT; JET DT PLASMAS; TOKAMAK; WAVES; TFTR; INSTABILITIES; PERFORMANCE; EXCITATION AB Alfven eigenmodes and other magnetohydrodynamic phenomena have been studied in tokamak plasmas at the Joint European Torus (JET) using a new eight-channel, 4 s, 1 MHz, 12-bit data acquisition system (KC1F) in conjunction with the JET fast Mirnov magnetic fluctuation pickup coils. To this end, the JET magnetic pickup coils were calibrated in the range 30-460 kHz using a new remote calibration technique which accounts for the presence of the first few LRC circuit resonances. Signal processing software has been developed to implement the calibration via digital filtering. A data analysis program has been written which produces spectrograms of fluctuation amplitude and toroidal mode number versus frequency and time, both interactively and for automatic overnight analyses. Modes with amplitudes deltaB/B greater than or equal to 10(-8) and toroidal mode numbers \n\< 32 are now routinely detected. Since KC1F data are now available for over 4000 JET discharges, a pulse-characterization database has been developed to help select pulses of interest for detailed analysis. (C) 2000 American Institute of Physics. [S0034-6748(00)01711-1]. C1 Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. MIT, Plasma Sci & Fus Ctr, Cambridge, MA 02139 USA. JET Joint Undertaking, Abingdon OX14 3EA, Oxon, England. Ecole Polytech Fed Lausanne, CRPP, CH-1015 Lausanne, Switzerland. RP Heeter, RF (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808, Livermore, CA 94551 USA. NR 41 TC 23 Z9 23 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 NOV PY 2000 VL 71 IS 11 BP 4092 EP 4106 DI 10.1063/1.1313797 PG 15 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 369TY UT WOS:000165084100017 ER PT J AU Terry, SD Hwang, DQ McLean, HS Horton, RD Evans, RW Baker, KL AF Terry, SD Hwang, DQ McLean, HS Horton, RD Evans, RW Baker, KL TI The "Compact Toroid Injection Experiment" tomographic imaging system SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article ID PHOTODIODES; PENETRATION; TOKAMAK; PLASMAS AB The design, construction and operation of a tomographic imaging system on the Compact Toroid Injection Experiment is described. The system measures the total radiated power over energies from visible light up into the extreme ultraviolet. It then reconstructs two dimensional profiles from the data. The reconstruction routine is based on a method known as second order regularization which finds a compromise between smoothness and fit to the data. This method was found to have the best overall fidelity to test images. The hardware and overall reconstruction were calibrated using two different sources. First results from the system under real experimental conditions are presented. (C) 2000 American Institute of Physics. [S0034-6748(00)04111-3]. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Terry, SD (reprint author), Univ Calif Los Angeles, Dept Elect Engn, Los Angeles, CA 90095 USA. NR 13 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 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD NOV PY 2000 VL 71 IS 11 BP 4119 EP 4126 DI 10.1063/1.1318920 PG 8 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 369TY UT WOS:000165084100019 ER PT J AU Balaban, AT Randic, M AF Balaban, AT Randic, M TI Proposal for using an untapped source of citations characterizing scientific areas SO SCIENTOMETRICS LA English DT Article ID CENTROSYMMETRIC SPACE GROUPS; PHASE DETERMINATION AB Bibliographies of "reference books", namely Encyclopedias, Comprehensive Treatises, and Advanced Textbooks constitute a valuable source of information about seminal papers in various branches of science. Examples are given mainly for chemistry, but other areas might be treated similarly.Bibliographies of "reference books", namely Encyclopedias, Comprehensive Treatises, and Advanced Textbooks constitute a valuable source of information about seminal papers in various branches of science. Examples are given mainly for chemistry, but other areas might be treated similarly. C1 Texas A&M Univ, Galveston, TX 77553 USA. Iowa State Univ, Dept Energy, Ames Lab, Ames, IA 50011 USA. RP Balaban, AT (reprint author), Texas A&M Univ, Galveston, TX 77553 USA. EM balabana@tamug.tamu.edu NR 23 TC 1 Z9 1 U1 1 U2 3 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0138-9130 J9 SCIENTOMETRICS JI Scientometrics PD NOV-DEC PY 2000 VL 49 IS 3 BP 517 EP 521 DI 10.1023/A:1010597925625 PG 5 WC Computer Science, Interdisciplinary Applications; Information Science & Library Science SC Computer Science; Information Science & Library Science GA 379QQ UT WOS:000165654300010 ER PT J AU Kaminski, MD Nunez, L Pourfarzaneh, M Negri, C AF Kaminski, MD Nunez, L Pourfarzaneh, M Negri, C TI Cesium separation from contaminated milk using magnetic particles containing crystalline silicotitanates SO SEPARATION AND PURIFICATION TECHNOLOGY LA English DT Article DE cesium separation; magnetic particles; crystalline silicotitanates; milk purification ID ASSISTED CHEMICAL-SEPARATION; FERROMAGNETIC MICROPARTICLES; EXTRACTANTS AB The Chernobyl nuclear reactor disaster in 1986 contaminated vast regions of prime grazing land. Subsequently, milk produced in the region has been contaminated with small amounts of the long-lived fission product cesium-137, and the Ukraine is seeking to deploy a simple separation process that will remove the Cs and preserve the nutritional value of the milk. Tiny magnetic particles containing crystalline silicotitanates (CST) have been manufactured and rested to this end. The results show that partitioning efficiency is optimized with low ratios of particle mass to volume. To achieve 90% Cs decontamination in a single-stage process, <3 g of magnetic CST per 1 milk is sufficient with a 30-min mixing time. A two-stage process would utilize < 0.4 g/l per stage. The modeling of the magnetic CST system described herein can be achieved rather simply which is important for deployment in the affected Ukraine region. (C) 2000 Published by Elsevier Science B.V. C1 Argonne Natl Lab, Div Chem Technol, Waste Management Dept, Argonne, IL 60439 USA. Cortex Biochem Inc, San Leandro, CA 94577 USA. Argonne Natl Lab, Div Energy Syst, Argonne, IL 60439 USA. RP Nunez, L (reprint author), Argonne Natl Lab, Div Chem Technol, Waste Management Dept, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 17 TC 5 Z9 5 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 1383-5866 J9 SEP PURIF TECHNOL JI Sep. Purif. Technol. PD NOV 1 PY 2000 VL 21 IS 1-2 BP 1 EP 8 DI 10.1016/S1383-5866(99)00062-3 PG 8 WC Engineering, Chemical SC Engineering GA 376TT UT WOS:000165473400001 ER PT J AU Adamian, ZN Hakhoyan, AP Aroutiounian, VM Barseghian, RS Touryan, K AF Adamian, ZN Hakhoyan, AP Aroutiounian, VM Barseghian, RS Touryan, K TI Investigations of solar cells with porous silicon as antireflection layer SO SOLAR ENERGY MATERIALS AND SOLAR CELLS LA English DT Article DE porous silicon; solar cells; hydrofluoric acid; antireflection coating AB The possibility of using porous silicon layers as antireflection coating instead of the antireflection coatings in common silicon solar cells was investigated. A technology for the manufacture of porous silicon antireflection layers was developed. The comparison of the photovoltaic and optical characteristics of investigated samples of solar cells with ZnS antireflection coating and with porous silicon antireflection coating is presented. It is shown that the formation of the porous layer under optimal technological regimes leads to significant improvement of the main photovoltaic parameters-short-circuit current and open-circuit voltage. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Yerevan State Univ, Dept Phys Semicond, Yerevan 375049, Armenia. Natl Renewable Energy Lab, Golden, CO USA. RP Aroutiounian, VM (reprint author), Yerevan State Univ, Dept Phys Semicond, 1 Manoukian Str, Yerevan 375049, Armenia. NR 6 TC 29 Z9 32 U1 0 U2 11 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0927-0248 J9 SOL ENERG MAT SOL C JI Sol. Energy Mater. Sol. Cells PD NOV PY 2000 VL 64 IS 4 BP 347 EP 351 DI 10.1016/S0927-0248(00)00221-X PG 5 WC Energy & Fuels; Materials Science, Multidisciplinary; Physics, Applied SC Energy & Fuels; Materials Science; Physics GA 358YY UT WOS:000089585800005 ER PT J AU Aiken, DJ AF Aiken, DJ TI High performance anti-reflection coatings for broadband multi-junction solar cells SO SOLAR ENERGY MATERIALS AND SOLAR CELLS LA English DT Article DE antireflection coating; multi-junction; solar weighted reflectance; herpin equivalent layers ID SINGLE AB The success of bandgap engineering has made high-efficiency broadband multi-junction solar cells possible with photo-response out to the band edge of germanium. Modeling has been conducted which suggests that current double-layer antireflection coating technology is not adequate for these devices in certain cases. Approaches for the development of higher performance antireflection coatings are examined. A new antireflection coating structure based on the use of Herpin equivalent layers is presented. Optical modeling of the new AR coating suggests a decrease in the solar weighted reflectance of 2.5% absolute over typically used double-layer antireflection coatings. This structure requires no additional optical material development and characterization because no new optical materials are necessary. Experimental results and a sensitivity analysis are presented. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Aiken, DJ (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 17 TC 54 Z9 57 U1 3 U2 15 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0927-0248 J9 SOL ENERG MAT SOL C JI Sol. Energy Mater. Sol. Cells PD NOV PY 2000 VL 64 IS 4 BP 393 EP 404 DI 10.1016/S0927-0248(00)00253-1 PG 12 WC Energy & Fuels; Materials Science, Multidisciplinary; Physics, Applied SC Energy & Fuels; Materials Science; Physics GA 358YY UT WOS:000089585800010 ER PT J AU Garzon, FH Mukundan, R Brosha, EL AF Garzon, FH Mukundan, R Brosha, EL TI Solid-stale mixed potential gas sensors: theory. experiments and challenges SO SOLID STATE IONICS LA English DT Article; Proceedings Paper CT 12th International Conference on Solid State Ionics CY JUN 06-12, 1999 CL HALKIDIKI, GREECE SP Minist Cultural Affairs, Minist Educ, Minist Macedonia & Thrace, Gen Secretariat Res & Technol, Univ Patras, Res Comm, Aristotle Univ Thessaloniki, Univ Thessaly, Patras Sci Pk, Chem Process Engn Res Inst, Natl Bank Greece, Commercial Bank Greece, Agr Bank Greece, Athenian Brewry SA, Patras Plant, LPC Hellas, Leader Books SA, GlaxoWellcome, George P Vasilopoulos SA, Hlthcon Ltd, Energizer, ONR, Elefctrochem Soc, High Temperature Mat Div DE mixed potential sensors; carbon monoxide sensors; sensor theory; metal oxide sensors; electrocatalysis ID STABILIZED ZIRCONIA; CARBON-MONOXIDE; HYDROGEN SENSOR; OXIDE ELECTRODE AB Solid-state mixed potential electrochemical sensors sense gases using differential electrocatalysis on dissimilar electrode materials. The response theory is typically expressed in terms of models invoking Butler-Volmer kinetics at high overpotentials (Tafel behavior). This model is not adequate for describing all types of mixed potential sensor responses. For low concentrations of analyte gas, mass transport limitations must also be considered. Experiments with sensors with air reference electrodes also demonstrate the importance of low overpotential oxygen reduction kinetics in establishing the device response. A sensor response model that predicts a linear relationship between response voltage and analyte gas concentration is derived. The development of oxide electrode based devices offers improved long-term response stability over metal electrode based devices. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Elect & Electrochem Mat & Devices Grp, Los Alamos, NM 87545 USA. RP Garzon, FH (reprint author), Univ Calif Los Alamos Natl Lab, Elect & Electrochem Mat & Devices Grp, Mail Stop D429, Los Alamos, NM 87545 USA. NR 13 TC 163 Z9 164 U1 4 U2 41 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-2738 J9 SOLID STATE IONICS JI Solid State Ion. PD NOV PY 2000 VL 136 SI SI BP 633 EP 638 DI 10.1016/S0167-2738(00)00348-9 PG 6 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA 385GZ UT WOS:000165996600097 ER PT J AU Hormes, J Pantelouris, M Balazs, GB Rambabu, B AF Hormes, J Pantelouris, M Balazs, GB Rambabu, B TI X-ray absorption near edge structure (XANES) measurements of ceria-based solid electrolytes SO SOLID STATE IONICS LA English DT Article; Proceedings Paper CT 12th International Conference on Solid State Ionics CY JUN 06-12, 1999 CL HALKIDIKI, GREECE SP Minist Cultural Affairs, Minist Educ, Minist Macedonia & Thrace, Gen Secretariat Res & Technol, Univ Patras, Res Comm, Aristotle Univ Thessaloniki, Univ Thessaly, Patras Sci Pk, Chem Process Engn Res Inst, Natl Bank Greece, Commercial Bank Greece, Agr Bank Greece, Athenian Brewry SA, Patras Plant, LPC Hellas, Leader Books SA, GlaxoWellcome, George P Vasilopoulos SA, Hlthcon Ltd, Energizer, ONR, Elefctrochem Soc, High Temperature Mat Div DE solid electrolytes; solid oxide fuel cells (SOFCs); doped ceria; X-ray absorption near edge structure (XANES) AB The X-ray absorption near edge structure (XANES) spectra of a series of ceria samples doped with trivalent rare earth oxide have been measured at the L-III edges of the dopants and the cerium. These spectra give information on the valency of the excited atom and the geometric structure of the direct neighborhood of this atom. By comparing the XANES spectra of the dopants with those of the pure oxides, differences in thr way the dopants are incorporated into the ceria lattice can be observed. These differences together with the mismatch of the ionic radii of the dopants compared to Ce, seem to be responsible for the decreasing ionic conductivity of the lighter rare earth dopants. For Pr, the spectra indicate a partial oxidation to Pr-44 leading to a reduced conductivity. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Southern Univ, Surface Sci Spect & Solid State Ion Lab, Baton Rouge, LA 70813 USA. Univ Calif Lawrence Livermore Natl Lab, Chem & Mat Sci Directorate, Livermore, CA 94550 USA. Ctr Adv Microstruct & Devices, Baton Rouge, LA 70809 USA. Univ Bonn, Inst Phys, D-53115 Bonn, Germany. RP Rambabu, B (reprint author), Southern Univ, Surface Sci Spect & Solid State Ion Lab, Baton Rouge, LA 70813 USA. NR 17 TC 25 Z9 29 U1 0 U2 8 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-2738 J9 SOLID STATE IONICS JI Solid State Ion. PD NOV PY 2000 VL 136 SI SI BP 945 EP 954 DI 10.1016/S0167-2738(00)00533-6 PG 10 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA 385GZ UT WOS:000165996600140 ER PT J AU Wilmer, D Jorgensen, JD Wuensch, BJ AF Wilmer, D Jorgensen, JD Wuensch, BJ TI Two-dimensional silver fast-ion conduction in (LaO)AgS SO SOLID STATE IONICS LA English DT Article; Proceedings Paper CT 12th International Conference on Solid State Ionics CY JUN 06-12, 1999 CL HALKIDIKI, GREECE SP Minist Cultural Affairs, Minist Educ, Minist Macedonia & Thrace, Gen Secretariat Res & Technol, Univ Patras, Res Comm, Aristotle Univ Thessaloniki, Univ Thessaly, Patras Sci Pk, Chem Process Engn Res Inst, Natl Bank Greece, Commercial Bank Greece, Agr Bank Greece, Athenian Brewry SA, Patras Plant, LPC Hellas, Leader Books SA, GlaxoWellcome, George P Vasilopoulos SA, Hlthcon Ltd, Energizer, ONR, Elefctrochem Soc, High Temperature Mat Div DE two-dimensional fast-ion conduction; neutron diffraction ID ELECTRICAL-PROPERTIES AB The silver fast-ion conductor (LaO)AgS was examined in temperature-dependent so impedance and time-of-Right neutron diffraction experiments. Comparison of our conductivity data with those published earlier suggests that the presence of unreacted Ag2S resulting From different sample preparation methods is the possible reason for severe discrepancies in the conductivity data of other authors. Anisotropic temperature factors obtained by Rietveld analysis of our neutron diffraction data indicate enhanced silver ion mobility in the a-b plane of the tetragonal structure. The observed silver ion density shows that the preferred conduction path is via interstitial (1/2 1/2 1/2) sites, i.e. along < 110 >. (LaO)AgS is a two-dimensional silver fast-ion conductor. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Munster, Inst Phys Chem, D-48149 Munster, Germany. Argonne Natl Lab, IPNS, Argonne, IL 60439 USA. MIT, Dept Mat Sci & Engn, Cambridge, MA USA. RP Wilmer, D (reprint author), Univ Munster, Inst Phys Chem, Schlosspl 4-7, D-48149 Munster, Germany. NR 9 TC 9 Z9 9 U1 2 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-2738 J9 SOLID STATE IONICS JI Solid State Ion. PD NOV PY 2000 VL 136 SI SI BP 961 EP 966 DI 10.1016/S0167-2738(00)00512-9 PG 6 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA 385GZ UT WOS:000165996600142 ER PT J AU Bychkov, E Price, DL AF Bychkov, E Price, DL TI Neutron diffraction studies of Ag2S-As2S3 glasses in the percolation and modifier-controlled domains SO SOLID STATE IONICS LA English DT Article; Proceedings Paper CT 12th International Conference on Solid State Ionics CY JUN 06-12, 1999 CL HALKIDIKI, GREECE SP Minist Cultural Affairs, Minist Educ, Minist Macedonia & Thrace, Gen Secretariat Res & Technol, Univ Patras, Res Comm, Aristotle Univ Thessaloniki, Univ Thessaly, Patras Sci Pk, Chem Process Engn Res Inst, Natl Bank Greece, Commercial Bank Greece, Agr Bank Greece, Athenian Brewry SA, Patras Plant, LPC Hellas, Leader Books SA, GlaxoWellcome, George P Vasilopoulos SA, Hlthcon Ltd, Energizer, ONR, Elefctrochem Soc, High Temperature Mat Div ID CHALCOGENIDE GLASSES; SE AB High-resolution neutron diffraction experiments at scattering vectors up to 40 Angstrom (-1) have been carried out for the Ag2S-As2S3 glassy system in order to find differences in the network structural organisation within the percolation and modifier-controlled domains. No significant changes in the short- and intermediate-range order are found in the critical percolation region (x less than or equal to 1.2 at.% Ag): the intensity and position of the first sharp diffraction peak (FSDP) exhibit relatively small changes as a function of the silver content, and the trigonal arsenic local coordination and two-fold coordinated sulphur species remain essentially intact. These observations agree very well with a model of host network-dependent percolative ion transport. In the modifier-controlled domain (x > 10-15 at.% Ag), one observes nearly complete disappearance of the FSDP at 1.25-1.35 Angstrom (-1) and remarkable changes in the short-range order, in particular, characteristic Ag-Ag correlations at approximate to 3 Angstrom, indicating a predominant role of Ag-containing structural units in the modified network organisation. These structural units and their interconnections seem to be similar for many silver-rich chalcogenide glasses, in which the Ag+ ion transport depends on the Ag content but not on the host matrix. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Littoral, F-59140 Dunkerque, France. Argonne Natl Lab, Argonne, IL 60439 USA. RP Bychkov, E (reprint author), Univ Littoral, F-59140 Dunkerque, France. RI Price, David Long/A-8468-2013 NR 21 TC 25 Z9 25 U1 1 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-2738 J9 SOLID STATE IONICS JI Solid State Ion. PD NOV PY 2000 VL 136 SI SI BP 1041 EP 1048 DI 10.1016/S0167-2738(00)00525-7 PG 8 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA 385GZ UT WOS:000165996600154 ER PT J AU Bates, JB Dudney, NJ Neudecker, B Ueda, A Evans, CD AF Bates, JB Dudney, NJ Neudecker, B Ueda, A Evans, CD TI Thin-film lithium and lithium-ion batteries SO SOLID STATE IONICS LA English DT Article; Proceedings Paper CT 12th International Conference on Solid State Ionics CY JUN 06-12, 1999 CL HALKIDIKI, GREECE SP Minist Cultural Affairs, Minist Educ, Minist Macedonia & Thrace, Gen Secretariat Res & Technol, Univ Patras, Res Comm, Aristotle Univ Thessaloniki, Univ Thessaly, Patras Sci Pk, Chem Process Engn Res Inst, Natl Bank Greece, Commercial Bank Greece, Agr Bank Greece, Athenian Brewry SA, Patras Plant, LPC Hellas, Leader Books SA, GlaxoWellcome, George P Vasilopoulos SA, Hlthcon Ltd, Energizer, ONR, Elefctrochem Soc, High Temperature Mat Div DE solid-state thin-film battery; lithium battery; lithium-ion battery; LiCoO2; LiMn2O4; hysteresis ID NICKEL OXIDES LI-X(MNYNI1-Y)(2-X)O-2; LIMN2O4 ELECTRODES; CATHODES AB Research over the last decade at Oak Ridge National Laboratory has led to the development of solid-state thin-film lithium and lithium-ion batteries. The batteries, which are less than 15 mum thick, have important applications in a variety of consumer and medical products, and they are useful research tools in characterizing the properties of lithium intercalation compounds in thin-film form. The batteries consist of cathodes that are crystalline or nanocrystalline oxide-based lithium intercalation compounds such as LiCoO2 and LiMn2O4, and anodes of lithium metal, inorganic compounds such as silicon-tin oxynitrides, Sn3N4 and Zn3N2, or metal films such as Cu in which the anode is formed by lithium plating on the initial charge. The electrolyte is a glassy lithium phosphorus oxynitride ('Lipon'). Cells with crystalline LiCoO2 cathodes can deliver up to 30% of their maximum capacity between 4.2 and 3 V at discharge currents of 10 mA/cm(2), and at more moderate discharge-charge rates, the capacity decreases by negligible amounts over thousands of cycles. Thin films of crystalline lithium manganese oxide with the general composition Li1+xMn2-yO4 exhibit on the initial charge significant capacity at 5 V and, depending on the deposition process, at 4.6 V as well, as a consequence of the manganese deficiency-lithium excess. The 5-V plateau is believed to be due to oxidation Mn of ions to valence states higher than + 4 accompanied by a rearrangement of the lattice. The gap between the discharge-charge curves of cells with as-deposited nanocrystalline Li1+xMn2-yO4 cathodes is due to a true hysteresis as opposed to a kinetically hindered relaxation observed with the highly crystalline films. This behavior was confirmed by observing classic scanning curves on charge and discharge at intermediate stages of insertion and extraction of Li- ions. Extended cycling of lithium cells with these cathodes at 25 and 100 degreesC leads to grain growth and evolution of the charge-discharge profiles toward those characteristic of well crystallized films. (C) 2000 Published by Elsevier Science B.V. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Dudney, NJ (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. RI Dudney, Nancy/I-6361-2016 OI Dudney, Nancy/0000-0001-7729-6178 NR 32 TC 566 Z9 600 U1 65 U2 675 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-2738 J9 SOLID STATE IONICS JI Solid State Ion. PD NOV PY 2000 VL 135 IS 1-4 SI SI BP 33 EP 45 DI 10.1016/S0167-2738(00)00327-1 PG 13 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA 382ZG UT WOS:000165856800005 ER PT J AU Singhal, SC AF Singhal, SC TI Advances in solid oxide fuel cell technology SO SOLID STATE IONICS LA English DT Article; Proceedings Paper CT 12th International Conference on Solid State Ionics CY JUN 06-12, 1999 CL HALKIDIKI, GREECE SP Minist Cultural Affairs, Minist Educ, Minist Macedonia & Thrace, Gen Secretariat Res & Technol, Univ Patras, Res Comm, Aristotle Univ Thessaloniki, Univ Thessaly, Patras Sci Pk, Chem Process Engn Res Inst, Natl Bank Greece, Commercial Bank Greece, Agr Bank Greece, Athenian Brewry SA, Patras Plant, LPC Hellas, Leader Books SA, GlaxoWellcome, George P Vasilopoulos SA, Hlthcon Ltd, Energizer, ONR, Elefctrochem Soc, High Temperature Mat Div DE fuel cells; oxide; electricity (power) generation; performance; electrolyte; electrodes; gas turbine; cost ID FILMS AB High temperature solid oxide fuel cells (SOFCs) offer a clean, pollution-free technology to electrochemically generate electricity at high efficiencies. These fuel cells provide many advantages over traditional energy conversion systems including high efficiency, reliability, modularity, fuel adaptability, and very low levels of NOx and SOx emissions. Furthermore, because of their high temperature of operation (similar to 1000 degreesC), natural gas fuel can be reformed within the cell stack eliminating the need for an expensive, external reformer. Also, pressurized SOFCs can be successfully used as replacements for combustors in gas turbines; such hybrid SOFC-gas turbine power systems are expected to reach efficiencies over 70%. This paper reviews the materials and fabrication methods used for the different cell components, and discusses the performance of cells fabricated using these materials; it also discusses the materials and processing studies that are under investigation to reduce the cell cost. Finally, the paper summarizes the recently built power generation systems that employed state-of-the-art SOFCs. A new design SOFC that combines the seal-less feature of tubular cells and a flattened air electrode with integral ribs is also described; this new design has a shortened current path and hence lower cell resistance and higher power output than tubular cells. (C) 2000 Published by Elsevier Science BN. C1 Siemens Westinghouse Power Corp, Ctr Sci & Technol, Pittsburgh, PA 15235 USA. RP Singhal, SC (reprint author), Pacific NW Natl Lab, 902 Battelle Blvd,POB 999, Richland, WA 99352 USA. NR 12 TC 763 Z9 801 U1 40 U2 341 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-2738 J9 SOLID STATE IONICS JI Solid State Ion. PD NOV PY 2000 VL 135 IS 1-4 SI SI BP 305 EP 313 DI 10.1016/S0167-2738(00)00452-5 PG 9 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA 382ZG UT WOS:000165856800042 ER PT J AU Mirkarimi, PB Baker, SL Wall, MA Kearney, PA Stearns, DG AF Mirkarimi, PB Baker, SL Wall, MA Kearney, PA Stearns, DG TI Defects from substrate particles depend on the sputter deposition process SO SOLID STATE TECHNOLOGY LA English DT Article ID EXTREME-ULTRAVIOLET LITHOGRAPHY; MASK BLANKS; FILMS AB With successive IC generations, thin-film defects nucleated small particles become a greater concern. We have observed that the angle of incidence of the deposition flux can have a major effect on the evolution of film defects nucleated by small substrate particles. Using a new technique to deposit small spheres on Si wafers, we observed that a significant reduction in defect size occurs when near-normal-incidence ion-beam sputtering is used to deposit thin films, and a significant increase in defect size occurs when off-normal-incidence ion-beam sputtering or conventional magnetron sputtering is used to deposit the films. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. OS Associates, Mt View, CA USA. RP Mirkarimi, PB (reprint author), Univ Calif Lawrence Livermore Natl Lab, MS L-395,7000 East Ave, Livermore, CA 94550 USA. NR 14 TC 10 Z9 10 U1 1 U2 1 PU PENNWELL PUBL CO SOLID STATE TECHNOLOGY OFFICE PI NASHUA PA TEN TARA BLVD 5TH FLOOR, NASHUA, NH 03062-2801 USA SN 0038-111X J9 SOLID STATE TECHNOL JI Solid State Technol. PD NOV PY 2000 VL 43 IS 11 BP 95 EP + PG 4 WC Engineering, Electrical & Electronic; Physics, Applied; Physics, Condensed Matter SC Engineering; Physics GA 373AX UT WOS:000165267200018 ER PT J AU Bushaw, BA Nortershauser, W AF Bushaw, BA Nortershauser, W TI Resonance ionization spectroscopy of stable strontium isotopes and Sr-90 via 5s(2) S-1(0) -> 5s5p P-1(1) -> 5s5d D-1(2) -> 5s11f F-1(3) -> Sr+ SO SPECTROCHIMICA ACTA PART B-ATOMIC SPECTROSCOPY LA English DT Article DE mass spectrometry; radionuclides; strontium; trace analysis ID MASS-SPECTROMETRY; HYPERFINE-STRUCTURE; ENVIRONMENTAL-SAMPLES; LASER SPECTROSCOPY; CHARGE RADII; TRANSITIONS; STATES; SR-87; CA-41 AB Single-, double- and triple-resonance ionization in the 5s(21)S(0) --> 5s5p P-1(1) --> 5s5d D-1(2) --> 5s11f F-1(3) --> S-r+ system of strontium was investigated to achieve an efficient and highly selective ionization scheme for ultra-trace detection of the radioisotope Sr-90. Isotope shifts and hyperfine structure for all stable isotopes of Sr were measured in all three resonant transitions. Good agreement with previous data was found in the 5s(21)S(0) --> 5s5p P-1(1) transition and precision was improved by approximately one order of magnitude. Isotope shifts, including that for Sr-90, and hyperfine structure in the two- and three-photon transitions were measured for the first time. The double- and triple-resonance schemes were characterized with respect to their isotopic selectivity for detection of Sr-90. The double-resonance process offers an optical selectivity of 2 x 10(4), while unfavorable isotope shifts in the triple-resonance process limit its selectivity to similar to 100. Using double-resonance ionization combined with mass spectrometric detection, an overall detection efficiency of > 10(-5), a selectivity > 10(10), and a detection limit of 0.7 fg Sr-90 in samples with a 10(10) excess of stable Sr isotopes have been demonstrated. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Bushaw, BA (reprint author), Pacific NW Natl Lab, POB 999, Richland, WA 99352 USA. RI Nortershauser, Wilfried/A-6671-2013 OI Nortershauser, Wilfried/0000-0001-7432-3687 NR 35 TC 18 Z9 18 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0584-8547 J9 SPECTROCHIM ACTA B JI Spectroc. Acta Pt. B-Atom. Spectr. PD NOV 1 PY 2000 VL 55 IS 11 BP 1679 EP 1692 DI 10.1016/S0584-8547(00)00269-X PG 14 WC Spectroscopy SC Spectroscopy GA 375RA UT WOS:000165414000004 ER PT J AU Borisov, OV Mao, XL Russo, RE AF Borisov, OV Mao, XL Russo, RE TI Effects of crater development on fractionation and signal intensity during laser ablation inductively coupled plasma mass spectrometry SO SPECTROCHIMICA ACTA PART B-ATOMIC SPECTROSCOPY LA English DT Article DE inductively coupled plasma mass spectrometry; laser ablation; elemental fractionation ID ATOMIC EMISSION-SPECTROMETRY; ELEMENTAL FRACTIONATION; ICP-MS; VAPORIZATION; GLASS; SPECTROSCOPY; SILICA; COPPER AB The effects of crater development on ICP-MS signal intensities and elemental fractionation have been presented in this work. Craters formed after repetitive 266-nm Nd/YAG laser ablation with 1.0-mJ pulses had a cone-like shape. The laser ablation rate (ng/s) depended on the laser irradiance (laser pulse energy per unit time and unit area), decreasing as irradiance increased. In contrast, the particle entrainment/transport efficiency did not significantly change with irradiance. As the crater-aspect ratio (depth/diameter) increased above some threshold value of six, the Pb/U elemental ratio departed from the stoichiometric value. However, good stoichiometry of ablated mass could be achieved when experimental conditions were carefully selected. The exact mechanism of how crater development affects fractionation is not well understood. In this work, actual irradiance was introduced instead of a nominal value. Actual irradiance decreased as the crater deepened due to changes of the effective area, sampled by the laser beam. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Russo, RE (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. NR 26 TC 75 Z9 75 U1 1 U2 17 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0584-8547 J9 SPECTROCHIM ACTA B JI Spectroc. Acta Pt. B-Atom. Spectr. PD NOV 1 PY 2000 VL 55 IS 11 BP 1693 EP 1704 DI 10.1016/S0584-8547(00)00272-X PG 12 WC Spectroscopy SC Spectroscopy GA 375RA UT WOS:000165414000005 ER PT J AU Baker, C Glad, S AF Baker, C. Glad, S. TI Simulation-Driven Design Helps Create Vibration-Free Control System for a Robot with a 30 Foot Long Arm SO STRAIN LA English DT Article C1 [Baker, C.] Pacific NW Natl Lab, Richland, WA 99352 USA. [Glad, S.] Struct Informat, Birmingham, MI USA. RP Baker, C (reprint author), Pacific NW Natl Lab, Richland, WA 99352 USA. FU U.S. Department of Energy [DE-AC06-67RLO1830] FX Pacific Northwest National Laboratory is operated for the U.S. Department of Energy by Battelle under Contract DE-AC06-67RLO1830. NR 0 TC 0 Z9 0 U1 2 U2 2 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 0039-2103 J9 STRAIN JI Strain PD NOV PY 2000 VL 36 IS 4 BP 165 EP 167 DI 10.1111/j.1475-1305.2000.tb01200.x PG 3 WC Materials Science, Characterization & Testing SC Materials Science GA V22DO UT WOS:000208256100003 ER PT J AU Kedzierski, J Xuan, PQ Subramanian, V Bokor, J King, TJ Hu, CM Anderson, E AF Kedzierski, J Xuan, PQ Subramanian, V Bokor, J King, TJ Hu, CM Anderson, E TI A 20 nm gate-length ultra-thin body p-MOSFET with silicide source/drain SO SUPERLATTICES AND MICROSTRUCTURES LA English DT Article; Proceedings Paper CT 5th Silicon Nanoelectronics Workshop CY JUN 11-12, 2000 CL HONOLULU, HAWAII SP Inst Elect & Electr Engineers DE ultra-thin body; thin-body; silicide source/drain; Schottky source/drain; nanotransistor; fully depleted SOI; SOI MOSFET; scaled CMOS; MOS devices AB As the scaling of CMOS transistors extends to the sub-20 nm regime, the most challenging aspect of device design is the control of the off-state current. The traditional methods for controlling leakage current via the substrate doping profile will be difficult to implement at these dimensions. A promising method for controlling leakage in sub-20 nm transistors is the reduction in source-to-drain leakage paths through the use of a body region which is significantly thinner then the Sate length, with either a single or a double gate. In this paper we present ultra-thin body PMOS transistors with gate lengths down to 20 nm fabricated using a low-barrier silicide as the source and drain. Calixarene-based electron-beam lithography was used to define critical device dimensions. These transistors show 260 muA mum(-1) on-current and on/off current ratios of 10(6), for a conservative oxide thickness of 40 Angstrom and \V-g - V-t\ = 1.2 V. Excellent short-channel effect, with only 0.2 V reduction in \V-t\ is obtained in devices with gate lengths ranging from 100 to 20 nm. (C) 2000 Academic Press. C1 Univ Calif Berkeley, Dept Elect Engn & Comp Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Kedzierski, J (reprint author), Univ Calif Berkeley, Dept Elect Engn & Comp Sci, Berkeley, CA 94720 USA. RI Bokor, Jeffrey/A-2683-2011; Subramanian, Vivek/K-9818-2016 OI Subramanian, Vivek/0000-0002-1783-8219 NR 12 TC 18 Z9 18 U1 0 U2 7 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0749-6036 J9 SUPERLATTICE MICROST JI Superlattices Microstruct. PD NOV-DEC PY 2000 VL 28 IS 5-6 BP 445 EP 452 DI 10.1006/spmi.2000.0947 PG 8 WC Physics, Condensed Matter SC Physics GA 384AT UT WOS:000165917400019 ER PT J AU Baer, DR Engelhard, MH AF Baer, DR Engelhard, MH TI Approach for determining area selectivity in small-area XPS analysis SO SURFACE AND INTERFACE ANALYSIS LA English DT Article DE XPS; analysis area; beam size ID IMAGING PROPERTIES; ANALYZER AB This paper demonstrates that measurements on well-defined 'dots' of a material on a substrate provide a useful experimental approach for determining the area of a specimen that contributes to a small-area XPS measurement. The method provides information that can verify instrument operation conditions and the adequacy of specimen alignment procedures. A data set collected on one system demonstrates how some general properties of an instrument can be learned in order to understand and optimize data collection methods. The relationship of common methods of measuring spatial resolution and the dot test method are discussed. Copyright (C) 2000 John Wiley & Sons, Ltd. C1 Pacific NW Natl Lab, William R Wiley Environm Mol Sci Lab, Richland, WA 99352 USA. RP Baer, DR (reprint author), Pacific NW Natl Lab, William R Wiley Environm Mol Sci Lab, 3335 Q Ave,Box 999,MS K8-93, 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 9 TC 11 Z9 11 U1 0 U2 4 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 NOV PY 2000 VL 29 IS 11 BP 766 EP 772 DI 10.1002/1096-9918(200011)29:11<766::AID-SIA927>3.3.CO;2-P PG 7 WC Chemistry, Physical SC Chemistry GA 376VB UT WOS:000165476500007 ER PT J AU Leyens, C Pint, BA Wright, IG AF Leyens, C Pint, BA Wright, IG TI Effect of composition on the oxidation and hot corrosion resistance of NiAl doped with precious metals SO SURFACE & COATINGS TECHNOLOGY LA English DT Article; Proceedings Paper CT 27th International Conference on Metallurgical Coatings and Thin Films CY APR 10-14, 2000 CL SAN DIEGO, CA SP Amer Vacuum Soc, Adv Surface Engn Div DE nickel aluminides; hot corrosion; oxidation; precious metals ID COATINGS; BEHAVIOR; ALLOYS AB Cast NiAl alloyed with Cr, Pt, Pd, Ir and Ru was tested in l-h cycles at 950 degreesC under hot corrosion conditions and at 1150 degreesC in oxygen. For comparison, Hf-doped NiAl variants and a cast NiPtAl alloy resembling the composition of commercial aluminide coatings were included. Cr was the only element that reduced hot corrosion attack of NiAl significantly. However, at higher temperatures, addition of Cr to Hf-doped NiAl accelerated the alumina scale growth rate and promoted spallation of the oxide scale. The results from initial detailed characterization indicate that rejection of chromium at the metal-oxide interface gives rise to the formation of chromium-rich precipitates in the alloy, which apparently modify its oxidation behavior. This suggests that for NiAl-based substrates, hot corrosion resistance and exceptional scale spallation resistance may be mutually incompatible goals. (C) 2000 Elsevier Science B.V. All rights reserved. C1 DLR, German Aerosp Ctr, Mat Res Inst, D-51170 Cologne, Germany. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Leyens, C (reprint author), DLR, German Aerosp Ctr, Mat Res Inst, D-51170 Cologne, Germany. EM christoph.leyens@dlr.de RI Pint, Bruce/A-8435-2008 OI Pint, Bruce/0000-0002-9165-3335 NR 19 TC 76 Z9 79 U1 6 U2 43 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0257-8972 J9 SURF COAT TECH JI Surf. Coat. Technol. PD NOV PY 2000 VL 133 BP 15 EP 22 DI 10.1016/S0257-8972(00)00878-1 PG 8 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 383MX UT WOS:000165887500004 ER PT J AU Sanders, DM Anders, A AF Sanders, DM Anders, A TI Review of cathodic arc deposition technology at the start of the new millennium SO SURFACE & COATINGS TECHNOLOGY LA English DT Article; Proceedings Paper CT 27th International Conference on Metallurgical Coatings and Thin Films CY APR 10-14, 2000 CL SAN DIEGO, CA SP Amer Vacuum Soc, Adv Surface Engn Div DE vacuum arcs; cathodic arcs; arc plasma deposition; macroparticle filtering; review ID AMORPHOUS-CARBON FILMS; DIAMOND-LIKE CARBON; PULSED VACUUM-ARC; HIGH-ASPECT-RATIO; CHARGE-STATE DISTRIBUTIONS; THIN-FILMS; MECHANICAL-PROPERTIES; SURFACE MODIFICATION; SUBPLANTATION MODEL; ELECTRON-EMISSION AB The vacuum cathodic are has been known as a means of producing coatings since the second half of the 19th century. This makes it one of the oldest known vacuum coating techniques. In the last century it has been recognized that the copious quantities of ions produced by the process provides certain coating property advantages. Specifically, ions can be steered and/or accelerated toward the parts to be coated. This, in turn, can provide enhanced adhesion, film density, and composition stoichiometry in the case of compound coatings. The ions generated by the cathodic are have high 'natural' kinetic energy values in the range 20-200 eV, leading to enhanced surface mobility during the deposition process and even ion subplantation. In many cases, dense coatings are achieved even when the ions arrive at non-normal angles. The ion energy can be further manipulated by the plasma immersion biasing technique. Macroparticle contamination has been alleviated by a variety of novel plasma filters. The purpose of this review is to describe recent developments in macroparticle filtering and are control. These developments promise to broaden the range of applications to the semiconductor, data storage, and optical coatings industry. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Univ Calif Berkeley, Lawrence Berkeley Lab, 1 Cyclotron Rd,MS 53, Berkeley, CA 94720 USA. EM aanders@lbl.gov RI Anders, Andre/B-8580-2009 OI Anders, Andre/0000-0002-5313-6505 NR 120 TC 112 Z9 118 U1 3 U2 29 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0257-8972 J9 SURF COAT TECH JI Surf. Coat. Technol. PD NOV PY 2000 VL 133 BP 78 EP 90 DI 10.1016/S0257-8972(00)00879-3 PG 13 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 383MX UT WOS:000165887500013 ER PT J AU Anders, A MacGill, RA AF Anders, A MacGill, RA TI Twist filter for the removal of macroparticles from cathodic arc plasmas SO SURFACE & COATINGS TECHNOLOGY LA English DT Article; Proceedings Paper CT 27th International Conference on Metallurgical Coatings and Thin Films CY APR 10-14, 2000 CL SAN DIEGO, CALIFORNIA SP Amer Vacuum Soc, Adv Surface Engn Div DE cathodic arc; plasma filter; macroparticles; amorphous carbon films ID VACUUM-ARC; TRANSPORT; COATINGS AB Cathodic are plasmas are known to be contaminated with macroparticles. A variety of magnetic plasma filters have been used with various success in removing the macroparticles from the plasma. In this publication, an open-architecture, double-bent filter that is twisted ('Twist Filter(TM)) is described. A cathodic are plasma deposition system was designed around this novel, very compact and efficient filter. Its major application is the deposition of ultrathin amorphous hard carbon (a-C) films for the magnetic storage industry. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Anders, A (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, 1 Cyclotron Rd,Mailstop 53, Berkeley, CA 94720 USA. RI Anders, Andre/B-8580-2009 OI Anders, Andre/0000-0002-5313-6505 NR 16 TC 31 Z9 32 U1 0 U2 4 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0257-8972 J9 SURF COAT TECH JI Surf. Coat. Technol. PD NOV PY 2000 VL 133 BP 96 EP 100 DI 10.1016/S0257-8972(00)00881-1 PG 5 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 383MX UT WOS:000165887500015 ER PT J AU Perry, AJ Bull, SJ Dommann, A Rafaja, D Wood, BP Michler, M AF Perry, AJ Bull, SJ Dommann, A Rafaja, D Wood, BP Michler, M TI The surface damage in titanium nitride associated with lateral sputtering by argon cluster ions SO SURFACE & COATINGS TECHNOLOGY LA English DT Article; Proceedings Paper CT 27th International Conference on Metallurgical Coatings and Thin Films CY APR 10-14, 2000 CL SAN DIEGO, CA SP Amer Vacuum Soc, Adv Surface Engn Div DE surface smoothing; gas cluster ion bombardment; argon clusters; sputtering ID RESIDUAL-STRESS; DIAMOND FILMS; BEAMS; IMPLANTATION; AR; BOMBARDMENT; DEPOSITION; SIMULATION; LEVEL; TIN AB The surface smoothing of TiN coatings, deposited by CVD or PVD methods, by argon ion clusters comprising some 2000 atoms and carrying only a single positive charge has been confirmed. In addition, the present work has shown that there was no change in the mechanical condition, nanohardness or residual stress, of the PVD coatings. In contrast, the nanohardness in the near-surface region of the CVD TiN coating was increased but, remarkably, there was no concomitant increase in residual stress. A comparison was made with the established effects of ion implantation on the near-surface properties of TiN where a high compressive residual stress is developed if the ion energy lies beyond a threshold value. It was concluded that the vast majority of argon atoms from the clusters move sideways on impacting the sample surface, leading to the well-known lateral sputtering effects associated with the technology, and causing limited surface damage. (C) 2000 Elsevier Science B.V. All rights reserved. C1 AIMS Mkt, San Diego, CA 92127 USA. Univ Newcastle, Div Mat, Newcastle Upon Tyne TW20 0EX, Tyne & Wear, England. Intstate Univ Appl Sci, Inst Mikrosyst Tech, CH-9470 Buchs SG, Switzerland. Charles Univ Prague, Dept Semicond Phys, Prague 12116 2, Czech Republic. Los Alamos Natl Lab, Plasma Phys Grp, Los Alamos, NM 87545 USA. RP Perry, AJ (reprint author), AIMS Consulting, Frohlweg 16, CH-9470 Buchs SG, Switzerland. RI Bull, Stephen/A-5649-2008; Alex, Dommann/K-4583-2013 NR 36 TC 6 Z9 6 U1 1 U2 4 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0257-8972 J9 SURF COAT TECH JI Surf. Coat. Technol. PD NOV PY 2000 VL 133 BP 253 EP 258 DI 10.1016/S0257-8972(00)00931-2 PG 6 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 383MX UT WOS:000165887500040 ER PT J AU Perez, FJ Pedraza, F Hierro, MP Hou, PY AF Perez, FJ Pedraza, F Hierro, MP Hou, PY TI Adhesion properties of aluminide coatings deposited via CVD in fluidised bed reactors (CVD-FBR) on AISI 304 stainless steel SO SURFACE & COATINGS TECHNOLOGY LA English DT Article; Proceedings Paper CT 27th International Conference on Metallurgical Coatings and Thin Films CY APR 10-14, 2000 CL SAN DIEGO, CALIFORNIA SP Amer Vacuum Soc, Adv Surface Engn Div DE CVD-FBR; aluminide coatings ID OXIDATION RESISTANCE; DIFFUSION COATINGS; MICROSTRUCTURE; SUPERALLOYS; ENERGY; CR AB Aluminide coatings are widely used to protect a vast variety of metals and alloys for high temperature applications. Under certain environments, these are not only designed to improve high temperature corrosion, but also erosion. Therefore, the mechanical properties (such as toughness) of these protective coatings obtained by CVD-FBR are of prime importance taking into account the advantages of this coating technique. In this paper, preliminary studies of mechanical characterisation of aluminide coatings obtained on AISI 304 stainless steel by CVD-FBR deposited at 525 degreesC and different processing times are presented. The effect of a subsequent thermal treatment of the aluminide coatings has also been investigated. From the results, the relationship between coating process, heat treatment, and toughness is established. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Complutense Madrid, Dept Ciencia Mat & Ingn Met, E-28040 Madrid, Spain. Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Perez, FJ (reprint author), Univ Complutense Madrid, Dept Ciencia Mat & Ingn Met, E-28040 Madrid, Spain. NR 27 TC 12 Z9 16 U1 1 U2 3 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0257-8972 J9 SURF COAT TECH JI Surf. Coat. Technol. PD NOV PY 2000 VL 133 BP 338 EP 343 DI 10.1016/S0257-8972(00)00952-X PG 6 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 383MX UT WOS:000165887500053 ER PT J AU Matson, DW McClanahan, ED Rice, JP Lee, SL Windover, D AF Matson, DW McClanahan, ED Rice, JP Lee, SL Windover, D TI Effect of sputtering parameters on Ta coatings for gun bore applications SO SURFACE & COATINGS TECHNOLOGY LA English DT Article; Proceedings Paper CT 27th International Conference on Metallurgical Coatings and Thin Films CY APR 10-14, 2000 CL SAN DIEGO, CALIFORNIA SP Amer Vacuum Soc, Adv Surface Engn Div DE high rate sputtering; triode sputtering; tantalum; phase; sputtering gas; temperature ID FILMS AB Tantalum offers a number of attractive properties for gun bore coating applications, including a high melting temperature, high ductility, and an environmentally friendly deposition method. However, vapor-deposited tantalum can appear in both the characteristic bcc phase found in the bulk material, and in a very brittle and less desirable 'beta' phase. Presence of the beta phase in bore coatings is considered undesirable because of its brittleness and resulting failure as the coating is stressed. A high-rate triode sputtering system with a cylindrical coating geometry was used to produce thick tantalum coatings on 4340 steel smooth bore cylindrical substrates. A systematic series of tests were performed to evaluate the effects of sputtering gas species (Ar, Kr, Xe) and substrate temperature (100-300 degreesC) during deposition on the phase and microstructure of the coatings. Heavier sputtering gases and higher substrate temperatures were found to promote the formation of bcc-phase tantalum coatings. Use of a movable target assembly was shown to promote the production of dense, single-phase tantalum coatings. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. ARDEC Benet Labs, Watervliet, NY 12189 USA. RP Matson, DW (reprint author), Pacific NW Natl Lab, POB 999, Richland, WA 99352 USA. NR 19 TC 35 Z9 42 U1 3 U2 13 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0257-8972 J9 SURF COAT TECH JI Surf. Coat. Technol. PD NOV PY 2000 VL 133 BP 411 EP 416 DI 10.1016/S0257-8972(00)00967-1 PG 6 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 383MX UT WOS:000165887500063 ER PT J AU Erdemir, A Eryilmaz, OL Nilufer, IB Fenske, GR AF Erdemir, A Eryilmaz, OL Nilufer, IB Fenske, GR TI Synthesis of superlow-friction carbon films from highly hydrogenated methane plasmas SO SURFACE & COATINGS TECHNOLOGY LA English DT Article; Proceedings Paper CT 27th International Conference on Metallurgical Coatings and Thin Films CY APR 10-14, 2000 CL SAN DIEGO, CALIFORNIA SP Amer Vacuum Soc, Adv Surface Engn Div DE DLC; highly hydrogenated plasmas; superlow friction and wear ID DIAMOND-LIKE CARBON; TRIBOLOGICAL PROPERTIES; AMORPHOUS-CARBON; COATINGS; WEAR; PERFORMANCE AB In this study, we investigated the friction and wear performance of diamond-like carbon films (DLC) derived from increasingly hydrogenated methane plasmas. The films were deposited on steel substrates by a plasma-enhanced chemical vapor deposition process at room temperature and the tribological tests were performed in dry nitrogen. Tests results revealed a close correlation between the hydrogen in the source gas plasma and the friction and wear coefficients of the DLC films. Specifically, films grown in plasmas with higher hydrogen-to-carbon ratios had much lower friction coefficients and wear rates than did films derived from source gases with lower hydrogen-to-carbon ratios. The lowest friction coefficient (0.003) was achieved with a film derived from 25% methane, 75% hydrogen, while a relatively high coefficient of 0.015 was found for films derived from pure methane. Similar correlations were observed for wear rates. Films derived from hydrogen-rich plasmas had the least wear, while films derived from pure methane suffered the highest wear. We used a combination of surface analytical methods to characterize the structure and chemistry of the DLC films and worn surfaces. (C) 2000 Published by Elsevier Science B.V. All rights reserved. C1 Argonne Natl Lab, Div Energy Technol, Argonne, IL 60439 USA. Istanbul Tech Univ, Dept Mat & Met Engn, TR-80626 Istanbul, Turkey. RP Erdemir, A (reprint author), Argonne Natl Lab, Div Energy Technol, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 36 TC 109 Z9 114 U1 2 U2 25 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0257-8972 J9 SURF COAT TECH JI Surf. Coat. Technol. PD NOV PY 2000 VL 133 BP 448 EP 454 DI 10.1016/S0257-8972(00)00968-3 PG 7 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 383MX UT WOS:000165887500069 ER PT J AU Jankowski, A McKernan, M Chesser, J AF Jankowski, A McKernan, M Chesser, J TI The use of magnetron arrays for depositing large-area oxide coatings SO SURFACE & COATINGS TECHNOLOGY LA English DT Article; Proceedings Paper CT 27th International Conference on Metallurgical Coatings and Thin Films CY APR 10-14, 2000 CL SAN DIEGO, CALIFORNIA SP Amer Vacuum Soc, Adv Surface Engn Div DE large area deposition; sputter deposition; metal-oxide coatings; linear arrays AB The application of coatings over large areas can be approached through the use of large deposition sources. A versatile alternative, e.g. to long rectangular magnetrons, are linear arrays of circular planar magnetrons to process coatings over wide path lengths. We investigate the feasibility of using a linear array of 76-mm-diameter magnetron sources operated in the rf mode to deposit oxide target materials across a path in excess of 0.7 m wide. Specific results are given for the case of a 2-mum-thick alumina coating. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Jankowski, A (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808, Livermore, CA 94551 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0257-8972 J9 SURF COAT TECH JI Surf. Coat. Technol. PD NOV PY 2000 VL 133 BP 602 EP 605 DI 10.1016/S0257-8972(00)00903-8 PG 4 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 383MX UT WOS:000165887500093 ER PT J AU Alfonso, DR Jaffe, JE Hess, AC Gutowski, M AF Alfonso, DR Jaffe, JE Hess, AC Gutowski, M TI High-coverage adsorption of alkali metals at the CaO and MgO (100) surfaces SO SURFACE SCIENCE LA English DT Article DE adsorption kinetics; alkali metals; density functional theory calculations ID GENERALIZED GRADIENT APPROXIMATION; ELECTRONIC-STRUCTURE; OXIDE SURFACES; NA; MGO(100); FILMS; CHEMISORPTION; MOLECULES; DENSITY; SITES AB The interaction of alkali metals (Li and Na) with the defect-free (100) surface of CaO and MgO has been studied in the framework of density functional theory with periodic boundary conditions for the coverages 1.0 and 0.5 ML (Li) and 0.5 ML (Na). The lateral interaction among adsorbed alkali atoms contributes significantly to the stabilization of the metallic layer. The binding energy of Li for the 1.0 ML coverage is comparable for CaO and MgO and is larger than the cohesive energy of bulk Li. Hence, this monolayer is stable with respect to formation of a three-dimensional metallic island, and a small lattice mismatch between MgO(100) and the bcc Li indicates the possibility of creating a low-energy interface between these two materials under proper growth conditions. The chemical effects in the metal-substrate interaction are not significant. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Pacific NW Natl Lab, Div Energy, Richland, WA 99352 USA. Univ Gdansk, Dept Chem, PL-80952 Gdansk, Poland. RP Gutowski, M (reprint author), Pacific NW Natl Lab, Div Energy, Richland, WA 99352 USA. NR 37 TC 15 Z9 15 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 J9 SURF SCI JI Surf. Sci. PD NOV 1 PY 2000 VL 466 IS 1-3 BP 111 EP 118 DI 10.1016/S0039-6028(00)00737-8 PG 8 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA 374AQ UT WOS:000165322600015 ER PT J AU Yakimov, AV Savvate'ev, VN Davidov, D AF Yakimov, AV Savvate'ev, VN Davidov, D TI The role of traps in polymer-based light-emitting devices SO SYNTHETIC METALS LA English DT Article; Proceedings Paper CT Spring Meeting of the European-Materials-Research-Society CY JUN 01-04, 1999 CL STRASBOURG, FRANCE SP European Mat Res Soc DE electroluminescence; charge injection; traps; poly-phenylene vinylene and derivatives; light sources ID ELECTROLUMINESCENT DEVICES; LIMITED CONDUCTION; DIODES; VINYLENE) AB We describe 'injectionless' electroluminescence (EL) mechanism in organic light-emitting diodes (LED) based on 'thick' films of poly(phenylene vinylene) (PPV) and poly-[2-methuxy-5-(2-ethylhexoxy)-1,4-phenylene vinylene] (MEH-PPV) sandwiched between ITO and Al electrodes. We provide evidence that this mechanism is associated with detrapping of charge carriers from 'shallow' traps. A pump-probe experiment allows an estimate of the trapping-detrapping time scale. This time scale suggests the location of trap levels at 0.15 eV above the HOMO band. We also demonstrate spatially-resolved EL enhancement in thin him devices that can he achieved by simultaneous illumination and biasing the device. We attribute the EL enhancement to charging of traps located near Al/polymer interface. Slow temporal decay of the EL enhancement corresponds to charge release process from 'deep' (0.8 eV) traps. (C) 2000 Elsevier Science S.A. All rights reserved. C1 Hebrew Univ Jerusalem, Racah Inst Phys, IL-91904 Jerusalem, Israel. Iowa State Univ, Dept Phys & Astron, US DOE, Ames Lab, Ames, IA 50011 USA. RP Yakimov, AV (reprint author), Hebrew Univ Jerusalem, Racah Inst Phys, IL-91904 Jerusalem, Israel. NR 19 TC 15 Z9 15 U1 0 U2 3 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0379-6779 J9 SYNTHETIC MET JI Synth. Met. PD NOV 1 PY 2000 VL 115 IS 1-3 BP 51 EP 56 DI 10.1016/S0379-6779(00)00300-3 PG 6 WC Materials Science, Multidisciplinary; Physics, Condensed Matter; Polymer Science SC Materials Science; Physics; Polymer Science GA 366FP UT WOS:000089994400011 ER PT J AU Poet, TS AF Poet, TS TI Assessing dermal absorption SO TOXICOLOGICAL SCIENCES LA English DT Editorial Material ID HUMANS C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Poet, TS (reprint author), Pacific NW Natl Lab, POB 999, Richland, WA 99352 USA. NR 7 TC 17 Z9 17 U1 0 U2 0 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 1096-6080 J9 TOXICOL SCI JI Toxicol. Sci. PD NOV PY 2000 VL 58 IS 1 BP 1 EP 2 DI 10.1093/toxsci/58.1.1 PG 2 WC Toxicology SC Toxicology GA 368MZ UT WOS:000090122500002 PM 11053533 ER PT J AU Gourley, PL Gourley, MF AF Gourley, PL Gourley, MF TI Biocavity lasers for biomedicine SO TRENDS IN BIOTECHNOLOGY LA English DT Article ID SEMICONDUCTOR; SPECTROSCOPY; TISSUE AB Laser technology has advanced dramatically and is an integral part of the healthcare delivery systems of today. Lasers are used in laboratory analyses of human blood samples and serve as surgical tools that kill, burn or cut tissue. Recent semiconductor microtechnology has reduced the laser size to the size of a biological cell or even a virus particle. The integration of these ultra-small lasers with biological systems makes it possible to create microelectrical mechanical systems that might revolutionize healthcare delivery. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Washington Hosp Ctr, Washington, DC 20010 USA. RP Gourley, PL (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 22 TC 3 Z9 3 U1 0 U2 2 PU ELSEVIER SCIENCE LONDON PI LONDON PA 84 THEOBALDS RD, LONDON WC1X 8RR, ENGLAND SN 0167-7799 J9 TRENDS BIOTECHNOL JI Trends Biotechnol. PD NOV PY 2000 VL 18 IS 11 BP 443 EP 448 DI 10.1016/S0167-7799(00)01496-7 PG 6 WC Biotechnology & Applied Microbiology SC Biotechnology & Applied Microbiology GA 373BE UT WOS:000165267900003 PM 11058784 ER PT J AU Glass, RJ Conrad, SH Peplinski, W AF Glass, RJ Conrad, SH Peplinski, W TI Gravity-destabilized nonwetting phase invasion in macroheterogeneous porous media: Experimental observations of invasion dynamics and scale analysis SO WATER RESOURCES RESEARCH LA English DT Article ID WETTING FRONT INSTABILITY; PERCOLATION MODEL; LIQUIDS; DISSOLUTION; MIGRATION; BEHAVIOR; SYSTEMS; DNAPL AB We designed and conducted experiments in a heterogeneous sand pack where gravity-destabilized nonwetting phase invasion (CO2 and trichloroethylene) could be recorded using high-resolution light transmission methods. The heterogeneity structure was designed to be reminiscent of fluvial channel lag cut-and-fill architecture and to contain a series of capillary barriers. As invasion progressed, nonwetting phase structure developed a series of fingers and pools; behind the growing front we found nonwetting phase saturation to pulsate in certain regions when viscous forces were low. Through a scale analysis we derive a series of length scales that describe finger diameter, pool height and width, and regions where pulsation occurs within a heterogeneous porous medium. In all cases we find that the intrinsic pore-scale nature of the invasion process and resulting structure must be incorporated into our analysis to explain experimental results. We propose a simple macroscale structural growth model that assembles length scales for substructures to delineate nonwetting phase migration from a source into a heterogeneous domain. For such a model applied at the field scale for dense nonaqueous phase liquid migration, we expect capillary and gravity forces within the complex subsurface lithology to play the primary roles with viscous forces forming a perturbation on the inviscid phase structure. C1 Sandia Natl Labs, Floor Visualizat & Proc Lab, Albuquerque, NM 87185 USA. RP Glass, RJ (reprint author), Sandia Natl Labs, Floor Visualizat & Proc Lab, POB 5800, Albuquerque, NM 87185 USA. NR 34 TC 65 Z9 65 U1 1 U2 18 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 NOV PY 2000 VL 36 IS 11 BP 3121 EP 3137 DI 10.1029/2000WR900152 PG 17 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA 368YY UT WOS:000090146100001 ER PT J AU Knapp, RB Chiarappa, ML Durham, WB AF Knapp, RB Chiarappa, ML Durham, WB TI An experimental exploration of the transport and capture of abiotic colloids in a single fracture SO WATER RESOURCES RESEARCH LA English DT Article ID METHYLOSINUS-TRICHOSPORIUM OB3B; POROUS-MEDIA; BACTERIAL TRANSPORT; SURFACE-ROUGHNESS; FLUID-FLOW; ROCK; MODEL; SUSPENSIONS; FILTRATION; INJECTION AB The effect of microscale surface roughness in fracture walls is shown to accelerate colloid transport relative to a tracer and to increase colloid capture. These results are from experiments on duplicate laboratory experiments using synthetic, neutrally buoyant, abiotic, colloidal particles and two dense rhyolitic tuff cores. One core has a single, rough-walled fracture with an average aperture of 450 mum. We have used a profilometer to measure the fracture topography and calculate aperture distributions and surface areas in the reconstructed core. The other core has a smooth, channelized slit that is a parallel-plate analogue to the fractured core. Identical tracer and particle pulses were injected into each core. Particle capture by electrostatic attachment in the parallel-plate core gives a retention capacity of 55 x 10(9) particles m(-2). In the rough-walled fracture core, average particle transport rates are a full fracture volume faster than average tracer transport rates. Reynolds flow simulation indicates the presence of highly channelized fluid flow that likely contributes to this accelerated particle transport. Capture in the fractured core was 90 x 10(9) particles m(-2) retention capacity is unknown because particle concentrations in the effluent achieved a steady state value of only 85% of the injected concentration. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Knapp, RB (reprint author), Lawrence Livermore Natl Lab, 7000 East Ave, Livermore, CA 94550 USA. EM knapp4@llnl.gov NR 70 TC 17 Z9 18 U1 0 U2 4 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 NOV PY 2000 VL 36 IS 11 BP 3139 EP 3149 DI 10.1029/2000WR900145 PG 11 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA 368YY UT WOS:000090146100002 ER PT J AU Saiers, JE Guha, H Jardine, P Brooks, S AF Saiers, JE Guha, H Jardine, P Brooks, S TI Development and evaluation of a mathematical model for the transport and oxidation-reduction of CoEDTA SO WATER RESOURCES RESEARCH LA English DT Article ID CO(II/III)EDTA REACTIVE TRANSPORT; POROUS-MEDIA; CHROMIUM(III) OXIDATION; MANGANESE-DIOXIDE; EDTA COMPLEXES; ADSORPTION; IRON; KINETICS; COBALT; OXIDES AB Oxidation-reduction reactions influence the subsurface mobility of a wide variety of toxic contaminants. In the work reported here, we develop a new model for coupled transport and oxidation-reduction, and we test the model against published data on the movement of CoEDTA (cobalt ethylenediaminetetraacetic acid) through columns packed with beta -MnO2-coated sand. The model solves equations for the advective-dispersive transport of three aqueous species: Co(II)EDTA, Co(III)EDTA, and dissolved oxygen. These transport equations are linked with nonlinear kinetics expressions that describe (1) oxidation of Co(II)EDTA to Co(III)EDTA by beta -MnO2, (2) inhibition of Co(II)EDTA oxidation due to precipitation of Mn2O3, an insoluble reaction product that occludes the beta -MnO2 surface, and (3) regeneration of the redox-reactive beta -MnO2 surface through oxidation of the Mn2O3 precipitate by dissolved oxygen. Comparison of experimental and calculated results demonstrates that the model describes the response of the coupled hydrological and geochemical processes to changes in flow rate, influent concentrations of Co(II)EDTA, and beta -MnO2 surface coverages. C1 Yale Univ, Sch Environm Studies, New Haven, CT 06511 USA. Florida Int Univ, Dept Geol, Miami, FL 33199 USA. Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. RP Saiers, JE (reprint author), Yale Univ, Sch Environm Studies, 370 Prospect St, New Haven, CT 06511 USA. NR 38 TC 15 Z9 16 U1 0 U2 6 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 NOV PY 2000 VL 36 IS 11 BP 3151 EP 3165 DI 10.1029/2000WR900210 PG 15 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA 368YY UT WOS:000090146100003 ER PT J AU Chantler, CT Tran, CQ Paterson, D Barnea, Z Cookson, DJ AF Chantler, CT Tran, CQ Paterson, D Barnea, Z Cookson, DJ TI Monitoring fluctuations at a synchrotron beamline using matched ion chambers: 1. modelling, data collection, and deduction of simple measures of association SO X-RAY SPECTROMETRY LA English DT Article ID EXAFS MEASUREMENTS; ABSORPTION; PHYSICS AB The Bur, brightness and temporal characteristics of an x-ray source often define its utility for a specific experiment. However, there are numerous contributions to the statistics of a beam as observed by a particular detector and associated electronics. The significance of these fluctuations is often neglected, with a consequent loss of precision or accuracy of up to two orders of magnitude. An understanding of the detected statistics for a given arrangement (and the means for optimizing this) can make the difference between a successful experiment and a much more limited investigation. We explain the method for measuring a wide variety of important statistical contributions to high accuracy, and draw attention to the statistical consequences of optimized monitoring of upstream signals, We discuss the use of two matched ion chambers on a monochromatized bending magnet beam at the Photon Factory, Tsukuba, Japan. This is an illustration of a general principle, also applicable to conventional fixed x-ray sources, for investigating simple measures of association, It allows the quantification of uncertainties of spectrometric measurements, and also allows these to be minimized. Copyright (C) 2000 John Wiley & Sons, Ltd. C1 Univ Melbourne, Sch Phys, Parkville, Vic 3010, Australia. Australian Nucl Sci & Technol Org, Menai, NSW 2234, Australia. Argonne Natl Lab, CAT, CARS,MAT, Chem, Argonne, IL 60439 USA. RP Chantler, CT (reprint author), Univ Melbourne, Sch Phys, Parkville, Vic 3010, Australia. RI Chantler, Christopher/D-4744-2013; Tran, Chanh/M-7868-2015 OI Chantler, Christopher/0000-0001-6608-0048; NR 17 TC 19 Z9 19 U1 0 U2 1 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 0049-8246 J9 X-RAY SPECTROM JI X-Ray Spectrom. PD NOV-DEC PY 2000 VL 29 IS 6 BP 449 EP 458 DI 10.1002/1097-4539(200011/12)29:6<449::AID-XRS452>3.0.CO;2-R PG 10 WC Spectroscopy SC Spectroscopy GA 377QA UT WOS:000165523400010 ER PT J AU Chantler, CT Tran, CQ Paterson, D Cookson, DJ Barnea, Z AF Chantler, CT Tran, CQ Paterson, D Cookson, DJ Barnea, Z TI Monitoring fluctuations at a synchrotron beamline using matched ion chambers: 2. isolation of component noise sources, and application to attenuation measurements showing increased precision by two orders of magnitude SO X-RAY SPECTROMETRY LA English DT Article ID RAY AB The significance of statistical fluctuations in a synchrotron beam is often neglected, with a consequent loss of precision or accuracy of up to two orders of magnitude. We illustrate this for the specific example of an x-ray attenuation measurement, Since all x-ray measurements involve either scattering or absorption (or both), the net potential gain in precision is similar for all such experiments, including crystallographic and XAFS determinations. We demonstrate the net gain with data obtained with two matched ion chambers on a monochromatized bending magnet beam at the Photon Factory, Tsukuba, Japan. Isolating and measuring component contributions to the overall fluctuations allows a robust determination of the limiting experimental precision. This approach also determines the absolute incident flux without measuring the absolute photon count. The type of statistical analysis described is not only a post facto diagnostic tool but, by being incorporated into the experiment on-line, can provide a real-time optimizing intervention in the measurement process. Copyright (C) 2000 John Wiley & Sons, Ltd. C1 Univ Melbourne, Sch Phys, Parkville, Vic 3010, Australia. Australian Nucl Sci & Technol Org, Menai, NSW 2234, Australia. Argonne Natl Lab, CAT, CARS, Mat,Chem, Argonne, IL 60439 USA. RP Chantler, CT (reprint author), Univ Melbourne, Sch Phys, Parkville, Vic 3010, Australia. RI Chantler, Christopher/D-4744-2013; Tran, Chanh/M-7868-2015 OI Chantler, Christopher/0000-0001-6608-0048; NR 6 TC 16 Z9 16 U1 0 U2 2 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 0049-8246 J9 X-RAY SPECTROM JI X-Ray Spectrom. PD NOV-DEC PY 2000 VL 29 IS 6 BP 459 EP 466 DI 10.1002/1097-4539(200011/12)29:6<459::AID-XRS453>3.0.CO;2-N PG 8 WC Spectroscopy SC Spectroscopy GA 377QA UT WOS:000165523400011 ER PT J AU Forte, TM Blanche, PJ Subbanagounder, G Berliner, JA Oda, MM Bielicki, JK AF Forte, TM Blanche, PJ Subbanagounder, G Berliner, JA Oda, MM Bielicki, JK TI Response of the anti-atherogenic enzymes lecithin : cholesterol acyltransferase (LCAT), paraoxonase (PON) and platelet-activating acetylhydrolase (PAF-AH) in atherosclerosis susceptible mice SO CIRCULATION LA English DT Meeting Abstract C1 Lawrence Berkeley Natl Lab, Berkeley, CA USA. Univ Calif Los Angeles, Los Angeles, CA USA. Univ Calif Berkeley, Berkeley, CA 94720 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0009-7322 J9 CIRCULATION JI Circulation PD OCT 31 PY 2000 VL 102 IS 18 SU S MA 399 BP 83 EP 83 PG 1 WC Cardiac & Cardiovascular Systems; Peripheral Vascular Disease SC Cardiovascular System & Cardiology GA 367QE UT WOS:000090072300398 ER PT J AU Oda, MN Bielicki, JK Ho, TT Rubin, EM Forte, TM AF Oda, MN Bielicki, JK Ho, TT Rubin, EM Forte, TM TI Over-expression of paraoxonase (PON) in mice confers resistance against oxidative inhibition of lecithin : cholesterol acyltransferase (LCAT). SO CIRCULATION LA English DT Meeting Abstract C1 Lawrence Berkeley Natl Lab, Berkeley, CA USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0009-7322 J9 CIRCULATION JI Circulation PD OCT 31 PY 2000 VL 102 IS 18 SU S MA 703 BP 145 EP 145 PG 1 WC Cardiac & Cardiovascular Systems; Peripheral Vascular Disease SC Cardiovascular System & Cardiology GA 367QE UT WOS:000090072300701 ER PT J AU Qiu, Y Cavelier, L Cheng, JF Rubin, EM AF Qiu, Y Cavelier, L Cheng, JF Rubin, EM TI Human and mouse ABCA1 comparative sequencing and transgenesis studies identify regulatory elements SO CIRCULATION LA English DT Meeting Abstract C1 Lawrence Berkeley Natl Lab, Berkeley, CA USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0009-7322 J9 CIRCULATION JI Circulation PD OCT 31 PY 2000 VL 102 IS 18 SU S MA 1522 BP 311 EP 311 PG 1 WC Cardiac & Cardiovascular Systems; Peripheral Vascular Disease SC Cardiovascular System & Cardiology GA 367QE UT WOS:000090072301517 ER PT J AU Hoek, TLV Shao, Z Li, CQ Kasza, KE Jayakar, D Idris, AH Becker, LB AF Hoek, TLV Shao, Z Li, CQ Kasza, KE Jayakar, D Idris, AH Becker, LB TI Do we reperfuse or cool down first to resuscitate ischemic tissue? SO CIRCULATION LA English DT Meeting Abstract C1 Univ Chicago, Chicago, IL 60637 USA. Argonne Natl Lab, Argonne, IL 60439 USA. Univ Florida, Gainesville, FL USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0009-7322 J9 CIRCULATION JI Circulation PD OCT 31 PY 2000 VL 102 IS 18 SU S MA 2765 BP 570 EP 570 PG 1 WC Cardiac & Cardiovascular Systems; Peripheral Vascular Disease SC Cardiovascular System & Cardiology GA 367QE UT WOS:000090072302759 ER PT J AU Becker, LB Kasza, KE Jayakar, D Williams, U Padrid, P Idris, AH Hoek, TLV AF Becker, LB Kasza, KE Jayakar, D Williams, U Padrid, P Idris, AH Hoek, TLV TI Rapid induction of hypothermia using phase-change ice slurry: Targeted cooling of the heart and brain during cardiac arrest SO CIRCULATION LA English DT Meeting Abstract C1 Univ Chicago, Chicago, IL 60637 USA. Argonne Natl Lab, Argonne, IL 60439 USA. Univ Florida, Gainesville, FL USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0009-7322 J9 CIRCULATION JI Circulation PD OCT 31 PY 2000 VL 102 IS 18 SU S MA 2769 BP 571 EP 571 PG 1 WC Cardiac & Cardiovascular Systems; Peripheral Vascular Disease SC Cardiovascular System & Cardiology GA 367QE UT WOS:000090072302763 ER PT J AU Groch, MW Depuey, EG Belzberg, AD Marshall, RC Barnett, CA Kamran, M Nichols, K Spies, SM Erwin, WD AF Groch, MW Depuey, EG Belzberg, AD Marshall, RC Barnett, CA Kamran, M Nichols, K Spies, SM Erwin, WD TI Assessment of left ventricular performance by gated blood pool SPECT: A multicenter study SO CIRCULATION LA English DT Meeting Abstract C1 Northwestern Univ, Chicago, IL 60611 USA. St Lukes Roosevelt Hosp Ctr, New York, NY USA. Univ British Columbia, Vancouver, BC V5Z 1M9, Canada. Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. Univ Calif Davis, Davis, CA 95616 USA. Columbia Univ, New York, NY USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0009-7322 J9 CIRCULATION JI Circulation PD OCT 31 PY 2000 VL 102 IS 18 SU S MA 3508 BP 725 EP 725 PG 1 WC Cardiac & Cardiovascular Systems; Peripheral Vascular Disease SC Cardiovascular System & Cardiology GA 367QE UT WOS:000090072303500 ER PT J AU Melendres, CA Hahn, F Bowmaker, GA AF Melendres, CA Hahn, F Bowmaker, GA TI Oxyanion adsorption and competition at a gold electrode SO ELECTROCHIMICA ACTA LA English DT Article DE far infrared spectroscopy; adsorbed oxyanions; gold electrode; synchrotron source; competitive adsorption ID ENHANCED RAMAN-SPECTROSCOPY; QUARTZ-CRYSTAL MICROBALANCE; FAR-INFRARED SPECTROSCOPY; INSITU FT-IR; SULFURIC-ACID; SULFATE ADSORPTION; AU(111) ELECTRODE; COPPER ELECTRODE; SURFACE; IONS AB Synchrotron Far Infrared Reflectance Spectroscopy (SFIRS) has been used to study the adsorption of oxyanions at a gold thin-film electrode. Surface-adsorbate vibrational frequencies of 240 and 255 cm(-1) have been measured 'in-situ' in acid solutions of 0.5 M HClO4 containing 0.05 M Na2SO4, and Na3PO4, respectively. It was observed that in the presence of Br-, competitive adsorption occurs such that phosphate is displaced from the electrode surface and the current-potential behavior of the electrode is determined by the more strongly adsorbed Br- anion. In 0.1 M NaClO4 at neutral pH, no interaction between the oxyanions and the gold surface could be observed and the intensity of Au-Cl- vibration was about 5 times weaker than in acid. Adsorption of OH was found to be the dominant interaction, inhibiting sulfate adsorption, in 0.05 M Na2SO4 + 0.1 M NaClO4 solution. The latter finding is similar to results obtained by others on the inhibition of sulfate adsorption on Ag by OH-. (C) 2000 Elsevier Science Ireland Ltd. All rights reserved. C1 Argonne Natl Lab, Argonne, IL 60439 USA. Univ Poitiers, CNRS UMR 6503, Equipe Electrocatalyse, F-86022 Poitiers, France. Univ Auckland, Dept Chem, Auckland, New Zealand. RP Melendres, CA (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 23 TC 15 Z9 16 U1 5 U2 12 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0013-4686 J9 ELECTROCHIM ACTA JI Electrochim. Acta PD OCT 31 PY 2000 VL 46 IS 1 BP 9 EP 13 DI 10.1016/S0013-4686(00)00516-8 PG 5 WC Electrochemistry SC Electrochemistry GA 369UA UT WOS:000165084300002 ER PT J AU Harrup, MK Stewart, FF AF Harrup, MK Stewart, FF TI Improved method for the isolation and purification of water-soluble polyphosphazenes SO JOURNAL OF APPLIED POLYMER SCIENCE LA English DT Article DE polymers; phosphazenes; hydrophilic; purification; solubility ID SIDE GROUPS; SOLUBILITY; HYDROGELS; MEMBRANES; POLYMERS AB We report in this article an improved procedure to isolate and purify representative water-soluble polyphosphazenes that dramatically reduces the time and equipment involved, while maintaining or exceeding the yields and purity reported in the literature for these polymers obtained using dialysis methods. This technique takes advantage of the phase transition behavior exhibited by some hydrophilic polymers, namely that associated with the lower critical solubility temperature (LCST). The polymers used in this study were poly[bis-(2-(2-methoxyethoxy)ethoxy)phosphazene], MEEP (1), and two new water-soluble polymers. These polymers are similar to MEEP, yet they contain a small percentage of a crosslinkable pendant group; either 8-hydroxy-ethyl allyl ether (2), or o-allyl phenol (3). The observed behavior was quite different for these two polymers than that found for MEEP, and is a direct consequence of the pendant group substitution patterns. Although the homopolymer MEEP yielded a single sharp LCST point, the two heteropolymers exhibited this phase transition over a broader temperature range. Further, fractionation of polymer 3, based on pendant group speciation, was possible due to the more hydrophobic nature of the phenol. (C) 2000 John Wiley & Sons, Inc. C1 Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. RP Harrup, MK (reprint author), Idaho Natl Engn & Environm Lab, POB 1625, Idaho Falls, ID 83415 USA. NR 13 TC 10 Z9 11 U1 1 U2 2 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0021-8995 J9 J APPL POLYM SCI JI J. Appl. Polym. Sci. PD OCT 31 PY 2000 VL 78 IS 5 BP 1092 EP 1099 DI 10.1002/1097-4628(20001031)78:5<1092::AID-APP180>3.0.CO;2-6 PG 8 WC Polymer Science SC Polymer Science GA 349QG UT WOS:000089056700018 ER PT J AU Jeong, B Kibbey, MR Birnbaum, JC Won, YY Gutowska, A AF Jeong, B Kibbey, MR Birnbaum, JC Won, YY Gutowska, A TI Thermogelling biodegradable polymers with hydrophilic backbones: PEG-g-PLGA SO MACROMOLECULES LA English DT Article ID OXIDE) TRIBLOCK COPOLYMER; AQUEOUS-SOLUTION; DIBLOCK COPOLYMERS; LIGHT-SCATTERING; ETHYLENE-OXIDE; MICELLIZATION; GELATION; THERMODYNAMICS; ASSOCIATION; TEMPERATURE AB The aqueous solutions of poly(ethylene glycol) grafted with poly(lactic acid-co-glycolic acid) flow freely at room temperature but form gels at higher temperature. The existence of micelles in water at low polymer concentration was confirmed by cryo-transmission electron microscopy and dye solubilization studies. The micellar diameter is about 9 nm, and the critical micelle concentration is in a range of 0.01-0.05 wt %. The critical gel concentration, above which a gel phase appears, was 16 wt %, and the sol-to-gel transition temperature was slightly affected by the concentration between 16 and 25 wt %. At sol-to-gel transition, viscosity and modulus increased abruptly, and C-13 NMR showed molecular motion of hydrophilic poly(ethylene glycol) backbones decreased while that of hydrophobic poly(lactic acid-co-glycolic acid) side chains increased. The hydrogel of PEG-g-PLGA with hydrophilic backbones was transparent during degradation and remained a gel for 1 week,suggesting a promising material for shortterm drug delivery. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. Univ Minnesota, Dept Chem Engn & Mat Sci, Minneapolis, MN 55455 USA. RP Gutowska, A (reprint author), Pacific NW Natl Lab, 902 Battelle Blvd,POB 999,K2-44, Richland, WA 99352 USA. NR 30 TC 141 Z9 151 U1 4 U2 36 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0024-9297 J9 MACROMOLECULES JI Macromolecules PD OCT 31 PY 2000 VL 33 IS 22 BP 8317 EP 8322 DI 10.1021/ma000638v PG 6 WC Polymer Science SC Polymer Science GA 370UL UT WOS:000165140700031 ER PT J AU Fornasiero, F Halim, M Prausnitz, JM AF Fornasiero, F Halim, M Prausnitz, JM TI Vapor-sorption equilibria for 4-vinylpyridine-based copolymer and cross-linked polymer/alcohol systems. Effect of "intramolecular repulsion" SO MACROMOLECULES LA English DT Article ID HOLLOW-FIBER MEMBRANES; POLY(STYRENE-B-4-VINYLPYRIDINE) DIBLOCK COPOLYMER; LIQUID-EQUILIBRIA; AQUATIC ENVIRONMENT; ORGANIC POLLUTANTS; POLYMER-SOLUTIONS; PHASE-BEHAVIOR; POLY(2,6-DIMETHYL-1,4-PHENYLENE OXIDE); POLYVINYLPYRIDINE MEMBRANE; METHYL-METHACRYLATE AB Solvent activity data were obtained for three alcohols (methanol, 2-propanol, tert-butyl alcohol) in 4-vinylpyridine (4VP)-based polymers using a classical isothermal gravimetric-sorption method. The polymers were linear poly(4-vinylpyridine) (M-w = 160 000), cross-linked poly(4-vinylpyridine) with 2 and 25 wt % divinylbenzene as cross-linking agent, random copolymers poly(4-vinylpyridine-co-styrene) (P4VP-co-S) (10 and 50 wt % styrene), and block copolymer P4VP-b-S (50 wt % styrene). The temperature range was 55-70 degreesC. Sorption in P4VP-co-10%S copolymer is significantly higher than that in the respective homopolymers. Sorption in P4VP-co-50%S is close to that in linear P4VP, while the sorption curve (solvent activity vs solvent weight fraction) for P4VP-b-50%S lies in between those for the two parent homopolymers. For cross-linked P4VP, the amount of solvent absorbed by the polymers strongly depends on the weight fraction of the cross-linking agent. When solvent activity is plotted as a function of solvent weight fraction for various degrees of cross-linking, there is an unexpected crossover among the curves. At low solvent activity, the largest sorption was for the 25% cross-linked polymer and the lowest for the linear polymer; however, at high solvent activity the curves snitch position, and the linear poly(4-vinylpyridine) absorbs more than the cross-linked poly(4-vinylpyridine). This unusual behavior may be explained by "intramolecular repulsion" between bonded unlike segments (4-vinylpyridine and styrene/divinylbenzene in un-cross-linked/cross-linked copolymers, respectively) and by elastic contributions to the solvent chemical potential in cross-linked P4VP. In block copolymers, segregated sequence of the unlike monomers minimizes the effect of "intramolecular repulsion". C1 Univ Calif Berkeley, Dept Chem Engn, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Chem Sci, Berkeley, CA 94720 USA. RP Prausnitz, JM (reprint author), Univ Calif Berkeley, Dept Chem Engn, Berkeley, CA 94720 USA. RI Fornasiero, Francesco/I-3802-2012 NR 74 TC 7 Z9 7 U1 0 U2 6 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0024-9297 J9 MACROMOLECULES JI Macromolecules PD OCT 31 PY 2000 VL 33 IS 22 BP 8435 EP 8442 DI 10.1021/ma000739t PG 8 WC Polymer Science SC Polymer Science GA 370UL UT WOS:000165140700046 ER PT J AU Zhu, YT Lowe, TC AF Zhu, YT Lowe, TC TI Observations and issues on mechanisms of grain refinement during ECAP process SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article DE grain refinement; equal channel angular pressing; mechanisms ID CHANNEL ANGULAR EXTRUSION; SIMPLE SHEAR; ALUMINUM; MICROSTRUCTURE; TEXTURE; COPPER; BOUNDARIES; TITANIUM; WORKING; TORSION AB The equal channel angular pressing route, defined by rotating schemes between adjacent passes, significantly affects effectiveness of grain refinement. It is of interest to study the mechanisms of grain refinement. Previous work has considered the accumulative strain and the effects of shear strain plane in the interpretation of certain experimental observations. However, they are not sufficiently general, and contradict each other in some cases. In this paper, we analyze experimental results available in the literature, and investigate the fundamental mechanisms of grain refinement. We believe that the interaction of shear plane with texture and crystal structure plays a primary role in grain refinement, while the accumulative strain plays a secondary role. Our model can explain the experimental results in the literature very well. Issues on the grain refinement are discussed and further research to solve these issues is suggested. (C) 2000 Elsevier Science S.A. All rights reserved. C1 Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. RP Zhu, YT (reprint author), Los Alamos Natl Lab, Div Mat Sci & Technol, Mail Stop G755, Los Alamos, NM 87545 USA. EM yzhu@lanl.gov RI Zhu, Yuntian/B-3021-2008 OI Zhu, Yuntian/0000-0002-5961-7422 NR 46 TC 281 Z9 308 U1 7 U2 42 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 OCT 31 PY 2000 VL 291 IS 1-2 BP 46 EP 53 DI 10.1016/S0921-5093(00)00978-3 PG 8 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 352ZK UT WOS:000089249100007 ER PT J AU Romhanji, E Mitlin, D Radmilovic, V AF Romhanji, E Mitlin, D Radmilovic, V TI Deformation pattern and strain hardening in a highly textured 8090 Al-Li alloy sheet SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article DE Al-Li alloy; texture; deformation pattern; slip traces; strain hardening; Taylor orientation factor ID PLASTIC ANISOTROPY; METALS; PLATE AB Structure-deformation pattern analysis was made on a highly textured 8090 AI-Li alloy sheet deformed in tension. It is shown that the sharp beta-fiber type crystallographic texture induces a strong orientation variation in the mechanical properties and in the deformation structure. The soft orientation is 55 degrees in respect to the rolling direction (RD), while the hard orientation is parallel to the RD. Both results are predicted from the detected texture by the relaxed constrained Taylor deformation model (RC). Cellular dislocation substructure was observed in the samples deformed parallel to the RD. However, in the samples tested 55 degrees to the RD, coplanar dislocation arrangement was preserved even up to 30% elongation. In the hard orientation, the strain hardening ability is quickly exhausted. This is due to the effect of dynamic recovery occurring from the onset of deformation. In the soft orientation, the strain hardening is better sustained as a result of easy glide of the coplanar dislocations, on the primary slip systems, through the grain structure. The pattern of surface slip traces is compatible with the dislocation substructure arrangement observed by transmission electron microscopy (TEM). (C) 2000 Published by Elsevier Science S.A. C1 Univ Belgrade, Fac Technol & Met, YU-11000 Belgrade, Yugoslavia. Univ Calif Berkeley, Dept Mat Sci & Mineral Engn, Berkeley, CA 94720 USA. Univ Calif Berkeley, Natl Ctr Electron Microscopy, Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Romhanji, E (reprint author), Univ Belgrade, Fac Technol & Met, Karnegijeva 4, YU-11000 Belgrade, Yugoslavia. RI Mitlin , David /M-5328-2016 OI Mitlin , David /0000-0002-7556-3575 NR 45 TC 6 Z9 6 U1 1 U2 6 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 OCT 31 PY 2000 VL 291 IS 1-2 BP 160 EP 167 DI 10.1016/S0921-5093(00)00966-7 PG 8 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 352ZK UT WOS:000089249100020 ER PT J AU Chaudhuri, J Ignatiev, C Stepanov, S Tsvetkov, D Cherenkov, A Dmitriev, V Rek, Z AF Chaudhuri, J Ignatiev, C Stepanov, S Tsvetkov, D Cherenkov, A Dmitriev, V Rek, Z TI High quality GaN layers grown by hydride vapor phase epitaxy - a high resolution X-ray diffractometry and synchrotron X-ray topography study SO MATERIALS SCIENCE AND ENGINEERING B-SOLID STATE MATERIALS FOR ADVANCED TECHNOLOGY LA English DT Article DE high resolution x-ray diffractometry; synchrotron x-ray topography; GaN thin films; dislocation density AB GaN films of different thicknesses grown on 6H-SiC (00.1) by hydride vapor-phase epitaxy(HVPE) method were characterized by high resolution X-ray diffractometry and synchrotron X-ray topography, Calculations of thermal stresses gave approximately same results as experimental stress indicating that most of the stress in the film is due to the difference in thermal expansion coefficient between the him and substrate. The lowest dislocation density (i.e. 6.64 x 10(8) cm(-2)) in GaN was estimated for the sample, which has the highest thickness of GaN layer. Also comparing two different 6H-SiC substrates grown by sublimation and Lely techniques, the substrate grown by sublimation was found to be the better substrate to grow GaN thin film with rower dislocation density. Synchrotron X-ray topography revealed a number of defects including mosaic structure or local bending, low angle grain boundaries; cracks and micropores. Micropores originated at the 6H-SiC substrate went all the way through GaN films as revealed in the reflection topographs. (C) 2000 Elsevier Science S.A. Al rights reserved. C1 Wichita State Univ, Dept Mech Engn, Wichita, KS 67226 USA. Crystal Growth Res Ctr, St Petersburg 194021, Russia. TDI Inc, Gaithersburg, MD 20877 USA. Stanford Synchrotron Radiat Lab, Stanford, CA 94035 USA. RP Chaudhuri, J (reprint author), Wichita State Univ, Dept Mech Engn, Wichita, KS 67226 USA. RI Chaudhuri, Jharna/E-8863-2013 NR 9 TC 8 Z9 9 U1 1 U2 5 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0921-5107 J9 MAT SCI ENG B-SOLID JI Mater. Sci. Eng. B-Solid State Mater. Adv. Technol. PD OCT 31 PY 2000 VL 78 IS 1 BP 22 EP 27 DI 10.1016/S0921-5107(00)00507-9 PG 6 WC Materials Science, Multidisciplinary; Physics, Condensed Matter SC Materials Science; Physics GA 373QR UT WOS:000165300800004 ER PT J AU Yu, KM Walukiewicz, W Shan, W Wu, J Ager, JW Haller, EE Geisz, JF Ridgway, MC AF Yu, KM Walukiewicz, W Shan, W Wu, J Ager, JW Haller, EE Geisz, JF Ridgway, MC TI Nitrogen-induced enhancement of the free electron concentration in sulfur implanted GaNxAs1-x SO APPLIED PHYSICS LETTERS LA English DT Article ID BAND-GAP ENERGY; SEMICONDUCTORS; GANAS; GAAS AB We have achieved a large increase of the activation efficiency of sulfur atoms implanted into GaNxAs1-x thin films. For thin films with only 0.8% N content, we find a maximum free electron concentration of > 6x10(18) cm(-3) for implanted S concentration higher than 10(19) cm(-3), about 20 times larger than that in semi-insulating GaAs implanted and annealed under the same conditions. This large increase of the free electron concentration can be quantitatively explained with the recently developed band anticrossing model. (C) 2000 American Institute of Physics. [S0003-6951(00)02544-4]. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Ctr Adv Mat, Berkeley, CA 94720 USA. Natl Renewable Energy Lab, Golden, CO 80401 USA. Australian Natl Univ, Res Sch Phys Sci & Engn, Canberra, ACT, Australia. RP Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Ctr Adv Mat, Berkeley, CA 94720 USA. EM kmyu@lbl.gov RI Wu, Junqiao/G-7840-2011; Yu, Kin Man/J-1399-2012; Ridgway, Mark/D-9626-2011; OI Wu, Junqiao/0000-0002-1498-0148; Yu, Kin Man/0000-0003-1350-9642; Ridgway, Mark/0000-0002-0642-0108; Ager, Joel/0000-0001-9334-9751 NR 21 TC 29 Z9 29 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 0003-6951 EI 1077-3118 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD OCT 30 PY 2000 VL 77 IS 18 BP 2858 EP 2860 AR PII [S0003-6951(00)02544-4] DI 10.1063/1.1320872 PG 3 WC Physics, Applied SC Physics GA 366QV UT WOS:000090016800026 ER PT J AU Boyle, TJ Pedrotty, DM Alam, TM Vick, SC Rodriguez, MA AF Boyle, TJ Pedrotty, DM Alam, TM Vick, SC Rodriguez, MA TI Structural diversity in solvated lithium aryloxides. Syntheses, characterization, and structures of [Li(OAr)(THF)(x)](n) and [Li(OAr)(py)(x)](2) complexes where OAr=OC6H5, OC6H4(2-Me), OC6H3(2,6-(Me))(2), OC6H4(2-Pr-i), OC6H3(2,6-(Pr-i))(2), OC6H4(2-Bu-t), OC6H3(2,6-(Bu-t))(2) SO INORGANIC CHEMISTRY LA English DT Article ID X-RAY STRUCTURES; CRYSTAL-STRUCTURES; TITANIUM(IV) NEOPENTOXIDES; MOLECULAR-STRUCTURE; ALKOXIDES; PRECURSORS; COORDINATION; AGGREGATION; GLASSES AB A series of sterically varied aryl alcohols H-OAr [OAr = OC6H5 (OPh), OC6H4(2-Me) (oMP), OC6H3(2,6-(Me))(2) (DMP), OC6H4(2-Pr-i) (oPP), OC6H3(2,6-(Pr-i))(2) (DIP), OC6H4(2-Bu-t) (oBP), OC6H3(2,6-(Bu-t))(2) (DBP); Me = CH3, Pr-i = CHMe2, and Bu-t = CMe3] were reacted with LiN(SiMe3)(2) in a Lewis basic solvent [tetrahydrofuran (THF) or pyridine (py)] to generate the appropriate "Li(OAr)(solv)(x)". In the presence of THF, the OPh derivative was previously identified as the hexagonal prismatic complex [Li(OPh)(THF)](6); however, the structure isolated from the above route proved to be the tetranuclear species [Li(OPh)(THF)](4) (1). The other "Li(OAr)(THF)(x)" products isolated were characterized by single-crystal X-ray diffraction as [Li(OAr)(THF)](4) [OAr = oMP (2), DMP (3), oPP (4)1, [Li(DIP)(THF)](3) (5), [Li(oBP)(THF)(2)](2), (6), and [Li(DBP)(THF)](2), (7). The tetranuclear species (1-4) consist of symmetric cubes of alternating tetrahedral Li and pyramidal O atoms, with terminal THF solvent molecules bound to each metal center. The trinuclear species 5 consists of a six-membered ring of alternating trigonal planar Li and bridging O atoms, with one THF solvent molecule bound to each metal center. Compound 6 possesses two Li atoms that adopt tetrahedral geometries involving two bridging oBP and two terminal THF ligands. The structure of 7 was identical to the previously reported [Li(DBP)(THF)](2) species, but different unit cell parameters were observed. Compound 7 varies from 6 in that only one solvent molecule is bound to each Li metal center of 7 because of the steric bulk of the DBP ligand. In contrast to the structurally diverse THF adducts, when py was used as the solvent, the appropriate "Li(OAr)(py)(x)" complexes were isolated as [Li(OAr)(py)(2)](2) (OAr = OPh (8), oMP (9), DMP (10), oPP (11), DIP (12), oBP (13)) and [Li-(DBP)(py)](2) (14). Compounds 8-13 adopt a dinuclear, edge-shared tetrahedral complex. For 14, because of the steric crowding of the DBP ligand, only one py is coordinated, yielding a dinuclear fused trigonal planar arrangement. Two additional structure types were also characterized for the DIP ligand: [Li(DIP)(H-DIP)(py)](2) (12b) and [Li-2(DIP)(2)(py)(3)] (12c). Multinuclear (Li-6,Li-7 and C-13) solid-state MAS NMR spectroscopic studies indicate that the bulk powder possesses several Li environments for "transitional ligands" of the THF complexes; however, the py adducts possess only one Li environment, which is consistent with the solid-state structures. Solution NMR studies indicate that "transitional" compounds of the THF precursors display multiple species in solution whereas the py adducts display only one lithium environment. C1 Sandia Natl Labs, Adv Mat Lab, Albuquerque, NM 87106 USA. RP Boyle, TJ (reprint author), Sandia Natl Labs, Adv Mat Lab, 1001 Univ Blvd SE, Albuquerque, NM 87106 USA. NR 26 TC 92 Z9 92 U1 0 U2 5 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 OCT 30 PY 2000 VL 39 IS 22 BP 5133 EP 5146 DI 10.1021/ic000432a PG 14 WC Chemistry, Inorganic & Nuclear SC Chemistry GA 372BF UT WOS:000165213200022 PM 11233212 ER PT J AU Lim, JK Negash, K Hanrahan, SM VanBrocklin, HF AF Lim, JK Negash, K Hanrahan, SM VanBrocklin, HF TI Synthesis of 4-(3 '-[I-125]iodoanilino)-6,7-dialkoxyquinazolines: Radiolabeled epidermal growth factor receptor tyrosine kinase inhibitors SO JOURNAL OF LABELLED COMPOUNDS & RADIOPHARMACEUTICALS LA English DT Article DE epidermal growth factor receptor; iodine-125; PD153035; quinazoline; tyrosine kinase inhibitor ID HUMAN BREAST-CANCER AB The preparation of two radioiodinated analogs of the epidermal growth factor receptor tyrosine kinase (EGFrTK) inhibitor PD153035 (4-(3'-bromoanilino)-6,7-dimethoxyquinazoline) are reported herein. The two analogs, 4-(3'-[I-125]iodoanilino)-6,7-dimethoxyquinazoline and 4-(3'-[I-125]iodoanilino)-6,7-diethoxyquinazoline, were synthesized via iododestannylation of the corresponding 4-(3'-trimethylstannylanilino)-6,7-dialkoxyquinazolines to form the desired I-125 labeled products in good yield, high radiochemical purity (>99%) and high specific activity. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Calif San Francisco, Dept Radiol, San Francisco, CA 94143 USA. RP VanBrocklin, HF (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, 1 Cyclotron Rd,MS 55-121, Berkeley, CA 94720 USA. NR 24 TC 10 Z9 10 U1 0 U2 0 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 0362-4803 J9 J LABELLED COMPD RAD JI J. Label. Compd. Radiopharm. PD OCT 30 PY 2000 VL 43 IS 12 BP 1183 EP 1191 DI 10.1002/1099-1344(20001030)43:12<1183::AID-JLCR405>3.0.CO;2-N PG 9 WC Biochemical Research Methods; Chemistry, Medicinal; Chemistry, Analytical SC Biochemistry & Molecular Biology; Pharmacology & Pharmacy; Chemistry GA 365ML UT WOS:000089955000005 ER PT J AU Schneider, IF Orel, AE Suzor-Weiner, A AF Schneider, IF Orel, AE Suzor-Weiner, A TI Channel mixing effects in the dissociative recombination of H-3(+) with slow electrons SO PHYSICAL REVIEW LETTERS LA English DT Article ID STATES; D-3(+); H-3+; HEH+ AB We discuss the low-energy dissociative recombination of H-3(+) which strongly influences the abundance: of this ion in diffuse interstellar molecular clouds. The kinetic couplings between the ionization continuum and the dissociative ground state of H-3 have been used as input to a two-dimensional wave packet calculation of dissociation dynamics. The cross section obtained for direct dissociative recombination is much smaller than the latest experimental results. However, a multichannel quantum defect treatment shows that an indirect mechanism via bound Rydberg states of H-3 prevails for this process. C1 Univ Havre, Lab Mecan, F-76058 Le Havre, France. Univ Paris Sud, Photophys Mol Lab, F-91405 Orsay, France. Natl Inst Lasers Plasma & Radiat Phys, Bucharest, Romania. Univ Calif Lawrence Livermore Natl Lab, Dept Appl Sci, Livermore, CA 94550 USA. Chim Phys Lab, F-75234 Paris, France. RP Schneider, IF (reprint author), Univ Havre, Lab Mecan, BP 540, F-76058 Le Havre, France. NR 18 TC 45 Z9 45 U1 1 U2 4 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD OCT 30 PY 2000 VL 85 IS 18 BP 3785 EP 3788 DI 10.1103/PhysRevLett.85.3785 PG 4 WC Physics, Multidisciplinary SC Physics GA 368ZA UT WOS:000090146300011 ER PT J AU Andruszkow, J Aune, B Ayvazyan, V Baboi, N Bakker, R Balakin, V Barni, D Bazhan, A Bernard, M Bosotti, A Bourdon, JC Brefeld, W Brinkmann, R Buhler, S Carneiro, JP Castellano, M Castro, P Catani, L Chel, S Cho, Y Choroba, S Colby, ER Decking, W Den Hartog, P Desmons, M Dohlus, M Edwards, D Edwards, HT Faatz, B Feldhaus, J Ferrario, M Fitch, MJ Flottmann, K Fouaidy, M Gamp, A Garvey, T Gerth, C Geitz, M Gluskin, E Gretchko, V Hahn, U Hartung, WH Hubert, D Huning, M Ischebek, R Jablonka, M Joly, JM Juillard, M Junquera, T Jurkiewicz, P Kabel, A Kahl, J Kaiser, H Kamps, T Katelev, VV Kirchgessner, JL Korfer, M Kravchuk, L Kreps, G Krzywinski, J Lokajczyk, T Lange, R Leblond, B Leenen, M Lesrel, J Liepe, M Liero, A Limberg, T Lorenz, R Hua, LH Hai, LF Magne, C Maslov, M Materlik, G Matheisen, A Menzel, J Michelato, P Moller, WD Mosnier, A Muller, UC Napoly, O Novokhatski, A Omeich, M Padamsee, HS Pagani, C Peters, F Petersen, B Pierini, P Pfluger, J Piot, P Ngoc, BP Plucinski, L Proch, D Rehlich, K Reiche, S Reschke, D Reyzl, I Rosenzweig, J Rossbach, J Roth, S Saldin, EL Sandner, W Sanok, Z Schlarb, H Schmidt, G Schmuser, P Schneider, JR Schneidmiller, EA Schreiber, HJ Schreiber, S Schutt, P Sekutowicz, J Serafini, L Sertore, D Setzer, S Simrock, S Sonntag, B Sparr, B Stephan, F Sytchev, VA Tazzari, S Tazzioli, F Tigner, M Timm, M Tonutti, M Trakhtenberg, E Treusch, R Trines, D Verzilov, V Vielitz, T Vogel, V Von Walter, G Wanzenberg, R Weiland, T Weise, H Weisend, J Wendt, M Werner, M White, MM Will, I Wolff, S Yurkov, MV Zapfe, K Zhogolev, P Zhou, F AF Andruszkow, J Aune, B Ayvazyan, V Baboi, N Bakker, R Balakin, V Barni, D Bazhan, A Bernard, M Bosotti, A Bourdon, JC Brefeld, W Brinkmann, R Buhler, S Carneiro, JP Castellano, M Castro, P Catani, L Chel, S Cho, Y Choroba, S Colby, ER Decking, W Den Hartog, P Desmons, M Dohlus, M Edwards, D Edwards, HT Faatz, B Feldhaus, J Ferrario, M Fitch, MJ Flottmann, K Fouaidy, M Gamp, A Garvey, T Gerth, C Geitz, M Gluskin, E Gretchko, V Hahn, U Hartung, WH Hubert, D Huning, M Ischebek, R Jablonka, M Joly, JM Juillard, M Junquera, T Jurkiewicz, P Kabel, A Kahl, J Kaiser, H Kamps, T Katelev, VV Kirchgessner, JL Korfer, M Kravchuk, L Kreps, G Krzywinski, J Lokajczyk, T Lange, R Leblond, B Leenen, M Lesrel, J Liepe, M Liero, A Limberg, T Lorenz, R Hua, LH Hai, LF Magne, C Maslov, M Materlik, G Matheisen, A Menzel, J Michelato, P Moller, WD Mosnier, A Muller, UC Napoly, O Novokhatski, A Omeich, M Padamsee, HS Pagani, C Peters, F Petersen, B Pierini, P Pfluger, J Piot, P Ngoc, BP Plucinski, L Proch, D Rehlich, K Reiche, S Reschke, D Reyzl, I Rosenzweig, J Rossbach, J Roth, S Saldin, EL Sandner, W Sanok, Z Schlarb, H Schmidt, G Schmuser, P Schneider, JR Schneidmiller, EA Schreiber, HJ Schreiber, S Schutt, P Sekutowicz, J Serafini, L Sertore, D Setzer, S Simrock, S Sonntag, B Sparr, B Stephan, F Sytchev, VA Tazzari, S Tazzioli, F Tigner, M Timm, M Tonutti, M Trakhtenberg, E Treusch, R Trines, D Verzilov, V Vielitz, T Vogel, V Von Walter, G Wanzenberg, R Weiland, T Weise, H Weisend, J Wendt, M Werner, M White, MM Will, I Wolff, S Yurkov, MV Zapfe, K Zhogolev, P Zhou, F TI First observation of self-amplified spontaneous emission in a free-electron laser at 109 nm wavelength SO PHYSICAL REVIEW LETTERS LA English DT Article ID TESLA-TEST-FACILITY; VUV-FEL AB We present the first observation of self-amplified spontaneous emission (SASE) in a free-electron laser (FEL) in the vacuum ultraviolet regime at 109 nm wavelength (11 eV). The observed free-electron laser gain (approximately 3000) and the radiation characteristics, such as dependency on bunch charge, angular distribution, spectral width, and intensity fluctuations, are all consistent with the present models for SASE FELs. C1 Inst Phys Nucl, PL-3055 Krakow, Poland. Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. BESSY, D-12489 Berlin, Germany. Branch Inst Nucl Phys, Protvino 142284, Moscow Region, Russia. CEA Saclay, F-91191 Gif Sur Yvette, France. Darmstadt Univ Technol, FB18, Fachgebiet TEMF, D-64289 Darmstadt, Germany. DESY, D-22603 Hamburg, Germany. DESY, D-15738 Zeuthen, Germany. Stanislaw Staszic Univ Min & Met, Fac Phys & Nucl Techniques, PL-30059 Krakow, Poland. Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Hamburg, Inst Phys Expt, D-20603 Hamburg, Germany. Inst High Energy Phys, FEL Lab, Beijing 100080, Peoples R China. Inst High Energy Phys, Protvino 142284, Moscow Region, Russia. Ist Nazl Fis Nucl, Lab Nazl Frascati, I-00044 Frascati, Italy. INFN Milano, LASA, I-20090 Segrate, MI, Italy. Univ Rome 2, Ist Nazl Fis Nucl, I-00100 Rome, Italy. Russian Acad Sci, Inst Nucl Res, Moscow 117312, Russia. Polish Acad Sci, Inst Phys, PL-02668 Warsaw, Poland. IN2P3, CNRS, Inst Phys Nucl, F-91406 Orsay, France. Joint Inst Nucl Res, Dubna 141980, Moscow Region, Russia. Univ Paris Sud, Lab Accelerateur Lineaire, IN2P3, CNRS, F-91898 Orsay, France. Max Born Inst, D-12489 Berlin, Germany. Cornell Univ, Newman Lab, Ithaca, NY 14850 USA. Rhein Westfal TH Aachen, Phys Zentrum, Phys Inst 3A, D-52056 Aachen, Germany. Univ Calif Los Angeles, Dept Phys & Astron, Los Angeles, CA 90095 USA. Univ Rochester, Dept Phys & Astron, Rochester, NY 14627 USA. Yerevan Phys Inst, Yerevan 375036, Armenia. RP Rossbach, J (reprint author), Inst Phys Nucl, Ul Kawiory 26 A, PL-3055 Krakow, Poland. RI Fitch, Michael/E-5757-2011; Pierini, Paolo/J-3555-2012; Plucinski, Lukasz/J-4987-2013; Feldhaus, Josef/C-1130-2014; bourdon, jean-christophe/A-4439-2008; Treusch, Rolf/C-3935-2015; Bosotti, Angelo/I-4633-2015; Roth, Stefan/J-2757-2016 OI piot, philippe/0000-0002-4799-292X; PAGANI, CARLO/0000-0003-4962-5741; Simrock, Stefan/0000-0002-1116-5316; Fitch, Michael/0000-0002-2494-9486; Pierini, Paolo/0000-0002-3062-6181; Plucinski, Lukasz/0000-0002-6865-7274; Treusch, Rolf/0000-0001-8479-8862; Bosotti, Angelo/0000-0002-3037-7605; Roth, Stefan/0000-0003-3616-2223 NR 29 TC 246 Z9 254 U1 4 U2 29 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 OCT 30 PY 2000 VL 85 IS 18 BP 3825 EP 3829 DI 10.1103/PhysRevLett.85.3825 PG 5 WC Physics, Multidisciplinary SC Physics GA 368ZA UT WOS:000090146300021 ER PT J AU Vegge, T Rasmussen, T Leffers, T Pedersen, OB Jacobsen, KW AF Vegge, T Rasmussen, T Leffers, T Pedersen, OB Jacobsen, KW TI Determination of the of rate cross slip of screw dislocations SO PHYSICAL REVIEW LETTERS LA English DT Article ID METALS; SIMULATIONS; PLASTICITY; DIFFUSION; CU AB The rate for cross slip of screw dislocations during annihilation of screw dipoles in copper is determined by molecular dynamics simulations. The temperature dependence of the rate is seen to obey an Arrhenius behavior in the investigated temperature range: 225-375 K. The activation energy and the effective attempt frequency can therefore he extracted from the simulations. The transition state energy for the annihilation process is calculated by identifying the transition state using the nudged elastic band path technique. The two activation energies agree very well, indicating that transition state theory is applicable for this type of process. C1 Tech Univ Denmark, CAMP, DK-2800 Lyngby, Denmark. Tech Univ Denmark, Dept Phys, DK-2800 Lyngby, Denmark. Riso Natl Lab, Dept Mat Res, DK-4000 Roskilde, Denmark. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Vegge, T (reprint author), Tech Univ Denmark, CAMP, Bldg 307, DK-2800 Lyngby, Denmark. RI Jacobsen, Karsten/B-3602-2009; Vegge, Tejs/A-9419-2011 OI Jacobsen, Karsten/0000-0002-1121-2979; Vegge, Tejs/0000-0002-1484-0284 NR 27 TC 37 Z9 37 U1 1 U2 15 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD OCT 30 PY 2000 VL 85 IS 18 BP 3866 EP 3869 DI 10.1103/PhysRevLett.85.3866 PG 4 WC Physics, Multidisciplinary SC Physics GA 368ZA UT WOS:000090146300031 ER PT J AU Koshelev, AE Aranson, IS AF Koshelev, AE Aranson, IS TI Resonances, instabilities, and structure selection of driven Josephson lattice in layered superconductors SO PHYSICAL REVIEW LETTERS LA English DT Article ID PARALLEL MAGNETIC-FIELDS; SINGLE-CRYSTAL WHISKERS; COLLECTIVE MODE; VORTEX LATTICE; JUNCTIONS; VORTICES; FLOW; BI2SR2CACU2O8+Y; EXCITATION; MOTION AB We investigate the dynamics of the Josephson vortex lattice in layered high-T-c superconductors at high magnetic fields. It is shown that the average electric current depends on the lattice structure and is resonantly enhanced when the Josephson frequency matches the frequency of the plasma mode. We find the stability regions of a moving lattice. It is shown that a specific lattice structure at a given velocity is uniquely selected by the boundary conditions; at small velocities a periodic triangular lattice is stable and looses its stability at some critical velocity. At even higher velocities, a structure close to a rectangular lattice is restored. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Koshelev, AE (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Aranson, Igor/I-4060-2013; Koshelev, Alexei/K-3971-2013 OI Koshelev, Alexei/0000-0002-1167-5906 NR 23 TC 43 Z9 43 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 OCT 30 PY 2000 VL 85 IS 18 BP 3938 EP 3941 DI 10.1103/PhysRevLett.85.3938 PG 4 WC Physics, Multidisciplinary SC Physics GA 368ZA UT WOS:000090146300049 ER PT J AU Keimer, B Casa, D Ivanov, A Lynn, JW von Zimmermann, M Hill, JP Gibbs, D Taguchi, Y Tokura, Y AF Keimer, B Casa, D Ivanov, A Lynn, JW von Zimmermann, M Hill, JP Gibbs, D Taguchi, Y Tokura, Y TI Spin dynamics and orbital state in LaTiO3 SO PHYSICAL REVIEW LETTERS LA English DT Article ID LAMNO3; SCATTERING; CRYSTAL; YVO3 AB A neutron scattering study of the Mott-Hubbard insulator LaTiO3 (T-N = 132 K)reveals a spin wave spectrum that is well described by a nearest-neighbor superexchange constant J = 15.5 meV and a small Dzyaloshinskii-Moriya interaction (D = 1.1 meV). The nearly isotropic spin wave spectrum is surprising in view of the absence of a static Jahn-Teller distortion that could quench the orbital angular momentum, and it may indicate strong orbital fluctuations. A resonant x-ray scattering study has uncovered no evidence of orbital order in LaTiO3. C1 Max Planck Inst Festkorperforsch, D-70569 Stuttgart, Germany. Princeton Univ, Dept Phys, Princeton, NJ 08544 USA. Inst Max Von Laue Paul Langevin, F-38042 Grenoble, France. Natl Inst Stand & Technol, Ctr Neutron Res, Gaithersburg, MD 20899 USA. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Univ Tokyo, Dept Appl Phys, Tokyo 113, Japan. RP Keimer, B (reprint author), Max Planck Inst Festkorperforsch, D-70569 Stuttgart, Germany. RI Taguchi, Yasujiro/A-3048-2010; Tokura, Yoshinori/C-7352-2009; Casa, Diego/F-9060-2016 NR 22 TC 154 Z9 155 U1 2 U2 32 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 OCT 30 PY 2000 VL 85 IS 18 BP 3946 EP 3949 DI 10.1103/PhysRevLett.85.3946 PG 4 WC Physics, Multidisciplinary SC Physics GA 368ZA UT WOS:000090146300051 ER PT J AU Gweon, GH Denlinger, JD Allen, JW Olson, CG Hochst, H Marcus, J Schlenker, C AF Gweon, GH Denlinger, JD Allen, JW Olson, CG Hochst, H Marcus, J Schlenker, C TI Non-Fermi liquid angle resolved photoemission line shapes of Li0.9Mo6O17 SO PHYSICAL REVIEW LETTERS LA English DT Editorial Material C1 Univ Michigan, Randall Lab Phys, Ann Arbor, MI 48109 USA. Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Univ Wisconsin, Ctr Synchrotron Radiat, Stoughton, WI 53589 USA. CNRS, LEPES, F-38042 Grenoble 9, France. RP Gweon, GH (reprint author), Univ Michigan, Randall Lab Phys, Ann Arbor, MI 48109 USA. NR 5 TC 16 Z9 16 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 OCT 30 PY 2000 VL 85 IS 18 BP 3985 EP 3985 DI 10.1103/PhysRevLett.85.3985 PG 1 WC Physics, Multidisciplinary SC Physics GA 368ZA UT WOS:000090146300066 ER PT J AU Smith, KE Xue, JY Duda, LC Fedorov, AV Johnson, PD McCarroll, W Greenblatt, M AF Smith, KE Xue, JY Duda, LC Fedorov, AV Johnson, PD McCarroll, W Greenblatt, M TI Non-Fermi liquid angle resolved photoemission line shapes of Li0.9Mo6O17 - Reply SO PHYSICAL REVIEW LETTERS LA English DT Editorial Material C1 Boston Univ, Dept Phys, Boston, MA 02215 USA. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Rutgers State Univ, Dept Chem, New Brunswick, NJ 08903 USA. RP Duda, LC (reprint author), Boston Univ, Dept Phys, 590 Commonwealth Ave, Boston, MA 02215 USA. NR 3 TC 8 Z9 8 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD OCT 30 PY 2000 VL 85 IS 18 BP 3986 EP 3986 DI 10.1103/PhysRevLett.85.3986 PG 1 WC Physics, Multidisciplinary SC Physics GA 368ZA UT WOS:000090146300067 ER PT J AU Elmustafa, AA Eastman, JA Rittner, MN Weertman, JR Stone, DS AF Elmustafa, AA Eastman, JA Rittner, MN Weertman, JR Stone, DS TI Indentation size effect: Large grained aluminum versus nanocrystalline aluminum-zirconium alloys SO SCRIPTA MATERIALIA LA English DT Article DE indentation size effect; hardness; nanoindention; aluminum; nanocrystalline aluminum-zirconium; contact stiffness ID STRAIN GRADIENT PLASTICITY; SINGLE-CRYSTALS; HARDNESS C1 Univ Wisconsin, Madison, WI USA. Argonne Natl Lab, Div Sci Mat, Argonne, IL 60439 USA. Northwestern Univ, Evanston, IL USA. RP Elmustafa, AA (reprint author), NASA, Langley Res Ctr, Ctr Adv Computat Technol, UVA, Mail Stop 201, Hampton, VA 23681 USA. RI Weertman, Julia/B-7540-2009; Eastman, Jeffrey/E-4380-2011; Stone, Donald/A-7496-2016; OI Eastman, Jeff/0000-0002-0847-4265 NR 18 TC 32 Z9 33 U1 1 U2 15 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1359-6462 J9 SCRIPTA MATER JI Scr. Mater. PD OCT 30 PY 2000 VL 43 IS 10 BP 951 EP 955 DI 10.1016/S1359-6462(00)00520-0 PG 5 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 373AK UT WOS:000165266100014 ER PT J AU Kende, H AF Kende, H TI Biochemistry and molecular biology of plants SO SCIENCE LA English DT Book Review C1 Michigan State Univ, US DOE, Plant Res Lab, E Lansing, MI 48824 USA. RP Kende, H (reprint author), Michigan State Univ, US DOE, Plant Res Lab, E Lansing, MI 48824 USA. NR 1 TC 1 Z9 1 U1 10 U2 22 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 OCT 27 PY 2000 VL 290 IS 5492 BP 719 EP 719 DI 10.1126/science.290.5492.719 PG 1 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 367ND UT WOS:000090067600026 ER PT J AU Brinks, HW Yartys, VA Hauback, BC Fjellvag, H Yvon, K Gingl, F Vogt, T AF Brinks, HW Yartys, VA Hauback, BC Fjellvag, H Yvon, K Gingl, F Vogt, T TI The magnetic structure of TbNiAlD1.1 SO JOURNAL OF ALLOYS AND COMPOUNDS LA English DT Article DE magnetic structure; terbium nickel aluminium deuteride; crystal structure; metal hydride; neutron diffraction ID NEUTRON-DIFFRACTION; CRYSTAL-STRUCTURE; HYDROGEN AB The magnetic structure of orthorhombic TbNiAID(1.1) was determined by powder neutron diffraction at 3.8 and 10 K, below the antiferromagnetic ordering temperature T-N=11 K. The unit cell is doubled in b and c directions compared to the nuclear unit cell (space group Amm2; at 3.8 K a=3.6554; b=12.3954; c=7.6316 Angstrom), and the magnetic moments are confined to the be plane with main component along c. The magnetic structure is different from TbNiAl and TbNiAID(0.3) which both have ordered magnetic moments along the corresponding a axis. The magnetic moments of Tb1 and Tb2 at 3.8 K are 6.8 and 5.7 mu(B), respectively On heating to 10 K, the type of magnetic structure is not changed, however, mu(Tb) are decreased to 2.9 mu(B) (Tb1) and 5.4 mu(B) (Tb2). (C) 2000 Elsevier Science S.A. All rights reserved. C1 Inst Energy Technol, N-2027 Kjeller, Norway. Univ Oslo, Dept Chem, N-0315 Oslo, Norway. Univ Geneva, Lab Cristallog, CH-1211 Geneva, Switzerland. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Yartys, VA (reprint author), Inst Energy Technol, POB 40, N-2027 Kjeller, Norway. RI Vogt, Thomas /A-1562-2011 OI Vogt, Thomas /0000-0002-4731-2787 NR 8 TC 6 Z9 6 U1 0 U2 2 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 OCT 26 PY 2000 VL 311 IS 2 BP 114 EP 119 DI 10.1016/S0925-8388(00)01034-3 PG 6 WC Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering GA 360NF UT WOS:000089673600005 ER PT J AU Paskach, TJ Hilsenbeck, SJ Thompson, RK McCarley, RE Schrader, GL AF Paskach, TJ Hilsenbeck, SJ Thompson, RK McCarley, RE Schrader, GL TI Synthesis and characterization of a novel platinum molybdenum sulfide containing the Mo6S8 cluster SO JOURNAL OF ALLOYS AND COMPOUNDS LA English DT Article DE metal sulfide clusters; molybdenum cluster catalysts; hydrodesulfurization ID SUPERCONDUCTING CHEVREL PHASES; HYDRODESULFURIZATION CATALYSIS; CHALCOGENIDES AB Our previously discovered, low-temperature route for the preparation of ternary molybdenum sulfide cluster compounds containing the Mo6S8 structure has been used to synthesize a new Pt (PtMoS) material. Ion-exchange of amorphous NaMoS with [Pt(NH3)(4)]Cl-2 led to incorporation of the [Pt(NH3)(4)](2+) cation yielding [Pt(NH3)(4)](Mo6S8)S . x(H2O/MeOH), as confirmed by infrared and X-ray photoelectron spectroscopic (XPS) characterization. XPS indicated that this new platinum material had the reduced molybdenum oxidation state characteristic of ternary molybdenum sulfides containing the Mo6S8 structural unit. The surface area of the new PtMoS material was as high as 135 m(2)/g. Attempts to convert the PtMoS material to a crystalline Chevrel phase PtMo6S8 by H-2 reduction at elevated temperatures were unsuccessful. However, H-2 treatment at 400 degrees C provided material retaining the Mo6S8 cluster, probably as amorphous Pt(Mo6S8)S. The latter material is a very active hydrodesulfurization (HDS) catalyst, with much higher activity compared to other more stable compounds containing the Mo6S8 cluster unit. (C) 2000 Elsevier Science S.A. All rights reserved. C1 Iowa State Univ Sci & Technol, Dept Chem Engn, Ames, IA 50011 USA. 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 Schrader, GL (reprint author), Iowa State Univ Sci & Technol, Dept Chem Engn, Ames, IA 50011 USA. NR 24 TC 10 Z9 10 U1 1 U2 13 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 OCT 26 PY 2000 VL 311 IS 2 BP 169 EP 180 DI 10.1016/S0925-8388(00)01107-5 PG 12 WC Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering GA 360NF UT WOS:000089673600013 ER PT J AU Zeng, LM Franzen, HF AF Zeng, LM Franzen, HF TI Lanthanum rhodium antimonide, La0.1Rh8Sb24 SO JOURNAL OF ALLOYS AND COMPOUNDS LA English DT Article DE rare earth compounds; transition metal compound; X-ray diffraction; structure determination ID TERNARY; LAFE4P12; ND; SM AB The structure of lanthanum rhodium antimonide, La0.1Rh8Sb24, has been determined from single-crystal X-ray data, It crystallizes in the cubic space group Im (3) over bar (No.204), with a=9.2213(15) Angstrom, V=784.1(2) Angstrom(3) and the LaFe4P12 structure type. (C) 2000 Elsevier Science S.A. All rights reserved. C1 Guangxi Univ, Inst Mat Sci, Nanning 530004, Peoples R China. Iowa State Univ Sci & Technol, Ames Lab, US DOE, Ames, IA 50011 USA. RP Zeng, LM (reprint author), Guangxi Univ, Inst Mat Sci, Nanning 530004, Peoples R China. NR 10 TC 4 Z9 4 U1 0 U2 1 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 OCT 26 PY 2000 VL 311 IS 2 BP 224 EP 225 DI 10.1016/S0925-8388(00)01045-8 PG 2 WC Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering GA 360NF UT WOS:000089673600020 ER PT J AU Zeng, LM Franzen, HF AF Zeng, LM Franzen, HF TI Single-crystal structure investigation of NdNi and NdNi5 SO JOURNAL OF ALLOYS AND COMPOUNDS LA English DT Article DE rare earth compounds; transition metal compound; X-ray diffraction; structure determination AB The structures of NdNi and NdNi, have been determined by single-crystal data. NdNi crystallizes in the orthorhombic space group Cmcm (No. 63), with a=3.8059(5) Angstrom, b=10.462(4) Angstrom, c=4.3345(12) Angstrom, Z=4, V=172.59(8) Angstrom(3) and the BCr structure type. NdNi5 crystallizes with the CaCu5 structure type, space group P6/mmm (No. 191), a=4.973(2) Angstrom, c=4.0124(11) Angstrom, Z=1 and V=85.94(5) Angstrom(3). (C) 2000 Elsevier Science S.A. All rights reserved. C1 Guangxi Univ, Inst Mat Sci, Nanning 530004, Guangxi, Peoples R China. Iowa State Univ Sci & Technol, Ames Lab, DOE, Ames, IA 50011 USA. RP Zeng, LM (reprint author), Guangxi Univ, Inst Mat Sci, Nanning 530004, Guangxi, Peoples R China. NR 4 TC 3 Z9 3 U1 0 U2 2 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 OCT 26 PY 2000 VL 311 IS 2 BP 226 EP 227 DI 10.1016/S0925-8388(00)01038-0 PG 2 WC Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering GA 360NF UT WOS:000089673600021 ER PT J AU Mo, YB Antonio, MR Scherson, DA AF Mo, YB Antonio, MR Scherson, DA TI In situ Ru K-edge X-ray absorption fine structure studies of electroprecipitated ruthenium dioxide films with relevance to supercapacitor applications SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Letter ID ELECTROCHEMICAL CAPACITORS; NEUTRON-DIFFRACTION; RUTILE-TYPE; OXIDE AB Modifications in electronic and structural aspects of RuO2 films electroprecipitated onto Au electrodes induced by changes in the applied potential have been examined in situ in aqueous 0.50 M H2SO4 by Ru K-edge X-ray absorption spectroscopy (XAS). The Fourier transform of the k(3)-weighted extended X-ray absorption fine structure (EXAFS), k(3)chi>(*) over bar * (k), for the film polarized at +1.20V vs RHE is characterized by two shells attributed to Ru-O and Ru-Ru interactions with average distances of 1.94(1) and 3.12(2) Angstrom, respectively, in agreement with results obtained ex situ for RU4+ in hydrous RuO2 by other groups. In contrast, films in the reduced state, i.e., +0.40 V vs RHE, yielded only a single shell ascribed to a Ru-O interaction at 2.02(1) Angstrom with no evidence for a distant Ru-Ru shell. The long Ru-O distance is in agreement with that reported earlier for the hydrous Ru3+ ion [Ru-(OH2)(6)](3+) in the solid state. Moreover, the difference between the average Ru-O bond lengths for the reduced and oxidized films is consistent with the difference in the ionic radii of Ru3+ and Ru4+. On, this basis it has been suggested that films in the reduced state contain Ru3+ sites, consistent with the electrochemical results, in a phase with apparently less order beyond the Ru-O coordination sphere than for hydrous RuO2. C1 Case Western Reserve Univ, Dept Chem, Cleveland, OH 44106 USA. Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. RP Scherson, DA (reprint author), Case Western Reserve Univ, Dept Chem, Cleveland, OH 44106 USA. NR 13 TC 37 Z9 37 U1 6 U2 24 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 OCT 26 PY 2000 VL 104 IS 42 BP 9777 EP 9779 DI 10.1021/jp002355a PG 3 WC Chemistry, Physical SC Chemistry GA 369QC UT WOS:000165077600003 ER PT J AU Chow, E Lin, SY Johnson, SG Villeneuve, PR Joannopoulos, JD Wendt, JR Vawter, GA Zubrzycki, W Hou, H Alleman, A AF Chow, E Lin, SY Johnson, SG Villeneuve, PR Joannopoulos, JD Wendt, JR Vawter, GA Zubrzycki, W Hou, H Alleman, A TI Three-dimensional control of light in a two-dimensional photonic crystal slab SO NATURE LA English DT Article ID NEAR-INFRARED WAVELENGTHS; BAND-GAP STRUCTURES; WAVE-GUIDE; CONFINEMENT; MODES AB Optoelectronic devices are increasingly important in communication and information technology. To achieve the necessary manipulation of light (which carries information in optoelectronic devices), considerable efforts are directed at the development of photonic crystals-periodic dielectric materials that have so-called photonic bandgaps, which prohibit the propagation of photons having energies within the bandgap region. Straightforward application of the bandgap concept is generally thought to require three-dimensional (3D) photonic crystals(1-5); their two-dimensional (2D) counterparts confine light in the crystal plane(6,7), but not in the perpendicular z direction, which inevitably leads to diffraction losses. Nonetheless, 2D photonic crystals still attract interest(8-15) because they are potentially more amenable to fabrication by existing techniques and diffraction losses need not seriously impair utility. Here we report the fabrication of a waveguide-coupled photonic crystal slab (essentially a free-standing 2D photonic crystal) with a strong 2D bandgap at wavelengths of about 1.5 mum, yet which is capable of fully controlling light in all three dimensions. These features confirm theoretical calculations(16,17) on the possibility of achieving 3D light control using 2D bandgaps, with index guiding providing control in the third dimension, and raise the prospect of being able to realize unusual photonic-crystal devices, such as thresholdless lasers(1). C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. MIT, Dept Phys, Cambridge, MA 02139 USA. RP Lin, SY (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 24 TC 306 Z9 323 U1 6 U2 83 PU MACMILLAN PUBLISHERS LTD PI LONDON PA PORTERS SOUTH, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD OCT 26 PY 2000 VL 407 IS 6807 BP 983 EP 986 PG 5 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 366XX UT WOS:000090032500037 PM 11069173 ER PT J AU Gotsman, E Levin, E Lublinsky, M Maor, U Tuchin, K AF Gotsman, E Levin, E Lublinsky, M Maor, U Tuchin, K TI Shadowing corrections and diffractive production in DIS on nuclei SO PHYSICS LETTERS B LA English DT Article ID DEEP-INELASTIC SCATTERING; PARTON DISTRIBUTIONS; CROSS-SECTION; QCD; SATURATION; LEPTOPRODUCTION; GLUON AB We calculate, in the Glauber-Mueller approach, the ratio of the diffractive dissociation cross section to the total cross section for nuclei. We observe that shadowing corrections (SC) in the calculated sigma (diff)/sigma (tot) ratio are significant, but they do not lead to a smooth energy dependence of the ratio for a proton target as was observed at HERA. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Tel Aviv Univ, Raymond & Beverly Sackler Fac Exact Sci, Sch Phys & Astron, HEP Dept, IL-69978 Tel Aviv, Israel. Brookhaven Natl Lab, New York, NY USA. Technion Israel Inst Technol, Dept Phys, IL-32000 Haifa, Israel. RP Gotsman, E (reprint author), Tel Aviv Univ, Raymond & Beverly Sackler Fac Exact Sci, Sch Phys & Astron, HEP Dept, IL-69978 Tel Aviv, Israel. NR 28 TC 21 Z9 21 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 OCT 26 PY 2000 VL 492 IS 1-2 BP 47 EP 55 DI 10.1016/S0370-2693(00)01020-0 PG 9 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 372GW UT WOS:000165226800007 ER PT J AU Harlander, RV AF Harlander, RV TI Virtual corrections to gg -> H to two loops in the heavy top limit SO PHYSICS LETTERS B LA English DT Article ID HIGGS-BOSON PRODUCTION; QCD CORRECTIONS; LEADING ORDER; CROSS-SECTION; FORM-FACTOR; COLLISIONS; JETS; SOFT; LHC AB The virtual corrections to the production cross section of a Standard Model Higgs boson are computed up to order alpha (4)(s). Using an effective Lagrangian for the limit M-t --> infinity, we evaluate the relevant massless two-loop vertex diagrams by mapping them onto three-loop two-point functions, following a method recently introduced by Baikov and Smirnov [1]. As a result, we find a gauge-invariant contribution to the total Higgs production cross section at NNLO. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Brookhaven Natl Lab, HET, Dept Phys, Upton, NY 11973 USA. RP Harlander, RV (reprint author), Brookhaven Natl Lab, HET, Dept Phys, Upton, NY 11973 USA. NR 39 TC 133 Z9 133 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 OCT 26 PY 2000 VL 492 IS 1-2 BP 74 EP 80 DI 10.1016/S0370-2693(00)01042-X PG 7 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 372GW UT WOS:000165226800011 ER PT J AU Kogut, JB Sinclair, DK AF Kogut, JB Sinclair, DK TI Tricritical scaling at the N-t=6 chiral phase transition for 2 flavour lattice QCD with staggered quarks SO PHYSICS LETTERS B LA English DT Article ID QUANTUM CHROMODYNAMICS; THERMODYNAMICS AB We have simulated lattice QCD directly in the chiral limit of zero quark mass by adding an additional, irrelevant 4-fermion interaction to the standard action. Using lattices having temporal extent of six and spatial extents of twelve and eighteen, we And that the theory with 2 massless staggered quark flavors has a second-order finite-temperature phase transition. The critical exponents beta (mag) delta and nu are measured and favour tricritical behaviour over that expected by universality arguments. The pion screening mass is consistent with zero below the transition, but is degenerate with the nonzero sigma (f(0)) mass above the transition, indicating the restoration of chiral symmetry. (C) 2000 Published by Elsevier Science B.V. C1 Univ Illinois, Dept Phys, Urbana, IL 61801 USA. Argonne Natl Lab, HEP Div, Argonne, IL 60439 USA. RP Kogut, JB (reprint author), Univ Illinois, Dept Phys, 1110 W Green St, Urbana, IL 61801 USA. RI Korol, Aleksandr/A-6244-2014; Sharyy, Viatcheslav/F-9057-2014 OI Korol, Aleksandr/0000-0001-8448-218X; Sharyy, Viatcheslav/0000-0002-7161-2616 NR 14 TC 7 Z9 7 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 OCT 26 PY 2000 VL 492 IS 1-2 BP 228 EP 232 DI 10.1016/S0370-2693(00)01050-9 PG 5 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 372GW UT WOS:000165226800030 ER PT J AU Chen, KD Xie, SB Bell, AT Iglesia, E AF Chen, KD Xie, SB Bell, AT Iglesia, E TI Alkali effects on molybdenum oxide catalysts for the oxidative dehydrogenation of propane SO JOURNAL OF CATALYSIS LA English DT Article ID X-RAY-ABSORPTION; RAMAN-SPECTROSCOPY; SELECTIVE OXIDATION; K-EDGE; ZIRCONIA; ALKANES; PROMOTERS; SUPPORT; SYSTEMS; MOO3 AB The effects of alkali oxides on the structure and on the catalytic behavior of MoOx/ZrO2 were examined for the oxidative dehydrogenation (ODH) of propane. X-ray diffraction, Raman and X-ray absorption spectroscopy, and estimates of the MoOx surface density are consistent with the predominant presence of two-dimensional polymolybdate domains in samples with similar to4 Mo/nm(2) surface density and (alkali/Mo)(at.) ratios of 0-0.2 treated in air at 773 K. The presence of alkali (Cs, K, Li) did not affect the structure of MoOx domains, but influenced their electronic and catalytic properties. Propane ODH turnover rates decreased monotonically with increasing A:Mo atomic ratio and with increasing basicity of the alkali oxide (Cs > K > Li). These basic oxides inhibit the initial reduction of MoOx in Hz by strengthening Mo-O bonds and increasing reduction activation energies. As a result, rate-determining C-H bond activation steps, which involve the local reduction of Mo6+ centers, and the overall ODH catalytic sequence proceed more slowly when alkali oxides modify the MoOx domains. The ratio of the rate constant for primary propane combustion (k(2)) to that for propane ODH (k(1)) is small (similar to0.1) and it increased slightly with increased alkali content. The ratio of the propene combustion rate constant (k(3)) to the propane ODH rate constant (k(1)) is large (15-25); it decreased with the addition of small amounts of alkali (alkali/Mo similar to 0.05) and then remained constant at higher alkali contents. The stronger inhibition of secondary propene combustion reactions relative to that of primary ODH steps reflects the weaker Lewis acidity of Mo6+ cations modified by the strongly basic alkali oxide species. These effects decrease the binding energy of propene on the sites required for C-H bond activation of both propene and propane. They also account for the lower reaction rates and for the higher selectivity observed at a given propane conversion on alkali-modified MoOx ODH catalysts. (C) 2000 Academic Press. C1 Univ Calif Berkeley, EO Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, EO Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Chem Engn, Berkeley, CA 94720 USA. RP Bell, AT (reprint author), Univ Calif Berkeley, EO Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA. RI Song, Kunshan/C-7073-2008; Iglesia, Enrique/D-9551-2017; OI Iglesia, Enrique/0000-0003-4109-1001; Bell, Alexis/0000-0002-5738-4645 NR 32 TC 79 Z9 84 U1 3 U2 26 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 OCT 25 PY 2000 VL 195 IS 2 BP 244 EP 252 DI 10.1006/jcat.2000.3025 PG 9 WC Chemistry, Physical; Engineering, Chemical SC Chemistry; Engineering GA 368FF UT WOS:000090106500003 ER PT J AU James, ER Manga, M Rose, TP Hudson, GB AF James, ER Manga, M Rose, TP Hudson, GB TI The use of temperature and the isotopes of O, H, C, and noble gases to determine the pattern and spatial extent of groundwater flow SO JOURNAL OF HYDROLOGY LA English DT Article DE springs; tracers; helium; carbon; stable isotopes; temperature ID HEAT-FLOW; OREGON CASCADES; ENVIRONMENTAL TRACERS; FRACTURED ROCK; CARBON-DIOXIDE; RIVER PLAIN; MOUNT-ETNA; CALIFORNIA; HYDROLOGY; FLUXES AB Isotopic tracer and temperature measurements at large volume cold springs in the central Oregon Cascades are used to understand the pattern of groundwater flow. Standard oxygen and hydrogen isotope interpretations are used to determine the mean recharge elevation for springs. Carbon and helium isotopes are used to measure the component of dissolved magmatic gas in the spring waters. Inferences from isotopic measurements are compared with temperature measurements made at the springs to determine whether groundwater circulates to shallow or deep depths in the subsurface. Integrating the measurements of tracers derived at the surface, tracers derived from the subsurface, and temperature measurements can thus be used to derive a three dimensional picture of groundwater flow. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Oregon, Dept Geol Sci, Eugene, OR 97403 USA. Univ Calif Lawrence Livermore Natl Lab, Analyt & Nucl Chem Div, Livermore, CA 94550 USA. RP Manga, M (reprint author), Univ Oregon, Dept Geol Sci, Eugene, OR 97403 USA. RI Manga, Michael/D-3847-2013; OI Manga, Michael/0000-0003-3286-4682 NR 51 TC 43 Z9 48 U1 1 U2 26 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-1694 J9 J HYDROL JI J. Hydrol. PD OCT 25 PY 2000 VL 237 IS 1-2 BP 100 EP 112 DI 10.1016/S0022-1694(00)00303-6 PG 13 WC Engineering, Civil; Geosciences, Multidisciplinary; Water Resources SC Engineering; Geology; Water Resources GA 366WR UT WOS:000090029700007 ER PT J AU Lee, HS Denn, MM AF Lee, HS Denn, MM TI The deformation and retraction of thermotropic LCP droplets in a flexible polymer matrix SO JOURNAL OF NON-NEWTONIAN FLUID MECHANICS LA English DT Article DE liquid crystalline polymer; blend; droplet ID SHEAR-FLOW; RHEOLOGY; RECOVERY; BLENDS; PHASE; MELT AB We have studied the initial deformation and shape recovery of droplets of a flexible polymer and a liquid crystalline polymer in a flexible thermoplastic matrix. The LCP droplets exhibit a size dependence that is not observed for the flexible polymer droplets, possibly because of the effect of orientational elasticity in the liquid crystalline polymer. (C) 2000 Elsevier Science B.V. All rights reserved. C1 CUNY City Coll, Benjamin Levich Inst Physicochem Hydrodynam, New York, NY 10031 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Sci Mat, Berkeley, CA 94720 USA. RP Denn, MM (reprint author), CUNY City Coll, Benjamin Levich Inst Physicochem Hydrodynam, New York, NY 10031 USA. OI Lee, Heon Sang/0000-0002-6806-5666 NR 12 TC 12 Z9 13 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0377-0257 J9 J NON-NEWTON FLUID JI J. Non-Newton. Fluid Mech. PD OCT 25 PY 2000 VL 93 IS 2-3 BP 315 EP 323 DI 10.1016/S0377-0257(00)00118-X PG 9 WC Mechanics SC Mechanics GA 355WK UT WOS:000089411400007 ER PT J AU Anzenbacher, P Try, AC Miyaji, H Jursikova, K Lynch, VM Marquez, M Sessler, JL AF Anzenbacher, P Try, AC Miyaji, H Jursikova, K Lynch, VM Marquez, M Sessler, JL TI Fluorinated calix[4]pyrrole and dipyrrolylquinoxaline: Neutral anion receptors with augmented affinities and enhanced selectivities SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID FLUORESCENCE DETECTION; AQUEOUS-SOLUTION; BINDING; RECOGNITION; SYSTEMS; SENSORS AB The use of the 3,4-difluoro-1H-pyrrole as a building block for the preparation of octamethyloctafluorocalix[4]pyrrole and 2,3-di(3',4'-difluoropyrrol-2'yl)quinoxaline is described. These latter two entities act as neutral anion receptors and were found to bind anions such as fluoride, chloride, or dihydrogen phosphate with an enhanced affinity compared to their non-fluorinated congeners as judged from H-1 NMR, F-19 NMR, and fluorescence emission spectroscopic analyses. The increase in affinity was especially high in case of chloride and dihydrogen phosphate anion, with the 2,3-di(3',4'-difluoropyrrol-2'-yl)quinoxaoline system, in particular, displaying an affinity for H2PO4- that was improved by 3 orders of magnitude as compared to its nun-fluorinated congener. This improvement in the affinity for the dihydrogen phosphate is accompanied by change of color from pale yellow to orange, thus allowing the use of such compounds as naked-eye sensors for phosphate anion. In the case of the octafluorocalix[4]pyrrole system X-ray diffraction analyses revealed the presence of four different macrocyclic conformations in the solid state, as well as close intermolecular contacts mediated by apparent CF- -HN hydrogen bonds. C1 Univ Texas, Dept Chem & Biochem, Austin, TX 78712 USA. Univ Texas, Inst Mol & Cellular Biol, Austin, TX 78712 USA. Univ Calif Los Alamos Natl Lab, Chem Sci & Technol Div, Los Alamos, NM 87545 USA. Kraft Gen Foods Inc, R&D, Nanotechnol Lab, Glenview, IL 60025 USA. RP Marquez, M (reprint author), Univ Texas, Dept Chem & Biochem, Austin, TX 78712 USA. RI Try, Andrew/A-5445-2008 OI Try, Andrew/0000-0001-9884-9536 NR 24 TC 252 Z9 253 U1 2 U2 20 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 OCT 25 PY 2000 VL 122 IS 42 BP 10268 EP 10272 PG 5 WC Chemistry, Multidisciplinary SC Chemistry GA 368UZ UT WOS:000090137000002 ER PT J AU Nitschke, JR Zurcher, S Tilley, TD AF Nitschke, JR Zurcher, S Tilley, TD TI New zirconocene-coupling route to large, functionalized macrocycles SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID BIPHENYL DERIVATIVES; MOLECULAR-STRUCTURE; INTERNAL-ROTATION; GASEOUS STATE; EFFICIENT; POLYMERIZATION; BIPYRIDINE; CATALYSTS; ZIRCONIUM; POLYMERS AB The development of a new macrocyclization reagent, Rosenthal's Cp2Zr(pyr)(Me3SiC drop CSiMe3), has allowed the preparation of two large, functionalized macrocycles. The diyne 5,5'-bis(4-trimethylsilylphenyl)-2,2'-bipyridine was trimerized to the bipyridine-containing macrocycle 5, and 1,4-bis(4-(trimethylsilyl)ethynylphenyl)-2,3-diphenyl-1,4-diazabuta-1,3-diene was dimerized to macrocycle 6. Both zirconocene-containing macrocycles were characterized by single-crystal X-ray diffraction. Macrocycle 5, which is cleanly converted to air-stable cyclophane 7 with benzoic acid, has a cavity of van der Waals radius 6.03 Angstrom. In general, the Cp2Zr(pyr)(Me3SiC drop CSiMe3) reagent gives higher yields of macrocycles via the coupling of diynes than does the reagent generated by addition of n-BuLi to Cp2ZrCl2. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA. RP Tilley, TD (reprint author), Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. RI Zuercher, Stefan/A-3424-2009; Nitschke, Jonathan/A-1664-2010 OI Zuercher, Stefan/0000-0001-6990-791X; Nitschke, Jonathan/0000-0002-4060-5122 NR 31 TC 73 Z9 73 U1 2 U2 13 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 OCT 25 PY 2000 VL 122 IS 42 BP 10345 EP 10352 DI 10.1021/ja0020310 PG 8 WC Chemistry, Multidisciplinary SC Chemistry GA 368UZ UT WOS:000090137000010 ER PT J AU Muller, S Wolverton, C Wang, LW Zunger, A AF Muller, S Wolverton, C Wang, LW Zunger, A TI Predicting the size- and temperature-dependent shapes of precipitates in Al-Zn alloys SO ACTA MATERIALIA LA English DT Article DE aluminum alloys; aging; computer simulation; ab initio calculation; thermodynamics ID GUINIER-PRESTON ZONES; AT-PERCENT-ZN; SMALL-ANGLE-SCATTERING; SHORT-RANGE ORDER; LOCAL-DENSITY FORMALISM; SOLID-SOLUTIONS; SPINODAL DECOMPOSITION; 1ST-PRINCIPLES THEORY; SEMICONDUCTOR ALLOYS; COMPUTER-SIMULATION AB We study theoretically the size versus shape versus temperature relation of precipitates in AI-Zn via quantum-mechanical first-principles simulations. Our parameter-free model, based on a mixed-space cluster expansion, allows the prediction of the experimentally observed size and temperature dependences of the precipitate shape. We find that aging experiments can be explained in terms of equilibrium shapes. The precipitates change from a nearly spherical to a more ellipsoidal/hexagonal shape with increasing size and decreasing temperature. They always flatten in the [111] direction, which can be interpreted as a consequence of a mechanical instability of face-centered cubic Zn when rhombohedrally distorted along [111] and a strong anisotropy of the chemical energy. The excellent agreement between experiment and theory shows that our model can be used to quantitatively predict precipitate shapes and sizes. (C) 2000 Acta Metallurgica Inc. Published by Elsevier Science Ltd. All rights reserved. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. Ford Motor Co, Res Lab, SRL MD3028, Dearborn, MI 48121 USA. RP Natl Renewable Energy Lab, Golden, CO 80401 USA. RI Wolverton, Christopher/B-7542-2009; Zunger, Alex/A-6733-2013 NR 58 TC 26 Z9 29 U1 3 U2 16 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1359-6454 EI 1873-2453 J9 ACTA MATER JI Acta Mater. PD OCT 24 PY 2000 VL 48 IS 16 BP 4007 EP 4020 DI 10.1016/S1359-6454(00)00209-3 PG 14 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 372XG UT WOS:000165258900002 ER PT J AU Chao, C Saito, S Anderson, CW Appella, E Xu, Y AF Chao, C Saito, S Anderson, CW Appella, E Xu, Y TI Phosphorylation of murine p53 at Ser-18 regulates the p53 responses to DNA damage SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article ID PROTEIN-KINASE; ES CELLS; ATM; SERINE-15; TRANSACTIVATION; ACETYLATION; ACTIVATION; APOPTOSIS; RADIATION; MUTATION AB Ser-15 of human p53 (corresponding to Ser-18 of mouse p53) is phosphorylated by ataxia-telangiectasia mutated (ATM) family kinases in response to ionizing radiation (IR) and UV light, To determine the effects of phosphorylation of endogenous murine p53 at Ser-18 on biological responses to DNA damage, we introduced a missense mutation (Ser-18 to Ala) by homologous recombination into both alleles of the endogenous p53 gene in mouse embryonic stem (ES) cells. Our analyses showed that phosphorylation of murine p53 at Ser-18 in response to IR or UV radiation was required for a full p53-mediated response to these DNA damage-inducing agents. In contrast, phosphorylation of p53 at Ser-18 was not required for ATM-dependent cellular resistance after exposure to IR, Additionally, efficient acetylation of the C terminus of p53 in response to DNA damage did not require phosphorylation of murine p53 at Ser-18. C1 Univ Calif San Diego, Div Biol, La Jolla, CA 92093 USA. Univ Calif San Diego, Ctr Canc, La Jolla, CA 92093 USA. NCI, Cell Biol Lab, NIH, Bethesda, MD 20892 USA. Brookhaven Natl Lab, Dept Biol, Upton, NY 11973 USA. RP Xu, Y (reprint author), Univ Calif San Diego, Div Biol, 9500 Gilman Dr, La Jolla, CA 92093 USA. FU NIGMS NIH HHS [GM52825] NR 38 TC 120 Z9 122 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 OCT 24 PY 2000 VL 97 IS 22 BP 11936 EP 11941 DI 10.1073/pnas.220252297 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 367PQ UT WOS:000090071000044 PM 11035798 ER PT J AU Cahoon, EB Shanklin, J AF Cahoon, EB Shanklin, J TI Substrate-dependent mutant complementation to select fatty acid desaturase variants for metabolic engineering of plant seed oils SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article ID ACYL-CARRIER-PROTEIN; THUNBERGIA-ALATA ENDOSPERM; ESCHERICHIA-COLI; TRANSGENIC TOBACCO; EXPRESSION; GENE; THIOESTERASE; SPECIFICITY; FERREDOXIN; CLONING AB We demonstrate that naturally occurring C-14 and C-16-specific acyl-acyl carrier protein (ACP) desaturases from plants can complement the unsaturated fatty acid (UFA) auxotrophy of an Escherichia coli fabA/fadR mutant. Under the same growth conditions, C-18-specific Delta (9)-stearoyl (18:0)-ACP desaturases are unable to complement the UFA auxotrophy, This difference most likely results from the presence of sufficient substrate pools of C-14 and C-16 acyl-ACPs but a relative lack of C-18 acyl-ACP pools in E, coli to support the activities of the plant fatty acid desaturase. Based on this, a substrate-dependent selection system was devised with the use of the E, coli UFA auxotroph to isolate mutants of the castor Delta (9)-18:0-ACP desaturase that display enhanced specificity for C-14 and C-16 acyl-ACPs, Using this selection system, a number of desaturase variants with altered substrate specificities were isolated from pools of randomized mutants. These included several G188L mutant isolates, which displayed a 15-fold increase in specific activity with 16:0 ACP relative to the wild-type castor Delta (9)-18:0-ACP desaturase, Expression of this mutant in Arabidopsis thaliana resulted in the accumulation of unusual monounsaturated fatty acids to amounts of >25% of the seed oil. The bacterial selection system described here thus provides a rapid means of isolating variant fatty acid desaturase activities for modification of seed oil composition. C1 Brookhaven Natl Lab, Dept Biol, Upton, NY 11973 USA. RP Shanklin, J (reprint author), Brookhaven Natl Lab, Dept Biol, Upton, NY 11973 USA. NR 32 TC 46 Z9 48 U1 0 U2 7 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 OCT 24 PY 2000 VL 97 IS 22 BP 12350 EP 12355 DI 10.1073/pnas.210276297 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 367PQ UT WOS:000090071000116 PM 11027301 ER PT J AU Muramatsu, Y Takenaka, H Ueno, Y Gullikson, EM Perera, RCC AF Muramatsu, Y Takenaka, H Ueno, Y Gullikson, EM Perera, RCC TI Chemical bonding state analysis of silicon carbide layers in Mo/SiC/Si multilayer mirrors by soft x-ray emission and absorption spectroscopy SO APPLIED PHYSICS LETTERS LA English DT Article ID ALPHA-CLUSTER CALCULATIONS AB Soft x-ray emission and absorption spectra in the C K region of Mo/SiC/Si multilayer mirrors were measured using highly brilliant synchrotron radiation to identify the chemical bonding states of the buried silicon carbide layers. Comparison with the C 2p density of state (DOS) spectra, calculated by discrete variational-X alpha molecular orbital calculations, of several SiC-based cluster models showed that the measured x-ray spectra approximately agreed with the calculated C 2p-DOS spectra of the c- and h-SiC-based SiCx models in which some silicon atoms were replaced by carbon atoms. The chemical bonding states of the silicon carbide layers in the Mo/SiC/Si multilayer mirrors were therefore estimated to be carbon-excessive silicon carbide. (C) 2000 American Institute of Physics. [S0003-6951(00)00542-8]. C1 NTT Adv Technol Corp, Tokyo 1808585, Japan. NTT, Lifestyle & Environm Res Labs, Kanagawa 2430198, Japan. Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Xray Opt, Berkeley, CA 94720 USA. RI Ueno, Yuko/H-5651-2012 NR 10 TC 11 Z9 11 U1 1 U2 3 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 OCT 23 PY 2000 VL 77 IS 17 BP 2653 EP 2655 DI 10.1063/1.1318231 PG 3 WC Physics, Applied SC Physics GA 363ZQ UT WOS:000089867900009 ER PT J AU Angadi, M Auciello, O Krauss, AR Gundel, HW AF Angadi, M Auciello, O Krauss, AR Gundel, HW TI The role of electrode material and polarization fatigue on electron emission from ferroelectric Pb(ZrxTi1-x)O-3 cathodes SO APPLIED PHYSICS LETTERS LA English DT Article ID THIN-FILMS; CERAMICS AB Electron emission from bulk Pt/PZT/Pt and RuO2/PZT/RuO2 ferroelectric cathodes is reported. The total emission current (0.8 A) and polarization fatigue are high for ferroelectric cathodes with Pt electrodes, while emission current (0.18 A) and polarization fatigue are significantly lower for cathodes with RuO2 electrodes. The data correlate with earlier results from research on ferroelectric memories, which suggest that oxygen vacancies near the electrode/ferroelectric interface and through the bulk of the ferroelectric layer play a major role in controlling the polarization switching of PZT-based capacitors and consequently in controlling the electron emission process in PZT cathodes. The strong correlation between polarization fatigue and emission observed in the present investigation provides evidence for the role of polarization inversion on the electron emission phenomenon. In addition, the data provide evidence for the role that oxygen vacancies play in controlling electron emission from PZT cathodes. (C) 2000 American Institute of Physics. [S0003-6951(00)00843-3]. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. Univ Nantes, Lab Phys Isolants & Optron, F-44322 Nantes, France. RP Angadi, M (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 20 TC 25 Z9 26 U1 0 U2 6 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 OCT 23 PY 2000 VL 77 IS 17 BP 2659 EP 2661 DI 10.1063/1.1319532 PG 3 WC Physics, Applied SC Physics GA 363ZQ UT WOS:000089867900011 ER PT J AU Cheong, HM Lee, SH Nelson, BP Mascarenhas, A Deb, SK AF Cheong, HM Lee, SH Nelson, BP Mascarenhas, A Deb, SK TI Light-induced long-range hydrogen motion in hydrogenated amorphous silicon at room temperature SO APPLIED PHYSICS LETTERS LA English DT Article ID METASTABILITY; DIFFUSION; SI AB We present evidence for long-range hydrogen motion in hydrogenated amorphous silicon (a-Si:H) under room-temperature illumination, by monitoring the changes in the Raman spectrum of an a-WO3 overlayer with illumination. We observe that illumination causes hydrogen to diffuse out of the a-Si:H layer into the a-WO3 layer. This hydrogen motion is observed to saturate after about 30 min when the a-Si:H is illuminated with 15 W/cm(2) of the 514.5 nm laser line at room temperature. The amount of hydrogen that diffuses out of the a-Si:H layer is estimated semiquantitatively to be approximately 9x10(-4) at. %. (C) 2000 American Institute of Physics. [S0003-6951(00)02243-9]. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. Sogang Univ, Dept Phys, Seoul 121742, South Korea. RP Cheong, HM (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. RI Lee, Sehee/A-5989-2011; Cheong, Hyeonsik/D-7424-2012 OI Cheong, Hyeonsik/0000-0002-2347-4044 NR 9 TC 14 Z9 16 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 OCT 23 PY 2000 VL 77 IS 17 BP 2686 EP 2688 DI 10.1063/1.1320015 PG 3 WC Physics, Applied SC Physics GA 363ZQ UT WOS:000089867900020 ER PT J AU Chernyak, L Osinsky, A Nootz, G Schulte, A Jasinski, J Benamara, M Liliental-Weber, Z Look, DC Molnar, RJ AF Chernyak, L Osinsky, A Nootz, G Schulte, A Jasinski, J Benamara, M Liliental-Weber, Z Look, DC Molnar, RJ TI Electron beam and optical depth profiling of quasibulk GaN SO APPLIED PHYSICS LETTERS LA English DT Article ID DIFFUSION LENGTH; GALLIUM NITRIDE; RECOMBINATION; GROWTH; LAYER AB Electron beam and optical depth profiling of thick (5.5-64 mu m) quasibulk n-type GaN samples, grown by hydride vapor-phase epitaxy, were carried out using electron beam induced current (EBIC), microphotoluminescence (PL), and transmission electron microscopy (TEM). The minority carrier diffusion length, L, was found to increase linearly from 0.25 mu m, at a distance of about 5 mu m from the GaN/sapphire interface, to 0.63 mu m at the GaN surface, for a 36-mu m-thick sample. The increase in L was accompanied by a corresponding increase in PL band-to-band radiative transition intensity as a function of distance from the GaN/sapphire interface. We attribute the latter changes in PL intensity and minority carrier diffusion length to a reduced carrier mobility and lifetime at the interface, due to scattering at threading dislocations. The results of EBIC and PL measurements are in good agreement with the values for dislocation density obtained using TEM. (C) 2000 American Institute of Physics. [S0003-6951(00)00643-4]. C1 Univ Cent Florida, Dept Phys, Orlando, FL 32816 USA. Corning Appl Technol, Woburn, MA 01801 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Wright State Univ, Dayton, OH 45435 USA. USAF, Res Lab, Dayton, OH 45435 USA. MIT, Lincoln Lab, Lexington, MA 02173 USA. Univ Warsaw, Inst Expt Phys, PL-00681 Warsaw, Poland. RP Chernyak, L (reprint author), Univ Cent Florida, Dept Phys, Orlando, FL 32816 USA. RI Liliental-Weber, Zuzanna/H-8006-2012 NR 13 TC 46 Z9 46 U1 4 U2 21 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 OCT 23 PY 2000 VL 77 IS 17 BP 2695 EP 2697 DI 10.1063/1.1319530 PG 3 WC Physics, Applied SC Physics GA 363ZQ UT WOS:000089867900023 ER PT J AU Lewis, RM Wei, HP Lin, SY Klem, JF AF Lewis, RM Wei, HP Lin, SY Klem, JF TI Effects of prewells on transport in p-type resonant tunneling diodes SO APPLIED PHYSICS LETTERS LA English DT Article ID QUANTUM-WELLS; HOLES; GAAS; HETEROSTRUCTURES AB We investigate the transport of holes through AlAs/In0.10Ga0.90As resonant tunneling diodes which utilize InxGa1-xAs prewells in the emitter with x=0, 0.10, and 0.20. The data show an increase in peak current and bias at resonance and a concurrent increase in the peak-to-valley ratio with increasing x. We explain this enhancement in tunneling as due to confinement (or localization) of charges in the prewell and the formation of direct heavy (light) hole to heavy (light) hole conduction channels as a consequence. (C) 2000 American Institute of Physics. [S0003-6951(00)04443-0]. C1 Indiana Univ, Dept Phys, Bloomington, IN 47405 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Lewis, RM (reprint author), Indiana Univ, Dept Phys, Bloomington, IN 47405 USA. NR 12 TC 3 Z9 3 U1 0 U2 0 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 OCT 23 PY 2000 VL 77 IS 17 BP 2722 EP 2724 DI 10.1063/1.1320457 PG 3 WC Physics, Applied SC Physics GA 363ZQ UT WOS:000089867900032 ER PT J AU Tober, ED Marks, RF Chambliss, DD Roche, KP Toney, MF Kellock, AJ Farrow, RFC AF Tober, ED Marks, RF Chambliss, DD Roche, KP Toney, MF Kellock, AJ Farrow, RFC TI Magnetoresistance of self-assembled lateral multilayers SO APPLIED PHYSICS LETTERS LA English DT Article ID GIANT MAGNETORESISTANCE; ANISOTROPIC MAGNETORESISTANCE; IRON FILMS; DEPENDENCE; NANOWIRES; ALLOYS AB The angular-dependent magnetoresistance and magnetization of epitaxial FeetaAg1-eta self-assembled lateral multilayers (SALMs) grown on Mo(110)/Al2O3(11-2 0) template layers has been examined for an optimum stoichiometry of eta=0.38. The low-temperature anisotropic magnetoresistance (AMR) and low-field magnetoresistance (MR) are measured as a function of field angle for two nearly orthogonal current directions. The SALM structures are observed to display a significant AMR (roughly 1.6% maximum for the entire structure) and a pronounced field-dependent MR with a maximum Delta R/R of 0.88% at 2.7 K. (C) 2000 American Institute of Physics. [S0003-6951(00)02043-X]. C1 IBM Corp, Almaden Res Ctr, Div Res, San Jose, CA 95120 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Natl Ctr Electron Microscopy, Berkeley, CA 94720 USA. RP Tober, ED (reprint author), Nuance Commun, 1380 Willow Rd, Menlo Park, CA 94025 USA. RI Roche, Kevin/L-8504-2013 OI Roche, Kevin/0000-0001-8601-1525 NR 11 TC 14 Z9 14 U1 0 U2 4 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 OCT 23 PY 2000 VL 77 IS 17 BP 2728 EP 2730 DI 10.1063/1.1319514 PG 3 WC Physics, Applied SC Physics GA 363ZQ UT WOS:000089867900034 ER PT J AU Nelson, AJ Reynolds, JG Baumann, TF Fox, GA AF Nelson, AJ Reynolds, JG Baumann, TF Fox, GA TI X-ray photoemission investigation of binding sites in polymer-bound thiacrowns used for environmental remediation of Hg in aqueous solutions SO APPLIED SURFACE SCIENCE LA English DT Article DE X-ray photoemission; polymer-bound thiacrowns; Hg ID CROWN THIOETHER CHEMISTRY; METAL-COMPLEXES; FORMATION-CONSTANTS; MERCURY AB X-ray photoemission spectroscopy has been used to examine how Hg is bound to a polymer-bound thiacrown shown to be effective in extracting Hg-II from acidic aqueous solutions. High resolution Hg 4f and S 2p core-level spectra were acquired for a set of well-characterized sulfur-containing model compounds and their corresponding Hg complexes. Results from these materials were used to interpret the Hg 4f and S 2p core-level spectra of the polymer-bound thiacrown material, the thiacrown monomeric precursors and the Hg-containing reacted polymer. The thiacrown structure was found to be unaffected by incorporation into the polymer and Hg appears to be bound to the polymer complex in a similar manner as tig is bound in monomeric thiacrowns containing five sulfur atoms. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Calif Lawrence Livermore Natl Lab, Dept Chem & Mat Sci, Livermore, CA 94550 USA. RP Nelson, AJ (reprint author), Univ Calif Lawrence Livermore Natl Lab, Dept Chem & Mat Sci, Livermore, CA 94550 USA. NR 35 TC 17 Z9 17 U1 1 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0169-4332 J9 APPL SURF SCI JI Appl. Surf. Sci. PD OCT 23 PY 2000 VL 167 IS 3-4 BP 205 EP 215 DI 10.1016/S0169-4332(00)00523-7 PG 11 WC Chemistry, Physical; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Chemistry; Materials Science; Physics GA 358DT UT WOS:000089542500011 ER PT J AU Zhan, CG Wang, QL Xiong, Y Chen, X AF Zhan, CG Wang, QL Xiong, Y Chen, X TI Maximum bond order hybrid orbital calculations of C=O bond stretching vibrational frequencies SO JOURNAL OF MOLECULAR STRUCTURE-THEOCHEM LA English DT Article DE s-characters; C=O bond stretching; bond order; hybrid orbital ID SPIN COUPLING-CONSTANTS; MBOHO CALCULATIONS; CARBON; 1,4-BENZOQUINONE; COMPLEXES; SPECTRA; ATOMS; ANION AB A generalized relationship, which includes contributions of the s-characters of C=O bond and the net atomic charges, is employed to elucidate C=O bond stretching vibrational frequencies based on the maximum bond order hybrid orbital calculations at ab initio HF/6-31G* level of theory. It is demonstrated that the change of the s-characters is the most important factor for determining the change of C=O stretching frequencies. The C=O stretching frequencies calculated by using the explicit relationship obtained are in good agreement with the corresponding experimental frequencies. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Cent China Normal Univ, Dept Chem, Wuhan 430070, Peoples R China. RP Zhan, CG (reprint author), Battelle NW, Pacific NW Natl Lab, Mailstop K2-21, Richland, WA 99352 USA. NR 31 TC 2 Z9 2 U1 1 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0166-1280 J9 J MOL STRUC-THEOCHEM JI Theochem-J. Mol. Struct. PD OCT 23 PY 2000 VL 531 BP 33 EP 37 DI 10.1016/S0166-1280(00)00396-1 PG 5 WC Chemistry, Physical SC Chemistry GA 368GZ UT WOS:000090110500004 ER PT J AU Skurski, P Gutowski, M AF Skurski, P Gutowski, M TI Excited electronic states of the anion of 7,7,8,8-tetracyanoquinodimethane (TCNQ) SO JOURNAL OF MOLECULAR STRUCTURE-THEOCHEM LA English DT Article DE TCNQ(-); excited states; semi-empirical calculations; PM3 ID LASER PHOTOELECTRON SPECTROMETRY; PHOTODETACHMENT SPECTROSCOPY; SEMIEMPIRICAL METHODS; BINDING-ENERGIES; NEGATIVE-IONS; MONOVALENT; DIPOLE; TETRACYANOQUINODIMETHANE; OPTIMIZATION; TRANSITIONS AB The doublet and quarter anionic states of TCNQ have been studied at the configuration interaction (CI/PM3) level. Our results support an experimental claim from the Brauman group that not only the ground anionic state but also some excited states of TCNQ(-) are electronically stable. The core excited 1(2)B(3u) state is separated from the ground B-2(2g) anionic state by only 1.2 eV at the CI/PM3 level. Two externally excited (2)A(u) and 2(2)B(3u) anionic states are separated by ca. 2.3 eV from the ground B-2(2g) state and are close in energy to the ground electronic state of the neutral TCNQ. In addition, two quartet anionic states B-4(2g) and B-4(1g) are found to be electronically stable with respect to the lowest triplet B-3(1u) State of the neutral. All these anionic states have minima at D-2h geometries. Our results suggest that the 1(2)B(3u) <-- B-2(2g) and 2(2)B(3u) <-- B-2(2g) transitions contribute to the electronic absorption and electron photodetachment spectra of TCNQ(-). This conclusion is based on calculated values of electronic transition energies, oscillator strengths, and excess electron binding energies. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Utah, Dept Chem, Salt Lake City, UT 84112 USA. Univ Gdansk, Dept Chem, PL-80952 Gdansk, Poland. Pacific NW Natl Lab, Richland, WA 99352 USA. RP Gutowski, M (reprint author), Univ Utah, Dept Chem, Salt Lake City, UT 84112 USA. NR 58 TC 16 Z9 16 U1 0 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0166-1280 J9 J MOL STRUC-THEOCHEM JI Theochem-J. Mol. Struct. PD OCT 23 PY 2000 VL 531 BP 339 EP 348 DI 10.1016/S0166-1280(00)00467-X PG 10 WC Chemistry, Physical SC Chemistry GA 368GZ UT WOS:000090110500032 ER PT J AU Xie, JJ Chen, SP Brand, HV Rabie, RL AF Xie, JJ Chen, SP Brand, HV Rabie, RL TI High-pressure thermodynamic, electronic and magnetic properties of Ni SO JOURNAL OF PHYSICS-CONDENSED MATTER LA English DT Article ID THERMAL-EXPANSION; FIRST-PRINCIPLES; SEMICONDUCTORS; DIAMOND; SOLIDS; METALS; TRANSITION; SILVER; STATE AB The thermodynamic, electronic and magnetic properties of Ni at high pressures have been calculated using the ab initio pseudopotential plane-wave method and the density-functional theory. The P-V-T equation of state is obtained from the Helmholtz free energy of the crystal in the quasiharmonic approximation. The pressure dependence of the thermal expansion coefficient, bulk modulus, electronic band structure, phonon spectrum and the magnetic moment are presented. The calculated results are in good agreement with the available experiment measurements. C1 Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Univ Calif Los Alamos Natl Lab, Dynam Experimentat Div, Los Alamos, NM 87545 USA. RP Xie, JJ (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, POB 1663, Los Alamos, NM 87545 USA. NR 33 TC 20 Z9 20 U1 0 U2 4 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 OCT 23 PY 2000 VL 12 IS 42 BP 8953 EP 8962 DI 10.1088/0953-8984/12/42/302 PG 10 WC Physics, Condensed Matter SC Physics GA 369WR UT WOS:000165091200003 ER PT J AU Kalos, MH Pederiva, F AF Kalos, MH Pederiva, F TI Exact Monte Carlo method for continuum fermion systems SO PHYSICAL REVIEW LETTERS LA English DT Article ID FLUID; PAIRS AB We offer a new proposal for the Monte Carlo treatment of many-fermion systems in continuous space. It is based upon diffusion Monte Carlo with significant modifications: correlated pairs of random walkers that carry opposite signs, different functions "guide" walkers of different signs, the Gaussians used for members of a pair are correlated, and walkers can cancel so as to conserve their expected future contributions. We report results for free-fermion systems and a fermion fluid with 14 He-3 atoms, where it proves stable and correct. Its computational complexity grows with particle number, but slowly enough to make interesting physics within the reach of contemporary computers. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Trent, Dipartimento Fis, I-38050 Trent, Italy. RP Kalos, MH (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 5508, Livermore, CA 94550 USA. NR 16 TC 30 Z9 30 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 OCT 23 PY 2000 VL 85 IS 17 BP 3547 EP 3551 DI 10.1103/PhysRevLett.85.3547 PG 5 WC Physics, Multidisciplinary SC Physics GA 366GN UT WOS:000089996600001 ER PT J AU Beacom, JF Boyd, RN Mezzacappa, A AF Beacom, JF Boyd, RN Mezzacappa, A TI Technique for direct eV-scale measurements of the mu and tau neutrino masses using supernova neutrinos SO PHYSICAL REVIEW LETTERS LA English DT Article ID TRITIUM BETA-SPECTRUM; UPPER LIMIT; WEIGHING NEUTRINOS; NU(TAU) NEUTRINOS; SIGNATURE; NU(MU) AB Early black hole formation in a Core-collapse supernova will abruptly truncate the neutrino fluxes. The sharp cutoff can be used to make model-independent time-of-flight neutrino mass tests. assuming a neutrino luminosity of 10(52) erg/s per flavor at cutoff and a distance of 10 kpc, Super-Kamiokande can detect an electron neutrino mass as small as 1.8 eV, and the proposed OMNIS detector can detect mu and tau neutrino masses as small as 6 eV. We present the first technique with direct sensitivity to eV-scale mu and tau neutrino masses. C1 Ohio State Univ, Dept Phys & Astron, Columbus, OH 43210 USA. Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. CALTECH, Dept Phys 161 33, Pasadena, CA 91125 USA. RP Fermilab Natl Accelerator Lab, MS-209,POB 500, Batavia, IL 60510 USA. EM beacom@fnal.gov; boyd@mps.ohio-state.edu; mezz@nova.phy.ornl.gov RI Mezzacappa, Anthony/B-3163-2017; OI Mezzacappa, Anthony/0000-0001-9816-9741; Beacom, John/0000-0002-0005-2631 NR 27 TC 43 Z9 44 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 EI 1079-7114 J9 PHYS REV LETT JI Phys. Rev. Lett. PD OCT 23 PY 2000 VL 85 IS 17 BP 3568 EP 3571 DI 10.1103/PhysRevLett.85.3568 PG 4 WC Physics, Multidisciplinary SC Physics GA 366GN UT WOS:000089996600006 ER PT J AU Guo, XF Wang, XN AF Guo, XF Wang, XN TI Multiple scattering, parton energy loss, and modified fragmentation functions in deeply inelastic eA scattering SO PHYSICAL REVIEW LETTERS LA English DT Article ID HEAVY-ION COLLISIONS; TRANSVERSE-MOMENTUM; HADRONIC SCATTERING; NUCLEAR-DEPENDENCE; POWER CORRECTIONS; QCD AB Modified quark fragmentation functions in deeply inelastic eA collisions and their QCD evolution equations are derived for the first time in the framework of multiple parton scattering. Induced radiation gives rise to additional terms in the evolution equations and thus softens the modified quark fragmentation functions. The results in the next-leading-twist depend on both diagonal and off-diagonal twist-four parton distributions and the combination of which clearly manifests the LPM interference pattern. The predicted modification depends quadratically on the nuclear size (A(2/3)). Generalization to the case of hot QCD medium is also discussed. C1 Univ Kentucky, Dept Phys & Astron, Lexington, KY 40506 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. RP Guo, XF (reprint author), Univ Kentucky, Dept Phys & Astron, Lexington, KY 40506 USA. OI Wang, Xin-Nian/0000-0002-9734-9967 NR 29 TC 237 Z9 239 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 OCT 23 PY 2000 VL 85 IS 17 BP 3591 EP 3594 DI 10.1103/PhysRevLett.85.3591 PG 4 WC Physics, Multidisciplinary SC Physics GA 366GN UT WOS:000089996600012 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 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 Good, 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, A 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 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 Good, 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, A Voros, S Wyslouch, B Yagi, K Yokota, Y Young, GR CA WA98 Collaboration TI Observation of direct photons in central 158A GeV Pb-208+Pb-208 collisions SO PHYSICAL REVIEW LETTERS LA English DT Article ID QUARK-GLUON PLASMA; PHASE-TRANSITION; S+AU COLLISIONS; HADRON; SINGLE; 200-GEV/C; SPECTRA; MATTER AB A measurement of direct photon production in Pb-208 + Pb-208 collisions at 158A GeV has been carried out in the CERN WA98 experiment. The invariant yield of direct photons in central collisions is extracted as a function of transverse momentum in the interval 0.5 < p(T) < 4 GeV/c. A significant direct photon signal, compared to statistical and systematical errors, is seen at p(T) > 1.5 GeV/c. The result constitutes the first observation of direct photons in ultrarelativistic heavy-ion collisions. It could be significant for diagnosis;of quark-gluon-plasma formation. C1 Panjab Univ, Chandigarh 160014, India. Univ Rajasthan, Jaipur 302004, Rajasthan, India. Bhabha Atom Res Ctr, Ctr Variable Energy Cyclotron, Calcutta 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. GSI Darmstadt, Gesell Schwerionenforsch GmbH, D-64220 Darmstadt, Germany. Univ Utrecht, NIKHEF, NL-3508 TA Utrecht, Netherlands. Univ Lund, SE-22100 Lund, Sweden. Univ Tsukuba, Tsukuba, Ibaraki 305, Japan. Inst Nucl Phys, 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 37996 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 26 TC 158 Z9 158 U1 0 U2 6 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD OCT 23 PY 2000 VL 85 IS 17 BP 3595 EP 3599 DI 10.1103/PhysRevLett.85.3595 PG 5 WC Physics, Multidisciplinary SC Physics GA 366GN UT WOS:000089996600013 ER PT J AU Hoyt, CW Sheik-Bahae, M Epstein, RI Edwards, BC Anderson, JE AF Hoyt, CW Sheik-Bahae, M Epstein, RI Edwards, BC Anderson, JE TI Observation of anti-Stokes fluorescence cooling in thulium-doped glass SO PHYSICAL REVIEW LETTERS LA English DT Article ID FLUOROZIRCONATE FIBER; UP-CONVERSION; LASER AB We report the first observation of anti-Stokes fluorescence cooling in a thulium-doped solid with pump excitation at 1.82 mum < < 1-97 m. At a pump wavelength of 1.9 mum and incident average power of similar to3 W, a Tm3+:ZBLANP (ZrF4-BaF2-LaF3-AlF3-NaF-PbF2) sample cooled to -1.2 degreesC from room temperature for a single pass of the pump beam. This corresponds to an absorbed pump power of similar to 40 mW and a peak temperature change per absorbed power of similar to -30 degreesC/W from room temperature. C1 Univ New Mexico, Dept Phys & Astron, Albuquerque, NM 87131 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Hoyt, CW (reprint author), Univ New Mexico, Dept Phys & Astron, Albuquerque, NM 87131 USA. NR 12 TC 143 Z9 151 U1 4 U2 24 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD OCT 23 PY 2000 VL 85 IS 17 BP 3600 EP 3603 DI 10.1103/PhysRevLett.85.3600 PG 4 WC Physics, Multidisciplinary SC Physics GA 366GN UT WOS:000089996600014 ER PT J AU Zweiback, J Cowan, TE Smith, RA Hartley, JH Howell, R Steinke, CA Hays, G Wharton, KB Crane, JK Ditmire, T AF Zweiback, J Cowan, TE Smith, RA Hartley, JH Howell, R Steinke, CA Hays, G Wharton, KB Crane, JK Ditmire, T TI Characterization of fusion burn time in exploding deuterium cluster plasmas SO PHYSICAL REVIEW LETTERS LA English DT Article ID NEUTRON; EXPLOSIONS; DYNAMICS AB Exploiting the energetic interaction of intense femtosecond laser pulses with deuterium clusters, it is possible to create conditions in which nuclear fusion results from explosions of these clusters. We have conducted high-resolution neutron time-of-flight spectroscopy on these plasmas and show that they yield fast bursts of nearly monochromatic fusion neutrons with temporal duration as short as a few hundred picoseconds. Such a short, nearly pointlike source now opens up the unique possibility of using these bright neutron pulses, either as a pump or a probe, to conduct ultrafast studies with neutrons. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ London Imperial Coll Sci Technol & Med, London SW7, England. Harvard Univ, Cambridge, MA 02138 USA. RP Ditmire, T (reprint author), Univ Calif Lawrence Livermore Natl Lab, L-477, Livermore, CA 94550 USA. RI Cowan, Thomas/A-8713-2011 OI Cowan, Thomas/0000-0002-5845-000X NR 18 TC 135 Z9 138 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 OCT 23 PY 2000 VL 85 IS 17 BP 3640 EP 3643 DI 10.1103/PhysRevLett.85.3640 PG 4 WC Physics, Multidisciplinary SC Physics GA 366GN UT WOS:000089996600024 ER PT J AU Qin, XR Swartzentruber, BS Lagally, MG AF Qin, XR Swartzentruber, BS Lagally, MG TI Diffusional kinetics of SiGe dimers on Si(100) using atom-tracking scanning tunneling microscopy SO PHYSICAL REVIEW LETTERS LA English DT Article ID AD-DIMERS; SI(001); SURFACE AB Quantitative measurements of the diffusion of adsorbed mixed Ce-Si dimers on the Si(100) surface have been made as a function of temperature using atom-tracking scanning tunneling microscopy. These mixed dimers are distinguishable from pure Si-Si dimers by their characteristic kinetics-a 180 degrees rotation between two highly buckled configurations. At temperatures at which the mixed dimers diffuse, atomic-exchange events occur, in which the Ge atom in the adsorbed dimer exchanges with a substrate Si atom. Reexchange can also occur when the diffusing Si-Si dimer revisits the original site of exchange. C1 Univ Wisconsin, Madison, WI 53706 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Qin, XR (reprint author), Univ Wisconsin, Madison, WI 53706 USA. NR 13 TC 60 Z9 60 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 OCT 23 PY 2000 VL 85 IS 17 BP 3660 EP 3663 DI 10.1103/PhysRevLett.85.3660 PG 4 WC Physics, Multidisciplinary SC Physics GA 366GN UT WOS:000089996600029 ER PT J AU Kendig, LP Rek, ZU Yalisove, SM Bilello, JC AF Kendig, LP Rek, ZU Yalisove, SM Bilello, JC TI The role of impurities and microstructure on residual stress in nanoscale Mo films SO SURFACE & COATINGS TECHNOLOGY LA English DT Article DE thin films; molybdenum; residual stress; impurities ID SPUTTERED THIN-FILMS; INTRINSIC STRESS; MOLYBDENUM; TUNGSTEN; RESISTIVITY; GROWTH AB The residual stress varied substantially as a function of thickness in a series of 2.5 to 500 nm thick Mo films. Films were sputter deposited onto Si wafers with native oxide, and the residual stress was measured using double crystal diffraction topography (DCDT). The thinnest films had a high compressive stress on the order of 2 to 3 GPa and the stress relaxed with increasing film thickness. The coatings were examined using advanced characterization techniques such as Auger electron spectroscopy (AES), grazing incidence X-ray scattering (GIXS), and high-resolution transmission electron microscopy (HRTEM). AES showed the presence of O and C contamination at the interface between the substrate and the film. GIXS analysis of the Mo films showed that the lattice of the thinnest layers was considerably expanded compared to the interplanar spacing of bulk Mo, suggesting that impurities were incorporated into these films. HRTEM data suggested that the films interacted with only the adsorbed impurities and the top one or two layers of the native SiO2 layer. Molybdenum films deposited onto clean W layers were tensile, which supported the hypothesis that impurities caused the high compressive stresses in the films deposited onto SiO2. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Michigan, Dept Mat Sci & Engn, Ann Arbor, MI 48109 USA. Stanford Synchrotron Radiat Lab, Stanford, CA 94309 USA. RP 1897 N Cent Dr, Beavercreek, OH 45432 USA. EM kkendig@juno.com NR 23 TC 11 Z9 12 U1 0 U2 15 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0257-8972 J9 SURF COAT TECH JI Surf. Coat. Technol. PD OCT 23 PY 2000 VL 132 IS 2-3 BP 124 EP 129 DI 10.1016/S0257-8972(00)00908-7 PG 6 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 377VR UT WOS:000165547400004 ER PT J AU Krylov, AI Sherrill, CD Head-Gordon, M AF Krylov, AI Sherrill, CD Head-Gordon, M TI Excited states theory for optimized orbitals and valence optimized orbitals coupled-cluster doubles models SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID FULL CONFIGURATION-INTERACTION; 2ND-ORDER PERTURBATION-THEORY; POTENTIAL-ENERGY SURFACES; HARTREE-FOCK THEORY; DOUBLE-ZETA BASIS; EXCITATION-ENERGIES; RESPONSE FUNCTIONS; WAVE-FUNCTIONS; MOLECULAR APPLICATIONS; LINEAR RESPONSE AB We introduce an excited state theory for the optimized orbital coupled cluster doubles (OO-CCD) and valence optimized orbital coupled cluster doubles (VOO-CCD) models. The equations for transition energies are derived using a similarity transformed Hamiltonian. The effects of orbital relaxation are discussed. We present results for several single-reference molecules (H2O, CH2O, C2H4O, C2H4, BeO), as well as for molecules with significant nondynamical correlation in the ground state (CH+, BH, (A) over tilde (1)A(1) CH2), and for rectangular O-4(+). We find that: (i) OO-CCD excitation energies are very close to CCSD excitation energies; (ii) similarly to the complete active space SCF (CASSCF) model, the effects of orbital relaxation are very important for VOO-CCD excited states such that the excitation energies calculated by VOO-CCD and CASSCF with orbitals optimized for the ground state are very close to each other and unsatisfactory; (iii) the VOO-CCD model with an approximate treatment of orbital relaxation describes singly (valence and Rydberg) and doubly (valence) excited states within errors of 0.2-1.0 eV at equilibrium geometries and along bond-breaking coordinates; (iv) the above accuracy of the VOO-CCD model does not degrade as molecules or basis sets grow in size; (v) the shapes of potential energy surfaces around excited states minima are reproduced well by VOO-CCD model suggesting the use of this method for excited states geometry optimization. (C) 2000 American Institute of Physics. [S0021-9606(00)30540-2]. C1 Univ So Calif, Dept Chem, Los Angeles, CA 90089 USA. Georgia Inst Technol, Sch Chem & Biochem, Atlanta, GA 30332 USA. Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA. RP Univ So Calif, Dept Chem, Los Angeles, CA 90089 USA. OI Sherrill, David/0000-0002-5570-7666 NR 92 TC 102 Z9 102 U1 2 U2 11 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 OCT 22 PY 2000 VL 113 IS 16 BP 6509 EP 6527 AR PII [S0021-9606(00)30540-2] DI 10.1063/1.1311292 PG 19 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 368RL UT WOS:000090131300005 ER PT J AU Mas, EM Bukowski, R Szalewicz, K Groenenboom, GC Wormer, PES van der Avoird, A AF Mas, EM Bukowski, R Szalewicz, K Groenenboom, GC Wormer, PES van der Avoird, A TI Water pair potential of near spectroscopic accuracy. I. Analysis of potential surface and virial coefficients SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID ADAPTED PERTURBATION-THEORY; FULL CONFIGURATION-INTERACTION; MANY-BODY THEORY; AB-INITIO; INTERMOLECULAR INTERACTIONS; VANDERWAALS COEFFICIENTS; MOLECULAR INTERACTIONS; INTERACTION ENERGY; DENSITY-MATRIX; LIQUID WATER AB A new ab initio pair potential for water was generated by fitting 2510 interaction energies computed by the use of symmetry-adapted perturbation theory (SAPT). The new site-site functional form, named SAPT-5s, is simple enough to be applied in molecular simulations of condensed phases and at the same time reproduces the computed points with accuracy exceeding that of the elaborate SAPT-pp functional form used earlier [J. Chem. Phys. 107, 4207 (1997)]. SAPT-5s has been shown to quantitatively predict the water dimer spectra, see the following paper (paper II). It also gives the second virial coefficient in excellent agreement with experiment. Features of the water dimer potential energy surface have been analyzed using SAPT-5s. Average values of powers of the intermolecular separation-obtained from the ground-state rovibrational wave function computed in the SAPT-5s potential-have been combined with measured values to obtain a new empirical estimate of the equilibrium O-O separation equal to 5.50 +/-0.01 bohr, significantly shorter than the previously accepted value. The residual errors in the SAPT-5s potential have been estimated by comparison to recent large-scale extrapolated ab initio calculations for water dimer. This estimate-together with the dissociation energy D-0 computed from SAPT-5s-leads to a new prediction of the limit value of D-0 equal to 1165 +/- 54 cm(-1), close to but significantly more accurate than the best empirical value. (C) 2000 American Institute of Physics. [S0021-9606(00)30140-4]. C1 Univ Delaware, Dept Phys & Astron, Newark, DE 19716 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Warsaw Univ, Dept Chem, Quantum Chem Lab, PL-02093 Warsaw, Poland. Univ Nijmegen, NSR Ctr, Inst Theoret Chem, NL-6525 ED Nijmegen, Netherlands. RP Mas, EM (reprint author), Univ Delaware, Dept Phys & Astron, Newark, DE 19716 USA. RI Groenenboom, Gerrit/F-9692-2015; OI Groenenboom, Gerrit/0000-0002-0920-3707 NR 63 TC 136 Z9 136 U1 0 U2 16 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 OCT 22 PY 2000 VL 113 IS 16 BP 6687 EP 6701 AR PII [S0021-9606(00)30140-4] DI 10.1063/1.1311289 PG 15 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 368RL UT WOS:000090131300027 ER PT J AU Groenenboom, GC Wormer, PES van der Avoird, A Mas, EM Bukowski, R Szalewicz, K AF Groenenboom, GC Wormer, PES van der Avoird, A Mas, EM Bukowski, R Szalewicz, K TI Water pair potential of near spectroscopic accuracy. II. Vibration-rotation-tunneling levels of the water dimer SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID TERAHERTZ LASER SPECTROSCOPY; COUPLED 6-DIMENSIONAL CALCULATIONS; DISCRETE VARIABLE REPRESENTATION; INTERMOLECULAR BOUND-STATES; MATRIX KOHN METHOD; LIQUID WATER; QUANTITATIVE CHARACTERIZATION; INFRARED-SPECTROSCOPY; THEORETICAL-ANALYSIS; REACTIVE SCATTERING AB Nearly exact six-dimensional quantum calculations of the vibration-rotation-tunneling (VRT) levels of the water dimer for values of the rotational quantum numbers J and K less than or equal to2 show that the SAPT-5s water pair potential presented in the preceding paper (paper I) gives a good representation of the experimental high-resolution far-infrared spectrum of the water dimer. After analyzing the sensitivity of the transition frequencies with respect to the linear parameters in the potential we could further improve this potential by using only one of the experimentally determined tunneling splittings of the ground state in (H2O)(2). The accuracy of the resulting water pair potential, SAPT-5st, is established by comparison with the spectroscopic data of both (H2O)(2) and (D2O)(2): ground and excited state tunneling splittings and rotational constants, as well as the frequencies of the intermolecular vibrations. (C) 2000 American Institute of Physics. [S0021-9606(00)30240-9]. C1 Univ Nijmegen, NSR Ctr, Inst Theoret Chem, NL-6525 ED Nijmegen, Netherlands. Univ Delaware, Dept Phys & Astron, Newark, DE 19716 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Warsaw Univ, Dept Chem, Quantum Chem Lab, PL-02093 Warsaw, Poland. RP Groenenboom, GC (reprint author), Univ Nijmegen, NSR Ctr, Inst Theoret Chem, NL-6525 ED Nijmegen, Netherlands. RI Groenenboom, Gerrit/F-9692-2015; OI Groenenboom, Gerrit/0000-0002-0920-3707 NR 71 TC 87 Z9 87 U1 2 U2 12 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 OCT 22 PY 2000 VL 113 IS 16 BP 6702 EP 6715 DI 10.1063/1.1311290 PG 14 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 368RL UT WOS:000090131300028 ER PT J AU McMahon, BH Stojkovic, BP Hay, PJ Martin, RL Garcia, AE AF McMahon, BH Stojkovic, BP Hay, PJ Martin, RL Garcia, AE TI Microscopic model of carbon monoxide binding to myoglobin SO JOURNAL OF CHEMICAL PHYSICS LA English DT Review ID DENSITY-FUNCTIONAL THEORY; PHOTOSYNTHETIC REACTION-CENTER; FREE-ENERGY CALCULATIONS; INDUCED STRUCTURAL-CHANGES; O VIBRATIONAL FREQUENCIES; HISTOGRAM ANALYSIS METHOD; IRON-PORPHYRIN COMPLEXES; SPERM WHALE MYOGLOBIN; SOLID-STATE NMR; X-RAY STRUCTURE AB We present a microscopic model of carbon monoxide (CO) binding to myoglobin which reproduces the experimentally observed Arrhenius pre-exponential factor of 10(9) s(-1) and activation enthalpy distribution centered at 12 kJ/mol. The model is based on extensive ab initio calculations of CO interacting with a model heme-imidazole group which we performed using a fully quantum mechanical Hartree-Fock/density functional theory (HF/DFT) hybrid method. We fit the HF/DFT calculated energies, obtained for over 1000 heme-CO structures with varied CO and iron positions and orientations for both high (S=2) and low (S=0) spin states, to a model potential function which includes a bonding interaction in both of the spin states, electrostatic, and anisotropic Lennard-Jones-type interactions. By combining the x-ray determined protein structure with this potential and protein-CO interactions and internal heme interaction potentials obtained from established molecular dynamics literature, we calculate the energy required for the CO to reach the spin crossing from the heme pocket. We find that the transition between the two spin states occurs when CO and iron have activation enthalpies of 8 kJ/mol and 3 kJ/mol, respectively, which are necessary to move CO towards the iron and the iron atom relative to the heme plane N-pyr. At the same time we find that 1 kJ/mol is needed to move N-epsilon of His-64 and C-gamma of Val-68 relative to the heme group. The requirement that these motions be synchronized reduces the Arrhenius pre-exponential by a factor of 150 from the 10(12) s(-1) obtained from CO motion across the heme pocket, leaving a factor of similar to 6 to account for CO orientation and nonadiabaticity of the electronic spin change. The observed width of the enthalpy distribution is reproduced by assuming a Gaussian distribution of the heme positions with a standard deviation of 0.2 Angstrom. We characterize the conformational relaxation by calculating an enthalpy barrier using x-ray structures of myoglobin in both the MbCO photoproduct and deoxy conformations, and we find a small difference, similar to 5 kJ/mol, between the two conformations. (C) 2000 American Institute of Physics. [S0021-9606(00)01239-3]. C1 Los Alamos Natl Lab, Ctr Nonlinear Studies, Los Alamos, NM 87545 USA. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Los Alamos Natl Lab, Ctr Nonlinear Studies, Los Alamos, NM 87545 USA. NR 126 TC 67 Z9 68 U1 1 U2 9 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 OCT 22 PY 2000 VL 113 IS 16 BP 6831 EP 6850 AR PII [S0021-9606(00)01239-3] DI 10.1063/1.1309524 PG 20 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 368RL UT WOS:000090131300041 ER PT J AU Handler, G Arentoft, T Shobbrook, RR Wood, MA Crause, LA Crake, P Podmore, F Habanyama, A Oswalt, T Birch, PV Lowe, G Sterken, C Meintjes, P Brink, J Claver, CF Medupe, R Guzik, JA Beach, TE Martinez, P Leibowitz, EM Ibbetson, PA Smith, T Ashoka, BN Raj, NE Kurtz, DW Balona, LA O'Donoghue, D Costa, JES Breger, M AF Handler, G Arentoft, T Shobbrook, RR Wood, MA Crause, LA Crake, P Podmore, F Habanyama, A Oswalt, T Birch, PV Lowe, G Sterken, C Meintjes, P Brink, J Claver, CF Medupe, R Guzik, JA Beach, TE Martinez, P Leibowitz, EM Ibbetson, PA Smith, T Ashoka, BN Raj, NE Kurtz, DW Balona, LA O'Donoghue, D Costa, JES Breger, M TI Delta Scuti Network observations of XX Pyx: detection of 22 pulsation modes and of short-term amplitude and frequency variations SO MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY LA English DT Article DE techniques : photometric; stars : individual : CD-24 7599; stars : individual : XX Pyx; stars : oscillations; delta Scuti ID ASTRONOMICAL TIME-SERIES; WHOLE-EARTH-TELESCOPE; NONRADIAL PULSATION; STAR; PHOTOMETRY; ASTEROSEISMOLOGY; PRAESEPE AB We report multisite observations devoted to the main-sequence delta Scuti star XX Pyx, conducted as the l7th run of the Delta Scuti Network. Over 125 nights a total of 550 h of usable time-series photometric B- and V-filter data were acquired involving both photoelectric and CCD measurements at eight observatories spread around the world, which represents the most extensive single time-series for any pulsating star other than the Sun obtained so far. We describe our observations and reduction methods, and present the frequency analysis of our new data. First, we detect six new pulsation and five new combination frequencies in the star's light curves. We also discover evidence for amplitude and/or frequency variations of some of the modes during the observations. These can occur on time-scales as short as 20 d and show quite diverse behaviour. To take them into account in the frequency analysis, a so-called non-linear frequency analysis method was developed, allowing us to quantify the temporal variability of the modes and to compensate for it. Following that we continue the frequency search and we also incorporate published multisite observations. In this way, we reveal three more pulsation and two more combination frequencies. In the end, we report a total of 30 significant frequencies - 22 of which correspond to independent pulsation modes. This is the largest number of independent modes ever detected in the light curves of a delta Scuti star. C1 Univ Vienna, Inst Astron, A-1180 Vienna, Austria. S African Astron Observ, ZA-7935 Cape Town, South Africa. Free Univ Brussels, B-1050 Brussels, Belgium. Australian Natl Univ, Res Sch Astron & Astrophys, Weston Creek, ACT 2611, Australia. Florida Inst Technol, Dept Phys & Space Sci, Melbourne, FL 32901 USA. Florida Inst Technol, SARA Observ, Melbourne, FL 32901 USA. Univ Cape Town, Dept Astron, ZA-7700 Rondebosch, South Africa. Perth Observ, Bickley, WA 6076, Australia. Univ Zimbabwe, Dept Phys, Harare, Zimbabwe. Univ Zambia, Dept Phys, Lusaka, Zambia. Univ Orange Free State, Dept Phys, ZA-9300 Bloemfontein, South Africa. Natl Opt Astron Observ, Tucson, AZ 85726 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ New Mexico, Dept Nat Sci, Los Alamos, NM 87544 USA. Tel Aviv Univ, Sackler Fac Exact Sci, Wise Observ, IL-69978 Tel Aviv, Israel. Indian Space Res Org, Tech Phys Div, ISRO, Satellite Ctr, Bangalore 560017, Karnataka, India. Univ Fed Rio Grande Sul, Inst Fis, BR-91501970 Porto Alegre, RS, Brazil. RP Handler, G (reprint author), Univ Vienna, Inst Astron, Turkenschanzstr 17, A-1180 Vienna, Austria. NR 31 TC 58 Z9 59 U1 0 U2 0 PU BLACKWELL SCIENCE LTD PI OXFORD PA P O BOX 88, OSNEY MEAD, OXFORD OX2 0NE, OXON, ENGLAND SN 0035-8711 J9 MON NOT R ASTRON SOC JI Mon. Not. Roy. Astron. Soc. PD OCT 21 PY 2000 VL 318 IS 2 BP 511 EP 525 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 374BT UT WOS:000165325100023 ER PT J AU Rosenberg, RA Harkay, KC AF Rosenberg, RA Harkay, KC TI A rudimentary electron energy analyzer for accelerator diagnostics SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article DE electron analyzer; accelerator; diagnostics ID BEAM AB We have constructed a compact, planar retarding field analyzer for the diagnostics of low-energy background electrons in a high-energy particle accelerator. Bench measurements of the analyzer have been made to characterize it, and the results are reasonable in light of models of this type of analyzer. Comparisons to results obtained using a beam-position monitor (BPM) show the advantages of this analyzer for electron diagnostics. Sample results from analyzers installed at the Advanced Photon Source storage ring at Argonne National Laboratory and the Proton Storage Ring at Los Alamos National Laboratory show how the analyzers can be used for studying the intensity, energy, and time structure of electrons in an accelerator environment. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. RP Rosenberg, RA (reprint author), Argonne Natl Lab, Adv Photon Source, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Rosenberg, Richard/K-3442-2012 NR 10 TC 38 Z9 39 U1 0 U2 3 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 OCT 21 PY 2000 VL 453 IS 3 BP 507 EP 513 DI 10.1016/S0168-9002(00)00472-1 PG 7 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 367VV UT WOS:000090082900003 ER PT J AU Lindback, S Karlsson, AC Mittler, J Blaxhult, A Carlsson, M Briheim, G Sonnerborg, A Gaines, H AF Lindback, S Karlsson, AC Mittler, J Blaxhult, A Carlsson, M Briheim, G Sonnerborg, A Gaines, H CA Karolinska Institutet Primary HIV TI Viral dynamics in primary HIV-1 infection SO AIDS LA English DT Article DE primary HIV-1 infection; HIV-RNA; treatment ID HUMAN-IMMUNODEFICIENCY-VIRUS; CD4(+) T-CELLS; TYPE-1 INFECTION; ANTIRETROVIRAL THERAPY; SEXUAL TRANSMISSION; VIREMIA; PLASMA; LYMPHOCYTES; RESPONSES; SEROCONVERSION AB Objectives: To study the natural course of viremia during primary HIV infection (PHI). Method: Eight patients were followed from a median of 5 days from the onset of PHI illness. Plasma HIV-1 RNA levels were measured frequently and the results were fitted to mathematical models. HIV-1 RNA levels were also monitored in nine patients given two reverse transcriptase inhibitors and a protease inhibitor after a median of 7 days from the onset of Pi-II illness. Results: HIV-1 RNA appeared in the blood during the week preceding onset of PHI illness and increased rapidly during the first viremic phase, reaching a peak at a mean of 7 days after onset of illness. This was followed by a phase of rapidly decreasing levels of HIV-1 RNA to an average of 21 days after onset. Viral density continued to decline thereafter but at a 5- to 50-fold lower rate; a steady-state level was reached at a median of 2 months after onset of PHI. Peak viral density levels correlated significantly with levels measured between days 50 and 600. Initiation of antiretroviral treatment during PHI resulted in rapidly declining levels to below 50 copies/ml. Conclusions: This study demonstrates the kinetic phases of viremia during PHI and indicates two new contributions to the natural history of HIV-1 infection: PHI peak levels correlate with steady-state levels and HIV-1 RNA declines biphasically; an initial rapid decay is usually followed by a slow decay, which is similar to the initial changes seen with antiviral treatment. (C) 2000 Lippincott Williams & Wilkins. C1 Swedish Inst Infect Dis Control, S-17182 Solna, Sweden. Karolinska Hosp, Karolinska Inst, Dept Infect Dis, Solna, Sweden. Huddinge Univ Hosp, Karolinska Inst, Dept Infect Dis, S-14186 Huddinge, Sweden. Huddinge Univ Hosp, Karolinska Inst, Div Clin Virol, S-14186 Huddinge, Sweden. Jonkoping Hosp, Dept Infect Dis, Jonkoping, Sweden. Linkoping Univ Hosp, Dept Infect Dis, S-58185 Linkoping, Sweden. Univ Calif Los Alamos Natl Lab, Theoret Biol & Biophys Grp T10, Los Alamos, NM USA. Univ Washington, Dept Microbiol, Seattle, WA 98195 USA. RP Gaines, H (reprint author), Swedish Inst Infect Dis Control, S-17182 Solna, Sweden. RI Karlsson, Annika/R-2255-2016 OI Karlsson, Annika/0000-0002-2028-8393 NR 34 TC 79 Z9 80 U1 0 U2 4 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0269-9370 J9 AIDS JI Aids PD OCT 20 PY 2000 VL 14 IS 15 BP 2283 EP 2291 DI 10.1097/00002030-200010200-00009 PG 9 WC Immunology; Infectious Diseases; Virology SC Immunology; Infectious Diseases; Virology GA 371AL UT WOS:000165155400008 PM 11089616 ER PT J AU Schlamp, S Hornung, HG Sobota, TH Cummings, EB AF Schlamp, S Hornung, HG Sobota, TH Cummings, EB TI Accuracy and uncertainty of single-shot, nonresonant laser-induced thermal acoustics SO APPLIED OPTICS LA English DT Article AB We study the accuracy and uncertainty of single-shot nonresonant laser-induced thermal acoustics measurements of the speed of sound and the thermal diffusivity in unseeded atmospheric air from electrostrictive gratings as a function of the laser power settings. For low pump energies, the measured speed of sound is too low, which is due to the influence of noise on the numerical data analysis scheme. For pump energies comparable to and higher than the breakdown energy of the gas, the measured speed of sound is too high. This is an effect of leaving the acoustic limit, and instead creating finite-amplitude density perturbations. The measured thermal diffusivity is too large for high noise levels but it decreases below the predicted value for high pump energies. The pump energy where the error is minimal coincides for the speed of sound and for the thermal diffusivity measurements. The errors at this minimum are 0.03% and 1%, respectively. The uncertainties for the speed of sound and the thermal diffusivity decrease monotonically with signal intensity to 0.25% and 5%, respectively. (C) 2000 Optical Society of America OCIS codes: 000.2170, 050.2770, 120.6780, 190.4380. C1 CALTECH, Aeronaut Lab, Pasadena, CA 91125 USA. Adv Projects Res Inc, La Verne, CA 91750 USA. Sandia Natl Labs, Livermore, CA 94551 USA. RP Schlamp, S (reprint author), CALTECH, Aeronaut Lab, Pasadena, CA 91125 USA. EM stefan@galcit.caltech.edu; hans@galcit.caltech.edu; thsobota@advancedprojects.com; labsmith@home.com RI Schlamp, Stefan/A-9143-2008 OI Schlamp, Stefan/0000-0002-9933-3096 NR 10 TC 6 Z9 6 U1 0 U2 2 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1559-128X EI 2155-3165 J9 APPL OPTICS JI Appl. Optics PD OCT 20 PY 2000 VL 39 IS 30 BP 5477 EP 5481 DI 10.1364/AO.39.005477 PG 5 WC Optics SC Optics GA 364ZV UT WOS:000089924700008 PM 18354543 ER PT J AU Nortershauser, W Bushaw, BA Muller, P Wendt, K AF Nortershauser, W Bushaw, BA Muller, P Wendt, K TI Line shapes in triple-resonance ionization spectroscopy SO APPLIED OPTICS LA English DT Article ID MASS-SPECTROMETRY; ENVIRONMENTAL-SAMPLES; TRACE ANALYSIS; CA-41; CALCIUM; LASERS; DIODE; SR-90 AB Line shapes in high-resolution triple-resonance ionization spectroscopy have been calculated and compared with experimental measurements on the 4s(2) S-1(0)-->4s4p P-1(1)-->4s4d(1)D(2)-->4snf(1)F(3)-->Ca+ system of calcium. Calculations based on the density matrix formalism integrated the fundamental equations over experimental atomic angular and velocity distributions and laser intensity profiles. The measurements reveal and confirm all predicted structures arising from the complex coupling of four atomic states with three laser fields and the Doppler distribution of the atomic ensemble. Effects of different laser beam geometries on the line shapes have been investigated. The agreement between calculated and experimental spectra is generally good over a dynamic range of 10 orders of magnitude. Thus these calculations can accurately predict optical isotopic selectivity in multistep resonance ionization, with a value of S-opt similar to 10(10) expected for detection of the ultratrace isotope Ca-41. (C) 2000 Optical Society of America. OCIS codes: 300.6210, 300.6320, 300.6350, 300.6300, 300.6410. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. Johannes Gutenberg Univ Mainz, Inst Phys, D-55099 Mainz, Germany. RP Nortershauser, W (reprint author), Pacific NW Natl Lab, 902 Battelle Blvd, Richland, WA 99352 USA. EM bruce.bushaw@pnl.gov RI Mueller, Peter/E-4408-2011; Wendt, Klaus/D-7306-2011; Nortershauser, Wilfried/A-6671-2013 OI Mueller, Peter/0000-0002-8544-8191; Wendt, Klaus/0000-0002-9033-9336; Nortershauser, Wilfried/0000-0001-7432-3687 NR 36 TC 24 Z9 24 U1 0 U2 0 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1559-128X EI 2155-3165 J9 APPL OPTICS JI Appl. Optics PD OCT 20 PY 2000 VL 39 IS 30 BP 5590 EP 5600 DI 10.1364/AO.39.005590 PG 11 WC Optics SC Optics GA 364ZV UT WOS:000089924700021 PM 18354556 ER PT J AU Sako, M Kahn, SM Paerels, F Liedahl, DA AF Sako, M Kahn, SM Paerels, F Liedahl, DA TI The physical conditions of the X-ray emission line regions in the Circinus galaxy SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies : active; galaxies : individual (Circinus); galaxies : Seyfert; galaxies : starburst; X-rays : galaxies ID ACTIVE GALACTIC NUCLEI; SEYFERT-2 GALAXIES; IRAS GALAXIES; COLD MATTER; PROFILES; NGC-1068; SPECTROSCOPY; ABUNDANCES; SPECTRUM; MODELS AB We present a detailed X-ray spectral analysis of the Circinus galaxy using archival data obtained with the ASCA satellite. The spectrum shows numerous emission lines in the soft X-ray band from highly ionized ions, as well as Compton reflection and fluorescent lines from neutral or near-neutral matter. We analyze the spectrum in the context of a self-consistent recombination cascade model and find that a nearly flat differential emission measure (DEM) distribution in ionization parameter fits the data. For a fixed solid angle distribution of matter surrounding a point source, this corresponds to a run of electron density of the form n(r) similar to r(-3/2), which is suggestive of Bondi accretion onto a central compact mass. Using this density profile and comparing the resulting emission spectra with the ASCA data, the size of the X-ray emission line region is estimated to be less than or similar to1 kpc. We also show that the derived density as a function of radius is compatible with the X-ray recombination line emission region being the confining medium of the coronal line regions. C1 Columbia Univ, Columbia Astrophys Lab, New York, NY 10027 USA. Columbia Univ, Dept Phys, New York, NY 10027 USA. SRON, Space Res Lab, NL-3584 CA Utrecht, Netherlands. Univ Calif Lawrence Livermore Natl Lab, Dept Phys & Space Sci, Livermore, CA 94550 USA. RP Sako, M (reprint author), Columbia Univ, Columbia Astrophys Lab, 538 W 120th St, New York, NY 10027 USA. NR 36 TC 10 Z9 10 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD OCT 20 PY 2000 VL 542 IS 2 BP 684 EP 691 DI 10.1086/317053 PN 1 PG 8 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 369YN UT WOS:000165095500015 ER PT J AU Alves, DR Nelson, CA AF Alves, DR Nelson, CA TI The rotation curve of the large magellanic cloud and the implications for microlensing SO ASTROPHYSICAL JOURNAL LA English DT Article DE dark matter; galaxies : structure; Galaxy : structure; Magellanic Clouds; stars : carbon; stars : kinematics ID INTERVENING STELLAR POPULATION; ON SPIRAL GALAXIES; SURFACE PHOTOMETRY; DARK MATTER; CH STARS; 3-DIMENSIONAL DISTRIBUTION; VELOCITY DISPERSION; GLOBULAR-CLUSTERS; OPTICAL DEPTH; PROPER MOTION AB The rotation of the disk of the Large Magellanic Cloud (LMC) is derived from the published radial velocities of 422 carbon stars. New aspects of this analysis include the propagation of uncertainties in the LMC proper motion with a Monte Carlo and a self-consistent modeling of the rotation curve and disk kinematics. The LMC rotation curve reaches a maximum circular velocity of 72 +/- 7 km s(-1) at R = 4.0 kpc and then declines. The rotation curve is well fitted by a truncated, finite-thickness exponential disk model with no dark halo, implying a total mass of 5.3 +/- 1.0 x 10(9) M.. The velocity dispersion in concentric radial bins from R = 0.5 to 5.6 kpc decreases from 22 to 15 km s(-1) and then increases to similar to 20 km s(-1) at larger radii. Constant-thickness disk models in virial equilibrium cannot be reconciled with the data even if the effects of LMC or Galactic dark halos are included. If the disk is virialized, the scale height rises from h = 0.3 to 1.6 kpc over the range of R = 0.5-5.6 kpc. Thus, the LMC disk is flared. We model the velocity dispersion at large radii (R > 6 kpc) as a maximal flared disk under the influence of the Galactic dark halo, which favors a mean density for the latter of <()over bar> similar to 2.5 x 10(-4) M. pc(-3) at the LMC distance. LMC stellar kinematics plays an important role in elucidating the nature of MACHOs, a dark population inferred from LMC microlensing. We have constructed a truncated and flared maximal disk model for the LMC that is kinematically based. Our model does not include a nonvirialized component such as tidal debris. The instantaneous probability of microlensing from LMC stars in our model is tau < 1.0 x 10(-8) sec(2) i, where i is the disk inclination. Our upper limit on the self-lensing optical depth is in good agreement with that obtained from less sophisticated models and is an order of magnitude too small to account for the MACHO microlensing signal. C1 Space Telescope Sci Inst, Baltimore, MD 21218 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Lawrence Livermore Natl Lab, Inst Geophys & Planetary Phys, Livermore, CA 94550 USA. RP Alves, DR (reprint author), Space Telescope Sci Inst, 3700 San Martin Dr, Baltimore, MD 21218 USA. NR 68 TC 73 Z9 74 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD OCT 20 PY 2000 VL 542 IS 2 BP 789 EP 803 DI 10.1086/317023 PN 1 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 369YN UT WOS:000165095500025 ER PT J AU Park, NG Chang, SH van de Lagemaat, J Kim, KJ Frank, AJ AF Park, NG Chang, SH van de Lagemaat, J Kim, KJ Frank, AJ TI Effect of cations on the open-circuit photovoltage and the charge-injection efficiency of dye-sensitized nanocrystalline rutile TiO2 films SO BULLETIN OF THE KOREAN CHEMICAL SOCIETY LA English DT Article ID NANOSTRUCTURED ZNO ELECTRODES; FLAT-BAND POTENTIALS; SOLAR-CELL; PHOTOELECTROCHEMICAL CHARACTERIZATION; SPECTROSCOPIC DETERMINATION; SYSTEMS; ENERGY; OXIDE AB Dye-sensitized nanocrystalline rutile TiO2 solar cells were prepared, and the influence of Li+ and 1,2dimethyl-3-hexyl imidazolium ions in the electrolyte on the photovoltaic properties was compared. The electrolyte containing Li+ ions produced a lower open-circuit photovoltage than the electrolyte with 1,2-dimethyl-3-hexyl imidazolium ions, suggesting that the adsorption of Li+ ions to the rutile TiO2 surface causes a shift in the band edges toward more positive potentials. At the same time, both the short-circuit photocurrent and the maximum value of the incident-photon-current conversion efficiency (IPCE) of the electrolyte containing Li+ ions were relatively higher. Data analysis suggests that presence of adsorbed Li+ ions improves via the phenomenon of band-edge movement the charge-injection efficiency by altering both the energy and number of excited state levels of the dye that participate in electron injection. C1 Elect & Telecommun Res Inst, Telecommun Basic Res Lab, Taejon 305350, South Korea. Natl Renewable Energy Lab, Golden, CO 80401 USA. Korea Univ, Dept Chem, Seoul 136701, South Korea. RP Park, NG (reprint author), Elect & Telecommun Res Inst, Telecommun Basic Res Lab, Taejon 305350, South Korea. RI van de Lagemaat, Jao/J-9431-2012; Park, Nam-Gyu/F-2477-2014 NR 19 TC 50 Z9 50 U1 0 U2 14 PU KOREAN CHEMICAL SOC PI SEOUL PA 635-4 YEOGSAM-DONG, KANGNAM-GU, SEOUL 135-703, SOUTH KOREA SN 0253-2964 J9 B KOR CHEM SOC JI Bull. Korean Chem. Soc. PD OCT 20 PY 2000 VL 21 IS 10 BP 985 EP 988 PG 4 WC Chemistry, Multidisciplinary SC Chemistry GA 391ZU UT WOS:000166386800009 ER PT J AU Brown, CM Yildirim, T Neumann, DA Heben, MJ Gennett, T Dillon, AC Alleman, JL Fischer, JE AF Brown, CM Yildirim, T Neumann, DA Heben, MJ Gennett, T Dillon, AC Alleman, JL Fischer, JE TI Quantum rotation of hydrogen in single-wall carbon nanotubes SO CHEMICAL PHYSICS LETTERS LA English DT Article ID GRAPHITE NANOFIBERS; LASER VAPORIZATION; SOLID C-60; ADSORPTION; STORAGE; H-2; ENERGY AB We report inelastic neutron scattering results on hydrogen adsorbed onto samples containing single-wall carbon nanotubes. These materials have attracted considerable interest recently due to reports of high density hydrogen storage at room temperature. Inelastic neutron scattering clearly shows the ortho-para conversion of physisorbed hydrogen in a nanotube containing soot loaded with hydrogen. From the rotational J = 0 --> 1 transition, no indication of a significant barrier to quantum rotation is seen. (C) 2000 Elsevier Science B.V. All rights reserved. C1 NIST, Ctr Neutron Res, Gaithersburg, MD 20899 USA. Univ Maryland, Dept Mat & Nucl Engn, College Pk, MD USA. Natl Renewable Energy Lab, Ctr Basic Sci, Golden, CO 80401 USA. Univ Penn, Dept Mat Sci & Engn, Philadelphia, PA 19104 USA. Rochester Inst Technol, Ctr Mat Sci & Engn, Rochester, NY 14623 USA. RP Neumann, DA (reprint author), NIST, Ctr Neutron Res, Gaithersburg, MD 20899 USA. RI yildirim, taner/A-1290-2009; Brown, Craig/B-5430-2009 OI Brown, Craig/0000-0002-9637-9355 NR 27 TC 118 Z9 120 U1 1 U2 10 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 OCT 20 PY 2000 VL 329 IS 3-4 BP 311 EP 316 DI 10.1016/S0009-2614(00)01003-4 PG 6 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 367WX UT WOS:000090085500019 ER PT J AU Kheyfets, A Miller, WA AF Kheyfets, A Miller, WA TI Time in quantum geometrodynamics SO INTERNATIONAL JOURNAL OF MODERN PHYSICS A LA English DT Article AB We revisit the issue of time in quantum geometrodynamics and suggest a quantization procedure on the space of true dynamic variables. This procedure separates the issue of quantization from enforcing the constraints caused by the general covariance symmetries. The resulting theory, unlike the standard approach, takes into account the states that are off shell with respect to the constraints, and thus avoids the problems of time. In this approach, quantum geometrodynamics, general covariance, and the interpretation of time emerge together as parts of the solution of the total problem of geometrodynamic evolution. C1 N Carolina State Univ, Dept Math, Raleigh, NC 27695 USA. Univ Calif Los Alamos Natl Lab, Div Theoret, Theoret Astrophys Grp, Los Alamos, NM 87545 USA. RP Kheyfets, A (reprint author), N Carolina State Univ, Dept Math, Box 8205, Raleigh, NC 27695 USA. NR 9 TC 3 Z9 3 U1 0 U2 0 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA JOURNAL DEPT PO BOX 128 FARRER ROAD, SINGAPORE 912805, SINGAPORE SN 0217-751X J9 INT J MOD PHYS A JI Int. J. Mod. Phys. A PD OCT 20 PY 2000 VL 15 IS 26 BP 4125 EP 4140 PG 16 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 372AF UT WOS:000165210900005 ER PT J AU Coburn, CT Knapp, FF Febbraio, M Beets, AL Silverstein, RL Abumrad, NA AF Coburn, CT Knapp, FF Febbraio, M Beets, AL Silverstein, RL Abumrad, NA TI Defective uptake and utilization of long chain fatty acids in muscle and adipose tissues of CD36 knockout mice SO JOURNAL OF BIOLOGICAL CHEMISTRY LA English DT Article ID DIACYLGLYCEROL ACYLTRANSFERASE; TRIACYLGLYCEROL SYNTHESIS; MEMBRANE-PROTEIN; CARDIAC MYOCYTES; BINDING PROTEIN; RAT HEPATOCYTES; UP-REGULATION; METABOLISM; TRANSPORT; ADIPOCYTES AB The transmembrane protein CD36 has been identified in isolated cell studies as a putative transporter of long chain fatty acids. In humans, an association between CD36 deficiency and defective myocardial uptake of the fatty acid analog 15-(p-iodophenyl)-3-(R,S)-methyl pentadecanoic acid (BMIPP) has been reported. To determine whether this association represents a causal link and to assess the physiological role of CD36, we compared tissue uptake and metabolism of two iodinated fatty acid analogs BMIPP and 15-(p-iodophenyl) pentadecanoic acid (IPPA) in CD36 null and wild type mice. We also investigated the uptake and lipid incorporation of palmitate by adipocytes isolated from both groups. Compared with wild type, uptake of BMIPP and IPPA was reduced in heart (50-80%), skeletal muscle (40-75%), and adipose tissues (60-70%) of nub mice. The reduction was associated with a 50-68% decrease in label incorporation into triglycerides and in 2-3-fold accumulation of label in diglycerides, Identical results were obtained from studies of [H-3]palmitate uptake in isolated adipocytes, The block in diglyceride to triglyceride conversion could not be explained by changes in specific activities of the key enzymes long chain acyl-CoA synthetase and diacylglycerol acyltransferase, which were similar in tissues from wild type and null mice. It is concluded that CD36 facilitates a large fraction of fatty acid uptake by heart, skeletal muscle, and adipose tissues and that CD36 deficiency in humans is the cause of the reported defect in myocardial BMIPP uptake. In CD36-expressing tissues, uptake regulates fatty acid esterification at the level of diacylglycerol acyltransferase by determining fatty acyl-CoA supply. The membrane transport step may represent an important control site for fatty acid metabolism in vivo. C1 SUNY Stony Brook, Dept Physiol & Biophys, Stony Brook, NY 11794 USA. Oak Ridge Natl Lab, Nucl Med Program, Oak Ridge, TN 37831 USA. Cornell Univ, Weill Med Coll, Div Hematol & Med Oncol, Dept Med, New York, NY 10021 USA. RP Abumrad, NA (reprint author), SUNY Stony Brook, Dept Physiol & Biophys, Stony Brook, NY 11794 USA. FU NHLBI NIH HHS [1R29 HL58559, HL42540]; NIDDK NIH HHS [DK33301] NR 49 TC 364 Z9 374 U1 1 U2 14 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 OCT 20 PY 2000 VL 275 IS 42 BP 32523 EP 32529 DI 10.1074/jbc.M003826200 PG 7 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 366KD UT WOS:000090003800021 PM 10913136 ER PT J AU Hoover, DM Rajashankar, KR Blumenthal, R Puri, A Oppenheim, JJ Chertov, O Lubkowski, J AF Hoover, DM Rajashankar, KR Blumenthal, R Puri, A Oppenheim, JJ Chertov, O Lubkowski, J TI The structure of human beta-defensin-2 shows evidence of higher order oligomerization SO JOURNAL OF BIOLOGICAL CHEMISTRY LA English DT Article ID MEMBRANE PERMEABILIZATION; ANTIMICROBIAL PEPTIDES; DIFFRACTION DATA; HUMAN DEFENSINS; LIPID BILAYERS; OUTER-MEMBRANE; BETA-DEFENSINS; PROTEIN; CRYSTALLOGRAPHY; REFINEMENT AB Defensins are small cationic peptides that are crucial components of innate immunity, serving as both antimicrobial agents and chemoattractant molecules. The specific mechanism of antimicrobial activity involves permeabilization of bacterial membranes. It has been postulated that individual monomers oligomerize to form a pore through anionic membranes, although the evidence is only indirect. Here, we report two high resolution x-ray structures of human beta -defensin-2 (hBD2). The phases were experimentally determined by the multiwavelength anomalous diffraction method, utilizing a novel, rapid method of derivatization with halide ions. Although the shape and charge distribution of the monomer are similar to those of other defensins, an additional alpha -helical region makes this protein topologically distinct from the mammalian alpha- and beta -defensin structures reported previously. hBD2 forms dimers topologically distinct from that of human neutrophil peptide-3. The quaternary octameric arrangement of hBD2 is conserved in two crystal forms. These structures provide the first detailed description of dimerization of beta -defensins, and we postulate that the mode of dimerization of hBD2 is representative of other beta -defensins. The structural and electrostatic properties of the hBD2 octamer support an electrostatic charge-based mechanism of membrane permeabilization by beta -defensins, rather than a mechanism based on formation of bilayer-spanning pores. C1 NCI, Macromol Crystallog Lab, Program Struct Biol, Frederick Canc Res & Dev Ctr,NIH, Frederick, MD 21702 USA. NCI, SAIC Frederick, Frederick Canc Res & Dev Ctr, NIH, Frederick, MD 21702 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. NCI, Lab Expt & Computat Biol, Frederick Canc Res & Dev Ctr, NIH, Frederick, MD 21702 USA. NCI, Mol Immunoregulat Lab, Frederick Canc Res & Dev Ctr, NIH, Frederick, MD 21702 USA. NCI, Intramural Res Support Program, SAIC Frederick, Frederick Canc Res & Dev Ctr,NIH, Frederick, MD 21702 USA. RP Lubkowski, J (reprint author), NCI, Macromol Crystallog Lab, Program Struct Biol, Frederick Canc Res & Dev Ctr,NIH, Frederick, MD 21702 USA. FU NCI NIH HHS [N01-CO-56000] NR 40 TC 206 Z9 224 U1 2 U2 9 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 OCT 20 PY 2000 VL 275 IS 42 BP 32911 EP 32918 DI 10.1074/jbc.M006098200 PG 8 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 366KD UT WOS:000090003800074 PM 10906336 ER PT J AU Kwiat, PG Berglund, AJ Altepeter, JB White, AG AF Kwiat, PG Berglund, AJ Altepeter, JB White, AG TI Experimental verification of decoherence-free subspaces SO SCIENCE LA English DT Article ID QUANTUM COMPUTATION; ENTANGLED STATES; DISSIPATION; COMPUTERS; SEARCH; CODES AB Using spontaneous parametric down-conversion, we produce polarization-entangled states of two photons and characterize them using two-photon tomography to measure the density matrix. A controllable decoherence is imposed on the states by passing the photons through thick, adjustable birefringent elements. When the system is subject to collective decoherence, one particular entangled state is seen to be decoherence-free, as predicted by theory. Such decoherence-free systems may have an important role for the future of quantum computation and information processing. C1 Los Alamos Natl Lab, Div Phys, Los Alamos, NM 87545 USA. Univ Queensland, Dept Phys, Brisbane, Qld 4072, Australia. RP Kwiat, PG (reprint author), Los Alamos Natl Lab, Div Phys, P-23, Los Alamos, NM 87545 USA. RI Altepeter, Joseph/F-7878-2010; White, Andrew/A-1088-2009 OI White, Andrew/0000-0001-9639-5200 NR 23 TC 302 Z9 303 U1 1 U2 21 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 OCT 20 PY 2000 VL 290 IS 5491 BP 498 EP 501 DI 10.1126/science.290.5491.498 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 365HN UT WOS:000089946000045 PM 11039926 ER PT J AU Hein, M Dumas, P Otto, A Williams, GP AF Hein, M Dumas, P Otto, A Williams, GP TI CO interaction with co-adsorbed C2H4 on Cu(111) as revealed by friction with the conduction electrons SO SURFACE SCIENCE LA English DT Article DE adsorption kinetics; alkenes; carbon monoxide; copper; friction; infrared absorption spectroscopy; metallic films; reflection spectroscopy; surface electrical transport (surface conductivity; surface recombination, etc.) ID SURFACE RESISTIVITY; RESISTANCE; ADSORPTION; VIBRATIONS; STATES; LAYERS; FILMS AB Simultaneous measurements of the DC resistance and IR reflectivity changes of thin epitaxially grown copper (111) films have been performed during co-adsorption of CO with C2H4. The linear dependence of these two quantities, which has previously been observed for CO on Cu(lll) films, also holds for this coadsorbed system. Importantly, we have shown that the linearity factor is independent of the adsorbate type, as predicted by the scattering model of the conduction electrons. Co-adsorption of CO with C2H4 results in markedly more pronounced changes in IR reflectance and in resistance; these changes are higher than the sum of the individual changes of each species. The results are interpreted as a consequence of covalent through-metal bonding of the adsorbates via the lowest unoccupied molecular orbitals, (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Dusseldorf, IPkM, Lehrstuhl Oberflachenwissensch, D-40225 Dusseldorf, Germany. Ctr Univ Paris Sud, LURE, F-91405 Orsay, France. Ctr Univ Paris Sud, CNRS, LASIR, F-91405 Orsay, France. Brookhaven Natl Lab, Natl Synchrotron Light Source, Upton, NY 11973 USA. RP Otto, A (reprint author), Univ Dusseldorf, IPkM, Lehrstuhl Oberflachenwissensch, D-40225 Dusseldorf, Germany. NR 19 TC 26 Z9 26 U1 2 U2 9 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 J9 SURF SCI JI Surf. Sci. PD OCT 20 PY 2000 VL 465 IS 3 BP 249 EP 258 DI 10.1016/S0039-6028(00)00681-6 PG 10 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA 370CZ UT WOS:000165106500011 ER PT J AU Kellogg, GL Plass, R AF Kellogg, GL Plass, R TI The relationship between the growth shape of three-dimensional Pb islands on Cu(100) and the domain orientation of the underlying c(5 root 2 x root 2)R45 structure SO SURFACE SCIENCE LA English DT Letter DE copper; epitaxy; lead; low energy electron diffraction (LEED); low-energy electron microscopy (LEEM); low index single crystal surfaces; surface structure; morphology; roughness; and topography ID SURFACE ALLOY; LOW-INDEX; SCATTERING; LEAD; COPPER; ADSORPTION; OVERLAYERS; HELIUM; PHASE; LEED AB We use low-energy electron microscopy to identify a correlation between the growth shape of three-dimensional Pb islands on Cu(100) and the domain structure of the underlying Pb overlayer. Deposition of 0.6 monolayer Pb on Cu(100) produces a compressed c(2 x 2) overlayer, designated c(5 root2 x root2)R45, with periodic rows of anti-phase boundaries. We find that heating the surface to temperatures above 100 degreesC coarsens the orientational domains of this structure to sizes that are easily resolved in the low-energy electron microscope. Three-dimensional Pb islands, grown on the coarsened domains, are found to be asymmetric with orientations that correlate with the domain structure. Once nucleated with a preferred growth orientation, islands continue to grow with the same preferred orientation, even across domain boundaries. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Kellogg, GL (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. EM glkello@sandia.gov NR 15 TC 8 Z9 8 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 J9 SURF SCI JI Surf. Sci. PD OCT 20 PY 2000 VL 465 IS 3 BP L777 EP L782 DI 10.1016/S0039-6028(00)00784-6 PG 6 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA 370CZ UT WOS:000165106500002 ER PT J AU Lightstone, JM Onasch, TB Imre, D Oatis, S AF Lightstone, JM Onasch, TB Imre, D Oatis, S TI Deliquescence, efflorescence, and water activity in ammonium nitrate and mixed ammonium nitrate/succinic acid microparticles SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID SECONDARY ORGANIC AEROSOL; AIRBORNE PARTICULATE MATTER; DICARBOXYLIC-ACIDS; HETEROGENEOUS NUCLEATION; HYGROSCOPIC PROPERTIES; ATMOSPHERIC PARTICLES; RELATIVE-HUMIDITY; AQUEOUS-SOLUTIONS; URBAN ATMOSPHERE; POLAR COMPOUNDS AB We have investigated the thermodynamics and kinetics of ammonium nitrate/water and mixed ammonium nitrate/succinic acid/water microparticles. The water activity of ammonium nitrate microparticles is determined as a function of composition down to 12% relative humidity by accounting for the rapid evaporation of ammonia and nitric acid. Both the observed deliquescence and water activities for ammonium nitrate/water microparticles are found to be in good agreement with predicted values. Supermicron ammonium nitrate particles generated from high-purity methanol are found not to effloresce, but form an anhydrous liquid state observed only in particle form. We also present data on the hydroscopicity and phase transitions of internally mixed ammonium nitrate/succinic acid particles. A pronounced reduction in the particle growth factor at deliquescence is reported, indicating that the succinic acid does not take up a significant amount of water. Additionally, the deliquescence relative humidity is found to decrease slightly as the mass percent of succinic acid is increased from 12.5 to 50%. Solid succinic acid in ammonium nitrate drops acts to catalyze efflorescence of ammonium nitrate at high relative humidity. However, when the relative humidity is increased sufficiently to completely dissolve the succinic acid, no efflorescence is observed. The resulting data are analyzed using classical nucleation theory to derive the free energy barrier to nucleation, the critical supersaturation, the size of the critical nucleus, and the contact parameter between ammonium nitrate crystal and the solid succinic acid. C1 Brookhaven Natl Lab, Dept Environm Sci, Div Atmospher Sci, Upton, NY 11973 USA. Long Isl Univ, Southampton Coll, Div Nat Sci, Southampton, NY 11968 USA. RP Brookhaven Natl Lab, Dept Environm Sci, Div Atmospher Sci, Upton, NY 11973 USA. NR 60 TC 130 Z9 132 U1 7 U2 26 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 OCT 19 PY 2000 VL 104 IS 41 BP 9337 EP 9346 DI 10.1021/jp002137h PG 10 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 372LW UT WOS:000165236000009 ER PT J AU Horne, CR Bergmann, U Grush, MM Perera, RCC Ederer, DL Callcott, TA Cairns, EJ Cramer, SP AF Horne, CR Bergmann, U Grush, MM Perera, RCC Ederer, DL Callcott, TA Cairns, EJ Cramer, SP TI Electronic structure of chemically-prepared LixMn2O4 determined by Mn X-ray absorption and emission spectroscopies SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID FINE-STRUCTURE SPECTROSCOPY; LITHIUM MANGANESE OXIDES; SPINEL-TYPE OXIDES; LOCAL-STRUCTURE; FTIR SPECTROSCOPY; OXIDATION-STATE; K-EDGE; METAL; TRANSITION; XANES AB We have performed Mn K-edge X-ray Absorption and Mn L-edge emission spectroscopies on LiMn2O4, its chemically delithiated and lithiated derivatives (lambda -MnO2 and Li2Mn2O4, respectively), and two Mn3+ spinel model compounds. These experiments were undertaken to understand the associated changes in atomic and electronic structure occurring when LiMn2O4 is used in a rechargeable lithium cell. Subtle changes In the Mn K-edge X-ray absorption near edge structure (XANES) occur upon delithiation that are consistent with literature reports of the oxidation of Mn3+ to Mn4+, retention of the cubic phase, and contraction of the spinel lattice. Conversely, when LiMn2O4 is lithiated, the XANES changes dramatically due to the concurrent transformation from a cubic to a tetragonal spinel. The spectrum is different from XANES of tetragonal Mn3+ spinels possessing approximately the same degree of tetragonal distortion as Li2Mn2O4. This spectral difference is attributed to the inserted Li+ imparting an increased degree of covalency within the Li2Mn2O4 structure resulting in a Is --> 4p + LMCT (ligand to metal charge transfer) shakedown. This increase in covalency was confirmed through Mn L-edge X-ray Emission Spectroscopy measurements. The increased degree of covalency provides insight into the lower Li+ diffusion coefficients reported in the literature and the electronic conduction mechanism for LixMn2O4 when x > 1. C1 Ernest Orlando Lawrence Berkeley Natl Lab, Environm Energy Technol Div, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Mat Sci & Mineral Engn, Berkeley, CA 94720 USA. Ernest Orlando Lawrence Berkeley Natl Lab, Struct Biol Div, Berkeley, CA 94720 USA. Ernest Orlando Lawrence Berkeley Natl Lab, Ctr Xray Opt, Berkeley, CA 94720 USA. Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. Tulane Univ, New Orleans, LA 70118 USA. Univ Calif Berkeley, Dept Chem Engn, Berkeley, CA 94720 USA. Univ Calif Davis, Dept Appl Sci, Davis, CA 95616 USA. RP NanoGram Corp, Fremont, CA 94538 USA. RI Cairns, Elton/E-8873-2012 OI Cairns, Elton/0000-0002-1179-7591 NR 67 TC 34 Z9 34 U1 2 U2 34 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1520-6106 J9 J PHYS CHEM B JI J. Phys. Chem. B PD OCT 19 PY 2000 VL 104 IS 41 BP 9587 EP 9596 DI 10.1021/jp994475s PG 10 WC Chemistry, Physical SC Chemistry GA 372KP UT WOS:000165233100004 ER PT J AU Link, JM Paolone, VS Reyes, M Yager, PM Anjos, JC Bediaga, I Gobel, C Magnin, J de Miranda, JM Pepe, IM dos Reis, AC Simao, FRA Carrillo, S Casimiro, E Mendez, H Sanchez-Hernandez, A Uribe, C Vazquez, F Cinquini, L Cumalat, JP Ramirez, JE O'Reilly, B Vaandering, EW Butler, JN Cheung, HWK Gaines, I Garbincius, PH Garren, LA Gottschalk, E Gourlay, SA Kasper, PH Kreymer, AE Kutschke, R Bianco, S Fabbri, FL Sarwar, S Zallo, A Cawlfield, C Kim, DY Park, KS Rahimi, A Wiss, J Gardner, R Chung, YS Kang, JS Ko, BR Kwak, JW Lee, KB Myung, SS Park, H Alimonti, G Boschini, M Brambilla, D Caccianiga, B Calandrino, A D'Angelo, P DiCorato, M Dini, P Giammarchi, M Inzani, P Leveraro, F Malvezzi, S Menasce, D Mezzadri, M Milazzo, L Moroni, L Pedrini, D Prelz, F Rovere, M Sala, A Sala, S Davenport, TF Arena, V Boca, G Bonomi, G Gianini, G Liguori, G Merlo, M Pantea, D Ratti, SP Riccardi, C Torre, P Viola, L Vitulo, P Hernandez, H Lopez, AM Mendez, L Mirles, A Montiel, E Olaya, D Quinones, J Rivera, C Zhang, Y Copty, N Purohit, M Wilson, JR Cho, K Handler, T Engh, D Johns, WE Hosack, M Nehring, MS Sales, M Sheldon, PD Stenson, K Webster, MS Sheaff, M Kwon, Y AF Link, JM Paolone, VS Reyes, M Yager, PM Anjos, JC Bediaga, I Gobel, C Magnin, J de Miranda, JM Pepe, IM dos Reis, AC Simao, FRA Carrillo, S Casimiro, E Mendez, H Sanchez-Hernandez, A Uribe, C Vazquez, F Cinquini, L Cumalat, JP Ramirez, JE O'Reilly, B Vaandering, EW Butler, JN Cheung, HWK Gaines, I Garbincius, PH Garren, LA Gottschalk, E Gourlay, SA Kasper, PH Kreymer, AE Kutschke, R Bianco, S Fabbri, FL Sarwar, S Zallo, A Cawlfield, C Kim, DY Park, KS Rahimi, A Wiss, J Gardner, R Chung, YS Kang, JS Ko, BR Kwak, JW Lee, KB Myung, SS Park, H Alimonti, G Boschini, M Brambilla, D Caccianiga, B Calandrino, A D'Angelo, P DiCorato, M Dini, P Giammarchi, M Inzani, P Leveraro, F Malvezzi, S Menasce, D Mezzadri, M Milazzo, L Moroni, L Pedrini, D Prelz, F Rovere, M Sala, A Sala, S Davenport, TF Arena, V Boca, G Bonomi, G Gianini, G Liguori, G Merlo, M Pantea, D Ratti, SP Riccardi, C Torre, P Viola, L Vitulo, P Hernandez, H Lopez, AM Mendez, L Mirles, A Montiel, E Olaya, D Quinones, J Rivera, C Zhang, Y Copty, N Purohit, M Wilson, JR Cho, K Handler, T Engh, D Johns, WE Hosack, M Nehring, MS Sales, M Sheldon, PD Stenson, K Webster, MS Sheaff, M Kwon, Y CA FOCUS Collaboration TI Search for violation in D-0 and D+ decays SO PHYSICS LETTERS B LA English DT Article ID CP VIOLATION; MESON DECAYS AB A high statistics sample of photoproduced charm particles from the FOCUS (E831) experiment at Fermilab has been used to search for CP violation in the Cabibbo suppressed decay modes D+ --> K(-)K(+)pi (+), D-0 --> K-K+ and D-0 --> pi (-)pi (+) We have measured the following CP asymmetry parameters: A(CP)(K(-)K(+)pi (+)) = +0.006 +/- 0.011 +/- 0.005, A(CP)(K-Kf) = -0.001 +/- 0.022 +/- 0.015 and A(CP)(pi (-)pi (+)) = +0.048 +/- 0.039 +/- 0.025 where the first error is statistical and the second error is systematic. These asymmetries are consistent with zero with smaller errors than previous measurements. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Ist Nazl Fis Nucl, I-20133 Milan, Italy. Univ Milan, Milan, Italy. Univ Calif Davis, Davis, CA 95616 USA. Ctr Brasileiro Pesquisas Fis, Rio De Janeiro, RJ, Brazil. CINVESTAV, Mexico City 07000, DF, Mexico. Univ Colorado, Boulder, CO 80309 USA. Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. Ist Nazl Fis Nucl, Nazl Frascati Lab, I-00044 Frascati, Italy. Univ Illinois, Urbana, IL 61801 USA. Indiana Univ, Bloomington, IN 47405 USA. Korea Univ, Seoul 136701, South Korea. Univ N Carolina, Asheville, NC 28804 USA. Dipartimento Fis Nucl & Teor, Pavia, Italy. Ist Nazl Fis Nucl, I-27100 Pavia, Italy. Univ Puerto Rico, Mayaguez, PR 00681 USA. Univ S Carolina, Columbia, SC 29208 USA. Univ Tennessee, Knoxville, TN 37996 USA. Vanderbilt Univ, Nashville, TN 37235 USA. Univ Wisconsin, Madison, WI 53706 USA. Yonsei Univ, Seoul 120749, South Korea. RP Pedrini, D (reprint author), Ist Nazl Fis Nucl, Via Celoria 16, I-20133 Milan, Italy. RI Bonomi, Germano/G-4236-2010; Kwak, Jungwon/K-8338-2012; Anjos, Joao/C-8335-2013; Link, Jonathan/L-2560-2013; Gobel Burlamaqui de Mello, Carla /H-4721-2016; Menasce, Dario Livio/A-2168-2016; Gianini, Gabriele/M-5195-2014 OI Kutschke, Robert/0000-0001-9315-2879; bianco, stefano/0000-0002-8300-4124; Bonomi, Germano/0000-0003-1618-9648; Link, Jonathan/0000-0002-1514-0650; Gobel Burlamaqui de Mello, Carla /0000-0003-0523-495X; Menasce, Dario Livio/0000-0002-9918-1686; Gianini, Gabriele/0000-0001-5186-0199 NR 14 TC 28 Z9 28 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 J9 PHYS LETT B JI Phys. Lett. B PD OCT 19 PY 2000 VL 491 IS 3-4 BP 232 EP 239 DI 10.1016/S0370-2693(00)01039-X PG 8 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 369GM UT WOS:000165057600003 ER PT J AU Littenberg, LS Shrock, R AF Littenberg, LS Shrock, R TI Implication of improved upper bounds on vertical bar Delta L vertical bar=2 processes SO PHYSICS LETTERS B LA English DT Article ID DOUBLE-BETA DECAY; MAJORANA-NEUTRINO; MESON DECAYS; CONVERSION; SEARCH AB We discuss implications of improved upper bounds on the \DeltaL\ = 2 processes (i) K+ --> pi (-)mu (+)mu (+), from an experiment at BNL, and (ii) mu (-) --> e(+) conversion, from an experiment at PSI. In particular, we address the issue of constraints on neutrino masses and mixing, and on supersymmetric models with R-parity violation. (C) 2000 Published by Elsevier Science B.V. C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Littenberg, LS (reprint author), Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. OI Littenberg, Laurence/0000-0001-8373-7179 NR 27 TC 39 Z9 39 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 OCT 19 PY 2000 VL 491 IS 3-4 BP 285 EP 290 DI 10.1016/S0370-2693(00)01041-8 PG 6 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 369GM UT WOS:000165057600011 ER PT J AU Hay, BP Nicholas, JB Feller, D AF Hay, BP Nicholas, JB Feller, D TI Novel binding modes in tetramethoxycalix[4]arene: Implications for ligand design SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID CATION-PI INTERACTIONS; KINETICALLY STABLE COMPLEXES; ALKALI-METAL CATIONS; RARE-GAS DIATOMICS; DER-WAALS FORCES; MOLECULAR MECHANICS; BASIS-SETS; RIGIDIFIED CALIX<4>ARENES; DONOR PARTICIPATION; HIGH IONOPHORICITY AB Calixarenes are used as molecular scaffolds for the preparation of novel receptors for cations, anions, and neutral molecules. Although widely studied, the nature of the host-guest interactions within these molecules remains obscure. We present a combined density-functional theory and second-order perturbation theory study of the complexation of the alkali cations Na+ and Cs+ with tetramethoxycalix[4]arene. The results show that the host-guest interactions of this simple system are much more complex than previously thought and suggest new approaches for the design of selective cation receptors. C1 Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Hay, BP (reprint author), Pacific NW Natl Lab, Environm Mol Sci Lab, POB 999, Richland, WA 99352 USA. NR 83 TC 51 Z9 52 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 OCT 18 PY 2000 VL 122 IS 41 BP 10083 EP 10089 DI 10.1021/ja9937066 PG 7 WC Chemistry, Multidisciplinary SC Chemistry GA 368FT UT WOS:000090107600024 ER PT J AU Gutowski, M Skurski, P Simons, J AF Gutowski, M Skurski, P Simons, J TI Dipole-bound anions of glycine based on the zwitterion and neutral structures SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID SALT-BRIDGE STRUCTURES; GAS-PHASE; ELECTRONIC-STRUCTURE; ARGININE AB The instability of the zwitterion structure of glycine is significantly reduced by the attachment of an excess electron as a result of which a local minimum develops on the anionic potential energy surface for the zwitterion structure. However, the global anionic minimum, which is lower by 9 kcal/mol, corresponds to a singly hydrogen-bonded nonzwitterion structure. The vertical electron detachment energies for these two dipole-bound zwitterion and nonzwitterion structures are 3175 and 668 cm(-1), respectively. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. Univ Utah, Dept Chem, Henry Eyring Ctr Theoret Chem, Salt Lake City, UT 84112 USA. Univ Gdansk, Dept Chem, PL-80952 Gdansk, Poland. RP Gutowski, M (reprint author), Pacific NW Natl Lab, Richland, WA 99352 USA. NR 28 TC 118 Z9 118 U1 0 U2 4 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 OCT 18 PY 2000 VL 122 IS 41 BP 10159 EP 10162 DI 10.1021/ja001658f PG 4 WC Chemistry, Multidisciplinary SC Chemistry GA 368FT UT WOS:000090107600034 ER PT J AU Adler, M Davey, DD Phillips, GB Kim, SH Jancarik, J Rumennik, G Light, DR Whitlow, M AF Adler, M Davey, DD Phillips, GB Kim, SH Jancarik, J Rumennik, G Light, DR Whitlow, M TI Preparation, characterization, and the crystal structure of the inhibitor ZK-807834 (CI-1031) complexed with factor Xa SO BIOCHEMISTRY LA English DT Article ID BLOOD-COAGULATION; PROCOAGULANT ACTIVITY; THROMBIN; TRYPSIN; DESIGN; POTENT; MODEL AB Factor Xa plays a critical role in the formation of blood clots. This serine protease catalyzes the conversion of prothrombin to thrombin, the first joint step that links the intrinsic and extrinsic coagulation pathways. There is considerable interest in the development of factor Xa inhibitors for the intervention in thrombic diseases. This paper presents the structure of the inhibitor ZK-807834, also known as CI-1031, bound to factor Xa and provides the details of the protein purification and crystallization. Results from mass spectrometry indicate that the factor Xa underwent autolysis during crystallization and the first EGF-like domain was cleaved from the protein. The crystal structure of the complex shows that the amidine of ZK-807834 forms a salt bridge with Asp189 in the S1 pocket and the basic imidazoline fits snugly into the S4 site. The central pyridine ring provides a fairly rigid linker between these groups. This rigidity helps minimize entropic losses during binding. In addition, the structure reveals new interactions that were not found in the previous factor Xa/inhibitor complexes. ZK-807834 forms a strong hydrogen bond between an ionized 2-hydroxy group and Ser195 of factor Xa. There is also an aromatic ring-stacking interaction between the inhibitor and Trp215 in the S4 pocket. These interactions contribute to both the potency of this compound (K-I = 0.11 nM) and the >2500-fold selectivity against homologous serine proteases such as trypsin. C1 Berlex Biosci, Richmond, CA 94804 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. RP Whitlow, M (reprint author), Berlex Biosci, 15049 San Pablo Ave,POB 4099, Richmond, CA 94804 USA. NR 25 TC 94 Z9 94 U1 0 U2 5 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0006-2960 J9 BIOCHEMISTRY-US JI Biochemistry PD OCT 17 PY 2000 VL 39 IS 41 BP 12534 EP 12542 DI 10.1021/bi001477q PG 9 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 372BQ UT WOS:000165214100003 PM 11027132 ER PT J AU Liang, L Rieke, PC Liu, J Fryxell, GE Young, JS Engelhard, MH Alford, KL AF Liang, L Rieke, PC Liu, J Fryxell, GE Young, JS Engelhard, MH Alford, KL TI Surfaces with reversible hydrophilic/hydrophobic characteristics on cross-linked poly(N-isopropylacrylamide) hydrogels SO LANGMUIR LA English DT Article ID TEMPERATURE-SENSITIVE MEMBRANES; HYDROPHILIC-HYDROPHOBIC SURFACE; N-ISOPROPYLACRYLAMIDE; PHASE-TRANSITION; POLYMER; GELS; PHOTOPOLYMERIZATION; IMMOBILIZATION; CATALYSIS; PLATE AB Temperature-sensitive surfaces were prepared by grafting paly(N-isopropylacrylamide) (PNIPAAm) hydrogel on the surface of silicone wafers. The silicone wafer substrates were modified by organosilane (vinyltriethoxylsilane). They were further reacted with N-isopropylacrylamide (NIPAAm), using N,N'-methylenebisaerylamide as the cross-linking agent, to generate the cross-linked PNIPAAm layer on the surface of the substrate. The surfaces modified by the cross-linked PNIPAAm layer were characterized by scanning electron microscopy, X-ray photoelectron spectroscopy, and attenuated total reflectance-Fourier transform infrared (FTIR) spectroscopy. The reversible hydrophilic/hydrophobic properties of the surface were evaluated by the dynamic contact angle. The morphology of the surface modified by a crosslinked PNIPAAm layer can be turned fr-om "sea island" to "mountain valley" by changing the molar ratio of NIPAAm to BisAAm and by varying the polymerization time. A completely hydrophilic surface (advancing contact angle = 0 degrees) was observed below 25 degrees C, and the surface became extremely hydrophobic (advancing contact angle 92 degrees) above 40 degrees C. The sensitivity of the surfaces to temperature change can be improved by increasing the cross-linking density of the polymer layer and varying the polymerization time. The water meniscus height in a capillary tube, whose wall was coated by a cross-linked PNIPAAm layer, went up or down as the temperature changed to below or above the lower critical solution temperature of PNIPAAm. The differences in the water meniscus heights are 10 and 5 mm for a capillary tube with a diameter of 2 and 3 mm, respectively, corresponding to a change in temperature from 23 to 50 degrees C. The temperature-sensitive characteristics, which produce remarkable and rapid changes of surface properties, make this technology applicable for use as actuators, modulators, sensors, and switches. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. RP Liang, L (reprint author), Pacific NW Natl Lab, POB 999, Richland, WA 99352 USA. RI Engelhard, Mark/F-1317-2010; OI Engelhard, Mark/0000-0002-5543-0812 NR 31 TC 80 Z9 80 U1 4 U2 35 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0743-7463 J9 LANGMUIR JI Langmuir PD OCT 17 PY 2000 VL 16 IS 21 BP 8016 EP 8023 DI 10.1021/la0010929 PG 8 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 362VX UT WOS:000089799900022 ER PT J AU Magni, E Koranyi, TI Somorjai, GA AF Magni, E Koranyi, TI Somorjai, GA TI Gold-induced MgCl2 reduction by AlEt3. Surface science study of a novel reaction and its potential application in Ziegler-Natta catalysis SO LANGMUIR LA English DT Article ID CHLORIDE THIN-FILMS; MAGNESIUM-CHLORIDE; TITANIUM CHLORIDE; ELECTRONIC-STRUCTURE; XPS; DEPOSITION; MONOLAYER; PD(111); METAL; TICL4 AB A novel surface reaction for the reduction of MgCl2 by AlEt3 in the presence of Au is reported. MgCl2 submonolayer and multilayer films are prepared by gas-phase deposition over polycrystalline gold in UHV. When submonolayer MgCl2 films are exposed to liquid AlEt3, the halide is reduced, with the formation of Mg clusters or islands, covered with hydrocarbon fragments. The reduction of the halide at the Au surface is faster, and more complete, when MgCl2 and AlEt3 molecular beams are simultaneously directed at the metal surface. The reduced Mg surface reacts promptly with gas-phase TiCl4, and a TiCl2/TiCl4 film is thus deposited. This experiment demonstrates the feasibility of producing a MgCl2 support with a large fraction of its surface capable of TiCl4 chemisorption. Thd possibility of synthesizing Ziegler-Natta catalysts with a large density of active sites is discussed. C1 Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Dept Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Sci Mat, Berkeley, CA 94720 USA. RP Somorjai, GA (reprint author), Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Dept Chem, Berkeley, CA 94720 USA. RI Koranyi, Tamas/F-2422-2011 OI Koranyi, Tamas/0000-0003-4728-0081 NR 36 TC 7 Z9 7 U1 0 U2 7 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0743-7463 J9 LANGMUIR JI Langmuir PD OCT 17 PY 2000 VL 16 IS 21 BP 8113 EP 8121 DI 10.1021/la000443g PG 9 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 362VX UT WOS:000089799900034 ER PT J AU Schmidt, TJ Behm, RJ Grgur, BN Markovic, NM Ross, PN AF Schmidt, TJ Behm, RJ Grgur, BN Markovic, NM Ross, PN TI Formic acid oxidation on pure and Bi-modified Pt(111): Temperature effects SO LANGMUIR LA English DT Article ID DEFINED PLATINUM SURFACES; IRREVERSIBLY ADSORBED ADATOMS; POISON FORMATION REACTION; SINGLE-CRYSTAL SURFACES; UNDERPOTENTIAL DEPOSITION; HETEROGENEOUS ELECTROCATALYSIS; INFRARED-SPECTROSCOPY; ELECTRODES; BISMUTH; METHANOL AB Temperature effects on the kinetics of formic acid electrooxidation are studied on Pt(111) and on Pt(111) modified by irreversibly adsorbed Bi under both potentiodynamic and potentiostatic conditions. We propose two modes of action of irreversibly adsorbed Pi on the kinetics of HCOOH oxidation: (i) the inhibiting effect due to a blocking of active Pt sites and (ii) the catalytic effect due to the enhanced adsorption of OHad on the Pt sites adjacent to Bi. This counteracting behavior led to the fact that under steady-state conditions no difference in the overall activity was observed between Pt(111) and Pt(111)/Bi. Therefore, Pt(111)/Bi does not represent a catalytically active system of technological relevance. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Sci Mat, Berkeley, CA 94720 USA. Univ Ulm, Abt Oberflachenchem & Katalyse, D-89069 Ulm, Germany. RP Schmidt, TJ (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Sci Mat, Berkeley, CA 94720 USA. RI Schmidt, Thomas/A-2586-2010; OI Schmidt, Thomas/0000-0002-1636-367X; Grgur, Branimir/0000-0003-4684-9053 NR 34 TC 64 Z9 65 U1 2 U2 17 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0743-7463 J9 LANGMUIR JI Langmuir PD OCT 17 PY 2000 VL 16 IS 21 BP 8159 EP 8166 DI 10.1021/la000339z PG 8 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 362VX UT WOS:000089799900041 ER PT J AU Hayakawa, T Wang, JG Xiang, ML Li, XF Ueda, M Ober, CK Genzer, J Sivaniah, E Kramer, EJ Fischer, DA AF Hayakawa, T Wang, JG Xiang, ML Li, XF Ueda, M Ober, CK Genzer, J Sivaniah, E Kramer, EJ Fischer, DA TI Effect of changing molecular end groups on surface properties: Synthesis and characterization of poly(styrene-b-semifluorinated isoprene) block copolymers with -CF2H end groups SO MACROMOLECULES LA English DT Article ID DIBLOCK COPOLYMERS; SIDE-CHAINS; TENSIONS AB Poly(styrene-b-semifluorinated isoprene) block copolymers with -CF2H-terminated side groups were synthesized by the esterification reaction of a poly(styrene-b-hydroxylated 1,2-/3,4-isoprene) block copolymer with semifluorinated acid chlorides. Two distinct first-order transitions were observed by DSC measurements in the resulting block copolymers at temperatures below the glass transition of polystyrene. The transition temperatures of the longer fluorocarbon units (10 -CF2- units) were found to be higher than the shorter fluorocarbon units (eight -CF2- units). By comparing the block copolymers having -CF3 end groups with those with -CF2H end groups, it was found that both the thermal behavior and surface properties are significantly affected by the terminal group of the semifluorinated side chains in the block copolymer. NEXAFS spectroscopy reveals that, although the surface coverage by semifluorinated groups is roughly the same regardless of whether the ends are -CF2H or -CF3, the orientational order of the -CF2H surfaces is significantly poorer than that of the -CF3 surfaces. After long-term water exposure the -CF2H surfaces were observed to reconstruct to more hydrophilic ones even though the analogous polymers with -CF3-terminated semifluorinated side chains were quite stable. The ease of surface reconstruction is probably related to the relatively poor orientation order of the polymers with -CF2H end groups as determined by NEXAFS. C1 Cornell Univ, Ithaca, NY 14853 USA. Yamagata Univ, Grad Sch Engn, Yonezawa, Yamagata 992, Japan. NCSU, Dept Chem Engn, Raleigh, NC USA. Univ Calif Santa Barbara, Dept Mat, Santa Barbara, CA 93106 USA. Univ Calif Santa Barbara, Dept Chem Engn, Santa Barbara, CA 93106 USA. NIST, Mat Sci & Engn Lab, Gaithersburg, MD 20899 USA. Brookhaven Natl Lab, NSLS, Upton, NY 11973 USA. RP Hayakawa, T (reprint author), Cornell Univ, Ithaca, NY 14853 USA. NR 18 TC 48 Z9 49 U1 1 U2 6 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0024-9297 J9 MACROMOLECULES JI Macromolecules PD OCT 17 PY 2000 VL 33 IS 21 BP 8012 EP 8019 DI 10.1021/ma992112k PG 8 WC Polymer Science SC Polymer Science GA 367ZH UT WOS:000090092300049 ER PT J AU Wiederrecht, GP Yoon, BA Wasielewski, MR AF Wiederrecht, GP Yoon, BA Wasielewski, MR TI Photorefractivity in ferroelectric liquid crystal composites containing electron donor and acceptor molecules SO ADVANCED MATERIALS LA English DT Article ID POLYMER; GAIN; DIFFRACTION C1 Northwestern Univ, Dept Chem, Evanston, IL 60208 USA. Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. RP Wasielewski, MR (reprint author), Northwestern Univ, Dept Chem, Evanston, IL 60208 USA. NR 31 TC 56 Z9 56 U1 0 U2 2 PU WILEY-V C H VERLAG GMBH PI BERLIN PA PO BOX 10 11 61, D-69451 BERLIN, GERMANY SN 0935-9648 J9 ADV MATER JI Adv. Mater. PD OCT 16 PY 2000 VL 12 IS 20 BP 1533 EP 1536 DI 10.1002/1521-4095(200010)12:20<1533::AID-ADMA1533>3.0.CO;2-R PG 4 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 372QF UT WOS:000165244300017 ER PT J AU Mao, SS Mao, X Greif, R Russo, RE AF Mao, SS Mao, X Greif, R Russo, RE TI Initiation of an early-stage plasma during picosecond laser ablation of solids SO APPLIED PHYSICS LETTERS LA English DT Article ID ELECTRON-EMISSION; HEAT-TRANSFER; METALS; ALGORITHM; DYNAMICS; PULSES AB Picosecond time-resolved images of plasma initiation were recorded during pulsed-laser ablation of metal targets in an air atmosphere. An early-stage plasma was observed to form before the release of a material vapor plume. Close to the target surface, interferometry measurements indicate that the early-stage plasma has an electron number density on the order of 10(20) cm(-3). The longitudinal expansion of the ionization front for this plasma has a velocity 10(9) cm/s, during the laser pulse. In contrast, a material-vapor plume forms approximately 200 ps after the laser pulse, and it moves away from the target at 10(6) cm/s. The experimental observations of the early-stage plasma were simulated by using a theoretical model based on a two-fluids description of laser plasmas. The results indicate that the initiation of the plasma is due to air breakdown assisted by electron emission from the target. (C) 2000 American Institute of Physics. [S0003-6951(00)01342-5]. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Russo, RE (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. NR 24 TC 88 Z9 88 U1 1 U2 9 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 OCT 16 PY 2000 VL 77 IS 16 BP 2464 EP 2466 DI 10.1063/1.1318239 PG 3 WC Physics, Applied SC Physics GA 362HK UT WOS:000089772400010 ER PT J AU Kwon, HK Eiting, CJ Lambert, DJH Wong, MM Dupuis, RD Liliental-Weber, Z Benamara, M AF Kwon, HK Eiting, CJ Lambert, DJH Wong, MM Dupuis, RD Liliental-Weber, Z Benamara, M TI Observation of long photoluminescence decay times for high-quality GaN grown by metalorganic chemical vapor deposition SO APPLIED PHYSICS LETTERS LA English DT Article ID DONOR-BOUND EXCITON; RECOMBINATION; EPITAXY AB GaN epitaxial layers with different crystalline quality grown on sapphire substrates by metalorganic chemical vapor deposition are investigated using time-resolved photoluminescence at 300 K. It is found that the time-dependent photoluminescence of low-quality GaN decays faster than that of the high-quality GaN films. The time constants for the dual-exponential decay of the photoluminescence are calculated to be 50 and 250 ps for high-quality undoped GaN and 30 ps for low-quality undoped GaN. For high-quality Si-doped GaN, time constants of 150 and 740 ps are extracted while corresponding time constants of 40 and 200 ps are measured for low-quality Si-doped GaN. We believe that the time constant of 740 ps measured for our high-quality Si-doped GaN is the longest ever reported for thin GaN/sapphire films. (C) 2000 American Institute of Physics. [S0003- 6951(00)01942-2]. C1 Univ Texas, Microelect Res Ctr, Austin, TX 78712 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Dupuis, RD (reprint author), Univ Texas, Microelect Res Ctr, PRC MER 1-606D-R9900, Austin, TX 78712 USA. RI Liliental-Weber, Zuzanna/H-8006-2012 NR 11 TC 25 Z9 25 U1 1 U2 3 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 OCT 16 PY 2000 VL 77 IS 16 BP 2503 EP 2505 DI 10.1063/1.1318396 PG 3 WC Physics, Applied SC Physics GA 362HK UT WOS:000089772400023 ER PT J AU Ford, JV Sumpter, BG Noid, DW Barnes, MD Otaigbe, JU AF Ford, JV Sumpter, BG Noid, DW Barnes, MD Otaigbe, JU TI Refractive index dispersion functions of solid-phase polymers by multicolor optical diffraction SO APPLIED PHYSICS LETTERS LA English DT Article ID SIZE; ELECTROLUMINESCENCE; SCATTERING; DROPLETS; BLEND AB We show that fourth-order dispersion functions of solid-phase polymers can be determined by multicolor optical diffraction. Electrodynamically trapped microparticles of polyethylene glycol with different molecular weights were probed by two-dimensional optical diffraction with four different laser wavelengths (632.8, 514.5, 488.0, and 457.9 nm); subsequent Mie analysis of one-dimensional scattering patterns yielded size and refractive index (both real and imaginary parts). Using a single wavelength as a size reference, the nonlinear dependence of the refractive index of solid (nonevaporating) polymer microparticles was determined by finding the refractive index for a given wavelength that best matched a Mie calculation subject to the reference size constraint. The experimentally determined refractive index values were fit to a standard fourth-order Cauchy function to obtain values for n(0), n(1), and n(2). (C) 2000 American Institute of Physics. [S0003-6951(00)04142-5]. C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. Iowa State Univ, Dept Mat Sci & Engn, Ames, IA 50011 USA. RP Barnes, MD (reprint author), Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RI Sumpter, Bobby/C-9459-2013 OI Sumpter, Bobby/0000-0001-6341-0355 NR 18 TC 10 Z9 10 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 OCT 16 PY 2000 VL 77 IS 16 BP 2515 EP 2517 AR PII [S0003-6951(00)04142-5] DI 10.1063/1.1318940 PG 3 WC Physics, Applied SC Physics GA 362HK UT WOS:000089772400027 ER PT J AU Chanana, RK McDonald, K Di Ventra, M Pantelides, ST Feldman, LC Chung, GY Tin, CC Williams, JR Weller, RA AF Chanana, RK McDonald, K Di Ventra, M Pantelides, ST Feldman, LC Chung, GY Tin, CC Williams, JR Weller, RA TI Fowler-Nordheim hole tunneling in p-SiC/SiO2 structures SO APPLIED PHYSICS LETTERS LA English DT Article ID SILICON DIOXIDE; TRANSPORT; SUBSTRATE AB We report the confirmed occurrence of Fowler-Nordheim hole tunneling in p-4H-SiC metal-oxide-semiconductor capacitor structures. The effective mass for holes in the oxide is found to be in the range of 0.35m-0.52m, where m is the free electron mass. (C) 2000 American Institute of Physics. [S0003-6951(00)00342-9]. C1 Vanderbilt Univ, Dept Phys & Astron, Nashville, TN 37235 USA. Auburn Univ, Dept Phys, Auburn, AL 36801 USA. Vanderbilt Univ, Dept Elect Engn & Comp Sci, Nashville, TN 37235 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Chanana, RK (reprint author), Vanderbilt Univ, Dept Phys & Astron, Nashville, TN 37235 USA. RI Di Ventra, Massimiliano/E-1667-2011; Tin, Chin-Che/A-9122-2012 OI Di Ventra, Massimiliano/0000-0001-9416-189X; NR 15 TC 47 Z9 48 U1 0 U2 10 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 OCT 16 PY 2000 VL 77 IS 16 BP 2560 EP 2562 DI 10.1063/1.1318229 PG 3 WC Physics, Applied SC Physics GA 362HK UT WOS:000089772400042 ER PT J AU Park, BH Gim, Y Fan, Y Jia, QX Lu, P AF Park, BH Gim, Y Fan, Y Jia, QX Lu, P TI High nonlinearity of Ba0.6Sr0.4TiO3 films heteroepitaxially grown on MgO substrates SO APPLIED PHYSICS LETTERS LA English DT Article ID BARIUM STRONTIUM-TITANATE; THIN-FILMS; MICROWAVE PROPERTIES AB We have heteroepitaxially deposited Ba0.6Sr0.4TiO3 (BST) thin films on (001)-oriented MgO substrates using pulsed-laser deposition. By optimizing the deposition temperature and adjusting the film thickness, we have successfully increased the dielectric nonlinearity and decreased the dielectric loss of BST films. BST thin films grown at 750 degrees C with a thickness of 1.1 mu m showed a dielectric constant tunability of greater than 65% and a tunability/loss of 43 at a surface electric field of 80 kV/cm at room temperature. X-ray diffraction and transmission electron microscopy analyses indicated that the tunability and dielectric loss were closely related to the crystallinity of the BST films. (C) 2000 American Institute of Physics. [S0003-6951(00)00742-7]. C1 Univ Calif Los Alamos Natl Lab, Superconduct Technol Ctr, Los Alamos, NM 87545 USA. New Mexico Tech, Dept Mat Sci & Engn, Socorro, NM 87801 USA. RP Park, BH (reprint author), Univ Calif Los Alamos Natl Lab, Superconduct Technol Ctr, Mail Stop K763, Los Alamos, NM 87545 USA. RI Park, Bae Ho/D-4840-2011; Jia, Q. X./C-5194-2008 NR 14 TC 106 Z9 110 U1 1 U2 8 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 OCT 16 PY 2000 VL 77 IS 16 BP 2587 EP 2589 DI 10.1063/1.1318233 PG 3 WC Physics, Applied SC Physics GA 362HK UT WOS:000089772400051 ER PT J AU Im, J Streiffer, SK Auciello, O Krauss, AR AF Im, J Streiffer, SK Auciello, O Krauss, AR TI (BaxSr1-x)Ti1+yO3+z interface contamination and its effect on electrical properties SO APPLIED PHYSICS LETTERS LA English DT Article ID CHEMICAL-VAPOR-DEPOSITION; THIN-FILMS; DIELECTRIC RESPONSE; IN-SITU; BA0.7SR0.3TIO3 AB Surface contamination and cleaning processes of (BaxSr1-x)Ti1+yO3+z(BST) and Pt films were investigated using in situ, real-time mass spectroscopy of recoiled ions (MSRI). MSRI analysis revealed that BST film surfaces exposed to atmospheric ambient are contaminated with carbon and hydrogen containing species, which could be removed by thermal decomposition/desorption in an oxygen ambient. Cleaning of the BST surface was accomplished by annealing at 500 degrees C in greater than or equal to 1 mTorr O-2, resulting in complete elimination of these species. Similar contamination on Pt film surfaces could be eliminated with only 200 degrees C annealing in 5 x 10(-4) Torr of O-2. Annealing of the BST film surface in oxygen prior to deposition of the top Pt electrode results in a clean top Pt/BST interface that yields BST capacitors with much lower and more symmetric leakage current characteristics, and lower dielectric losses compared to BST capacitors with contaminated top Pt electrode/BST interfaces. (C) 2000 American Institute of Physics.[S0003-6951(00)02942-9]. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Argonne Natl Lab, Div Mat & Chem Sci, Argonne, IL 60439 USA. RP Im, J (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Streiffer, Stephen/A-1756-2009 NR 11 TC 33 Z9 34 U1 0 U2 3 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 OCT 16 PY 2000 VL 77 IS 16 BP 2593 EP 2595 DI 10.1063/1.1318730 PG 3 WC Physics, Applied SC Physics GA 362HK UT WOS:000089772400053 ER PT J AU Siriwardane, RV Poston, JA Fisher, EP Lee, TH Dorris, SE Balachandran, U AF Siriwardane, RV Poston, JA Fisher, EP Lee, TH Dorris, SE Balachandran, U TI Characterization of ceramic hydrogen separation membranes with varying nickel concentrations SO APPLIED SURFACE SCIENCE LA English DT Article DE high temperature membranes; hydrogen separation membranes; ceramic membranes; surface characterization of membranes ID SCANNING ELECTRON-MICROSCOPY AB Ceramic hydrogen separation membranes in the stoichiometric form BaCe0.8Y0.2O3, doped with various concentrations of nickel, were characterized by utilizing X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and atomic-force microscopy (AFM). Characterization was performed at room temperature, 550 degrees C and 650 degrees C, and after exposure to hydrogen. Migration of nickel to the surface and changes in both elemental composition and oxidation states were observed at elevated temperatures. The concentration of nickel significantly affects surface morphology and roughness. (C) 2000 Published by Elsevier Science B.V. C1 US Dept Energy, Natl Energy Technol Lab, Morgantown, WV 26507 USA. Argonne Natl Lab, Div Energy Technol, Argonne, IL 60439 USA. RP Siriwardane, RV (reprint author), US Dept Energy, Natl Energy Technol Lab, 3610 Collins Ferry Rd, Morgantown, WV 26507 USA. NR 11 TC 23 Z9 24 U1 1 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0169-4332 J9 APPL SURF SCI JI Appl. Surf. Sci. PD OCT 16 PY 2000 VL 167 IS 1-2 BP 34 EP 50 DI 10.1016/S0169-4332(00)00493-1 PG 17 WC Chemistry, Physical; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Chemistry; Materials Science; Physics GA 355TL UT WOS:000089402400004 ER PT J AU Lente, G Espenson, JH AF Lente, G Espenson, JH TI Kinetics and mechanism of oxygen transfer to methyloxo(dithiolato)rhenium(V) complexes SO INORGANIC CHEMISTRY LA English DT Article ID ATOM-TRANSFER-REACTIONS; MAIN-GROUP ELEMENTS; TRANSITION-METALS; MULTIPLE BONDS; METHYLTRIOXORHENIUM(VII); ALKYLRHENIUM; RHENIUM(V) AB The kinetics and mechanism of the reactions of the dimeric and monomeric methyloxo(dithiolato)rhenium(V) complexes [(o-SC6H4CH2S)Re(O)CH3](2) and [(o-SC6H4CH2S)PyRe(O)CH3] (Py = pyridine) with XO, sulfoxides, and pyridine N-oxides are studied. In these reactions, an oxygen atom from XO is transferred to rhenium, from which it later removed. A reaction scheme is proposed to interpret the kinetic data. This scheme features the formation of a monomeric (sulfoxide)- or (pyridine N-oxide)(dithiolato)methyloxorhenium(V) complex followed by its bimolecular oxidation in a rate-controlling step. Several sulfoxides (methyl, methyl phenyl, and substituted diphenyl) all react at similar rates. Activation parameters are determined for dimethyl sulfoxide and di-4-tolyl sulfoxide from temperature-dependent studies. The reactions with pyridine N-oxides show autocatalysis in which the catalyst is confirmed to be pyridine formed in the reactions. 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. RI Lente, Gabor/H-3645-2011 NR 20 TC 17 Z9 17 U1 0 U2 7 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 OCT 16 PY 2000 VL 39 IS 21 BP 4809 EP 4814 DI 10.1021/ic000148j PG 6 WC Chemistry, Inorganic & Nuclear SC Chemistry GA 365RT UT WOS:000089964800021 PM 11196958 ER PT J AU Rapko, BM McNamara, BK Rogers, RD Broker, GA Lumetta, GJ Hay, BP AF Rapko, BM McNamara, BK Rogers, RD Broker, GA Lumetta, GJ Hay, BP TI Coordination of lanthanide triflates and perchlorates with N,N,N ',N '-tetramethylsuccinamide SO INORGANIC CHEMISTRY LA English DT Article ID METAL-AMIDE COMPLEXES; EXTRACTION; TETRAHEXYLMALONAMIDES; MALONAMIDE; ION AB Compounds formed from the reaction of N,N,N,N-tetramethylsuccinamide (TMSA) with trivalent lanthanide salts possessing the poorly coordinating counteranions triflate (CF3SO3-) and perchlorate (ClO4-) have been prepared and examined. Structural features of these Ln-TMSA compounds have been studied in the solid phase by thermogravimetric analysis, infrared spectroscopy, and, in selected cases, by single-crystal X-ray diffraction and in solution by infrared spectroscopy. Eight-coordinate compounds, [Ln(TMSA)(4)](3+), derived from coordination of four succinamide ligands to the metal ion could be formed with all lanthanides examined (Ln = La,Pr,Nd, Eu, Yb, Lu). Structural analyses by single-crystal X-ray diffraction were performed for the lanthanide triflate salts Ln(C8H16N2O2)(4)(CF3SO3)(3): Ln = La, compound 1, monoclinic, P2(1)/n, a = 11.0952623 Angstrom, b = 19.2672(2) Angstrom, c = 24.9759(3) Angstrom, beta = 90.637(1)degrees Z = 4, D-calcd = 1.586 g cm(-3); Ln = Nd, compound 2, monoclinic, C2/c, a = 24.6586(10) Angstrom, b = 19.3078(7) Angstrom, c = 11.1429(4) Angstrom, beta = 90.450(1)degrees, Z = 4, D-calcd = 1.603 g cm(-3); Ln = Eu, compound 3, monoclinic, C2/c, a = 24.4934(2) Angstrom, b = 119.3702(1) Angstrom, c = 11.1542(1) Angstrom, beta = 90.229(1)degrees Z = 4, D-calcd = 1.617 g cm(-3); Ln = Lu, compound 5, monoclinic, C2/c, a = 24.2435(4) Angstrom, b = 19.6141(2) Angstrom, c = 11.2635(1) Angstrom, beta = 90.049(1)degrees Z = 4, D-calcd = 1.626 g cm(-3). X-ray analysis was also carried out for the perchlorate salt: Ln = Eu, compound 4, triclinic, P1, a = 10.9611(2) Angstrom, b = 14.6144(3) Angstrom, c = 15.7992(2) Angstrom, a = 106.594(1)degrees, beta = 91.538(1)degrees gamma = 90.311(1)degrees Z = 2, D-calcd = 1.561 g cm(-3). In the presence of significant amounts of water, 7-coordinate compounds with mixed aquo-TMSA cation structures [Ln(TMSA)(3)(H2O)(3+) (Ln = Yb)] and [Ln(TMSA)(2)(H2O)(3)](3+) (Ln = La, Pr, Nd, Eu, Yb) have been isolated with structural determinations by single-crystal X-ray diffraction obtained for the following species: Yb(C8H16N2O2)(3)(H2O)(CF3SO3)(3), compound 6, monoclinic, P2(1)/n, a = 8.9443(3) Angstrom, b = 11.1924(4) Angstrom, c = 44.2511(13) Angstrom, beta = 93.264(1)degrees, Z = 4, D-calcd = 1.735 g cm(-3); Yb(C8H16N2O2)(3)(H2O)(ClO4)(3), compound 7, monoclinic, Cc, a = 19.2312(6) Angstrom, b = 11.1552(3) Angstrom, c = 19.8016(4) Angstrom, beta = 111.4260(1)degrees, Z = 4, D-calcd = 1.690 g cm(-3); Yb(C8H16N2O2)(2)(H2O)(3)(CF3SO3)(3), compound 8, triclinic, P1, a = 8.6719(1) Angstrom, b = 12.2683(2) Angstrom, c = 19.8094(3) Angstrom, alpha = 75.815(1)degrees, beta = 86.805(1)degrees, gamma = 72.607(1)degrees Z = 2, D-calcd = 1.736 g cm(-3). Unlike in the analogous nitrate salts, only bidentate binding of the succinamide ligand to the lanthanide metal is observed. IR spectroscopy studies in anhydrous acetonitrile suggest that the solid-state structures of these Ln-TMSA compounds are maintained in solution. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. Univ Alabama, Dept Chem, Tuscaloosa, AL 35487 USA. RP Rapko, BM (reprint author), Pacific NW Natl Lab, POB 999, Richland, WA 99352 USA. EM brian.rapko@pnl.gov RI Rogers, Robin/C-8265-2013 OI Rogers, Robin/0000-0001-9843-7494 NR 23 TC 6 Z9 6 U1 1 U2 7 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 OCT 16 PY 2000 VL 39 IS 21 BP 4858 EP 4867 DI 10.1021/ic000244k PG 10 WC Chemistry, Inorganic & Nuclear SC Chemistry GA 365RT UT WOS:000089964800028 PM 11196965 ER PT J AU Gibson, JK AF Gibson, JK TI Reactions of actinide ions with pentamethylcyclopentadiene: atypical hydrocarbon activation SO INTERNATIONAL JOURNAL OF MASS SPECTROMETRY LA English DT Article DE actinides; transuranics; pentamethylcyclopentadiene; dehydrogenation; americium ID GAS-PHASE CHEMISTRY; ORGANOMETALLIC CHEMISTRY; CYCLIC HYDROCARBONS; LANTHANIDE CATIONS; ALKENES; REACTIVITY; COMPLEXES; LN(+); METAL; SC+ AB Gas-phase reactions of 1,2,3,4,5-pentamethylcyclopentadiene (HCp*) with three actinide ions, Np+, Pu+, and Am+, were studied by laser ablation mass spectrometry. The primary goal was to determine if an unusual, non-insertion mode of C-H activation reported for lanthanide ions, Ln(+), with this substrate obtains for the homologous actinide ions; the Cp* ligand is central in organoactinide chemistry and the interaction of the quasivalence 5f electrons with HCp* is of special interest. It was found that Np+ and Pu+ behave similarly to the "reactive" Ln(+), and that Am+ is similar to the "inert" group of Ln(+). For bath Ln(+) and An(+), reactivity appears to reflect the energy necessary to excite the ground state metal ion to a configuration with two non-f valence electrons. Evidently Am+, which exhibits a large excitation energy, comparable to those of the inert Ln(+) induces C-H activation and single-H-2-elimination from HCp* by a non-insertion process not seen with other alkenes; this lanthanide-like behavior suggests no distinctive role of the 5f electrons in the Am+-HCp* interaction. Activation by Np+ and Pu+ of the methyl groups of a tetramethylfulvene intermediate results in double- and triple-dehydrogenation which evidently proceeds by a conventional insertion process involving a C-An(+)-H complex, in accord with the relatively small Np+ and Pu+ excitation energies. Results for reactions of AnO(+) with HCp* revealed an enhanced dehydrogenation activity of NpO+ compared with LnO(+), which may be a result of the greater accessibility of high oxidation states at the Np metal center. (Int J Mass Spectrom 202 (2000) 19-29) (C) 2000 Elsevier Science B.V. C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Gibson, JK (reprint author), Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. NR 25 TC 8 Z9 8 U1 1 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 1387-3806 J9 INT J MASS SPECTROM JI Int. J. Mass Spectrom. PD OCT 16 PY 2000 VL 202 IS 1-3 BP 19 EP 29 DI 10.1016/S1387-3806(00)00203-7 PG 11 WC Physics, Atomic, Molecular & Chemical; Spectroscopy SC Physics; Spectroscopy GA 367VH UT WOS:000090081800005 ER PT J AU Blaum, K Geppert, C Muller, P Nortershauser, W Wendt, K Bushaw, BA AF Blaum, K Geppert, C Muller, P Nortershauser, W Wendt, K Bushaw, BA TI Peak shape for a quadrupole mass spectrometer: comparison of computer simulation and experiment SO INTERNATIONAL JOURNAL OF MASS SPECTROMETRY LA English DT Article DE quadrupole mass filter; ion energy distribution; ion trajectory calculations; isotopic abundance sensitivity; peak shape ID RF-ONLY QUADRUPOLES; FRINGING FIELDS; FILTER; ACCEPTANCE AB Computer simulations of ion trajectories have been used to evaluate the performance of a quadrupole mass spectrometer. Consideration has been given to realistic fields modeled on a commercial system as well as experimental distributions with respect to ion entry position, axial and radial velocity and relative phase of the quadrupole field. Determination of the mass filter acceptance-area as a function of the mass setting yields mass peak shapes with a dynamic range of more than seven orders of magnitude and thus provides estimates for abundance sensitivity. Results from these simulations are found to give excellent agreement with experimental measurements for different elements in a wide mass range of 6 less than or equal to A less than or equal to 160. Further, conventional Monte Carlo simulations give insight into subtle effects resulting in a substructure on the top of the mass peak and allows the determination of the energy spread of the initial ion ensemble. (Int J Mass Spectrom 202 (2000) 81-89) (C) 2000 Elsevier Science B.V. C1 Univ Mainz, Inst Phys, D-55099 Mainz, Germany. Pacific NW Natl Lab, Richland, WA 99352 USA. RP Blaum, K (reprint author), Univ Mainz, Inst Phys, D-55099 Mainz, Germany. RI Mueller, Peter/E-4408-2011; Wendt, Klaus/D-7306-2011; Nortershauser, Wilfried/A-6671-2013 OI Mueller, Peter/0000-0002-8544-8191; Wendt, Klaus/0000-0002-9033-9336; Nortershauser, Wilfried/0000-0001-7432-3687 NR 20 TC 17 Z9 18 U1 0 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 1387-3806 J9 INT J MASS SPECTROM JI Int. J. Mass Spectrom. PD OCT 16 PY 2000 VL 202 IS 1-3 BP 81 EP 89 DI 10.1016/S1387-3806(00)00237-2 PG 9 WC Physics, Atomic, Molecular & Chemical; Spectroscopy SC Physics; Spectroscopy GA 367VH UT WOS:000090081800011 ER PT J AU Schaaff, TG Stephenson, JL McLuckey, SA AF Schaaff, TG Stephenson, JL McLuckey, SA TI Reactions of angiotensin ions with hydroiodic acid SO INTERNATIONAL JOURNAL OF MASS SPECTROMETRY LA English DT Article DE angiotensin ions; hydroiodic acid attachment; quadrupole ion trap ID SURFACE-INDUCED DISSOCIATION; PHASE HYDROGEN/DEUTERIUM EXCHANGE; PROTON-TRANSFER REACTIONS; TANDEM MASS-SPECTROMETRY; CYTOCHROME-C IONS; GAS-PHASE; ELECTROSPRAY-IONIZATION; PEPTIDE IONS; DIELECTRIC POLARIZABILITY; DEUTERIUM-EXCHANGE AB The kinetics of HI attachment to gaseous angiotensin-related ions were determined in a quadrupole ion trap mass spectrometer. The (M + H)(+) and (M + 2H)(2+) ions of peptides with sequences of DRVYIHPFHL, NRVTVHPFHL, and RVYIHPFHL and the (M + H)(+) ions of DRVYIHPF and NRVYVHPF and their respective methyl esters were studied. For many of the ions studied here, multiple reactive conformations were resolved by their differing reactivities. The kinetics of the attachment of HI to the singly charged ions are consistent with structural models that are generated by molecular mechanics calculations, which suggest a high degree of intraionic interactions between the protonation site and other basic sites in the ion. The incorporation of HI can also disrupt the inherent intraionic interactions in the ions, which is not only reflected in the reaction kinetics, but also consistent with the interactions suggested by the molecular mechanics simulations. These results confirm that HI attachment kinetics can be used as a probe of three dimensional ion structure and provide important new information regarding the utility of this molecular probe. (Int J Mass Spectrom 202 (2000) 299-313) (C) 2000 Elsevier Science B.V. C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP McLuckey, SA (reprint author), Purdue Univ, Brown Lab 1393, W Lafayette, IN 47907 USA. RI Stephenson, James/A-9262-2009; McLuckey, Scott/B-2203-2009 OI McLuckey, Scott/0000-0002-1648-5570 NR 53 TC 3 Z9 3 U1 1 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 1387-3806 J9 INT J MASS SPECTROM JI Int. J. Mass Spectrom. PD OCT 16 PY 2000 VL 202 IS 1-3 BP 299 EP 313 DI 10.1016/S1387-3806(00)00255-4 PG 15 WC Physics, Atomic, Molecular & Chemical; Spectroscopy SC Physics; Spectroscopy GA 367VH UT WOS:000090081800028 ER PT J AU Cohen, RC Perkins, KK Koch, LC Stimpfle, RM Wennberg, PO Hanisco, TF Lanzendorf, EJ Bonne, GP Voss, PB Salawitch, RJ Del Negro, LA Wilson, JC McElroy, CT Bui, TP AF Cohen, RC Perkins, KK Koch, LC Stimpfle, RM Wennberg, PO Hanisco, TF Lanzendorf, EJ Bonne, GP Voss, PB Salawitch, RJ Del Negro, LA Wilson, JC McElroy, CT Bui, TP TI Quantitative constraints on the atmospheric chemistry of nitrogen oxides: An analysis along chemical coordinates SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID IN-SITU MEASUREMENTS; INDUCED FLUORESCENCE INSTRUMENT; DIODE-LASER SPECTROMETER; NASA ER-2 AIRCRAFT; LOWER STRATOSPHERE; REACTIVE NITROGEN; SULFATE AEROSOLS; 2-DIMENSIONAL MODEL; INSITU MEASUREMENTS; OZONE DEPLETION AB In situ observations of NO2, NO, NOy, ClONO2, OH, O-3, aerosol surface area, spectrally resolved solar radiation, pressure and temperature obtained from the ER-2 aircraft during the Photochemistry of Ozone Loss in the Arctic Region in Summer (POLARIS) experiments are used to examine the factors controlling the fast photochemistry connecting NO and NO2 and the slower chemistry connecting NOx and HNO3. Our analysis uses "chemical coordinates" to examine gradients of the difference between a model and precisely calibrated measurements to provide a quantitative assessment of the accuracy of current photochemical models. The NO/NO2 analysis suggests that reducing the activation energy for the NO+O-3 reaction by 1.7 kJ/mol will improve model representation of the temperature dependence of the NO/NO2 ratio in the range 215-235 K. The NOx/HNO3 analysis shows that systematic errors in the relative rate coefficients used to describe NOx loss by the reaction OH + NO2 --> HNO3 and by the reaction set NO2+O-3-->NO3; NO2+NO3 --> N2O5; N2O5+H2O --> 2HNO(3) are in error by +8.4% (+30/-45%) (OH + NO2 too fast) in models using the Jet Propulsion Laboratory 1997 recommendations [DeMore et al., 1997]. Models that use recommendations for OH+NO2 and OH+HNO3 based on reanalysis of recent and past laboratory measurements are in error by 1.2% (+30/-45%) (OH + NO2 too slow). The +30%/-45% error limit reflects systematic uncertainties, while the statistical uncertainty is 0.65%. This analysis also shows that the POLARIS observations only modestly constrain the relative rates of the major NOx production reactions HNO3 + OH --> H2O + NO3 and HNO3 + hv --> OH + NO2. Even under the assumption that all other aspects of the model are perfect, the POLARIS observations only constrain the rate coefficient for OH+HNO3 to a range of 65% around the currently recommended value. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Earth & Planetary Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Energy & Environm, Berkeley, CA 94720 USA. Harvard Univ, Dept Chem & Biol Chem, Cambridge, MA 02138 USA. Harvard Univ, Dept Earth & Planetary Sci, Cambridge, MA 02138 USA. Univ Colorado, Dept Chem, Boulder, CO 80309 USA. CALTECH, Div Geol & Planetary Sci, Pasadena, CA 91125 USA. CALTECH, Div Engn, Pasadena, CA 91125 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91125 USA. NOAA, Aeron Lab, Boulder, CO 80303 USA. Univ Denver, Dept Mech Engn, Denver, CO 80208 USA. Environm Canada, Downsview, ON M3H 5T4, Canada. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Cohen, RC (reprint author), Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. EM cohen@cchem.berkeley.edu RI Salawitch, Ross/B-4605-2009; Cohen, Ronald/A-8842-2011; Wennberg, Paul/A-5460-2012 OI Salawitch, Ross/0000-0001-8597-5832; Cohen, Ronald/0000-0001-6617-7691; NR 80 TC 15 Z9 15 U1 0 U2 7 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD OCT 16 PY 2000 VL 105 IS D19 BP 24283 EP 24304 DI 10.1029/2000JD900290 PG 22 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 366WM UT WOS:000090029300008 ER PT J AU Chen, YL Lewis, JWL Parigger, C AF Chen, YL Lewis, JWL Parigger, C TI Spatial and temporal profiles of pulsed laser-induced air plasma emissions SO JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER LA English DT Article DE optical breakdown; plasma; laser; air breakdown ID BREAKDOWN AB The laser-induced breakdown and energy deposition in air were studied using a full-width at half-maximum (FWHM) 6.5-ns pulse Nd:YAG laser. For the non-resonant breakdowns, two-dimensional spontaneous emission images were obtained with nanosecond resolution from breakdown to 10 times the FWHM of the pulse of the spatial and temporal variations of the energy deposition and plasma formation processes. The spatial emission features are compared with the predictions of the laser irradiance in the focal region that results from the focus lens aberrations. The statistical variation of the absorbed energy was determined over the energy range from below-to-approximately six times the breakdown threshold. Comparisons are made of the measured plasma wave speed with one-dimensional laser-supported radiation wave predictions. (C) 2000 Elsevier Science Ltd. All rights reserved. C1 Univ Tennessee, Inst Space, Ctr Laser Applicat, Tullahoma, TN 37388 USA. RP Chen, YL (reprint author), Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA. RI Parigger, Christian/M-4925-2013 OI Parigger, Christian/0000-0003-1286-7405 NR 19 TC 96 Z9 99 U1 3 U2 19 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 OCT 16 PY 2000 VL 67 IS 2 BP 91 EP 103 DI 10.1016/S0022-4073(99)00196-X PG 13 WC Optics; Spectroscopy SC Optics; Spectroscopy GA 331RX UT WOS:000088033400001 ER PT J AU Logan, HE Nierste, U AF Logan, HE Nierste, U TI B-s,B-d -> e(+)e(-) in a two-Higgs-doublet model SO NUCLEAR PHYSICS B LA English DT Article DE B, leptonic decay; Higgs particle, multiplet; Higgs particle, mass ID LARGE TAN-BETA; NEUTRAL CURRENTS; QCD CORRECTIONS; STANDARD MODEL; QUARK MASS; DECAY; RENORMALIZATION; CONSERVATION; LEPTONS AB We compute the branching fractions of B-s,B-d --> e(+)e(-) in the type-II two-Higgs-doublet model with large tan beta. We find that the parameters of the neutral Higgs sector of the two-Higgs-doublet model cancel in the result, so that the branching fractions depend only on the charged Higgs mass and tan beta. For large values of tan beta and a charged Higgs mass above the bound from b --> s gamma, we find that the branching fractions can be enhanced by up to an order of magnitude or suppressed by up to a factor of two compared to the Standard Model result. We point out that previous calculations in the literature are gauge-dependent due to the omission of an important diagram, which gives the dominant contribution in the 't Hooft-Feynman gauge. We have analyzed in detail the region of the (M-H+, tan beta) plane to be probed by searches for B-s --> mu(+)mu(-) in Run II of the Tevatron. Since the branching fraction increases like tan(4) beta, this decay mode is complementary to b --> s gamma and efficiently probes the large tan beta region. For tan beta = 60, an integrated luminosity of 20 fb(-1) in an extended Run II will probe charged Higgs masses up to 260 GeV, if the background to B-s --> mu(+)mu(-) is small. For the same value of tan beta, the LHC may be able to explore charged Higgs masses up to 1 TeV using this decay. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Fermilab, Dept Theoret Phys, Batavia, IL 60510 USA. RP Logan, HE (reprint author), Fermilab, Dept Theoret Phys, Batavia, IL 60510 USA. NR 36 TC 99 Z9 100 U1 0 U2 0 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 OCT 16 PY 2000 VL 586 IS 1-2 BP 39 EP 55 DI 10.1016/S0550-3213(00)00417-X PG 17 WC Physics, Particles & Fields SC Physics GA 361UE UT WOS:000089741900002 ER PT J AU Chetyrkin, KG Harlander, RV Kuhn, JH AF Chetyrkin, KG Harlander, RV Kuhn, JH TI Quartic mass corrections to R-had at O(alpha(3)(s)) SO NUCLEAR PHYSICS B LA English DT Article ID Z-DECAY RATE; QUANTUM-CHROMODYNAMIC CORRECTIONS; E+E ANNIHILATION; O(ALPHA(2)(S)) CORRECTIONS; ORDER; R(HAD); POLARIZATION; ALPHA(3)(S); CORRELATOR; LIMIT AB The total cross section for the production of massive quarks in electron-positron annihilation can be predicted in perturbative QCD. After expansion in m(2)/s the quartic terms, i.e., those proportional to m(4)/s(2) are calculated up to order alpha(s)(3) for vector and axial current induced rates. predictions relevant for charm, bottom and top quarks production are presented. The alpha(s)(3) corrections are shown to be comparable to terms of order alpha(s) and alpha(s)(2). As a consequence, the predictions exhibit a sizeable dependence on the renormalization scale. The stability of the prediction is improved and, at the same time, the relative size of the large order terms decreases by replacing the running mass (m) over bar(mu) with the scheme independent invariant one (m) over cap. By combining these results with the prediction for massless case and the quadratic mass terms the cross section for massive quark production at electron-positron colliders is put under control in order alpha(s)(3) From the high energy region down to fairly low energies. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. Univ Karlsruhe, Inst Theoret Teilchenphys, D-76128 Karlsruhe, Germany. RP Harlander, RV (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. NR 36 TC 44 Z9 45 U1 0 U2 0 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 OCT 16 PY 2000 VL 586 IS 1-2 BP 56 EP 72 DI 10.1016/S0550-3213(00)00393-X PG 17 WC Physics, Particles & Fields SC Physics GA 361UE UT WOS:000089741900003 ER PT J AU Carena, M Ellis, J Pilaftsis, A Wagner, CEM AF Carena, M Ellis, J Pilaftsis, A Wagner, CEM TI Renormalization-group-improved effective potential for the MSSM Higgs sector with explicit CP violation SO NUCLEAR PHYSICS B LA English DT Review ID SUPERSYMMETRIC STANDARD MODEL; ELECTRIC-DIPOLE MOMENTS; ELECTROWEAK PHASE-TRANSITION; WEAK BOSON FUSION; RADIATIVE-CORRECTIONS; EXPERIMENTAL LIMIT; QCD CORRECTIONS; ANOMALOUS U(1); NEUTRAL KAON; SOFT PHASES AB We perform a systematic study of the one-loop renormalization-group-improved effective potential of the minimal supersymmetric extension of the Standard Model (MSSM), including CP violation induced radiatively by soft trilinear interactions related to squarks of the third generation. We calculate the charged and neutral Higgs-boson masses and couplings, including the two-loop logarithmic corrections that arise from QCD effects, as well as those associated with the top- and bottom-quark Yukawa couplings. We also include the potentially large two-loop non-logarithmic corrections induced by one-loop threshold effects on the top- and bottom-quark Yukawa couplings, due to the decoupling of the third-generation squarks. Within this minimal CP-violating framework, the charged and neutral Higgs sectors become intimately related to one another and therefore require a unified treatment. In the limit of a large charged Higgs-boson mass, M-H+/- much greater than M-Z. the lightest neutral Higgs boson resembles that in the Standard Model (SM), and CP violation occurs only in the heavy Higgs sector. Our analysis shows that sizeable radiative effects of CP violation in the Higgs sector of the MSSM may lead to significant modifications of previous studies for Higgs-boson searches at LEP 2, the Tevatron and the LHC. In particular, CP violation could enable a relatively light Higgs boson to escape detection at LEP 2. (C) 2000 Elsevier Science B.V. All rights reserved. C1 CERN, Div Theory, CH-1211 Geneva 23, Switzerland. Fermilab, Batavia, IL 60510 USA. Argonne Natl Lab, Div High Energy Phys, Argonne, IL 60439 USA. Univ Chicago, Enrico Fermi Inst, Chicago, IL 60637 USA. RP Pilaftsis, A (reprint author), CERN, Div Theory, CH-1211 Geneva 23, Switzerland. NR 148 TC 262 Z9 263 U1 0 U2 3 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 OCT 16 PY 2000 VL 586 IS 1-2 BP 92 EP 140 DI 10.1016/S0550-3213(00)00358-8 PG 49 WC Physics, Particles & Fields SC Physics GA 361UE UT WOS:000089741900005 ER PT J AU Fang, XG Scott, BL Watkin, JG Kubas, GJ AF Fang, XG Scott, BL Watkin, JG Kubas, GJ TI C-H and Si-H activation on palladium(II) and platinum(II) complexes with a new methoxyalkyl-substituted diimine ligand SO ORGANOMETALLICS LA English DT Article ID ALPHA-OLEFINS; POLYMERIZATION; ETHYLENE; ETA(2)-SILANE; CATALYSTS; CLEAVAGE; STYRENE; BOND AB Electrophilic 1,4-bis(methoxypropyl)-2,3-dimethyl-1,4-diazabutadiene Pd(II)) and Pt(II) cations 2a, b with a BArF counteranion, have been prepared. Complex 2a undergoes intramolecular C-H activation to form tricyclic 5, and complex 2b adds to Et3SiH to form an octahedral diimine Pt(IV) silyl hydride complex, 7. C1 Univ Calif Los Alamos Natl Lab, Div Chem, Los Alamos, NM 87545 USA. RP Kubas, GJ (reprint author), Univ Calif Los Alamos Natl Lab, Div Chem, MS J514, Los Alamos, NM 87545 USA. RI Scott, Brian/D-8995-2017 OI Scott, Brian/0000-0003-0468-5396 NR 27 TC 52 Z9 52 U1 1 U2 8 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0276-7333 J9 ORGANOMETALLICS JI Organometallics PD OCT 16 PY 2000 VL 19 IS 21 BP 4193 EP 4195 DI 10.1021/om000720e PG 3 WC Chemistry, Inorganic & Nuclear; Chemistry, Organic SC Chemistry GA 367XD UT WOS:000090086200003 ER PT J AU Kaplinghat, M Knox, L Turner, MS AF Kaplinghat, M Knox, L Turner, MS TI Annihilating cold dark matter SO PHYSICAL REVIEW LETTERS LA English DT Article ID GALAXIES; HALOS AB Structure formation with cold dark matter (CDM) predicts halos with a central density cusp, which are observationally disfavored. If CDM particles have an annihilation cross section sigma upsilon similar to 10(-29)(m/ GeV) cm(2), then annihilations will soften the cusps. We discuss plausible scenarios for avoiding the early Universe annihilation catastrophe that could result from such a large cross section. The predicted scaling of core density with halo mass depends upon the velocity dependence of sigma upsilon, and s-wave annihilation leads to a core density nearly independent of halo mass, which seems consistent with observations. C1 Univ Chicago, Dept Astron & Astrophys, Chicago, IL 60637 USA. NASA, Fermi Natl Accelerator Lab, Fermilab Astrophys Ctr, Batavia, IL 60510 USA. Univ Chicago, Enrico Fermi Inst, Dept Phys, Chicago, IL 60637 USA. RP Kaplinghat, M (reprint author), Univ Chicago, Dept Astron & Astrophys, 5640 S Ellis Ave, Chicago, IL 60637 USA. NR 30 TC 114 Z9 114 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD OCT 16 PY 2000 VL 85 IS 16 BP 3335 EP 3338 DI 10.1103/PhysRevLett.85.3335 PG 4 WC Physics, Multidisciplinary SC Physics GA 363YU UT WOS:000089865900001 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 Atac, M Azfar, F Azzi-Bacchetta, P Bacchetta, N Bailey, MW Bailey, S de Barbaro, P Barbaro-Galtieri, A Barnes, VE Barnett, BA Barone, M Bauer, G Bedeschi, F Belforte, S Bellettini, G Bellinger, J Benjamin, D Bensinger, J Beretvas, A Berge, JP Berryhill, J Bevensee, B Bhatti, A Binkley, M Bisello, D 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 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 Ciobanu, CI Clark, AG Connolly, A Conway, J Cooper, J Cordelli, M Cranshaw, J Cronin-Hennessy, D Cropp, R Culbertson, R Dagenhart, D DeJongh, F Dell'Agnello, S Dell'Orso, M Demina, R Demortier, L Deninno, M Derwent, PF Devlin, T Dittmann, JR Donati, S Done, J Dorigo, T Eddy, N Einsweiler, K Elias, JE Engels, E Erdmann, W Errede, D Errede, S Fan, Q Feild, RG Ferretti, C Field, RD Fiori, I Flaugher, B Foster, GW Franklin, M Freeman, J Friedman, J Frisch, H Fukui, Y Galeotti, S Gallinaro, M Gao, T Garcia-Sciveres, M Garfinkel, AF Gatti, P Gay, C Geer, S Gerdes, DW Giannetti, P Giromini, P Glagolev, V Gold, M Goldstein, J Gordon, A Goshaw, AT Gotra, Y Goulianos, K Green, C Groer, L Grosso-Pilcher, C Guenther, M Cuillian, G da Costa, JG Guo, RS 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 Hinrichsen, B 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 Kirby, M Kirk, M Kim, BJ Kim, DH Kim, HS Kim, MJ Kim, SH Kim, YK 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, M Latino, G LeCompte, T Lee, AM Lee, K Leone, S Lewis, JD Lindgren, M Liss, TM Liu, JB Liu, YC 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 Miao, T Miller, R Miller, JS Minato, H Miscetti, S Mishina, M Mitselmakher, G Moggi, N Moore, E Moore, R Morita, Y Mukherjee, A Muller, T Munar, A Murat, P Murgia, S Musy, M Nachtman, J Nahn, S Nakada, H Nakaya, T Nakano, I Nelson, C Neuberger, D Newman-Holmes, C Ngan, CYP Nicolaidi, P 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 Pupadimitriou, V Pappas, SP Partos, D Patrick, J Pauletta, G Paulini, M Paus, C Pescara, L Phillips, TJ Piacentino, G Pitts, KT Plunkett, R 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 Riegler, W Ribon, A Rimondi, F Ristori, L Robertson, WJ Robinson, A Rodrigo, T Rolli, S Rosenson, L Roser, R Rossin, R Safonov, A Sakumoto, WK Saltzberg, D 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 Signorelli, G 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 Teng, PK Terashi, K Tether, S Theriot, D 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, CH Wang, MJ Watanabe, T Waters, D Watts, T Webb, R Wenzel, H Wester, WC Wicklund, AB Wicklund, E 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 Atac, M Azfar, F Azzi-Bacchetta, P Bacchetta, N Bailey, MW Bailey, S de Barbaro, P Barbaro-Galtieri, A Barnes, VE Barnett, BA Barone, M Bauer, G Bedeschi, F Belforte, S Bellettini, G Bellinger, J Benjamin, D Bensinger, J Beretvas, A Berge, JP Berryhill, J Bevensee, B Bhatti, A Binkley, M Bisello, D 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 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 Ciobanu, CI Clark, AG Connolly, A Conway, J Cooper, J Cordelli, M Cranshaw, J Cronin-Hennessy, D Cropp, R Culbertson, R Dagenhart, D DeJongh, F Dell'Agnello, S Dell'Orso, M Demina, R Demortier, L Deninno, M Derwent, PF Devlin, T Dittmann, JR Donati, S Done, J Dorigo, T Eddy, N Einsweiler, K Elias, JE Engels, E Erdmann, W Errede, D Errede, S Fan, Q Feild, RG Ferretti, C Field, RD Fiori, I Flaugher, B Foster, GW Franklin, M Freeman, J Friedman, J Frisch, H Fukui, Y Galeotti, S Gallinaro, M Gao, T Garcia-Sciveres, M Garfinkel, AF Gatti, P Gay, C Geer, S Gerdes, DW Giannetti, P Giromini, P Glagolev, V Gold, M Goldstein, J Gordon, A Goshaw, AT Gotra, Y Goulianos, K Green, C Groer, L Grosso-Pilcher, C Guenther, M Cuillian, G da Costa, JG Guo, RS 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 Hinrichsen, B 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 Kirby, M Kirk, M Kim, BJ Kim, DH Kim, HS Kim, MJ Kim, SH Kim, YK 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, M Latino, G LeCompte, T Lee, AM Lee, K Leone, S Lewis, JD Lindgren, M Liss, TM Liu, JB Liu, YC 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 Miao, T Miller, R Miller, JS Minato, H Miscetti, S Mishina, M Mitselmakher, G Moggi, N Moore, E Moore, R Morita, Y Mukherjee, A Muller, T Munar, A Murat, P Murgia, S Musy, M Nachtman, J Nahn, S Nakada, H Nakaya, T Nakano, I Nelson, C Neuberger, D Newman-Holmes, C Ngan, CYP Nicolaidi, P 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 Pupadimitriou, V Pappas, SP Partos, D Patrick, J Pauletta, G Paulini, M Paus, C Pescara, L Phillips, TJ Piacentino, G Pitts, KT Plunkett, R 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 Riegler, W Ribon, A Rimondi, F Ristori, L Robertson, WJ Robinson, A Rodrigo, T Rolli, S Rosenson, L Roser, R Rossin, R Safonov, A Sakumoto, WK Saltzberg, D 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 Signorelli, G 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 Teng, PK Terashi, K Tether, S Theriot, D 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, CH Wang, MJ Watanabe, T Waters, D Watts, T Webb, R Wenzel, H Wester, WC Wicklund, AB Wicklund, E 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 TI Direct measurement of the W boson width in p(p)over-bar collisions at root s=1.8 TeV SO PHYSICAL REVIEW LETTERS LA English DT Article ID PARTON DISTRIBUTIONS; MASS AB This Letter describes a direct measurement of the W boson total decay width, Gamma(W), using the Collider Detector at Fermilab. The measurement uses an integrated luminosity of 90 pb-L, collected during the 1994-1995 run of the Fermilab Tevatron pr collider. The width is determined by normalizing predicted signal and background distributions to 49 843 W --> ev candidates and 21 806 W --> mu nu candidates in the transverse-mass region M-T < 200 GeV and then fitting the predicted shape to the 438 electron events and 196 muon events in the high-M-T region, 100 < M-T < 200 GeV. The result is Gamma(W) = 2.04 +/- 0.11(stat) +/- 0.09(syst) GeV. 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 Los Angeles, Los Angeles, CA 90024 USA. Univ Cantabria, CSIC, Inst Fis Cantabria, E-39005 Santander, Spain. Univ Chicago, Enrico Fermi Inst, Chicago, IL 60637 USA. Joint Inst Nucl Res, RU-141980 Dubna, Russia. Duke Univ, Durham, NC 27708 USA. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Florida, Gainesville, FL 32611 USA. Ist Nazl Fis Nucl, Lab Nazl Frascati, I-00044 Frascati, Italy. Univ Geneva, CH-1211 Geneva 4, Switzerland. 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, Korean Hadron Collider Lab, 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, 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 Lancaster, Mark/C-1693-2008; Vucinic, Dejan/C-2406-2008; Nomerotski, Andrei/A-5169-2010; Azzi, Patrizia/H-5404-2012; Punzi, Giovanni/J-4947-2012; Chiarelli, Giorgio/E-8953-2012; Scodellaro, Luca/K-9091-2014; Paulini, Manfred/N-7794-2014; vilar, rocio/P-8480-2014; Prokoshin, Fedor/E-2795-2012; Introzzi, Gianluca/K-2497-2015 OI Azzi, Patrizia/0000-0002-3129-828X; Punzi, Giovanni/0000-0002-8346-9052; Chiarelli, Giorgio/0000-0001-9851-4816; Scodellaro, Luca/0000-0002-4974-8330; Paulini, Manfred/0000-0002-6714-5787; Prokoshin, Fedor/0000-0001-6389-5399; Introzzi, Gianluca/0000-0002-1314-2580 NR 20 TC 21 Z9 21 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 OCT 16 PY 2000 VL 85 IS 16 BP 3347 EP 3352 DI 10.1103/PhysRevLett.85.3347 PG 6 WC Physics, Multidisciplinary SC Physics GA 363YU UT WOS:000089865900004 ER PT J AU Petkov, V Billinge, SJL Shastri, SD Himmel, B AF Petkov, V Billinge, SJL Shastri, SD Himmel, B TI Polyhedral units and network connectivity in calcium aluminosilicate glasses from high-energy X-ray diffraction SO PHYSICAL REVIEW LETTERS LA English DT Article ID SCATTERING; PROGRAM; SILICA AB Structure factors for Cax/2AlxSi1-xO2 glasses (x = 0,0.25,0.5,0.67) extended to a wave vector of magnitude Q = 40 Angstrom(-1) have been obtained by high-energy x-ray diffraction. For the first time, it is possible to resolve the contributions of Si-O, Al-O, and Ca-O coordination polyhedra to the experimental atomic pair distribution functions. It has been found that the connectivity of Si/Al-O tetrahedral network decreases with increasing x due to the emerging of nonbridging oxygens located on Si-O tetrahedra. Calcium maintains a rather uniform coordination sphere for all values of x and so it plays a certain role in determining the glass structure. C1 Michigan State Univ, Dept Phys & Astron, E Lansing, MI 48823 USA. Michigan State Univ, Ctr Fundamental Mat Res, E Lansing, MI 48823 USA. Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. Univ Rostock, FB Elektrotech & Informat Tech, D-2500 Rostock 1, Germany. RP Petkov, V (reprint author), Michigan State Univ, Dept Phys & Astron, E Lansing, MI 48823 USA. NR 18 TC 99 Z9 101 U1 1 U2 18 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 OCT 16 PY 2000 VL 85 IS 16 BP 3436 EP 3439 DI 10.1103/PhysRevLett.85.3436 PG 4 WC Physics, Multidisciplinary SC Physics GA 363YU UT WOS:000089865900026 ER PT J AU Errandonea, D Boehler, R Ross, M AF Errandonea, D Boehler, R Ross, M TI Melting of the rare earth metals and f-electron delocalization SO PHYSICAL REVIEW LETTERS LA English DT Article ID HIGH-PRESSURE PHASE; SAMARIUM; PRASEODYMIUM; TRANSITIONS; DIAGRAM; IRON AB Melting curves for Pr, Nd, Sm, Gd, and Y were measured in a diamond-anvil-cell to nearly 100 GPa and 4000 K. f-electron volume collapses are observed as triple points for Pr (24 GPa and 1400 K) and Gd (65 GPa and 3100 K). These pressures coincide with the volume collapses observed at room temperature. For Nd and Sm, the f-electron volume collapse has not been observed at room temperature but appears at similar to 2000-2500 K as a broad minimum in the melting curve, similar to that of Ce, near 50 GPa (Nd) and 70 GPa (Sm). The melting curve of Y goes smoothly along the entire rare earth sequence. C1 Max Planck Inst Chem, D-55020 Mainz, Germany. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Errandonea, D (reprint author), Max Planck Inst Chem, Postfach 3060, D-55020 Mainz, Germany. RI Errandonea, Daniel/J-7695-2016 OI Errandonea, Daniel/0000-0003-0189-4221 NR 24 TC 46 Z9 46 U1 1 U2 12 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 OCT 16 PY 2000 VL 85 IS 16 BP 3444 EP 3447 DI 10.1103/PhysRevLett.85.3444 PG 4 WC Physics, Multidisciplinary SC Physics GA 363YU UT WOS:000089865900028 ER PT J AU Dunsiger, SR Gardner, JS Chakhalian, JA Cornelius, AL Jaime, M Kiefl, RF Movshovich, R MacFarlane, WA Miller, RI Sonier, JE Gaulin, BD AF Dunsiger, SR Gardner, JS Chakhalian, JA Cornelius, AL Jaime, M Kiefl, RF Movshovich, R MacFarlane, WA Miller, RI Sonier, JE Gaulin, BD TI Low temperature spin dynamics of the geometrically frustrated antiferromagnetic garnet Gd3Ga5O12 SO PHYSICAL REVIEW LETTERS LA English DT Article ID GADOLINIUM GALLIUM GARNET; LONG-RANGE ORDER; KAGOME ANTIFERROMAGNET; PYROCHLORE; GLASS; MUON; RELAXATION; Y2MO2O7; MAGNET; HEAT AB The low temperature spin dynamics of the geometrically frustrated antiferromagnet Gd3Ga5O12 (GGG) have been investigated using muon spin relaxation. No evidence for static order is seen down to a temperature of 25 mK or a few percent of the Curie-Weiss temperature. Instead there is a linear decrease in the Gd spin fluctuation rate below 1 K which extrapolates to a small but finite value of 2 GHz at zero temperature. In terms of the spin fluctuations the system appears essentially to remain dynamic at low temperatures (T > 0.02 K) and magnetic fields up to 1.8 T. C1 Univ British Columbia, Dept Phys & Astron, Vancouver, BC V6T 1Z1, Canada. McMaster Univ, Dept Phys & Astron, Hamilton, ON L8S 4M1, Canada. Univ Nevada, Dept Phys, Las Vegas, NV 89154 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. TRIUMF, Vancouver, BC V6T 2A3, Canada. RP Dunsiger, SR (reprint author), Univ British Columbia, Dept Phys & Astron, Vancouver, BC V6T 1Z1, Canada. RI Cornelius, Andrew/A-9837-2008; Piper, Walter/B-7908-2009; Gardner, Jason/A-1532-2013; Jaime, Marcelo/F-3791-2015; Chakhalian, Jak/F-2274-2015 OI Jaime, Marcelo/0000-0001-5360-5220; NR 33 TC 37 Z9 37 U1 1 U2 17 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 OCT 16 PY 2000 VL 85 IS 16 BP 3504 EP 3507 DI 10.1103/PhysRevLett.85.3504 PG 4 WC Physics, Multidisciplinary SC Physics GA 363YU UT WOS:000089865900043 ER PT J AU Viola, L Knill, E Lloyd, S AF Viola, L Knill, E Lloyd, S TI Dynamical generation of noiseless quantum subsystems SO PHYSICAL REVIEW LETTERS LA English DT Article ID DECOHERENCE; SYSTEMS; COMPUTATION; UNIVERSAL; CODES AB We combine dynamical decoupling and universal control methods for open quantum systems with coding procedures. By exploiting a general algebraic approach, we show how appropriate encodings of quantum states result in obtaining universal control over dynamically generated noise-protected subsystems with limited control resources. In particular, we provide a constructive scheme based on two-body Hamiltonians for performing universal quantum computation over large noiseless spaces which can be engineered in the presence of arbitrary linear quantum noise. C1 MIT, Dept Mech Engn, dArbeloff Lab Informat Syst & Technol, Cambridge, MA 02139 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Viola, L (reprint author), MIT, Dept Mech Engn, dArbeloff Lab Informat Syst & Technol, Cambridge, MA 02139 USA. NR 23 TC 115 Z9 116 U1 1 U2 6 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD OCT 16 PY 2000 VL 85 IS 16 BP 3520 EP 3523 DI 10.1103/PhysRevLett.85.3520 PG 4 WC Physics, Multidisciplinary SC Physics GA 363YU UT WOS:000089865900047 ER PT J AU Griffiths, SK Nilson, RH AF Griffiths, SK Nilson, RH TI Electroosmotic fluid motion and late-time solute transport for large zeta potentials SO ANALYTICAL CHEMISTRY LA English DT Article ID CAPILLARY-ZONE-ELECTROPHORESIS; OPEN-CHANNEL ELECTROCHROMATOGRAPHY; LIQUID-CHROMATOGRAPHY; FLOW; MICROCHIP; DISPERSION; SEPARATIONS; SYSTEMS; GLASS; CHIPS AB Analytical and numerical methods are employed to determine the electric potential, fluid velocity, and late-time solute distribution for electroosmotic now in a tube and channel at zeta potentials that are not necessarily small. The electric potential and fluid velocity are in general obtained by numerical means. In addition, new analytical solutions are presented for the velocity in a tube and channel in the extremes of large and small Debye layer thickness. The electroosmotic fluid velocity is used to analyze late-time transport of a neutral nonreacting solute. Zero- and first-order solutions describing axial variation of the solute concentration are determined analytically. The resulting expressions contain eigenvalues representing the dispersion and skewness of the axial concentration profiles. These eigenvalues and the functions describing transverse variation of the concentration field are determined numerically using a shooting technique. Results are presented for both tube and channel geometries over a wide range of the normalized Debye layer thickness and zeta potential. Simple analytical approximations to the eigen-values are also provided for the limiting cases of large and small values of the Debye layer thickness. C1 Sandia Natl Labs, Livermore, CA 94551 USA. RP Griffiths, SK (reprint author), Sandia Natl Labs, POB 969, Livermore, CA 94551 USA. NR 36 TC 51 Z9 51 U1 1 U2 8 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 OCT 15 PY 2000 VL 72 IS 20 BP 4767 EP 4777 DI 10.1021/ac000539f PG 11 WC Chemistry, Analytical SC Chemistry GA 364ZW UT WOS:000089924800001 ER PT J AU Patel, R Zhou, RN Zinszer, K Josse, F Cernosek, R AF Patel, R Zhou, RN Zinszer, K Josse, F Cernosek, R TI Real-time detection of organic compounds in liquid environments using polymer-coated thickness shear mode quartz resonators SO ANALYTICAL CHEMISTRY LA English DT Article ID ACOUSTIC-WAVE MICROSENSORS; ONLINE DETECTION; CHEMICAL SENSORS; CRYSTAL MICROBALANCE; QCR SENSORS; WATER AB The selection of sensitive coatings is a critical task in the design and implementation of chemical sensors using coated thickness shear mode quartz crystal resonators (QCRs) for detection in liquid environments, This design or selection is performed through a study of the sorption process in terms of the partition coefficients of the analytes in the coatings, The partition coefficient, which is controlled by the chemical and physical properties of the coating materials, determines the inherent selectivity and sensitivity toward analyte molecules. The selection of the coatings is logically determined by the interactions between coating and target analyte molecules, but can also be made through a systematic variation of the coating's properties. The determination of the partition coefficients is only accurate if all contributions to the total measured frequency shifts, Delta f(s), of the coated QCR can be established. While mass loading is often assumed to be the dominant factor used in determining partition coefficients, viscoelastic effects may also contribute to Delta f(s). Both the effect of viscoelastic properties and the effect of mass loading on the sensor responses are investigated by using a network analyzer and oscillator circuit and by characterizing the total mechanical impedance of the loaded sensor. Different types of coatings including rubbery and glassy polymers are investigated, and the targeted analytes include classes of polar compounds (methanol), nonpolar compounds (toluene, xylenes), and chlorinated hydrocarbons (trichloroethylene, tetrachloroethylene, etc). It is seen that changes in viscoelastic properties due to analyte sorption may be significant enough to place the sensor in the nongravimetric regime. However, for most applications involving the detection of relatively low concentrations of organic compounds and the use of acoustically thin films, changes in the complex shear modulus of the coatings contribute less than 546 of the total shift in the series resonant frequency, depending on the coating. In that case, the measured Delta f(s) and, hence, the calculated sensitivity/partition coefficients can still be used for an approximate classification and selection of the coatings for operation in a complex solution of water/analyte molecules. C1 Univ Wisconsin, Dept Elect & Comp Engn, Microsensor Res Lab, Milwaukee, WI 53201 USA. Sandia Natl Labs, Microsensor Res & Dev Dept, Albuquerque, NM 87185 USA. RP Josse, F (reprint author), Univ Wisconsin, Dept Elect & Comp Engn, Microsensor Res Lab, POB 1881, Milwaukee, WI 53201 USA. NR 39 TC 49 Z9 49 U1 0 U2 6 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0003-2700 J9 ANAL CHEM JI Anal. Chem. PD OCT 15 PY 2000 VL 72 IS 20 BP 4888 EP 4898 DI 10.1021/ac0003955 PG 11 WC Chemistry, Analytical SC Chemistry GA 364ZW UT WOS:000089924800017 ER PT J AU Woltman, SJ Even, WR Sahlin, E Weber, SG AF Woltman, SJ Even, WR Sahlin, E Weber, SG TI Chromatographic detection of nitroaromatic and nitramine compounds by electrochemical reduction combined with photoluminescence following electron transfer SO ANALYTICAL CHEMISTRY LA English DT Article ID DISPLACEMENT FLOW IMMUNOSENSOR; LIQUID-CHROMATOGRAPHY; POLYPYRIDINE COMPLEXES; AMPEROMETRIC DETECTION; EXPLOSIVE COMPOUNDS; DUAL-ELECTRODE; PHOTOPHYSICS; TRIS(2,2'-BIPYRIDYL)RUTHENIUM(III); PHOTOCHEMISTRY; LUMINESCENCE AB The oxidizing agent tris(bipyridyl)ruthenium(II), or Ru(bpy)(3)(3+), is used as a postcolumn reagent for the detection of nitroaromatic and nitramine explosive compounds. After separation, the explosives are reduced electrochemically to oxidizable products such as hydroxlamines and nitrosamines, and these products react readily with Ru(bpy)(3)(3+) and RU(bpy)(3)(2+). The photolumininescence from the latter is used far detection. A porous carbon electrode was used for on-line analyte reduction following chromatography. Another porous carbon electrode was used to generate the nonluminescent RU(bpy)(3)(3+) from Ru(bpy)(3)(3+) on-line at high efficiency. The two streams were combined, and the Ru(bpy)(3)(2+) produced by oxidation of the reduced analytes was detected by laser illumination and light detection, Reductive hydrodynamic voltammograms of nitrobenzene, 2,4,6-trinitotoluene, and hexahydro-1,3,5-trinitro-1,3,5-triazine indicated that a potential of -1500 mV vs Ag/AgCl was sufficient to achieve a maximum signal from the reduced analytes. HPLC with a water/acetonitrile gradient on a C-18 reversed-phase column was then used to determine these three compounds plus the four additional examples, 1,3,5,7-tetrazocine, 2,4-dinitrotoluene; 2,6-dinitrotoluene, and 4-nitrotoluene, For both hydrodynamic voltammetry and HPLC detection, the photoluminescence following electron-transfer signal was calibrated using the one-electron standards ferrocene and ferrocenecarboxylic acid. Detection limits were in the low-nanomolar range for 20-mu L injections of nonpreconcentrated nitro compounds. C1 Univ Pittsburgh, Chevron Sci Ctr, Pittsburgh, PA 15260 USA. Sandia Natl Labs, Livermore, CA 94550 USA. RP Weber, SG (reprint author), Univ Pittsburgh, Chevron Sci Ctr, Pittsburgh, PA 15260 USA. OI Weber, Stephen/0000-0002-7970-2632 FU NIGMS NIH HHS [GM-44842] NR 22 TC 20 Z9 21 U1 1 U2 8 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 OCT 15 PY 2000 VL 72 IS 20 BP 4928 EP 4933 DI 10.1021/ac000170u PG 6 WC Chemistry, Analytical SC Chemistry GA 364ZW UT WOS:000089924800023 PM 11055711 ER PT J AU Kim, T Udseth, HR Smith, RD AF Kim, T Udseth, HR Smith, RD TI Improved ion transmission from atmospheric pressure to high vacuum using a multicapillary inlet and electrodynamic ion funnel interface SO ANALYTICAL CHEMISTRY LA English DT Article ID IONIZATION MASS-SPECTROMETRY AB A heated multicapillary inlet and ion funnel interface was developed to couple an electrospray ionization (ESI) source to a high-vacuum stage for obtaining improved sensitivity in mass spectrometric applications. The inlet was constructed from an array of seven thin-wall stainless steel tubes soldered into a central hole of a cylindrical heating block. An electrodynamic ion funnel was used in the interface region to more effectively capture, focus, and transmit ions from the multicapillary inlet. The interface of seven capillary inlets with the ion funnel showed more than 7 times higher transmission efficiency compared to that of a single capillary inlet with the ion funnel and a 23-fold greater transmission efficiency than could be obtained using the standard orifice-skimmer interface of a triple-quadrupole MS. The multiple-capillary inlet and ion funnel interface showed an overall 10% ion transmission efficiency and approximately 3-4% overall detection efficiency of ions from solution based (i.e., prior to electrospray). The improved performance was achieved under conditions where ESI operation is robust and results in a significant increase in dynamic range. C1 Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Smith, RD (reprint author), Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RI Smith, Richard/J-3664-2012 OI Smith, Richard/0000-0002-2381-2349 NR 10 TC 42 Z9 43 U1 3 U2 30 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 OCT 15 PY 2000 VL 72 IS 20 BP 5014 EP 5019 DI 10.1021/ac0003549 PG 6 WC Chemistry, Analytical SC Chemistry GA 364ZW UT WOS:000089924800035 ER PT J AU Rodgers, RP Lazar, AC Reilly, PTA Whitten, WB Ramsey, JM AF Rodgers, RP Lazar, AC Reilly, PTA Whitten, WB Ramsey, JM TI Direct determination of soil surface bound polycyclic aromatic hydrocarbons in petroleum-contaminated soils by real time aerosol mass spectrometry SO ANALYTICAL CHEMISTRY LA English DT Article ID FINE ORGANIC AEROSOL; BIOLOGICAL CHARACTERIZATION; CHEMICAL-ANALYSIS; ROAD DUST; PARTICLES; EMISSIONS; IONIZATION; FUELS; IDENTIFICATION; MICROPARTICLES AB Soil surface-bound polycyclic aromatic hydrocarbons (PAHs) were identified by use of Real-Tune Aerosol Mass Spectrometry (RTAMS) in two NIST standard research material (SRM) soils (Montana SRM 2710 and Peruvian SRM 4355) each contaminated separately with three common petroleum hydrocarbons (diesel fuel, gasoline, and kerosene). The described contaminated soil analysis required no sample preparation. Direct laser desorption/ionization mass spectrometric analysis of individual soil particles contaminated with each of the petroleum hydro-carbons at three different contamination levels (0.8, 8, and 80 ppth (wt/wt)) yielded detectable PAH cation distributions that ranged from m/z 128 to 234, depending on the fuel contaminant. The same analysis performed on uncontaminated SRM soils revealed very little (Peruvian) to no (Montana) detectable PAH species. Size analysis showed that most of the individual soil particles analyzed were between 1 and 5 pm in diameter. Tandem mass spectrometry (MS/MS) experiments identified alkyl-substituted two- and three-ringed PAHs in all three petroleum hydrocarbon contaminated soils. However, due to similarities in fragmentation patterns, MS/MS analysis of higher MW species (m/z > 200) was unable to distinguish between the possibility of highly alkyl-substituted three-ringed PAHs and hydrogenated four-ringed PAHs, The described technique offers the direct, rapid determination and characterization of surface-bound PAHs in petroleum-contaminated soils at part-per-million levels without prior extraction, separation, or other sample preparation methods. C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Reilly, PTA (reprint author), Oak Ridge Natl Lab, Div Chem & Analyt Sci, POB 2008,MS-6142, Oak Ridge, TN 37831 USA. NR 55 TC 15 Z9 16 U1 0 U2 14 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0003-2700 J9 ANAL CHEM JI Anal. Chem. PD OCT 15 PY 2000 VL 72 IS 20 BP 5040 EP 5046 DI 10.1021/ac000513o PG 7 WC Chemistry, Analytical SC Chemistry GA 364ZW UT WOS:000089924800038 ER PT J AU Tsai, MS Hornby, AE Lakins, J Lupu, R AF Tsai, MS Hornby, AE Lakins, J Lupu, R TI Expression and function of CYR61, an angiogenic factor, in breast cancer cell lines and tumor biopsies SO CANCER RESEARCH LA English DT Article ID IMMEDIATE-EARLY GENE; DRUG-RESISTANCE; CHROMOSOME 1P; GROWTH; HEREGULIN; PRODUCT; PROGRESSION; DELETION; RECEPTOR AB We have previously shown that expression of heregulin (HRG) is closely correlated with breast cancer progression. We have subsequently isolated Cyr61, a ligand fur the alpha (v)beta (3) integrin that is differentially expressed in HRG-positive cells, and have? shown that it is expressed in all of the invasive and metastatic breast cancer cell lines tested. Preliminary evaluation of Cyr61 expression in breast tumor biopsies revealed expression of Cyr61 in about 30% of invasive breast carcinomas. Significantly, we demonstrated that Cyr61 is a downstream effector of HRG action, because a Cyr61-neutralizing antibody abolished the ability of HRG-expressing cells to migrate in vitro. Furthermore, we have shown that HRG-expressing cells denote higher levels of alpha (v)beta (3) expression, and we have established that Cyr61 action is mediated, at least in part, through its receptor alpha (v)beta (3), because a functional blocking antibody of the alpha (v)beta (3) blocked the Matrigel outgrowth of HRG-expressing cells. These results strongly suggest that Cyr61 is necessary for HRG-mediated chemomigration and that Cyr61 plays a functional role in breast cancer progression, possibly through its interactions with the alpha (v)beta (3) receptor. C1 Univ Calif Berkeley, Ernest Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Lupu, R (reprint author), Univ Calif Berkeley, Ernest Lawrence Berkeley Natl Lab, 1 Cyclotron Rd, Berkeley, CA 94720 USA. FU NIDDK NIH HHS [DK49049] NR 21 TC 101 Z9 104 U1 0 U2 3 PU AMER ASSOC CANCER RESEARCH PI BIRMINGHAM PA PO BOX 11806, BIRMINGHAM, AL 35202 USA SN 0008-5472 J9 CANCER RES JI Cancer Res. PD OCT 15 PY 2000 VL 60 IS 20 BP 5603 EP 5607 PG 5 WC Oncology SC Oncology GA 367HC UT WOS:000090054800003 PM 11059746 ER PT J AU Rosenberg, ND Fisher, AT Stein, JS AF Rosenberg, ND Fisher, AT Stein, JS TI Large-scale lateral heat and fluid transport in the seafloor: revisiting the well-mixed aquifer model SO EARTH AND PLANETARY SCIENCE LETTERS LA English DT Article DE ocean floors; hydrothermal conditions; heat flow; fluid dynamics ID OCEANIC-CRUST; FLOW; LITHOSPHERE; SEDIMENT; RIDGE; CONSTRAINTS; SEAWATER; FLUXES; FLANK; AGE AB Large-scale, lateral fluid flow through oceanic crust provides an explanation for regionally low heat flow in several seafloor settings. A well-mixed aquifer (WMA) model provides a quantitative and conceptual tool for explaining anomalously low heat flow based on an analytical representation of fluid and heat flow, assuming lateral fluid flow in basement in a layer directly below the ocean sediments. We present an extended well-mixed aquifer (EWMA) model that allows fluid flow at greater depths within the oceanic crust. Flow through a deeper permeable layer extracts more heat than equivalent flow through a shallower layer of equal thickness, and may help to reconcile global heat flow and seafloor permeability data, since deeper flow does not require velocities as great as shallow flow to account for the same heat loss, and thus permeability can be lower. Numerical simulations that test the hydrodynamic validity of the WMA. and EWMA equations indicate that the analytical models provide reasonable approximations of large-scale, lateral heat transport when lateral fluid flow in the crust is confined to thin layers. The efficiency of lateral heat transport is reduced as vertical mixing within the lateral flow layer increases. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Calif Lawrence Livermore Natl Lab, Earth & Environm Sci Directorate, Livermore, CA 94551 USA. Univ Calif Santa Cruz, Dept Earth Sci, Santa Cruz, CA 95064 USA. Univ Calif Santa Cruz, Inst Tecton, Santa Cruz, CA 95064 USA. RP Rosenberg, ND (reprint author), Univ Calif Lawrence Livermore Natl Lab, Earth & Environm Sci Directorate, Livermore, CA 94551 USA. RI Fisher, Andrew/A-1113-2016 NR 24 TC 13 Z9 15 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0012-821X J9 EARTH PLANET SC LETT JI Earth Planet. Sci. Lett. PD OCT 15 PY 2000 VL 182 IS 1 BP 93 EP 101 DI 10.1016/S0012-821X(00)00235-1 PG 9 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 360YN UT WOS:000089695100007 ER PT J AU Collon, P Kutschera, W Loosli, HH Lehmann, BE Purtschert, R Love, A Sampson, L Anthony, D Cole, D Davids, B Morrissey, DJ Sherrill, BM Steiner, M Pardo, RC Paul, M AF Collon, P Kutschera, W Loosli, HH Lehmann, BE Purtschert, R Love, A Sampson, L Anthony, D Cole, D Davids, B Morrissey, DJ Sherrill, BM Steiner, M Pardo, RC Paul, M TI Kr-81 in the Great Artesian Basin, Australia: a new method for dating very old groundwater SO EARTH AND PLANETARY SCIENCE LETTERS LA English DT Article DE geochemistry; hydrology; ground water; noble gases; cosmogenic elements; isotope ratios; accelerator mass spectroscopy ID CL-36; ION; SPECTROSCOPY; KRYPTON; ATOMS; AMS AB The measurement of cosmogenic Kr-81 (t(1/2) = (2.29 +/- 0.11) x 10(5) yr) has been proposed for many years as a reliable tool for groundwater dating in the range from 10(5) to 10(6) yr. In this paper, we report on the first use of Kr-81 to determine the age of groundwater from four wells in the Great Artesian Basin in Australia. As the concentration of Kr-81 in old groundwater is only a few hundred atoms per liter, krypton was extracted from large (16 000 1) groundwater samples and was analyzed for the isotopic abundance of Kr-81 by accelerator mass spectrometry (AMS) with a cyclotron. Kr-81/Kr isotope ratios of (1.54 +/- 0.22) x 10(-13), (1.78 +/- 0.26) x 10(-13), (2.19 +/- 0.28) x 10(-13) and (2.63 +/- 0.32) x 10(-13) respectively, were measured for these samples. It is reasonable to assume that krypton dissolved in surface water in contact with the atmosphere has the known atmospheric Kr-81/Kr ratio of (5.20 +/- 0.40) x 10(-13). The observed reduction of isotope ratios in the groundwater samples can then be interpreted as being due to radioactive decay since recharge. This results in respective groundwater ages of: (4.02 +/- 0.51) x 10(5) yr, (3.54 +/- 0.50) x 10(5) yr, (2.87 +/- 0.38) x 10(5) yr and (2.25 +/- 0.42) x 10(5) yr. The main emphasis of this paper lies on the description of the analytic procedure to extract a reliable Kr-81 signal from large groundwater samples. Although the uncertainties are still relatively large (primarily due to counting statistics caused by the low cyclotron AMS efficiency), the new technique enabled for the first time a definite determination of residence times for old groundwater with Kr-81. It thus confirms the hope that this radionuclide may become a very valuable tool for groundwater dating. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Vienna, Inst Isotopenforsch & Kernphys, A-1090 Vienna, Austria. Univ Bern, Inst Phys, CH-3012 Bern, Switzerland. Primary Ind & Resources S Australia, Adelaide, SA, Australia. Michigan State Univ, Natl Superconducting Cyclotron Lab, E Lansing, MI 48824 USA. Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. Hebrew Univ Jerusalem, Racah Inst Phys, IL-91904 Jerusalem, Israel. RP Collon, P (reprint author), Univ Vienna, Inst Isotopenforsch & Kernphys, Waehringer Guertel 18, A-1090 Vienna, Austria. RI Sherrill, Bradley/B-4098-2009; Sherrill, Bradley/B-3378-2011; Purtschert, Roland/N-7108-2016 OI Purtschert, Roland/0000-0002-4734-7664 NR 30 TC 51 Z9 57 U1 2 U2 16 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0012-821X J9 EARTH PLANET SC LETT JI Earth Planet. Sci. Lett. PD OCT 15 PY 2000 VL 182 IS 1 BP 103 EP 113 DI 10.1016/S0012-821X(00)00234-X PG 11 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 360YN UT WOS:000089695100008 ER PT J AU Gardea-Torresdey, JL Tiemann, KJ Gamez, G Dokken, K Cano-Aguilera, I Furenlid, LR Renner, MW AF Gardea-Torresdey, JL Tiemann, KJ Gamez, G Dokken, K Cano-Aguilera, I Furenlid, LR Renner, MW TI Reduction and accumulation of gold(III) by Medicago sativa alfalfa biomass: X-ray absorption spectroscopy, pH, and temperature dependence SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Article ID GOLD NANOPARTICLES; ALGAL BIOMASS; COPPER IONS; ADSORPTION; BINDING; EXAFS; BIOSORPTION; COMPLEXES; CR(III); LIGANDS AB We report herein the use of Medicago sativa alfalfa shoot biomass for the removal of gold from aqueous solutions. The accumulation process involves the reduction of Au(lll) to colloidal Au(0) and is shown to increase at elevated temperatures and at lower pH. X-ray absorption spectroscopy (XAS) was used to determine that gold(lll) was reduced to form gold(0) colloids, which varied in size depending on the pH of the initial solution. The gold cluster radius was 6.2 +/- 1 Angstrom at pH 5 and 9.0 +/- 1 Angstrom at pH 2. Our findings indicate that essentially another layer of gold atoms was deposited onto the colloid surface at pH 2. Possible mechanisms of bioreduction and accumulation are discussed. C1 Univ Texas, Dept Chem, El Paso, TX 79968 USA. Univ Guanajuato, Fac Quim, Guanajuato, Mexico. Univ Arizona, Ctr Opt Sci, Tucson, AZ 85719 USA. Brookhaven Natl Lab, Dept Appl Sci, Upton, NY 11973 USA. RP Gardea-Torresdey, JL (reprint author), Univ Texas, Dept Chem, El Paso, TX 79968 USA. RI Gamez, Gerardo/C-9733-2011 OI Gamez, Gerardo/0000-0002-8827-6647 FU NIBIB NIH HHS [P41 EB002035]; NIGMS NIH HHS [S06 GM008012] NR 52 TC 57 Z9 57 U1 1 U2 14 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 OCT 15 PY 2000 VL 34 IS 20 BP 4392 EP 4396 DI 10.1021/es991325m PG 5 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 365UZ UT WOS:000089970000021 PM 26635419 ER PT J AU Urbansky, ET Magnuson, ML Kelty, CA Gu, B Brown, GM AF Urbansky, ET Magnuson, ML Kelty, CA Gu, B Brown, GM TI Comment on "Perchlorate identification in fertilizers" and the subsequent addition/correction SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Letter C1 US EPA, Natl Risk Management Res lab, Water Supply & Water Resources Div, Cincinnati, OH 45268 USA. Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Urbansky, ET (reprint author), US EPA, Natl Risk Management Res lab, Water Supply & Water Resources Div, Cincinnati, OH 45268 USA. RI Gu, Baohua/B-9511-2012 OI Gu, Baohua/0000-0002-7299-2956 NR 9 TC 33 Z9 33 U1 0 U2 8 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 OCT 15 PY 2000 VL 34 IS 20 BP 4452 EP 4453 DI 10.1021/es0011515 PG 2 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 365UZ UT WOS:000089970000031 ER PT J AU Lyons, LR Zesta, E Samson, JC Reeves, GD AF Lyons, LR Zesta, E Samson, JC Reeves, GD TI Auroral disturbances during the January 10, 1997 magnetic storm SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID SUDDEN IMPULSES; INTENSIFICATIONS; MAGNETOTAIL; ASSOCIATION; BOUNDARY; MIDNIGHT; CANOPUS; FLOWS AB It is well known that intense and frequent auroral-zone disturbances, often attributed to substorms, occur during magnetic storms. We examine observations during the January 10, 1997 main phase and find that observed auroral-zone activity was dominated by a combination of global auroral and current enhancements, which are a direct response to solar wind dynamic pressure enhancements, and poleward boundary intensifications, which are localized in longitude and have an auroral signature that moves equatorward from the magnetic separatrix. Poleward and azimuthally expanding regions of auroral activity which accompany substorms are found to contribute significantly less to the observed activity. This suggests that poleward boundary intensifications and dynamic pressure responses may be an important cause of disturbances during periods of enhanced convection such as magnetic storms and convection bays. C1 Univ Calif Los Angeles, Dept Atmospher Sci, Los Angeles, CA 90095 USA. Univ Alberta, Dept Phys, Edmonton, AB T6G 2E9, Canada. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Lyons, LR (reprint author), Univ Calif Los Angeles, Dept Atmospher Sci, Los Angeles, CA 90095 USA. RI Reeves, Geoffrey/E-8101-2011 OI Reeves, Geoffrey/0000-0002-7985-8098 NR 18 TC 46 Z9 46 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD OCT 15 PY 2000 VL 27 IS 20 BP 3237 EP 3240 DI 10.1029/1999GL000014 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 365RR UT WOS:000089964700002 ER PT J AU Kasaba, Y Terasawa, T Tsubouchi, K Mukai, T Saito, Y Matsumoto, H Kojima, H Steinberg, J McComas, D Skoug, R Matsui, H Hoshino, M AF Kasaba, Y Terasawa, T Tsubouchi, K Mukai, T Saito, Y Matsumoto, H Kojima, H Steinberg, J McComas, D Skoug, R Matsui, H Hoshino, M TI Magnetosheath electrons in anomalously low density solar wind observed by Geotail SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article AB We present an overview of the magnetosheath electron observations above 60 eV in the anomalously low density solar wind on 11 May 1999 observed by Geotail. We observed anisotropic 'strahl' component not only in the solar wind but also in the magnetosheath. Strahl, is observed during the interval of 6-21h UT and most enhanced in the interval surrounding the solar wind density minimum in 18-19h UT. Its temperature seems positively correlated to its flux. We also evaluate the density and temperature of low energy isotropic component. The variation of density is associated with proton density. Its temperature is continuous, and suddenly decreased after the density minimum in similar to 18-19h UT. We also compared our downstream data with upstream one observed by the ACE spacecraft. We conclude that the electron acceleration and heating at the bow shock is executed in the ordinal mechanisms even in the low density solar wind. C1 Inst Space & Astronaut Sci, Sagamihara, Kanagawa 2298510, Japan. Univ Tokyo, Dept Earth & Planetary Sci, Tokyo 1130033, Japan. Kyoto Univ, Radio Sci Ctr Space & Atmosphere, Uji, Kyoto 6110011, Japan. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Tokyo Inst Technol, Tokyo 1528511, Japan. RP Kasaba, Y (reprint author), Inst Space & Astronaut Sci, Sagamihara, Kanagawa 2298510, Japan. RI Tsubouchi, Ken/B-9343-2015 OI Tsubouchi, Ken/0000-0003-1963-1112 NR 8 TC 5 Z9 6 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD OCT 15 PY 2000 VL 27 IS 20 BP 3253 EP 3256 DI 10.1029/2000GL000086 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 365RR UT WOS:000089964700006 ER PT J AU Phillips, WS Hartse, HE Taylor, SR Randall, GE AF Phillips, WS Hartse, HE Taylor, SR Randall, GE TI 1 Hz Lg Q tomography in Central Asia SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID CODA-Q; LATERAL VARIATIONS; PROPAGATION; DISCRIMINATION; ATTENUATION; EARTHQUAKES; CHINA; EXCITATION; EXPLOSIONS; PHASE AB We have applied tomographic techniques to a data set of over 1700, regional distance, L-g amplitudes from 12 stations for paths inside a 30 degrees by 40 degrees region of Central Asia. Our purpose is to create high resolution path correction maps for use in regional distance source discrimination and magnitude determination, as well as to study L-g propagation characteristics in one of the most heterogeneous portions of the earth. For 1.0 Hz data, tomography reduced variance 33%, relative to a best fit, uniform Q model. L-g Q varied with geologic region, with low values in Tibet, the Tien Shan and the Pamir range (Q = 200 to 400), intermediate values in basins such as the Tarim (Q = 500) and high values for platforms and older crust (Q > 800). The relatively efficient propagation across the Tarim differs from the poor propagation that is generally observed across sedimentary basins. C1 Univ Calif Los Alamos Natl Lab, Seism Res Ctr, Los Alamos, NM 87545 USA. RP Phillips, WS (reprint author), Univ Calif Los Alamos Natl Lab, Seism Res Ctr, POB 1663, Los Alamos, NM 87545 USA. NR 24 TC 22 Z9 22 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD OCT 15 PY 2000 VL 27 IS 20 BP 3425 EP 3428 DI 10.1029/2000GL011482 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 365RR UT WOS:000089964700049 ER PT J AU Zaragoza, IP Martinez-Magadan, JM Santamaria, R Dixon, D Castro, M AF Zaragoza, IP Martinez-Magadan, JM Santamaria, R Dixon, D Castro, M TI DFT study of the interaction of the HZSM-5 zeolite with the benzene molecule SO INTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY LA English DT Article; Proceedings Paper CT 3rd Congress of the International Society for Theoretical Chemical Physics (ISTCP) CY NOV 08-13, 1999 CL UNIV NACL AUTONOMA MEXICO, MEXICO CITY, MEXICO SP Univ Nacl Autonoma Mexico, Fac Quim, Univ Nacl Autonoma Mexico, Inst Invest & Mat, Univ Nacl Autonoma Mexico, Inst Fis, Univ Nacl Autonoma Mexico, Coordinac Invest Cientif, Consejo Nacl Ciencia & Technol, Inst Mexicano Petroleo, Silicon Graph, SA CV HO UNIV NACL AUTONOMA MEXICO DE benzene; HZSM-5 zeolite; Bronsted acidity; density functional theory ID DYNAMIC BEHAVIORS; ZSM-5 ZEOLITE; SUBSTITUTION; SIMULATION; PREDICTION; LOCATION; PORES AB We have performed density functional theory (DFT) calculations to describe the interaction of an active site of the HZSM-5 zeolite with a benzene molecule. We used a ring of ten SiO4 tetrahedral (10T) units to represent the structure of the HZSM-5 zeolite. The calculations were of the all-electron type, the exchange-correlation contributions were taken into account by means of the BLYP density functional, and orbital basis;sets of double numerical polarization quality were employed for all atoms. Starting from the silicalite 10T ring, with silicon atoms at each site, we found the most energetically favored site for the substitution of an aluminum atom by a silicon atom to produce an HZSM-5 ring model, with a Si/Al ratio of 9. In order to simulate the adsorbed state of benzene onto the zeolite, the geometry of the aromatic molecule was fully optimized in its interaction with the zeolite model, while keeping the ring frozen. The electronic structure of the benzene-HZSM-5 complex was then analyzed and discussed. Our results account for a significant interaction between the acid proton from the HZSM-5 cavity with benzene, shown by changes of the pi-bond cloud of benzene, which would lead to an active carbocationic moiety. (C) 2000 John Wiley & Sans, Inc. C1 Inst Mexicano Petr, Programa Simulac Mol, Mexico City 07730, DF, Mexico. Pacific NW Natl Lab, WR Wiley EMSL, Richland, WA 99352 USA. Natl Autonomous Univ Mexico, Fac Quim, Dept Fis & Quim Teor, Mexico City 04510, DF, Mexico. RP Zaragoza, IP (reprint author), Inst Mexicano Petr, Programa Simulac Mol, AP 15-805, Mexico City 07730, DF, Mexico. RI Martinez-Magadan, Jose-Manuel/M-1973-2015 OI Martinez-Magadan, Jose-Manuel/0000-0003-1152-6924 NR 18 TC 11 Z9 11 U1 0 U2 4 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 USA SN 0020-7608 J9 INT J QUANTUM CHEM JI Int. J. Quantum Chem. PD OCT 15 PY 2000 VL 80 IS 2 BP 125 EP 132 DI 10.1002/1097-461X(2000)80:2<125::AID-QUA8>3.3.CO;2-0 PG 8 WC Chemistry, Physical; Mathematics, Interdisciplinary Applications; Physics, Atomic, Molecular & Chemical SC Chemistry; Mathematics; Physics GA 356TZ UT WOS:000089460100007 ER PT J AU Baur, K Kerner, J Brennan, S Singh, A Pianetta, P AF Baur, K Kerner, J Brennan, S Singh, A Pianetta, P TI Aluminum impurities in silicon: Investigation of x-ray Raman scattering in total reflection x-ray fluorescence spectroscopy SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID SYNCHROTRON-RADIATION AB Total reflection x-ray fluorescence using synchrotron radiation from the Stanford Synchrotron Radiation Laboratory has been used to study Al impurities on Si wafer surfaces. For primary excitation energies below the Si K absorption edge an inelastic resonance scattering due to resonant x-ray Raman scattering is observed. This scattering dominates the background behavior of the Al K fluorescence line, and consequently limits the achievable sensitivity for detection of Al surface contaminants. The energy and angle dependence of the resonant x-ray Raman scattering has been investigated to determine the experimental conditions for which the highest sensitivity for Al can be achieved. We find that for a precise determination of the achievable sensitivity, the specific shape of the continuous Raman background has to be taken into account. Our calculations demonstrate a minimum detection limit for Al of 6x10(9) atoms/cm(2) for a 10 000 s count time. (C) 2000 American Institute of Physics. [S0021-8979(00)04721-6]. C1 Stanford Univ, Stanford Synchrotron Radiat Lab, Stanford, CA 94309 USA. ARACOR, Sunnyvale, CA 94086 USA. RP Baur, K (reprint author), Stanford Univ, Stanford Synchrotron Radiat Lab, Stanford, CA 94309 USA. NR 22 TC 25 Z9 25 U1 0 U2 5 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 OCT 15 PY 2000 VL 88 IS 8 BP 4642 EP 4647 DI 10.1063/1.1312848 PG 6 WC Physics, Applied SC Physics GA 358HP UT WOS:000089552800028 ER PT J AU Myers, SM Wright, AF Petersen, GA Seager, CH Wampler, WR Crawford, MH Han, J AF Myers, SM Wright, AF Petersen, GA Seager, CH Wampler, WR Crawford, MH Han, J TI Equilibrium state of hydrogen in gallium nitride: Theory and experiment SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID CHEMICAL-VAPOR-DEPOSITION; ELECTRON BEAM IRRADIATION; EFFECTIVE-MASS; III NITRIDES; GAN; MG; ACTIVATION; ENERGY; ACCEPTORS; PRESSURES AB Formation energies and vibration frequencies for H in wurtzite GaN were calculated from density-functional theory and used to predict equilibrium state occupancies and solid solubilities at elevated temperatures for p-type, intrinsic, and n-type material. The solubility of deuterium (D) was measured in p-type, Mg-doped GaN at 600, 700, and 800 degrees C as a function of D-2 pressure and compared with theory. Agreement was obtained by reducing the H formation energies 0.22 eV from ab initio theoretical values. The predicted stretch-mode frequency for H bound to the Mg acceptor lies 5% above an observed infrared absorption attributed to this complex. More limited solubility measurements were carried out for nominally undoped material rendered n-type by donors provisionally identified as O impurities, and results agree well with theory after the aforementioned adjustment of formation energies. It is concluded that currently recognized H states and physical processes can account for the equilibrium, elevated-temperature behavior of H examined in this work. (C) 2000 American Institute of Physics. [S0021- 8979(00)07120-6]. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Myers, SM (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 40 TC 57 Z9 58 U1 0 U2 7 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 OCT 15 PY 2000 VL 88 IS 8 BP 4676 EP 4687 DI 10.1063/1.1309123 PG 12 WC Physics, Applied SC Physics GA 358HP UT WOS:000089552800034 ER PT J AU Yue, GZ Han, DX McNeil, LE Wang, Q AF Yue, GZ Han, DX McNeil, LE Wang, Q TI Characteristics of the low energy photoluminescence in mu c-Si films SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID MICROCRYSTALLINE SILICON; AMORPHOUS-SILICON; PHOTO-LUMINESCENCE; RECOMBINATION; RAMAN AB The temperature and excitation-intensity dependence of the similar to 0.9 eV photoluminescence (PL) band has been studied in several microcrystalline silicon (mu c-Si) films with varied crystallinity. When the measurement temperature is increased from 15 to 180 K, the PL peak energy redshifts from 1.0 to 0.83 eV. The PL quenching of the intensity follows a model of carrier thermalization in an exponential band tail with a width of similar to 20 meV. The total PL intensity (I-PL) as a function of excitation intensity (I-ex) obeys a power law of I(PL)proportional to I-ex(gamma), where gamma approximate to 0.65 or 1 for high or low excitation intensity, respectively. The experimental results suggest that the similar to 0.9 eV PL band originates from radiative tail-to-tail transitions in the grain-boundary region in mu c-Si. (C) 2000 American Institute of Physics. [S0021-8979(00)06919-X]. C1 Univ N Carolina, Dept Phys & Astron, Chapel Hill, NC 27599 USA. Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Yue, GZ (reprint author), Univ N Carolina, Dept Phys & Astron, Chapel Hill, NC 27599 USA. NR 15 TC 11 Z9 11 U1 0 U2 1 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 OCT 15 PY 2000 VL 88 IS 8 BP 4904 EP 4906 AR PII [S0021-8979(00)06919-X] DI 10.1063/1.1289785 PG 3 WC Physics, Applied SC Physics GA 358HP UT WOS:000089552800070 ER PT J AU Garza, J Nichols, JA Dixon, DA AF Garza, J Nichols, JA Dixon, DA TI The role of the local-multiplicative Kohn-Sham potential on the description of occupied and unoccupied orbitals SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID DENSITY-FUNCTIONAL THEORY; EXCHANGE-CORRELATION POTENTIALS; SELF-INTERACTION CORRECTION; MODIFIED VIRTUAL ORBITALS; HARTREE-FOCK THEORY; EXCITATION-ENERGIES; ELECTRON-DENSITIES; WAVE-FUNCTIONS; MOLECULAR-SYSTEMS; SPIN-DENSITY AB The optimum local-multiplicative exchange potential was found using as input the Hartree-Fock electron density, for the molecular systems: H-2, LiH, HF, NH3, CH4, H2O, N-2, CO, F-2, C2H2 and C2H4. The Zhao and Parr method was used to obtain the local-multiplicative potential where the kinetic energy is minimized using a constrained-search formulation of density functional theory. Two orbital sets were compared, those obtained with the nonlocal Hartree-Fock potential and those obtained with the local-multiplicative potential, both sets yielding the same electron density. As expected, the highest occupied molecular orbital (HOMO) energy was similar in both orbital sets. In contrast, the virtual orbital energies, and in particular the lowest unoccupied molecular orbital (LUMO), exhibited considerable differences. The Hartree-Fock LUMO energy goes to zero in a complete basis set limit and to nearly zero with reasonably large basis sets (e.g., augmented triple zeta) with sufficient diffuse functions added. The LUMO provided by the local-multiplicative potential using the same large basis set goes to a bounded energy not equal to zero. The nonlocal Hartree-Fock potential generates a large gap between the HOMO and LUMO energies; this difference is equal to the negative of the HOMO energy at the complete basis set limit. Contrary to this behavior, the gap obtained with the local-multiplicative potential is a reasonable approximation to the lowest experimental vertical excitation energy. For some of the molecules tested, the ordering of the orbitals corresponding to the HF and local-multiplicative potential are different. (C) 2000 American Institute of Physics. [S0021-9606(00)30439-1]. C1 Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. Univ Autonoma Metropolitana Iztapalapa, Dept Quim, Div Ciencias Basicas & Ingn, Mexico City 09340, DF, Mexico. RP Garza, J (reprint author), Pacific NW Natl Lab, Environm Mol Sci Lab, POB 999, Richland, WA 99352 USA. EM david.dixon@pnl.gov RI Garza, Jorge/H-9395-2016; Garza-Olguin, Jorge/N-3106-2016; OI Garza, Jorge/0000-0003-4249-6078; Garza-Olguin, Jorge/0000-0003-4249-6078; Nichols, Jeffrey/0000-0001-5454-9726 NR 94 TC 39 Z9 39 U1 0 U2 5 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 OCT 15 PY 2000 VL 113 IS 15 BP 6029 EP 6034 AR PII [S0021-9606(00)30439-1] DI 10.1063/1.1308547 PG 6 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 359WN UT WOS:000089635200003 ER PT J AU Bylaska, EJ Kawai, R Weare, JH AF Bylaska, EJ Kawai, R Weare, JH TI From small to large behavior: The transition from the aromatic to the Peierls regime in carbon rings SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID BOND-LENGTH ALTERNATION; DENSITY-FUNCTIONAL THEORY; ONE-DIMENSIONAL METALS; HARTREE-FOCK METHOD; MOLECULAR-STRUCTURE; CYCLIC POLYENES; GROUND-STATE; VIBRATIONAL FREQUENCIES; AB-INITIO; CLUSTERS AB Results of local density approximation (LDA) and Hartree-Fock (HF) calculations for even numbered monocyclic rings are reported. Small C-n rings satisfying n=4N+2 show aromatic stability with equal bond-length structures, whereas rings of size n=4N show antiaromatic destabilization with bond-length alternation. For large rings a transition, the Peierls transition, from aromatic and antiaromatic to nonaromatic behavior, takes place. Above the Peierls transition, both n=4N and n=4N+2 rings show bond-length alternation and no differences in stability. The critical size for the transition to nonaromatic behavior depends on the electron-phonon coupling strength and therefore depends on the choice of ab initio method. HF predicts nonaromatic behavior for ring sizes n=14 and above. Fully optimized LDA results are presented up to n=42, which still has a cumulenic structure. Calculations based on periodic infinite ring systems show that within LDA the onset of nonaromatic behavior does not occur until n=82. Experimental results suggest that aromatic behavior exists in these ring systems to at least n=22. The force constant for in-plane angle bending may also be estimated from these calculations and was found to be 0.022 kcal mol(-1) deg(-2) per atom, not a strong function of size beyond n=22, and in good agreement with experimental estimates. (C) 2000 American Institute of Physics. [S0021-9606(00)31339-3]. C1 Pacific NW Natl Lab, William R Wiley Environm Mol Sci Lab, Richland, WA 99352 USA. Univ Alabama, Dept Phys, Birmingham, AL 35294 USA. Univ Calif San Diego, Dept Chem, La Jolla, CA 92093 USA. RP Bylaska, EJ (reprint author), Pacific NW Natl Lab, William R Wiley Environm Mol Sci Lab, POB 99, Richland, WA 99352 USA. NR 61 TC 15 Z9 15 U1 0 U2 4 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 OCT 15 PY 2000 VL 113 IS 15 BP 6096 EP 6106 AR PII [S0021-9606(00)31339-3] DI 10.1063/1.1308556 PG 11 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 359WN UT WOS:000089635200011 ER PT J AU Bittererova, M Bowman, JM Peterson, K AF Bittererova, M Bowman, JM Peterson, K TI Quantum scattering calculations of the O(D-1) plus HCl reaction using a new ab initio potential and extensions of J-shifting SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID TOTAL ANGULAR-MOMENTUM; DEPENDENT WAVE-PACKET; RATE CONSTANTS; CROSS-SECTIONS; ENERGY SURFACE; H+O-2 REACTION; DYNAMICS; ROTATION; APPROXIMATIONS; COLLISIONS AB We report results of quantum wave packet calculations of the O(D-1)+HCl(v=0,j)--> ClO+H, OH+Cl, reactions for zero and nonzero total angular momentum, J, (using the centrifugal sudden approximation), and using a new fit to extensive ab initio calculations of a global potential [K. A. Peterson, S. Skokov, and J. M. Bowman, J. Chem. Phys. 111, 2445 (1999)]. Initial state-selected and cumulative reaction probabilities to form each set of products for J=0 are calculated by a direct summation of the initial state-selected reaction probabilities. We propose and test a simple energy-shifting approximation that relates the initial state-selected reaction probability for arbitrary j to the one for j=0. Extensions of standard J- and K-shifting methods are suggested and applied to both reaction channels. In doing this extension the adiabatic rotation approximation is used to determine the rotational barriers in the entrance and exit channels. The energy dependence of the reaction cross sections to form the two products is calculated for O(D-1)+HCl(v=0,j=0) using J- and K-shifting and compared at two translational energies to results of quasiclassical trajectory calculations. The thermal rate constants for the two reaction channels are calculated from 200 to 400 K and compared to experiment. (C) 2000 American Institute of Physics. [S0021-9606(00)00939-9]. C1 Emory Univ, Cherry L Emerson Ctr Sci Computat, Atlanta, GA 30322 USA. Emory Univ, Dept Chem, Atlanta, GA 30322 USA. Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. Washington State Univ, Dept Chem, Washington, DC USA. Slovak Univ Technol Bratislava, Dept Phys Chem, SK-81237 Bratislava, Slovakia. RP Bittererova, M (reprint author), Emory Univ, Cherry L Emerson Ctr Sci Computat, Atlanta, GA 30322 USA. EM bowman@euch4e.chem.emory.edu NR 60 TC 43 Z9 43 U1 2 U2 9 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 OCT 15 PY 2000 VL 113 IS 15 BP 6186 EP 6196 AR PII [S0021-9606(00)00939-9] PG 11 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 359WN UT WOS:000089635200022 ER PT J AU Dinh, LN Balooch, M LeMay, JD AF Dinh, LN Balooch, M LeMay, JD TI H2O outgassing properties of fumed and precipitated silica particles by temperature-programmed desorption SO JOURNAL OF COLLOID AND INTERFACE SCIENCE LA English DT Article DE silica; polymer; water outgassing; temperature-programmed desorption ID SURFACE; WATER; ADSORPTION; KINETICS AB Temperature-programmed desorption was performed at temperatures up to 850 K on as-received fumed and precipitated silica particles. Physisorbed water molecules on both types of silica had activation energies in the range of 38-61 kJ/mol. However, the activation energies of desorption for chemisorbed water varied from similar to 80 to >247 kJ/mol for fumed silica, Cab-O-Sil-M-7D, and similar to 96 to 155 kJ/mol for precipitated silica, Hi-Sil-233. Our results suggest that physisorbed water can be effectively pumped away at room temperature (or preferably at 320 K) in a matter of hours. Chemisorbed water with high activation energies of desorption (>126 kJ/mol) will not escape silica surfaces in 100 years even at 320 K, while a significant amount of the chemisorbed water with medium activation energies (80-109 kJ/mol) will leave the silica surfaces in that time span. Most of the chemisorbed water with activation energies <126 kJ/mol can be pumped away in a matter of days in a good vacuum environment at 500 K. We had previously measured about 0.1-0.4 wt% of water in silica-reinforced polysiloxane formulations containing 21% Cab-O-Sil-M-7D and similar to4% Hi-Sil-233. Comparing present results with these formulations, we conclude that the adsorbed H2O and the Si-OH bonds on the silica surfaces are the major contributors to water outgassing from these types of silica-filled polymers, (C) 2000 Academic Press. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Dinh, LN (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808,L-350, Livermore, CA 94551 USA. NR 9 TC 14 Z9 14 U1 0 U2 3 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0021-9797 J9 J COLLOID INTERF SCI JI J. Colloid Interface Sci. PD OCT 15 PY 2000 VL 230 IS 2 BP 432 EP 440 DI 10.1006/jcis.2000.7131 PG 9 WC Chemistry, Physical SC Chemistry GA 367PE UT WOS:000090070000024 ER PT J AU Torney, DC Wang, J AF Torney, DC Wang, J TI Systems of linear congruences with individual moduli SO LINEAR ALGEBRA AND ITS APPLICATIONS LA English DT Article DE systems of linear congruences; nonassociative algebra AB Consider an n x n matrix A, with integer elements, a column vector x of n integer indeterminates, and a column vector Q of n integers greater than unity. Ax module Q constitutes another n-vector b of nonnegative integers. The elemental feature of interest for such systems is whether they are regular (i.e., nonsingular): whether b uniquely determines x module Q. Let P-sigma denote the permutation matrix corresponding to a permutation sigma of {1, 2,..., n}. Then, for the special case of all pairs of elements of Q having the same greatest common factor, it is established that regularity obtains if and only if there exists a permutation sigma so that P(sigma)Ap(sigma)(T) is a triangular matrix with each element on the main diagonal coprime to its respective modulus (from P(sigma)Q). To resolve systems with general Q, a set of moduli is first derived from each original modulus by factoring it into prime-power factors. We introduce a corresponding regularity-preserving transformation of A and Q into an A' and Q': the latter containing, exclusively, prime-power moduli. Elementary transformations of A' preserving regularity module Q'-denoted equivalences-are introduced. A' is shown to be regular module Q' if and only if there exists a permutation sigma so that P(sigma)A'P-sigma(T) is equivalent to a triangular matrix, having each element on the main diagonal coprime to its respective modulus (from P(sigma)Q'). Whence, regularity is fully resolved for general systems. An algorithm for solving an arbitrary regular system Ax = b (mod Q) is, furthermore, implicit in these results, (C) 2000 Elsevier Science Inc. All rights reserved. AMS classification: Primary 11D79; Secondary 11A07; 14D99; 15A36. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Dalian Univ Technol, Inst Math Sci, Dept Math Appl, Dalian 116024, Peoples R China. RP Torney, DC (reprint author), Univ Calif Los Alamos Natl Lab, T-10,MS K710, Los Alamos, NM 87545 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0024-3795 J9 LINEAR ALGEBRA APPL JI Linear Alg. Appl. PD OCT 15 PY 2000 VL 318 IS 1-3 BP 195 EP 208 DI 10.1016/S0024-3795(00)00173-7 PG 14 WC Mathematics, Applied; Mathematics SC Mathematics GA 363NJ UT WOS:000089841200014 ER PT J AU Jiang, HG Zhu, YT Butt, DP Alexandrov, IV Lowe, TC AF Jiang, HG Zhu, YT Butt, DP Alexandrov, IV Lowe, TC TI Microstructural evolution, microhardness and thermal stability of HPT-processed Cu SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article DE HPT; copper; microstructure; microhardness; evolution; thermal stability ID SEVERE PLASTIC-DEFORMATION; CHANNEL ANGULAR EXTRUSION; RESOLUTION ELECTRON-MICROSCOPY; SUBMICROMETER GRAIN-SIZE; HALL-PETCH RELATIONSHIP; AL-MG ALLOY; NANOCRYSTALLINE COPPER; CALORIMETRIC MEASUREMENTS; BOUNDARY STRUCTURE; BEHAVIOR AB Coarse-grained copper was subject to high-pressure torsion (HPT) and thermal treatment to study the effects of increasing amounts of deformation and subsequent annealing on the evolution of microstructure and microhardness. Cellular subgrains with low-angle grain boundaries were first formed at low strain. Some of the low-angle subgrain boundaries transformed to high-angle grain boundaries at higher strains, refining the average grain size from 200 mu m to 150 nm. X-ray diffraction patterns showed the formation of crystallographic texture. Microhardness increased monotonically with increasing torsional strain. High internal stress and nonequilibrium grain boundaries were observed in unannealed samples. Annealing as-deformed samples at temperatures as low as 50 degrees C decreased the microhardness, indicating a very low thermal stability of the deformation induced microstructures. Differential scanning calorimetry (DSC) revealed an exothermal peak between 180 and 280 degrees C, caused by recrystallization. Annealing twins were also formed during recrystallization. (C) 2000 Elsevier Science S.A. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. Ufa State Aviat Tech Univ, Inst Phys Adv Mat, Ufa 450000, Russia. RP Zhu, YT (reprint author), Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. RI Zhu, Yuntian/B-3021-2008; Butt, Darryl/B-7480-2008 OI Zhu, Yuntian/0000-0002-5961-7422; Butt, Darryl/0000-0003-4501-8864 NR 74 TC 224 Z9 230 U1 16 U2 87 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 OCT 15 PY 2000 VL 290 IS 1-2 BP 128 EP 138 DI 10.1016/S0921-5093(00)00919-9 PG 11 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 345YA UT WOS:000088841800015 ER PT J AU Sharif, AA Misra, A Petrovic, JJ Mitchell, TE AF Sharif, AA Misra, A Petrovic, JJ Mitchell, TE TI Dislocation motion in erbia single crystals SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article DE erbium oxide; slip systems; shear strength; burgers vector; dislocation dissociation ID CREEP AB Dislocation motion during high-temperature deformation of erbia single crystals has been investigated. Compressive deformation alone [111], [(1) over bar (1) over bar 2], [(1) over bar 10] and [123] at 1640 degrees C resulted in slip on {110} planes. The Burgers vector was determined to be (b) over right arrow=1/2[1 (1) over bar 1]. Dislocations with such a large Burgers vector (9.1 Angstrom), can dissociate into 1/4[1 (1) over bar 0] and 1/4(1 (1) over bar 2) partials. The critical resolved shear stress of the samples at 1640 degrees C was estimated to be approximate to 38 MPa. Cleavage at room temperature was found to be on {111} plants. (C) 2000 Published by Elsevier Science S.A. C1 Univ Calif Los Alamos Natl Lab, Mat Sci & Technol Div, Los Alamos, NM 87544 USA. RP Sharif, AA (reprint author), Univ Calif Los Alamos Natl Lab, Mat Sci & Technol Div, MS K765, Los Alamos, NM 87544 USA. RI Misra, Amit/H-1087-2012 NR 16 TC 0 Z9 0 U1 0 U2 2 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0921-5093 J9 MAT SCI ENG A-STRUCT JI Mater. Sci. Eng. A-Struct. Mater. Prop. Microstruct. Process. PD OCT 15 PY 2000 VL 290 IS 1-2 BP 164 EP 170 DI 10.1016/S0921-5093(00)00943-6 PG 7 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA 345YA UT WOS:000088841800019 ER PT J AU Hadi, MZ Coleman, MA Fidelis, K Mohrenweiser, HW Wilson, DM AF Hadi, MZ Coleman, MA Fidelis, K Mohrenweiser, HW Wilson, DM TI Functional characterization of Ape1 variants identified in the human population SO NUCLEIC ACIDS RESEARCH LA English DT Article ID HUMAN APURINIC ENDONUCLEASE; BASE-EXCISION-REPAIR; REDUCED DNA-REPAIR; AMYOTROPHIC-LATERAL-SCLEROSIS; BENZOPYRENE DIOL EPOXIDE; ABASIC SITE ANALOGS; BREAST-CANCER; CELL CARCINOMA; ENZYME HAP1; LUNG-CANCER AB Apurinic/apyrimidinic (AP) sites are common mutagenic and cytotoxic DNA lesions. Ape1 is the major human repair enzyme for abasic sites and incises the phosphodiester backbone 5' to the lesion to initiate a cascade of events aimed at removing the AP moiety and maintaining genetic integrity. Through resequencing of genomic DNA from 128 unrelated individuals, and searching published reports and sequence databases, seven amino acid substitution variants were identified in the repair domain of human Ape1. Functional characterization revealed that three of the variants, L104R, E126D and R237A, exhibited similar to 40-60% reductions in specific incision activity. A fourth variant, D283G, is similar to the previously characterized mutant D283A found to exhibit similar to 10% repair capacity. The most common substitution (D148E; observed at an allele frequency of 0.38) had no impact on endonuclease and DNA binding activities, nor did a G306A substitution. A G241R variant showed slightly enhanced endonuclease activity relative to wild-type. In total, four of seven substitutions in the repair domain of Ape1 imparted reduced function. These reduced function variants may represent low penetrance human polymorphisms that associate with increased disease susceptibility. C1 Univ Calif Lawrence Livermore Natl Lab, Mol & Struct Biol Div, Livermore, CA 94551 USA. RP Wilson, DM (reprint author), Univ Calif Lawrence Livermore Natl Lab, Mol & Struct Biol Div, L-441,7000 East Ave, Livermore, CA 94551 USA. OI Coleman, Matthew/0000-0003-1389-4018 FU NCI NIH HHS [CA79056] NR 66 TC 160 Z9 170 U1 0 U2 7 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 OCT 15 PY 2000 VL 28 IS 20 BP 3871 EP 3879 DI 10.1093/nar/28.20.3871 PG 9 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 365MD UT WOS:000089954300005 PM 11024165 ER PT J AU Scavetta, R Thomas, CB Walsh, MA Szegedi, S Joachimiak, A Gumport, RI Churchill, MEA AF Scavetta, R Thomas, CB Walsh, MA Szegedi, S Joachimiak, A Gumport, RI Churchill, MEA TI Structure of RsrI methyltransferase, a member of the N6-adenine beta class of DNA methyltransferases SO NUCLEIC ACIDS RESEARCH LA English DT Article ID ADENOSYL-L-METHIONINE; AMINO-ACID-RESIDUES; ANOMALOUS DIFFRACTION; CRYSTAL-STRUCTURE; FUNCTIONAL ROLES; TARGET BASE; MOTIFS; CYTOSINE; PROTEINS; ECORI AB DNA methylation is important in cellular, developmental and disease processes, as well as in bacterial restriction-modification systems. Methylation of DNA at the amino groups of cytosine and adenine is a common mode of protection against restriction endonucleases afforded by the bacterial methyltransferases. The first structure of an N6-adenine methyltransferase belonging to the beta class of bacterial methyltransferases is described here. The structure of M . Rsrl from Rhodobacter sphaeroides, which methylates the second adenine of the GAATTC sequence, was determined to 1.75 Angstrom resolution using X-ray crystallography, Like other methyltransferases, the enzyme contains the methylase fold and has well-defined substrate binding pockets, The catalytic core most closely resembles the Pvull methyltransferase, a cytosine amino methyltransferase of the same beta group, The larger nucleotide binding pocket observed in M . Rsrl is expected because it methylates adenine, However, the most striking difference between the Rsrl methyltransferase and the other bacterial enzymes is the structure of the putative DNA target recognition domain, which is formed in part by two helices on an extended arm of the protein on the face of the enzyme opposite the active site. This observation suggests that a dramatic conformational change or oligomerization may take place during DNA binding and methylation. C1 Univ Colorado, Hlth Sci Ctr, Dept Pharmacol, Denver, CO 80262 USA. Univ Illinois, Dept Biochem, Urbana, IL 61801 USA. Argonne Natl Labs, Biosci Div, Struct Biol Ctr, Argonne, IL 60439 USA. RP Churchill, MEA (reprint author), Univ Colorado, Hlth Sci Ctr, Dept Pharmacol, 4200 E 9th Ave, Denver, CO 80262 USA. RI Churchill, Mair/C-5549-2014; Walsh, Martin/I-1566-2013 OI Churchill, Mair/0000-0003-0862-235X; Walsh, Martin/0000-0001-5683-1151 FU NCRR NIH HHS [P41 RR012408, RR12408-01A1]; NIGMS NIH HHS [R01 GM059456-04, GM 25621, GM-53163, R01 GM053163, R01 GM059456, R01 GM059456-02, R01 GM059456-03, R01 GM059456-05] NR 58 TC 61 Z9 63 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 OCT 15 PY 2000 VL 28 IS 20 BP 3950 EP 3961 DI 10.1093/nar/28.20.3950 PG 12 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 365MD UT WOS:000089954300015 PM 11024175 ER PT J AU Chang, SC Shrock, R AF Chang, SC Shrock, R TI Exact Potts model partition function on strips of the triangular lattice SO PHYSICA A LA English DT Article ID GROUND-STATE ENTROPY; CHROMATIC POLYNOMIALS; ASYMPTOTIC LIMITS; SQUARE LATTICE; FUNCTION ZEROS; ANTIFERROMAGNETS; GRAPHS; COMPLEX; FAMILIES; SERIES AB In this paper we present exact calculations of the partition function Z of the q-state Potts model and its generalization to real q, for arbitrary temperature on n-vertex strip graphs, of width L-y = 2 and arbitrary length, of the triangular lattice with free, cyclic, and Mobius longitudinal boundary conditions. These partition functions are equivalent to Tutte/Whitney polynomials for these graphs. The free energy is calculated exactly for the infinite-length limit of the graphs, and the thermodynamics is discussed. Considering the full generalization to arbitrary complex q and temperature, we determine the singular locus B in the corresponding C-2 space, arising as the accumulation set of partition function zeros as n --> infinity. In particular, we study the connection with the T = 0 limit of the Potts antiferromagnet where B reduces to the accumulation set of chromatic zeros. Comparisons an made with our previous exact calculation of Potts model partition functions for the corresponding strips of the square lattice. Our present calculations yield, as special cases, several quantities of graph-theoretic interest. (C) 2000 Published by Elsevier Science B.V. All rights reserved. C1 SUNY Stony Brook, CN Yang Inst Theoret Phys, Stony Brook, NY 11794 USA. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Shrock, R (reprint author), SUNY Stony Brook, CN Yang Inst Theoret Phys, Stony Brook, NY 11794 USA. NR 82 TC 46 Z9 46 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 OCT 15 PY 2000 VL 286 IS 1-2 BP 189 EP 238 DI 10.1016/S0378-4371(00)00225-9 PG 50 WC Physics, Multidisciplinary SC Physics GA 363JM UT WOS:000089832600013 ER PT J AU Qualls, JS Balicas, L Brooks, JS Harrison, N Montgomery, LK Tokumoto, M AF Qualls, JS Balicas, L Brooks, JS Harrison, N Montgomery, LK Tokumoto, M TI Competition between Pauli and orbital effects in a charge-density-wave system SO PHYSICAL REVIEW B LA English DT Article ID LOW-TEMPERATURE PHASE; MAGNETIC-FIELDS; ALPHA-(BEDT-TTF)(2)KHG(SCN)(4); STATE; ALPHA-(BEDT-TTF)(2)MHG(SCN)(4); C-13-NMR; DIAGRAM AB We present angular-dependent magnetotransport and magnetization measurements on alpha-(ET)(2)MHg(SCN)(4) compounds at high magnetic fields and low temperatures. We find that the low-temperature ground state undergoes two subsequent field-induced density-wave-type phase transitions above a critical angle of the magnetic field with respect to the crystallographic axes. This new phase diagram may be qualitatively described assuming a charge-density-wave ground state which undergoes field-induced transitions due to the interplay of Pauli and orbital effects. C1 Wake Forest Univ, Dept Phys, Winston Salem, NC 27109 USA. Florida State Univ, Natl High Magnet Field Lab, Tallahassee, FL 32306 USA. Univ Simon Bolivar, Dept Fis, Caracas 1080A, Venezuela. Univ Calif Los Alamos Natl Lab, Natl High Magnet Field Lab, Los Alamos, NM 87545 USA. Indiana Univ, Dept Chem, Bloomington, IN 47405 USA. Electrotech Lab, Tsukuba, Ibaraki 305, Japan. RP Qualls, JS (reprint author), Wake Forest Univ, Dept Phys, Winston Salem, NC 27109 USA. NR 33 TC 40 Z9 40 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 OCT 15 PY 2000 VL 62 IS 15 BP 10008 EP 10012 DI 10.1103/PhysRevB.62.10008 PG 5 WC Physics, Condensed Matter SC Physics GA 365YB UT WOS:000089977100037 ER PT J AU Magri, R Zunger, A AF Magri, R Zunger, A TI Anticrossing and coupling of light-hole and heavy-hole states in (001) GaAs/AlxGa1-xAs heterostructures SO PHYSICAL REVIEW B LA English DT Article ID SHORT-PERIOD SUPERLATTICES; COMMON-ATOM; GAAS/ALAS SUPERLATTICES; ELECTRONIC-STRUCTURE; OPTICAL ANISOTROPY; EXCITED-STATES; INTERFACE; SEMICONDUCTORS; PHOTOLUMINESCENCE; PSEUDOPOTENTIALS AB Heterostructures sharing a common atom such as AlAs/GaAs/AlAs have a D-2d point-group symmetry which allows the bulk-forbidden coupling between odd-parity light-hole states (e.g., lh1) and even-parity heavy-hole states (e.g., hh2). Continuum models, such as the commonly implemented ("standard model") k.p theory miss the correct D-2d symmetry and thus produce zero coupling at the zone center. We have used the atomistic empirical pseudopotential theory to study the lh1-hh2 coupling in (001) superlattices and quantum wells of GaAs/AlxGa1-xAs. By varying the Al concentration x of the barrier we scan a range of valence-band barrier heights DeltaE(v)(x). We find the following: (i) The lh1 and hh2 states anticross at rather large quantum wells width or superlattice periods 60 K+K- was used for identification. The phi/pi ratio is found to increase by a factor of 3.0 +/- 0.7 from inelastic p + p to central Pb + Pb. Significant enhancement in this ratio is also observed in subclasses of p + p events (characterized by high charged-particle multiplicity) as well as in the forward hemisphere of central p + Pb collisions. In Pb + Pb no shift or significant broadening of the phi -peak is seen. (C) 2000 Published by Elsevier Science B.V. C1 Univ Marburg, Fachbereich Phys, D-3550 Marburg, Germany. Univ Athens, Dept Phys, Athens, Greece. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Birmingham, Birmingham, W Midlands, England. Slovak Acad Sci, Inst Phys, Bratislava, Slovakia. Res Inst Particle & Nucl Phys, KFKI, Budapest, Hungary. CERN, CH-1211 Geneva, Switzerland. Inst Nucl Phys, Krakow, Poland. GSI Darmstadt, Gesell Schwerionenforsch GmbH, D-6100 Darmstadt, Germany. Univ Calif Davis, Davis, CA 95616 USA. Joint Inst Nucl Res, Dubna, Russia. Univ Frankfurt, Fachbereich Phys, D-6000 Frankfurt, Germany. Univ Houston, Houston, TX 77004 USA. Kent State Univ, Kent, OH 44242 USA. Univ Calif Los Angeles, Los Angeles, CA 90024 USA. Max Planck Inst Phys, D-80805 Munich, Germany. Inst Nucl Studies, PL-00681 Warsaw, Poland. Univ Warsaw, Inst Expt Phys, Warsaw, Poland. Univ Washington, Nucl Phys Lab, Seattle, WA 98195 USA. Yale Univ, New Haven, CT 06520 USA. Rudjer Boskovic Inst, Zagreb, Croatia. RP Puhlhofer, F (reprint author), Univ Marburg, Fachbereich Phys, Renthof 5, D-3550 Marburg, Germany. RI Barnby, Lee/G-2135-2010; Mischke, Andre/D-3614-2011; Voloshin, Sergei/I-4122-2013; Levai, Peter/A-1544-2014; Carr, Lincoln/E-3819-2016 OI Barnby, Lee/0000-0001-7357-9904; Carr, Lincoln/0000-0002-4848-7941 NR 32 TC 149 Z9 151 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 J9 PHYS LETT B JI Phys. Lett. B PD OCT 12 PY 2000 VL 491 IS 1-2 BP 59 EP 66 DI 10.1016/S0370-2693(00)01023-6 PG 8 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 366ZD UT WOS:000090035400009 ER PT J AU Seo, DK Corbett, JD AF Seo, DK Corbett, JD TI Synthesis, structure, and bonding of hypoelectronic SrIn4: Direct example of a dominant size effect in structure selection SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID CRYSTAL-STRUCTURE; BAAL4; GALLIUM; PHASE AB The structure of the new title compound, the same type as EuIn4, was refined in the monoclinic space group C2/m, with Z = 4. The compound exhibits a complex three-dimensional network built of four-and five-bonded indium atoms in fused and interbonded pentagons that sandwich the strontium atoms. Both electronic band-structure calculations and property measurements show that the compound is metallic. A detailed band-structure analysis indicates that the compound is hypoelectronic with a one-electron deficiency, but the In-In bonding is effectively optimized in the structure. The important role of cation size in the structure choice is noted in a comparative study of BaIn4, which has the closely related BaAl4-type structure in which barium atoms are sandwiched by six-membered rings. C1 US DOE, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Chem, Ames, IA 50011 USA. RP Corbett, JD (reprint author), US DOE, Ames Lab, Ames, IA 50011 USA. NR 33 TC 52 Z9 52 U1 1 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0002-7863 J9 J AM CHEM SOC JI J. Am. Chem. Soc. PD OCT 11 PY 2000 VL 122 IS 40 BP 9621 EP 9627 DI 10.1021/ja001886+ PG 7 WC Chemistry, Multidisciplinary SC Chemistry GA 367UB UT WOS:000090078900007 ER PT J AU Laskin, J Denisov, E Futrell, J AF Laskin, J Denisov, E Futrell, J TI A comparative study of collision-induced and surface-induced dissociation. 1. Fragmentation of protonated dialanine SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID INFRARED RADIATIVE DISSOCIATION; TRANSFORM MASS-SPECTROMETRY; GAS-PHASE; ACTIVATION-ENERGIES; INTERNAL ENERGY; AB-INITIO; ELECTROSPRAY-IONIZATION; POLYATOMIC IONS; PEPTIDE SPECTRA; GLYCINE AB Collision-induced and surface-induced dissociation of protonated dialanine (Ala-AlaH(+)) was studied using a 7 T Fourier Transform Ion Cyclotron Resonance Mass Spectrometer (FT-ICR MS). Energy-resolved fragmentation efficiency curves were obtained using both techniques. The results were modeled using RRKM/ QET formalism. The energetics and dynamics of the four primary and some secondary fragmentation pathways were determined from the RRKM modeling. Both multiple-collision CID and SID results could be reproduced within the same model. The strong correspondence of fragmentation efficiency curves obtained in the high-pressure CID and SID experiments indicates that the internal energy distributions of Ala-AlaH+ activated by multiple collisions and by surface impact are remarkably similar. C1 Pacific NW Natl Lab, William R Wiley Environm Mol Sci Lab, Richland, WA 99352 USA. RP Pacific NW Natl Lab, William R Wiley Environm Mol Sci Lab, POB 999,K8-96, Richland, WA 99352 USA. EM Julia.Laskin@pnl.gov RI Laskin, Julia/H-9974-2012 OI Laskin, Julia/0000-0002-4533-9644 NR 63 TC 107 Z9 109 U1 2 U2 12 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0002-7863 J9 J AM CHEM SOC JI J. Am. Chem. Soc. PD OCT 11 PY 2000 VL 122 IS 40 BP 9703 EP 9714 DI 10.1021/ja001384w PG 12 WC Chemistry, Multidisciplinary SC Chemistry GA 367UB UT WOS:000090078900017 ER PT J AU Wiederrecht, GP Svec, WA Wasielewski, MR Galili, T Levanon, H AF Wiederrecht, GP Svec, WA Wasielewski, MR Galili, T Levanon, H TI Novel mechanism for triplet state formation in short distance covalently linked radical ion pairs SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID ELECTRON-PARAMAGNETIC-RESONANCE; LIQUID-CRYSTALS; CHARGE SEPARATION; RES SPECTROSCOPY; REACTION CENTERS; ENERGY-TRANSFER; PHOTOSYNTHESIS; RECOMBINATION; MOLECULES; PULSES AB We report on a series of electron donor-acceptor (D-A) dyads that undergo singlet-initiated charge separation to produce a strongly spin coupled radical ion pair that subsequently undergoes charge recombination to produce a triplet state with unusual spin polarization. The molecules consist of either a 4-(N-piperidinyl)naphthalene-1,8-imide (6P) or 4-(N-pyrrolidinyl)-naphthalene-1,8-imide (5P) donor and a 1,8:4,5-naphthalenediimide (NI) or pyromellitimide (PI) acceptor. Selective photoexcitation of D within D--A produces the radical ion pair (1)[D-.+-A(.-)] quantitatively. This is followed by the formation of 3[D.+-A(.-)] via singlet-triplet mixing within the radical pair. Radical pair intersystem crossing (RP-ISC) leads to charge recombination to yield [D-(3*)A] or [3(*)D-A]. Time-resolved optical absorption and emission spectroscopy is coupled with EPR spectroscopy to characterize the mechanism of the nearly quantitative initial charge separation, reaction and the subsequent radical ion pair recombination reaction leading to the unusually spin polarized triplet state. These radical pairs also possess charge transfer emission bands that aid in the data analysis. The small number of previously reported covalent donor-acceptor systems that yield a triplet state from radical ion pair recombination use multistep charge separation reactions to achieve a greater than or equal to 20 Angstrom spacing between the oxidized donor and reduced acceptor. These examples have small exchange couplings, J, within the radical pair, so that S-To mixing between the radical pair energy levels occurs. In the strongly coupled systems described here, we show that the triplet states are formed by means of both S-T-0 and S-T-1 mixing, producing novel spin-polarized EPR spectra characterized by anisotropic spin lattice relaxation. C1 Northwestern Univ, Dept Chem, Evanston, IL 60208 USA. Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. Hebrew Univ Jerusalem, Farkas Ctr Light Induced Proc, IL-91904 Jerusalem, Israel. Hebrew Univ Jerusalem, Dept Phys Chem, IL-91904 Jerusalem, Israel. RP Wasielewski, MR (reprint author), Northwestern Univ, Dept Chem, 2145 Sheridan Rd, Evanston, IL 60208 USA. NR 27 TC 50 Z9 51 U1 2 U2 18 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 OCT 11 PY 2000 VL 122 IS 40 BP 9715 EP 9722 DI 10.1021/ja000662o PG 8 WC Chemistry, Multidisciplinary SC Chemistry GA 367UB UT WOS:000090078900018 ER PT J AU Incandela, J AF Incandela, J TI Hadron collider detectors SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 7th International Conference on Instrumentation for Colliding Beam Physics (INSTR99) CY NOV 15-19, 1999 CL HAMAMATSU, JAPAN SP Japanese Minist Educ Sci Sports & Culture, Inoue Fdn Sci, Res Fdn Opt Sci & Technol, Fdn High Energy Accelerator Sci DE ATLAS; CDF; CMS; D0; Higgs; supersymmetry ID TOP-QUARK PRODUCTION; TRANSVERSE ENERGY; COLLISIONS; ELECTRONS; FERMILAB; TRACKER AB Experiments are being prepared at the Fermilab Tevatron and the CERN Large Hadron Collider that promise to deliver extraordinary insights into the nature of spontaneous symmetry breaking, and the role of supersymmetry in our universe. This article reviews the goals, challenges, and designs of these experiments. (C) 2000 Published by Elsevier Science B.V. All rights reserved. C1 Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. RP Incandela, J (reprint author), Fermi Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. NR 22 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD OCT 11 PY 2000 VL 453 IS 1-2 BP 17 EP 24 DI 10.1016/S0168-9002(00)00601-X PG 8 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 366PA UT WOS:000090012700004 ER PT J AU Kaplan, DM AF Kaplan, DM TI Muon collider/neutrino factory: status and prospects SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 7th International Conference on Instrumentation for Colliding Beam Physics (INSTR99) CY NOV 15-19, 1999 CL HAMAMATSU, JAPAN SP Japanese Minist Educ Sci Sports & Culture, Inoue Fdn Sci, Res Fdn Opt Sci & Technol, Fdn High Energy Accelerator Sci ID TOPCOLOR-ASSISTED TECHNICOLOR; GEV ENERGY-RANGE; LSND EXPERIMENT; NEUTRINO; PHYSICS; RATIO; FLUX; OSCILLATIONS; KAMIOKANDE; SPECTRUM AB During the 1990s an international collaboration has been studying the possibility of constructing and operating a high-energy high-luminosity mu (+)mu (-) collider. Such a machine could be the approach of choice to extend our discovery reach beyond that of the LHC. More recently, a growing collaboration is exploring the potential of a stored-muon-beam "neutrino factory" to elucidate neutrino oscillations. A neutrino factory could be an attractive stepping-stone to a muon collider. Its construction, possibly feasible within the coming decade, could have substantial impact on neutrino physics. (C) 2000 Elsevier Science B.V. All rights reserved. C1 IIT, Chicago, IL 60616 USA. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. RP IIT, Chicago, IL 60616 USA. EM kaplan@fnal.gov NR 74 TC 7 Z9 7 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 EI 1872-9576 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD OCT 11 PY 2000 VL 453 IS 1-2 BP 37 EP 48 DI 10.1016/S0168-9002(00)00604-5 PG 12 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 366PA UT WOS:000090012700007 ER PT J AU Bozzi, C Carassiti, V Ramusino, AC Dittongo, S Folegani, M Piemontese, L Abbott, BK Breon, AB Clark, AR Dow, S Fan, Q Goozen, F Hernikl, C Karcher, A Kerth, LT Kipnis, I Kluth, S Lynch, G Levi, M Luft, P Luo, L Nyman, M Pedrali-Noy, M Roe, NA Zizka, G Roberts, D Barni, D Brenna, E Defendi, I Forti, A Giugni, D Lanni, F Palombo, F Vaniev, V Leona, A Mandelli, E Manfredi, PF Perazzo, A Re, V Angelini, C Batignani, G Bettarini, S Bondioli, M Bosi, F Calderini, G Carpinelli, M Dutra, F Forti, F Gagliardi, D Giorgi, MA Lusiani, A Mammini, P Morganti, M Morsani, F Paoloni, E Profeti, A Rama, M Rampino, G Rizzo, G Sandrelli, F Simi, G Triggiani, G Tritto, S Vitale, R Burchat, P Cheng, C Kirkby, D Meyer, T Roat, C Bona, M Bianchi, F Daudo, F Di Girolamo, B Gamba, D Giraudo, G Grosso, P Romero, A Smol, A Trapani, P Zanin, D Bosisio, L Della Ricca, G Lanceri, L Pompili, A Poropat, P Prest, M Rastelli, C Vallazza, E Vuagnin, G Hast, C Potter, EP Sharma, V Burke, S Callahan, D Campagnari, C Dahmes, B Eppich, A Hale, D Hall, K Hart, P Kuznetsova, N Kyre, S Levy, S Long, O May, J Richman, J Verkerke, W Witherell, M Beringer, J Eisner, AM Frey, A Grillo, A Grothe, M Johnson, R Spencer, E Turri, M Wilder, M Charles, E Elmer, P Nielsen, J Orejudos, W Scott, I Walsh, J Zobernig, H AF Bozzi, C Carassiti, V Ramusino, AC Dittongo, S Folegani, M Piemontese, L Abbott, BK Breon, AB Clark, AR Dow, S Fan, Q Goozen, F Hernikl, C Karcher, A Kerth, LT Kipnis, I Kluth, S Lynch, G Levi, M Luft, P Luo, L Nyman, M Pedrali-Noy, M Roe, NA Zizka, G Roberts, D Barni, D Brenna, E Defendi, I Forti, A Giugni, D Lanni, F Palombo, F Vaniev, V Leona, A Mandelli, E Manfredi, PF Perazzo, A Re, V Angelini, C Batignani, G Bettarini, S Bondioli, M Bosi, F Calderini, G Carpinelli, M Dutra, F Forti, F Gagliardi, D Giorgi, MA Lusiani, A Mammini, P Morganti, M Morsani, F Paoloni, E Profeti, A Rama, M Rampino, G Rizzo, G Sandrelli, F Simi, G Triggiani, G Tritto, S Vitale, R Burchat, P Cheng, C Kirkby, D Meyer, T Roat, C Bona, M Bianchi, F Daudo, F Di Girolamo, B Gamba, D Giraudo, G Grosso, P Romero, A Smol, A Trapani, P Zanin, D Bosisio, L Della Ricca, G Lanceri, L Pompili, A Poropat, P Prest, M Rastelli, C Vallazza, E Vuagnin, G Hast, C Potter, EP Sharma, V Burke, S Callahan, D Campagnari, C Dahmes, B Eppich, A Hale, D Hall, K Hart, P Kuznetsova, N Kyre, S Levy, S Long, O May, J Richman, J Verkerke, W Witherell, M Beringer, J Eisner, AM Frey, A Grillo, A Grothe, M Johnson, R Spencer, E Turri, M Wilder, M Charles, E Elmer, P Nielsen, J Orejudos, W Scott, I Walsh, J Zobernig, H TI The BaBar silicon vertex tracker SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 7th International Conference on Instrumentation for Colliding Beam Physics (INSTR99) CY NOV 15-19, 1999 CL HAMAMATSU, JAPAN SP Japanese Minist Educ Sci Sports & Culture, Inoue Fdn Sci, Res Fdn Opt Sci & Technol, Fdn High Energy Accelerator Sci DE SVT; Silicon Vertex Tracker; BaBar; silicon strip detectors AB The BaBar Silicon Vertex Tracker (SVT) is designed to provide the high-precision vertexing necessary for making measurements of CP violation at the SLAG B-Factory PEP-II. The instrument consists of five layers of double-sided silicon strip detectors and has been installed in the BaBar experiment and taking colliding beam data since May 1999. An overview of the design as well as performance and experience from the initial running will be presented. (C) 2000 Published by Elsevier Science B.V. All rights reserved. C1 Univ Wisconsin, Madison, WI 53706 USA. Ist Nazl Fis Nucl, Ferrara, Italy. Univ Ferrara, I-44100 Ferrara, Italy. Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. Univ Maryland, College Pk, MD 20742 USA. Ist Nazl Fis Nucl, I-20133 Milan, Italy. Univ Milan, Milan, Italy. Ist Nazl Fis Nucl, I-27100 Pavia, Italy. Univ Pavia, I-27100 Pavia, Italy. Univ Bergamo, Bergamo, Italy. Ist Nazl Fis Nucl, Pisa, Italy. Univ Pisa, Pisa, Italy. Stanford Univ, Stanford, CA 94305 USA. Ist Nazl Fis Nucl, I-10125 Turin, Italy. Univ Turin, Turin, Italy. Ist Nazl Fis Nucl, Trieste, Italy. Univ Trieste, Trieste, Italy. Univ Calif San Diego, San Diego, CA 92103 USA. Univ Calif Santa Barbara, Santa Barbara, CA 93106 USA. Univ Calif Santa Cruz, Santa Cruz, CA 95064 USA. RP Univ Wisconsin, Madison, WI 53706 USA. RI Forti, Francesco/H-3035-2011; Roe, Natalie/A-8798-2012; Lusiani, Alberto/N-2976-2015; Lusiani, Alberto/A-3329-2016; Della Ricca, Giuseppe/B-6826-2013 OI Forti, Francesco/0000-0001-6535-7965; Lusiani, Alberto/0000-0002-6876-3288; Lusiani, Alberto/0000-0002-6876-3288; Della Ricca, Giuseppe/0000-0003-2831-6982 NR 7 TC 7 Z9 7 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 EI 1872-9576 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD OCT 11 PY 2000 VL 453 IS 1-2 BP 78 EP 83 DI 10.1016/S0168-9002(00)00609-4 PG 6 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 366PA UT WOS:000090012700012 ER PT J AU Affolder, A Azzi-Bacchetta, P Bacchetta, N Barker, G Barbaro-Galtieri, A Basti, A Bedeschi, F Bisello, D Blusk, S Caskey, WP Chiarelli, G Connolly, A Demina, R Ely, R Field, R Garcia-Sciveres, M Giolo, K Goldstein, D Goldstein, J Grim, GP Guerzoni, M Haas, R Haber, C Hara, K Hartmann, F Heiss, A Hill, C Hrycyk, M Incandela, J Kato, Y Knoblauch, D Kruse, M Lander, RL Lei, CM Leonardi, GL Leone, S Miyazaki, Y Moggi, A Muller, T Munar-Ara, A Okusawa, T Palmonari, F Paulini, M Piacentino, G Pellett, DE Raffaelli, F Roederer, F Saltzberg, D Shimojima, M Stuart, D Suzuki, H Takano, T Takikawa, K Tanaka, M Taniguchi, Y Tipton, P Turini, N Volobouev, I Wenzel, H Wilkes, TD Yao, W Yoshida, T Zetti, F Zucchelli, S AF Affolder, A Azzi-Bacchetta, P Bacchetta, N Barker, G Barbaro-Galtieri, A Basti, A Bedeschi, F Bisello, D Blusk, S Caskey, WP Chiarelli, G Connolly, A Demina, R Ely, R Field, R Garcia-Sciveres, M Giolo, K Goldstein, D Goldstein, J Grim, GP Guerzoni, M Haas, R Haber, C Hara, K Hartmann, F Heiss, A Hill, C Hrycyk, M Incandela, J Kato, Y Knoblauch, D Kruse, M Lander, RL Lei, CM Leonardi, GL Leone, S Miyazaki, Y Moggi, A Muller, T Munar-Ara, A Okusawa, T Palmonari, F Paulini, M Piacentino, G Pellett, DE Raffaelli, F Roederer, F Saltzberg, D Shimojima, M Stuart, D Suzuki, H Takano, T Takikawa, K Tanaka, M Taniguchi, Y Tipton, P Turini, N Volobouev, I Wenzel, H Wilkes, TD Yao, W Yoshida, T Zetti, F Zucchelli, S TI Intermediate silicon layers detector for the CDF experiment SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 7th International Conference on Instrumentation for Colliding Beam Physics (INSTR99) CY NOV 15-19, 1999 CL HAMAMATSU, JAPAN SP Japanese Minist Educ Sci Sports & Culture, Inoue Fdn Sci, Res Fdn Opt Sci & Technol, Fdn High Energy Accelerator Sci AB The Intermediate Silicon Layers (ISL) detector is currently being built as part of the CDF II detector upgrade project. The ISL detector will significantly improve tracking in the central region ana, together with the Silicon Vertex detector, provide stand-alone 3D track information in the forward/backward regions. In this article, we present the quality of the production sensors manufactured by Hamamatsu Photonics, which account for roughly half of the silicon sensors used in the ISL detector. (C) 2000 Published by Elsevier Science B.V. All rights reserved. C1 Univ Tsukuba, Tsukuba, Ibaraki 305, Japan. Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. Univ Padua, I-35131 Padua, Italy. Ist Nazl Fis Nucl, Sez Padova, I-35131 Padua, Italy. Univ Karlsruhe, D-76148 Karlsruhe, Germany. Univ Pisa, I-56010 Pisa, Italy. Ist Nazl Fis Nucl, Sez Pisa, I-56010 Pisa, Italy. Univ Rochester, Rochester, NY USA. Univ Calif Davis, Davis, CA 95616 USA. Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Florida, Gainesville, FL 32611 USA. Univ Calif Los Angeles, Los Angeles, CA 90024 USA. Univ Bologna, I-40126 Bologna, Italy. Ist Nazl Fis Nucl, Sez Bologna, I-40126 Bologna, Italy. Osaka City Univ, Osaka 588, Japan. Univ Cassino, I-03043 Cassino, Italy. RP Shimojima, M (reprint author), Univ Tsukuba, Tsukuba, Ibaraki 305, Japan. RI Azzi, Patrizia/H-5404-2012; Chiarelli, Giorgio/E-8953-2012; Hill, Christopher/B-5371-2012; Paulini, Manfred/N-7794-2014; OI Azzi, Patrizia/0000-0002-3129-828X; Chiarelli, Giorgio/0000-0001-9851-4816; Hill, Christopher/0000-0003-0059-0779; Paulini, Manfred/0000-0002-6714-5787; Turini, Nicola/0000-0002-9395-5230; Goldstein, Joel/0000-0003-1591-6014 NR 5 TC 117 Z9 117 U1 0 U2 6 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 OCT 11 PY 2000 VL 453 IS 1-2 BP 84 EP 88 DI 10.1016/S0168-9002(00)00610-0 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 366PA UT WOS:000090012700013 ER PT J AU Takahashi, J Bellwied, R Beuttenmuller, R Caines, H Chen, W Dyke, H Hoffmann, GW Humanic, T Jensen, P Kuczewski, P Leonhardt, W Li, Z Lynn, D Lo Curto, G Minor, R Schambach, J Soja, R Sugarbaker, E Willson, RM Pandey, SU AF Takahashi, J Bellwied, R Beuttenmuller, R Caines, H Chen, W Dyke, H Hoffmann, GW Humanic, T Jensen, P Kuczewski, P Leonhardt, W Li, Z Lynn, D Lo Curto, G Minor, R Schambach, J Soja, R Sugarbaker, E Willson, RM Pandey, SU TI Silicon drift detectors as tracking devices SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 7th International Conference on Instrumentation for Colliding Beam Physics (INSTR99) CY NOV 15-19, 1999 CL HAMAMATSU, JAPAN SP Japanese Minist Educ Sci Sports & Culture, Inoue Fdn Sci, Res Fdn Opt Sci & Technol, Fdn High Energy Accelerator Sci ID STAR EXPERIMENT; STRANGE AB Silicon drift detectors provide unambiguous two-dimensional position information for charged particle detection in a single detector layer. Like most other semi-conductor technologies, Silicon drift detectors are presently used in vertexing detectors. By taking into account, the drastic reduction in channel count compared to other silicon-based devices this specific technology is also well suited for large coverage tracking detectors. The first larger area Silicon Drift Tracker (6.3 cm x 6.3 cm) was developed as the inner tracking detector (SVT) of the STAR experiment at the RHIC collider. Advantages and limitations of this detector will be discussed. Recent results of detector performance based on an application in a heavy ion fixed target experiment at the BNL-AGS (E896) are presented. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Brookhaven Natl Lab, Instrumentat Div, Upton, NY 11973 USA. Wayne State Univ, Detroit, MI 48201 USA. Ohio State Univ, Columbus, OH 43210 USA. Univ Texas, Austin, TX 78712 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Takahashi, J (reprint author), Brookhaven Natl Lab, Instrumentat Div, Bldg 535B,POB 500, Upton, NY 11973 USA. RI Takahashi, Jun/B-2946-2012 OI Takahashi, Jun/0000-0002-4091-1779 NR 13 TC 6 Z9 6 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD OCT 11 PY 2000 VL 453 IS 1-2 BP 131 EP 135 DI 10.1016/S0168-9002(00)00618-5 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 366PA UT WOS:000090012700021 ER PT J AU Lincoln, D AF Lincoln, D CA D O Collaboration TI A large statistics study of the performance and yields of generation-6 VLPCs (HISTE-VI) SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 7th International Conference on Instrumentation for Colliding Beam Physics (INSTR99) CY NOV 15-19, 1999 CL HAMAMATSU, JAPAN SP Japanese Minist Educ Sci Sports & Culture, Inoue Fdn Sci, Res Fdn Opt Sci & Technol, Fdn High Energy Accelerator Sci ID SCINTILLATING-FIBER-DETECTOR AB In this paper, the DO collaboration reports on the test results of 142 880 VLPC pixels. We have explored the space of operating conditions and found good performance at a temperature of 9 K and an average bias voltage of 7 V. Preliminary tests have shown an average quantum efficiency of 80% and a gain of 20 000-60 000. Tests have shown that the devices can be made to work at very high rates. The pixel-to-pixel variation within a chip is manageable, allowing one to assemble like-performing VLPC chips into cassettes containing 1024 pixels each. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. RP Lincoln, D (reprint author), Fermi Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. NR 8 TC 7 Z9 7 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD OCT 11 PY 2000 VL 453 IS 1-2 BP 177 EP 181 DI 10.1016/S0168-9002(00)00626-4 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 366PA UT WOS:000090012700028 ER PT J AU Acosta, D Apollinari, G Blomquist, J Breedon, R Bondar, N Bonushkin, Y Borissov, E Bujak, A Bylsma, B Chester, N Chrisman, D Cline, D Dolinsky, S Durkin, S Eartly, D Ferguson, T Feyzi, F Gilmore, J Gorn, L Gorn, W Gu, J Gutay, L Hauser, J Hershman, S Hoftiezer, J Kisselev, O Ko, W Korienek, J Korytov, A Kubic, J Layter, J Ling, TY Loveless, R Lusin, S Matthey, C Matveev, M Medved, S Mitselmakher, G Otwinowski, S Padley, P Petriello, F Pischalnikov, Y Prokofiev, O Razmyslovich, V Reeder, D Roberts, J Robl, P Rush, C Santiard, JC Sedov, S Smith, B Sobolev, S Soulimov, V Tannenbaum, B Terentyev, N Vorobyov, A Yarba, V AF Acosta, D Apollinari, G Blomquist, J Breedon, R Bondar, N Bonushkin, Y Borissov, E Bujak, A Bylsma, B Chester, N Chrisman, D Cline, D Dolinsky, S Durkin, S Eartly, D Ferguson, T Feyzi, F Gilmore, J Gorn, L Gorn, W Gu, J Gutay, L Hauser, J Hershman, S Hoftiezer, J Kisselev, O Ko, W Korienek, J Korytov, A Kubic, J Layter, J Ling, TY Loveless, R Lusin, S Matthey, C Matveev, M Medved, S Mitselmakher, G Otwinowski, S Padley, P Petriello, F Pischalnikov, Y Prokofiev, O Razmyslovich, V Reeder, D Roberts, J Robl, P Rush, C Santiard, JC Sedov, S Smith, B Sobolev, S Soulimov, V Tannenbaum, B Terentyev, N Vorobyov, A Yarba, V TI Large CMS cathode strip chambers: design and performance SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 7th International Conference on Instrumentation for Colliding Beam Physics (INSTR99) CY NOV 15-19, 1999 CL HAMAMATSU, JAPAN SP Japanese Minist Educ Sci Sports & Culture, Inoue Fdn Sci, Res Fdn Opt Sci & Technol, Fdn High Energy Accelerator Sci AB Presented are the main design features of the large Cathode Strip Chambers (CSCs) for the CMS Endcap Muon System as well as the performance results obtained with the two full-scale 3.4 x 1.5 m(2) six-plane prototypes. The prototype performance was within the baseline requirements: (a) higher than 99% efficiency of muon track finding at the trigger level with more than 92% probability for bunch crossing identification and better than 2 mm spatial resolution, and fb) better than 150 mum spatial resolution in off-line. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Florida, Dept Phys, Gainesville, FL 32611 USA. Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Calif Davis, Davis, CA 95616 USA. St Petersburg Nucl Phys Inst, St Petersburg, Russia. Univ Calif Los Angeles, Los Angeles, CA 90024 USA. Purdue Univ, W Lafayette, IN 47907 USA. Ohio State Univ, Athens, OH 45701 USA. Univ Calif Riverside, Riverside, CA 92521 USA. Carnegie Mellon Univ, Pittsburgh, PA 15213 USA. Univ Wisconsin, Madison, WI 53706 USA. Rice Univ, Houston, TX 77251 USA. CERN, CH-1211 Geneva 23, Switzerland. RP Korytov, A (reprint author), Univ Florida, Dept Phys, POB 118440,Williamson Hall 215, Gainesville, FL 32611 USA. RI Ferguson, Thomas/O-3444-2014; OI Ferguson, Thomas/0000-0001-5822-3731; Dolinsky, Sergei/0000-0002-2789-453X NR 6 TC 14 Z9 17 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 OCT 11 PY 2000 VL 453 IS 1-2 BP 182 EP 187 DI 10.1016/S0168-9002(00)00627-6 PG 6 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 366PA UT WOS:000090012700029 ER PT J AU Va'vra, J AF Va'vra, J TI Particle identification methods in high-energy physics SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 7th International Conference on Instrumentation for Colliding Beam Physics (INSTR99) CY NOV 15-19, 1999 CL HAMAMATSU, JAPAN SP Japanese Minist Educ Sci Sports & Culture, Inoue Fdn Sci, Res Fdn Opt Sci & Technol, Fdn High Energy Accelerator Sci DE particle identification; energy loss; Cherenkov detectors; single photon imaging; PMT; HPD; RICH; aerogel ID HERA-B RICH; HELIUM GAS-MIXTURES; CHERENKOV DETECTOR; RELATIVISTIC RISE; CSI PHOTOCATHODE; PHOTON DETECTOR; IONIZATION LOSS; DRIFT CHAMBERS; FOCUSING DIRC; II DETECTOR AB This paper deals with two major particle identification methods: dE/dx and Cherenkov detection. In the first method, we systematically compare existing dE/dx data with various predictions available in the literature, such as the Particle Data Group recommendation, and judge the overall consistency. To my knowledge, such comparison was not done yet in a published form for the gaseous detectors used in high-energy physics. As for the second method, there are two major Cherenkov light detection techniques: the threshold and the Ring imaging methods. We discuss the recent trend in these techniques. (C) 2000 Published by Elsevier Science B.V. C1 Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Va'vra, J (reprint author), Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. NR 110 TC 14 Z9 14 U1 1 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD OCT 11 PY 2000 VL 453 IS 1-2 BP 262 EP 278 DI 10.1016/S0168-9002(00)00644-6 PG 17 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 366PA UT WOS:000090012700046 ER PT J AU Akiba, Y Begay, R Burwood-Hoy, J Chappell, RB Crook, DW Ebisu, K Emery, MS Ferrierra, J Frawley, AD Hamagaki, H Hara, H Hayano, RS Hemmick, TK Hibino, M Hutter, R Kennedy, M Kikuchi, J Matsumoto, T Moscone, GG Nagasaka, Y Nishimura, S Oyama, K Sakaguchi, T Salomone, S Shigaki, K Tanaka, Y Walker, JW Wintenberg, AL Young, GR AF Akiba, Y Begay, R Burwood-Hoy, J Chappell, RB Crook, DW Ebisu, K Emery, MS Ferrierra, J Frawley, AD Hamagaki, H Hara, H Hayano, RS Hemmick, TK Hibino, M Hutter, R Kennedy, M Kikuchi, J Matsumoto, T Moscone, GG Nagasaka, Y Nishimura, S Oyama, K Sakaguchi, T Salomone, S Shigaki, K Tanaka, Y Walker, JW Wintenberg, AL Young, GR TI The PHENIX ring imaging Cherenkov detector SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 7th International Conference on Instrumentation for Colliding Beam Physics (INSTR99) CY NOV 15-19, 1999 CL HAMAMATSU, JAPAN SP Japanese Minist Educ Sci Sports & Culture, Inoue Fdn Sci, Res Fdn Opt Sci & Technol, Fdn High Energy Accelerator Sci AB The PHENIX experiment at RHIC is primarily a lepton and photon detector. Electron detection takes place in the two central arms of PHENIX, with the primary electron identifier in each arm being a ring imaging Cherenkov detector. This paper contains a description of the two identical RICH detectors and of their expected performance. (C) 2000 Published by Elsevier Science B.V. All rights reserved. C1 Florida State Univ, Tallahassee, FL 32306 USA. SUNY Stony Brook, Stony Brook, NY 11794 USA. High Energy Accelerator Res Org, Tsukuba, Ibaraki 3050801, Japan. Nagasaki Inst Appl Sci, Nagasaki 8510193, Japan. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Univ Tokyo, Ctr Nucl Study, Tokyo 1880002, Japan. Univ Tokyo, Dept Phys, Tokyo 1130033, Japan. Waseda Univ, Tokyo 1698555, Japan. RP Frawley, AD (reprint author), Florida State Univ, Tallahassee, FL 32306 USA. RI Hayano, Ryugo/F-7889-2012; HAMAGAKI, HIDEKI/G-4899-2014 OI Hayano, Ryugo/0000-0002-1214-7806; NR 2 TC 4 Z9 4 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD OCT 11 PY 2000 VL 453 IS 1-2 BP 279 EP 283 DI 10.1016/S0168-9002(00)00645-8 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 366PA UT WOS:000090012700047 ER PT J AU Adam, I Aleksan, R Aston, D Benkebil, M Bernard, D Bonneaud, G Briand, H Brochard, F Brown, DN Chauveau, J Cohen-Tanugi, J Convery, M David, P De Domenico, G de Lesquen, A Emery, S Ferrag, S Gaidot, A Geld, T de Monchenault, GH Hamon, O Hoecker, A Kadel, RW Kadyk, J Kalelkar, M Le Diberder, F London, G Lu, A Lutz, AM Lynch, G Mancinelli, G Martinez-Vidal, F Meadows, BT Plano, R Plaszczynski, S Pripstein, M Ratcliff, BN Roos, L Roussot, E Salnikov, A Schune, MH Schwiening, J Shelkov, V Sokoloff, MD Spanier, S Stark, J Telnov, A Thiebaux, C Valassi, A Vasileaidis, G Vasseur, G Va'vra, J Verderi, M Wilson, RJ Wormser, G Yeche, C Yellin, S AF Adam, I Aleksan, R Aston, D Benkebil, M Bernard, D Bonneaud, G Briand, H Brochard, F Brown, DN Chauveau, J Cohen-Tanugi, J Convery, M David, P De Domenico, G de Lesquen, A Emery, S Ferrag, S Gaidot, A Geld, T de Monchenault, GH Hamon, O Hoecker, A Kadel, RW Kadyk, J Kalelkar, M Le Diberder, F London, G Lu, A Lutz, AM Lynch, G Mancinelli, G Martinez-Vidal, F Meadows, BT Plano, R Plaszczynski, S Pripstein, M Ratcliff, BN Roos, L Roussot, E Salnikov, A Schune, MH Schwiening, J Shelkov, V Sokoloff, MD Spanier, S Stark, J Telnov, A Thiebaux, C Valassi, A Vasileaidis, G Vasseur, G Va'vra, J Verderi, M Wilson, RJ Wormser, G Yeche, C Yellin, S TI Status of the DIRC detector at BaBar: early operational experience SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 7th International Conference on Instrumentation for Colliding Beam Physics (INSTR99) CY NOV 15-19, 1999 CL HAMAMATSU, JAPAN SP Japanese Minist Educ Sci Sports & Culture, Inoue Fdn Sci, Res Fdn Opt Sci & Technol, Fdn High Energy Accelerator Sci DE Ratcliff; Cherenkov; DIRC; BaBar detector; RICH counter ID CHERENKOV DETECTOR AB A novel type of Cherenkov ring imaging particle identification system (DIRC) based on the detection of ring images produced in long, fused silica radiator bars is being used to provide hadronic particle identification in the BaBar detector at PEP-TI. The DIRC concept, design, fabrication, and initial performance will be briefly described. The DIRC is now fully commissioned, and has been operating in the BaBar detector on beam line at the PEP-II B Factory since late Spring 1999. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. CEA Saclay, DAPNIA, SPP, F-91191 Gif Sur Yvette, France. Univ Paris Sud, LAL, F-91405 Orsay, France. Ecole Polytech, LPNHE, F-91128 Palaiseau, France. Univ Paris 06, LPNHE, F-75252 Paris 05, France. Univ Paris 07, LPNHE, F-75252 Paris 05, France. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Cincinnati, Dept Phys, Cincinnati, OH 45221 USA. Rutgers State Univ, Dept Phys, Piscataway, NJ 08855 USA. Univ Calif Santa Barbara, Dept Phys, Santa Barbara, CA 93106 USA. Colorado State Univ, Dept Phys, Ft Collins, CO 80523 USA. RP Ratcliff, BN (reprint author), Stanford Univ, Stanford Linear Accelerator Ctr, POB 20450, Stanford, CA 94309 USA. RI Valassi, Andrea/K-7506-2012; Martinez Vidal, F*/L-7563-2014; OI Valassi, Andrea/0000-0001-9322-9565; Martinez Vidal, F*/0000-0001-6841-6035; Wilson, Robert/0000-0002-8184-4103 NR 10 TC 2 Z9 2 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 OCT 11 PY 2000 VL 453 IS 1-2 BP 301 EP 307 DI 10.1016/S0168-9002(00)00649-5 PG 7 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 366PA UT WOS:000090012700051 ER PT J AU Sakaguchi, T Akiba, Y Ebisu, K Frank, S Hamagaki, H Hara, H Hayano, RS Hibino, M Jones, JP Kametani, S Kikuchi, J Matsumoto, T Moscone, CG Nishimura, S Oyama, K Shigaki, K Tanaka, Y Ushiroda, T Walker, JW Wintenberg, AL Young, GR AF Sakaguchi, T Akiba, Y Ebisu, K Frank, S Hamagaki, H Hara, H Hayano, RS Hibino, M Jones, JP Kametani, S Kikuchi, J Matsumoto, T Moscone, CG Nishimura, S Oyama, K Shigaki, K Tanaka, Y Ushiroda, T Walker, JW Wintenberg, AL Young, GR TI Development of front end electronics for PHENIX RICH SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 7th International Conference on Instrumentation for Colliding Beam Physics (INSTR99) CY NOV 15-19, 1999 CL HAMAMATSU, JAPAN SP Japanese Minist Educ Sci Sports & Culture, Inoue Fdn Sci, Res Fdn Opt Sci & Technol, Fdn High Energy Accelerator Sci ID IMAGING CHERENKOV DETECTOR AB A new front-end electronics (FEE) for PHENIX Ring Imaging Cherenkov Detector (RICH) has been developed. It consists of custom-made Backplane, Controller module. Readout module and AMU/ADC module, which are capable of processing signals from 5120 Photo-Multiplier Tubes (PMTs). Several tests have been carried out, and RICH FEE was proved to satisfy the requirement of PHENIX experiment. The charge spectrum due to single photo-electron was successfully observed as well. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Tokyo, Grad Sch Sci, Ctr Nucl Study, Bunkyo Ku, Tokyo 1130033, Japan. High Energy Accelerator Res Org, Tsukuba, Ibaraki 3050801, Japan. Nagasaki Inst Appl Sci, Nagasaki 8510193, Japan. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Univ Tokyo, Grad Sch Sci, Dept Phys, Bunkyo Ku, Tokyo 1130033, Japan. Waseda Univ, Adv Res Inst Sci & Engn, Shinjuku Ku, Tokyo 1698555, Japan. RP Oyama, K (reprint author), Univ Tokyo, Grad Sch Sci, Ctr Nucl Study, Bunkyo Ku, 7-3-1 Hongo, Tokyo 1130033, Japan. RI Hayano, Ryugo/F-7889-2012; HAMAGAKI, HIDEKI/G-4899-2014 OI Hayano, Ryugo/0000-0002-1214-7806; NR 4 TC 2 Z9 2 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 OCT 11 PY 2000 VL 453 IS 1-2 BP 382 EP 385 DI 10.1016/S0168-9002(00)00661-6 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 366PA UT WOS:000090012700063 ER PT J AU Lange, JS Adler, C Barger, J Demello, M Flierl, D Landgraf, J LeVine, MJ Ljubicic, A Nelson, J Roehrich, D Schambach, JJ Schmischke, D Schulz, MW Stock, R Struck, C Yepes, P AF Lange, JS Adler, C Barger, J Demello, M Flierl, D Landgraf, J LeVine, MJ Ljubicic, A Nelson, J Roehrich, D Schambach, JJ Schmischke, D Schulz, MW Stock, R Struck, C Yepes, P TI The STAR level-3 trigger system SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 7th International Conference on Instrumentation for Colliding Beam Physics (INSTR99) CY NOV 15-19, 1999 CL HAMAMATSU, JAPAN SP Japanese Minist Educ Sci Sports & Culture, Inoue Fdn Sci, Res Fdn Opt Sci & Technol, Fdn High Energy Accelerator Sci DE trigger; data acquisition; nucleus-nucleus collisions; proton-proton collisions AB The STAR level-3 trigger is a MYRINET interconnected ALPHA processor farm, performing online tracking of N-track greater than or equal to 8000 particles (N-point less than or equal to 45 per track) with a design input rate of R = 100 Hz. A large-scale prototype system was tested in 12/99 with laser and cosmic particle events, (C) 2000 Published by Elsevier Science B.V. All rights reserved. C1 Univ Frankfurt, D-60486 Frankfurt, Germany. Rice Univ, Houston, TX 77251 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. Univ Birmingham, Birmingham B15 2TT, W Midlands, England. Univ Bergen, N-5007 Bergen, Norway. Univ Texas, Austin, TX 78712 USA. Univ Heidelberg, D-69120 Heidelberg, Germany. RP Lange, JS (reprint author), Univ Frankfurt, August Euler Str 6, D-60486 Frankfurt, Germany. NR 7 TC 11 Z9 11 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 OCT 11 PY 2000 VL 453 IS 1-2 BP 397 EP 404 DI 10.1016/S0168-9002(00)00664-1 PG 8 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 366PA UT WOS:000090012700066 ER PT J AU Yeh, GP AF Yeh, GP TI Computing farms SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 7th International Conference on Instrumentation for Colliding Beam Physics (INSTR99) CY NOV 15-19, 1999 CL HAMAMATSU, JAPAN SP Japanese Minist Educ Sci Sports & Culture, Inoue Fdn Sci, Res Fdn Opt Sci & Technol, Fdn High Energy Accelerator Sci DE computing; PC; farm; Linux; cluster; Beowulf AB High-energy physics, nuclear physics, space sciences, and many other fields have large challenges in computing. In recent years, PCs have achieved performance comparable to the high-end UNIX workstations, at a small fraction of the price. We review the development and broad applications of commodity PCs as the solution to CPU needs, and look forward to the important and exciting future of large-scale PC computing. (C) 2000 Published by Elsevier Science B.V. All rights reserved. C1 Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. Acad Sinica, Taipei 115, Taiwan. RP Yeh, GP (reprint author), Fermi Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. NR 6 TC 0 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 OCT 11 PY 2000 VL 453 IS 1-2 BP 417 EP 424 DI 10.1016/S0168-9002(00)00675-6 PG 8 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 366PA UT WOS:000090012700069 ER PT J AU Akerlof, C Balsano, R Barthelmy, S Bloch, J Butterworth, P Casperson, D Cline, T Fletcher, S Gisler, G Hills, J Kehoe, R Lee, B Marshall, S McKay, T Pawl, A Priedhorsky, W Seldomridge, N Szymanski, J Wren, J AF Akerlof, C Balsano, R Barthelmy, S Bloch, J Butterworth, P Casperson, D Cline, T Fletcher, S Gisler, G Hills, J Kehoe, R Lee, B Marshall, S McKay, T Pawl, A Priedhorsky, W Seldomridge, N Szymanski, J Wren, J TI Rapid optical follow-up observations of SGR events with ROTSE-I SO ASTROPHYSICAL JOURNAL LA English DT Article DE gamma rays : bursts; gamma rays : observations; pulsars : individual (SGR 1900+14; SGR 1806-20) ID GAMMA-RAY BURST; MAGNETIZED NEUTRON-STARS; HIGH-ENERGY TRANSIENT; REPEATER SGR1900+14; PULSAR; IDENTIFICATION; EXTINCTION; SGR1806-20; COINCIDENT; OUTBURST AB In order to observe nearly simultaneous emission from gamma-ray bursts (GRBs), the Robotic Optical Transient Search Experiment (ROTSE) receives triggers via the GRB Coordinates Network (GCN). Since beginning operations in 1998 March, ROTSE has also taken useful data for 10 SGR events: eight from SGR 1900 + 14 and two from SGR 1806-20. We have searched for new or variable sources in the error regions of these SGRs, and no optical counterparts were observed. Limits are in the range m(ROTSE) approximate to 12.5-15.5 during the period 20 s to 1 hr after the observed SGR events. C1 Univ Michigan, Ann Arbor, MI 48109 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Akerlof, C (reprint author), Univ Michigan, Ann Arbor, MI 48109 USA. RI Barthelmy, Scott/D-2943-2012; McKay, Timothy/C-1501-2009; OI McKay, Timothy/0000-0001-9036-6150; Priedhorsky, William/0000-0003-0295-9138 NR 41 TC 10 Z9 10 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD OCT 10 PY 2000 VL 542 IS 1 BP 251 EP 256 DI 10.1086/309535 PN 1 PG 6 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 365ME UT WOS:000089954400025 ER PT J AU Alcock, C Allsman, R Alves, DR Axelrod, T Becker, A Bennett, D Clement, C Cook, KH Drake, A Freeman, K Geha, M Griest, K Kovacs, G Kurtz, DW Lehner, M Marshall, S Minniti, D Nelson, C Peterson, B Popowski, P Pratt, M Quinn, P Rodgers, A Rowe, J Stubbs, C Sutherland, W Tomaney, A Vandehei, T Welch, DL AF Alcock, C Allsman, R Alves, DR Axelrod, T Becker, A Bennett, D Clement, C Cook, KH Drake, A Freeman, K Geha, M Griest, K Kovacs, G Kurtz, DW Lehner, M Marshall, S Minniti, D Nelson, C Peterson, B Popowski, P Pratt, M Quinn, P Rodgers, A Rowe, J Stubbs, C Sutherland, W Tomaney, A Vandehei, T Welch, DL TI The MACHO project Large Magellanic Cloud variable-star inventory. IX. Frequency analysis of the first-overtone RR Lyrae stars and the indication for nonradial pulsations SO ASTROPHYSICAL JOURNAL LA English DT Article DE globular clusters : general; Magellanic Clouds; stars : horizontal-branch; stars : oscillations; stars : variables : other ID GLOBULAR-CLUSTERS; PERIOD CHANGES; PHOTOMETRY; MODES; AGE; M15 AB More than 1300 variables classified provisionally as first-overtone RR Lyrae pulsators in the MACHO variable-star database of the Large Magellanic Cloud (LMC) have been subjected to standard frequency analysis. Based on the remnant power in the prewhitened spectra, we found 70% of the total population to be monoperiodic. The remaining 30% (411 stars) are classified as one of nine types according to their frequency spectra. Several types of RR Lyrae pulsational behavior are clearly identified here for the first time. Together with the earlier discovered double-mode (fundamental and first-overtone) variables, this study increased the number of known double-mode stars in the LMC to 181. During the total 6.5 yr time span of the data, 10% of the stars showed strong period changes. The size, and in general also the patterns of the period changes, exclude a simple evolutionary explanation. We also discovered two additional types of multifrequency pulsators with low occurrence rates of 2% for each. In the first type, there remains one closely spaced component after prewhitening by the main pulsation frequency. In the second type, the number of remnant components is two; they are also closely spaced, and are symmetric in their frequency spacing relative to the central component. This latter type of variables are associated with their relatives among the fundamental pulsators, known as Blazhko variables. Their high frequency (approximate to 20%) among the fundamental-mode variables versus the low occurrence rate of their first-overtone counterparts makes it more difficult to explain the Blazhko phenomenon by any theory depending mainly on the role of aspect angle or magnetic field. None of the current theoretical models are able to explain the observed close frequency components without invoking nonradial pulsation components in these stars. C1 Lawrence Livermore Natl Lab, Inst Geophys & Planetary Phys, Livermore, CA 94550 USA. Australian Natl Univ, Mt Stromlo & Siding Spring Observ, Weston, ACT 0200, Australia. Space Telescope Sci Inst, Baltimore, MD 21218 USA. Univ Washington, Dept Astron, Seattle, WA 98195 USA. Univ Notre Dame, Dept Phys, Notre Dame, IN 46556 USA. Univ Toronto, Dept Astron, Toronto, ON M5S 3H8, Canada. Univ Calif San Diego, Dept Phys, La Jolla, CA 92093 USA. Konkoly Observ Budapest, H-1525 Budapest, Hungary. Univ Cape Town, Dept Astron, ZA-7701 Rondebosch, South Africa. Univ Sheffield, Dept Phys, Sheffield S3 7RH, S Yorkshire, England. Catholic Univ, Dept Astron, Santiago, Chile. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. European So Observ, D-85748 Garching, Germany. Univ Oxford, Dept Phys, Oxford OX1 3RH, England. McMaster Univ, Dept Phys & Astron, Hamilton, ON L82 4M1, Canada. RP Alcock, C (reprint author), Lawrence Livermore Natl Lab, Inst Geophys & Planetary Phys, Livermore, CA 94550 USA. RI Stubbs, Christopher/C-2829-2012; Quinn, Peter/B-3638-2013 OI Stubbs, Christopher/0000-0003-0347-1724; NR 34 TC 72 Z9 73 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD OCT 10 PY 2000 VL 542 IS 1 BP 257 EP 280 DI 10.1086/309530 PN 1 PG 24 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 365ME UT WOS:000089954400026 ER PT J AU Alcock, C Allsman, RA Alves, DR Axelrod, TS Becker, AC Bennett, DP Cook, KH Dalal, N Drake, AJ Freeman, KC Geha, M Griest, K Lehner, MJ Marshall, SL Minniti, D Nelson, CA Peterson, BA Popowski, P Pratt, MR Quinn, PJ Stubbs, CW Sutherland, W Tomaney, AB Vandehei, T Welch, D AF Alcock, C Allsman, RA Alves, DR Axelrod, TS Becker, AC Bennett, DP Cook, KH Dalal, N Drake, AJ Freeman, KC Geha, M Griest, K Lehner, MJ Marshall, SL Minniti, D Nelson, CA Peterson, BA Popowski, P Pratt, MR Quinn, PJ Stubbs, CW Sutherland, W Tomaney, AB Vandehei, T Welch, D TI The MACHO project: Microlensing results from 5.7 years of Large Magellanic Cloud observations SO ASTROPHYSICAL JOURNAL LA English DT Article DE dark matter; Galaxy : halo; Galaxy : structure; gravitational lensing; stars : low-mass, brown dwarfs; white dwarfs ID GRAVITATIONAL LENSING EXPERIMENT; GALACTIC DARK HALO; OPTICAL DEPTH; WHITE-DWARFS; EVENT; OBJECTS; MATTER; COLLABORATION; PHOTOMETRY; DATABASE AB We report on our search for microlensing toward the Large Magellanic Cloud (LMC). Analysis of 5.7 yr of photometry on 11.9 million stars in the LMC reveals 13-17 microlensing events. A detailed treatment of our detection efficiency shows that this is significantly more than the similar to2-4 events expected from lensing by known stellar populations. The timescales ((t) over cap) of the events range from 34 to 230 days. We estimate the microlensing optical depth toward the LMC from events with 2 < <(t)over cap> < 400 days to be (400)(2) = 1.2(-0.3)(+0.4) x 10(-7), with an additional 20% to 30% of systematic error. The spatial distribution of events is mildly inconsistent with LMC/LMC disk self-lensing, but is consistent with an extended lens distribution such as a Milky Way or LMC halo. Interpreted in the context of a Galactic dark matter halo, consisting partially of compact objects, a maximum-likelihood analysis gives a MACHO halo fraction of 20% for a typical halo model with a 95% confidence interval of 8%-50%. A 100% MACHO halo is ruled out at the 95% confidence level for all except our most extreme halo model. Interpreted as a Galactic halo population, the most likely MACHO mass is between 0.15 and 0.9 Mo, depending on the halo model, and the total mass in MACHOs out to 50 kpc is found to be 9(-3)(+4) x 10(10) M., independent of the halo model. These results are marginally consistent with our previous results, but are lower by about a factor of 2. This is mostly due to Poisson noise, because with 3.4 times more exposure and increased sensitivity to long-timescale events, we did not find the expected factor of similar to4 more events. In addition to a larger data set, this work also includes an improved efficiency determination, improved likelihood analysis, and more thorough testing of systematic errors, especially with respect to the treatment of potential backgrounds to microlensing. We note that an important source of background are supernovae (SNe) in galaxies behind the LMC. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Calif Berkeley, Ctr Particle Astrophys, Berkeley, CA 94720 USA. Australian Natl Univ, Supercomp Facil, Canberra, ACT 0200, Australia. Space Telescope Sci Inst, Baltimore, MD 21218 USA. Res Sch Astron & Astrophys, Weston Creek, ACT 2611, Australia. Univ Washington, Dept Astron, Seattle, WA 98195 USA. Univ Washington, Dept Phys, Seattle, WA 98195 USA. Univ Notre Dame, Dept Phys, Notre Dame, IN 46556 USA. Univ Calif San Diego, Dept Phys, La Jolla, CA 92093 USA. Univ Sheffield, Dept Phys, Sheffield S3 7RH, S Yorkshire, England. Pontificia Univ Catolica Chile, Dept Astron, Santiago 22, Chile. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. European So Observ, D-85748 Garching, Germany. Univ Oxford, Dept Phys, Oxford OX1 3RH, England. McMaster Univ, Hamilton, ON L8S 4M1, Canada. RP Alcock, C (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RI Quinn, Peter/B-3638-2013; Stubbs, Christopher/C-2829-2012; OI Stubbs, Christopher/0000-0003-0347-1724; Lehner, Matthew/0000-0003-4077-0985 NR 61 TC 564 Z9 570 U1 2 U2 12 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD OCT 10 PY 2000 VL 542 IS 1 BP 281 EP 307 DI 10.1086/309512 PN 1 PG 27 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 365ME UT WOS:000089954400027 ER PT J AU Borozdin, KN Priedhorsky, WC AF Borozdin, KN Priedhorsky, WC TI On the integrated spectrum of the X-ray binaries and the origin of soft X-ray emission from the bulge of M31 SO ASTROPHYSICAL JOURNAL LA English DT Article DE binaries : close; galaxies : individual (M31); galaxies : ISM; X-rays : galaxies; X-rays : stars ID EARLY-TYPE GALAXIES; MECHANISMS AB Using ROSAT PSPC data, we have performed several tests aimed at understanding the origin of the soft X-ray spectral component detected from the bulge of M31. We find that a significant soft component in the spectrum of the bulge is spatially correlated with the unresolved X-ray emission near the core of M31, which is probably a hot interstellar medium or perhaps a population of multiple faint sources. For the first time, we extracted the spectrum of this unresolved emission, by removing point sources dominating the integral spectrum of the bulge, and found it to be responsible for most of the soft excess. A soft spectral component is not at all needed to fit the point-source spectrum that remains after subtracting the unresolved emission. Tl-le integral spectra of bright point sources, both inside and outside of the M31 bulge, can be fitted with a single power law in the ROSAT band. Our analysis rules out the previous suggestion that all bulge emission in M31 may be generated by low-mass X-ray binaries (Irwin & Bregman). C1 Univ Calif Los Alamos Natl Lab, NIS Div, Los Alamos, NM 87545 USA. RP Borozdin, KN (reprint author), Univ Calif Los Alamos Natl Lab, NIS Div, POB 1663, Los Alamos, NM 87545 USA. NR 18 TC 9 Z9 9 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD OCT 10 PY 2000 VL 542 IS 1 BP L13 EP L16 DI 10.1086/312913 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 365MF UT WOS:000089954500004 ER PT J AU Guzik, JA Kaye, AB Bradley, PA Cox, AN Neuforge, C AF Guzik, JA Kaye, AB Bradley, PA Cox, AN Neuforge, C TI Driving the gravity-mode pulsations in gamma Doradus variables SO ASTROPHYSICAL JOURNAL LA English DT Article DE stars : oscillations; stars : variables : other ID STELLAR PULSATIONS; STARS AB The gamma Doradus stars are a newly discovered class of gravity-mode pulsators that lie just at or beyond the red edge of the delta Scuti instability strip. We present the results of calculations that the predict pulsation instability of high-order g-modes with periods between 0.4 and 3 days, as observed in these stars. The pulsations are driven by the modulation of the radiative flux by convection at the base of a deep envelope convection zone. Pulsation instability is predicted only for models with temperatures at the convection zone base between similar to 200,000 and similar to 480,000 K. The estimated shear dissipation that is due to turbulent viscosity within the convection zone or in an overshoot region below the convection zone can be comparable to or even exceed the predicted driving and is likely to reduce the number of unstable modes or possibly quench the instability. Additional refinements in the pulsation modeling are required to determine the outcome. At least one gamma Doradus star has been observed that also pulsates in delta Scuti-type p-modes, and others have been identified as chemically peculiar. Since our calculated driving region is relatively deep, gamma Doradus pulsations are not necessarily incompatible with surface abundance peculiarities or with delta Scuti p-mode pulsations driven by the H and He ionization K-effect. Such stars will provide useful observational constraints on the proposed gamma Doradus pulsation mechanism. C1 Los Alamos Natl Lab, Div Appl Phys, Los Alamos, NM 87545 USA. RP Guzik, JA (reprint author), Los Alamos Natl Lab, Div Appl Phys, X-2,Mail Stop B220, Los Alamos, NM 87545 USA. EM joy@lanl.gov; kaye@lanl.gov; pbradley@lanl.gov; anc@lanl.gov; neuforge@lanl.gov NR 19 TC 120 Z9 120 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD OCT 10 PY 2000 VL 542 IS 1 BP L57 EP L60 DI 10.1086/312908 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 365MF UT WOS:000089954500015 ER PT J AU Cox, EH McLendon, GL Morel, FMM Lane, TW Prince, RC Pickering, IJ George, GN AF Cox, EH McLendon, GL Morel, FMM Lane, TW Prince, RC Pickering, IJ George, GN TI The active site structure of Thalassiosira weissflogii carbonic anhydrase 1 SO BIOCHEMISTRY LA English DT Article ID ABSORPTION FINE-STRUCTURE; CHLAMYDOMONAS-REINHARDTII; SEQUENCE AB X-ray absorption spectroscopy at the Zn K-edge indicates that the active site of the marine diatom Thalassiosira weissflogii carbonic anhydrase is strikingly similar to that of mammalian alpha-carbonic anhydrase enzymes. The zinc has three histidine ligands and a single water at 1.98 Angstrom. This is quite different from the beta-carbonic anhydrases of higher plants in which zinc is coordinated by two cysteine thiolates, one histidine, and a water molecule. The diatom carbonic anhydrase shows no significant sequence similarity with other carbonic anhydrases and may represent an example of convergent evolution at the molecular level. C1 Stanford Univ, Stanford Synchrotron Radiat Lab, SLAC, Stanford, CA 94309 USA. Princeton Univ, Dept Chem, Ctr Environm Bioinorgan Chem, Princeton, NJ 08544 USA. Princeton Univ, Dept Geosci, Princeton, NJ 08544 USA. ExxonMobil Res & Engn Co, Annandale, NJ 08801 USA. RP Morel, FMM (reprint author), Stanford Univ, Stanford Synchrotron Radiat Lab, SLAC, POB 20450,MS 69, Stanford, CA 94309 USA. RI Morel, Francois/A-8107-2008; George, Graham/E-3290-2013; Cox, Elizabeth/O-9044-2015; Pickering, Ingrid/A-4547-2013; OI Cox, Elizabeth/0000-0003-0467-6609; Lane, Todd/0000-0002-5816-2649; Pickering, Ingrid/0000-0002-0936-2994 NR 21 TC 84 Z9 88 U1 0 U2 7 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0006-2960 J9 BIOCHEMISTRY-US JI Biochemistry PD OCT 10 PY 2000 VL 39 IS 40 BP 12128 EP 12130 DI 10.1021/bi001416s PG 3 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 363CB UT WOS:000089815700004 PM 11015190 ER PT J AU Buchko, GW Hess, NJ Bandaru, V Wallace, SS Kennedy, MA AF Buchko, GW Hess, NJ Bandaru, V Wallace, SS Kennedy, MA TI Spectroscopic studies of zinc(II)- and cobalt(II)-associated Escherichia coli formamidopyrimidine-DNA glycosylase: Extended X-ray absorption fine structure evidence for a metal-binding domain SO BIOCHEMISTRY LA English DT Article ID NUCLEOTIDE EXCISION-REPAIR; APURINIC APYRIMIDINIC SITES; FPG PROTEIN; OGG1 GENE; SACCHAROMYCES-CEREVISIAE; SUBSTRATE-SPECIFICITY; IMPROVED SENSITIVITY; IONIZING-RADIATION; SYNTHESIS PAST; HUMAN HOMOLOG AB Formamidopyrimidine-DNA glycosylase (Fpg) is a 30.2 kDa protein that plays an important role in the base excision repair of oxidatively damaged DNA in Escherichia coli. Sequence analysis and genetic evidence suggest that zinc is associated with a C4-type motif, C-244-X-2-C-247-X-16-C-264-X-2-C-267, located at the C-terminus of the protein. The zinc-associated motif has been shown to be essential for damaged DNA recognition. Extended X-ray absorption fine structure (EXAFS) spectra collected on the zinc-associated protein (ZnFpg) in the lyophilized state and in 10% frozen aqueous glycerol solution show directly that the metal is coordinated to the sulfur atom of four cysteine residues. The average Zn-S bond length is 2.33 +/- 0.01 and 2.34 +/- 0.01 Angstrom, respectively, in the lyophilized state and in 10% frozen aqueous glycerol solution. Fpg was also expressed in minimal medium supplemented with cobalt nitrate to yield a blue-colored protein that was primarily cobalt-associated (CoFpg). The profiles of the circular dichroism spectra for CoFpg and ZnFpg are identical, suggesting that the substitution of Co2+ for Zn2+ does not alter the structure of Fpg. A similar conclusion is reached upon the analysis of two-dimensional N-15/H-1 HSQC spectra of uniformly N-15-labeled samples of ZnFpg and CoFpg; the spectra are similar and display features characteristic of a structured protein. Biochemical assays with a 54 nt DNA oligomer containing 7,8-dihydro-8-oxoguanine at a specific location show that CoFpg and ZnFpg are equally active at cleaving the DNA at the site of the oxidized guanine. EXAFS spectra of CoFpg indicate that the cobalt is coordinated to the sulfur atom of four cysteine residues with an average Co-S bond length of 2.28 +/- 0.01 and 2.29 +/- 0.01 Angstrom, respectively, in the lyophilized state and in 10% frozen aqueous glycerol solution. The structural similarity between CoFpg and ZnFpg suggests that it is biologically relevant to use the paramagnetic properties of Co2+ as a structural probe. C1 Pacific NW Natl Lab, Environm Mol Sci Lab & Biogeochem Resources, Richland, WA 99352 USA. Univ Vermont, Dept Microbiol & Mol Genet, Burlington, VT 05405 USA. RP Kennedy, MA (reprint author), Pacific NW Natl Lab, Environm Mol Sci Lab & Biogeochem Resources, Richland, WA 99352 USA. RI Buchko, Garry/G-6173-2015; OI Buchko, Garry/0000-0002-3639-1061; Wallace, Susan S./0000-0002-3906-0321; Hess, Nancy/0000-0002-8930-9500 NR 71 TC 24 Z9 24 U1 0 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0006-2960 J9 BIOCHEMISTRY-US JI Biochemistry PD OCT 10 PY 2000 VL 39 IS 40 BP 12441 EP 12449 DI 10.1021/bi001377k PG 9 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 363CB UT WOS:000089815700039 PM 11015225 ER PT J AU Warpinski, NR AF Warpinski, NR TI Analytic crack solutions for tilt fields around hydraulic fractures SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH LA English DT Article AB The recent development of downhole tiltmeter arrays for monitoring hydraulic fractures has provided new information on fracture growth and geometry. These downhole arrays offer the significant advantages of being close to the fracture (large signal) and being unaffected by the free surface. As with surface tiltmeter data, analysis of these measurements requires the inversion of a crack or dislocation model. To supplement the dislocation models of Davis [1983], Okada [1992], and others, this work has extended several elastic crack solutions to provide tilt calculations. The solutions include constant-pressure two-dimensional (2-D), penny-shaped, and 3-D-elliptic cracks and a 2-D-variable-pressure crack. Equations are developed for an arbitrary inclined fracture in an infinite elastic space. Effects of fracture height, fracture length, fracture dip, fracture azimuth, fracture width, and monitoring distance on the tilt distribution are given, as well as comparisons with the dislocation model. The results show that the tilt measurements are very sensitive to the fracture dimensions but also that it is difficult to separate the competing effects of the various parameters. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Warpinski, NR (reprint author), Sandia Natl Labs, POB 5800,MS 0750, Albuquerque, NM 87185 USA. EM nrwarpi@sandia.gov NR 23 TC 5 Z9 5 U1 1 U2 4 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-9313 EI 2169-9356 J9 J GEOPHYS RES-SOL EA JI J. Geophys. Res.-Solid Earth PD OCT 10 PY 2000 VL 105 IS B10 BP 23463 EP 23478 DI 10.1029/2000JB900211 PG 16 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 364MG UT WOS:000089895700009 ER PT J AU Huser, T Yan, M Rothberg, LJ AF Huser, T Yan, M Rothberg, LJ TI Single chain spectroscopy of conformational dependence of conjugated polymer photophysics SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article ID LIGHT-HARVESTING COMPLEXES; INTERCHAIN INTERACTIONS; MOLECULES; FLUORESCENCE; DYNAMICS; LUMINESCENCE; ELASTICITY; PROTEIN AB Single molecule confocal fluorescence microscopy was used to perform photoluminescence spectroscopy on single, isolated molecules of the conjugated polymer poly[2-methoxy,5-(2'-ethylhexyloxy)-p-phenylene-vinylene] (MEH-PPV). We show that the fluorescence from single chains of this electroluminescent polymer depends strongly on chain conformation. The time evolution of the spectra, emission intensity, and polarization all provide direct evidence that memory of the chain conformation in solution is retained after solvent evaporation. Chains cast from toluene solution are highly folded and show memory of the excitation polarization. Exciton funneling to highly aggregated low energy regions causes the chain to mimic the photophysical behavior of a single chromophore. Chains cast from chloroform, however, behave as multichromophore systems, and no sudden discrete spectral or intensity jumps are observed. These also exhibit different spectroscopy from the folded chromophores. C1 Univ Calif Lawrence Livermore Natl Lab, Dept Chem & Mat Sci, Livermore, CA 94551 USA. Univ Rochester, Ctr Photoinduced Charge Transfer, Rochester, NY 14627 USA. RP Huser, T (reprint author), Univ Calif Lawrence Livermore Natl Lab, Dept Chem & Mat Sci, M-S L-250, Livermore, CA 94551 USA. RI Huser, Thomas/H-1195-2012 OI Huser, Thomas/0000-0003-2348-7416 NR 26 TC 241 Z9 243 U1 4 U2 44 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 OCT 10 PY 2000 VL 97 IS 21 BP 11187 EP 11191 DI 10.1073/pnas.97.21.11187 PG 5 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 363GA UT WOS:000089825700015 PM 11027327 ER PT J AU Chang, CM Wei, CM Chen, SP AF Chang, CM Wei, CM Chen, SP TI Structural and dynamical behavior of Al trimer on Al(111)surface SO SURFACE SCIENCE LA English DT Article DE aluminum; density functional calculations; molecular dynamics; surface diffusion ID INITIO MOLECULAR-DYNAMICS; TOTAL-ENERGY CALCULATIONS; WAVE BASIS-SET; SURFACE-DIFFUSION; ELECTRON-GAS; IR SURFACES; CLUSTERS; METALS; TRANSITION; SIMULATION AB Trimer is the smallest cluster that can have a one-dimensional or two-dimensional structure on surfaces, and it can diffuse and transform between these structures. Using first-principles density-functional theory (DFT) calculations, the structural and dynamical behaviors of Al trimer on Al(111) surface have been studied in detail. Al trimer on Al(111) surface has three different kinds of structure conformations (groups with similar configurations): close-packed (compact) triangular trimers, non-compact triangular trimers, and linear trimers. The close-packed triangular trimers are more stable than the non-compact triangular trimers and the linear trimers, while most of the non-compact triangular trimers are as stable as the linear trimers. For the dynamics of Al trimer on Al(111) surface, there are three different kinds of diffusion mechanisms: (1) concerted translations and rotation of compact triangular trimers (the highest energy barrier by DFT calculation, E-d=0.24 eV); (2) back-and-forth transformation between compact triangular trimers and linear trimers (E-d=0.21 eV); and (3) translation of linear trimers (E-d=0.28 eV). Among these different mechanisms with similar height of diffusion barriers, the concerted translations of the compact triangular trimers have the longest displacement of the center of mass in the least steps. Therefore, we expect the long-range diffusion of Al trimer on Al(111) surface is dominated by the concerted motion process of the compact triangular trimers. The concerted translations and concerted rotations of Al trimer on Al(111) surface have also been observed in the molecular dynamics simulations using the embedded atom method. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Natl Ctr High Performance Comp, Hsinchu 30043, Taiwan. Acad Sinica, Inst Phys, Taipei 11529, Taiwan. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Chang, CM (reprint author), Natl Ctr High Performance Comp, Hsinchu 30043, Taiwan. EM c00jim00@nchc.gov.tw RI Wei, Ching-Ming/F-7931-2012 NR 28 TC 11 Z9 11 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 EI 1879-2758 J9 SURF SCI JI Surf. Sci. PD OCT 10 PY 2000 VL 465 IS 1-2 BP 65 EP 75 DI 10.1016/S0039-6028(00)00663-4 PG 11 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA 368PV UT WOS:000090127400009 ER PT J AU Markovic, NM Lucas, CA Climent, V Stamenkovic, V Ross, PN AF Markovic, NM Lucas, CA Climent, V Stamenkovic, V Ross, PN TI Surface electrochemistry on an epitaxial palladium film on Pt(111): surface microstructure and hydrogen electrode kinetics SO SURFACE SCIENCE LA English DT Article DE catalysis; electrochemical methods; epitaxy; palladium; platinum; solid-liquid interfaces; surface chemical reaction; surface structure, morphology, roughness, and topography; X-ray scattering, diffraction, and reflection ID ULTRATHIN PD FILMS; IRREVERSIBLY ADSORBED PALLADIUM; CO CHEMISORPTION PROPERTIES; SINGLE-CRYSTAL SURFACES; AU(111) ELECTRODE; METAL-SURFACES; ADSORPTION; OVERLAYERS; INTERFACE; BEHAVIOR AB The surface electrochemistry of adsorbed hydrogen (H-upd) and the kinetics of the hydrogen evolution/oxidation reactions (HER/HOR) have been studied on an epitaxial Pd layer on Pt(111) in 0.05 M H2SO4 in a temperature range of 278-333 K. The morphology and stability of the Pd film during the electrochemical reactions was investigated by means of in situ surface X-ray scattering (SXS). The SXS results show that Pd is deposited onto Pt(111) as a uniform epitaxial metallic layer having the Pt lattice constant, that is, pseudomorphic growth. Due to the strong interaction between the Pd film and adsorbed hydrogen (H-upd), it appears that some of the H-upd on Pt(111)-Pd may be in the subsurface state. This change in the energetics of the H-upd state plays a dominant role in the kinetics of the HER/HOP. The kinetics of the HER/HOR were studied on Pt(111) and Pt(111)-Pd by utilizing the rotating disk electrode method. We find significant differences in the electrochemical properties between these two systems, the rate of reaction being much faster on the Pt(111)-Pd electrode. We propose that the physical model that appears to rationalize the results for the HER/HOR at low anodic overpotentials on Pt(111)-Pd is one which follows application of the Langmuir (ideal) adsorption isotherm for the reaction intermediate (H-opd) and the Volmer-Heyrowsky sequence, the Heyrowsky step being the rds. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Univ Liverpool, Dept Phys, Oliver Lodge Lab, Liverpool L69 7ZE, Merseyside, England. Univ Alicante, Dept Quim Fis, E-03080 Alicante, Spain. RP Markovic, NM (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RI Climent, Victor/F-6491-2011; OI Climent, Victor/0000-0002-2033-5284; Lucas, Christopher/0000-0001-5743-3868 NR 31 TC 68 Z9 69 U1 2 U2 43 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 J9 SURF SCI JI Surf. Sci. PD OCT 10 PY 2000 VL 465 IS 1-2 BP 103 EP 114 DI 10.1016/S0039-6028(00)00674-9 PG 12 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA 368PV UT WOS:000090127400014 ER PT J AU Niu, C Shepherd, K Martini, D Tong, J Kelber, JA Jennison, DR Bogicevic, A AF Niu, C Shepherd, K Martini, D Tong, J Kelber, JA Jennison, DR Bogicevic, A TI Cu interactions with alpha-Al2O3(0001): effects of surface hydroxyl groups versus dehydroxylation by Ar-ion sputtering SO SURFACE SCIENCE LA English DT Article DE ab initio quantum chemical methods and calculations; aluminium oxide; chemisorption; copper; sputter deposition; wetting; X-ray photoelectron spectroscopy ID ELECTRONIC-STRUCTURE; AL2O3(0001) SURFACE; MOLECULAR-DYNAMICS; COPPER CLUSTERS; FILM GROWTH; WATER-VAPOR; AL2O3; XPS; SPECTROSCOPY; OXIDE AB X-ray photoelectron spectroscopy studies and first principles calculations compare Cu adsorption on heavily hydroxylated alpha -Al2O3(0001) with dehydroxylated surfaces produced by Ar+ sputtering followed by annealing in O-2. Annealing a cleaned sapphire sample with an O-2 partial pressure of similar to 5 x 10(-6) Torr removes most contaminants, but leaves a surface with similar to0.4 ML (ML: monolayer) carbon and similar to0.4 ML OH. Subsequent light (6 min) Ar-ion sputtering at 1 keV reduces the carbon to undetectable levels but does not dehydroxylate the surface. Further sputtering at higher Ar-ion excitation energies (>2 keV) partially dehydroxylates the surface, whereas 5 keV Ar-ion sputtering creates oxygen vacancies in the surface region. Further annealing in O-2 repairs the oxygen vacancies in the top layers, but those beneath the surface remain. Deposition of Cu on the hydroxylated surface at 300 K results in a maximum copper(I) coverage of similar to0.35 ML, in agreement with theoretical predictions. Maximum copper(I) coverage at 300 K decreases with decreasing surface hydroxylation. Exposure of a partially dehydroxylated sapphire(0001) surface to either 2 Torr H2O vapor or air results in recovery of surface hydroxylation, which in turn increases the maximum copper(I) coverage. These results demonstrate that the hydroxyl surface coverage critically affects the ability of Cu to 'wet' sapphire(0001) at 300 K. In addition, first principles density functional calculations show that while an ad-OH species stabilizes copper(I) at room temperature, any nearby in-surface OH does the opposite. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ N Texas, Dept Chem, Denton, TX 76203 USA. Sandia Natl Labs, Surface & Interface Sci Dept, Albuquerque, NM 87185 USA. RP Univ N Texas, Dept Chem, Denton, TX 76203 USA. EM kelber@unt.edu NR 50 TC 72 Z9 72 U1 2 U2 28 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 EI 1879-2758 J9 SURF SCI JI Surf. Sci. PD OCT 10 PY 2000 VL 465 IS 1-2 BP 163 EP 176 DI 10.1016/S0039-6028(00)00728-7 PG 14 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA 368PV UT WOS:000090127400020 ER PT J AU LaForge, KS Shick, V Spangler, R Proudnikov, D Yuferov, V Lysov, Y Mirzabekov, A Kreek, MJ AF LaForge, KS Shick, V Spangler, R Proudnikov, D Yuferov, V Lysov, Y Mirzabekov, A Kreek, MJ TI Detection of single nucleotide polymorphisms of the human mu opioid receptor gene by hybridization or single nucleotide extension on custom oligonucleotide gelpad microchips: Potential in studies of addiction SO AMERICAN JOURNAL OF MEDICAL GENETICS LA English DT Article DE SNP; polymorphism; mu opioid receptor; addiction; microchips ID CONTROLLING MORPHINE PREFERENCE; POLYMERASE CHAIN-REACTION; POPULATION-BASED SAMPLE; MESSENGER-RNA LEVELS; ALCOHOL DEPENDENCE; INDUCED ANALGESIA; OPIATE RECEPTOR; FEMALE TWINS; FAMILIAL TRANSMISSION; CANDIDATE GENES AB The human mu opioid receptor (MOR) plays a central role in mediating the effects of opioids, both endogenous and exogenous. Epidemiological studies have shown that addiction in general, and especially opiate addiction, has a heritable component. Clinical and laboratory studies suggest that the MOR gene may contribute to the heritable component of vulnerability to develop opiate addiction. Naturally occurring single nucleotide polymorphisms (SNPs) have been identified in the MOR gene by conventional methods. Two coding region SNPs, the A118G; and C17T substitutions, occur at high allelic frequencies (10.5% and 6.6%, respectively, in our previous studies). These common SNPs cause amino acid changes in the receptor, and may have implications for differences in individual responses to opioids, as well as decreased or increased vulnerability to opiate addiction. The A118G substitution encodes a variant receptor with binding and signal transduction differences in response to beta-endorphin in cellular assays. Recent innovations in microchip technology offer new potential methods for SNP detection. We report here on the development of two separate approaches using custom oligonucleotide gelpad microarrays for detection of these two common SNPs of the MOR gene in human DNA samples. First, PCR-amplified genomic DNA samples were used to produce target sequences, which were labeled with fluorescent dye and hybridized to custom microchips. Oligonucleotides on these reusable microchips mere designed to query nucleotide substitutions at positions 17 and 118 of the MOR gene. Thirty-six human DNA samples were assayed both on these custom microchips and by conventional automated gel sequencing, with highly concordant identification of both heterozygous and homozygous substitutions. A second approach was developed for the C17T SNP utilizing single nucleotide extension on custom microchips. These custom gelpad microchips have potential for the rapid and inexpensive detection of specific SNPs for genetic and genomic studies. Am. J. Med. Genet. (Neuropsychiatr, Genet.) 96:604-615, 2000. (C) 2000 Wiley-Liss, Inc. C1 Rockefeller Univ, Lab Biol Addict Dis, New York, NY 10021 USA. Argonne Natl Lab, Biochip Technol Ctr, Argonne, IL 60439 USA. RP Rockefeller Univ, Lab Biol Addict Dis, Box 171,1230 York Ave, New York, NY 10021 USA. EM laforgk@rockvax.rockefeller.edu FU NCRR NIH HHS [MO1RR00102]; NIDA NIH HHS [DA00049, DA05130] NR 87 TC 36 Z9 38 U1 2 U2 9 PU WILEY-LISS PI HOBOKEN PA DIV JOHN WILEY & SONS INC, 111 RIVER ST, HOBOKEN, NJ 07030 USA SN 0148-7299 EI 1096-8628 J9 AM J MED GENET JI Am. J. Med. Genet. PD OCT 9 PY 2000 VL 96 IS 5 BP 604 EP 615 DI 10.1002/1096-8628(20001009)96:5<604::AID-AJMG5>3.0.CO;2-F PG 12 WC Genetics & Heredity SC Genetics & Heredity GA 360PX UT WOS:000089677400005 PM 11054767 ER PT J AU Matsuura, D Kanemitsu, Y Kushida, T White, CW Budai, JD Meldrum, A AF Matsuura, D Kanemitsu, Y Kushida, T White, CW Budai, JD Meldrum, A TI Optical characterization of CdS nanocrystals in Al2O3 matrices fabricated by ion-beam synthesis SO APPLIED PHYSICS LETTERS LA English DT Article ID GAAS NANOCRYSTALS; PHOTOLUMINESCENCE; IMPLANTATION; SIO2 AB We have studied optical properties of CdS nanocrystals formed by sequential Cd+ and S+ ion implantation into Al2O3 matrices. Two bands related to free excitons in the wurtzite CdS are clearly observed in the absorption spectrum at low temperatures. Efficient photoluminescence (PL) appears near the absorption edge. At high temperatures, the band edge PL band consists of two components. One is the free-exciton emission with a short lifetime (several hundreds of picoseconds), while the other is the bound exciton emission at shallow localized states with a long lifetime (several nanoseconds). The temperature dependence of the band gap energy has been determined for wurtzite CdS nanocrystals. Spectroscopic analysis shows that high-quality compound semiconductor nanocrystals are fabricated by the ion-beam synthesis technique. (C) 2000 American Institute of Physics. [S0003-6951(00)03241-1]. C1 Nara Inst Sci & Technol, Grad Sch Mat Sci, Nara 6300101, Japan. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Univ Alberta, Dept Phys, Edmonton, AB T6G 2J1, Canada. RP Kanemitsu, Y (reprint author), Nara Inst Sci & Technol, Grad Sch Mat Sci, Nara 6300101, Japan. RI Budai, John/R-9276-2016 OI Budai, John/0000-0002-7444-1306 NR 14 TC 49 Z9 49 U1 0 U2 7 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 OCT 9 PY 2000 VL 77 IS 15 BP 2289 EP 2291 DI 10.1063/1.1316777 PG 3 WC Physics, Applied SC Physics GA 359YE UT WOS:000089639000007 ER PT J AU Hakovirta, M Vuorinen, JE He, XM Nastasi, M Schwarz, RB AF Hakovirta, M Vuorinen, JE He, XM Nastasi, M Schwarz, RB TI Heat capacity of hydrogenated diamond-like carbon films SO APPLIED PHYSICS LETTERS LA English DT Article ID PLASMA AB We have used differential scanning calorimetry to measure the heat capacity of diamond-like carbon (DLC) film prepared by a plasma immersion ion processing method. The same calorimeter was used to measure the heat capacity of single crystal natural diamond and of high purity graphite. The amount of atomic hydrogen trapped in the DLC films was determined by elastic-recoil-detection spectrometry. The present data and literature values were used to deduce an expression for the specific heat that factors out the contribution from the sp(3)/sp(2) bonding and from the atomic hydrogen trapped in the carbon. The data shows that the hydrogen contribution to the specific heat of carbon is independent of the sp(3)/sp(2) bonding and amounts to about 0.63k(B) per hydrogen atom. We propose a simple method to determine the sp(3)/sp(2) bonding ratio in hydrogenated DLC films based on measuring the specific heat and the hydrogen content of the sample. (C) 2000 American Institute of Physics. [S0003-6951(00)05535-2]. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Tampere Univ Technol, Inst Mat Sci, FIN-33101 Tampere, Finland. RP Hakovirta, M (reprint author), CERN, CH-1211 Geneva 23, Switzerland. RI Vuorinen, Jyrki/G-4256-2014; OI Vuorinen, Jyrki/0000-0002-7537-1557 NR 10 TC 19 Z9 19 U1 0 U2 4 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 OCT 9 PY 2000 VL 77 IS 15 BP 2340 EP 2342 DI 10.1063/1.1290387 PG 3 WC Physics, Applied SC Physics GA 359YE UT WOS:000089639000024 ER PT J AU Ambrajei, AN Clendenin, JE Egorov, AY Mamaev, YA Maruyama, T Mulhollan, GA Subashiev, AV Yashin, YP Ustinov, VM Zhukov, AE AF Ambrajei, AN Clendenin, JE Egorov, AY Mamaev, YA Maruyama, T Mulhollan, GA Subashiev, AV Yashin, YP Ustinov, VM Zhukov, AE TI Spin-polarized electron transport and emission from strained superlattices SO APPLIED SURFACE SCIENCE LA English DT Article; Proceedings Paper CT 7th International Conference on the Formation of Semiconductor Interfaces (ICFSI-7) CY JUN 21-25, 1999 CL GOTHENBURG, SWEDEN SP Chalmers Univ Technol, Goteborg Univ, Royal Acad Sci, Nobel Inst Phys, Swedish Nat Sci Res Council, Swedish Res Council Engn Sci DE semiconductors; superlattices; electron states (localised); spin dynamics; electron emission spectroscopies AB Polarized electron emission from a series of new strained short-period AlInGaAs/AlGaAs superlattices (SLs) is investigated. The In layer content was chosen to give minimal conduction band offset with large strain splitting of the V-band. Simultaneous changing of Al content in both SL layers provides variation of the structure band gap. We demonstrate that tuning of the SL to the excitation energy can be achieved without loss of the electron polarization. The polarization of up to 84% was measured at room temperature. (C) 2000 Elsevier Science B.V. All rights reserved. C1 State Tech Univ, St Petersburg 195251, Russia. Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RAS, AF Ioffe Physicotech Inst, St Petersburg 194021, Russia. RP Mamaev, YA (reprint author), State Tech Univ, Polytechnicheskaya Str 29, St Petersburg 195251, Russia. RI Zhukov, Alexey/A-5523-2014; Ustinov, Viktor/J-3545-2013; Egorov, Anton/B-1267-2014 OI Zhukov, Alexey/0000-0002-4579-0718; Egorov, Anton/0000-0002-0789-4241 NR 5 TC 7 Z9 7 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0169-4332 J9 APPL SURF SCI JI Appl. Surf. Sci. PD OCT 9 PY 2000 VL 166 IS 1-4 BP 40 EP 44 DI 10.1016/S0169-4332(00)00430-X PG 5 WC Chemistry, Physical; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Chemistry; Materials Science; Physics GA 356EX UT WOS:000089432000008 ER PT J AU Arnold, R Augier, C Baker, J Barabash, A Blum, D Brudanin, V Caffrey, AJ Campagne, JE Caurier, E Dassie, D Egorov, V Filipova, T Gurriaran, R Guyonnet, JL Hubert, F Hubert, P Jullian, S Kisel, I Kochetov, O Kornoukhov, VN Kovalenko, V Lalanne, D Laplanche, F Leccia, F Linck, I Longuemare, C Marquet, C Mauger, F Nicholson, HW Pilugin, I Piquemal, F Reyss, JL Sarazin, X Scheibling, F Suhonen, J Sutton, CS Szklarz, G Timkin, V Torres, R Umatov, V Vanyushin, I Vareille, A Vasilyev, V Vylov, T AF Arnold, R Augier, C Baker, J Barabash, A Blum, D Brudanin, V Caffrey, AJ Campagne, JE Caurier, E Dassie, D Egorov, V Filipova, T Gurriaran, R Guyonnet, JL Hubert, F Hubert, P Jullian, S Kisel, I Kochetov, O Kornoukhov, VN Kovalenko, V Lalanne, D Laplanche, F Leccia, F Linck, I Longuemare, C Marquet, C Mauger, F Nicholson, HW Pilugin, I Piquemal, F Reyss, JL Sarazin, X Scheibling, F Suhonen, J Sutton, CS Szklarz, G Timkin, V Torres, R Umatov, V Vanyushin, I Vareille, A Vasilyev, V Vylov, T TI Limits on different Majoron decay modes of Mo-100, Cd-116, Se-82 and Zr-96 for neutrinoless double beta decays in the NEMO-2 experiment SO NUCLEAR PHYSICS A LA English DT Article DE Majoron; double-beta decay ID BROKEN LEPTON NUMBER; EMISSION; BOSONS; XE-136; CA-48; GE-76 AB The NEMO-2, tracking detector located in the Frejus Underground Laboratory was designed as a prototype For the NEMO-3 detector and to study different modes of double beta decay. Measurements with Mo-100, Cd-116. Se-82, and Zr-96 were carried out. Presented here are the experimental half-life limits on double beta decays for new Majoron emission modes and limits on effective neutrino-Majoron coupling constants. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Inst Theoret & Expt Phys, Moscow 117259, Russia. CNRS, CENBG, IN2P3, F-33170 Gradignan, France. Univ Bordeaux, F-33170 Gradignan, France. Univ Caen, F-14032 Caen, France. CNRS, LPC, IN2P3, F-14032 Caen, France. Joint Inst Nucl Res Dubna, Dubna 141980, Russia. CNRS, CFR, F-91190 Gif Sur Yvette, France. INEEL, Idaho Falls, ID 83415 USA. Univ Jyvaskyla, SF-40351 Jyvaskyla, Finland. Univ Paris Sud, F-91405 Orsay, France. CNRS, IN2P3, LAL, F-91405 Orsay, France. Mt Holyoke Coll, S Hadley, MA 01075 USA. CNRS, IN2P3, IRES, F-67037 Strasbourg, France. Univ Louis Pasteur Strasbourg 1, F-67037 Strasbourg, France. RP Barabash, A (reprint author), Inst Theoret & Expt Phys, Moscow 117259, Russia. RI Caffrey, Augustine/C-2005-2009; Barabash, Alexander/S-8851-2016 NR 44 TC 23 Z9 23 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 OCT 9 PY 2000 VL 678 IS 3 BP 341 EP 352 DI 10.1016/S0375-9474(00)00326-2 PG 12 WC Physics, Nuclear SC Physics GA 358XJ UT WOS:000089582200007 ER PT J AU Chalmers, G Erdmenger, J AF Chalmers, G Erdmenger, J TI Dual expansions of N=4 super Yang-Mills theory via IIB superstring theory SO NUCLEAR PHYSICS B LA English DT Article ID ADS-CFT CORRESPONDENCE; OPERATOR PRODUCT EXPANSION; DE SITTER SUPERGRAVITY; FIELD-THEORY; ADS/CFT CORRESPONDENCE; GENERAL DIMENSIONS; THEORY CORRELATORS; 4-POINT FUNCTIONS; INSTANTONS; TENSOR AB We examine the dual correspondence between holographic IIB superstring theory and N = 4 super Yang-Mills theory at finite values of the coupling constants. In particular we analyze a field theory strong-coupling expansion which is the S-dual of the planar expansion. This expansion arises naturally as the AdS/CFT dual of the IIB superstring scattering amplitudes given a genus truncation property due to modular invariance. The space-time structure of the contributions to the field theory four-point correlation functions obtained from the IIB scattering elements is investigated in the example of the product of four conserved stress tensors, and is expressed as an infinite sum of field theory triangle integrals. The OPE structure of these contributions to the stress tensor four-point function is analyzed and shown not to give rise to any poles. Quantization of the string in the background of a five-form field strength is performed through a covariantized background field approach, and relations to the N = 4 topological string are found. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Argonne Natl Lab, Div High Energy Phys, Argonne, IL 60439 USA. MIT, Ctr Theoret Phys, Cambridge, MA 02139 USA. RP Chalmers, G (reprint author), Argonne Natl Lab, Div High Energy Phys, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 56 TC 4 Z9 4 U1 0 U2 0 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 OCT 9 PY 2000 VL 585 IS 3 BP 517 EP 553 DI 10.1016/S0550-3213(00)00384-9 PG 37 WC Physics, Particles & Fields SC Physics GA 358WQ UT WOS:000089580500001 ER PT J AU Collar, JI Puibasset, J Girard, TA Limagne, D Miley, HS Waysand, G AF Collar, JI Puibasset, J Girard, TA Limagne, D Miley, HS Waysand, G TI First dark matter limits from a large-mass, low-background, superheated droplet detector SO PHYSICAL REVIEW LETTERS LA English DT Article ID RADIATION-INDUCED NUCLEATION; PULSE-SHAPE DISCRIMINATION; HYDRATE; SEARCH; LIQUID; FLUOROCARBON; RECOIL; WATER AB We report on the fabrication aspects and calibration of the first large active mass (similar to 15 g) modules of SIMPLE, a search for particle dark matter using superheated droplet detectors (SDDs). While still limited by the statistical uncertainty of the small data sample on hand, the first weeks of operation in the new underground laboratory of Rustrel-Pays d'Apt already provide a sensitivity to axially coupled weakly interacting massive particles (WIMPs) competitive with leading experiments, confirming SDDs as a convenient, low-cost alternative for WIMP detection. C1 Univ Paris 07, CNRS, UMR 75 88, Phys Solides Grp, F-75251 Paris 05, France. Univ Paris 06, CNRS, UMR 75 88, Phys Solides Grp, F-75251 Paris, France. CERN, Div EP, CH-1211 Geneva 23, Switzerland. Univ Lisbon, Ctr Fis Nucl, P-1649003 Lisbon, Portugal. Pacific NW Natl Lab, Richland, WA 99352 USA. RP Collar, JI (reprint author), Univ Paris 07, CNRS, UMR 75 88, Phys Solides Grp, F-75251 Paris 05, France. OI Girard, Thomas/0000-0003-4113-880X NR 39 TC 47 Z9 47 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 OCT 9 PY 2000 VL 85 IS 15 BP 3083 EP 3086 DI 10.1103/PhysRevLett.85.3083 PG 4 WC Physics, Multidisciplinary SC Physics GA 362ZH UT WOS:000089807800005 PM 11019272 ER PT J AU Brandenburg, G Ershov, A Gao, YS Kim, DYJ Wilson, R Browder, TE Li, Y Rodriguez, JL Yamamoto, H Bergfeld, T Eisenstein, BI Ernst, J Gladding, GE Gollin, GD Hans, RM Johnson, E Karliner, I Marsh, MA Palmer, M Plager, C Sedlack, C Selen, M Thaler, JJ Williams, J Edwards, KW Janicek, R Patel, PM Sadoff, AJ Ammar, R Bean, A Besson, D Davis, R Kwak, N 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, E 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 Thorndike, EH Jessop, CP Marsiske, H Perl, ML Savinov, V Ugolini, D Zhou, X Coan, TE Fadeyev, V Maravin, Y Narsky, I Stroynowski, R Ye, J Wlodek, T Artuso, M Ayad, R Boulahouache, 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 Marka, S Xu, Z Godang, R Kinoshita, K Lai, IC Schrenk, S Bonvicini, G Cinabro, D McGee, S Perera, LP 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 Sharma, V Asner, DM Eppich, A Hill, TS Morrison, RJ Briere, RA Ferguson, T Vogel, H Behrens, BH Ford, WT Gritsan, A Roy, J Smith, JG Alexander, JP Baker, R Bebek, C Berger, BE Berkelman, K Blanc, F Boisvert, V Cassel, DG Dickson, M Drell, PS Ecklund, KM Ehrlich, R Foland, AD Gaidarev, P Galik, RS Gibbons, L Gittelman, B Gray, SW Hartill, DL Heltsley, BK Hopman, PI Jones, CD Kreinick, DL Lohner, M Magerkurth, A Meyer, TO Mistry, NB Nordberg, E Patterson, JR Peterson, D Riley, D Thayer, JG Thies, PG Urner, D Valant-Spaight, B Warburton, A Avery, P Prescott, C Rubiera, AI Yelton, J Zheng, J AF Brandenburg, G Ershov, A Gao, YS Kim, DYJ Wilson, R Browder, TE Li, Y Rodriguez, JL Yamamoto, H Bergfeld, T Eisenstein, BI Ernst, J Gladding, GE Gollin, GD Hans, RM Johnson, E Karliner, I Marsh, MA Palmer, M Plager, C Sedlack, C Selen, M Thaler, JJ Williams, J Edwards, KW Janicek, R Patel, PM Sadoff, AJ Ammar, R Bean, A Besson, D Davis, R Kwak, N 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, E 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 Thorndike, EH Jessop, CP Marsiske, H Perl, ML Savinov, V Ugolini, D Zhou, X Coan, TE Fadeyev, V Maravin, Y Narsky, I Stroynowski, R Ye, J Wlodek, T Artuso, M Ayad, R Boulahouache, 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 Marka, S Xu, Z Godang, R Kinoshita, K Lai, IC Schrenk, S Bonvicini, G Cinabro, D McGee, S Perera, LP 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 Sharma, V Asner, DM Eppich, A Hill, TS Morrison, RJ Briere, RA Ferguson, T Vogel, H Behrens, BH Ford, WT Gritsan, A Roy, J Smith, JG Alexander, JP Baker, R Bebek, C Berger, BE Berkelman, K Blanc, F Boisvert, V Cassel, DG Dickson, M Drell, PS Ecklund, KM Ehrlich, R Foland, AD Gaidarev, P Galik, RS Gibbons, L Gittelman, B Gray, SW Hartill, DL Heltsley, BK Hopman, PI Jones, CD Kreinick, DL Lohner, M Magerkurth, A Meyer, TO Mistry, NB Nordberg, E Patterson, JR Peterson, D Riley, D Thayer, JG Thies, PG Urner, D Valant-Spaight, B Warburton, A Avery, P Prescott, C Rubiera, AI Yelton, J Zheng, J CA CLEO Collaboration TI Measurements of the mass, total width, and two-photon partial width of the eta(c) meson SO PHYSICAL REVIEW LETTERS LA English DT Article ID DETECTOR AB Using 13.4 fb(-1) of data collected with the CLEO detector at the Cornell Electron Storage Ring, we have observed 300 events for the two-photon production of ground-state pseudoscalar charmonium in the decay eta(c) --> K(S)(0)K(+/-)pi(+/-). We have measured the eta(c) mass to be [2980.4 +/- 2.3 (stat) +/- 0.6 (syst)] MeV and its full width as [27.0 +/- 5.8 (stat) +/- 1.4 (syst)] MeV. We have determined the two-photon partial width of the eta(c) meson to be [7.6 +/- 0.8 (stat) +/- 0.4 (syst) +/- 2.3 (br)] keV, with the last uncertainty associated with the decay branching fraction. C1 Harvard Univ, Cambridge, MA 02138 USA. Univ Hawaii, Honolulu, HI 96822 USA. Univ Illinois, Urbana, IL 61801 USA. Carleton Univ, Ottawa, ON K1S 5B6, 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. 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. Univ Cincinnati, Cincinnati, OH 45221 USA. MIT, Cambridge, MA 02139 USA. RP Brandenburg, G (reprint author), Harvard Univ, Cambridge, MA 02138 USA. RI Warburton, Andreas/N-8028-2013; Briere, Roy/N-7819-2014; Vogel, Helmut/N-8882-2014; Ferguson, Thomas/O-3444-2014; OI Warburton, Andreas/0000-0002-2298-7315; Briere, Roy/0000-0001-5229-1039; Vogel, Helmut/0000-0002-6109-3023; Ferguson, Thomas/0000-0001-5822-3731; Poling, Ronald/0000-0001-7305-4702 NR 7 TC 27 Z9 27 U1 1 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD OCT 9 PY 2000 VL 85 IS 15 BP 3095 EP 3099 DI 10.1103/PhysRevLett.85.3095 PG 5 WC Physics, Multidisciplinary SC Physics GA 362ZH UT WOS:000089807800008 PM 11019275 ER PT J AU Back, BB Baker, MD Barton, DS Basilev, S Bates, BD Baum, R Betts, RR Bialas, A Bindel, R Bogucki, W Budzanowski, A Busza, W Carroll, A Ceglia, M Chang, YH Chen, AE Coghen, T Conner, C Czyz, W Dabrowski, B Decowski, MP Despet, M Fita, P Fitch, J Friedl, M Galuszka, K Ganz, R Garcia, E George, N Godlewski, J Gomes, C Griesmayer, E Gulbrandsen, K Gushue, S Halik, J Halliwell, C Haridas, P Hayes, A Heintzelman, GA Henderson, C Hollis, R Holynski, R Holzman, B Johnson, E Kane, J Katzy, J Kita, W Kotula, J Kraner, H Kucewicz, W Kulinich, P Law, C Lemler, M Ligocki, J Lin, WT Manly, S McLeod, D Michalowski, J Mignerey, A Mulmenstadt, J Neal, M Nouicer, R Olszewski, A Pak, R Park, IC Patel, M Pernegger, H Plesko, M Reed, C Remsberg, LP Reuter, M Roland, C Roland, G Ross, D Rosenberg, L Ryan, J Sanzgiri, A Sarin, P Sawicki, P Scaduto, J Shea, J Sinacore, J Skulski, W Steadman, SG Stephans, GSF Steinberg, P Straczek, A Stodulski, M Strek, M Stopa, Z Sukhanov, A Surowiecka, K Tang, JL Teng, R Trzupek, A Vale, C van Nieuwenhuizen, GJ Verdier, R Wadsworth, B Wolfs, FLH Wosiek, B Wozniak, K Wuosmaa, AH Wyslouch, B Zalewski, K Zychowski, P AF Back, BB Baker, MD Barton, DS Basilev, S Bates, BD Baum, R Betts, RR Bialas, A Bindel, R Bogucki, W Budzanowski, A Busza, W Carroll, A Ceglia, M Chang, YH Chen, AE Coghen, T Conner, C Czyz, W Dabrowski, B Decowski, MP Despet, M Fita, P Fitch, J Friedl, M Galuszka, K Ganz, R Garcia, E George, N Godlewski, J Gomes, C Griesmayer, E Gulbrandsen, K Gushue, S Halik, J Halliwell, C Haridas, P Hayes, A Heintzelman, GA Henderson, C Hollis, R Holynski, R Holzman, B Johnson, E Kane, J Katzy, J Kita, W Kotula, J Kraner, H Kucewicz, W Kulinich, P Law, C Lemler, M Ligocki, J Lin, WT Manly, S McLeod, D Michalowski, J Mignerey, A Mulmenstadt, J Neal, M Nouicer, R Olszewski, A Pak, R Park, IC Patel, M Pernegger, H Plesko, M Reed, C Remsberg, LP Reuter, M Roland, C Roland, G Ross, D Rosenberg, L Ryan, J Sanzgiri, A Sarin, P Sawicki, P Scaduto, J Shea, J Sinacore, J Skulski, W Steadman, SG Stephans, GSF Steinberg, P Straczek, A Stodulski, M Strek, M Stopa, Z Sukhanov, A Surowiecka, K Tang, JL Teng, R Trzupek, A Vale, C van Nieuwenhuizen, GJ Verdier, R Wadsworth, B Wolfs, FLH Wosiek, B Wozniak, K Wuosmaa, AH Wyslouch, B Zalewski, K Zychowski, P CA PHOBOS Collaboration TI Charged-particle multiplicity near midrapidity in central Au plus Au collisions at root(NN)-N-s=56 and 130 GeV SO PHYSICAL REVIEW LETTERS LA English DT Article ID DISTRIBUTIONS; ENERGIES; MODEL; PP AB We present the first measurement of pseudorapidity densities of primary charged particles near midrapidity in Au + Au collisions at root S-NN = 56 and 130 GeV. For the most central collisions, we find the charged-particle pseudorapidity density to be dN/d eta/(/eta/, lambda(1), and lambda(2) Or heavy-quark effective theory. We combine Monte Carlo data for the meson mass spectrum with perturbative calculations of the short-distance behavior, to extract <(Lambda)over bar> and lambda(1) From a formula from HQET. Taking into account uncertainties from fitting the mass dependence and from taking the continuum limit, we find <(Lambda)over bar> = 0.68(-0.12)(+0.02) GeV and lambda(1) = -(0.45 +/- 0.12)GeV2 in the quenched approximation. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. RP Kronfeld, AS (reprint author), Fermi Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. OI Kronfeld, Andreas/0000-0003-2716-1149 NR 60 TC 19 Z9 19 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 OCT 5 PY 2000 VL 490 IS 3-4 BP 228 EP 235 DI 10.1016/S0370-2693(00)00833-9 PG 8 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 361XF UT WOS:000089749000006 ER PT J AU Mazumdar, A Wang, J AF Mazumdar, A Wang, J TI A note on brane inflation SO PHYSICS LETTERS B LA English DT Article ID LARGE EXTRA DIMENSIONS; ASSISTED INFLATION; DOMAIN-WALLS; SUPERGRAVITY; COLLIDERS; GRAVITY; SIGNALS AB We demonstrate that there exists an inflationary solution on the positive tension brane in the Randall-Sundrum scenario, Inflation is driven by a slow-rolling scalar field on the brane and is achieved within the perturbative limit of the radion field. We find that inflation on the positive tension brane results in a slight increase in the separation between the two branes. However, we show that the slow-roll inflation is not possible on the negative tension brane. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ London Imperial Coll Sci Technol & Med, Blackett Lab, Astrophys Grp, London SW7 2BZ, England. Fermi Natl Accelerator Lab, Div Theory, Batavia, IL 60510 USA. RP Mazumdar, A (reprint author), Univ London Imperial Coll Sci Technol & Med, Blackett Lab, Astrophys Grp, Prince Consort Rd, London SW7 2BZ, England. NR 49 TC 14 Z9 14 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 J9 PHYS LETT B JI Phys. Lett. B PD OCT 5 PY 2000 VL 490 IS 3-4 BP 251 EP 257 DI 10.1016/S0370-2693(00)00741-3 PG 7 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 361XF UT WOS:000089749000010 ER PT J AU Lyczkowski, RW Gamwo, IK Gidaspow, D AF Lyczkowski, RW Gamwo, IK Gidaspow, D TI Analysis of flow in a non-aerated hopper containing a square obstacle SO POWDER TECHNOLOGY LA English DT Article DE fluidization; critical flow; hoppers; numerical simulation; experimental validation ID GRANULAR-MATERIALS; FLUIDIZED-BED; HYDRODYNAMICS; EROSION AB The ability to predict gas-solids critical flow is a stringent test of the hydrodynamic model of fluidization. It is much more difficult to predict than single-phase compressible critical flow since there are many different two-phase momentum equation formulations in the literature. The hydrodynamic model presented in this paper, and used to analyze critical discharge flow from a non-aerated hopper containing a square obstacle, has already been validated extensively for a wide variety of experiments. The primary objective of this paper is to directly assess the computational ability of this hydrodynamic model to properly predict gas-solids critical flow. To our knowledge, such an assessment has not been previously performed in the open literature. Agreement with the solids velocity data obtained from particle position measurements using motion pictures is excellent. Important qualitatively observed physical phenomena, such as solids buildup on top and oscillating voidage below the square obstacle, are also predicted. (C) 2000 Elsevier Science S.A. All rights reserved. C1 Argonne Natl Lab, Div Energy Syst, Argonne, IL 60439 USA. Tuskegee Univ, Dept Chem Engn, Tuskegee, AL 36088 USA. IIT, Dept Environm Chem & Engn, Chicago, IL 60616 USA. RP Lyczkowski, RW (reprint author), Argonne Natl Lab, Div Energy Syst, Bldg 362,9700 S Cass Ave, Argonne, IL 60439 USA. NR 13 TC 3 Z9 3 U1 0 U2 1 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0032-5910 J9 POWDER TECHNOL JI Powder Technol. PD OCT 5 PY 2000 VL 112 IS 1-2 SI SI BP 57 EP 62 DI 10.1016/S0032-5910(99)00305-8 PG 6 WC Engineering, Chemical SC Engineering GA 356VZ UT WOS:000089464700008 ER PT J AU Bridges, CB Thompson, WW Meltzer, MI Reeve, GR Talamonti, WJ Cox, NJ Lilac, HA Hall, H Klimov, A Fukuda, K AF Bridges, CB Thompson, WW Meltzer, MI Reeve, GR Talamonti, WJ Cox, NJ Lilac, HA Hall, H Klimov, A Fukuda, K TI Effectiveness and cost-benefit of influenza vaccination of healthy working adults - A randomized controlled trial SO JAMA-JOURNAL OF THE AMERICAN MEDICAL ASSOCIATION LA English DT Article ID ELDERLY PERSONS; EFFICACY; POPULATION; VIRUSES; ILLNESS; IMMUNIZATION; PNEUMONIA; EPIDEMICS; TECUMSEH; IMPACT AB Context Although the cost-effectiveness and cost-benefit of influenza vaccination are well established for persons aged 65 years or older, the benefits for healthy adults younger than 65 years are less clear. Objective To evaluate the effectiveness and cost-benefit of influenza vaccine in preventing influenzalike illness (ILI) and reducing societal costs of ILI among healthy working adults. Design Double-blind, randomized, placebo-controlled trial conducted during 2 influenza seasons. Setting and Participants Healthy adults aged 18 to 64 years and employed full-time by a US manufacturing company (for 1997-1998 season, n=1184; for 1998-1999 season, n=1191). Interventions For each season, participants were randomly assigned to receive either trivalent inactivated influenza vaccine (n =595 in 1997-1998 and n = 587 in 1998-1999) or sterile saline injection (placebo; n = 589 in 1997-1998 and n = 604 in 1998-1999). Participants in 1997-1998 were rerandomized if they participated in 1998-1999. Main Outcome Measures Influenzalike illnesses and associated physician visits and work absenteeism reported in biweekly questionnaires by all participants, and serologically confirmed influenza illness among 23% of participants in each year (n = 275 in 1997-1998; n = 278 in 1998-1999); societal cost of ILI per vaccinated vs unvaccinated person. Results For 1997-1998 and 1998-1999, respectively, 95% (1130/1184) and 99% (1178/1191) of participants had complete follow-up, and 23% in each year had serologic testing. In 1997-1998, when the vaccine virus differed from the predominant circulating viruses, vaccine efficacy against serologically confirmed influenza illness was 50% (P=.33). In this season, vaccination did not reduce ILI, physician visits, or lost workdays; the net societal cost was $65.59 per person compared with no vaccination. In 1998-1999, the vaccine and predominant circulating viruses were well matched. Vaccine efficacy was 86% (P =.001), and vaccination reduced ILI, physician visits, and lost workdays by 34%, 42%, and 32%, respectively. However, vaccination resulted in a net societal cost of $11.17 per person compared with no vaccination. Conclusion Influenza vaccination of healthy working adults younger than 65 years can reduce the rates of ILI, lost workdays, and physician visits during years when the vaccine and circulating viruses are similar, but vaccination may not provide overall economic benefits in most years. C1 Ctr Dis Control & Prevent, Influenza Branch, Div Viral & Rickettsial Dis, Natl Ctr Infect Dis, Atlanta, GA 30333 USA. Ctr Dis Control & Prevent, Off Director, Natl Ctr Infect Dis, Atlanta, GA 30333 USA. Ford Motor Co, Dearborn, MI 48121 USA. Oak Ridge Inst Sci & Educ, Oak Ridge, TN USA. RP Bridges, CB (reprint author), Ctr Dis Control & Prevent, Influenza Branch, Div Viral & Rickettsial Dis, Natl Ctr Infect Dis, MS A-32,1600 Clifton Rd, Atlanta, GA 30333 USA. NR 38 TC 430 Z9 443 U1 3 U2 19 PU AMER MEDICAL ASSOC PI CHICAGO PA 515 N STATE ST, CHICAGO, IL 60610 USA SN 0098-7484 J9 JAMA-J AM MED ASSOC JI JAMA-J. Am. Med. Assoc. PD OCT 4 PY 2000 VL 284 IS 13 BP 1655 EP 1663 DI 10.1001/jama.284.13.1655 PG 9 WC Medicine, General & Internal SC General & Internal Medicine GA 357KY UT WOS:000089501900025 PM 11015795 ER PT J AU Branham, KE Byrd, H Cook, R Mays, JW Gary, GM AF Branham, KE Byrd, H Cook, R Mays, JW Gary, GM TI Preparation of soluble, linear titanium-containing copolymers by the free-radical copolymerization of vinyl titanate monomers with styrene SO JOURNAL OF APPLIED POLYMER SCIENCE LA English DT Article DE laser fusion; titanium-containing copolymer; vinyl titanate; copolymerization; macromolecular modification ID INERTIAL-CONFINEMENT FUSION; SPHERICAL IMPLOSIONS; CATALYSTS; ACIDS; MIX AB Linear, soluble copolymers containing titanium are of interest; for use in targets for inertial-confinement fusion (ICF) experiments because the titanium is a useful spectroscopic probe for studying the nuclear fusion process. Some suitable copolymers have been prepared from vinyl titanate monomers and styrene via free-radical polymerization. Soluble copolymers with molecular weights between 70,000 and 100,000 daltons containing 0.1 atom % titanium can be reliably prepared. These copolymers have been incorporated into targets used in inertial-confinement fusion experiments at Lawrence Livermore National Laboratory. Attempts to prepare identical copolymers using macromolecular modification were unsuccessful and yielded insoluble materials upon reaction of the functionalized copolymers with titanium(IV) isopropoxide. (C) 2000 John Wiley & Sons, Inc. C1 Absorbable Polymer Technol Inc, Pelham, AL 35124 USA. Univ Montevallo, Dept Chem, Montevallo, AL 35115 USA. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Alabama, Dept Chem, Birmingham, AL 35294 USA. RP Gary, GM (reprint author), Absorbable Polymer Technol Inc, 115-B Hilltop Business Dr, Pelham, AL 35124 USA. NR 21 TC 5 Z9 5 U1 0 U2 0 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 0021-8995 J9 J APPL POLYM SCI JI J. Appl. Polym. Sci. PD OCT 3 PY 2000 VL 78 IS 1 BP 190 EP 199 DI 10.1002/1097-4628(20001003)78:1<190::AID-APP230>3.0.CO;2-M PG 10 WC Polymer Science SC Polymer Science GA 339QC UT WOS:000088488600023 ER PT J AU Bunker, BC Carpick, RW Assink, RA Thomas, ML Hankins, MG Voigt, JA Sipola, D de Boer, MP Gulley, GL AF Bunker, BC Carpick, RW Assink, RA Thomas, ML Hankins, MG Voigt, JA Sipola, D de Boer, MP Gulley, GL TI The impact of solution agglomeration on the deposition of self-assembled monolayers SO LANGMUIR LA English DT Article ID SILICA SURFACES; OCTADECYLTRICHLOROSILANE; SILANIZATION; TRANSITION AB Self-assembled monolayers (SAMs) are commonly produced by immersing substrates in organic solutions containing trichlorosilane coupling agents. Unfortunately, such deposition solutions can also form alternate structures, including inverse micelles and lamellar phases. The formation of alternate phases is one reason for the sensitivity of SAM depositions to factors such as the water content of the deposition solvent. if such phases are present, the performance of thin films used for applications such as the minimization of friction and stiction in micromachines can be seriously compromised. Inverse micelle formation has been studied in detail for depositions involving 1H,1H,2H,2H-perfluorodecyltrichlorosilane (FDTS) in isooctane, Nuclear magnetic resonance experiments have been used to monitor the kinetics of hydrolysis and condensation reactions between water and FDTS. Light-scattering experiments show that there is a burst of nucleation at a critical concentration of hydrolyzed FDTS to form high concentrations of spherical agglomerates. Atomic force microscopy results show that the agglomerates then deposit on substrate surfaces. Deposition conditions leading to monolayer formation involve using deposition times that are short relative to the induction time for agglomeration. After deposition, inverse micelles can be converted into lamellar or monolayer structures with appropriate heat treatments if surface concentrations are relatively low. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Carpick, RW (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. RI de Boer, Maarten/C-1525-2013 OI de Boer, Maarten/0000-0003-1574-9324 NR 26 TC 117 Z9 118 U1 3 U2 46 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0743-7463 J9 LANGMUIR JI Langmuir PD OCT 3 PY 2000 VL 16 IS 20 BP 7742 EP 7751 DI 10.1021/la000502q PG 10 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 361NG UT WOS:000089728700031 ER PT J AU Annis, BK Kim, MH Wignall, GD Borodin, O Smith, GD AF Annis, BK Kim, MH Wignall, GD Borodin, O Smith, GD TI A study of the influence of LiI on the chain conformations of poly(ethylene oxide) in the melt by small-angle neutron scattering and molecular dynamics simulations SO MACROMOLECULES LA English DT Article ID IONIC ASSOCIATION; LITHIUM IODIDE; POLYMERS; COMPLEXES AB Small-angle neutron scattering (SANS) experiments and molecular dynamics (MD) simulations have been performed on poly(ethylene oxide)/LiI solutions at a salt concentration corresponding to ether oxygen:li = 1.5:1. Both SANS measurements and simulations revealed a substantial reduction (10-15%) in the radius of gyration of PEO chains in the PEO/LiI solutions compared to chains in the pure melt. The characteristic ratio of PEC chains in the melt as obtained from simulations compared well with the values from SANS experiments. Detailed analysis of the MD trajectories revealed a broad distribution in the number of ether oxygen atoms per 12 repeat unit chain involved in Li+ cation complexation, with a strong preference for zero, three, and six ether oxygen atoms per chain. Chains not directly involved in cation complexation (zero complexing ether oxygen atoms) were found to have chain dimensions similar to those in the pure melt. Chains with one to three ether oxygen atoms involved in cation complexation actually showed an increase in radius of gyration. Chains with four or more ether oxygen atoms involved in cation complexation showed increasingly narrow radius of gyration distributions and decreasing radius of gyration, reflecting tight wrapping of the chains around the Li+ cations. C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Univ Utah, Dept Chem & Fuels Engn, Salt Lake City, UT 84112 USA. Univ Utah, Dept Mat Sci & Engn, Salt Lake City, UT 84112 USA. RP Annis, BK (reprint author), Oak Ridge Natl Lab, Div Chem & Analyt Sci, POB 2008, Oak Ridge, TN 37831 USA. RI Borodin, Oleg/B-6855-2012; OI Borodin, Oleg/0000-0002-9428-5291; Wignall, George/0000-0002-3876-3244 NR 29 TC 27 Z9 27 U1 3 U2 8 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0024-9297 J9 MACROMOLECULES JI Macromolecules PD OCT 3 PY 2000 VL 33 IS 20 BP 7544 EP 7548 DI 10.1021/ma000452w PG 5 WC Polymer Science SC Polymer Science GA 361RA UT WOS:000089735800043 ER PT J AU te Velthuis, SGE Jiang, JS Felcher, GP AF te Velthuis, SGE Jiang, JS Felcher, GP TI Switching of the exchange bias in Fe/Cr(211) double-superlattice structures SO APPLIED PHYSICS LETTERS LA English DT Article ID 100 SUPERLATTICES; ANISOTROPY; BILAYERS; MODEL AB The reversal of the direction of the exchange bias in a "double-superlattice" system which consists of an Fe/Cr antiferromagnetic (AF) superlattice which is ferromagnetically coupled with an Fe/Cr ferromagnetic (F) superlattice through a Cr spacer layer, is observed. Magnetometry and polarized neutron reflectometry show that a switch in the bias direction occurs at a field (similar to 447 Oe) well below the field (14 kOe) necessary to saturate the AF superlattice and well below the field (2 kOe) where the AF superlattice initiates a spin-flop transition. The switching of the exchange bias cannot be explained in terms of a model of uniform rotation, but rather by breakdown into domains and reversal of the AF layers. The transparency of magnetic behavior of the double superlattice may be useful in understanding the behavior of traditional exchange bias systems. (C) 2000 American Institute of Physics. [S0003- 6951(00)00240-0]. C1 Argonne Natl Lab, Argonne, IL 60439 USA. RP te Velthuis, SGE (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 15 TC 9 Z9 9 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 OCT 2 PY 2000 VL 77 IS 14 BP 2222 EP 2224 DI 10.1063/1.1313806 PG 3 WC Physics, Applied SC Physics GA 357WZ UT WOS:000089524900048 ER PT J AU Mirkarimi, PB Stearns, DG AF Mirkarimi, PB Stearns, DG TI Investigating the growth of localized defects in thin films using gold nanospheres SO APPLIED PHYSICS LETTERS LA English DT Article ID EXTREME-ULTRAVIOLET LITHOGRAPHY; DEPOSITION AB The response of a thin film to a localized perturbation at the substrate has been studied using a technique for depositing high densities of monodisperse Au nanospheres of known sizes on silicon substrates. We find that the morphology of a defect nucleated by a gold sphere several tens of nm in diameter can vary strongly with the growth conditions, even when the morphology of the unperturbed film does not. In particular we observed that the angle of incidence of the deposition flux plays a strong role in defect evolution during film growth, and that defect smoothing is enhanced when the deposition flux is directed nearly normal to the substrate surface. This work opens the door for a greater understanding of film growth on substrate defects and significantly impacts emerging technologies such as extreme ultraviolet lithography. (C) 2000 American Institute of Physics. [S0003-6951(00)01740-X]. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. OS Associates, Mt View, CA 94040 USA. RP Mirkarimi, PB (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 14 TC 47 Z9 48 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 OCT 2 PY 2000 VL 77 IS 14 BP 2243 EP 2245 DI 10.1063/1.1314291 PG 3 WC Physics, Applied SC Physics GA 357WZ UT WOS:000089524900055 ER PT J AU LeBlond, N Mercier, HPA Dixon, DA Schrobilgen, GJ AF LeBlond, N Mercier, HPA Dixon, DA Schrobilgen, GJ TI Syntheses and structures of TcOF5 and the Tc2O2F9+ cation and formation of the TcOF4+ cation in solution SO INORGANIC CHEMISTRY LA English DT Article ID NUCLEAR-MAGNETIC-RESONANCE; DENSITY-FUNCTIONAL THEORY; NMR CHEMICAL-SHIFTS; EFFECTIVE CORE POTENTIALS; RAY CRYSTAL-STRUCTURE; MOLECULAR CALCULATIONS; VIBRATIONAL-SPECTRA; TRINUCLEAR FLUOROOXOANIONS; LOCALIZED QUANTITIES; XENON(II) COMPOUNDS AB The last member of the series of technetium(VII) oxide fluorides, TcOF5, has been prepared by oxidative fluorination of TcO2F3 with KrF2 in anhydrous HF. The pseudooctahedral (C-4v) structure Of TcOF5 has been determined by F-19 and Tc-99 NMR, Raman, and infrared spectroscopies and by single-crystal X-ray diffraction. TcOF5 crystallizes in the orthorhombic crystal system, space group Pna2(1), with a = 9.235(3) Angstrom, b = 4.939(2) Angstrom, c = 8.502(3) Angstrom, V = 387.7(2) Angstrom(3), and Z = 4 at -102 degrees C, R-1 = 0.0256 and wR(2) = 0.0730. TcOF5 behaves as a fluoride ion donor toward AsF5 and SbF5 in HF solvent, giving the Tc2O2F9+ cation, which has been characterized as the AsF6- and Sb2F11- salts by Raman spectroscopy and as the [Tc2O2F9][Sb2F11] Salt by single-crystal X-ray diffraction. [Tc2O2F9][Sb2F11] crystallizes in the orthorhombic crystal system, space group Pbcm, with a = 6.2925(4) Angstrom, b = 21.205(2) Angstrom, c = 11.7040(8) Angstrom, V = 1561.7(2) Angstrom(3), and Z = 8 at -90 degrees C, R-1 = 0.0368 and wR(2) = 0.0896. The Tc2O2F9+ cation consists of two fluorine-bridged square pyramidal TcOF4 groups in which the fluorine bridge is trans to the oxygens. Solution F-19 and Tc-99 NMR spectra of Tc2O2F9+ salts in HF and of TcOF5 dissolved in SbF5 are consistent with the formation of the TcOF4+ cation. Local density functional theory has been used to calculate the geometrical parameters, vibrational frequencies, and F-19 and Tc-99 NMR parameters of MOF5 (M = Tc, Re, Os) and TC2O2F9+, which are in good agreement with available experimental values. The results of ab initio calculations and normal coordinate analyses for MOF5 confirm the trans influence of oxygen, which leads to lengthening of the axial fluorine-metal bond length and a correspondingly lower stretching force constant relative to that of the shorter equatorial metal-fluorine bonds. C1 McMaster Univ, Dept Chem, Hamilton, ON L8S 4M1, Canada. Pacific NW Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP McMaster Univ, Dept Chem, 1280 Main St W, Hamilton, ON L8S 4M1, Canada. NR 81 TC 15 Z9 15 U1 0 U2 8 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 OCT 2 PY 2000 VL 39 IS 20 BP 4494 EP 4509 DI 10.1021/ic991397e PG 16 WC Chemistry, Inorganic & Nuclear SC Chemistry GA 361DN UT WOS:000089707500016 ER PT J AU Idachaba, MA Nyavor, K Egiebor, NO Rogers, RD AF Idachaba, MA Nyavor, K Egiebor, NO Rogers, RD TI Development of a biofilm formation method for waste forms stability evaluation SO JOURNAL OF HAZARDOUS MATERIALS LA English DT Article DE biofilm; Thiobacillus thiooxidants; Nuclear Regulatory Commission (NRC); microbially induced degradation (MID); waste forms ID HAMBURG SEWER SYSTEM; CORRODED CONCRETE; CORROSION AB The development of an accurate assessment protocol is critical for the prediction of long-term performance of waste disposal systems under field conditions. In this study, the development of a biofilm formation method for the evaluation of waste forms stability to microbially induced degradation (MID) is reported. The development process involved significant modifications to the existing Nuclear Regulatory Commission (NRC) approach, In the biofilm formation method, the control media and fermenter broths are designed to be of similar pH to avoid overestimation of the microbe's capability to degrade the waste forms. In the NRC approach, the pH values are different, The existing one-stage process of the NRC approach is also replaced with a two-stage process in the biofilm formation method. This is to ensure full evaluation of the microbe's involvement in waste forms degradation. The first stage of the two-stage process is for biofilm formation and the second is for biofilm evaluation. The use of a two-stage process eliminates the possibility of substrate limitation, resulting in values of degradation indices that are about two times higher than those obtained using the single-stage NRC approach. Two waste forms (100% Tuskegee cement and 21% cobalt chloride/79% cement) were used in the development of the biofilm formation method. Both waste forms showed evidence of biofilm formation. The formation of biofilm on the cobalt-containing waste form indicates a lack of anti-microbial capability of cobalt. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Tuskegee Univ, Dept Chem Engn, Environm Engn Program, Tuskegee, AL 36088 USA. EG&G Idaho Inc, Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. RP Egiebor, NO (reprint author), Tuskegee Univ, Dept Chem Engn, Environm Engn Program, Tuskegee, AL 36088 USA. NR 11 TC 8 Z9 9 U1 2 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-3894 J9 J HAZARD MATER JI J. Hazard. Mater. PD OCT 2 PY 2000 VL 77 IS 1-3 BP 133 EP 147 DI 10.1016/S0304-3894(00)00236-3 PG 15 WC Engineering, Environmental; Engineering, Civil; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 353WJ UT WOS:000089298200010 PM 10946124 ER PT J AU Roulier, M Kemper, M Al-Abed, S Murdoch, L Cluxton, P Chen, JL Davis-Hoover, W AF Roulier, M Kemper, M Al-Abed, S Murdoch, L Cluxton, P Chen, JL Davis-Hoover, W TI Feasibility of electrokinetic soil remediation in horizontal Lasagna (TM) cells SO JOURNAL OF HAZARDOUS MATERIALS LA English DT Article DE Lasagna (TM) process; electrokinetics; soil; remediation; hydraulic fracturing ID FIELD-TEST; LABORATORY EXPERIMENTS; TECHNOLOGY; ELECTROOSMOSIS; FRACTURES AB An integrated soil remediation technology called Lasagna(TM) has been developed that combines electrokinetics with treatment zones for use in low permeability soils where the rates of hydraulic and electrokinetic transport are too low to be useful for remediation of contaminants. The technology was developed by two groups, one involving industrial partners and the DOE and another involving US EPA and the University of Cincinnati, who pursued different electrode geometries. The Industry/DOE group has demonstrated the technology using electrodes and treatment tunes installed vertically from the soil surface. We have demonstrated the feasibility of installing horizontal electrodes and treatment zones in subsurface soils by hydraulic fracturing, a process that we adapted from petroleum industry practices. When horizontal electrodes were connected to a de power supply, uniform electrical potential gradients of 10-40 V/m were created in soil between the electrodes, inducing electroosmotic flow that facilitated movement of water and contaminants into treatment zones between the electrodes. Published by Elsevier Science B.V. C1 US EPA, Natl Risk Management Res Lab, Cincinnati, OH 45268 USA. Clemson Univ, Dept Geol Sci, Clemson, SC 29634 USA. Cluxton Instruments Inc, Martinsville, OH 45146 USA. Oak Ridge Inst Sci & Educ, Natl Risk Management Res Lab, Cincinnati, OH 45268 USA. RP Roulier, M (reprint author), US EPA, Natl Risk Management Res Lab, 26 W Martin L King Dr, Cincinnati, OH 45268 USA. NR 20 TC 17 Z9 21 U1 1 U2 17 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-3894 J9 J HAZARD MATER JI J. Hazard. Mater. PD OCT 2 PY 2000 VL 77 IS 1-3 BP 161 EP 176 DI 10.1016/S0304-3894(00)00241-7 PG 16 WC Engineering, Environmental; Engineering, Civil; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 353WJ UT WOS:000089298200012 PM 10946126 ER PT J AU Petit, L Beiden, SV Temmerman, WM Szotek, Z Stocks, GM Gehring, GA AF Petit, L Beiden, SV Temmerman, WM Szotek, Z Stocks, GM Gehring, GA TI Screened real-space Korringa-Kohn-Rostoker description of the relativistic and magnetic properties of transition metals SO JOURNAL OF PHYSICS-CONDENSED MATTER LA English DT Article ID MAGNETOCRYSTALLINE ANISOTROPY ENERGY; ELECTRONIC-STRUCTURE CALCULATIONS; MULTIPLE-SCATTERING THEORY; GIANT MAGNETORESISTANCE; PRINCIPLES THEORY; NI; SYSTEMS; ALLOYS; COBALT; NICKEL AB The use of the relativistic and spin-polarized real-space Korringa-Kohn-Rostoker (KKR) method is limited to small systems (less than 100 atoms). This is due to the prohibitively large CPU times needed for the inversion of the KKR matrix. To study systems of more than a thousand atoms, we have implemented the concept of a screened reference medium, within the fully relativistic spin-polarized version of the real-space locally self-consistent multiple-scattering method (LSMS). The LSMS method makes use of a local interaction zone (LIZ) for solving the quantum mechanical problem, while the Poisson equation is solved in the whole space. The screened reference medium gives rise to sparse KKR matrices and using state-of-the-art sparse matrix technology a substantial reduction in the CPU times is obtained, enabling applications of the method to systems whose LIZ consists of more than a thousand atoms. The method is benchmarked by application to the elemental transition metals, the ice (face-centred-cubic) Co and Ni, and the bcc (body-centred cubic) Fe, and compared to the results of the conventional k-space methods. The convergence in real space of the magnetic moments, the magnetocrystalline anisotropy energy and the orbital moment anisotropy is discussed in detail. C1 Univ Sheffield, Dept Phys & Astron, Sheffield S3 7RH, S Yorkshire, England. Inst Phys & Chim Mat Strasbourg, F-67037 Strasbourg, France. SERC, Daresbury Lab, Warrington WA4 4AD, Cheshire, England. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Petit, L (reprint author), Univ Sheffield, Dept Phys & Astron, Sheffield S3 7RH, S Yorkshire, England. RI Petit, Leon/B-5255-2008; Stocks, George Malcollm/Q-1251-2016; OI Stocks, George Malcollm/0000-0002-9013-260X; Petit, Leon/0000-0001-6489-9922 NR 33 TC 5 Z9 5 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0953-8984 J9 J PHYS-CONDENS MAT JI J. Phys.-Condes. Matter PD OCT 2 PY 2000 VL 12 IS 39 BP 8439 EP 8454 DI 10.1088/0953-8984/12/39/307 PG 16 WC Physics, Condensed Matter SC Physics GA 365MW UT WOS:000089955900010 ER PT J AU Fang, XG Scott, BL John, KD Kubas, GJ AF Fang, XG Scott, BL John, KD Kubas, GJ TI Synthesis of and small molecule coordination to highly electrophilic cationic manganese(I) and rhenium(I) carbonyl complexes with tied-back phosphites SO ORGANOMETALLICS LA English DT Article ID RAY CRYSTAL-STRUCTURES; HYDROGEN COMPLEXES; METAL FRAGMENTS; ACTIVATION; H-2; DIHYDROGEN; ETHYLENE; LIGANDS; N-2; ETA(2)-SILANE AB Formally 16e highly electrophilic fragments [Mn(CO)(4)(L)I[BArF] with a tied-back phosphite (L = P(OCH2)(3)CMe) coordinate Et2O (5b) or cis-cyclooctene (5c) and are prepared by reaction of the neutral methyl complex Mn(Me)(CO)(4)(L) with [H(OEt2)(2)][BArF] or [Ph3C][BArF] in the presence of cis-cyclooctene (cco), respectively. The solvent-bound rhenium complexes [Re-(CO)(4)(L)(CH2Cl2)][BArF] (6a) and [Re(CO)(3)(L)2(CH2Cl2)I[BArF] (7a) are prepared similarly by reaction of the respective neutral precursors with [Ph3C][BArF] in CH2Cl2. The CH2Cl2 molecule binds tightly to the Re(I) center and could not be removed under high vacuum for hours. However, the CH2Cl2 is readily displaced by Et2O, cco, and Et3SiH to afford ether-, olefin-, and silane-coordinated complexes 6b-d and 7b-d, respectively. While the eta(2)-(H-SiEt3)-coordinated 7d is stable in solution at room temperature and is a rare example of an isolable cationic silane complex, the more electrophilic analogue ed readily decomposes at room temperature to give the hydride-bridged complex ([cis-Re(L)( CO4](2)(mu-H)}{BArF} (10). Solid-state structures of 5c, 10, and 7b have been determined by single-crystal X-ray structural analysis. C1 Univ Calif Los Alamos Natl Lab, Div Chem, Los Alamos, NM 87545 USA. RP Kubas, GJ (reprint author), Univ Calif Los Alamos Natl Lab, Div Chem, MS J514, Los Alamos, NM 87545 USA. RI Scott, Brian/D-8995-2017; OI Scott, Brian/0000-0003-0468-5396; John, Kevin/0000-0002-6181-9330 NR 42 TC 31 Z9 31 U1 0 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0276-7333 J9 ORGANOMETALLICS JI Organometallics PD OCT 2 PY 2000 VL 19 IS 20 BP 4141 EP 4149 DI 10.1021/om0004693 PG 9 WC Chemistry, Inorganic & Nuclear; Chemistry, Organic SC Chemistry GA 362CR UT WOS:000089761500019 ER PT J AU Appel, R Atoyan, GS Bassalleck, B Bergman, DR Cheung, N Dhawan, S Do, H Egger, J Eilerts, S Fischer, H Herold, W Issakov, VV Kaspar, H Kraus, DE Lazarus, DM Lichard, P Lowe, J Lozano, J Ma, H Majid, W Menzel, W Pislak, S Poblaguev, AA Rehak, P Sher, A Thompson, JA Truol, P Zeller, ME AF Appel, R Atoyan, GS Bassalleck, B Bergman, DR Cheung, N Dhawan, S Do, H Egger, J Eilerts, S Fischer, H Herold, W Issakov, VV Kaspar, H Kraus, DE Lazarus, DM Lichard, P Lowe, J Lozano, J Ma, H Majid, W Menzel, W Pislak, S Poblaguev, AA Rehak, P Sher, A Thompson, JA Truol, P Zeller, ME TI Search for lepton flavor violation in K+ decays into a charged pion and two leptons SO PHYSICAL REVIEW LETTERS LA English DT Article ID LIMIT AB A search for lepton flavor violating decays, K+ --> mu(+)mu(+)pi(-), K+ --> pi(+)e(+)mu(-), K+ --> mu(+)e(+)pi(-), was performed using the data collected in Experiment E865 at the Brookhaven Alternating Gradient Synchrotron. No signal was found in any of the decay modes. At the 90% confidence level, the branching ratios are less than 3.0 X 10(-9), 6.4 X 10(-10), 5.2 X 10(-10) 5.0 x 10(-10), and 3.4 X 10(-9), respectively. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. Univ New Mexico, Dept Phys & Astron, Albuquerque, NM 87131 USA. Univ Pittsburgh, Dept Phys & Astron, Pittsburgh, PA 15260 USA. Russian Acad Sci, Inst Nucl Res, Moscow 117312, Russia. Paul Scherrer Inst, CH-5232 Villigen, Switzerland. Yale Univ, Dept Phys, New Haven, CT 06511 USA. Univ Basel, Inst Phys, CH-4056 Basel, Switzerland. Univ Zurich, Inst Phys, CH-8057 Zurich, Switzerland. RP Appel, R (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. RI Lichard, Peter/A-4459-2010 OI Lichard, Peter/0000-0003-1581-8545 NR 10 TC 46 Z9 47 U1 1 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD OCT 2 PY 2000 VL 85 IS 14 BP 2877 EP 2880 DI 10.1103/PhysRevLett.85.2877 PG 4 WC Physics, Multidisciplinary SC Physics GA 358XA UT WOS:000089581400009 PM 11005958 ER PT J AU Jessop, CP Marsiske, H Perl, ML Savinov, V Ugolini, D Zhou, X Coan, TE Fadeyev, V Maravin, Y Narsky, I Stroynowski, R Ye, J Wlodek, T Artuso, M Ayad, R Boulahouache, 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 Csorna, SE Danko, I McLean, KW Marka, S Xu, Z Godang, R Kinoshita, K Lai, IC Schrenk, S Bonvicini, G Cinabro, D McGee, S Perera, LP Zhou, GJ Lipeles, E Schmidtler, M Shapiro, A Sun, WM Weinstein, AJ Wurthwein, F Jaffe, DE Masek, G Paar, HP Potter, EM Prell, S Sharma, V Asner, DM Eppich, A Hill, TS Morrison, RJ Nelson, HN Briere, RA Behrens, BH Ford, WT Gritsan, A Roy, J Smith, JG Alexander, JP Baker, R Bebek, C Berger, BE Berkelman, K Blanc, F Boisvert, V Cassel, DG Dickson, M Drell, PS Ecklund, KM Ehrlich, R Foland, AD Gaidarev, P Gibbons, L Gittelman, B Gray, SW Hartill, DL Heltsley, BK Hopman, PI Jones, CD Kreinick, DL Lohner, M Magerkurth, A Meyer, TO Mistry, NB Nordberg, E Patterson, JR Peterson, D Riley, D Thayer, JG Thies, PG Valant-Spaight, B Warburton, A Avery, P Prescott, C Rubiera, AI Yelton, J Zheng, J Brandenburg, G Ershov, A Gao, YS Kim, DYJ Wilson, R Browder, TE Li, Y Rodriguez, JL Yamamoto, H Bergfeld, T Eisenstein, BI Ernst, J Gladding, GE Gollin, GD Hans, RM Johnson, E Karliner, I Marsh, MA Palmer, M Plager, C Sedlack, C Selen, M Thaler, JJ Williams, J Edwards, KW Janicek, R Patel, PM Sadoff, AJ Ammar, R Bean, A Besson, D Davis, R Kwak, N Zhao, X Anderson, S Frolov, VV Kubota, Y Lee, SJ Mapatra, R O'Neill, JJ Poling, R Riehle, T Smith, A Urheim, J Ahmed, S Alam, MS Athar, SB Jian, L Ling, L Mahmood, AH Saleem, M Timm, S Wappler, F Anastassov, A Duboscq, JE 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 Menon, N Miller, DH Shibata, EI Shipsey, IPJ Pavlunin, V Cronin-Hennessy, D Kwon, Y Lyon, AL Thorndike, EH AF Jessop, CP Marsiske, H Perl, ML Savinov, V Ugolini, D Zhou, X Coan, TE Fadeyev, V Maravin, Y Narsky, I Stroynowski, R Ye, J Wlodek, T Artuso, M Ayad, R Boulahouache, 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 Csorna, SE Danko, I McLean, KW Marka, S Xu, Z Godang, R Kinoshita, K Lai, IC Schrenk, S Bonvicini, G Cinabro, D McGee, S Perera, LP Zhou, GJ Lipeles, E Schmidtler, M Shapiro, A Sun, WM Weinstein, AJ Wurthwein, F Jaffe, DE Masek, G Paar, HP Potter, EM Prell, S Sharma, V Asner, DM Eppich, A Hill, TS Morrison, RJ Nelson, HN Briere, RA Behrens, BH Ford, WT Gritsan, A Roy, J Smith, JG Alexander, JP Baker, R Bebek, C Berger, BE Berkelman, K Blanc, F Boisvert, V Cassel, DG Dickson, M Drell, PS Ecklund, KM Ehrlich, R Foland, AD Gaidarev, P Gibbons, L Gittelman, B Gray, SW Hartill, DL Heltsley, BK Hopman, PI Jones, CD Kreinick, DL Lohner, M Magerkurth, A Meyer, TO Mistry, NB Nordberg, E Patterson, JR Peterson, D Riley, D Thayer, JG Thies, PG Valant-Spaight, B Warburton, A Avery, P Prescott, C Rubiera, AI Yelton, J Zheng, J Brandenburg, G Ershov, A Gao, YS Kim, DYJ Wilson, R Browder, TE Li, Y Rodriguez, JL Yamamoto, H Bergfeld, T Eisenstein, BI Ernst, J Gladding, GE Gollin, GD Hans, RM Johnson, E Karliner, I Marsh, MA Palmer, M Plager, C Sedlack, C Selen, M Thaler, JJ Williams, J Edwards, KW Janicek, R Patel, PM Sadoff, AJ Ammar, R Bean, A Besson, D Davis, R Kwak, N Zhao, X Anderson, S Frolov, VV Kubota, Y Lee, SJ Mapatra, R O'Neill, JJ Poling, R Riehle, T Smith, A Urheim, J Ahmed, S Alam, MS Athar, SB Jian, L Ling, L Mahmood, AH Saleem, M Timm, S Wappler, F Anastassov, A Duboscq, JE 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 Menon, N Miller, DH Shibata, EI Shipsey, IPJ Pavlunin, V Cronin-Hennessy, D Kwon, Y Lyon, AL Thorndike, EH CA CLEO Collaboration TI Study of charmless hadronic B meson decays to pseudoscalar-vector final states SO PHYSICAL REVIEW LETTERS LA English DT Article ID CP-VIOLATION; DETECTOR; PHYSICS; VERTEX AB We report results of searches for charmless hadronic B meson decays to pseudoscalar (pi*(-), K*(-), pi(0), or K-S(0))-vector(rho, K*, or omega) final states. By using 9.7 X 10(6) B (B) over bar pairs collected with the CLEO detector, we report the first observation of B- --> pi(-)rho(0), (B) over bar(0) --> pi(-)omega, and B- --> pi(-)omega, which are expected to be dominated by hadronic b --> u transitions. The measured branching fractions are (10.4+/-(3.3)(3.4)+/-2.1), (27.6+/-(8.4)(7.4) +/- 4.2) X 10(-6), and (11.3 +/- (3.3)(2.9) +/-1.4) X 10(-6), respectively. Branching fraction; upper limits are set for all of the other decay modes investigated. C1 Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. So Methodist Univ, Dallas, TX 75275 USA. Syracuse Univ, Syracuse, NY 13244 USA. Univ Texas, Austin, TX 78712 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 Hawaii Manoa, Honolulu, HI 96822 USA. Univ Illinois, Urbana, IL 61801 USA. Carleton Univ, Ottawa, ON K1S 5B6, 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. Univ Cincinnati, Cincinnati, OH 45221 USA. MIT, Cambridge, MA 02139 USA. Univ Texas Pan Amer, Edinburg, TX 78539 USA. Yonsei Univ, Seoul 120749, South Korea. RP Jessop, CP (reprint author), Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 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; Poling, Ronald/0000-0001-7305-4702 NR 20 TC 78 Z9 78 U1 1 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD OCT 2 PY 2000 VL 85 IS 14 BP 2881 EP 2885 DI 10.1103/PhysRevLett.85.2881 PG 5 WC Physics, Multidisciplinary SC Physics GA 358XA UT WOS:000089581400010 PM 11005959 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 Atac, M Azfar, F Azzi-Bacchetta, P Bacchetta, N Bailey, MW Bailey, S de Barbaro, P Barbaro-Galtieri, A Barnes, VE Barnett, BA Barone, M Bauer, G Bedeschi, F Belforte, S Bellettini, G Bellinger, J Benjamin, D Bensinger, J Beretvas, A Berge, JP Berryhill, J Bevensee, B Bhatti, A Binkley, M Bisello, D 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 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 Ciobanu, CI Clark, AG Connolly, A Conway, J Cooper, J Cordelli, M Cranshaw, J Cronin-Hennessy, D Cropp, R Culbertson, R Dagenhart, D DeJongh, F Dell'Agnello, S Dell'Orso, M Demina, R Demortier, L Deninno, M Derwent, PF Devlin, T Dittmann, JR Donati, S Done, J Dorigo, T Eddy, N Einsweiler, K Elias, JE Engels, E Erdmann, W Errede, D Errede, S Fan, Q Feild, RG 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 Geer, S Gerdes, DW Giannetii, P Giromini, P Glagolev, V Gold, M Goldstein, J Gordon, A Goshaw, AT Gotra, Y Goulianos, K Green, C Groer, L Grosso-Pilcher, C Guenther, M Guillian, G da Costa, JG Guo, RS 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 Hinrichsen, B 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 Kirby, M Kirk, M Kim, BJ Kim, DH Kim, HS Kim, MJ Kim, SH Kim, YK 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, M Latino, G LeCompte, T Lee, AM Lee, K Leone, S Lewis, JD Lindgren, M Liss, TM Liu, JB Liu, YC 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 Miao, T Miller, R Miller, JS Minato, H Miscetti, S Mishina, M Mitselmakher, G Moggi, N Moore, E Moore, R Morita, Y Mulhearn, M Mukherjee, A Muller, T Munar, A Murat, P Murgia, S Musy, M Nachtman, J Nahn, S Nakada, H Nakaya, T Nakano, I Nelson, C Neuberger, D Newman-Holmes, C Ngan, CYP Nicolaidi, P 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 Plunkett, R 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 Riegler, W Ribon, A Rimondi, F Ristori, L Robertson, WJ Robinson, A Rodrigo, T Rolli, S Rosenson, L Roser, R Rossin, R Safonov, A Sakumoto, WK Saltzberg, D 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 Signorelli, G 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 Teng, PK Terashi, K Tether, S Theriot, D 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, CH Wang, MJ Watanabe, T Waters, D Watts, T Webb, R Wenzel, H Wester, WC Wicklund, AB Wicklund, E 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 Atac, M Azfar, F Azzi-Bacchetta, P Bacchetta, N Bailey, MW Bailey, S de Barbaro, P Barbaro-Galtieri, A Barnes, VE Barnett, BA Barone, M Bauer, G Bedeschi, F Belforte, S Bellettini, G Bellinger, J Benjamin, D Bensinger, J Beretvas, A Berge, JP Berryhill, J Bevensee, B Bhatti, A Binkley, M Bisello, D 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 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 Ciobanu, CI Clark, AG Connolly, A Conway, J Cooper, J Cordelli, M Cranshaw, J Cronin-Hennessy, D Cropp, R Culbertson, R Dagenhart, D DeJongh, F Dell'Agnello, S Dell'Orso, M Demina, R Demortier, L Deninno, M Derwent, PF Devlin, T Dittmann, JR Donati, S Done, J Dorigo, T Eddy, N Einsweiler, K Elias, JE Engels, E Erdmann, W Errede, D Errede, S Fan, Q Feild, RG 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 Geer, S Gerdes, DW Giannetii, P Giromini, P Glagolev, V Gold, M Goldstein, J Gordon, A Goshaw, AT Gotra, Y Goulianos, K Green, C Groer, L Grosso-Pilcher, C Guenther, M Guillian, G da Costa, JG Guo, RS 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 Hinrichsen, B 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 Kirby, M Kirk, M Kim, BJ Kim, DH Kim, HS Kim, MJ Kim, SH Kim, YK 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, M Latino, G LeCompte, T Lee, AM Lee, K Leone, S Lewis, JD Lindgren, M Liss, TM Liu, JB Liu, YC 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 Miao, T Miller, R Miller, JS Minato, H Miscetti, S Mishina, M Mitselmakher, G Moggi, N Moore, E Moore, R Morita, Y Mulhearn, M Mukherjee, A Muller, T Munar, A Murat, P Murgia, S Musy, M Nachtman, J Nahn, S Nakada, H Nakaya, T Nakano, I Nelson, C Neuberger, D Newman-Holmes, C Ngan, CYP Nicolaidi, P 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 Plunkett, R 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 Riegler, W Ribon, A Rimondi, F Ristori, L Robertson, WJ Robinson, A Rodrigo, T Rolli, S Rosenson, L Roser, R Rossin, R Safonov, A Sakumoto, WK Saltzberg, D 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 Signorelli, G 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 Teng, PK Terashi, K Tether, S Theriot, D 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, CH Wang, MJ Watanabe, T Waters, D Watts, T Webb, R Wenzel, H Wester, WC Wicklund, AB Wicklund, E 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 J/psi and psi(2S) polarization in p(p)over-bar collisions at root s=1.8 TeV SO PHYSICAL REVIEW LETTERS LA English DT Article ID CHARMONIUM PRODUCTION; FERMILAB-TEVATRON; FRAGMENTATION AB We have measured the polarization of J/psi and psi(2S) mesons produced in p (p) over bar collisions at root s = 1.8 TeV. using data collected at the Collider Detector at Fermilab during 1992-1995. The polarization of promptly produced J/psi [psi(2S)] mesons is isolated from those produced in B-hadron decay, and measured over the kinematic range 4 [5.5] < P-T < 20 GeV/c and \y\ < 0.6. For P-T greater than or similar to 12 GeV/c we do not observe significant polarization in the prompt component. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Acad Sinica, Inst Phys, Taipei 11529, Taiwan. Argonne Natl Lab, Argonne, IL 60439 USA. Univ Bologna, Ist Nazl Fis Nucl, I-40127 Bologna, Italy. Brandeis Univ, Waltham, MA 02254 USA. Univ Calif Los Angeles, Los Angeles, CA 90024 USA. Univ Cantabria, Inst Fis Cantabria, CSIC, E-39005 Santander, Spain. Univ Chicago, Enrico Fermi Inst, Chicago, IL 60637 USA. Joint 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. 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, Korean Hadron Collider Lab, Taegu 702701, South Korea. Seoul Natl Univ, Seoul 151742, South Korea. Sungkyunkwan Univ, Suwon 440746, South Korea. High Energy Accelerator Res Org, KEK, Oho, Ibaraki 305, Japan. MIT, Cambridge, MA 02139 USA. McGill Univ, Inst Particle Phys, Montreal, PQ H3A 2T8, Canada. Univ Toronto, 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), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RI Lancaster, Mark/C-1693-2008; Vucinic, Dejan/C-2406-2008; Nomerotski, Andrei/A-5169-2010; Azzi, Patrizia/H-5404-2012; Punzi, Giovanni/J-4947-2012; Chiarelli, Giorgio/E-8953-2012; Scodellaro, Luca/K-9091-2014; Paulini, Manfred/N-7794-2014; Introzzi, Gianluca/K-2497-2015; Prokoshin, Fedor/E-2795-2012 OI Azzi, Patrizia/0000-0002-3129-828X; Punzi, Giovanni/0000-0002-8346-9052; Chiarelli, Giorgio/0000-0001-9851-4816; Scodellaro, Luca/0000-0002-4974-8330; Paulini, Manfred/0000-0002-6714-5787; Introzzi, Gianluca/0000-0002-1314-2580; Prokoshin, Fedor/0000-0001-6389-5399 NR 13 TC 180 Z9 182 U1 0 U2 10 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD OCT 2 PY 2000 VL 85 IS 14 BP 2886 EP 2891 DI 10.1103/PhysRevLett.85.2886 PG 6 WC Physics, Multidisciplinary SC Physics GA 358XA UT WOS:000089581400011 PM 11005960 ER PT J AU Thomas, AW Melnitchouk, W Steffens, FM AF Thomas, AW Melnitchouk, W Steffens, FM TI Dynamical symmetry breaking in the sea of the nucleon SO PHYSICAL REVIEW LETTERS LA English DT Article ID CHIRAL PERTURBATION-THEORY; FLAVOR ASYMMETRY; MESON CLOUD; PROTON; MODEL; SPIN AB We derive the nonanalytic chiral behavior of the flavor asymmetry (d) over bar - (u) over bar. Such behavior is a unique characteristic of Goldstone boson loops in chiral theories, including QCD, and establishes the unambiguous role played by the Goldstone bosom cloud in the sea of the proton. Generalizing the results to the SU(3) sector, we show that strange chiral loops require that the s - (s) over bar distribution be nonzero. C1 Univ Adelaide, Special Res Ctr Subatom Struct Matter, Adelaide, SA 5005, Australia. Univ Adelaide, Dept Phys & Math Phys, Adelaide, SA 5005, Australia. Jefferson Lab, Newport News, VA 23606 USA. USP, Inst Fis, BR-05315970 Sao Paulo, Brazil. RI Thomas, Anthony/G-4194-2012 OI Thomas, Anthony/0000-0003-0026-499X NR 28 TC 65 Z9 65 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 OCT 2 PY 2000 VL 85 IS 14 BP 2892 EP 2894 DI 10.1103/PhysRevLett.85.2892 PG 3 WC Physics, Multidisciplinary SC Physics GA 358XA UT WOS:000089581400012 PM 11005961 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 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 Sorensen, SP Stankus, P Stefanek, G Steinberg, P Stenlund, E Stuken, D Sumbera, M Svensson, T Trivedi, MD Tsvetkov, A Tykarski, L Urbahn, J van der Pijll, EC van Eijndhoven, N van Nieuwenhuizen, GJ Vinogradov, A Viyogi, YP Vodopianov, A 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 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 Sorensen, SP Stankus, P Stefanek, G Steinberg, P Stenlund, E Stuken, D Sumbera, M Svensson, T Trivedi, MD Tsvetkov, A Tykarski, L Urbahn, J van der Pijll, EC van Eijndhoven, N van Nieuwenhuizen, GJ Vinogradov, A Viyogi, YP Vodopianov, A Voros, S Wyslouch, B Yagi, K Yokota, Y Young, GR TI Three-pion interferometry results from central Pb plus Pb collisions at 158A GeV/c SO PHYSICAL REVIEW LETTERS LA English DT Article ID MULTISTEP AVALANCHE CHAMBER; HEAVY-ION COLLISIONS; 3-PION CORRELATIONS; PB+PB COLLISIONS; PERFORMANCE; TRACKING; MODEL AB Three-particle correlations have been measured for identified pi(-) from central 158A GeV Pb + Pb collisions by the WA98 experiment at CERN. A substantial contribution of the genuine three-body correlation has been found as expected for a mainly chaotic and symmetric source. C1 Panjab Univ, Chandigarh 160014, India. Univ Rajasthan, Jaipur 302004, Rajasthan, India. Bhabha Atom Res Ctr, Ctr Variable Energy Cyclotron, Calcutta 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. GSI Darmstadt, D-64220 Darmstadt, Germany. Univ Utrecht, NIKHEF, NL-3508 TA Utrecht, Netherlands. Univ Lund, 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 Kampert, Karl-Heinz/0000-0002-2805-0195; Peitzmann, Thomas/0000-0002-7116-899X; Lohner, Herbert/0000-0002-7441-739X; Sumbera, Michal/0000-0002-0639-7323; Mohanty, Bedangadas/0000-0001-9610-2914 NR 18 TC 31 Z9 31 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 OCT 2 PY 2000 VL 85 IS 14 BP 2895 EP 2899 DI 10.1103/PhysRevLett.85.2895 PG 5 WC Physics, Multidisciplinary SC Physics GA 358XA UT WOS:000089581400013 PM 11005962 ER PT J AU Xu, W Dutta, D Xiong, F Anderson, B Auberbach, L Averett, T Bertozzi, W Black, T Calarco, J Cardman, L Cates, GD Chai, ZW Chen, JP Choi, S Chudakov, E Churchwell, S Corrado, GS Crawford, C Dale, D Deur, A Djawotho, P Filippone, BW Finn, JM Gao, H Gilman, R Glamazdin, AV Glashausser, C Glockle, W Golak, J Gomez, J Gorbenko, VG Hansen, JO Hersman, FW Higinbotham, DW Holmes, R Howell, CR Hughes, E Humensky, B Incerti, S de Jager, CW Jensen, JS Jiang, X Jones, CE Jones, M Kahl, R Kamada, H Kievsky, A Kominis, I Korsch, W Kramer, K Kumbartzki, G Kuss, M Lakuriqi, E Liang, M Liyanage, N LeRose, J Malov, S Margaziotis, DJ Martin, JW McCormick, K McKeown, RD McIlhany, K Meziani, ZE Michaels, R Miller, GW Pace, E Pavlin, T Petratos, GG Pomatsalyuk, RI Pripstein, D Prout, D Ransome, RD Roblin, Y Rvachev, M Saha, A Salme, G Schnee, M Shin, T Slifer, K Souder, PA Strauch, S Suleiman, R Sutter, M Tipton, B Todor, L Viviani, M Vlahovic, B Watson, J Williamson, CF Witala, H Wojtsekhowski, B Yeh, J Zolnierczuk, P AF Xu, W Dutta, D Xiong, F Anderson, B Auberbach, L Averett, T Bertozzi, W Black, T Calarco, J Cardman, L Cates, GD Chai, ZW Chen, JP Choi, S Chudakov, E Churchwell, S Corrado, GS Crawford, C Dale, D Deur, A Djawotho, P Filippone, BW Finn, JM Gao, H Gilman, R Glamazdin, AV Glashausser, C Glockle, W Golak, J Gomez, J Gorbenko, VG Hansen, JO Hersman, FW Higinbotham, DW Holmes, R Howell, CR Hughes, E Humensky, B Incerti, S de Jager, CW Jensen, JS Jiang, X Jones, CE Jones, M Kahl, R Kamada, H Kievsky, A Kominis, I Korsch, W Kramer, K Kumbartzki, G Kuss, M Lakuriqi, E Liang, M Liyanage, N LeRose, J Malov, S Margaziotis, DJ Martin, JW McCormick, K McKeown, RD McIlhany, K Meziani, ZE Michaels, R Miller, GW Pace, E Pavlin, T Petratos, GG Pomatsalyuk, RI Pripstein, D Prout, D Ransome, RD Roblin, Y Rvachev, M Saha, A Salme, G Schnee, M Shin, T Slifer, K Souder, PA Strauch, S Suleiman, R Sutter, M Tipton, B Todor, L Viviani, M Vlahovic, B Watson, J Williamson, CF Witala, H Wojtsekhowski, B Yeh, J Zolnierczuk, P TI Transverse asymmetry A(T ') from the quasielastic (3)(H)over-right-arrowe((e)over-right-arrow, e ') process and the neutron magnetic form factor SO PHYSICAL REVIEW LETTERS LA English DT Article ID INCLUSIVE ELECTRON-SCATTERING; QUASI-ELASTIC SCATTERING; FINAL-STATE INTERACTIONS; POLARIZED HE-3; FULL INCLUSION; NUCLEON; TARGETS; H-3 AB We have measured the transverse asymmetry A(T') in (3)(H) over right arrow e((e) over right arrow, e') quasielastic scattering in Hall A at Jefferson Laboratory with high precision for e values from 0.1 to 0.6 (GeV/c)(2). The neutron magnetic form factor G(M)(n) was extracted based on Faddeev calculations for Q(2) = 0.1 and 0.2 (GeV/c)(2) with an experimental uncertainty of less than 2%. C1 MIT, Cambridge, MA 02139 USA. CALTECH, Pasadena, CA 91125 USA. Calif State Univ Los Angeles, Los Angeles, CA 90032 USA. Coll William & Mary, Williamsburg, VA 23187 USA. Duke Univ, Durham, NC 27708 USA. Ist Nazl Fis Nucl, Sez Pisa, Pisa, Italy. Ist Nazl Fis Nucl, Sez Roma, I-00185 Rome, Italy. Ist Nazl Fis Nucl, Sez Tor Vergata, I-00133 Rome, Italy. Jagiellonian Univ, Inst Phys, PL-30059 Krakow, Poland. Kharkov Phys & Technol Inst, UA-310108 Kharkov, Ukraine. Kent State Univ, Kent, OH 44242 USA. Univ Blaise Pascal, LPC, F-63177 Clermont Ferrand, France. N Carolina Cent Univ, Durham, NC 27707 USA. Old Dominion Univ, Norfolk, VA 23508 USA. Princeton Univ, Princeton, NJ 08544 USA. Ruhr Univ Bochum, D-44780 Bochum, Germany. Rutgers State Univ, Piscataway, NJ 08855 USA. Syracuse Univ, Syracuse, NY 13244 USA. Temple Univ, Philadelphia, PA 19122 USA. Thomas Jefferson Natl Accelerator Facil, Newport News, VA 23606 USA. Univ Kentucky, Lexington, KY 40506 USA. Univ New Hampshire, Durham, NH 03824 USA. Univ Roma Tor Vergata, Dipartimento Fis, I-00173 Rome, Italy. Univ Virginia, Charlottesville, VA 22903 USA. RP Xu, W (reprint author), MIT, 77 Massachusetts Ave, Cambridge, MA 02139 USA. RI kievsky, alejandro/A-7123-2011; Kominis, Iannis/C-5515-2011; Averett, Todd/A-2969-2011; Gao, Haiyan/G-2589-2011; Kuss, Michael/H-8959-2012; Higinbotham, Douglas/J-9394-2014 OI Higinbotham, Douglas/0000-0003-2758-6526 NR 34 TC 149 Z9 151 U1 1 U2 4 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD OCT 2 PY 2000 VL 85 IS 14 BP 2900 EP 2904 DI 10.1103/PhysRevLett.85.2900 PG 5 WC Physics, Multidisciplinary SC Physics GA 358XA UT WOS:000089581400014 PM 11005963 ER PT J AU Ortiz, CE Garcia, A Waltz, RA Bhattacharya, M Komives, AK AF Ortiz, CE Garcia, A Waltz, RA Bhattacharya, M Komives, AK TI Shape of the B-8 alpha and neutrino spectra SO PHYSICAL REVIEW LETTERS LA English DT Article ID BETA-DECAY; LI-8 AB The beta-delayed alpha spectrum from the decay of B-8 has been measured with a setup that minimized systematic uncertainties that affected previous measurements; Consequently the deduced neutrino spectrum presents much smaller uncertainties than the previous recommendation [J. N. Bahcall et al., Phys. Rev. C 54, 411 (1996)]. The B-8 nu spectrum is found to be harder than previously recommended with about (10-20)% more neutrinos at energies between 12-14 MeV. The integrated cross sections of the Cl-37, Ga-71, Ar-40, and Super-Kamiokande detectors are, respectively, 3.6%, 1.4%, 5.7%, and 2.1% larger than previously thought. C1 Univ Notre Dame, Notre Dame, IN 46556 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Bhattacharya, M (reprint author), Univ Notre Dame, Notre Dame, IN 46556 USA. OI Garcia, Alejandro/0000-0001-6056-6645 NR 11 TC 97 Z9 97 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 OCT 2 PY 2000 VL 85 IS 14 BP 2909 EP 2912 DI 10.1103/PhysRevLett.85.2909 PG 4 WC Physics, Multidisciplinary SC Physics GA 358XA UT WOS:000089581400016 PM 11005965 ER PT J AU Snavely, RA Key, MH Hatchett, SP Cowan, TE Roth, M Phillips, TW Stoyer, MA Henry, EA Sangster, TC Singh, MS Wilks, SC MacKinnon, A Offenberger, A Pennington, DM Yasuike, K Langdon, AB Lasinski, BF Johnson, J Perry, MD Campbell, EM AF Snavely, RA Key, MH Hatchett, SP Cowan, TE Roth, M Phillips, TW Stoyer, MA Henry, EA Sangster, TC Singh, MS Wilks, SC MacKinnon, A Offenberger, A Pennington, DM Yasuike, K Langdon, AB Lasinski, BF Johnson, J Perry, MD Campbell, EM TI Intense high-energy proton beams from petawatt-laser irradiation of solids SO PHYSICAL REVIEW LETTERS LA English DT Article ID HOT-ELECTRONS; PLASMA; VELOCITY; EMISSION; TARGETS; PULSES AB An intense collimated beam of high-energy protons is emitted normal to the rear surface of thin Solid targets irradiated at 1 PW power and peak intensity 3 x 10(20) Wcm(-2). Up to 48 J (12%) of the laser energy is transferred to 2 X 10(13) protons of energy >10 MeV. The energy spectrum exhibits a sharp high-energy cutoff as high as 58 MeV on the axis of the beam which decreases in energy with increasing off axis angle. Proton induced nuclear processes have been observed and used to characterize the beam. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. GSI Lab, Darmstadt, Germany. Univ Alberta, Edmonton, AB T6G 2G7, Canada. Osaka Univ, ILE, Suita, Osaka 565, Japan. NASA, George C Marshall Space Flight Ctr, Huntsville, AL 35812 USA. RP Roth, M (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808, Livermore, CA 94550 USA. RI MacKinnon, Andrew/P-7239-2014; Cowan, Thomas/A-8713-2011 OI MacKinnon, Andrew/0000-0002-4380-2906; Cowan, Thomas/0000-0002-5845-000X NR 27 TC 1053 Z9 1080 U1 9 U2 71 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 OCT 2 PY 2000 VL 85 IS 14 BP 2945 EP 2948 DI 10.1103/PhysRevLett.85.2945 PG 4 WC Physics, Multidisciplinary SC Physics GA 358XA UT WOS:000089581400025 PM 11005974 ER PT J AU Heathman, S Haire, RG Le Bihan, T Lindbaum, A Litfin, K Meresse, Y Libotte, H AF Heathman, S Haire, RG Le Bihan, T Lindbaum, A Litfin, K Meresse, Y Libotte, H TI Pressure induces major changes in the nature of americium's 5f electrons SO PHYSICAL REVIEW LETTERS LA English DT Article ID DIFFRACTION AB Americium occupies a pivotal position in the actinide series with regard to the behavior of 5f electrons. High-pressure techniques together with synchrotron radiation have been used to determine the structural behavior up to 100 GPa. We have resolved earlier controversial findings regarding americium and find that our experimental results are in discord with recent theoretical predictions. We have two new findings: (1) that there exists a critical, new structural link between americium under pressure and its near neighbor, plutonium; and (2) that the 5f electron delocalization in americium occurs in two rather than one step. C1 European Commiss, Joint Res Ctr, Inst Transuranium Elements, D-76125 Karlsruhe, Germany. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. European Synchrotron Radiat Facil, F-38043 Grenoble, France. RP Heathman, S (reprint author), European Commiss, Joint Res Ctr, Inst Transuranium Elements, Postfach 2340, D-76125 Karlsruhe, Germany. RI LE BIHAN, Tristan/I-5063-2013 NR 17 TC 100 Z9 100 U1 0 U2 14 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 OCT 2 PY 2000 VL 85 IS 14 BP 2961 EP 2964 DI 10.1103/PhysRevLett.85.2961 PG 4 WC Physics, Multidisciplinary SC Physics GA 358XA UT WOS:000089581400029 PM 11005978 ER PT J AU Carr, GL Lobo, RPSM LaVeigne, J Reitze, DH Tanner, DB AF Carr, GL Lobo, RPSM LaVeigne, J Reitze, DH Tanner, DB TI Exploring the dynamics of superconductors by time-resolved far-infrared spectroscopy SO PHYSICAL REVIEW LETTERS LA English DT Article ID PAIR BREAKING; YBA2CU3O7-DELTA; QUASIPARTICLES; LIFETIMES; LIGHT AB We have examined the recombination of excess quasiparticles in superconducting Pb by time-resolved far-infrared spectroscopy using a pulsed synchrotron source. The energy gap shift calculated by Owen and Scalapino [Phys. Rev. Lett. 28, 1559 (1972)] is directly observed, as is the associated reduction in the Cooper pair density. The relaxation process involves a two-component decay; the faster (similar to 200 ps) is associated with the actual (effective) recombination process, while the slower (similar to 10 to 100 ns) is due to heat transport across the film/substrate interface. The temperature dependence of the recombination process between 0.5T(c) and 0.85T(c) is in good agreement with theory. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. Univ Florida, Dept Phys, Gainesville, FL 32611 USA. RP Carr, GL (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. OI Lobo, Ricardo/0000-0003-2355-6856 NR 19 TC 58 Z9 59 U1 1 U2 9 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD OCT 2 PY 2000 VL 85 IS 14 BP 3001 EP 3004 DI 10.1103/PhysRevLett.85.3001 PG 4 WC Physics, Multidisciplinary SC Physics GA 358XA UT WOS:000089581400039 PM 11005988 ER PT J AU Ben-Naim, E Krapivsky, PL AF Ben-Naim, E Krapivsky, PL TI Fragmentation with a steady source SO PHYSICS LETTERS A LA English DT Article ID MARTENSITE GROWTH; SCALE-INVARIANCE; CROSSOVER; KINETICS AB We investigate fragmentation processes with a steady input of fragments. We find that the size distribution approaches a stationary form which exhibits a power law divergence in the small size limit, P-x(x) similar to x(-3). This algebraic behavior is robust as it is independent of the details of the input as well as the spatial dimension. The full time dependent behavior is obtained analytically for arbitrary inputs, and is found to exhibit a universal scaling behavior. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Univ Calif Los Alamos Natl Lab, Ctr Nonlinear Studies, Los Alamos, NM 87545 USA. Boston Univ, Ctr Polymer Studies, Boston, MA 02215 USA. Boston Univ, Dept Phys, Boston, MA 02215 USA. Univ Toulouse 3, Phys Quant Lab, CNRS, IRSAMC, F-31062 Toulouse, France. RP Ben-Naim, E (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RI Ben-Naim, Eli/C-7542-2009; Krapivsky, Pavel/A-4612-2014 OI Ben-Naim, Eli/0000-0002-2444-7304; NR 32 TC 23 Z9 24 U1 0 U2 3 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 OCT 2 PY 2000 VL 275 IS 1-2 BP 48 EP 53 DI 10.1016/S0375-9601(00)00570-3 PG 6 WC Physics, Multidisciplinary SC Physics GA 362LF UT WOS:000089778900008 ER PT J AU Gustin, MS Lindberg, SE Austin, K Coolbaugh, M Vette, A Zhang, H AF Gustin, MS Lindberg, SE Austin, K Coolbaugh, M Vette, A Zhang, H TI Assessing the contribution of natural sources to regional atmospheric mercury budgets SO SCIENCE OF THE TOTAL ENVIRONMENT LA English DT Article; Proceedings Paper CT 5th International Conference on Mercury as a Global Pollutant CY MAY 23-28, 1999 CL RIO JANEIRO, BRAZIL SP Ctr Miner Technol, Canadian Int Dev Agcy, Brazilian Res Council, Elect Power Res Inst, Res Support Fdn DE mercury; atmosphere; emmisions ID ELEMENTAL MERCURY; TRACE-METALS; SOILS; EMISSIONS; AIR; EXCHANGE; FLUXES; TESTS; SURFACES; CHAMBER AB Naturally mercury-enriched substrate is a long-lived source of mercury to the global atmospheric mercury cycle. Field flux chambers, laboratory gas exchange chambers and micrometeorological methods may be applied to estimate emissions from these sources. However, field chamber experimental design may affect the magnitude of the fluxes measured, and the laboratory chamber only provides a minimum estimate of flux. Many factors, such as mercury concentration and speciation in substrate, light, precipitation, and temperature, influence the emission of mercury from the substrate. Mercury concentration in the substrate is a dominant factor controlling emissions and may be used to predict emissions from regions of mercury enrichment. Mercury fluxes measured from three areas of natural enrichment and three areas with low levels of mercury enrichment are 1-5 orders of magnitude greater than the value applied to global belts of natural enrichment. Preliminary scaling of emissions from one of these areas and for western North America indicates that mercury enriched areas may be significant sources of mercury to the atmosphere, and that their contribution to regional and global atmospheric budgets needs to be reassessed. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Univ Nevada, Dept Environm & Resource Sci MS370, Reno, NV 89557 USA. Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. RP Gustin, MS (reprint author), Univ Nevada, Dept Environm & Resource Sci MS370, Reno, NV 89557 USA. RI Vette, Alan/A-7330-2012 OI Vette, Alan/0000-0001-6749-1252 NR 44 TC 103 Z9 116 U1 0 U2 20 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0048-9697 J9 SCI TOTAL ENVIRON JI Sci. Total Environ. PD OCT 2 PY 2000 VL 259 IS 1-3 BP 61 EP 71 DI 10.1016/S0048-9697(00)00556-8 PG 11 WC Environmental Sciences SC Environmental Sciences & Ecology GA 358ZJ UT WOS:000089586800008 ER PT J AU Zhang, H Lindberg, SE AF Zhang, H Lindberg, SE TI Air/water exchange of mercury in the Everglades I: the behavior of dissolved gaseous mercury in the Everglades Nutrient Removal Project SO SCIENCE OF THE TOTAL ENVIRONMENT LA English DT Article; Proceedings Paper CT 5th International Conference on Mercury as a Global Pollutant CY MAY 23-28, 1999 CL RIO JANEIRO, BRAZIL SP Ctr Miner Technol, Canadian Int Dev Agcy, Brazilian Res Council, Elect Power Res Inst, Res Support Fdn DE biogeochemical cycling; evasion; flux; photochemical transformation; redox; wetlands ID LAKES AB From 1996 to 1998 we determined dissolved gaseous mercury (DGM) in waters of the Everglades Nutrient Removal Project (ENR), a constructed wetlands. The concentrations of DGM measured in these waters (mean 7.3 +/- 9.5 pg l(-1)) are among the lowest reported in the literature, and suggest a system often near or slightly above equilibrium with Kg in ambient air. DGM exhibited both seasonal and diel trends, peaking at midday and during the summer. A simple box budget model of DGM in waters of the Everglades was developed using an interactive spreadsheet based on a mass balance among light-induced reduction of Hg-II (production of DGM), Hg-0 oxidation (removal), and Hg-0 evasion in a box (water column) consisting of a surface region with sunlight available and a lower dark region. The modeling results suggest high sensitivity of hourly DGM concentrations to DGM production rates and initial DGM levels. The sensitivity to Hg oxidation is lower than the sensitivity to DGM production. The model performance demonstrates successful simulations of a variety of DGM trends in the Everglades. In particular, it clearly demonstrates how it is possible to measure comparable rates of evasion over several Everglades sites with different DGM concentrations. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. RP Zhang, H (reprint author), Oak Ridge Natl Lab, Div Environm Sci, POB 2008, Oak Ridge, TN 37831 USA. RI Mason, Robert/A-6829-2011 NR 13 TC 39 Z9 41 U1 0 U2 9 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0048-9697 J9 SCI TOTAL ENVIRON JI Sci. Total Environ. PD OCT 2 PY 2000 VL 259 IS 1-3 BP 123 EP 133 DI 10.1016/S0048-9697(00)00577-5 PG 11 WC Environmental Sciences SC Environmental Sciences & Ecology GA 358ZJ UT WOS:000089586800014 ER PT J AU Lindberg, SE Zhang, H AF Lindberg, SE Zhang, H TI Air/water exchange of mercury in the Everglades II: measuring and modeling evasion of mercury from surface waters in the Everglades Nutrient Removal Project SO SCIENCE OF THE TOTAL ENVIRONMENT LA English DT Article; Proceedings Paper CT 5th International Conference on Mercury as a Global Pollutant CY MAY 23-28, 1999 CL RIO JANEIRO, BRAZIL SP Ctr Miner Technol, Canadian Int Dev Agcy, Brazilian Res Council, Elect Power Res Inst, Res Support Fdn DE atmospheric deposition; dissolved gaseous mercury; flux; heavy metal; wetland ID VOLATILE MERCURY; CHAMBER; SOIL; FLUXES; TESTS; VAPOR; AIR AB During the period 1996-1998, and covering each of the four climatic seasons, we measured evasion of Hg using flux chambers over waters of the Everglades Nutrient Removal Project (ENR), a constructed wetlands. In situ water evasion fluxes of total gaseous mercury (primarily Hg-o) measured at seven Everglades sites typically show low evasion rates (< 3 ng m(-2) h(-1)), which are smaller on average than those measured in northern systems. Evasion exhibits a strong diel cycle, with the highest values during midday, and evasion rates are correlated with dissolved gaseous mercury (DGM), solar radiation, wind speed, and water temperature. A thin film model was adapted and applied to estimate evasion fluxes for these Everglades waters based on our measurements of DGM. The results suggest that the typical thin film model underestimates evasion for the Everglades waters, at least on a short time scale. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. RP Lindberg, SE (reprint author), Oak Ridge Natl Lab, Div Environm Sci, POB 2008, Oak Ridge, TN 37831 USA. RI Mason, Robert/A-6829-2011 NR 19 TC 29 Z9 35 U1 3 U2 15 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0048-9697 J9 SCI TOTAL ENVIRON JI Sci. Total Environ. PD OCT 2 PY 2000 VL 259 IS 1-3 BP 135 EP 143 DI 10.1016/S0048-9697(00)00586-6 PG 9 WC Environmental Sciences SC Environmental Sciences & Ecology GA 358ZJ UT WOS:000089586800015 ER PT J AU Miao, J Kirz, J Sayre, D AF Miao, J Kirz, J Sayre, D TI The oversampling phasing method SO ACTA CRYSTALLOGRAPHICA SECTION D-BIOLOGICAL CRYSTALLOGRAPHY LA English DT Article ID CRYSTALLOGRAPHY; RETRIEVAL AB Sampling the diffraction pattern of a finite specimen more finely than the Nyquist frequency (the inverse of the size of the diffracting specimen) corresponds to surrounding the electron density of the specimen with a no-density region. When the no-density region is bigger than the electron-density region, sufficient information is recorded so that the phase information can be retrieved from the oversampled diffraction pattern, at least in principle. By employing an iterative algorithm, the phase information from the oversampled diffraction pattern of a micrometre-sized test specimen has been successfully retrieved. This method is believed to be able to open a door for high-resolution three-dimensional structure determination of complex and non-crystalline biological specimens, i.e. whole cells and sub-micrometre molecular clusters and micrometre-sized protein crystals. With the possible appearance in the future of X-ray free-electron lasers, it may become possible to image single molecules by recording diffraction patterns before radiation damage manifests itself. C1 SUNY Stony Brook, Dept Phys & Astron, Stony Brook, NY 11794 USA. RP Miao, J (reprint author), Stanford Synchrotron Radiat Lab, POB 4349 MS69, Stanford, CA 94309 USA. NR 13 TC 49 Z9 51 U1 1 U2 13 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0907-4449 J9 ACTA CRYSTALLOGR D JI Acta Crystallogr. Sect. D-Biol. Crystallogr. PD OCT PY 2000 VL 56 BP 1312 EP 1315 DI 10.1107/S0907444900008970 PN 10 PG 4 WC Biochemical Research Methods; Biochemistry & Molecular Biology; Biophysics; Crystallography SC Biochemistry & Molecular Biology; Biophysics; Crystallography GA 357VC UT WOS:000089520600012 PM 10998627 ER PT J AU Stefanski, RJ AF Stefanski, RJ CA E-791 Collaboration TI Preliminary results for two-pion resonances in D+ and D-s(+) -> pi(-)pi(+)pi(+) from Fermilab experiment E-791 SO ACTA PHYSICA POLONICA B LA English DT Article; Proceedings Paper CT 6th International Workshop on Production, Properties and Interaction of Mesons (MESON 2000) CY MAY, 2000 CL KRAKOW, POLAND SP Jagellonian Univ, Inst Phys, Forsch Zentrum, INFN LNF, Inst Nucl Phys Cracow, Polish Acad Sci, Comm Phys AB In this paper we present preliminary results of a coherent amplitude analysis of three-pion decays of charm mesons. The analysis includes a greater number of possible resonant states than in previous analyses, and produces masses and Breit-Wigner widths of the isoscalar resonances f(0)(980) and f(0)(1370) with better precision than previous measurements. We also present preliminary results for the mass and width of the low lying f(0)(400), sometimes called the sigma meson. C1 Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. RP Stefanski, RJ (reprint author), Fermi Natl Accelerator Lab, MS122,POB 500, Batavia, IL 60510 USA. NR 7 TC 1 Z9 1 U1 0 U2 0 PU ACTA PHYSICA POLONICA B, JAGELLONIAN UNIV, INST PHYSICS PI KRAKOW PA REYMONTA 4, 30-059 KRAKOW, POLAND SN 0587-4254 J9 ACTA PHYS POL B JI Acta Phys. Pol. B PD OCT-NOV PY 2000 VL 31 IS 10-11 BP 2521 EP 2528 PG 8 WC Physics, Multidisciplinary SC Physics GA 374DZ UT WOS:000165330300062 ER PT J AU Barnes, T AF Barnes, T TI Exotic mesons, theory and experiment SO ACTA PHYSICA POLONICA B LA English DT Article; Proceedings Paper CT 6th International Workshop on Production, Properties and Interaction of Mesons (MESON 2000) CY MAY, 2000 CL KRAKOW, POLAND SP Jagellonian Univ, Inst Phys, Forschungszentrum Julich, INFN LNF, Inst Nucl Phys Cracow, Polish Acad Sci, Comm Phys ID QQBARG HYBRID MESONS; MIT BAG MODEL; QCD SUM-RULES; FLUX-TUBE MODEL; ETA-PI; HERMAPHRODITE MESONS; MULTIQUARK HADRONS; 18 GEV/C; DECAY; BARYONS AB The status of exotic mesons is summarized, including both theoretical expectations and experimental candidates. The current experimental candidates are "spin-parity exotics"; since these are most often considered possible hybrid mesons, the theoretical discussion will be mainly concerned with hybrids. The exotic meson candidates discussed are the surprisingly light pi (1)(1400) and pi (1)(1600). C1 Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. Univ Bonn, Inst Theoret Kernphys, D-53115 Bonn, Germany. Forschungszentrum Julich, Inst Kernphys, D-52425 Julich, Germany. RP Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. NR 52 TC 8 Z9 8 U1 0 U2 0 PU JAGIELLONIAN UNIV PRESS PI KRAKOW PA UL MICHALOWSKIEGO 9-2, KRAKOW, 31126, POLAND SN 0587-4254 EI 1509-5770 J9 ACTA PHYS POL B JI Acta Phys. Pol. B PD OCT-NOV PY 2000 VL 31 IS 10-11 BP 2545 EP 2556 PG 12 WC Physics, Multidisciplinary SC Physics GA 374DZ UT WOS:000165330300065 ER PT J AU Willutzki, HJ AF Willutzki, HJ CA E852 Collaboration TI Evidence for exotic meson production in pi(-)p interactions at 18 GeV/c SO ACTA PHYSICA POLONICA B LA English DT Article; Proceedings Paper CT 6th International Workshop on Production, Properties and Interaction of Mesons (MESON 2000) CY MAY, 2000 CL KRAKOW, POLAND SP Jagellonian Univ, Inst Phys, Forsch Zentrum, INFN LNF, Inst Nucl Phys Cracow, Polish Acad Sci, Comm Phys ID FLUX-TUBE MODEL; HYBRID MESONS AB The eta pi (-) system has been studied in the reaction pi (-)p --> eta pi (-)p at 18 GeV/c. A large asymmetry in the angular distribution is observed indicating interference between L-even and L-odd partial waves. The data require interference between the a(2)(1320) and an exotic J(PC) = 1(-+) resonance pi (1)(1400) with M = (1370 +/- 16(-30)(+50)) MeV/c(2) and Gamma = (385 +/- 40(-105)(+65)) MeV/c2. A second exotic J(PC) = 1(-+) resonance pi (1)(1600) has been found n p in the rho pi channel. A mass-dependent fit yields M = (1593 +/- 8(-47)(+29)) MeV/c(2) and Gamma = (168 +/- 20(-12)(+150)) MeV/c(2). Presumably the same resonance is also found in the eta'(959)pi (-) final state with M = (1589 +/- 9) MeV/c(2) and Gamma = (380 +/- 22) MeV/c(2). C1 Brookhaven Natl Lab, Upton, NY 11973 USA. RP Willutzki, HJ (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. NR 11 TC 2 Z9 2 U1 0 U2 0 PU ACTA PHYSICA POLONICA B, JAGELLONIAN UNIV, INST PHYSICS PI KRAKOW PA REYMONTA 4, 30-059 KRAKOW, POLAND SN 0587-4254 J9 ACTA PHYS POL B JI Acta Phys. Pol. B PD OCT-NOV PY 2000 VL 31 IS 10-11 BP 2615 EP 2623 PG 9 WC Physics, Multidisciplinary SC Physics GA 374DZ UT WOS:000165330300073 ER PT J AU Barnes, T AF Barnes, T TI MESON 2000 conference summary lite SO ACTA PHYSICA POLONICA B LA English DT Article; Proceedings Paper CT 6th International Workshop on Production, Properties and Interaction of Mesons (MESON 2000) CY MAY, 2000 CL KRAKOW, POLAND SP Jagellonian Univ, Inst Phys, Forschungszentrum Julich, INFN LNF, Inst Nucl Phys Cracow, Polish Acad Sci, Comm Phys AB This short contribution is a lite MESON2000 conference summary. As appropriate for the 600th anniversary of the Jagellonian University, it begins with a brief summary of the last 600 years of European history and its place in hadron physics. Next a "physicist chirality" order parameter PC is introduced. When applied to MESON2000 plenary speakers this order parameter illustrates the separation of hadron physicists into disjoint communities. The individual plenary talks in MESON2000 are next sorted according to the subconference associated with each of the 36 plenary speakers. Finally, I conclude with a previously unreported Feynman story regarding the use of models in hadron physics. C1 Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. Univ Bonn, Inst Theoret Kernphys, D-53115 Bonn, Germany. Forschungszentrum Julich, Inst Kernphys, D-52425 Julich, Germany. RP Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. NR 2 TC 2 Z9 2 U1 0 U2 0 PU JAGIELLONIAN UNIV PRESS PI KRAKOW PA UL MICHALOWSKIEGO 9-2, KRAKOW, 31126, POLAND SN 0587-4254 EI 1509-5770 J9 ACTA PHYS POL B JI Acta Phys. Pol. B PD OCT-NOV PY 2000 VL 31 IS 10-11 BP 2745 EP 2754 PG 10 WC Physics, Multidisciplinary SC Physics GA 374DZ UT WOS:000165330300090 ER PT J AU Ice, GE Larson, BC AF Ice, GE Larson, BC TI 3D X-ray crystal microscope SO ADVANCED ENGINEERING MATERIALS LA English DT Article ID DIFFRACTION; TEXTURE; STRAIN AB Penetrating, submicrometer X-ray beams probe the mesoscopic crystalline structure of polycrystalline materials in three dimensions. Crystalline morphology, strain, texture, and phase can now be studied non-destructively with a spatial resolution below the grain size of most materials. This Mew information will lead to a move complete understanding of the mesoscopic structure and dynamics of materials and their relation to materials properties. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Ice, GE (reprint author), Oak Ridge Natl Lab, Bethel Valley Rd, Oak Ridge, TN 37831 USA. NR 17 TC 76 Z9 76 U1 0 U2 7 PU WILEY-V C H VERLAG GMBH PI BERLIN PA PO BOX 10 11 61, D-69451 BERLIN, GERMANY SN 1438-1656 J9 ADV ENG MATER JI Adv. Eng. Mater. PD OCT PY 2000 VL 2 IS 10 BP 643 EP 646 DI 10.1002/1527-2648(200010)2:10<643::AID-ADEM643>3.3.CO;2-L PG 4 WC Materials Science, Multidisciplinary SC Materials Science GA 370NJ UT WOS:000165128900016 ER PT J AU Ettinger, M Hoyer, P AF Ettinger, M Hoyer, P TI On quantum algorithms for noncommutative hidden subgroups SO ADVANCES IN APPLIED MATHEMATICS LA English DT Article AB Quantum algorithms for factoring and finding discrete logarithms have previously been generalized to finding hidden subgroups of finite Abelian groups. This paper explores the possibility of extending this general viewpoint to finding hidden subgroups of noncommutative groups. We present a quantum algorithm for the special case of dihedral groups which determines the hidden subgroup in a linear number of calls to the input function. We also explore the difficulties of developing an algorithm to process the data to explicitly calculate a generating set for the subgroup. A general framework for the noncommutative hidden subgroup problem is discussed and we indicate future research directions. (C) 2000 Academic Press. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Aarhus Univ, Dept Comp Sci, BRICS, DK-8000 Aarhus C, Denmark. RP Ettinger, M (reprint author), Univ Calif Los Alamos Natl Lab, Mail Stop B-230, Los Alamos, NM 87545 USA. OI Hoyer, Peter/0000-0001-9877-268X NR 17 TC 43 Z9 43 U1 0 U2 0 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0196-8858 J9 ADV APPL MATH JI Adv. Appl. Math. PD OCT PY 2000 VL 25 IS 3 BP 239 EP 251 DI 10.1006/aama.2000.0699 PG 13 WC Mathematics, Applied SC Mathematics GA 360UZ UT WOS:000089686900002 ER PT J AU Sugama, T Weber, L Brothers, LE AF Sugama, T Weber, L Brothers, LE TI Hot acid resistance of polymer-modified calcium aluminate/fly ash/polyphosphate cements SO ADVANCES IN CEMENT RESEARCH LA English DT Article AB To confirm the resistance of sodium polyphosphate-modified class F fly ash/calcium aluminate blend (SFCB) cements to an H2SO4 solution (pH 1.6) at 90 degrees C, various different organic polymer dispersions were incorporated into the cements. It was found that acrylic-styrene copolymer (ASC), with a pH similar to 4 was the most effective in mitigating acid erosion of the cements. The reasons for making them less susceptible to acid attack are due to the following two major roles of ASC The first is ASC's chemical affinity for the Ca2+ ions liberated from monocalcium aluminate (CA) and calcium dialuminate (CA(2)) in the calcium aluminate cement (CAC) reactant, so forming Ca-complexed carboxylate compounds in the interfacial contact zone between ASC and CAC. The other role is related to the coverage of the reaction products by the ASC film and the unreacted CAC and fly ash particles, generating a network structure. These roles significantly restrain the formation of gypsum yielded by the reaction between H2SO4 and CAC. Gypsum is detrimental to the cements because it expands, making them vulnerable to acid erosion, because of its expansion nature. The loss in weight of ASC-modified SFCB cements after exposure for 25 days to hot acid was only 2.6%, compared with 27.3% in unmodified cements after the same exposure time. C1 Brookhaven Natl Lab, Dept Appl Sci, Mat & Chem Sci Div, Upton, NY 11973 USA. Halliburton Energy Serv, Duncan, OK 73536 USA. RP Sugama, T (reprint author), Brookhaven Natl Lab, Dept Appl Sci, Mat & Chem Sci Div, Upton, NY 11973 USA. NR 7 TC 1 Z9 2 U1 0 U2 1 PU THOMAS TELFORD SERVICES LTD PI LONDON PA THOMAS TELFORD HOUSE, 1 HERON QUAY, LONDON, ENGLAND E14 4JD SN 0951-7197 J9 ADV CEM RES JI Adv. Cem. Res. PD OCT PY 2000 VL 12 IS 4 BP 181 EP 189 PG 9 WC Construction & Building Technology; Materials Science, Multidisciplinary SC Construction & Building Technology; Materials Science GA 362JL UT WOS:000089774800006 ER PT J AU Foley, B Pan, H Buchbinder, S Delwart, EL AF Foley, B Pan, H Buchbinder, S Delwart, EL TI Apparent founder effect during the early years of the San Francisco HIV type 1 epidemic (1978-1979) SO AIDS RESEARCH AND HUMAN RETROVIRUSES LA English DT Article ID HUMAN-IMMUNODEFICIENCY-VIRUS; HETERODUPLEX MOBILITY ASSAY; NEUTRALIZATION SEROTYPES; GENETIC DIVERSITY; PRIMARY INFECTION; VARIABLE DOMAIN; MOLECULAR CLOCK; DRUG-USERS; SUBTYPE-A; SEQUENCE AB HIV-1 envelope sequence variants were RT-PCR amplified from serum samples cryopreserved in San Francisco in 1978-1979. The HIV-1 subtype B env V3-V5 sequences from four homosexual men clustered phylogenetically, with a median nucleotide distance of 2.8%, reflecting a recent common origin. These early U.S. HIV-1 env variants mapped close to the phylogenetic root of the subtype B tree while env variants collected in the United States throughout the 1980s and 1990s showed, on average, increasing genetic diversity and divergence from the subtype B consensus sequence. These results indicate that the majority of HIV-1 currently circulating in the United States may be descended from an initial introduction and rapid spread during the mid- to late 1970s of subtype B viruses with limited variability (i.e., a founder effect). As expected from the starburst-shaped phylogeny of HIV-1 subtype B, contemporary U.S. strains were, on average, more closely related at the nucleic acid and amino acid levels to the earlier 1978-1979 env variants than to each other. The growing levels of HIV-1 genetic diversity, one of multiple obstacles in designing a protective vaccine, may therefore be mitigated by using epidemic founding variants as antigenic strains for protection against contemporary strains. C1 Univ Calif San Francisco, Blood Ctr Pacific, San Francisco, CA 94118 USA. Rockefeller Univ, Aaron Diamond AIDS Res Ctr, New York, NY 10016 USA. San Francisco Dept Publ Hlth, AIDS Off, San Francisco, CA 94102 USA. Univ Calif San Francisco, Dept Med, San Francisco, CA 94143 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87501 USA. RP Delwart, EL (reprint author), Univ Calif San Francisco, Blood Ctr Pacific, 270 Mason Ave, San Francisco, CA 94118 USA. OI Foley, Brian/0000-0002-1086-0296; Delwart, Eric/0000-0002-6296-4484 FU NIAID NIH HHS [AI40408, AI43895] NR 45 TC 19 Z9 21 U1 5 U2 8 PU MARY ANN LIEBERT INC PUBL PI LARCHMONT PA 2 MADISON AVENUE, LARCHMONT, NY 10538 USA SN 0889-2229 J9 AIDS RES HUM RETROV JI Aids Res. Hum. Retrovir. PD OCT PY 2000 VL 16 IS 15 BP 1463 EP 1469 DI 10.1089/088922200750005985 PG 7 WC Immunology; Infectious Diseases; Virology SC Immunology; Infectious Diseases; Virology GA 365LA UT WOS:000089951700001 PM 11054259 ER PT J AU Selsor, KA Burky, RR Kirner, DL Thomas, JE Southon, JR Taylor, RE AF Selsor, KA Burky, RR Kirner, DL Thomas, JE Southon, JR Taylor, RE TI Late prehistoric petroleum collection in Pennsylvania: Radiocarbon evidence SO AMERICAN ANTIQUITY LA English DT Article ID CALIBRATION AB Previous reports using archaeological, ethnohistoric, a,td historic data have proposed that petroleum was extracted by precontact aboriginal populations in western Pennsylvania employing wood-lined pits. A suite of AMS-based C-14 analyses on total amino acid extracts on nine duplicate samples from a homogenized decadal (10-year) sample of wood wood taken from a single stake removed from a pit feature at Drake Well Park, Titusville, Pennsylvania, has permitted the calibration of a mean C-14 age of 480 +/- 15 B.P. to a 2 sigma (95.4%) confidence interval of A.D. 1415-1440. An early fifteenth-century age for this feature supports the view that petroleum exploitation in this region occurred during Late Woodland times. C1 Univ Calif Riverside, Dept Anthropol, Radiocarbon Lab, Riverside, CA 92521 USA. Mercyhurst Coll, Mercyhurst Archaeol Inst, Erie, PA 16546 USA. Univ Calif Lawrence Livermore Natl Lab, Ctr Accelerator Mass Spectrometry, Livermore, CA 94550 USA. RP Selsor, KA (reprint author), Univ Calif Riverside, Dept Anthropol, Radiocarbon Lab, Riverside, CA 92521 USA. NR 17 TC 1 Z9 1 U1 0 U2 4 PU SOC AMER ARCHAEOLOGY PI WASHINGTON PA 900 SECOND ST., NE STE 12, WASHINGTON, DC 20002-3557 USA SN 0002-7316 J9 AM ANTIQUITY JI Am. Antiq. PD OCT PY 2000 VL 65 IS 4 BP 749 EP 755 DI 10.2307/2694426 PG 7 WC Anthropology; Archaeology SC Anthropology; Archaeology GA 367QT UT WOS:000090073500010 ER PT J AU Ghebranious, N Che, J David, D Fan, Y Zhao, C Marth, G Doktycz, M Weber, JL AF Ghebranious, N Che, J David, D Fan, Y Zhao, C Marth, G Doktycz, M Weber, JL TI Human diallelic insertion/deletion polymorphisms. SO AMERICAN JOURNAL OF HUMAN GENETICS LA English DT Meeting Abstract C1 Marshfield Med Res Fdn, Ctr Med Genet, Marshfield, WI USA. NIH, Natl Lib Med, Natl Ctr Biotechnol Informat, Bethesda, MD USA. Oak Ridge Natl Lab, Div Life Sci, Oak Ridge, TN USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0002-9297 J9 AM J HUM GENET JI Am. J. Hum. Genet. PD OCT PY 2000 VL 67 IS 4 SU 2 MA 124 BP 34 EP 34 PG 1 WC Genetics & Heredity SC Genetics & Heredity GA 355TA UT WOS:000089400700123 ER PT J AU Sloter, E Eskenazi, B Lowe, X Kim, K Hill, F Kidd, S Nath, J Moore II, D Wyrobek, AJ AF Sloter, E Eskenazi, B Lowe, X Kim, K Hill, F Kidd, S Nath, J Moore II, D Wyrobek, AJ TI Sperm aneuploidy and semen quality in a non-clinical cohort of healthy non-smoking men. SO AMERICAN JOURNAL OF HUMAN GENETICS LA English DT Meeting Abstract C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA USA. W Virginia Univ, Morgantown, WV USA. Univ Calif Berkeley, Sch Publ Hlth, Berkeley, CA 94720 USA. Calif Pacific Med Ctr, San Francisco, CA USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0002-9297 J9 AM J HUM GENET JI Am. J. Hum. Genet. PD OCT PY 2000 VL 67 IS 4 SU 2 MA 811 BP 155 EP 155 PG 1 WC Genetics & Heredity SC Genetics & Heredity GA 355TA UT WOS:000089400700814 ER PT J AU Kesterson, RA Nurmi, EL Johnson, DK Sutcliffe, JS AF Kesterson, RA Nurmi, EL Johnson, DK Sutcliffe, JS TI An in situ hybridization-based strategy to detect neuronal patterns of genomic imprinting in the autism candidate region of chromosome 15q11-q13. SO AMERICAN JOURNAL OF HUMAN GENETICS LA English DT Meeting Abstract C1 Vanderbilt Univ, Dept Mol Physiol & Biophys, Nashville, TN 37232 USA. Oak Ridge Natl Lab, Mammalian Genet & Dev Sect, Oak Ridge, TN USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0002-9297 J9 AM J HUM GENET JI Am. J. Hum. Genet. PD OCT PY 2000 VL 67 IS 4 SU 2 MA 873 BP 165 EP 165 PG 1 WC Genetics & Heredity SC Genetics & Heredity GA 355TA UT WOS:000089400700875 ER PT J AU Weier, HU Fung, J Munne, S Lersch, RA Hsieh, HB Chen, XN Korenberg, J Pedersen, RA AF Weier, HU Fung, J Munne, S Lersch, RA Hsieh, HB Chen, XN Korenberg, J Pedersen, RA TI Towards a full karyotype screening of interphase cells: 'FISH and Chip' technology. SO AMERICAN JOURNAL OF HUMAN GENETICS LA English DT Meeting Abstract C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Calif San Francisco, Dept Obstet Gynecol & Reprod Sci, San Francisco, CA 94143 USA. St Barnabas Med Ctr, Livingston, NJ 07052 USA. Univ Calif Los Angeles, Ctr Med Genet Birth Defects, Los Angeles, CA 90048 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0002-9297 J9 AM J HUM GENET JI Am. J. Hum. Genet. PD OCT PY 2000 VL 67 IS 4 SU 2 MA 876 BP 166 EP 166 PG 1 WC Genetics & Heredity SC Genetics & Heredity GA 355TA UT WOS:000089400700877 ER PT J AU Coleman, MA Yin, E Sorensen, K Marsh, BJ Mabery, S Tomascik-Cheeseman, L Liu, S Gregg, JP Mascio-Kegelmeyer, L Attix, T Tucker, J Wyrobek, AJ AF Coleman, MA Yin, E Sorensen, K Marsh, BJ Mabery, S Tomascik-Cheeseman, L Liu, S Gregg, JP Mascio-Kegelmeyer, L Attix, T Tucker, J Wyrobek, AJ TI Radiation-induced changes in the expression of stress response and DNA repair genes in human and mouse cells. SO AMERICAN JOURNAL OF HUMAN GENETICS LA English DT Meeting Abstract C1 Univ Calif Lawrence Livermore Natl Lab, Biol & Biotech Res Prog, Livermore, CA 94551 USA. Univ Calif Davis, Sch Med, Dept Pathol, Sacramento, CA 95817 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0002-9297 J9 AM J HUM GENET JI Am. J. Hum. Genet. PD OCT PY 2000 VL 67 IS 4 SU 2 MA 1019 BP 191 EP 191 PG 1 WC Genetics & Heredity SC Genetics & Heredity GA 355TA UT WOS:000089400701019 ER PT J AU Arking, DE Krebsova, A Macek, M Macek, M Arking, A Mian, IS Fried, LP Hamosh, A Dey, S McIntosh, I Dietz, HC AF Arking, DE Krebsova, A Macek, M Macek, M Arking, A Mian, IS Fried, LP Hamosh, A Dey, S McIntosh, I Dietz, HC TI Mutations in Klotho are associated with survival in diverse human populations. SO AMERICAN JOURNAL OF HUMAN GENETICS LA English DT Meeting Abstract C1 Johns Hopkins Univ, Sch Med, Howard Hughes Med Inst, Baltimore, MD 21205 USA. Johns Hopkins Univ, Sch Med, Inst Med Genet, Baltimore, MD USA. Univ Hosp Motol, Inst Biol & Med Genet, Prague, Czech Republic. Charles Univ, Sch Med 2, Prague, Czech Republic. Johns Hopkins Univ, Baltimore, MD USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Dept Cell & Mol Biol, Berkeley, CA 94720 USA. Johns Hopkins Med Inst, Ctr Aging & Hlth, Baltimore, MD 21205 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0002-9297 J9 AM J HUM GENET JI Am. J. Hum. Genet. PD OCT PY 2000 VL 67 IS 4 SU 2 MA 1231 BP 227 EP 227 PG 1 WC Genetics & Heredity SC Genetics & Heredity GA 355TA UT WOS:000089400701231 ER PT J AU Burmeister, M Puttagunta, R Gordon, LA Meyer, GE Kapfhamer, D Lamerdin, JE Kantheti, P Portman, KM Chung, WK Jenne, DE Olsen, AS AF Burmeister, M Puttagunta, R Gordon, LA Meyer, GE Kapfhamer, D Lamerdin, JE Kantheti, P Portman, KM Chung, WK Jenne, DE Olsen, AS TI Identification of sequences at an evolutionary breakpoint and an inversion through comparative mapping of human 19p13.3 and mouse Chromosome 10. SO AMERICAN JOURNAL OF HUMAN GENETICS LA English DT Meeting Abstract C1 Univ Michigan, Mental Hlth Res Inst, Dept Psychiat, Ann Arbor, MI USA. Univ Michigan, Mental Hlth Res Inst, Dept Human Genet, Ann Arbor, MI USA. Univ Calif Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, Livermore, CA USA. Columbia Univ, New York, NY USA. Max Planck Inst Neurobiol, Martinsried, Germany. RI Burmeister, Margit/A-3157-2013; Puttagunta, Radhika/B-8664-2015 OI Burmeister, Margit/0000-0002-1914-2434; Puttagunta, Radhika/0000-0001-7674-8064 NR 0 TC 0 Z9 0 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0002-9297 J9 AM J HUM GENET JI Am. J. Hum. Genet. PD OCT PY 2000 VL 67 IS 4 SU 2 MA 1416 BP 259 EP 259 PG 1 WC Genetics & Heredity SC Genetics & Heredity GA 355TA UT WOS:000089400701415 ER PT J AU Tomascik-Cheeseman, LM Coleman, MA Mascio-Kegelmeyer, L Marchetti, F Raja, R Nath, J Wyrobek, AJ AF Tomascik-Cheeseman, LM Coleman, MA Mascio-Kegelmeyer, L Marchetti, F Raja, R Nath, J Wyrobek, AJ TI cDNA microarray analyses reveal differential expression of DNA repair-related genes among normal tissues. SO AMERICAN JOURNAL OF HUMAN GENETICS LA English DT Meeting Abstract C1 Univ Calif Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, Livermore, CA USA. W Virginia Univ, Genet & Dev Biol Program, Morgantown, WV 26506 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0002-9297 J9 AM J HUM GENET JI Am. J. Hum. Genet. PD OCT PY 2000 VL 67 IS 4 SU 2 MA 1466 BP 268 EP 268 PG 1 WC Genetics & Heredity SC Genetics & Heredity GA 355TA UT WOS:000089400701467 ER PT J AU Acierno, JS Falardeau, J Kennedy, JC Leyne, M Bromley, MC Colman, M Sun, M Bove, C Bach, G Ashworth, L Schiripo, T Ma, S Helbling, LA Goldin, E Schiffmann, R Slaugenhaupt, SA AF Acierno, JS Falardeau, J Kennedy, JC Leyne, M Bromley, MC Colman, M Sun, M Bove, C Bach, G Ashworth, L Schiripo, T Ma, S Helbling, LA Goldin, E Schiffmann, R Slaugenhaupt, SA TI Precise genetic mapping and haplotype analysis of the Mucolipidosis IV candidate region on human chromosome 19p13.2-13.3. SO AMERICAN JOURNAL OF HUMAN GENETICS LA English DT Meeting Abstract C1 Harvard Univ, Sch Med, Harvard Inst Human Genet, Boston, MA USA. Massachusetts Gen Hosp, Mol Neurogenet Unit, Charlestown, MA USA. NINDS, Dev & Metab Neurol Branch, NIH, Bethesda, MD 20892 USA. Hadassah Univ Hosp, Dept Human Genet, IL-91120 Jerusalem, Israel. Univ Calif Lawrence Livermore Natl Lab, Ctr Human Genome, Livermore, CA USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0002-9297 J9 AM J HUM GENET JI Am. J. Hum. Genet. PD OCT PY 2000 VL 67 IS 4 SU 2 MA 2150 BP 384 EP 384 PG 1 WC Genetics & Heredity SC Genetics & Heredity GA 355TA UT WOS:000089400702151 ER PT J AU Li, W Detter, JC Weiss, HJ Cramer, EM Zhang, Q Novak, EK Favier, R Kingsmore, SF Swank, RT AF Li, W Detter, JC Weiss, HJ Cramer, EM Zhang, Q Novak, EK Favier, R Kingsmore, SF Swank, RT TI Structural organization, transcript expression and mutational analysis of the human Rab geranylgeranyl transferase alpha subunit (RABGGTA) gene. SO AMERICAN JOURNAL OF HUMAN GENETICS LA English DT Meeting Abstract C1 Roswell Pk Canc Inst, Dept Mol & Cellular Biol, Buffalo, NY 14263 USA. DOE Joint Genome Inst, Walnut Creek, CA USA. St Lukes Roosevelt Hosp, Div Hematol Oncol, New York, NY USA. Hop Cochin, Dept Hematol, ICGM, F-75674 Paris, France. Mol Staging Inc, Guilford, CT USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0002-9297 J9 AM J HUM GENET JI Am. J. Hum. Genet. PD OCT PY 2000 VL 67 IS 4 SU 2 MA 2160 BP 385 EP 385 PG 1 WC Genetics & Heredity SC Genetics & Heredity GA 355TA UT WOS:000089400702159 ER PT J AU Sloter, ED Lowe, X Moore, DH Nath, J Wyrobek, AJ AF Sloter, ED Lowe, X Moore, DH Nath, J Wyrobek, AJ TI Multicolor FISH analysis of chromosomal breaks, duplications, deletions, and numerical abnormalities in the sperm of healthy men SO AMERICAN JOURNAL OF HUMAN GENETICS LA English DT Article ID IN-SITU HYBRIDIZATION; FLUORESCENCE INSITU HYBRIDIZATION; TANDEM DNA PROBES; MALE GERM-CELLS; HERITABLE TRANSLOCATIONS; HUMAN-LYMPHOCYTES; 1CEN-1Q12 REGION; DOMINANT LETHAL; MALE-MICE; NONRANDOM DISTRIBUTION AB Transmitted de novo structural chromosomal abnormalities, the majority of which are paternally derived, can lead to abnormal reproductive outcomes as well as genetic diseases in offspring. We developed and validated a new multicolor FISH procedure (sperm ACM, which utilizes DNA probes specific for the alpha [1cen], classical, [1q12], and midi [1p36.3] satellites of chromosome 1) which utilizes DNA probes specific for three regions of chromosome 1 to detect human sperm that carry numerical abnormalities plus two categories of structural, aberrations: (1) duplications and deletions of 1pter and 1cen, and (2) chromosomal. breaks within the 1cen-1q12 region. In healthy men, the average frequencies of sperm with duplications and deletions were (a) 4.5 +/- 0.5 and 4.1 +/- 1.3 per 10(4) involving 1pter and (b) 0.9 +/- 0.4 and 0.8 +/- 0.3 per 104 involving 1cen, respectively. The frequency of sperm exhibiting breaks within the 1cen-1q12 region was 14.1 +/- 1.2 per 10(4). Structural aberrations accounted for 71% of the abnormalities detected by sperm ACM, which was significantly higher than numerical abnormalities (P = 2 x 10(-8)). Our findings also suggest that, for healthy men, (a) sperm carrying postmeiotic chromosomal breaks appear to be more prevalent than those carrying products of premeiotic or meiotic breakage or rearrangements, (b) the high frequency of chromosome breaks measured after "fertilization" by the hamster-egg cytogenetic method already appear to be present and detectable within human sperm by FISH, and (c) there are nonrandom and donor-specific distributions of breakpoint locations within 1q12 in sperm. FISH facilitates the analysis of much larger numbers of sperm than was possible when the hamster-egg method was used. Therefore, FISH-based procedures for simultaneously detecting chromosomal breaks, rearrangements, and numerical abnormalities in sperm may have widespread applications in human genetics, genetic toxicology, and reproductive medicine. C1 Univ Calif Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, Livermore, CA 94550 USA. W Virginia Univ, Genet & Dev Biol Program, Morgantown, WV 26506 USA. Calif Pacific Med Ctr, Res Inst, San Francisco, CA USA. RP Wyrobek, AJ (reprint author), Univ Calif Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, POB 808 L-448, Livermore, CA 94550 USA. FU NIEHS NIH HHS [P42 ES004705, P4ZES04705] NR 82 TC 39 Z9 43 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0002-9297 J9 AM J HUM GENET JI Am. J. Hum. Genet. PD OCT PY 2000 VL 67 IS 4 BP 862 EP 872 DI 10.1086/303088 PG 11 WC Genetics & Heredity SC Genetics & Heredity GA 360DL UT WOS:000089651100010 PM 10961911 ER PT J AU Orfanides, P Buckner, TF Buncick, MC Meriaudeau, F Ferrell, TL AF Orfanides, P Buckner, TF Buncick, MC Meriaudeau, F Ferrell, TL TI Demonstration of surface plasmons in metal island films and the effect of the surrounding medium - An undergraduate experiment SO AMERICAN JOURNAL OF PHYSICS LA English DT Article ID OPTICAL-PROPERTIES; RESONANCE; SPHEROIDS; GOLD AB We present a demonstration of the surface plasmon phenomenon as it occurs in thin metal island films. The metal films are deposited on glass microscope slides. The effect of the surface plasmon resonance may be observed visually on the slide without further apparatus. Heating the film changes the shape of the islands and therefore the resonant frequency of the surface plasmon and changes the color of the film. Placing the film in a dielectric medium changes the resonance condition for the surface plasmon again and changes the color again. We show this by coating the slides with commercially available liquids with different indices of refraction. We present a theoretical model that assumes the islands are oblate spheroids. There are enough details given so that the equations can be programed and the theoretical optical absorbance can be reproduced. We also present a modification to the theory so that the shift in resonant frequency can be calculated when the spheroids are immersed in the index fluids. We describe our apparatus for making thin films and our optical spectrometer system. We then present optical absorbance measurements of thin films of both Ag and Au in air and in two liquids with different indices of refraction. (C) 2000 American Association of Physics Teachers. C1 Memphis State Univ, Dept Phys, Memphis, TN 38152 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Orfanides, P (reprint author), Memphis State Univ, Dept Phys, Memphis, TN 38152 USA. NR 25 TC 21 Z9 22 U1 1 U2 8 PU AMER ASSOC PHYSICS TEACHERS AMER INST PHYSICS PI MELVILLE PA STE 1 NO 1, 2 HUNTINGTON QUADRANGLE, MELVILLE, NY 11747-4502 USA SN 0002-9505 J9 AM J PHYS JI Am. J. Phys. PD OCT PY 2000 VL 68 IS 10 BP 936 EP 942 DI 10.1119/1.1285859 PG 7 WC Education, Scientific Disciplines; Physics, Multidisciplinary SC Education & Educational Research; Physics GA 355UH UT WOS:000089406600008 ER PT J AU Lee, SL Strang, G AF Lee, SL Strang, G TI Row reduction of a matrix and A = CaB SO AMERICAN MATHEMATICAL MONTHLY LA English DT Article C1 Univ Calif Lawrence Livermore Natl Lab, Ctr Appl Sci COmp, Livermore, CA 94551 USA. MIT, Cambridge, MA 02139 USA. RP Lee, SL (reprint author), Univ Calif Lawrence Livermore Natl Lab, Ctr Appl Sci COmp, L-560, Livermore, CA 94551 USA. NR 5 TC 1 Z9 1 U1 0 U2 1 PU MATHEMATICAL ASSOC AMER PI WASHINGTON PA 1529 18TH STREET NW, WASHINGTON, DC 20036 USA SN 0002-9890 J9 AM MATH MON JI Am. Math. Mon. PD OCT PY 2000 VL 107 IS 8 BP 681 EP 688 DI 10.2307/2695466 PG 8 WC Mathematics SC Mathematics GA 362AQ UT WOS:000089756800001 ER PT J AU Hartman, GD Whitaker, JO Munsee, JR AF Hartman, GD Whitaker, JO Munsee, JR TI Diet of the mole scalopus aquaticus from the Coastal Plain region of South Carolina SO AMERICAN MIDLAND NATURALIST LA English DT Article ID LONGEVITY AB We examined the stomach contents of 374 eastern moles (Scalopus aquaticus) collected throughout the year from the Coastal Plain region of South Carolina. On average, stomach contents of males weighed significantly more than did those of females. Fifty-two different food items were recorded. The three most important foods were scarabaeid beetle larvae, ants and centipedes. Earthworms were observed in only 8.3% of the stomachs examined and represented only about 3% of the mean percent volume of the diet. Ants comprised 15.4% of the total volume. Twenty-nine species of ant were recorded; of these, four were taxa not previously reported to occur on the SRS. The imported red fire ant Solenopsis invicta was common within the study area; however, no individuals of this species were found in any of the mole stomachs. C1 McNeese State Univ, Dept Biol & Environm Sci, WAK Seale Vertebrate Museum, Lake Charles, LA 70609 USA. Indiana State Univ, Dept Life Sci, Terre Haute, IN 47809 USA. RP Hartman, GD (reprint author), Savannah River Ecol Lab, Drawer E, Aiken, SC 29802 USA. NR 24 TC 4 Z9 5 U1 0 U2 8 PU AMER MIDLAND NATURALIST PI NOTRE DAME PA UNIV NOTRE DAME, BOX 369, ROOM 295 GLSC, NOTRE DAME, IN 46556 USA SN 0003-0031 J9 AM MIDL NAT JI Am. Midl. Nat. PD OCT PY 2000 VL 144 IS 2 BP 342 EP 351 DI 10.1674/0003-0031(2000)144[0342:DOTMSA]2.0.CO;2 PG 10 WC Biodiversity Conservation; Ecology SC Biodiversity & Conservation; Environmental Sciences & Ecology GA 370HY UT WOS:000165118500011 ER PT J AU Rosso, KM Becker, U Hochella, MF AF Rosso, KM Becker, U Hochella, MF TI Surface defects and self-diffusion on pyrite {100}: An ultra-high vacuum scanning tunneling microscopy and theoretical modeling study SO AMERICAN MINERALOGIST LA English DT Article ID COMPACT EFFECTIVE POTENTIALS; EXPONENT BASIS-SETS; LATTICE-DYNAMICS; FRACTURED PYRITE; 001 SURFACES; OXIDATION; STATES; H2O; SIMULATION; REACTIVITY AB Various defects on {100} cleavage surfaces of pyrite (FeS2) are observed directly using ultra high vacuum scanning tunneling microscopy. Step edges are aligned along [10] and [11] surface directions. Atomic scale images indicate that the atomic structure, with respect to the Fe lattice, and local density of occupied states is unchanged at a step edge, including kink and corner sites. The inferred presence of monosulfides at step edges, based on X-ray photoelectron spectra on similar surfaces elsewhere, does not lead to occupied states higher in energy than d(z2) dangling bond states at Fe sites. A sequence of consecutive images at the atomic scale captured evidence of dynamic structural changes at defects on this surface at room temperature. Step edges appear generally stable over the course of the STM observations, whereas vacancies, their surrounding sites, and corner step edge sites are not. Theoretical maps of the attachment energy for an Fe adatom over a {100} surface cell indicate the presence of low energy diffusion channels along the topology of the closest S atoms in the uppermost atomic S monolayer. Calculation of the activation energy barriers for the self-diffusion of an Fe adatom over a {100} terrace predict low 0.10 eV diffusion barriers along channels and 0.24 eV across channels. Subsequently, calculated Fe adatom mobilities over the time scale of the STM observations are very high, ranging from 10(5)-10(6) Angstrom over the course of one minute, calculated for room temperature and depending on the diffusion direction. The structural changes documented in the STM images are attributed to the natural process of surface self-diffusion. C1 Pacific NW Natl Lab, WR Wiley Environm Mol Sci Lab, Richland, WA 99352 USA. Univ Munster, Inst Mineral, D-48149 Munster, Germany. Virginia Polytech Inst & State Univ, Dept Geol Sci, Blacksburg, VA 24061 USA. RP Rosso, KM (reprint author), Pacific NW Natl Lab, WR Wiley Environm Mol Sci Lab, POB 999,MSIN K8-96, Richland, WA 99352 USA. RI Becker, Udo/F-7339-2011 OI Becker, Udo/0000-0002-1550-0484 NR 29 TC 23 Z9 24 U1 5 U2 16 PU MINERALOGICAL SOC AMER PI WASHINGTON PA 1015 EIGHTEENTH ST, NW SUITE 601, WASHINGTON, DC 20036 USA SN 0003-004X J9 AM MINERAL JI Am. Miner. PD OCT PY 2000 VL 85 IS 10 BP 1428 EP 1436 PG 9 WC Geochemistry & Geophysics; Mineralogy SC Geochemistry & Geophysics; Mineralogy GA 361NJ UT WOS:000089728900011 ER PT J AU Shen, YF Berger, SJ Smith, RD AF Shen, YF Berger, SJ Smith, RD TI Capillary isoelectric focusing of yeast cells SO ANALYTICAL CHEMISTRY LA English DT Article ID HUMAN RHINOVIRUS SEROTYPE-2; ZONE-ELECTROPHORESIS; SURFACE AB In the present work, capillary isoelectric focusing (CIEF) methods were developed for the separation and identification of yeast cells. Yeast cells (similar to 4-mu m diameter) cultured to various phases of growth were shown to be reproducibly resolved by CIEF using 100-mu m-i.d. fused-silica capillaries coated with hydroxypropyl methylcellulose. Separation efficiencies corresponding to peak capacities of >4000 were obtained. The suitable cell concentration range for obtaining repeatable elution in CIEF separations was found to be quite low (<3 cells/mu L). CIEF experiments showed that yeast cell populations at early log, mid log, and stationary growth phases differ in isoelectric point, with values ranging from 5.2 to 6.4. The broader application of CLEF are projected for microorganism identification and separation based upon growth conditions. C1 Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Shen, YF (reprint author), Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RI Smith, Richard/J-3664-2012 OI Smith, Richard/0000-0002-2381-2349 NR 12 TC 60 Z9 62 U1 0 U2 9 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 OCT 1 PY 2000 VL 72 IS 19 BP 4603 EP 4607 DI 10.1021/ac000144w PG 5 WC Chemistry, Analytical SC Chemistry GA 359FL UT WOS:000089600800017 PM 11028617 ER PT J AU Liu, YJ Foote, RS Jacobson, SC Ramsey, RS Ramsey, JM AF Liu, YJ Foote, RS Jacobson, SC Ramsey, RS Ramsey, JM TI Electrophoretic separation of proteins on a microchip with noncovalent, postcolumn labeling SO ANALYTICAL CHEMISTRY LA English DT Article ID CAPILLARY ZONE ELECTROPHORESIS; LASER-INDUCED FLUORESCENCE; OPEN-CHANNEL ELECTROCHROMATOGRAPHY; HUMAN-SERUM; FLUOROMETRIC DETECTION; NANOGRAM LEVELS; AMINO-ACIDS; REACTOR; DERIVATIZATION; CHROMATOGRAPHY AB Proteins were separated by microchip capillary electrophoresis and labeled on-chip by postcolumn addition of a fluorogenic dye, NanoOrange, for detection by laser-induced fluorescence. NanoOrange binds noncovalently with hydrophobic protein regions to form highly fluorescent complexes. Kinetic measurements of complex formation on the microchips suggest that the reaction rate is near the diffusion limit under the conditions used for protein separation. Little or no band broadening is caused by the postcolumn labeling step. Lower limits of detection for model proteins, cc-lactalbumin, P-lactoglobulin A, and beta-lactoglobulin B, were <0.5 pg (similar to 30 amol) of injected sample. The relative fluorescence and reaction rates are compared with those of a number of other fluorogenic dyes used for protein labeling. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Foote, RS (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. FU NCI NIH HHS [CA 83238-02] NR 39 TC 109 Z9 111 U1 3 U2 21 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 OCT 1 PY 2000 VL 72 IS 19 BP 4608 EP 4613 DI 10.1021/ac000625f PG 6 WC Chemistry, Analytical SC Chemistry GA 359FL UT WOS:000089600800018 PM 11028618 ER PT J AU Ma, YF Shortreed, MR Yeung, ES AF Ma, YF Shortreed, MR Yeung, ES TI High-throughput single-molecule spectroscopy in free solution SO ANALYTICAL CHEMISTRY LA English DT Article ID DNA-MOLECULES; FLUORESCENCE SPECTROSCOPY; CONFORMATIONAL DYNAMICS; REAL-TIME; MICROSCOPY; DIFFUSION; IDENTIFICATION; VISUALIZATION; TEMPERATURE; EXCITATION AB A high-speed high-throughput single-molecule imaging technique for identifying molecules in free solution based on differences in their fluorescence emission spectra is presented. Unlike previous reports, the entire spectrum, rather than selected wavelengths through optical filters, is recorded. Furthermore, the millisecond data acquisition time means that the molecules do not need to be immobilized or spatially confined. In one example, individual lambda DNA molecules labeled with YOYO-I, POPO-III, or a combination of the two dyes can be distinguished from one another. In another example, biotinylated 2.1-kb DNA labeled with YOYO-I was reacted with avidin-conjugated R-phycoerythrin. The two different reactant molecules and the product molecule can be simultaneously imaged and identified by their spectroscopic characteristics. This technique can therefore be used for screening single molecules for disease markers and for monitoring individual molecular interactions at a rate of thousands of molecules per second. C1 Iowa State Univ, USDOE, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Chem, Ames, IA 50011 USA. RP Yeung, ES (reprint author), Iowa State Univ, USDOE, Ames Lab, Ames, IA 50011 USA. NR 55 TC 73 Z9 74 U1 1 U2 9 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 OCT 1 PY 2000 VL 72 IS 19 BP 4640 EP 4645 DI 10.1021/ac000584n PG 6 WC Chemistry, Analytical SC Chemistry GA 359FL UT WOS:000089600800023 PM 11028623 ER PT J AU Collins, B Wein, G AF Collins, B Wein, G TI Stem elongation response to neighbour shade in sprawling and upright Polygonum species SO ANNALS OF BOTANY LA English DT Article DE neighbour effects; light variation; red : far-red; plant growth strategy; Polygonum sagittatum; Polygonum hydropiperoides; smartweeds ID ADAPTIVE PLASTICITY HYPOTHESIS; FAR-RED RATIO; IMPATIENS-CAPENSIS; LIGHT QUALITY; MARSH PLANTS; FLUENCE RATE; PHYTOCHROME; GROWTH; COMPETITION; ALLOCATION AB Shading by neighbouring plants, which reduces energy for photosynthesis and lowers the ratio of red:far red light, can trigger a stem elongation or 'overtopping' response in herbaceous plants. We compared the stem elongation response of two Polygomum species in a greenhouse experiment. P. sagittatum, a sprawling, vine-like annual, and P. hydropiperoides, an upright perennial, were grown from seeds at three levels of neighbour shade produced by crowding a cohort of real neighbour plants or adult-sized fake neighbour plants that provided shade and reduced the red:far-red ratio. We hypothesized that the annual would show a more pronounced elongation response to developing or adult neighbour shade because vine-like plants are less mechanically constrained to remain upright and self-supporting. Internodes on stems of both P. sagittatum and P. hydropiperoides increased in length as the amount of shading by real of fake neighbours increased. P. sagittatum climbed on adjacent plants, and had longer stems with more nodes than those of P. hydropiperoides. Although both P. sagittatum and P. hydropiperoides tended to elongate with crowding, the greater elongation response to both real and fake neighbours shown by the sprawling annual reflects its ability to extend upward into a canopy beyond self-supporting height. Self-supporting P. hydropiperoides can extend upward with, or overtop, cohort neighbours, but might less readily elongate into an extant canopy. In dense stands, P. sagittatum can become structurally dependent on close P. hydropiperoides neighbours. Our results suggest that the elongation response of P. sagittatum to neighbours can contribute to structural dependence and could facilitate coexistence of these species. (C) 2000 Annals of Botany Company. C1 Savannah River Ecol Lab, Aiken, SC 29802 USA. RP Collins, B (reprint author), Savannah River Ecol Lab, PO Drawer E, Aiken, SC 29802 USA. NR 32 TC 11 Z9 20 U1 0 U2 4 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0305-7364 J9 ANN BOT-LONDON JI Ann. Bot. PD OCT PY 2000 VL 86 IS 4 BP 739 EP 744 DI 10.1006/anbo.2000.1233 PG 6 WC Plant Sciences SC Plant Sciences GA 359EY UT WOS:000089599600005 ER PT J AU Fuller, ME Streger, SH Rothmel, RK Mailloux, BJ Hall, JA Onstott, TC Fredrickson, JK Balkwill, DL DeFlaun, MF AF Fuller, ME Streger, SH Rothmel, RK Mailloux, BJ Hall, JA Onstott, TC Fredrickson, JK Balkwill, DL DeFlaun, MF TI Development of a vital fluorescent staining method for monitoring bacterial transport in subsurface environments SO APPLIED AND ENVIRONMENTAL MICROBIOLOGY LA English DT Article ID 5-CYANO-2,3-DITOLYL TETRAZOLIUM CHLORIDE; POLYMERASE-CHAIN-REACTION; PSEUDOMONAS-FLUORESCENS; ESCHERICHIA-COLI; SANDY AQUIFER; RESPIRATORY ACTIVITY; RESPIRING BACTERIA; QUANTITATIVE PCR; SCALE EVALUATION; SOLID-SURFACES AB Previous bacterial transport studies have utilized fluorophores which have been shown to adversely affect the physiology of stained cells. This research was undertaken to identify alternative fluorescent stains that do not adversely affect the transport or viability of bacteria. Initial work was performed with a groundwater isolate, Comamonas sp. strain DA001, Potential compounds were first screened to determine staining efficiencies and adverse side effects. 5-(And 6-)-carboxyfluorescein diacetate, succinimidyl ester (CFDA/SE) efficiently stained DA001 without causing undesirable effects on cell adhesion or viability. Members of many other gram-negative and gram-positive bacterial genera were also effectively stained with CFDA/SE. More than 95% of CFDA/SE-stained Comamonas sp. strain DA001 cells incubated in artificial groundwater (under no-growth conditions) remained fluorescent for at least 28 days as determined by epifluorescent microscopy and flow cytometry. No differences in the survival and culturability of CFDA/SE-stained and unstained DA001 cells in groundwater or saturated sediment microcosms were detected. The bright, yellow-green cells were readily distinguished from autofluorescing sediment particles try epifluorescence microscopy, A high throughput method using microplate spectrofluorometry was developed, which had a detection limit of mid-10(5) CFDA-stained cells/ml; the detection limit for flow cytometry was on the order of 1,000 cells/ml. The results of laboratory-scale bacterial transport experiments performed with intact sediment cores and nondividing DA001 cells revealed good agreement between the aqueous cell concentrations determined by the microplate assay and those determined by other enumeration methods. This research indicates that CFDA/SE is very efficient for labeling cells for bacterial transport experiments and that it may be useful for other microbial ecology research as well. C1 Envirogen Inc, Princeton Res Ctr, Lawrenceville, NJ 08648 USA. Princeton Univ, Dept Geosci, Princeton, NJ 08544 USA. Pacific NW Natl Lab, Richland, WA 99338 USA. Florida State Univ, Dept Biol Sci, Tallahassee, FL 32306 USA. RP Fuller, ME (reprint author), Envirogen Inc, Princeton Res Ctr, 4100 Quakerbridge Rd, Lawrenceville, NJ 08648 USA. NR 55 TC 71 Z9 72 U1 3 U2 23 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1752 N ST NW, WASHINGTON, DC 20036-2904 USA SN 0099-2240 J9 APPL ENVIRON MICROB JI Appl. Environ. Microbiol. PD OCT PY 2000 VL 66 IS 10 BP 4486 EP 4496 DI 10.1128/AEM.66.10.4486-4496.2000 PG 11 WC Biotechnology & Applied Microbiology; Microbiology SC Biotechnology & Applied Microbiology; Microbiology GA 360CW UT WOS:000089649700048 PM 11010903 ER PT J AU Nold, SC Zhou, JZ Devol, AH Tiedje, JM AF Nold, SC Zhou, JZ Devol, AH Tiedje, JM TI Pacific northwest marine sediments contain ammonia-oxidizing bacteria in the beta subdivision of the Proteobacteria SO APPLIED AND ENVIRONMENTAL MICROBIOLOGY LA English DT Article ID 16S RIBOSOMAL-RNA; PARTICULATE METHANE MONOOXYGENASE; GENE-SEQUENCES; FRESH; WATER; POPULATIONS; METHANOTROPHS; ECOLOGY; LAKES; SOIL AB The diversity of ammonia-oxidizing bacteria in aquatic sediments was studied by retrieving ammonia monooxygenase and methane monooxygenase gene sequences. Methanotrophs dominated freshwater sediments, while beta-proteobacterial ammonia oxidizers dominated marine sediments. These results suggest that gamma-proteobacteria such as Nitrosococcus oceani are minor members of marine sediment ammonia-oxidizing communities. C1 Michigan State Univ, Ctr Microbial Ecol, E Lansing, MI 48824 USA. Michigan State Univ, Dept Crop & Soil Sci, E Lansing, MI 48824 USA. Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. Univ Washington, Sch Oceanog, Seattle, WA 98295 USA. RP Nold, SC (reprint author), Univ Wisconsin Stout, Dept Biol, Menomonic, WI 54751 USA. NR 21 TC 75 Z9 85 U1 0 U2 8 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1752 N ST NW, WASHINGTON, DC 20036-2904 USA SN 0099-2240 J9 APPL ENVIRON MICROB JI Appl. Environ. Microbiol. PD OCT PY 2000 VL 66 IS 10 BP 4532 EP 4535 DI 10.1128/AEM.66.10.4532-4535.2000 PG 4 WC Biotechnology & Applied Microbiology; Microbiology SC Biotechnology & Applied Microbiology; Microbiology GA 360CW UT WOS:000089649700056 PM 11010911 ER PT J AU Mayer, JRR Phan, AV Cloutier, G AF Mayer, JRR Phan, AV Cloutier, G TI Prediction of diameter errors in bar turning: a computationally effective model SO APPLIED MATHEMATICAL MODELLING LA English DT Article DE turning simulation; finite element model; dimensional errors; deflections of machining systems AB Machining accuracy can be considerably affected by the deflections of the machine-workpiece-tool system as well as the thermal expansion of material during machining. An improved model for predicting dimensional errors in turning process is presented. This model uses a geometric analysis in the machine frame, in which the elastic deflections of the machine-workpiece-tool system due to the cutting force are studied. In this paper, our workpiece deflection model [A.-V. Phan, G. Cloutier, J.R.R. Mayer, International Journal of Production Research 37 (1999) 4039-4051; G. Cloutier, J.R.R. Mayer, A.-V. Phan, Computer Modeling and Simulation in Engineering 4 (1999) 133-137] earlier developed is employed. As described in Phan et al. (1999), this deflection model is general, accurate and computationally effective thanks to its closed-form solutions derived from the finite element technique. Also, due to the coupling between the cutting force and actual depth of cut, iterative computations are performed to obtain the coupling value of this force which provides further accuracy to the prediction. Finally, via numerical examples, the predicted diameter error on a workpiece, the ratio between the coupled cutting force and its nominal value along the part axis as well as the influence of the cutting force components on the error prediction are computed using the proposed model. The results provide additional insight into the error formation in the turning process. (C) 2000 Elsevier Science Inc. All rights reserved. C1 Ecole Polytech, Dept Mech Engn, Montreal, PQ H3C 3A7, Canada. RP Phan, AV (reprint author), Oak Ridge Natl Lab, Div Math & Comp Sci, POB 2008,Bld 6012, Oak Ridge, TN 37831 USA. NR 10 TC 23 Z9 26 U1 0 U2 2 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0307-904X J9 APPL MATH MODEL JI Appl. Math. Model. PD OCT PY 2000 VL 24 IS 12 BP 943 EP 956 DI 10.1016/S0307-904X(00)00027-5 PG 14 WC Engineering, Multidisciplinary; Mathematics, Interdisciplinary Applications; Mechanics SC Engineering; Mathematics; Mechanics GA 356CR UT WOS:000089427200006 ER PT J AU Dulloo, AR Ruddy, FH Congedo, TV Seidel, JG McIlwain, ME AF Dulloo, AR Ruddy, FH Congedo, TV Seidel, JG McIlwain, ME TI Experimental verification of modeling results for a PGNAA system for nondestructive assay of RCRA metals in drums SO APPLIED RADIATION AND ISOTOPES LA English DT Article; Proceedings Paper CT 4th Topical Meeting on the Industrial Radiation and Radioisotope Measurement Applications (IRRMA 99) CY OCT 03-07, 1999 CL RALEIGH, NORTH CAROLINA SP Amer Nuclear Soc, Isotopes & Radiat Div, Amer Nuclear Soc, Eastern Carolinas Sect, N Carolina State Univ, Ctr Engn Applicat Radioisotopes, Quantum Res Serv Inc DE prompt; gamma; neutron; metals; NDA AB The use of pulsed gamma neutron activation analysis (PGNAA) for the nondestructive assay of mercury, cadmium and lead in a concrete matrix has been demonstrated. Calculations have also been performed to study interference with PGNAA detection sensitivity resulting from the presence of U-138, U-235, and Pu-239 at levels expected in mixed waste. Analyses based on transport calculations examined the effects of these nuclides on neutron kinetics, and the contribution from the capture, fission and decay gamma-rays emitted by the nuclides to the gamma-ray spectrum. These calculations predicted insignificant effects on the system's detection limits (115, 9 and 4400 ppm for Hg, Cd and Pb, respectively, for a 2000 s assay). This paper describes verification measurements recently conducted using samples of U-235 and U-238 in the test drum geometry, which have provided experimental confirmation of the modeling results. (C) 2000 Elsevier Science Ltd. All rights reserved. C1 Westinghouse Sci & Technol Ctr, Pittsburgh, PA 15235 USA. Lockheed Martin Idaho Technol, Idaho Falls, ID USA. RP Dulloo, AR (reprint author), Westinghouse Sci & Technol Ctr, Pittsburgh, PA 15235 USA. NR 3 TC 5 Z9 5 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0969-8043 J9 APPL RADIAT ISOTOPES JI Appl. Radiat. Isot. PD OCT-NOV PY 2000 VL 53 IS 4-5 BP 499 EP 505 DI 10.1016/S0969-8043(00)00201-3 PG 7 WC Chemistry, Inorganic & Nuclear; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Chemistry; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 345TE UT WOS:000088830600003 ER PT J AU Molnar, GL Revay, Z Belgya, T Firestone, RB AF Molnar, GL Revay, Z Belgya, T Firestone, RB TI The new prompt gamma-ray catalogue for PGAA SO APPLIED RADIATION AND ISOTOPES LA English DT Article; Proceedings Paper CT 4th Topical Meeting on the Industrial Radiation and Radioisotope Measurement Applications (IRRMA 99) CY OCT 03-07, 1999 CL RALEIGH, NORTH CAROLINA SP Amer Nuclear Soc, Isotopes & Radiat Div, Amer Nuclear Soc, Eastern Carolinas Sect, N Carolina State Univ, Ctr Engn Applicat Radioisotopes, Quantum Res Serv Inc DE prompt gamma ray; PGAA; neutron capture; gamma-ray energy; production cross-section ID ACTIVATION-ANALYSIS; BUDAPEST AB A new catalogue of subthermal neutron-induced prompt gamma rays has been created for 79 elements, from hydrogen to uranium (including fission), on the basis of recent measurements at the Budapest guided-neutron PGAA facility. New energy values have been measured using Cl-35 neutron-capture gamma rays, while the gamma-ray production cross-sections have been determined with respect to the H-1 thermal capture cross-section. The elemental data have been compared with thermal neutron-capture data for individual nuclides from the Evaluated Nuclear Structure Data File, ENSDF, hence isotope identifications could be made. The catalogue contains elemental spectra and a table with nearly 7000 gamma rays with relative intensity over 1% of the strongest line. The average accuracy is about 0.08 keV for energies and about 5% for cross-sections in the whole energy range, from about 40 keV to 11 MeV. (C) 2000 Elsevier Science Ltd. All rights reserved. C1 Hungarian Acad Sci, Chem Res Ctr, Inst Isotope & Surface Chem, H-1525 Budapest, Hungary. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. RP Molnar, GL (reprint author), Hungarian Acad Sci, Chem Res Ctr, Inst Isotope & Surface Chem, H-1525 Budapest, Hungary. OI Firestone, Richard/0000-0003-3833-5546 NR 20 TC 20 Z9 22 U1 1 U2 9 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0969-8043 J9 APPL RADIAT ISOTOPES JI Appl. Radiat. Isot. PD OCT-NOV PY 2000 VL 53 IS 4-5 BP 527 EP 533 DI 10.1016/S0969-8043(00)00209-8 PG 7 WC Chemistry, Inorganic & Nuclear; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Chemistry; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 345TE UT WOS:000088830600006 ER PT J AU Burr, TL Knepper, PL AF Burr, TL Knepper, PL TI A study of the effect of measurement error in predictor variables in nondestructive assay SO APPLIED RADIATION AND ISOTOPES LA English DT Article; Proceedings Paper CT 4th Topical Meeting on the Industrial Radiation and Radioisotope Measurement Applications (IRRMA 99) CY OCT 03-07, 1999 CL RALEIGH, NORTH CAROLINA SP Amer Nuclear Soc, Isotopes & Radiat Div, Amer Nuclear Soc, Eastern Carolinas Sect, N Carolina State Univ, Ctr Engn Applicat Radioisotopes, Quantum Res Serv Inc DE errors in predictors; nondestructive assay (NDA) ID REGRESSION AB It is not widely known that ordinary least squares estimates exhibit bias if there are errors in the predictor variables. For example, enrichment measurements are often fit to two predictors: Poisson-distributed count rates in the region of interest and in the background. Both count rates have at least random variation due to counting statistics. Therefore, the parameter estimates will be biased. In this case, the effect of bias is a minor issue because there is almost no interest in the parameters themselves. Instead, the parameters will be used to convert count rates into estimated enrichment. In other cases, this bias source is potentially more important. For example, in tomographic gamma scanning, there is an emission stage which depends on predictors (the "system matrix") that are estimated with error during the transmission stage. In this paper, we (1) provide background information for the impact and treatment of errors in predictors, (2) present results of candidate methods of compensating for the effect, (3) review some of the nondestructive assay situations where errors in predictors occurs, and (4) provide guidance for when errors in predictors should be considered in nondestructive assay. (C) 2000 Elsevier Science Ltd. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Burr, TL (reprint author), Univ Calif Los Alamos Natl Lab, Mail Stop E541, Los Alamos, NM 87545 USA. NR 12 TC 8 Z9 8 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0969-8043 J9 APPL RADIAT ISOTOPES JI Appl. Radiat. Isot. PD OCT-NOV PY 2000 VL 53 IS 4-5 BP 547 EP 555 DI 10.1016/S0969-8043(00)00216-5 PG 9 WC Chemistry, Inorganic & Nuclear; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Chemistry; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 345TE UT WOS:000088830600009 ER PT J AU Earnhart, J Prettyman, T Lestone, J Gardner, R AF Earnhart, J Prettyman, T Lestone, J Gardner, R TI Simulation of Compton camera imaging with a specific purpose Monte Carlo code SO APPLIED RADIATION AND ISOTOPES LA English DT Article; Proceedings Paper CT 4th Topical Meeting on the Industrial Radiation and Radioisotope Measurement Applications (IRRMA 99) CY OCT 03-07, 1999 CL RALEIGH, NORTH CAROLINA SP Amer Nuclear Soc, Isotopes & Radiat Div, Amer Nuclear Soc, Eastern Carolinas Sect, N Carolina State Univ, Ctr Engn Applicat Radioisotopes, Quantum Res Serv Inc DE Monte Carlo; Compton camera; gamma-ray imaging AB A specific purpose Monte Carlo model that treats the physical processes of image formation in Compton cameras is presented. Features of the model include: detailed Compton scattering physics, including incoherent scattering functions and Doppler broadening; multiple scattering; and peak detector response functions. Calculation efficiency is enhanced by making every history result in a partial success through the extensive use of pathway sampling variance reduction techniques. The code was benchmarked to data obtained from a prototype camera using CdZnTe and silicon room-temperature detector technology. Reasons for observed discrepancies between the simulation model and experiments are explored. Implicit assumptions, related to our implementation of pathway sampling, appear to be the greatest source of error. (C) 2000 Elsevier Science Ltd. All rights reserved. C1 N Carolina State Univ, Dept Nucl Engn, Ctr Engn Applicat Radioisotopes, Raleigh, NC 27695 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87544 USA. RP Earnhart, J (reprint author), N Carolina State Univ, Dept Nucl Engn, Ctr Engn Applicat Radioisotopes, Box 7909, Raleigh, NC 27695 USA. OI Prettyman, Thomas/0000-0003-0072-2831 NR 14 TC 4 Z9 4 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0969-8043 J9 APPL RADIAT ISOTOPES JI Appl. Radiat. Isot. PD OCT-NOV PY 2000 VL 53 IS 4-5 BP 673 EP 680 DI 10.1016/S0969-8043(00)00203-7 PG 8 WC Chemistry, Inorganic & Nuclear; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Chemistry; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 345TE UT WOS:000088830600025 ER PT J AU dos Santos, JMF Monteiro, CMB Morgado, RE Conde, CAN AF dos Santos, JMF Monteiro, CMB Morgado, RE Conde, CAN TI Energy linearity of high-purity germanium detectors in the region of the GeK-absorption edge: experimental results SO APPLIED RADIATION AND ISOTOPES LA English DT Article; Proceedings Paper CT 4th Topical Meeting on the Industrial Radiation and Radioisotope Measurement Applications (IRRMA 99) CY OCT 03-07, 1999 CL RALEIGH, NORTH CAROLINA SP Amer Nuclear Soc, Isotopes & Radiat Div, Amer Nuclear Soc, Eastern Carolinas Sect, N Carolina State Univ, Ctr Engn Applicat Radioisotopes, Quantum Res Serv Inc DE HPGe; energy linearity; K-edge ID XENON RADIATION DETECTORS; PROPORTIONAL COUNTER; X-RAYS; NONLINEARITY; SIMULATION; SILICON AB Non-linearities in the energy response of gas detectors in the regions of the absorption edges of the detection medium are well documented. Monte Carlo calculations show that the non-linearity results from differences in efficiencies for converting absorbed radiation into ionisation for different atomic sub-shells. Energy non-linearity in germanium-based solid-state detectors in the region of the germanium 11.104-keV K-edge is not well documented, although a 1% non-linearity has been previously reported in a Ge(Li) detector. This relatively high value is of practical concern since high-purity germanium (HPGe) is often the detector of choice for alpha- and X-ray spectrometry down to a few keV. In this paper, we present the experimental results for the energy response of a HPGe detector in the 8-15-keV energy region of the germanium K-edge. Within the accuracy of our measurements, we conclude that there is no measurable non-linearity effect in germanium at the K-edge. (C) 2000 Elsevier Science Ltd. All rights reserved. C1 Univ Coimbra, Dept Phys, P-3000 Coimbra, Portugal. Univ Calif Los Alamos Natl Lab, Los Alamos, NM USA. RP dos Santos, JMF (reprint author), Univ Coimbra, Dept Phys, P-3000 Coimbra, Portugal. RI dos Santos, Joaquim/B-3058-2015; OI Monteiro, Cristina Maria Bernardes/0000-0002-1912-2804; Conde, Carlos/0000-0002-1387-2161; dos Santos, Joaquim Marques Ferreira/0000-0002-8841-6523 NR 13 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 0969-8043 J9 APPL RADIAT ISOTOPES JI Appl. Radiat. Isot. PD OCT-NOV PY 2000 VL 53 IS 4-5 BP 739 EP 743 DI 10.1016/S0969-8043(00)00225-6 PG 5 WC Chemistry, Inorganic & Nuclear; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Chemistry; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 345TE UT WOS:000088830600033 ER PT J AU Wallace, SA Hiller, JM Dai, S Miller, LF AF Wallace, SA Hiller, JM Dai, S Miller, LF TI Neutron detection based upon a lithiated sol-gel glass SO APPLIED RADIATION AND ISOTOPES LA English DT Article; Proceedings Paper CT 4th Topical Meeting on the Industrial Radiation and Radioisotope Measurement Applications (IRRMA 99) CY OCT 03-07, 1999 CL RALEIGH, NORTH CAROLINA SP Amer Nuclear Soc, Isotopes & Radiat Div, Amer Nuclear Soc, Eastern Carolinas Sect, N Carolina State Univ, Ctr Engn Applicat Radioisotopes, Quantum Res Serv Inc DE neutron detector; sol-gel dopants; fission particle detector; lithiated glass ID URANYL ADSORPTION AB The addition of dopants in the wet chemistry formation of glass in sol-gel technology is used for many purposes. Among the uses are the fabrication of films sensitive to pH, temperature, the presence of dissolved chemicals in solutions and many others. This paper describes the use of sol-gel technology for the doping of B-10, Li-6 and U-235 into glass films applied to silicon surface barrier (SSB) detectors. Using a commercial preamp/amplifier and an IEEE-488 NIM counter, the response was recorded of the neutron profile in a neutron activation source. A portable personal computer recorded the thermal neutron map as the detector was lowered in 1.27-cm steps down a Numec thermal neutron activation source. The lithiated glass film on the SSB gave about four times the count rate of the boron-10 doped glass film. The U-235 doped glass film gave a much lower count rate, but maintained a constant output signal due to the presence of the alpha activity from the U-235 and the trace of U-234 present in the sample. (C) 2000 Elsevier Science Ltd. All rights reserved. C1 Univ Tennessee, Dept Nucl Engn, Knoxville, TN 37996 USA. Oak Ridge Y12 Plant, Dev Div, Oak Ridge, TN 37831 USA. Oak Ridge Natl Lab, Div Chem Technol, Oak Ridge, TN 37831 USA. RP Wallace, SA (reprint author), Univ Tennessee, Dept Nucl Engn, Knoxville, TN 37996 USA. RI Dai, Sheng/K-8411-2015 OI Dai, Sheng/0000-0002-8046-3931 NR 13 TC 2 Z9 2 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0969-8043 J9 APPL RADIAT ISOTOPES JI Appl. Radiat. Isot. PD OCT-NOV PY 2000 VL 53 IS 4-5 BP 755 EP 758 DI 10.1016/S0969-8043(00)00222-0 PG 4 WC Chemistry, Inorganic & Nuclear; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Chemistry; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 345TE UT WOS:000088830600035 ER PT J AU Martin, RC Knauer, JB Balo, PA AF Martin, RC Knauer, JB Balo, PA TI Production, distribution and applications of californium-252 neutron sources SO APPLIED RADIATION AND ISOTOPES LA English DT Article; Proceedings Paper CT 4th Topical Meeting on the Industrial Radiation and Radioisotope Measurement Applications (IRRMA 99) CY OCT 03-07, 1999 CL RALEIGH, NC SP Amer Nuclear Soc, Isotopes & Radiat Div, Amer Nuclear Soc, Eastern Carolinas Sect, N Carolina State Univ, Ctr Engn Applicat Radioisotopes, Quantum Res Serv Inc DE californium; (252)Cf; neutron; irradiation ID CF-252 AB The radioisotope (252)Cf is routinely encapsulated into compact, portable, intense neutron sources with a 2.6-yr half-life. A source the size of a person's little finger can emit up to 10(11) neutrons s(-1). Californium-252 is used commercially as a reliable, cost-effective neutron source for prompt gamma neutron activation analysis (PGNAA) of coal, cement and minerals, as well as for detection and identification of explosives, land mines and unexploded military ordnance. Other uses are neutron radiography, nuclear waste assays, reactor start-up sources, calibration standards and cancer therapy. The inherent safety of source encapsulations is demonstrated by 30 yr of experience and by US Bureau of Mines tests of source survivability during explosions. The production and distribution center for the US Department of Energy (DOE) Californium Program is the Radiochemical Engineering Development Center (REDC) at Oak Ridge National Laboratory (ORNL), DOE sells (252)Cf to commercial reencapsulators domestically and internationally. Sealed (252)Cf sources are also available for loan to agencies and subcontractors of the US government and to universities for educational, research and medical applications. The REDC has established the Califoinium User Facility (CUF) for Neutron Science to make its large inventory of (252)Cf sources available to researchers for irradiations inside uncontaminated hot cells. Experiments at the CUF include a land mine detection system, neutron damage testing of solid-state detectors, irradiation of human cancer cells for boron neutron capture therapy experiments and irradiation of rice to induce genetic mutations. (C) 2000 Elsevier Science Ltd. All rights reserved. C1 Oak Ridge Natl Lab, Div Chem Technol, Oak Ridge, TN 37831 USA. RP Martin, RC (reprint author), Oak Ridge Natl Lab, Div Chem Technol, Oak Ridge, TN 37831 USA. EM martinrc@ornl.gov RI huang, hongqi/N-1473-2014 NR 11 TC 25 Z9 28 U1 1 U2 9 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0969-8043 J9 APPL RADIAT ISOTOPES JI Appl. Radiat. Isot. PD OCT-NOV PY 2000 VL 53 IS 4-5 BP 785 EP 792 DI 10.1016/S0969-8043(00)00214-1 PG 8 WC Chemistry, Inorganic & Nuclear; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Chemistry; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 345TE UT WOS:000088830600040 PM 11003521 ER PT J AU Verbeke, JM Leung, KN Vujic, J AF Verbeke, JM Leung, KN Vujic, J TI Development of a sealed-accelerator-tube neutron generator SO APPLIED RADIATION AND ISOTOPES LA English DT Article; Proceedings Paper CT 4th Topical Meeting on the Industrial Radiation and Radioisotope Measurement Applications (IRRMA 99) CY OCT 03-07, 1999 CL RALEIGH, NORTH CAROLINA SP Amer Nuclear Soc, Isotopes & Radiat Div, Amer Nuclear Soc, Eastern Carolinas Sect, N Carolina State Univ, Ctr Engn Applicat Radioisotopes, Quantum Res Serv Inc DE neutron generator; D-T neutron source; solid target neutron yield ID DRIVEN AB Sealed-accelerator-tube neutron generators are being developed in Lawrence Berkeley National Laboratory (LBNL) for applications ranging from neutron radiography to boron neutron capture therapy and neutron activation analysis. The new generation of high-output neutron generators is based on the D-T fusion reaction, producing 14.1-MeV neutrons. The main components of the neutron tube - the ion source, the accelerator and the target - are all housed in a sealed metal container without external pumping. Thick-target neutron yield computations are performed in this paper to estimate the neutron yield of titanium and scandium targets. With an average deuteron beam current of 1 A and an energy of 120 keV, a time-averaged neutron production of similar to 10(14) n/s can be estimated for a tritiated target, for both pulsed and cw operations. In mixed deuteron/triton beam operation, a beam current of 2 A at 150 keV is required for the same neutron output. Recent experimental results on ion sources and accelerator columns are presented and discussed. Published by Elsevier Science Ltd. C1 Univ Calif Berkeley, Dept Nucl Engn, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Verbeke, JM (reprint author), Univ Calif Berkeley, Dept Nucl Engn, Berkeley, CA 94720 USA. NR 10 TC 37 Z9 46 U1 0 U2 6 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0969-8043 J9 APPL RADIAT ISOTOPES JI Appl. Radiat. Isot. PD OCT-NOV PY 2000 VL 53 IS 4-5 BP 801 EP 809 DI 10.1016/S0969-8043(00)00262-1 PG 9 WC Chemistry, Inorganic & Nuclear; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Chemistry; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 345TE UT WOS:000088830600042 ER PT J AU Hendricks, JS Adams, KJ Booth, TE Briesmeister, JF Carter, LL Cox, LJ Favorite, JA Forster, RA McKinney, GW Prael, RE AF Hendricks, JS Adams, KJ Booth, TE Briesmeister, JF Carter, LL Cox, LJ Favorite, JA Forster, RA McKinney, GW Prael, RE TI Present and future capabilities of MCNP SO APPLIED RADIATION AND ISOTOPES LA English DT Article; Proceedings Paper CT 4th Topical Meeting on the Industrial Radiation and Radioisotope Measurement Applications (IRRMA 99) CY OCT 03-07, 1999 CL RALEIGH, NORTH CAROLINA SP Amer Nuclear Soc, Isotopes & Radiat Div, Amer Nuclear Soc, Eastern Carolinas Sect, N Carolina State Univ, Ctr Engn Applicat Radioisotopes, Quantum Res Serv Inc AB Several new capabilities have been added to MCNP4C including: (1) macrobody surfaces; (2) the superimposed mesh importance functions, so that it is no longer necessary to subdivide geometries for variance reduction; and (3) Xlib graphics and DVF Fortran 90 for PCs. There are also improvements in neutron physics, electron physics, perturbations, and parallelization. In the more distant future we are working on adaptive Monte Carlo code modernization, more parallelization, visualization, and charged particles. Published by Elsevier Science Ltd. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87544 USA. Carter Monte Carlo Anal, Keizer, OR 97303 USA. RP Hendricks, JS (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663,X-CI,MS F663, Los Alamos, NM 87544 USA. NR 22 TC 12 Z9 13 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0969-8043 J9 APPL RADIAT ISOTOPES JI Appl. Radiat. Isot. PD OCT-NOV PY 2000 VL 53 IS 4-5 BP 857 EP 861 DI 10.1016/S0969-8043(00)00231-1 PG 5 WC Chemistry, Inorganic & Nuclear; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Chemistry; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 345TE UT WOS:000088830600050 ER PT J AU Emmett, MB AF Emmett, MB TI MORSE: present capabilities and future directions SO APPLIED RADIATION AND ISOTOPES LA English DT Article; Proceedings Paper CT 4th Topical Meeting on the Industrial Radiation and Radioisotope Measurement Applications (IRRMA 99) CY OCT 03-07, 1999 CL RALEIGH, NORTH CAROLINA SP Amer Nuclear Soc, Isotopes & Radiat Div, Amer Nuclear Soc, Eastern Carolinas Sect, N Carolina State Univ, Ctr Engn Applicat Radioisotopes, Quantum Res Serv Inc DE Monte Carlo; radiation transport; MORSE AB The MORSE (Multigroup Oak Ridge Stochastic Experiment) Monte Carlo code is a three-dimensional (3D) multipurpose neutron and gamma-ray transport code that has been in use for nearly 30 years and has undergone several evolutions during that time. This article will describe the current capabilities and the future directions of the two versions that are distributed by Oak Ridge National Laboratory: MORSE-SGC and MORSE-CGA. MORSE-SGC is part of the SCALE computer code system, both as a stand-alone program and as part of two of the shielding analysis sequences. MORSE-CGA differs from MORSE-SGC in its cross-section handling and in its requirement for user-supplied analysis routines. (C) 2000 Elsevier Science Ltd. All rights reserved. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Emmett, MB (reprint author), Oak Ridge Natl Lab, POB 2008,MS 6370,Bethel Valley Rd, Oak Ridge, TN 37831 USA. NR 2 TC 2 Z9 2 U1 1 U2 2 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0969-8043 J9 APPL RADIAT ISOTOPES JI Appl. Radiat. Isot. PD OCT-NOV PY 2000 VL 53 IS 4-5 BP 863 EP 866 DI 10.1016/S0969-8043(00)00229-3 PG 4 WC Chemistry, Inorganic & Nuclear; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Chemistry; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 345TE UT WOS:000088830600051 ER PT J AU Frankle, SC Reedy, RC Young, PG Madigan, WP AF Frankle, SC Reedy, RC Young, PG Madigan, WP TI Improvements to the photon-production data for radiative capture in ENDF SO APPLIED RADIATION AND ISOTOPES LA English DT Article; Proceedings Paper CT 4th Topical Meeting on the Industrial Radiation and Radioisotope Measurement Applications (IRRMA 99) CY OCT 03-07, 1999 CL RALEIGH, NORTH CAROLINA SP Amer Nuclear Soc, Isotopes & Radiat Div, Amer Nuclear Soc, Eastern Carolinas Sect, N Carolina State Univ, Ctr Engn Applicat Radioisotopes, Quantum Res Serv Inc DE ENDF; MCNP; thermal-neutron capture; prompt gamma-ray spectroscopy ID THERMAL-NEUTRON CAPTURE AB High-quality photon-production data from thermal-neutron-capture reactions are important for many applications, including oil-well logging, planetary gamma-ray spectroscopy, and environmental techniques. Radiation transport codes usually access photon-production data from the national U.S. nuclear database, ENDF/B. To improve the photon-production data for thermal-neutron capture, we have compiled and evaluated the energies and yields of gamma rays for most naturally occurring isotopes with Z < 31 and for a few heavier isotopes. The impact of improved photon-production cross sections for thermal-neutron capture in Cl is illustrated by comparing MCNP simulations and experimental measurements for a pulsed neutron oil-well logging instrument. The new compilation of photon-production data is being incorporated into the latest ENDF/B evaluations for each isotope and will be provided for future releases of the ENDF/B database. (C) 2000 Elsevier Science Ltd. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Biomed Res Syst, Houston, TX 77235 USA. RP Frankle, SC (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. OI Reedy, Robert/0000-0002-2189-1303 NR 13 TC 1 Z9 1 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0969-8043 J9 APPL RADIAT ISOTOPES JI Appl. Radiat. Isot. PD OCT-NOV PY 2000 VL 53 IS 4-5 BP 929 EP 935 DI 10.1016/S0969-8043(00)00251-7 PG 7 WC Chemistry, Inorganic & Nuclear; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Chemistry; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 345TE UT WOS:000088830600062 ER PT J AU Liu, HC Borisov, OV Mao, XL Shuttleworth, S Russo, RE AF Liu, HC Borisov, OV Mao, XL Shuttleworth, S Russo, RE TI Pb/U fractionation during Nd : YAG 213 nm and 266 nm laser ablation sampling with inductively coupled plasma mass spectrometry SO APPLIED SPECTROSCOPY LA English DT Article DE laser ablation; fractionation; ICP-MS; Pb/U; crater geometry ID LAM-ICP-MS; ELEMENTAL FRACTIONATION; GLASS SAMPLES; GEOCHRONOLOGY; MICROANALYSIS; VAPORIZATION; DEPOSITION; ZIRCON AB Elemental fractionation during laser ablation sampling was investigated by measuring Pb/U ratios in NIST 610 synthetic glass. Two Nd:YAG lasers with wavelengths of 213 and 266 nm were used to ablate the sample into an inductively coupled plasma mass spectrometer. Pb/U fractionation was observed to be similar for both laser wavelengths, and dependent on the irradiance. For representative Pb/U measurements, the necessary laser irradiance should be >0.6 GW/cm(2). However, if the laser beam is initially focused close to the sample surface, fractionation increases and is influenced by the formation of a crater during repetitive pulsing at a single sample location. As the ratio of crater depth to radius increases, plasma sampling and/or an effective irradiance decrease could cause additional fractionation. A good correlation was found between the fractionation of 14 elements in NIST 610 glass and the logarithms of their oxide melting temperatures. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Chinese Acad Sci, Guangzhou Inst Geochem, Guangzhou 510640, Peoples R China. RP Russo, RE (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. NR 24 TC 39 Z9 40 U1 1 U2 12 PU SOC APPLIED SPECTROSCOPY PI FREDERICK PA 201B BROADWAY ST, FREDERICK, MD 21701 USA SN 0003-7028 J9 APPL SPECTROSC JI Appl. Spectrosc. PD OCT PY 2000 VL 54 IS 10 BP 1435 EP 1442 DI 10.1366/0003702001948565 PG 8 WC Instruments & Instrumentation; Spectroscopy SC Instruments & Instrumentation; Spectroscopy GA 366VL UT WOS:000090026900005 ER PT J AU Han, L Lucas, D Littlejohn, D Kyauk, S AF Han, L Lucas, D Littlejohn, D Kyauk, S TI NIR fiber-optic method with multivariate calibration analysis for determination of inorganic compounds in aqueous solutions SO APPLIED SPECTROSCOPY LA English DT Article DE near-infrared; fiber-optic sensors; evanescent field; aqueous solutions; opaque solutions ID EVANESCENT-WAVE SPECTROSCOPY; NEAR-INFRARED SPECTROSCOPY; IR SPECTROSCOPY; SENSORS; WATER; SPECTRA AB Near-infrared spectra of aqueous solutions were collected by using evanescent-field fiber-optic sensors. The spectra of two- and four-electrolyte solutions were analyzed with a partial least-squares (PLS) algorithm to quantify the measurements. Our results indicate that the electrolytes can be identified and simultaneously determined by using the PLS calibration model. Electrolytes in opaque aqueous mixtures were also studied, and the results are compared with results from clear aqueous solutions. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Environm Energy Technol Div, Berkeley, CA 94720 USA. RP Lucas, D (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Environm Energy Technol Div, Berkeley, CA 94720 USA. NR 20 TC 0 Z9 0 U1 0 U2 2 PU SOC APPLIED SPECTROSCOPY PI FREDERICK PA 201B BROADWAY ST, FREDERICK, MD 21701 USA SN 0003-7028 J9 APPL SPECTROSC JI Appl. Spectrosc. PD OCT PY 2000 VL 54 IS 10 BP 1447 EP 1452 DI 10.1366/0003702001948583 PG 6 WC Instruments & Instrumentation; Spectroscopy SC Instruments & Instrumentation; Spectroscopy GA 366VL UT WOS:000090026900007 ER PT J AU Setterdahl, A Hirasawa, M Bucher, LM Dholakia, CA Jacquot, P Yards, H Miller, F Stevens, FJ Knaff, DB Anderson, LE AF Setterdahl, A Hirasawa, M Bucher, LM Dholakia, CA Jacquot, P Yards, H Miller, F Stevens, FJ Knaff, DB Anderson, LE TI Oxidation-reduction properties of two engineered redox-sensitive mutant Escherichia coli malate dehydrogenases SO ARCHIVES OF BIOCHEMISTRY AND BIOPHYSICS LA English DT Article DE domain-locking disulfides; light activation; redox-sensitive cysteines; reductive activation ID ACTIVATED CHLOROPLAST ENZYMES; DOMAIN-LOCKING DISULFIDE; STRUCTURAL BASIS; THIOREDOXIN-F; SITE; MECHANISM; FERREDOXIN; MODULATION; CYSTEINES; PRINCIPLE AB Redox potentials for two inactivating intrasubunit disulfides that link helix-5 and helix-9 in mutant Escherichia coli malate dehydrogenases have been determined. The E-m is -285 mV when cysteines are at positions 121 and 305 and -295 mV when the cysteines are at positions 122 and 305, Oxidation to the disulfide affects k(cat) but not K-m values. In the single V121C and N122C mutants, the Cys in helix-Ei affects the K-m for oxalacetate, The pH optimum in the direction of malate formation is affected by the redox state of the enzyme. Clearly, a disulfide bond can and does form between Cys residues substituted into positions 121 or 122 in the nucleotide binding domain and 305 in the carbon substrate binding domain of this NAD-dependent malate dehydrogenase, Apparently, crosslinking the domains interferes with catalysis, (C) 2000 Academic Press. C1 Univ Illinois, Dept Biol Sci, Chicago, IL 60607 USA. Texas Tech Univ, Dept Chem & Biochem, Lubbock, TX 79409 USA. Argonne Natl Lab, Biosci Div, Argonne, IL 60439 USA. RP Anderson, LE (reprint author), Univ Illinois, Dept Biol Sci, Chicago, IL 60607 USA. NR 24 TC 3 Z9 3 U1 0 U2 1 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0003-9861 J9 ARCH BIOCHEM BIOPHYS JI Arch. Biochem. Biophys. PD OCT 1 PY 2000 VL 382 IS 1 BP 15 EP 21 DI 10.1006/abbi.2000.1981 PG 7 WC Biochemistry & Molecular Biology; Biophysics SC Biochemistry & Molecular Biology; Biophysics GA 360VE UT WOS:000089687400003 PM 11051092 ER PT J AU Zheng, W Tsvetanov, ZI Schneider, DP Fan, XH Becker, RH Davis, M White, RL Strauss, MA Anderson, JE Annis, J Bahcall, NA Connolly, AJ Csabai, I Davidsen, AF Fukugita, M Gunn, JE Heckman, TM Hennessy, GS Ivezic, Z Knapp, GR Lupton, RH Peng, E Szalay, AS Thakar, AR Yanny, B York, DG AF Zheng, W Tsvetanov, ZI Schneider, DP Fan, XH Becker, RH Davis, M White, RL Strauss, MA Anderson, JE Annis, J Bahcall, NA Connolly, AJ Csabai, I Davidsen, AF Fukugita, M Gunn, JE Heckman, TM Hennessy, GS Ivezic, Z Knapp, GR Lupton, RH Peng, E Szalay, AS Thakar, AR Yanny, B York, DG TI Five high-redshift quasars discovered in commissioning imaging data of the Sloan Digital Sky Survey SO ASTRONOMICAL JOURNAL LA English DT Article DE quasars : general; surveys ID FIELD MULTICOLOR SURVEY; LUMINOSITY FUNCTION; GALAXY; SPECTROPHOTOMETRY; SPECTRUM; EMISSION; SYSTEM AB We report the discovery of five quasars with redshifts of 4.67-5.27 and z'-band magnitudes of 19.5-20.7 (M(B) similar to -27). All were originally selected as distant quasar candidates in optical/near-infrared photometry from the Sloan Digital Sky Survey (SDSS), and most were confirmed as probable high-redshift quasars by supplementing the SDSS data with J and K measurements. The quasars possess strong, broad Ly alpha emission lines, with the characteristic sharp cutoff on the blue side produced by Ly alpha forest absorption. Three quasars contain strong, broad absorption features, and one of them exhibits very strong N v emission. The amount of absorption produced by the Lya forest increases toward higher redshift, and that in the z = 5.27 object (D(A) approximate to 0.7) is consistent with a smooth extrapolation of the absorption seen in lower redshift quasars. The high luminosity of these objects relative to most other known objects at z greater than or similar to 5 makes them potentially valuable as probes of early quasar properties and of the intervening intergalactic medium. C1 Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. Penn State Univ, Dept Astron & Astrophys, University Pk, PA 16802 USA. Princeton Univ Observ, Princeton, NJ 08544 USA. Univ Calif Davis, Dept Phys, Davis, CA 95616 USA. Univ Calif Berkeley, Dept Astron, Berkeley, CA 94720 USA. Space Telescope Sci Inst, Baltimore, MD 21218 USA. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Pittsburgh, Dept Phys & Astron, Pittsburgh, PA 15260 USA. Eotvos Lorand Univ, Dept Phys Complex Syst, H-1117 Budapest, Hungary. Univ Tokyo, Inst Cosm Ray Res, Tanashi, Tokyo 1888502, Japan. Inst Adv Study, Princeton, NJ 08540 USA. USN Observ, Washington, DC 20392 USA. Univ Chicago, Ctr Astron & Astrophys, Chicago, IL 60637 USA. RP Zheng, W (reprint author), Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. RI Csabai, Istvan/F-2455-2012; OI Csabai, Istvan/0000-0001-9232-9898 NR 35 TC 47 Z9 47 U1 0 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0004-6256 J9 ASTRON J JI Astron. J. PD OCT PY 2000 VL 120 IS 4 BP 1607 EP 1611 DI 10.1086/301570 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 364GQ UT WOS:000089884400001 ER PT J AU De Breuck, C Rottgering, H Miley, G van Breugel, W Best, P AF De Breuck, C Rottgering, H Miley, G van Breugel, W Best, P TI A statistical study of emission lines from high redshift radio galaxies SO ASTRONOMY & ASTROPHYSICS LA English DT Review DE radio continuum : galaxies; galaxies : formation; galaxies : evolution ID OPTICAL IDENTIFICATIONS; INFRARED-SPECTROSCOPY; MOLONGLO CATALOG; ACTIVE GALAXIES; COMPLETE SAMPLE; ALPHA EMISSION; SKY SURVEY; 408 MHZ; 151 MHZ; GAS AB We have compiled a sample of 165 radio galaxies from the literature to study the properties of the extended emission line regions and their interaction with the radio source over a large range of redshift 0 < z < 5.2. For each source, we have collected radio (size, lobe distance ratio and power) and spectroscopic parameters (luminosity, line width and equivalent width) for the four brightest UV lines. We also introduce a parameter A(Ly alpha) measuring the asymmetry of the Ly alpha line, assuming the intrinsic redshift of the line is the same as that for the He II lambda 1640 line, and show that this parameter is a good measure of the amount of absorption in the Ly alpha line. Using these 18 parameters, we examine the statistical significance of all 153 mutual correlations, and find the following significant correlations: (i) Ly alpha asymmetry ALy alpha With radio size D and redshift z, (ii) line luminosity with radio power, (iii) line luminosities of Ly alpha, C IV, He II and C III] with each other, and (iv) equivalent widths of Lya, C IV, He II and C III] with each other. We interpret the correlation between redshift and A(Ly alpha) as an increase in the amount of H I around radio galaxies at z > 3. The almost exclusive occurrence of HI absorption in small radio sources could indicate a denser surrounding medium or an un-pressurized, low density region, as suggested by Binette et al. (2000). Correlations (ii) to (iv) provide evidence for a common energy source for the radio power and total emission line luminosity, as found in flux density-limited samples of radio sources. The luminosity of the Ly alpha line relative to the other emission lines and the continuum shows a strong increase at z greater than or similar to 3, coincident with the increase in the amount of associated Hr absorption. This indicates an increased abundance of hydrogen, both ionized and neutral, which may well be the reservoir of primordial hydrogen from which the galaxy is forming. This metallicity evolution is also seen in the nitrogen abundance, which shows a variation of more than an order of magnitude, with the z > 3 radio galaxies occupying only the Z < 2Z. region. To examine the ionization mechanism of the extended emission line regions in HzRGs, we plot the UV emission line data in line-ratio diagnostic diagrams. The diagrams involving the high ionization C IV, He II and C III] lines seem to confirm previous results showing that AGN photo-ionization provides the best fit to the data. However, these models cannot fit the C II]/C III] ratio, which lies closer to the predictions for the highest velocity shock ionization models. We note that the C II] line is five times more sensitive to shock ionization than the high ionization UV lines, and show that a combination of shock and photoionization provides a better overall fit to the integrated spectra of HzRGs. A substantial contribution from shock ionization will show up first in shock sensitive lines like C II] or Mg II. We also confirm the findings of Best et al. (2000b) that shock ionization occurs almost exclusively in small radio sources, and show that the angular size distribution can indeed explain the differences in three HzRG composite spectra. Because most HzRGs have radio sizes 150 kpc, their integrated spectra might well contain a significant contribution from shock ionized emission. C1 Sterrewacht Leiden, NL-2300 RA Leiden, Netherlands. Lawrence Livermore Natl Lab, Inst Geophys & Planetary Phys, Livermore, CA 94550 USA. RP Sterrewacht Leiden, Postbus 9513, NL-2300 RA Leiden, Netherlands. EM debreuck@strw.leidenuniv.nl; rottgeri@strw.leidenuniv.nl; miley@strw.leidenuniv.nl; wil@igpp.ucllnl.org; pbest@strw.leidenuniv.nl NR 106 TC 85 Z9 85 U1 0 U2 0 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 1432-0746 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD OCT PY 2000 VL 362 IS 2 BP 519 EP 543 PG 25 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 376JU UT WOS:000165455100018 ER PT J AU Vasiliev, L Trudolyubov, S Revnivtsev, M AF Vasiliev, L Trudolyubov, S Revnivtsev, M TI RXTE observations of XTE J2012+381 during its 1998 outburst SO ASTRONOMY & ASTROPHYSICS LA English DT Letter DE stars : binaries : general; stars : individual : XTE J2012+381; X-rays : stars ID X-RAY SOURCES; EMISSION; SPECTRA AB We present an analysis of the RXTE observations of X-ray transient source XTE J2012+381 during its 1998 outburst. The spectral and timing properties of the source emission and their evolution during the outburst are very similar to those of the X-ray Novae that have been associated with black hole candidates. C1 Russian Acad Sci, Space Res Inst, Moscow 117810, Russia. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Max Planck Inst Astrophys, D-85740 Garching, Germany. RP Vasiliev, L (reprint author), Russian Acad Sci, Space Res Inst, Profsoyuznaya 84-32, Moscow 117810, Russia. EM leonid@hea.iki.rssi.ru NR 22 TC 6 Z9 6 U1 0 U2 0 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 0004-6361 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD OCT PY 2000 VL 362 IS 3 BP L53 EP L56 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 376JX UT WOS:000165455400005 ER PT J AU Alcock, C Allsman, RA Alves, DR Axelrod, TS Becker, AC Bennett, DP Cook, KH Drake, AJ Freeman, KC Geha, M Griest, K Lehner, MJ Marshall, SL Minniti, D Nelson, CA Peterson, BA Popowski, P Pratt, MR Quinn, PJ Stubbs, CW Sutherland, W Tomaney, AB Vandehei, T Welch, DL AF Alcock, C Allsman, RA Alves, DR Axelrod, TS Becker, AC Bennett, DP Cook, KH Drake, AJ Freeman, KC Geha, M Griest, K Lehner, MJ Marshall, SL Minniti, D Nelson, CA Peterson, BA Popowski, P Pratt, MR Quinn, PJ Stubbs, CW Sutherland, W Tomaney, AB Vandehei, T Welch, DL TI The MACHO project: Microlensing optical depth toward the Galactic bulge from difference image analysis SO ASTROPHYSICAL JOURNAL LA English DT Article DE dark matter; Galaxy : structure; gravitational lensing; stars : low-mass, brown dwarfs ID INNER MILKY-WAY; DARK-MATTER; MAGELLANIC-CLOUD; UNRESOLVED STARS; GALAXY; SEARCH; PHOTOMETRY; EVENTS; MODEL; HALO AB we present the microlensing optical depth toward the Galactic bulge based on the detection of 99 events found in our Difference Image Analysis (DIA) survey. This analysis encompasses 3 yr of data, covering similar to 17 million stars in similar to 4 deg(2), to a source-star baseline magnitude limit of V = 23. The DIA technique improves the quality of photometry in crowded fields, and allows us to detect more microlensing events with faint source stars. We find that this method increases the number of detection events by 85% compared with the standard analysis technique. DIA light curves of the events are presented, and the microlensing lit parameters are given. The total microlensing optical depth is estimated to be tau(total) = 2.43(-0.38)(+0.39) x 10(-6) averaged over eight fields centered at l = 2 degrees.68 and b = -3 degrees.35. For the bulge component, we find tau(bulge) = 3.2(3-0.50)(+0.52) x 10(-6), assuming a 25% stellar contribution from disk sources. These optical depths are in good agreement with the past determinations of the MACHO and OGLE groups, and are higher than predicted by contemporary Galactic models. We show that our observed event timescale distribution is consistent with the distribution expected from normal mass stars, if we adopt the Scalo stellar mass function as our lens mass function. However, we note that since there is still disagreement about the exact form of the stellar mass function, there is uncertainty in this conclusion. Based on our event timescale distribution, we find no evidence for the existence of a large population of brown dwarfs in the direction of the Galactic bulge. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Calif Berkeley, Ctr Particle Astrophys, Berkeley, CA 94720 USA. Australian Natl Univ, Supercomp Facil, Canberra, ACT 0200, Australia. Space Telescope Sci Inst, Baltimore, MD 21218 USA. Res Sch Astron & AStrophys, Canberra, ACT 2611, Australia. Univ Washington, Dept Phys & Astron, Seattle, WA 98195 USA. Univ Notre Dame, Dept Phys, Notre Dame, IN 46556 USA. Univ Calif San Diego, Dept Phys, San Diego, CA 92093 USA. Univ Sheffield, Dept Phys, Sheffield SE 7RH, S Yorkshire, England. Pontificia Univ Catolica Chile, Dept Astron, Santiago 22, Chile. MIT, Space Res Ctr, Cambridge, MA 02139 USA. European So Observ, D-85748 Garching, Germany. Univ Oxford, Dept Phys, Oxford OX1 3RH, England. McMaster Univ, Dept Phys & Astron, Hamilton, ON L8S 4M1, Canada. RP Alcock, C (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RI Stubbs, Christopher/C-2829-2012; Quinn, Peter/B-3638-2013; OI Stubbs, Christopher/0000-0003-0347-1724; Lehner, Matthew/0000-0003-4077-0985 NR 72 TC 146 Z9 149 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD OCT 1 PY 2000 VL 541 IS 2 BP 734 EP 766 DI 10.1086/309484 PN 1 PG 33 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 363FT UT WOS:000089825000022 ER PT J AU Mauche, CW Raymond, JC AF Mauche, CW Raymond, JC TI Extreme Ultraviolet Explorer observations of OY Carinae in superoutburst SO ASTROPHYSICAL JOURNAL LA English DT Article DE binaries : close; binaries : eclipsing; novae, cataclysmic variables; stars : individual (OY Carinae); stars : winds, outflows; ultraviolet : stars ID X-RAY-EMISSION; DISK BOUNDARY-LAYERS; NOVA HT-CASSIOPEIAE; LINE-DRIVEN WINDS; CATACLYSMIC VARIABLES; EUVE OBSERVATIONS; DWARF NOVAE; SS CYGNI; VW HYDRI; ECLIPSE AB The Extreme Ultraviolet Explorer (EUVE) satellite was used for three days beginning on 1997 March 26.96 UT to obtain photometric and spectroscopic observations of the eclipsing SU UMa-type dwarf nova OY Carinae in superoutburst. Because of the longer time on source (143 ks), the larger number of eclipses observed (17), and the higher count rate in the detector (0.5-2.2 counts s(-1)), we are able to significantly strengthen previous reports that there is little or no eclipse by the secondary of the EUV emission region of OY Car in superoutburst. The mean EUVE spectrum extends from 70 to 190 Angstrom and contains broad (FWHM approximate to 1 Angstrom) emission lines of N V, O V-O VI, Ne V-Ne VII, Mg IV-Mg VI, Fe VI-Fe VIII, and possibly Fe XXIII. Good fits of the observed spectrum are obtained with a model (similar to that of Seyfert 2 galaxies) wherein radiation from the boundary layer and accretion disk is scattered into the line of sight by the system's photoionized accretion disk wind. It is possible to trade off continuum luminosity for wind optical depth, but reasonable models have a boundary layer temperature T(bl) approximate to 90-130 kK and a boundary layer and accretion disk luminosity L(bl) = L(disk) less than or similar to 4 x 10(34) ergs s(-1) approximate to 10 L(circle dot) corresponding to a mass accretion rate (M)over dot(a) less than or similar to 10(-8) M(circle dot) yr(-1); an absorbing column density N(H) approximate to 1.6-3.5 x 10(19) cm(-2); and a wind mass-loss rate (M)over dot(w) less than or similar to 10(-10) M(circle dot) yr(-1) approximate to 0.01 M(a). Because radiation pressure alone falls an order of magnitude short of driving such a wind, magnetic forces must also play a role in driving the wind of OY Car in superoutburst. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. RP Mauche, CW (reprint author), Lawrence Livermore Natl Lab, L-43,7000 E Ave, Livermore, CA 94550 USA. EM mauche@cygaus.llnl.gov; jraymond@cfa.harvard.edu NR 59 TC 32 Z9 32 U1 1 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD OCT 1 PY 2000 VL 541 IS 2 BP 924 EP 936 DI 10.1086/309489 PN 1 PG 13 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 363FT UT WOS:000089825000039 ER PT J AU Wojdowski, PS Clark, GW Kallman, TR AF Wojdowski, PS Clark, GW Kallman, TR TI An X-ray spectroscopic study of the SMC X-1/Sk 160 system SO ASTROPHYSICAL JOURNAL LA English DT Article DE pulsars : individual (SMC X-1); stars : winds, outflows; techniques : spectroscopic; X-rays : binaries ID RADIATION-DRIVEN WINDS; VELA X-1; CENTAURUS X-3; STELLAR WIND; HOT STARS; ECLIPSE; DYNAMICS; SPECTRUM; MODELS; BINARY AB We have investigated the composition and distribution of the wind of Sk 160, the supergiant companion of the X-ray star SMC X-l, by comparing an X-ray spectrum of the source, obtained with the ASCA observatory, during an eclipse with the computed spectra of reprocessed radiation from circumstellar matter with various density distributions. We show that the metal abundance in the wind of Sk 160 is no greater than a few tenths of solar, as has been determined for other objects in the Magellanic Clouds. We also show that the observed X-ray spectrum is not consistent with the density distributions of circumstellar matter of the spherically symmetric form derived for line-driven winds, nor with the density distribution derived from a hydrodynamic simulation of the X-ray perturbed and line-driven wind by Blondin & Woo. C1 MIT, Dept Phys, Cambridge, MA 02139 USA. MIT, Space Res Ctr, Cambridge, MA 02139 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. RP Wojdowski, PS (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808, Livermore, CA 94551 USA. NR 35 TC 13 Z9 13 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD OCT 1 PY 2000 VL 541 IS 2 BP 963 EP 976 DI 10.1086/309455 PN 1 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 363FT UT WOS:000089825000042 ER PT J AU Chaput, C Bloom, E Cominsky, L Godfrey, G Hertz, P Scargle, J Shabad, G Wen, H Wood, K Yentis, D AF Chaput, C Bloom, E Cominsky, L Godfrey, G Hertz, P Scargle, J Shabad, G Wen, H Wood, K Yentis, D TI A search for aperiodic millisecond variability in Cygnus X-1 SO ASTROPHYSICAL JOURNAL LA English DT Article DE stars : individual (Cygnus X-1); stars : oscillations; X-rays : stars ID QUASI-PERIODIC OSCILLATIONS; RELATIVISTIC DISKOSEISMOLOGY; DRIPPING HANDRAIL; TRANSIENT CHAOS; POWER SPECTRA; BLACK-HOLES; RAY; MODEL AB We have conducted a search for aperiodic millisecond variability in the integrated 1-25 keV X-ray region of Cyg X-l. We have examined HEAO A-1 archival data and Rossi X-Ray Timing Explorer (RXTE) guest observer data for evidence of excess power above the Poisson noise floor using the relative integral power analysis and the Fourier transform method. Our results are in disagreement with the results of Meekins and coworkers. We attribute the discrepancy to an instrumental effect for which Meekins and coworkers did not apply a correction. With the correction we see no evidence for excess power above 25 Hz in the HEAO A-1 data. Our analysis of RXTE data is in agreement with previously published results of different data sets and shows no indication of excess power above 30 Hz. C1 Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. Sonoma State Univ, Rohnert Park, CA 94928 USA. USN, Res Lab, Washington, DC 20375 USA. NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. RP Chaput, C (reprint author), Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. NR 30 TC 1 Z9 1 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD OCT 1 PY 2000 VL 541 IS 2 BP 1026 EP 1032 DI 10.1086/309444 PN 1 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 363FT UT WOS:000089825000046 ER PT J AU Birn, J Gosling, JT Hesse, M Forbes, TG Priest, ER AF Birn, J Gosling, JT Hesse, M Forbes, TG Priest, ER TI Simulations of three-dimensional reconnection in the solar corona SO ASTROPHYSICAL JOURNAL LA English DT Article DE MHD; Sun : corona; Sun : flares; Sun : magnetic fields ID THIN CURRENT SHEETS; 3-DIMENSIONAL MAGNETIC RECONNECTION; X-RAY TELESCOPE; MASS EJECTIONS; MAGNETOTAIL DYNAMICS; MHD SIMULATIONS; HELMET STREAMER; PLASMA EJECTION; IMPULSIVE FLARE; FIELD AB Using ideal and resistive MHD, we investigate the stability and dynamic evolution of three-dimensional, magnetic field configurations, representing stretched arcade structures above a dipolar "photospheric" magnetic field. Two types of configurations are studied that differ by the amount of divergence ("fanning") of the initial held lines as viewed in the horizontal direction perpendicular to the photospheric magnetic neutral line and, correspondingly, by the radial decrease of magnetic field strength and current density. The two sets of configurations are found to differ in their stability behavior. The strongly fanning fields, associated with a rapid radial decrease of the field strength, current density, and plasma pressure, are more stable. A stability difference is found also when the configurations are first subjected to a converging motion of photospheric footpoints toward the neutral line, which leads to the buildup of thin current sheets in the region above. This current sheet formation is more pronounced for the weakly fanning fields. For similar current density enhancements, the occurrence of anomalous dissipation (resistivity) initiates magnetic reconnection in either configuration. However, the effects are much more drastic in magnitude and spread in the weakly diverging field structure. In the unstable cases, a strongly localized electric field parallel to the magnetic field develops, which results in integrated voltages with maximum values of the order of a few hundred MeV, both on open and closed field lines. For comparison, we studied both low-beta, force-free, and high-beta initial states. The weakly fanning high-beta configurations tend to show more drastic instability effects than the corresponding low-beta fields, but the stabilization of the strongly fanning fields pertains to both low-beta and high-beta fields. The three-dimensional reconnection in the unstable cases generates a region of intertwined magnetic flux tubes with different topologies that lie below a region of closed flux ropes not affected by reconnection. The topological changes could be the source of open flux tubes that are occasionally observed within coronel mass ejections, as recently discussed by Gosling et al. The fast outward flow generated in these simulations affects only the regions of changing topology but does not cause the above-lying closed flux ropes to move (within the times considered). This may be seen as an indication that reconnection may be associated with the onset of a flare, initiated after the eruption of a coronal mass ejection, but is not the driver of the coronal mass ejection itself. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA. Univ New Hampshire, Durham, NH 03824 USA. Univ St Andrews, St Andrews KY16 9SS, Fife, Scotland. RP Los Alamos Natl Lab, MS D466, Los Alamos, NM 87545 USA. EM jbirn@lanl.gov; hesse@gsfc.nasa.gov; terry.forbes@unh.edu; eric@dcs.st-and.ac.uk RI Hesse, Michael/D-2031-2012 NR 67 TC 30 Z9 30 U1 1 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X EI 1538-4357 J9 ASTROPHYS J JI Astrophys. J. PD OCT 1 PY 2000 VL 541 IS 2 BP 1078 EP 1095 DI 10.1086/309452 PN 1 PG 18 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 363FT UT WOS:000089825000050 ER PT J AU Tucker, DL Oemler, A Hashimoto, Y Shectman, SA Kirshner, RP Lin, H Landy, SD Schechter, PL Allam, SS AF Tucker, DL Oemler, A Hashimoto, Y Shectman, SA Kirshner, RP Lin, H Landy, SD Schechter, PL Allam, SS TI Loose groups of galaxies in the Las Campanas Redshift Survey SO ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES LA English DT Article DE catalogs; galaxies : clusters : general; galaxies : distances and redshifts; large-scale structure of universe; surveys ID PISCES-PERSEUS SUPERCLUSTER; LUMINOSITY FUNCTION; DENSITY RELATION; STAR-FORMATION; RICH CLUSTERS; CFA SURVEY; CATALOG; ENVIRONMENT; ZONE AB A "friends-of-friends" percolation algorithm has been used to extract a catalog of deltan/n = 80 density enhancements (groups) from the six slices of the Las Campanas Redshift Survey (LCRS). The full catalog contains 1495 groups and includes 35% of the LCRS galaxy sample. A clean sample of 394 groups has been derived by culling groups from the full sample that either are too close to a slice edge, have a crossing time greater than a Hubble time, have a corrected velocity dispersion of zero, or contain a 55 " "orphan" (a galaxy with a mock redshift that was excluded from the original LCRS redshift catalog due to its proximity to another galaxy-i.e., within 55 "). Median properties derived from the clean sample include a line-of-sight velocity dispersion sigma (los) = 164 km s(-1), crossing time t(cr), = 0.10 H-0(-1), harmonic radius R-h = 0.58 h(-1) Mpc, pairwise separation R-p = 0.64 h(-1) Mpc, virial mass M-vir = 1.90 x 10(13) h(-1) M., total group R-band luminosity L-tot = 1.30 x 10(11) h(-2) L., and R-band mass-to-light ratio M/L = 171 h M./L.; the median number of observed members in a group is three. C1 Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. Carnegie Observ, Pasadena, CA 91101 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. Coll William & Mary, Dept Phys, Williamsburg, VA 23187 USA. MIT, Dept Phys, Cambridge, MA 02139 USA. Helwan Observ, Natl Res Inst Astron & Geophys, Cairo, Egypt. Yale Univ, Dept Astron, New Haven, CT 06520 USA. RP Tucker, DL (reprint author), Fermi Natl Accelerator Lab, MS 127,POB 500, Batavia, IL 60510 USA. NR 54 TC 72 Z9 72 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 SOUTH WOODLAWN AVE, CHICAGO, IL 60637-1603 USA SN 0067-0049 J9 ASTROPHYS J SUPPL S JI Astrophys. J. Suppl. Ser. PD OCT PY 2000 VL 130 IS 2 BP 237 EP 265 DI 10.1086/317348 PG 29 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 378HX UT WOS:000165579900001 ER PT J AU Skowronski, EW Armstrong, N Andersen, G Macht, M McCready, PM AF Skowronski, EW Armstrong, N Andersen, G Macht, M McCready, PM TI Magnetic, microplate-format plasmid isolation protocol for high-yield, sequencing-grade DNA SO BIOTECHNIQUES LA English DT Article ID SOLID-PHASE AB We have developed a rapid, microplate-format plasmid isolation procedure to purify sequencing-grade DNA templates for high-throughput DNA sequencing operations. A modified lysozyme/boiling method is used to produce a plasmid-containing supernatant that is then purified by iron bead capture. After binding, the beads are pelleted in a magnetic field, washed and the DNA eluted in water. The method yields up to 10 mu g plasmid DNA from a I-mt overnight culture in a deep-well microplate. The procedure is suitable for large-scale experiments, amenable to automation and does not require expensive reagents or equipment. The entire protocol can be completed in as little as 2 h, and one technician with a 96-well pipetting station can process rip to 48 plates per day. This protocol is ideal for any high-throughput operation in which template quantity, quality and reproducibility are of primary importance. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA USA. RP Skowronski, EW (reprint author), MJ Bioworks Inc, 384 Oyster Point Blvd,Ste 8, S San Francisco, CA 94080 USA. NR 7 TC 16 Z9 16 U1 0 U2 1 PU EATON PUBLISHING CO PI NATICK PA 154 E. CENTRAL ST, NATICK, MA 01760 USA SN 0736-6205 J9 BIOTECHNIQUES JI Biotechniques PD OCT PY 2000 VL 29 IS 4 BP 786 EP + PG 5 WC Biochemical Research Methods; Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 363XP UT WOS:000089863200019 PM 11056809 ER PT J AU Strizhkov, BN Drobyshev, AL Mikhailovich, VM Mirzabekov, AD AF Strizhkov, BN Drobyshev, AL Mikhailovich, VM Mirzabekov, AD TI PCR amplification on a microarray of gel-immobilized oligonucleotides: Detection of bacterial toxin- and drug-resistant genes and their mutations SO BIOTECHNIQUES LA English DT Article ID POLYMERASE-CHAIN-REACTION; DNA; MICROCHIPS; HYBRIDIZATION AB PCR amplification on a microarray of gel-immobilized primers (microchip) has been developed. One of a pair of PCR primers was immobilized inside a separate microchip polyacrylamide porous gel pad of 0.1 x 0.1 x 0.02 (or 0.04) mu m in size and 0.2 (or 0.4) nL in volume. The amplification was carried out simultaneously both in solution covering the microchip array and inside gel pads. Each gel pad contained the immobilized forward primers, while the fluorescently labeled reverse primers, as well as all components of the amplification reaction, diffused into the gel pads from the solution. To increase the amplification efficiency the forward primers were also added into the solution. The kinetics of amplification was measured in real time in parallel for all gel pads with a fluorescent microscope equipped with a charge-coupled device (CCD) camera. The accuracy of the amplification was assessed by using the melting curves obtained for the duplexes formed by the labeled amplification product and the gel-immobilized primers during the amplification process; alternatively, the duplexes were produced by hybridization of the extended immobilized primers with labeled oligonucleotide probes. The on-chip amplification was applied to detect the anthrax toxin genes and the plasmid-borne beta-lactamase gene responsible for bacterial ampicillin resistance. The allele-specific type of PCR amplification was used to identify the Shiga toxin gene and discriminate it from the Shiga-like one. The genomic mutations responsible for rifampicin resistance of the Mycobacterium tuberculosis strains were detected by the same type of PCR amplification of the rpoB gene fragment isolated from sputum of tuberculosis patients. The on-chip PCR amplification has been shown to be a rapid, inexpensive and powerful tool to test genes responsible for bacterial toxin production and drug resistance, as well as to reveal point nucleotide mutations. C1 Argonne Natl Lab, Biochip Technol Ctr, Argonne, IL 60439 USA. Russian Acad Sci, Engelhardt Inst Mol Biol, Moscow, Russia. RP Mirzabekov, AD (reprint author), Argonne Natl Lab, Biochip Technol Ctr, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 29 TC 52 Z9 59 U1 0 U2 4 PU EATON PUBLISHING CO PI NATICK PA 154 E. CENTRAL ST, NATICK, MA 01760 USA SN 0736-6205 J9 BIOTECHNIQUES JI Biotechniques PD OCT PY 2000 VL 29 IS 4 BP 844 EP + PG 10 WC Biochemical Research Methods; Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 363XP UT WOS:000089863200026 PM 11056816 ER PT J AU Gifford, AN Bruneus, M Gatley, SJ Volkow, ND AF Gifford, AN Bruneus, M Gatley, SJ Volkow, ND TI Cannabinoid receptor-mediated inhibition of acetylcholine release from hippocampal and cortical synaptosomes SO BRITISH JOURNAL OF PHARMACOLOGY LA English DT Article DE cannabinoid receptors; acetylcholine; synaptosomes; hippocampus; cortex ID RAT-BRAIN SLICES; SYNAPTIC TRANSMISSION; CALCIUM CHANNELS; N-TYPE; DOPAMINE RELEASE; CB1 RECEPTOR; NEURONS; AGONIST; DEPOLARIZATION; AUTORECEPTORS AB 1 In previous studies cannabinoid agonists have been found to inhibit and cannabinoid antagonists to enhance electrically-evoked [H-3]-acetycholine (ACh) release in hippocampal slices. The present study was undertaken to determine if similar cannabinoid effects could be observed in synaptosomes. 2 [H-3]-ACh release was evoked by two methods, both sensitive to presynaptic receptor effects. The first involved the addition of 1.3 mM calcium following perfusion with calcium-free I(rebs and the second the addition of 11 mM potassium following perfusion with normal Krebs. 3 In hippocampal synaptosomes the 1.3 mM calcium-evoked release and the high potassium-evoked [H-3]-ACh release were inhibited by the cannabinoid agonist, WIN 55212-2, by 59 and 39%, respectively, and with an EC50 Of approximately 1 nM. WIN 55212-2 produced a similar, although less potent, inhibition of [H-3]-ACh release in cortical synaptosomes. No inhibitory effect of WIN 55212-2 on [H-3]-ACh release in striatal synaptosomes was observed, supporting previous data collected in this area with brain slices. 4 The cannabinoid antagonist, SR 141716A, produced a robust enhancement of 1.3 mM calcium-evoked [H-3]-ACh release in hippocampal synaptosomes (EC50 < 0.3 nM) but had no effect on potassium-evoked release or on [H-3]-ACh release in the cortex or striatum. 5 In conclusion our data demonstrates the inhibitory effects of WIN 55212-2 observed on ACh release in brain slices can be observed in hippocampal and cortex synaptosomes, suggesting a direct action of these compounds on the synaptic terminals. The SR 141716A-induced enhancement of ACh release can similarly be observed in hippocampal synaptosomes and is probably due to an inverse agonist action at constitutively active receptors. C1 Brookhaven Natl Lab, Dept Med, Upton, NY 11973 USA. RP Gifford, AN (reprint author), Brookhaven Natl Lab, Dept Med, Upton, NY 11973 USA. FU NIDA NIH HHS [DA12412, R29 DA012412] NR 26 TC 48 Z9 49 U1 0 U2 0 PU NATURE PUBLISHING GROUP PI BASINGSTOKE PA HOUNDMILLS, BASINGSTOKE RG21 6XS, HAMPSHIRE, ENGLAND SN 0007-1188 J9 BRIT J PHARMACOL JI Br. J. Pharmacol. PD OCT PY 2000 VL 131 IS 3 BP 645 EP 650 DI 10.1038/sj.bjp.0703599 PG 6 WC Pharmacology & Pharmacy SC Pharmacology & Pharmacy GA 361GV UT WOS:000089716100034 PM 11015319 ER PT J AU Augustine, JA DeLuisi, JJ Long, CN AF Augustine, JA DeLuisi, JJ Long, CN TI SURFRAD - A national surface radiation budget network for atmospheric research SO BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY LA English DT Article ID PROGRAM; CLOUD AB A surface radiation budget observing network (SURFRAD) has been established for the United States to support satellite retrieval validation, modeling, and climate, hydrology, and weather research. The primary measurements are the downwelling and upwelling components of broadband solar and thermal infrared irradiance. A hallmark of the network is the measurement and computation of ancillary parameters important to the transmission of radiation. SURFRAD commenced operation in 1995. Presently, it, is made up of six stations in diverse climates, including the moist subtropical environment of the U.S. southeast, the cool and dry northern plains, and the hot and arid desert southwest. Network operation involves a rigorous regimen of frequent calibration, quality assurance, and data quality control. An efficient supporting infrastructure has been created to gather, check, and disseminate the basic data expeditiously. Quality controlled daily processed data files from each station are usually available via the Internet within a day of real time. Data from SURFRAD have been used to validate measurements from NASA's Earth Observing System series of satellites, satellite-bused retrievals of surface erythematogenic radiation, the national ultraviolet index, and real-time National Environmental Satellite, Data, and Information Service (NESDIS) products. It has also been used for carbon sequestration studies, to check radiative transfer codes in various physical models, for basic research and instruction at universities, climate research, and fur many other applications. Two stations now have atmospheric energy flux and soil heat flux instrumentation, making them full surface energy balance sites. It is hoped that eventually all SURFRAD stations will have this capability. C1 NOAA, Air Resources Lab, Surface Radiat Res Branch, Boulder, CO 80303 USA. Pacific NW Natl Lab, Radiat Measurement Program, Richland, WA 99352 USA. RP Augustine, JA (reprint author), NOAA, Air Resources Lab, Surface Radiat Res Branch, 325 Broadway, Boulder, CO 80303 USA. NR 18 TC 162 Z9 162 U1 1 U2 6 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0003-0007 J9 B AM METEOROL SOC JI Bull. Amer. Meteorol. Soc. PD OCT PY 2000 VL 81 IS 10 BP 2341 EP 2357 DI 10.1175/1520-0477(2000)081<2341:SANSRB>2.3.CO;2 PG 17 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 359QR UT WOS:000089624000002 ER PT J AU Cabri, LJ Newville, M Gordon, RA Crozier, ED Sutton, SR McMahon, G Jiang, DT AF Cabri, LJ Newville, M Gordon, RA Crozier, ED Sutton, SR McMahon, G Jiang, DT TI Chemical speciation of gold in arsenopyrite SO CANADIAN MINERALOGIST LA English DT Article DE gold; arsenopyrite; micro-XANES; valence; X-ray microprobe; SIMS; EPMA ID X-RAY-ABSORPTION; BEARING ARSENIAN PYRITE; INVISIBLE GOLD; AU-197 MOSSBAUER; LE-CHATELET; SULFIDES; DEPOSITS; AU; ORES; SPECTROSCOPY AB The speciation of Au in gold-bearing arsenopyrite (FeAsS) from four gold deposits (Olympiada, Sentachan, Sao Bento and Sheba) was determined by micro-X-ray absorption near-edge structure (XANES) on grains well characterized microscopically and by electron-microprobe and secondary-ion mass spectrometry analyses and images. "Invisible" gold in arsenopyrite occurs in two apparently mutually exclusive chemical forms: chemically bound and elemental. Arsenopyrite from the Sentachan, Sao Bento and Sheba deposits contains chemically bound gold. With comparable constituent electronegativities and a white-line feature in the XANES indicating unoccupied An 5d-states, but absorption-edge positions comparable to Au1+ species, the bonding is interpreted as being covalent rather than ionic. The invisible gold in arsenopyrite from the Olympiada deposit, on the other hand, occurs as very small particles of Au-0, probably less than a few nanometers in diameter. Micro-XANES data for the Olympiada and Sentachan arsenopyrite support earlier results obtained by Au-197 Mossbauer spectroscopy on arsenopyrite concentrates. In some arsenopyrite crystals, the gold concentration is closely related to growth zoning. This feature represents conditions during crystallization and does not correlate with the chemical form of the gold. Similarly, selenium, where present, correlates with gold in some deposits and not in others, irrespective of the gold speciation. The finding of two types of invisible gold in arsenopyrite from different deposits has beneficial implications for extractive metallurgy. C1 Canada Ctr Mineral & Energy Technol, Ottawa, ON K1A 0G1, Canada. Univ Chicago, Consortium Adv Radiat Sources, Chicago, IL 60637 USA. Simon Fraser Univ, Dept Phys, Burnaby, BC V5A 1S6, Canada. Argonne Natl Lab, PNC CAT, Adv Photon Source, Argonne, IL 60439 USA. Univ Chicago, Dept Geophys Sci, Chicago, IL 60637 USA. RP Cabri, LJ (reprint author), Canada Ctr Mineral & Energy Technol, 555 Booth St, Ottawa, ON K1A 0G1, Canada. RI McMahon, Greg/C-3991-2013 NR 51 TC 64 Z9 76 U1 1 U2 12 PU MINERALOGICAL ASSOC CANADA PI NEPEAN PA CITYVIEW 78087, NEPEAN, ONTARIO K2G 5W2, CANADA SN 0008-4476 J9 CAN MINERAL JI Can. Mineral. PD OCT PY 2000 VL 38 BP 1265 EP 1281 DI 10.2113/gscanmin.38.5.1265 PN 5 PG 17 WC Mineralogy SC Mineralogy GA 385QY UT WOS:000166016200014 ER PT J AU Hillhouse, HW van Egmond, JW Tsapatsis, M Hanson, JC Larese, JZ AF Hillhouse, HW van Egmond, JW Tsapatsis, M Hanson, JC Larese, JZ TI Synthesis and characterization of ordered arrays of topological defects in mesoporous silica films SO CHEMISTRY OF MATERIALS LA English DT Article ID SURFACE PATTERNS; MORPHOGENESIS AB Defects are commonly found throughout crystalline solids and often have a pronounced effect on mechanical, optical, chemical, and transport properties.(1) Liquid-crystalline materials also contain defects resulting in topologies where the director field is undefined at a point or on a curve at the defect core.(2) In both the crystalline and liquid-crystalline state, defects typically disrupt long-range order, rendering the material isotropic at large length scales. Acid synthesis of mesoporous silica proceeds through a liquid-crystalline stage(3) in which defects determine the channel orientation of the resulting porous material. Previously, hexagonal phase mesoporous silica films have been grown with channels dominantly oriented parallel to the substrate.(4-6) Here, we report that ordered arrays of topological defects can be generated leading to mesoporous silica films with long-range orientation and rotational order with approximately half of the channels oriented perpendicular to the substrate by growing the films epitaxially on a crystalline substrate in a shear flow field. Two-dimensional X-ray diffraction patterns recorded from films grown on mica are "single-crystal-like," exhibiting B-fold symmetry that is rotationally invariant over the entire film. C1 Univ Massachusetts, Dept Chem Engn, Amherst, MA 01003 USA. Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. RP Tsapatsis, M (reprint author), Univ Massachusetts, Dept Chem Engn, Amherst, MA 01003 USA. RI Hanson, jonathan/E-3517-2010 NR 20 TC 24 Z9 25 U1 2 U2 8 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0897-4756 J9 CHEM MATER JI Chem. Mat. PD OCT PY 2000 VL 12 IS 10 BP 2888 EP 2893 DI 10.1021/cm000425k PG 6 WC Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 366YT UT WOS:000090034400014 ER PT J AU Carrado, KA Xu, L Gregory, DM Song, K Seifert, S Botto, RE AF Carrado, KA Xu, L Gregory, DM Song, K Seifert, S Botto, RE TI Crystallization of a layered silicate clay as monitored by small-angle X-ray scattering and NMR SO CHEMISTRY OF MATERIALS LA English DT Article ID SOLID-STATE NMR; CHEMICAL-SHIFT; SI-29; SPECTROSCOPY; AL-27; MINERALS; ZEOLITE; MONTMORILLONITE; SUSPENSIONS; KAOLINITE AB The 48-h hydrothermal crystallization of a magnesium silicate clay called hectorite has been investigated in detail. Tetraethylammonium (TEA) ions are used to aid crystallization and become incorporated as the exchange cat;ions within the interlayers. Data from small-angle X-ray scattering (SAXS) using aliquots ex situ are consistent with results obtained previously by X-ray powder diffraction (XRD), thermal gravimetric analysis (TGA), atomic force microscopy (AFM), and IR. All these techniques see clay crystallites beginning to form within the first few hours of reaction. Si-29 NMR displays a visible clay silicate peak after just 1 h. Solid-state C-13 NMR shows evidence of TEA-clay formation in as little as 30 min and also that 80% of the final TEA loading is accomplished in the first 10-12 h. Up to 36 h more is needed to incorporate the remaining 20% of TEA, indicating that a slower event is dominating at the later stages of crystallization. Data from 13C NMR and SAXS are compared to and are consistent with data from earlier AFM experiments. All present a scenario where initial nucleation and crystallization end after about 14 h, after which this occurs to a lesser extent and primarily agglomeration of particles is taking place. The SAXS data show this in progressively increasing power law values, indicating more "open" structures that condense into more dense structures with time. In addition, the first in situ study of clay crystallization of any kind was performed by in situ SAXS. A possible clay crystallization mechanism is proposed. C1 Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. RP Carrado, KA (reprint author), Argonne Natl Lab, Div Chem, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 50 TC 34 Z9 38 U1 3 U2 16 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0897-4756 J9 CHEM MATER JI Chem. Mat. PD OCT PY 2000 VL 12 IS 10 BP 3052 EP 3059 DI 10.1021/cm000366a PG 8 WC Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 366YT UT WOS:000090034400036 ER PT J AU Southworth, GR Peterson, MJ Ryon, MG AF Southworth, GR Peterson, MJ Ryon, MG TI Long-term increased bioaccumulation of mercury in largemouth bass follows reduction of waterborne selenium SO CHEMOSPHERE LA English DT Article DE mercury; bioaccumulation; selenium; deformities ID WABIGOON RIVER SYSTEM; FISH; CONTAMINATION; ECOSYSTEMS AB Average mercury concentrations in largemouth bass from Rogers Quarry in east Tennessee were found to increase steadily following the elimination of selenium-rich discharges of fly ash to the quarry in 1989. From 1990 to 1998, mean mercury concentrations (adjusted to compensate for the covariance between individual fish weight and mercury concentration) in bass rose from 0.02 to 0.61 mg/kg. There was no indication that the rate increase was slowing or that mercury concentrations in fish were approaching a plateau or steady state. Mean selenium concentrations in bass declined from 3 to 1 mg/kg over the first five years of the study, but remained at 1-1.5 mg/kg (about twice typical concentrations in bass from local reference sites) for the last three years of the study. Gross physical abnormalities were common in fish from the site in the first three years after elimination of fly ash discharges but disappeared after two more years. Although it remains possible that other chemical or physical changes related to fly ash disposal in the system were associated with increased mercury bioaccumulation, the most likely explanation is that selenium played a critical role. It appears as though aqueous selenium enrichment was capable of having a profound effect on mercury bioaccumulation in this system but at the cost of causing a high incidence of gross abnormalities in fish. However, it is possible that selenium concentrations between the national ambient water quality criterion for the protection of aquatic life, 5 mu g/l, and that now found in Rogers Quarry (<2 mu g/l) could reduce mercury bioaccumulation without causing adverse effects on aquatic biota and fish-eating wildlife. (C) 2000 Elsevier Science Ltd. All rights reserved. C1 Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. RP Southworth, GR (reprint author), Oak Ridge Natl Lab, Div Environm Sci, POB 2008,Bldg 1505,MS 6036, Oak Ridge, TN 37831 USA. NR 25 TC 31 Z9 35 U1 2 U2 10 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0045-6535 J9 CHEMOSPHERE JI Chemosphere PD OCT PY 2000 VL 41 IS 7 BP 1101 EP 1105 DI 10.1016/S0045-6535(99)00562-7 PG 5 WC Environmental Sciences SC Environmental Sciences & Ecology GA 322RD UT WOS:000087521800018 PM 10879829 ER PT J AU Covey, C Abe-Ouchi, A Boer, GJ Boville, BA Cubasch, U Fairhead, L Flato, GM Gordon, H Guilyardi, E Jiang, X Johns, TC Le Treut, H Madec, G Meehl, GA Miller, R Noda, A Power, SB Roeckner, E Russell, G Schneider, EK Stouffer, RJ Terray, L von Storch, JS AF Covey, C Abe-Ouchi, A Boer, GJ Boville, BA Cubasch, U Fairhead, L Flato, GM Gordon, H Guilyardi, E Jiang, X Johns, TC Le Treut, H Madec, G Meehl, GA Miller, R Noda, A Power, SB Roeckner, E Russell, G Schneider, EK Stouffer, RJ Terray, L von Storch, JS TI The seasonal cycle in coupled ocean-atmosphere general circulation models SO CLIMATE DYNAMICS LA English DT Article ID SURFACE AIR-TEMPERATURE; SPATIAL VARIABILITY; CLIMATE SENSITIVITY; CO2; INCREASE; PROJECT; LAYER AB We examine the seasonal cycle of near-surface air temperature simulated by 17 coupled ocean-atmosphere general circulation models participating in the Coupled Model Intercomparison Project (CMIP). Nine of the models use ad hoc "flux adjustment" at the ocean surface to bring model simulations close to observations of the present-day climate. We group flux-adjusted and non-flux-adjusted models separately and examine the behaviol- of each class. When averaged over all of the flux-adjusted model simulations, near-surface air temperature falls within 2 K of observed values over the oceans. The corresponding average over non-flux-adjusted models shows errors up to similar to6 K in extensive ocean areas. Flux adjustments are not directly applied over land, and near-surface land temperature errors are substantial in the average over flux-adjusted models, which systematically underestimates (by similar to5 K) temperature in areas of elevated terrain. The corresponding average over non-flux-adjusted models forms a similar error pattern (with somewhat increased amplitude) over land. We use the temperature difference between July and January to measure seasonal cycle amplitude. Zonal means of this quantity from the individual flux-adjusted models form a fairly tight cluster (all within similar to 30% of the mean) centered on the observed values. The nonflux-adjusted models perform nearly as well at most latitudes. In Southern Ocean mid-latitudes, however, the non-flux-adjusted models overestimate the magnitude of January-minus-July temperature differences by similar to5 K due to an overestimate of summer (January) near-surface temperature. This error is common to five of the eight non-flux-adjusted models. Also, over Northern Hemisphere mid-latitude land areas, zonal mean differences between July and January temperatures simulated by the non-flux-adjusted models show a greater spread (positive and negative) about observed values than results from the flux-adjusted models. Elsewhere, differences between the two classes of models are less obvious. At no latitude is the zonal mean difference between averages over the two classes of models greater than the standard deviation over models. The ability of coupled GCMs to simulate a reasonable seasonal cycle is a necessary condition for confidence in their prediction of long-term climatic changes (such as global warming), but it is not a sufficient condition unless the seasonal cycle and long-term changes involve similar climatic processes. To test this possible connection, we compare seasonal cycle amplitude with equilibrium warming under doubled atmospheric carbon dioxide for the models in our data base. A small but positive correlation exists between these two quantities. This result is predicted by a simple conceptual model of the climate system, and it is consistent with other modeling experience, which indicates that the seasonal cycle depends only weakly on climate sensitivity. C1 Univ Calif Lawrence Livermore Natl Lab, Program Climate Model Diag & Intercomparison, Livermore, CA 94550 USA. Ctr Climate Syst Res, Tokyo 153, Japan. Canadian Ctr Climate Modeling & Anal, Victoria, BC V8W 2Y2, Canada. Natl Ctr Atmospher Res, Boulder, CO 80307 USA. German Climate Comp Ctr, D-20146 Hamburg, Germany. Max Planck Inst Meteorol, D-20146 Hamburg, Germany. CNRS, Meteorol Dynam Lab, F-75252 Paris 05, France. CSIRO, Div Atmospher Res, Mordialloc, Vic 3195, Australia. CERFACS, Climate Modeling & Global Change Team, F-31057 Toulouse, France. Goddard Inst Space Studies, New York, NY 10025 USA. UK Meteorol Off, Hadley Ctr, Bracknell RG12 2SY, Berks, England. Lab Dynam Oceanog & Climatol, F-75252 Paris 05, France. Meteorol Res Inst, Tsukuba, Ibaraki 305, Japan. Bur Meteorol Res Ctr, Melbourne, Vic 3001, Australia. Ctr Ocean Land Atmosphere Studies, Calverton, MD 20705 USA. Geophys Fluid Dynam Lab, Princeton, NJ 08542 USA. Univ Hamburg, Inst Meteorol, D-20146 Hamburg, Germany. RP Covey, C (reprint author), Univ Calif Lawrence Livermore Natl Lab, Program Climate Model Diag & Intercomparison, Mail Code L-264, Livermore, CA 94550 USA. RI madec, gurvan/E-7825-2010; Guilyardi, Eric/D-4868-2011; Abe-Ouchi, Ayako/M-6359-2013; Flato, Gregory/K-6711-2015; Terray, Laurent/B-8056-2008 OI madec, gurvan/0000-0002-6447-4198; Guilyardi, Eric/0000-0002-2255-8625; Abe-Ouchi, Ayako/0000-0003-1745-5952; Terray, Laurent/0000-0001-5512-7074 NR 33 TC 32 Z9 35 U1 1 U2 8 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0930-7575 J9 CLIM DYNAM JI Clim. Dyn. PD OCT PY 2000 VL 16 IS 10-11 BP 775 EP 787 DI 10.1007/s003820000081 PG 13 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 368LD UT WOS:000090117700004 ER PT J AU Pfahl, UJ Ross, MC Shepherd, JE Pasamehmetoglu, KO Unal, C AF Pfahl, UJ Ross, MC Shepherd, JE Pasamehmetoglu, KO Unal, C TI Flammability limits, ignition energy, and flame speeds in H-2-CH4-NH3-N2O-O-2-N-2 mixtures SO COMBUSTION AND FLAME LA English DT Article ID BURNING VELOCITIES AB Experiments on flammability limits, ignition energies, and flame speeds were carried out in a 11.25- and a 400-liter combustion vessel at initial pressures and temperatures of 100 kPa and 295 K, respectively. Flammability maps of hydrogen-nitrous oxide-nitrogen, methane-nitrous oxide-nitrogen, ammonia-nitrous oxide-nitrogen, and ammonia-nitrous oxide-air, as well as lean flammability limits of various hydrogen-methane-ammonia-nitrous oxide-oxygen-nitrogen mixtures were determined. ignition energy bounds of methane-nitrous oxide, ammonia-nitrous oxide, and ammonia-nitrous oxide-nitrogen mixtures have been determined and the influence of small amounts of oxygen on the flammability of methane-nitrous oxide-nitrogen mixtures has been investigated. Flame speeds have been measured and laminar burning velocities have been determined for ammonia-air-nitrous oxide and various hydrogen-methane-ammonia-nitrous oxide-oxygen-nitrogen mixtures. Lower and upper flammability limits (mixing fan on, turbulent conditions) for ignition energies of 8 J are: H-2-N2O: 4.5 similar to 5.0% H-2(LFL), 76 similar to 80% H-2(UFL); CH4-N2O: 2.5 similar to 3.0% CH4(LFL), 43 similar to 50% CH4(UFL); NH3-N2O: 5.0 similar to 5.2% NH3(LFL), 67.5 similar to 68% NH3(UFL). Inerting concentrations are: H-2-N2O-N-2: 76% N-2; CH4-N2O-N-2: 70.5% N-2; NH3-N2O-N-2: 61% N-2; NH3-N2O-air: 85% air. Flammability limits of methane-nitrous oxide-nitrogen mixtures show no pronounced dependence on small amounts of oxygen (<5%). Generally speaking, flammable gases with large initial amounts of nitrous oxide or ammonia show a strong dependence of flammability limits on ignition energy. (C) 2000 by The Combustion Institute. C1 CALTECH, Grad Aeronaut Labs, Pasadena, CA 91125 USA. Univ Calif Los Alamos Natl Lab, Technol & Safety Assessment Div, Los Alamos, NM 87545 USA. RP Pfahl, UJ (reprint author), CALTECH, Grad Aeronaut Labs, Pasadena, CA 91125 USA. RI Shepherd, Joseph/B-5997-2014 OI Shepherd, Joseph/0000-0003-3181-9310 NR 45 TC 44 Z9 46 U1 2 U2 11 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0010-2180 J9 COMBUST FLAME JI Combust. Flame PD OCT PY 2000 VL 123 IS 1-2 BP 140 EP 158 DI 10.1016/S0010-2180(00)00152-8 PG 19 WC Thermodynamics; Energy & Fuels; Engineering, Multidisciplinary; Engineering, Chemical; Engineering, Mechanical SC Thermodynamics; Energy & Fuels; Engineering GA 357AJ UT WOS:000089476100009 ER PT J AU Nilsen, J Dunn, J Li, YL Osterheld, AL Shlyaptsev, VN Barbee, TW Hunter, JR AF Nilsen, J Dunn, J Li, YL Osterheld, AL Shlyaptsev, VN Barbee, TW Hunter, JR TI Review of Ni-like ion X-ray laser research at Lawrence Livermore National Laboratory SO COMPTES RENDUS DE L ACADEMIE DES SCIENCES SERIE IV PHYSIQUE ASTROPHYSIQUE LA English DT Article DE X-ray laser ID TRANSIENT GAIN; NICKEL-LIKE; NM; SATURATION; TITANIUM; TABLETOP AB We have demonstrated saturated output on several nickel-like ion X-ray lasers ranging from niobium to silver by using a psec, high-power, chirped-pulse-amplification, tabletop laser. These results have been achieved at wavelengths from 20.3 to 13.9 nm on the Ni-like 3d(9)4d(1)S(o) --> 3d(9)4p(1)P(1) laser line using a total of 5 to 7 J of energy in a traveling wave excitation scheme. Strong amplification is also observed for Ni-like Sn at 11.9 nm. Gain of 41 cm(-1), gain-length product of 18, and output energy of 12 muJ are measured for the Ni-like Pd line at 14.7 nm. For Ni-Iike Mo, 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. For Mo we measure an output energy of 2 muJ and a gain-length product of 16.6. To model the Mo 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 and observed for both the 3d(9)4d(1)S(o) --> 3d(9)4p(1)P(1) laser line at 18.9 nm and the 3d(9)4f(1)P(1) --> 3d(9)4d(1)P(1) photopumped line at 22.6 nm. (C) 2000 Academie des sciences/Editions scientifiques et medicales Elsevier SAS. C1 Lawrence Livermore Natl Lab, Inst Laser Sci & Applicat, Livermore, CA 94550 USA. Lawrence Livermore Natl Lab, Dept Appl Sci, Livermore, CA 94550 USA. Argonne Natl Lab, Argonne, IL 60439 USA. RP Nilsen, J (reprint author), Lawrence Livermore Natl Lab, Inst Laser Sci & Applicat, Livermore, CA 94550 USA. NR 18 TC 0 Z9 0 U1 0 U2 1 PU ELSEVIER FRANCE-EDITIONS SCIENTIFIQUES MEDICALES ELSEVIER PI PARIS PA 23 RUE LINOIS, 75724 PARIS, FRANCE SN 1296-2147 J9 CR ACAD SCI IV-PHYS JI C. R. Acad. Sci. Ser. IV-Phys. Astrophys. PD OCT PY 2000 VL 1 IS 8 BP 1035 EP 1044 DI 10.1016/S1296-2147(00)01111-2 PG 10 WC Astronomy & Astrophysics; Physics, Multidisciplinary SC Astronomy & Astrophysics; Physics GA 391BM UT WOS:000166334300005 ER PT J AU Aminzadeh, F Barhen, J Glover, CW Toomarian, NB AF Aminzadeh, F Barhen, J Glover, CW Toomarian, NB TI Reservoir parameter estimation using a hybrid neural network SO COMPUTERS & GEOSCIENCES LA English DT Article DE neural networks; oil exploration; reservoir characterization; seismic attributes AB The accuracy of an artificial neural network (ANN) algorithm is a crucial issue in the estimation of an oil field's reservoir properties from the log and seismic data. This paper demonstrates the use of the k-fold cross validation technique to obtain confidence bounds on an ANN's accuracy statistic from a finite sample set. In addition, we also show that an ANN's classification accuracy is dramatically improved by transforming the ANN's input feature space to a dimensionally smaller, new input space. The new input space represents a feature space that maximizes the linear separation between classes. Thus, the ANN's convergence time and accuracy are improved because the ANN must merely find nonlinear perturbations to the starting linear decision boundaries. These techniques for estimating ANN accuracy bounds and feature space transformations are demonstrated on the problem of estimating the sand thickness in an oil field reservoir based only on remotely sensed seismic data. (C) 2000 Elsevier Science Ltd. All rights reserved. C1 dGB USA & FACT Inc, Sugarland, TX 77478 USA. Oak Ridge Natl Lab, Ctr Engn Syst Adv Res, Oak Ridge, TN USA. CALTECH, Jet Prop Lab, Pasadena, CA 91125 USA. RP Aminzadeh, F (reprint author), dGB USA & FACT Inc, 14019 SW Freeway,Suite 301-230, Sugarland, TX 77478 USA. NR 10 TC 17 Z9 19 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0098-3004 J9 COMPUT GEOSCI-UK JI Comput. Geosci. PD OCT PY 2000 VL 26 IS 8 BP 869 EP 875 DI 10.1016/S0098-3004(00)00027-3 PG 7 WC Computer Science, Interdisciplinary Applications; Geosciences, Multidisciplinary SC Computer Science; Geology GA 346HM UT WOS:000088865000002 ER PT J AU Singhose, W Porter, L Kenison, M Kriikku, E AF Singhose, W Porter, L Kenison, M Kriikku, E TI Effects of hoisting on the input shaping control of gantry cranes SO CONTROL ENGINEERING PRACTICE LA English DT Article DE vibration; input shaping; command generation; crane dynamics ID OVERHEAD CRANES; VIBRATION AB The dynamic behavior of a planar gantry crane with hoisting of the load is investigated. The command generation method of input shaping is proposed for reduction of the residual vibration. Several versions of input shaping are evaluated and compared with time-optimal rigid-body commands over a wide range of parameters. Input shaping provides significant reduction in both the residual and transient oscillations, even when the hoisting distance is a large percentage of the cable length. Experimental results from a 15-ton gantry crane at the Savannah River Technology Center are used to support the numerical results. (C) 2000 Elsevier Science Ltd. AII rights reserved. C1 Georgia Inst Technol, Dept Mech Engn, Atlanta, GA 30332 USA. ATO, DARPA, Arlington, VA 22203 USA. Schlumberger, Rosharon, TX 77583 USA. Westinghouse Savannah River Co, Savannah River Technol Ctr, Aiken, SC USA. RP Georgia Inst Technol, Dept Mech Engn, 813 Ferst Dr, Atlanta, GA 30332 USA. EM bill.singhose@me.gatech.edu; lporter@snap.org; kenison@mars.rosharon.wireline.slb.com; eric.kriikku@srs.gov NR 21 TC 146 Z9 162 U1 7 U2 32 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0967-0661 EI 1873-6939 J9 CONTROL ENG PRACT JI Control Eng. Practice PD OCT PY 2000 VL 8 IS 10 BP 1159 EP 1165 DI 10.1016/S0967-0661(00)00054-X PG 7 WC Automation & Control Systems; Engineering, Electrical & Electronic SC Automation & Control Systems; Engineering GA 353ZL UT WOS:000089305300006 ER PT J AU Isaacs, HS Adzic, G Jeffcoate, CS AF Isaacs, HS Adzic, G Jeffcoate, CS TI 2000 W. R. Whitney Award Lecture: Visualizing corrosion SO CORROSION LA English DT Article; Proceedings Paper CT Corrosion 2000 Meeting CY MAR, 2000 CL ORLANDO, FLORIDA DE AA100; AA2024; AA5052; AA7075; aluminum; chloride; localized corrosion; pH ID IONS AB Using a broad-range pH indicator, the corrosion of At and At alloys in chloride-containing agar gels was studied. Distinct changes in pH were observed at low-PH anodic sites and at high-pH cathodes. There was a definite edge effect that occurred when gels were placed directly on the metal, which dominated the pattern of corrosion. Wet-abraded surfaces initially showed a general type of corrosion, whereas dry-abraded surfaces showed localized corrosion under the get. Pure At, AA1100 (UNS A91110), AA2024 (UNS A92024), and AA5052 (UNS A95052) all showed pitting in contact with agar gels when the edge effect was prevented. Abraded AA7075 (UNS A97075) exhibited a filiform type of corrosion caused by high concentrations of corrosion product initiating corrosion ahead of the growing site. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. Ohio State Univ, Dept Mat Sci & Engn, Columbus, OH 43210 USA. RP Isaacs, HS (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. NR 17 TC 26 Z9 26 U1 3 U2 11 PU NATL ASSN CORROSION ENG PI HOUSTON PA 1440 SOUTH CREEK DRIVE, HOUSTON, TX 77084-4906 USA SN 0010-9312 J9 CORROSION JI Corrosion PD OCT PY 2000 VL 56 IS 10 BP 971 EP 978 PG 8 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 565DX UT WOS:000176354600001 ER PT J AU Khaselev, O Turner, JA AF Khaselev, O Turner, JA TI Anodic oxidation of GaInP2 SO CORROSION SCIENCE LA English DT Article DE oxidation; GaInP2; anodic films ID GAP; DIODES; OXIDES; FILMS; INP AB Anodic films have been grown on GaInP2 at a constant applied current density in phosphate solutions with pH 4, 7 and 10. XPS analysis revealed that the chemical composition of the anodic films formed in the solutions with pH 7 and 10 is non-uniform with In excess and corresponding Ga and P deficiency in outer layer. The anodic films formed in the solution with pH 4 had uniform composition, apparently due to preferential dissolution of In in this solution. The anodic films were stable when exposed to air for several weeks. (C) 2000 Elsevier Science Ltd. All rights reserved. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Khaselev, O (reprint author), Lucent Technol, 236 Richmond Valley Rd, Staten Isl, NY 10309 USA. NR 20 TC 3 Z9 3 U1 0 U2 4 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0010-938X J9 CORROS SCI JI Corrosion Sci. PD OCT PY 2000 VL 42 IS 10 BP 1831 EP 1838 DI 10.1016/S0010-938X(00)00016-0 PG 8 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 346WE UT WOS:000088893400010 ER PT J AU Brunger, AT Laue, ED AF Brunger, AT Laue, ED TI Biophysical methods - New approaches to study macromolecular structure and function - Editorial overview SO CURRENT OPINION IN STRUCTURAL BIOLOGY LA English DT Editorial Material C1 Stanford Univ, Howard Hughes Med Inst, Stanford, CA 94305 USA. Stanford Univ, Dept Mol & Cellular Physiol, Stanford, CA 94305 USA. Stanford Univ, Dept Neurol & Neurol Sci, Stanford, CA 94305 USA. Stanford Univ, Stanford Synchrotron Radiat Lab, Stanford, CA 94305 USA. Univ Cambridge, Dept Biochem, Cambridge CB2 1GA, England. RP Brunger, AT (reprint author), Stanford Univ, Howard Hughes Med Inst, Stanford, CA 94305 USA. NR 0 TC 4 Z9 4 U1 0 U2 0 PU CURRENT BIOLOGY LTD PI LONDON PA 84 THEOBALDS RD, LONDON WC1X 8RR, ENGLAND SN 0959-440X J9 CURR OPIN STRUC BIOL JI Curr. Opin. Struct. Biol. PD OCT PY 2000 VL 10 IS 5 BP 557 EP 557 DI 10.1016/S0959-440X(00)00130-5 PG 1 WC Biochemistry & Molecular Biology; Cell Biology SC Biochemistry & Molecular Biology; Cell Biology GA 366AR UT WOS:000089983100008 ER PT J AU Adams, PD Grosse-Kunstleve, RW AF Adams, PD Grosse-Kunstleve, RW TI Recent developments in software for the automation of crystallographic macromolecular structure determination SO CURRENT OPINION IN STRUCTURAL BIOLOGY LA English DT Article ID ELECTRON-DENSITY MAPS; STRUCTURE REFINEMENT; HEAVY-ATOM; MOLECULAR-REPLACEMENT; ANOMALOUS SIGNAL; MAD; QUALITY; SEARCH; SOLVENT; IMPROVEMENT AB The automation of macromolecular structure determination by X-ray crystallography has long been a goal for many researchers. Recently, there have been improvements in the underlying algorithms, some of which have been implemented in software packages that deal with multiple stages of the structure determination process. These first steps towards complete automation have made X-ray crystallography more efficient. C1 Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Adams, PD (reprint author), Lawrence Berkeley Natl Lab, Mailstop 4-230,1 Cyclotron Rd, Berkeley, CA 94720 USA. RI Adams, Paul/A-1977-2013 OI Adams, Paul/0000-0001-9333-8219 NR 49 TC 10 Z9 11 U1 1 U2 1 PU CURRENT BIOLOGY LTD PI LONDON PA 84 THEOBALDS RD, LONDON WC1X 8RR, ENGLAND SN 0959-440X J9 CURR OPIN STRUC BIOL JI Curr. Opin. Struct. Biol. PD OCT PY 2000 VL 10 IS 5 BP 564 EP 568 DI 10.1016/S0959-440X(00)00132-9 PG 5 WC Biochemistry & Molecular Biology; Cell Biology SC Biochemistry & Molecular Biology; Cell Biology GA 366AR UT WOS:000089983100010 PM 11042455 ER PT J AU Butterworth, R Wilson, CJ Herron, NF Greene, RSB Cunningham, RB AF Butterworth, R Wilson, CJ Herron, NF Greene, RSB Cunningham, RB TI Geomorphic controls on the physical and hydrologic properties of soils in a valley floor SO EARTH SURFACE PROCESSES AND LANDFORMS LA English DT Article DE soil hydraulic properties; catchment hydrology; valley floor; floodplain; fan; toeslope ID HYDRAULIC CONDUCTIVITY; PREDICTION; CATCHMENTS; ZONES AB The distribution of soil hydraulic and physical properties strongly influences runoff processes in landscapes. Although much work has been done to quantify and predict the properties of hillslope soils, far less is known about the distribution of soil properties in valley floors. A technique that links the estimation and distribution of soil hydraulic properties in valleys, with easily identified geomorphic features, was developed along a 2 km length of a valley at Brooks Creek in New South Wales, Australia. Soil physical and hydraulic property data were collected across a set of floodplain and fan features within the valley and analysed statistically to determine if soil properties varied significantly between geomorphic features and stratigraphic layers. The results show that the depth-averaged saturated hydraulic conductivity, K-s, of the soil varies significantly with landform: fan units have K-g values that are twice that of floodplains and colluvial toeslope deposits have K-s values four times higher than floodplains. Given the notorious variability of K-s values in space, the strong statistical separation of soil properties by landform, backed up by strong separation of soil particle size by landform, suggests a way forward in understanding the distribution of soil properties in valleys and their influence on catchment hydrology. Copyright (C) 2000 John Wiley & Sons, Ltd. C1 Australian Natl Univ, Dept Geog, Canberra, ACT 0200, Australia. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. CRCCH, Canberra, ACT 2601, Australia. Univ Melbourne, Dept Geog, Parkville, Vic 3052, Australia. Australian Natl Univ, Stat Consulting Unit, Canberra, ACT 0200, Australia. CSIRO Land & Water, Canberra, ACT, Australia. RP Butterworth, R (reprint author), 3-77 Page Ave, N Nowra, NSW 2541, Australia. NR 42 TC 4 Z9 4 U1 1 U2 7 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 0197-9337 J9 EARTH SURF PROC LAND JI Earth Surf. Process. Landf. PD OCT PY 2000 VL 25 IS 11 BP 1161 EP 1179 DI 10.1002/1096-9837(200010)25:11<1161::AID-ESP119>3.3.CO;2-O PG 19 WC Geography, Physical; Geosciences, Multidisciplinary SC Physical Geography; Geology GA 364DX UT WOS:000089877700001 ER PT J AU Tucker, MC Reimer, JA Cairns, EJ AF Tucker, MC Reimer, JA Cairns, EJ TI A Li-7 NMR study of lithium insertion into lithium manganese oxide spinel SO ELECTROCHEMICAL AND SOLID STATE LETTERS LA English DT Article ID ELECTRODES; CELLS AB Li-7 magic angle spinning nuclear magnetic resonance was used to observe coexisting cubic and tetragonal phases in Li1+xMn2O4. Cubic phase peaks are observed at 500-580 ppm vs. 1 M LiCl(aq); tetragonal phase peaks are observed around 100 ppm. Cycling Li1+xMn2O4 on the 3 V plateau does not result in significant changes in the cubic phase. A small amount of residual tetragonal phase accounting for similar to 3% of the Li-7 NMR intensity, however, is observed in spinel deep discharged to x = 1 then returned to x = 0. (C) 2000 The Electrochemical Society. S1099-0062(00)05-067-7. All rights reserved. C1 Univ Calif Berkeley, Ernest Orlando Lawerence Berkeley Natl Lab, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Chem Engn, Berkeley, CA 94720 USA. RP Tucker, MC (reprint author), Univ Calif Berkeley, Ernest Orlando Lawerence Berkeley Natl Lab, Berkeley, CA 94720 USA. RI Cairns, Elton/E-8873-2012 OI Cairns, Elton/0000-0002-1179-7591 NR 10 TC 20 Z9 21 U1 1 U2 9 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 65 SOUTH MAIN STREET, PENNINGTON, NJ 08534 USA SN 1099-0062 J9 ELECTROCHEM SOLID ST JI Electrochem. Solid State Lett. PD OCT PY 2000 VL 3 IS 10 BP 463 EP 466 PG 4 WC Electrochemistry; Materials Science, Multidisciplinary SC Electrochemistry; Materials Science GA 344BJ UT WOS:000088737500004 ER PT J AU Yang, XQ Sun, X McBreen, J AF Yang, XQ Sun, X McBreen, J TI Structural changes and thermal stability: in situ X-ray diffraction studies of a new cathode material LiMg0.125Ti0.125Ni0.75O2 SO ELECTROCHEMISTRY COMMUNICATIONS LA English DT Article DE synchrotron X-ray diffraction; LiMg0.125Ti0.125Ni0.75O2; phase transition; lithium batteries ID SECONDARY LITHIUM CELLS; ION CELLS; LIXCOO2; R(3)OVER-BAR-M; LI-1-XNIO2; BATTERIES; SAFETY; LINIO2 AB In situ X-ray diffraction studies in using synchrotron radiation were carried out on a new cathode material LiMg0.125Ti0.125Ni0.75O2 in a charging cell. It had been demonstrated [Y. Gao, M.V. Yakovleva, W.B. Ebner, Electrochem. Solid State Left. 1 (1998) 117] that this new material has thermal stability superior to that of LiNiO2 and LiCo0.2Ni0.8O2 at an over-charged state. In this paper, studies of the relationship between the structural changes during charge and the thermal stability at an over-charged state are presented. For the first time, a hypothesis is proposed to attribute the poor thermal stability of LiNiO2 based materials at overcharged state to the formation of hexagonal phase (H3). An irreversible contraction along crystal 'c' axis usually occurs during the H3 phase formation. According to this hypothesis, improved thermal stability can be obtained by suppressing the formation of H3 phase. The reversibility of the structural changes during overcharge-discharge cycle for this new material is compared with the irreversible structural changes of the LiNiO2 cathode under the same condition. (C) 2000 Published by Elsevier Science S.A. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. RP Yang, XQ (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. NR 12 TC 24 Z9 28 U1 4 U2 22 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 1388-2481 J9 ELECTROCHEM COMMUN JI Electrochem. Commun. PD OCT PY 2000 VL 2 IS 10 BP 733 EP 737 DI 10.1016/S1388-2481(00)00111-9 PG 5 WC Electrochemistry SC Electrochemistry GA 358RP UT WOS:000089571200012 ER PT J AU Isherwood, W Smith, JR Aceves, SM Berry, G Clark, W Johnson, R Das, D Goering, D Seifert, R AF Isherwood, W Smith, JR Aceves, SM Berry, G Clark, W Johnson, R Das, D Goering, D Seifert, R TI Remote power systems with advanced storage technologies for Alaskan villages SO ENERGY LA English DT Article ID TOKAMAK AB This paper presents an analytical optimization of a remote power system for a hypothetical Alaskan village. The analysis considers the potential of generating renewable energy (e.g., wind and solar), along with the possibility of using energy storage to take full advantage of the intermittent renewable sources available to these villages. Storage in the form of either compressed hydrogen or zinc pellets can then provide electricity from hydrogen or zinc-air fuel cells whenever wind or sunlight are low. The renewable system is added on to the existing generation system, which is based on diesel engines. Results indicate that significant reductions in fossil fuel consumption in these remote communities are cost effective using renewable energy combined with advanced energy storage devices. A hybrid energy system for the hypothetical village can reduce consumption of diesel fuel by about 50% with annual cost savings of about 30% by adding wind turbines to the existing diesel generators. Adding energy storage devices can further reduce fuel use, and depending on the economic conditions potentially reduce life-cycle costs. With optimized energy storage, use of the diesel gensets can be reduced to almost zero, with the existing equipment only maintained for added reliability. However, about one quarter of the original fuel is still used for heating purposes. Published by Elsevier Science Ltd. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Univ Alaska Fairbanks, Dept Mech Engn, Fairbanks, AK 99775 USA. RP Isherwood, W (reprint author), Univ Calif Lawrence Livermore Natl Lab, 7000 East Ave L-530, Livermore, CA 94551 USA. RI aceves, salvador/G-9052-2011 OI aceves, salvador/0000-0001-5687-7256 NR 22 TC 36 Z9 37 U1 1 U2 8 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0360-5442 J9 ENERGY JI Energy PD OCT PY 2000 VL 25 IS 10 BP 1005 EP 1020 DI 10.1016/S0360-5442(00)00028-1 PG 16 WC Thermodynamics; Energy & Fuels SC Thermodynamics; Energy & Fuels GA 353VE UT WOS:000089295500006 ER PT J AU Tonn, B Martin, M AF Tonn, B Martin, M TI Industrial energy efficiency decision making SO ENERGY POLICY LA English DT Article AB This paper presents a model to describe an industrial firm's energy efficiency decision making over time. The model posits seven stages, which range from no energy savings decision making to energy efficiency program implementation to steady state energy efficiency decision making. It is hypothesized that government energy-efficiency programs, such as the Industrial Assessment Center (IAC) Program funded by the US Department of Energy (DOE), can accelerate the speed industrial firms move through the model's seven stages. Data were collected about firms' stages in the model before and after receiving one of the three IAC benefits: a direct energy assessment; the employ of a student alumnus of the IAC Program; or use of energy efficiency information from an IAC website. It was found that each IAC benefit is associated with a significant positive change in firms' energy efficiency decision making within a relatively short period of time. (C) 2000 Elsevier Science Ltd. All rights reserved. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Tonn, B (reprint author), Oak Ridge Natl Lab, Bldg 4500N,POB 2008, Oak Ridge, TN 37831 USA. NR 26 TC 16 Z9 16 U1 0 U2 4 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0301-4215 J9 ENERG POLICY JI Energy Policy PD OCT PY 2000 VL 28 IS 12 BP 831 EP 843 DI 10.1016/S0301-4215(00)00068-9 PG 13 WC Energy & Fuels; Environmental Sciences; Environmental Studies SC Energy & Fuels; Environmental Sciences & Ecology GA 343DP UT WOS:000088686700002 ER PT J AU Solomon, BD Lee, R AF Solomon, BD Lee, R TI Emissions trading systems and environmental justice SO ENVIRONMENT LA English DT Article ID GLOBAL WARMING POLICY; SPATIAL EQUITY; UNITED-STATES; AIR EMISSIONS; LOS-ANGELES; LESSONS; PERMITS; MARKET C1 Michigan Technol Univ, Dept Social Sci, Houghton, MI 49931 USA. Oak Ridge Natl Lab, Ctr Energy & Environm Anal, Oak Ridge, TN USA. RP Solomon, BD (reprint author), Michigan Technol Univ, Dept Social Sci, Houghton, MI 49931 USA. NR 53 TC 13 Z9 14 U1 2 U2 6 PU HELDREF PUBLICATIONS PI WASHINGTON PA 1319 EIGHTEENTH ST NW, WASHINGTON, DC 20036-1802 USA SN 0013-9157 J9 ENVIRONMENT JI Environment PD OCT PY 2000 VL 42 IS 8 BP 32 EP 45 PG 14 WC Environmental Sciences; Environmental Studies SC Environmental Sciences & Ecology GA 358PP UT WOS:000089566700005 ER PT J AU Paez, A Gebre, GM Gonzalez, ME Tschaplinski, TJ AF Paez, A Gebre, GM Gonzalez, ME Tschaplinski, TJ TI Growth, soluble carbohydrates, and aloin concentration of Aloe vera plants exposed to three irradiance levels SO ENVIRONMENTAL AND EXPERIMENTAL BOTANY LA English DT Article DE Aloe vera; aloin; carbon allocation; partitioning; irradiance; carbohydrates ID PHENOLIC-COMPOUNDS; LEAF-EXUDATE; LEAVES; SHADE AB Research was conducted on Aloe vera, a traditional medicinal plant, to investigate the effects of light on growth, carbon allocation, and the concentrations of organic solutes, including soluble carbohydrates and aloin. The plants were vegetatively propagated and grown under three irradiances: full sunlight, partial (30% full sunlight), and deep shade (10% full sunlight) for 12-18 months. After 1 year of growth, five plants from each treatment were harvested to determine total above- and below ground dry mass. Four plants from the full sunlight and the partial shade treatments were harvested after 18 months to assess the soluble carbohydrate, organic acid and aloin concentrations of the clear parenchyma gel and the yellow leaf exudate, separately. Plants grown under full sunlight produced more numerous and larger axillary shoots, resulting in twice the total dry mass than those grown under partial shade. The dry mass of the plants grown under deep shade was 8.6% that of plants grown under full sunlight. Partial shade increased the number and length of leaves produced on the primary shoot, but leaf dry mass was still reduced to 66% of that in full sunlight. In contrast, partial and deep shade reduced root dry mass to 28 and 13%, respectively, of that under full sunlight, indicating that carbon allocation to roots was restricted under low light conditions. When plants were sampled 6 months later, there were only minor treatment effects on the concentration of soluble carbohydrates and aloin in the leaf exudate and gel. Soluble carbohydrate concentrations were greater in the gel than in the exudate, with glucose the most abundant soluble carbohydrate. Aloin was present only in the leaf exudate and higher irradiance did not induce a higher concentration. Limitation in light availability primarily affected total dry mass production and allocation, without substantial effects on either primary or secondary carbon metabolites. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. Univ Zulia, Fac Ciencias, Dept Biol, Lab Ecofisiol, Maracaibo 4011, Venezuela. Colorado State Univ, Dept Bioagr Sci & Pest Management, Ft Collins, CO 80523 USA. RP Tschaplinski, TJ (reprint author), Oak Ridge Natl Lab, Div Environm Sci, POB 2008, Oak Ridge, TN 37831 USA. OI Tschaplinski, Timothy/0000-0002-9540-6622 NR 20 TC 31 Z9 42 U1 1 U2 13 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0098-8472 J9 ENVIRON EXP BOT JI Environ. Exp. Bot. PD OCT PY 2000 VL 44 IS 2 BP 133 EP 139 DI 10.1016/S0098-8472(00)00062-9 PG 7 WC Plant Sciences; Environmental Sciences SC Plant Sciences; Environmental Sciences & Ecology GA 353UZ UT WOS:000089295000005 ER PT J AU Huff, DD AF Huff, DD TI A 35-year history of Sr-90 releases from a radioactive-waste burial ground SO ENVIRONMENTAL GEOLOGY LA English DT Article DE radioactive; remedial action; radiostrontium; burial ground; source control AB Data from a radioactive waste disposal area at Oak Ridge National Laboratory suggest that releases depend on site hydrology and waste containment. Loss of packaging integrity has apparently caused episodic increases in Sr-90 source strength, followed by gradual reduction as runoff carries contaminants away. Most flow and transport occurs during January-April storms in response to site hydrology. Diversion of runoff from undisturbed areas upstream of the waste site (1983) reduced flow through the site by more than 65% and annual Sr-90 release by more than 45%. However, between 1983 and 1994, increases in Sr-90 source strength have partially offset the diversion effectiveness. Selective source control in 1996 further reduced annual Sr-90 releases by more than 30% in the first two years, compared with pre-treatment conditions. The effectiveness of the grouting treatment should increase over the next 5-10 years, if new 90Sr sources are insignificant. C1 Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. RP Huff, DD (reprint author), Oak Ridge Natl Lab, Div Environm Sci, POB 2008, Oak Ridge, TN 37831 USA. NR 11 TC 2 Z9 2 U1 1 U2 1 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0943-0105 J9 ENVIRON GEOL JI Environ. Geol. PD OCT PY 2000 VL 39 IS 11 BP 1275 EP 1285 PG 11 WC Environmental Sciences; Geosciences, Multidisciplinary; Water Resources SC Environmental Sciences & Ecology; Geology; Water Resources GA 371RJ UT WOS:000165191700007 ER PT J AU Phillips, DH Gu, B Watson, DB Roh, Y Liang, L Lee, SY AF Phillips, DH Gu, B Watson, DB Roh, Y Liang, L Lee, SY TI Performance evaluation of a zerovalent iron reactive barrier: Mineralogical characteristics SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Article ID ZERO-VALENT IRON; PRECIPITATION; COLUMNS; METAL; OXIDE AB There is a limited amount of information about the effects of mineral precipitates and corrosion on the lifespan and long-term performance of in situ Fe-o reactive barriers. The objectives of this paper are (1) to investigate mineral precipitates through an in situ permeable Fe-o reactive barrier and (2) to examine the cementation and corrosion of Fe-o filings in order to estimate the lifespan of this barrier. This field scale barrier (225' long x 2' wide x 31' deep) has been installed in order to remove uranium from contaminated groundwater at the Y-12 plant site, Oak Ridge, TN. According to XRD and SEM-EDX analysis of core samples recovered from the Fe-o portion of the barrier, iron oxyhydroxides were found throughout, while aragonite, siderite, and FeS occurred predominantly in the shallow portion. Additionally, aragonite and FeS were present in upgradient deeper zone where groundwater first enters the Fe-o section of the barrier. After 15 months in the barrier, most of the Fe-o filings in the core samples were loose, and a little corrosion of Fe-o filings was observed in most of the barrier. However, larger amounts of corrosion (similar to 10-150 mu m thick corrosion rinds) occurred on cemented iron particles where groundwater first enters the barrier. Bicarbonate/ carbonate concentrations were high in this section of the barrier. Byproducts of this corrosion, iron oxyhydroxides, were the primary binding material in the cementation. Also, aragonite acted as a binding material to a lesser extent, while amorphous FeS occurred as coatings and infilings. Thin corrosion rinds (2-50 mu m thick) were also found on the uncemented individual Fe-o filings in the same area of the cementation. If corrosion continues, the estimated lifespan of Fe-o filings in the more corroded sections is 5 to 10 years, while the Fe-o filings in the rest of the barrier perhaps would last longer than 15 years. The mineral precipitates on the Fe-o filing surfaces may hinder this corrosion but they may also decrease reactive surfaces. This research shows that precipitation will vary across a single reactive barrier and that greater corrosion and subsequent cementation of the filings may occur where groundwater first enters the Fe-o section of the barrier. C1 Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. RP Phillips, DH (reprint author), Oak Ridge Natl Lab, Div Environm Sci, POB 2008,Bldg 1505, Oak Ridge, TN 37831 USA. EM phillipsdh@ornl.gov RI Phillips, Debra/F-1828-2010; Gu, Baohua/B-9511-2012; Liang, Liyuan/O-7213-2014; Watson, David/C-3256-2016 OI Phillips, Debra/0000-0001-8548-7409; Gu, Baohua/0000-0002-7299-2956; Liang, Liyuan/0000-0003-1338-0324; Watson, David/0000-0002-4972-4136 NR 30 TC 177 Z9 182 U1 3 U2 52 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 OCT 1 PY 2000 VL 34 IS 19 BP 4169 EP 4176 DI 10.1021/es001005z PG 8 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 359HB UT WOS:000089604500034 ER PT J AU Palmer, CD AF Palmer, CD TI Precipitates in a Cr(VI)-contaminated concrete SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Article ID HEXAVALENT CHROMIUM; TRICALCIUM SILICATE; SOLID-SOLUTION; ETTRINGITE; HYDRATION; 3CAO.AL2O3.3CASO4.32H2O; IMMOBILIZATION; SOLUBILITY; PHASES; PASTES AB Examination of Cr(VI)-contaminated concrete from a former hard-chrome plating shop revealed the presence of long, thin crystals varying from white to bright yellow. Many of the crystals examined by scanning electron microscopy (SEM) were acicular and 25-100 mu m in length and 1-15 mu m wide. The composition, determined by energy-dispersive X-ray spectroscopy, morphology, and d spacings, measured by electron diffraction, identifies these crystals as chromate enriched ettringite (Ca6Al2((S,- CT)O-4)(2)(OH)(12). 26H(2)O) With the mole fraction of CrO42- in the SO42- position being 0.41 and 0.72. A nearly pure CrO42- - hydrocalumite (3CaO . Al2O3. CaCrO4. nH(2)O) is also observed. Some of these crystals appear to be pseudomorphs of ettringite. The CrO42--hydrocalumite crystals are coated with smaller acicular crystals that are most likely solid solutions between Si-ettringite (Ca6Al2(SiO3)(3)(OH)(12). 26H(2)O) and CrO42--ettringite. These crystals are bound together by an amorphous appearing SiO2 phase. Ca-silicate-hydrate gel (CSH) has precipitated around ettringite-group crystals containing chromium indicating that some CSH formation occurred after contamination of the concrete. C1 Portland State Univ, Portland, OR 97201 USA. RP Palmer, CD (reprint author), Idaho Natl Engn & Environm Lab, POB 1625, Idaho Falls, ID 83415 USA. NR 47 TC 34 Z9 35 U1 2 U2 18 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 OCT 1 PY 2000 VL 34 IS 19 BP 4185 EP 4192 DI 10.1021/es991089f PG 8 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 359HB UT WOS:000089604500036 ER PT J AU Hopkins, WA AF Hopkins, WA TI Reptile toxicology: Challenges and opportunities on the last frontier in vertebrate ecotoxicology SO ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY LA English DT Letter C1 Savannah River Ecol Lab, Aiken, SC 29801 USA. RP Hopkins, WA (reprint author), Savannah River Ecol Lab, Drawer E, Aiken, SC 29801 USA. NR 7 TC 86 Z9 88 U1 3 U2 23 PU SETAC PI PENSACOLA PA 1010 NORTH 12TH AVE, PENSACOLA, FL 32501-3367 USA SN 0730-7268 J9 ENVIRON TOXICOL CHEM JI Environ. Toxicol. Chem. PD OCT PY 2000 VL 19 IS 10 BP 2391 EP 2393 DI 10.1897/1551-5028(2000)019<2391:RTCAOO>2.3.CO;2 PG 3 WC Environmental Sciences; Toxicology SC Environmental Sciences & Ecology; Toxicology GA 360PN UT WOS:000089676600001 ER PT J AU Gorgen, A Hubel, H Ward, D Chmel, S Clark, RM Cromaz, M Diamond, RM Fallon, P Hauschild, K Lane, GJ Lee, IY Macchiavelli, AO Vetter, K AF Gorgen, A Hubel, H Ward, D Chmel, S Clark, RM Cromaz, M Diamond, RM Fallon, P Hauschild, K Lane, GJ Lee, IY Macchiavelli, AO Vetter, K TI Search for magnetic rotation in Pb-202 and Pb-203 SO EUROPEAN PHYSICAL JOURNAL A LA English DT Article ID SHEARS BANDS; NUCLEI; LIFETIMES; MECHANISM; MODEL AB High-spin states in Pb-202 and Pb-203 hare been investigated by in-beam gamma -ray spectroscopy following the reaction Pt-198(Be-9,xn). A search for magnetic rotational bands in these isotopes confirmed one of the two bands previously assigned to Pb-202 and revealed a new band in this isotope. No evidence for magnetic rotation has been found in Pb-203. C1 Univ Bonn, Inst Strahlen & Kernphys, D-53115 Bonn, Germany. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Gorgen, A (reprint author), Univ Bonn, Inst Strahlen & Kernphys, Nussallee 14-16, D-53115 Bonn, Germany. RI Hauschild, Karl/A-6726-2009; Lane, Gregory/A-7570-2011; OI Lane, Gregory/0000-0003-2244-182X; Gorgen, Andreas/0000-0003-1916-9941 NR 17 TC 2 Z9 2 U1 0 U2 0 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 1434-6001 J9 EUR PHYS J A JI Eur. Phys. J. A PD OCT PY 2000 VL 9 IS 2 BP 161 EP 164 DI 10.1007/s100500070032 PG 4 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 387ZA UT WOS:000166151900004 ER PT J AU Rzaca-Urban, T Urban, W Kaczor, A Durell, JL Leddy, MJ Jones, MA Phillips, WR Smith, AG Varley, BJ Ahmad, I Morss, LR Bentaleb, H Lubkiewicz, E Schulz, N AF Rzaca-Urban, T Urban, W Kaczor, A Durell, JL Leddy, MJ Jones, MA Phillips, WR Smith, AG Varley, BJ Ahmad, I Morss, LR Bentaleb, H Lubkiewicz, E Schulz, N TI Shapes of the neutron-rich Kr88-94 nuclei SO EUROPEAN PHYSICAL JOURNAL A LA English DT Article ID SPECTROSCOPY AB Neutron-rich, Kr88-94 nuclei, populated in spontaneous fission of Cm-248, have been studied with EUROGAM 2, by measuring prompt gamma -rays. Many new excited states in even-even Kr isotopes have been identified. For the first time spins and parities were determined experimentally in these nuclei. Our results indicate that the quadrupole deformation of Kr isotopes will appear only above N = 58, as observed in Sr and Zr nuclei. The newly found 3(-) level at 1506.4 keV in Kr-90 suggests the exsistence of a new region of increased octupole correlations, probably associated with the v(d(5/2)h(11/2)) pair of Deltal = Deltaj = 3 orbitals. C1 Univ Warsaw, Inst Expt Phys, PL-00681 Warsaw, Poland. Univ Manchester, Schuster Lab, Dept Phys & Astron, Manchester M13 9PL, Lancs, England. Argonne Natl Lab, Argonne, IL 60439 USA. Univ Strasbourg 1, F-67037 Strasbourg, France. IN2P3, Inst Rech Subatom, CNRS, UMR 7500, F-67037 Strasbourg, France. RP Rzaca-Urban, T (reprint author), Univ Warsaw, Inst Expt Phys, Ul Hoza 69, PL-00681 Warsaw, Poland. NR 14 TC 35 Z9 35 U1 0 U2 2 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 1434-6001 J9 EUR PHYS J A JI Eur. Phys. J. A PD OCT PY 2000 VL 9 IS 2 BP 165 EP 169 DI 10.1007/s100500070033 PG 5 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 387ZA UT WOS:000166151900005 ER PT J AU Wilson, AN Beausang, CW Amzal, N Appelbe, DE Asztalos, S Butler, PA Clark, RM Fallon, P Macchiavelli, AO AF Wilson, AN Beausang, CW Amzal, N Appelbe, DE Asztalos, S Butler, PA Clark, RM Fallon, P Macchiavelli, AO TI High-spin states following multi-nucleon transfer SO EUROPEAN PHYSICAL JOURNAL A LA English DT Article ID SUPERDEFORMATION; ISOTOPES AB High-spin states in neutron-rich nuclei, populated following deep-inelastic multi-nucleon transfer, have been studied using the GAMMASPHERE array at the LBNL, USA. A Ni-64 beam at an energy similar to 15% above the Coulomb barrier was incident upon a thick Pb-208 target, leading to the population of more than 130 different nuclei. The strongest channels correspond to nuclei close to the projectile and target, although transfer of up to 50 nucleons has been observed. New high-spin states in neutron-rich Fe-60,Fe-62 and Zn-68,Zn-70,Zn-72 nuclei have been observed. Some limitations of this method of high-spin spectroscopy are discussed, including the apparent difficulty of populating odd-odd and odd-even isotopes via this type of reaction. The data have been searched for superdeformed (SD) states in the A = 190-200 region, but no evidence for their presence has been found. C1 Yale Univ, Wright Nucl Struct Lab, New Haven, CT 06520 USA. Univ York, Dept Phys, York YO10 5DD, N Yorkshire, England. Univ Liverpool, Oliver Lodge Lab, Liverpool L69 3BX, Merseyside, England. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Wilson, AN (reprint author), Yale Univ, Wright Nucl Struct Lab, 272 Whitney Ave, New Haven, CT 06520 USA. OI Wilson, Anna/0000-0001-6928-1689; Butler, Peter/0000-0001-6080-9205 NR 20 TC 25 Z9 25 U1 0 U2 2 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 1434-6001 J9 EUR PHYS J A JI Eur. Phys. J. A PD OCT PY 2000 VL 9 IS 2 BP 183 EP 189 DI 10.1007/s100500070035 PG 7 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 387ZA UT WOS:000166151900007 ER PT J AU Kautzsch, T Walters, WB Hannawald, M Kratz, KL Mishin, VI Fedoseyev, VN Bohmer, W Jading, Y Van Duppen, P Pfeiffer, B Wohr, A Moller, P Klockl, I Sebastian, V Koster, U Koizumi, M Lettry, J Ravn, HL AF Kautzsch, T Walters, WB Hannawald, M Kratz, KL Mishin, VI Fedoseyev, VN Bohmer, W Jading, Y Van Duppen, P Pfeiffer, B Wohr, A Moller, P Klockl, I Sebastian, V Koster, U Koizumi, M Lettry, J Ravn, HL CA ISOLDE Collaboration TI New states in heavy Cd isotopes and evidence for weakening of the N=82 shell structure SO EUROPEAN PHYSICAL JOURNAL A LA English DT Article ID LASER ION-SOURCE; ASTROPHYSICAL R-PROCESS; NUCLEAR-MASS FORMULA; NEUTRON-DRIP-LINE; MEAN-FIELD THEORY; EVEN-EVEN NUCLEI; PROCESS ABUNDANCES; TEMPERATURES; STABILITY; DECAY AB A chemically selective laser ion source has been used in a beta -decay study of heavy Ag isotopes into even-even Cd nuclides. Gamma-spectroscopic techniques in time-resolving event-by-event and multiscaling modes have permitted the identification of the first 2(+) and 4(+) levels in Cd-126(78), Cd-128(80), and tentatively the 2(+) state in Cd-130(82). From a comparison of these new states in Cd-48 with the E(2(+)) and E(4(+))/E(2(+)) level systematics of Pd-46 and Te-52 isotopes and several recent model predictions, possible evidence for a weakening of the spherical N = 82 neutron-shell below double-magic Sn-132 is obtained. C1 Univ Mainz, Inst Kernchem, D-55128 Mainz, Germany. Univ Maryland, Dept Chem, College Pk, MD 20742 USA. Russian Acad Sci, Inst Spect, RUS-142092 Troitzk, Russia. CERN, CH-1211 Geneva 23, Switzerland. Univ Louvain, Inst Kern & Stralingsfys, B-3001 Heverlee, Belgium. Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Univ Mainz, Inst Phys, D-55099 Mainz, Germany. Tech Univ Munich, Dept Phys, D-85748 Garching, Germany. Japan Atom Energy Res Inst, Takasaki, Gumma 37012, Japan. RP Kautzsch, T (reprint author), Univ Mainz, Inst Kernchem, D-55128 Mainz, Germany. NR 44 TC 53 Z9 53 U1 0 U2 3 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 1434-6001 J9 EUR PHYS J A JI Eur. Phys. J. A PD OCT PY 2000 VL 9 IS 2 BP 201 EP 206 DI 10.1007/s100500070038 PG 6 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 387ZA UT WOS:000166151900010 ER PT J AU Adams, MR Aderholz, M Aid, S Anthony, PL Ashery, D Averill, DA Baker, MD Baller, BR Banerjee, A Bhatti, AA Bratzler, U Braun, HM Carroll, TJ Clark, HL Conrad, JM Davisson, R Derado, I Dietrich, FS Dougherty, W Dreyer, T Eckardt, V Ecker, U Erdmann, M Fang, GY Figiel, J Finlay, RW Gebauer, HJ Geesaman, DF Griffioen, KA Guo, RS Haas, J Halliwell, C Hantke, D Hicks, KH Jackson, HE Jancso, G Jansen, DM Jin, Z Kadija, K Kaufmann, S Kennedy, RD Kinney, ER Kobrak, HGE Kotwal, AV Kunori, S Lenski, M Lord, JJ Lubatti, HJ McLeod, D Madden, P Manz, A Melanson, H Michael, DG Montgomery, HE Morfin, JG Nickerson, RB Novak, J Olkiewicz, K Osborne, L Otten, R Papavassiliou, V Pawlik, B Pipkin, FM Potterveld, DH Roser, A Ryan, JJ Salgado, CW Schellman, H Schmitt, M Schmitz, N Siegert, G Skuja, A Snow, GA Soldner-Rembold, S Spentzouris, P Stopa, P Swanson, RA Pop, VT Venkataramania, H Wilhelm, M Wilson, R Wittek, W Wolbers, SA Zghiche, A Zhao, T AF Adams, MR Aderholz, M Aid, S Anthony, PL Ashery, D Averill, DA Baker, MD Baller, BR Banerjee, A Bhatti, AA Bratzler, U Braun, HM Carroll, TJ Clark, HL Conrad, JM Davisson, R Derado, I Dietrich, FS Dougherty, W Dreyer, T Eckardt, V Ecker, U Erdmann, M Fang, GY Figiel, J Finlay, RW Gebauer, HJ Geesaman, DF Griffioen, KA Guo, RS Haas, J Halliwell, C Hantke, D Hicks, KH Jackson, HE Jancso, G Jansen, DM Jin, Z Kadija, K Kaufmann, S Kennedy, RD Kinney, ER Kobrak, HGE Kotwal, AV Kunori, S Lenski, M Lord, JJ Lubatti, HJ McLeod, D Madden, P Manz, A Melanson, H Michael, DG Montgomery, HE Morfin, JG Nickerson, RB Novak, J Olkiewicz, K Osborne, L Otten, R Papavassiliou, V Pawlik, B Pipkin, FM Potterveld, DH Roser, A Ryan, JJ Salgado, CW Schellman, H Schmitt, M Schmitz, N Siegert, G Skuja, A Snow, GA Soldner-Rembold, S Spentzouris, P Stopa, P Swanson, RA Pop, VT Venkataramania, H Wilhelm, M Wilson, R Wittek, W Wolbers, SA Zghiche, A Zhao, T TI Lambda and (Lambda)over-bar polarization from deep in elastic muon scattering SO EUROPEAN PHYSICAL JOURNAL C LA English DT Article ID NEUTRAL STRANGE PARTICLES; STRUCTURE FUNCTIONS G(1); PROTON INTERACTIONS; FRAGMENTATION; DEUTERON; BARYONS; NUCLEON; DECAYS AB We report results of the first measurements of Lambda and <()over bar> polarization produced in deep inelastic polarized muon scattering on the nucleon. The results are consistent with an expected trend towards positive polarization with increasing x(F). The polarizations of Lambda and <()over tilde> appear to have opposite signs. A large negative polarization for Lambda at low positive x(F) is observed and is not explained by existing models. A possible interpretation is presented. C1 Univ Illinois, Chicago, IL 60680 USA. Univ Freiburg, Freiburg, Germany. Argonne Natl Lab, Argonne, IL 60439 USA. Univ Calif San Diego, La Jolla, CA 92093 USA. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Harvard Univ, Cambridge, MA 02138 USA. KFKI Res Inst Particle & Nucl Phys, H-1525 Budapest, Hungary. Inst Phys Nucl, Krakow, Poland. Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Univ Maryland, College Pk, MD 20742 USA. MIT, Cambridge, MA 02139 USA. Max Planck Inst Phys & Astrophys, D-80805 Munich, Germany. Northwestern Univ, Evanston, IL 60208 USA. Ohio Univ, Athens, OH 45701 USA. Univ Penn, Philadelphia, PA 19104 USA. Univ Washington, Seattle, WA 98195 USA. Univ Wuppertal, Wuppertal, Germany. Tel Aviv Univ, IL-69978 Tel Aviv, Israel. RP Adams, MR (reprint author), Univ Illinois, Chicago, IL 60680 USA. NR 24 TC 53 Z9 53 U1 0 U2 0 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1434-6044 EI 1434-6052 J9 EUR PHYS J C JI Eur. Phys. J. C PD OCT PY 2000 VL 17 IS 2 BP 263 EP 267 DI 10.1007/s100520000493 PG 5 WC Physics, Particles & Fields SC Physics GA 370TE UT WOS:000165137700006 ER PT J AU Benayoun, M DelBuono, L Leruste, P O'Connell, HB AF Benayoun, M DelBuono, L Leruste, P O'Connell, HB TI An effective approach to VMD at one loop order and the departures from ideal mixing for vector mesons SO EUROPEAN PHYSICAL JOURNAL C LA English DT Article ID HIDDEN LOCAL SYMMETRIES; DYNAMICAL GAUGE BOSONS; PION FORM-FACTOR; RADIATIVE DECAYS; RHO-MESON; PARAMETRIZATION; BREAKING; PHYSICS; REGION; QCD AB We examine the mechanisms producing departures front ideal mixing for vector mesons within the context; of the Ridden Local Symmetry (HLS) model. We show that kaon loop transitions between the ideal combinations of the omega and phi mesons necessitate a field transformation in order to get the mass eigenstates. It is shown that this transformation is close to a rotation for processes involving, like meson decays, on-shell omega and phi mesons. The HLS model predicts a momentum dependent, slowly varying mixing angle between the ideal states. We examine numerically the consequences of this for radiative and leptonic decays of light mesons. The mean omega - phi mixing angle is found smaller than its ideal value; this is exhibited separately in radiative and in leptonic decays. Effects of nonet symmetry breaking in the vector sector are compared to those produced hy the field rotation implied by the HLS model. C1 Univ Paris 06, LPNHE, Paris, France. Univ Paris 07, IN2P3, Paris, France. Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Benayoun, M (reprint author), Univ Paris 06, LPNHE, Paris, France. OI O'Connell, Heath/0000-0002-1895-5310 NR 40 TC 19 Z9 19 U1 0 U2 0 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1434-6044 EI 1434-6052 J9 EUR PHYS J C JI Eur. Phys. J. C PD OCT PY 2000 VL 17 IS 2 BP 303 EP 321 DI 10.1007/s100520000463 PG 19 WC Physics, Particles & Fields SC Physics GA 370TE UT WOS:000165137700010 ER PT J AU Belyaev, A Drees, M Mizukoshi, JK AF Belyaev, A Drees, M Mizukoshi, JK TI Supersymmetric Higgs boson pair production: Discovery prospects at hadron colliders SO EUROPEAN PHYSICAL JOURNAL C LA English DT Article ID RADIATIVE-CORRECTIONS; MINIMAL SUPERGRAVITY; STANDARD MODEL; LHC; COLLISIONS; TEVATRON; SEARCH; MASS; SCATTERING; PHYSICS AB We study the potential of hadron colliders in the search for the pair production of neutral Higgs bosons in the framework of the minimal supersymmetric standard model. We perform a detailed signal and background analysis, working out efficient kinematical cuts for the extraction of the signal. The important role of squark loop contributions to the signal is re-emphasized. If the signal is sufficiently enhanced by these contributions, it could even be observable at the next run of the upgraded Tevatron collider in the near future. At the LHC the pair production of light and heavy Higgs bosons might be detectable simultaneously. C1 Univ Estadual Paulista, Inst Fis Teor, BR-01405900 Sao Paulo, Brazil. Moscow MV Lomonosov State Univ, Skobeltsyn Inst Nucl Phys, Moscow 119899, Russia. Tech Univ Munich, Dept Phys, D-85748 Garching, Germany. Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Belyaev, A (reprint author), Univ Estadual Paulista, Inst Fis Teor, Rua Pamplona 145, BR-01405900 Sao Paulo, Brazil. OI Belyaev, Alexander/0000-0002-1733-4408 NR 43 TC 23 Z9 23 U1 0 U2 0 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1434-6044 EI 1434-6052 J9 EUR PHYS J C JI Eur. Phys. J. C PD OCT PY 2000 VL 17 IS 2 BP 337 EP 351 DI 10.1007/s100520000436 PG 15 WC Physics, Particles & Fields SC Physics GA 370TE UT WOS:000165137700012 ER PT J AU Muller, P Bushaw, BA Nortershauser, W Wendt, K AF Muller, P Bushaw, BA Nortershauser, W Wendt, K TI Isotope shifts and hyperfine structure in calcium 4snp P-1(1) and 4snf F Rydberg states SO EUROPEAN PHYSICAL JOURNAL D LA English DT Article ID IONIZATION SPECTROSCOPY; LASER SPECTROSCOPY; CA-41; TRANSITIONS; CESIUM; NP; NF AB Isotope shifts and hyperfine structure have been measured in 4snp, P-1(1) and 4snf F Rydberg states for all stable calcium isotopes and the radioisotope Ca-41 using high-resolution laser spectroscopy. Triple-resonance excitation via 4s(21)S(0) --> 4s4p P-1(1) --> 4s4d D-1(2) --> Rydberg state was followed by photoionization with a CO2 laser and mass selective ion detection. Isotope shifts for the even-mass isotopes have been analyzed to derive specific mass shift and field shift factors. The apparent isotope shifts for Ca-41 and Ca-43 exhibit anomalous values that are n-dependent. This is interpreted in terms of hyperfine-induced fine-structure mixing, which becomes very pronounced when singlet-triplet fine-structure splitting is comparable to the hyperfine interaction energy. Measurements of fine-structure splittings for the predominant isotope Ca-40 have been used as input parameters for theoretical calculation of the perturbed hyperfine structure. Results obtained by diagonalizing the second-order hyperfine interaction matrices agree very well with experimentally observed spectra. These measurements allow the evaluation of highly selective and sensitive methods for the detection of the rare Ca-41 isotope. C1 Univ Mainz, Inst Phys, D-55099 Mainz, Germany. Pacific NW Natl Lab, Richland, WA 99352 USA. RP Muller, P (reprint author), Univ Mainz, Inst Phys, D-55099 Mainz, Germany. RI Mueller, Peter/E-4408-2011; Wendt, Klaus/D-7306-2011; Nortershauser, Wilfried/A-6671-2013 OI Mueller, Peter/0000-0002-8544-8191; Wendt, Klaus/0000-0002-9033-9336; Nortershauser, Wilfried/0000-0001-7432-3687 NR 29 TC 20 Z9 20 U1 0 U2 2 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 1434-6060 J9 EUR PHYS J D JI Eur. Phys. J. D PD OCT PY 2000 VL 12 IS 1 BP 33 EP 44 DI 10.1007/s100530070040 PG 12 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 357RH UT WOS:000089514300006 ER PT J AU Ivanova, K Ausloos, M Clothiaux, EE Ackerman, TP AF Ivanova, K Ausloos, M Clothiaux, EE Ackerman, TP TI Break-up of stratus cloud structure predicted from non-Brownian motion liquid water and brightness temperature fluctuations SO EUROPHYSICS LETTERS LA English DT Article ID JONES-INDUSTRIAL-AVERAGE; USD EXCHANGE-RATE; SCALE-INVARIANCE; CRITICALITY; VARIABILITY; PRICE; MODEL AB The Detrended Fluctuation Analysis statistical method is applied to microwave radiometer and infrared thermometer radiance data in order to examine stratus cloud dynamics. The existence of long-range power law correlations in stratus cloud liquid water path and radiance (brightness temperature) fluctuations is demonstrated to occur over about a two-hour period. Moreover, using a finite-size (time) interval window, a change from non-Brownian to Brownian fluctuation regimes is clearly shown to define the cloud structure changes. C1 Penn State Univ, Dept Meteorol, University Pk, PA 16802 USA. Bulgarian Acad Sci, Inst Elect, BU-1784 Sofia, Bulgaria. Univ Liege, Inst Phys B5, SUPRAS, B-4000 Liege, Belgium. Univ Liege, Inst Phys B5, GRASP, B-4000 Liege, Belgium. US DOE, Pacific NW Natl Lab, Richland, WA 99352 USA. RP Ivanova, K (reprint author), Penn State Univ, Dept Meteorol, 503 Walker Bldg, University Pk, PA 16802 USA. NR 24 TC 40 Z9 42 U1 0 U2 0 PU E D P SCIENCES PI LES ULIS CEDEXA PA 7, AVE DU HOGGAR, PARC D ACTIVITES COURTABOEUF, BP 112, F-91944 LES ULIS CEDEXA, FRANCE SN 0295-5075 J9 EUROPHYS LETT JI Europhys. Lett. PD OCT PY 2000 VL 52 IS 1 BP 40 EP 46 DI 10.1209/epl/i2000-00401-5 PG 7 WC Physics, Multidisciplinary SC Physics GA 362RH UT WOS:000089791700007 ER PT J AU Eberling, JL Pivirotto, P Bringas, J Bankiewicz, KS AF Eberling, JL Pivirotto, P Bringas, J Bankiewicz, KS TI Tremor is associated with PET measures of nigrostriatal dopamine function in MPTP-lesioned monkeys SO EXPERIMENTAL NEUROLOGY LA English DT Article DE MPTP; tremor; Parkinson's disease; PET; primate; dopamine ID POSITRON EMISSION TOMOGRAPHY; PARKINSONS-DISEASE; BRAIN DOPAMINE; REST TREMOR; METABOLISM; SYMPTOMS; PRIMATES; SYSTEM; MODEL AB Unilateral intracarotid artery (ICA) MPTP infusion, along with sequential systemic doses of MPTP, produces near complete degeneration of the nigrostriatal pathway on the side of infusion (ipsilateral) and variable levels of damage in the contralateral hemisphere accompanied by varying levels of parkinsonism (overlesioned hemiparkinsonian model). Positron emission tomography and the dopamine (DA) metabolism tracer [F-18]6-fluoro-L-m-tyrosine (FMT) were used to evaluate the relationship between DA metabolism and clinical features of parkinsonism in 14 overlesioned hemiparkinsonian monkeys. Monkeys were rated on a parkinsonian scale that included ratings of bradykinesia, fine motor skills (FMS), and rest tremor. Because the monkeys tended to show more severe clinical signs on the side of the body contralateral to ICA MPTP infusion, we calculated asymmetry scores for each of the clinical features as well as for FMT uptake (K-i) in the caudate and putamen. Tremor asymmetry was associated with FMT uptake asymmetry in the putamen. No such relationship was observed for FMS or bradykinesia. The overall severity of tremor (mild, moderate/severe) was associated with FMT uptake in the caudate and putamen. Postmortem biochemical analysis for a subset of monkeys showed that the monkeys with moderate/severe tremor had significantly lower DA levels in both caudate and putamen than those with mild tremor. In addition, K-i values were significantly correlated with DA levels in both caudate and putamen. These findings support the idea that nigrostriatal degeneration contributes to rest tremor. (C) 2000 Academic Press. C1 Lawrence Berkeley Lab, Ctr Funct Imaging, Berkeley, CA 94720 USA. Univ Calif Davis, Dept Neurol, Davis, CA 95616 USA. NINDS, Mol Therapeut Sect, Lab Mol Med & Neurosci, NIH, Bethesda, MD 20892 USA. RP Eberling, JL (reprint author), Lawrence Berkeley Lab, Ctr Funct Imaging, 1 Cyclotron Rd,Mail Stop 55-121, Berkeley, CA 94720 USA. NR 24 TC 18 Z9 19 U1 0 U2 0 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0014-4886 J9 EXP NEUROL JI Exp. Neurol. PD OCT PY 2000 VL 165 IS 2 BP 342 EP 346 DI 10.1006/exnr.2000.7470 PG 5 WC Neurosciences SC Neurosciences & Neurology GA 358FM UT WOS:000089547800013 PM 10993693 ER PT J AU Prestridge, K Rightley, PM Vorobieff, P Benjamin, RF Kurnit, NA AF Prestridge, K Rightley, PM Vorobieff, P Benjamin, RF Kurnit, NA TI Simultaneous density-field visualization and PIV of a shock-accelerated gas curtain SO EXPERIMENTS IN FLUIDS LA English DT Article ID THIN FLUID LAYER; INSTABILITY; TRANSITION; TURBULENCE; EVOLUTION; PATTERNS; GROWTH AB We describe a highly-detailed experimental characterization of the Richtmyer-Meshkov instability (the impulsively driven Rayleigh-Taylor instability) (Meshkov 1969; Richtmyer 1960). In our experiment, a vertical curtain of heavy gas (SF6) flows into the test section of an air-filled, horizontal shock tube. The instability evolves after a Mach 1.2 shock passes through the curtain. For visualization, we pre-mix the SF6 with a small (similar to 10(-5)) volume fraction of sub-micron-sized glycol/water droplets. A horizontal section of the flow is illuminated by a light sheet produced by a combination of a customized, burst-mode Nd:YAG laser and a commercial pulsed laser. Three CCD cameras are employed in visualization. The "dynamic imaging camera" images the entire test section, but does not detect the individual droplets. It produces a sequence of instantaneous images of local droplet concentration, which in the post-shock flow is proportional to density. The gas curtain is convected out of the test section about 1 ms after the shock passes through the curtain. A second camera images the initial conditions with high resolution, since the initial conditions vary from test to test. The third camera, "PIV camera," has a spatial resolution sufficient to detect the individual droplets in the light sheet. Images from this camera are interrogated using Particle Image Velocimetry (PIV) to recover instantaneous snapshots of the velocity field in a small (19 x 14 mm) field of view. The fidelity of the flow-seeding technique for density-field acquisition and the reliability of the PIV technique are both quantified in this paper. In combination with wide-field density data, PIV measurements give us additional physical insight into the evolution of the Richtmyer-Meshkov instability in a problem which serves as an excellent test case for general transition-to-turbulence studies. C1 Univ Calif Los Alamos Natl Lab, Dynam Experimentat Div, Los Alamos, NM 87545 USA. RP Prestridge, K (reprint author), Univ Calif Los Alamos Natl Lab, Dynam Experimentat Div, MS P940, Los Alamos, NM 87545 USA. RI Vorobieff, Peter/B-3376-2011; Prestridge, Kathy/C-1137-2012; OI Prestridge, Kathy/0000-0003-2425-5086; Vorobieff, Peter/0000-0003-0631-7263 NR 17 TC 25 Z9 32 U1 1 U2 7 PU SPRINGER-VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0723-4864 J9 EXP FLUIDS JI Exp. Fluids PD OCT PY 2000 VL 29 IS 4 BP 339 EP 346 DI 10.1007/s003489900091 PG 8 WC Engineering, Mechanical; Mechanics SC Engineering; Mechanics GA 365YV UT WOS:000089978800005 ER PT J AU Mac Gregor, MH AF Mac Gregor, MH TI A unified quantum Hall close-packed composite boson (CPCB) model SO FOUNDATIONS OF PHYSICS LETTERS LA English DT Article ID NOBEL LECTURE; FERMION AB Single-wavelength Landau cyclotron orbitals (SWOs) have been used as quantum Hall basis states to reproduce integer quantum Hall plateaus in a two-dimensional (2D) close-packing representation. But at the high magnetic fields B that correspond to fractional Hall plateaus, these SWOs are too small to give close packing. It is conventionally assumed that the fractional quantum Hall states are formed from collective electron excitations (CEEs). However, by invoking the use of multiple wavelength Landau orbitals (MWOs), we can close-pack the fractional Hall plateaus in the same manner as the integer plateaus. Quantum Hall plateaus are characterized by the filling fractions nu = n(e)/n(phi) = k/m, where k = 1,2,... (all integers) and m = 1,3,... (all odd integers), and where n(e) and n(phi) are the 2D electron e and magnetic flux phi = h/e densities, respectively. A composite particle (CP) is a bound state of an electron and m flux quanta phi. If m is even or odd, the CP is a composite fermion (CF) or composite boson (CB). In the CEE models, both CF and CB formalisms have been used. In the alternative MWO approach introduced here, the close-packed MWOs on a nu = k/m plateau each contain m de Broglie wavelengths lambda. Each MWO traps m phi external flux quanta, produces m phi diamagnetic induced flux quanta, and carries the filling fraction nu, which accounts for the extreme accuracy (one part in 10(8)) of the Hall plateau conductance, sigma (H) = nue(2)/h. Since m is odd, these MWOs are CB states, and they form a boson condensate of close-packed composite boson (CPCB) states. The m = l(m > 1) CPCBs tile the integer (fractional) Hall plateaus. The filling fraction index k corresponds to k layers of CPCB orbitals. Plateau formation itself is due to the linear B dependence of the density of CPCB states. The CPCBs are decoupled from the semiconductor substrate, and hence may have large m* effective mass values THE MWOs near the nu = 1/2 non-plateau region are m = 2 CF states. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Mac Gregor, MH (reprint author), Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 25 TC 1 Z9 1 U1 0 U2 0 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0894-9875 J9 FOUND PHYS LETT JI Found. Phys. Lett. PD OCT PY 2000 VL 13 IS 5 BP 443 EP 460 DI 10.1023/A:1007880715548 PG 18 WC Physics, Multidisciplinary SC Physics GA 376GJ UT WOS:000165449600003 ER PT J AU Scheuring, I Karolyi, G Pentek, A Tel, T Toroczkai, Z AF Scheuring, I Karolyi, G Pentek, A Tel, T Toroczkai, Z TI A model for resolving the plankton paradox: coexistence in open flows SO FRESHWATER BIOLOGY LA English DT Article; Proceedings Paper CT Workshop on Plankton Population Dynamics: Food Web Interactions and Abiotic Constraints CY NOV, 1998 CL CONSTANCE, GERMANY DE chaotic advection; environmental flow; fractal set; hydrodynamical flow; population dynamics ID OPEN HYDRODYNAMICAL FLOWS; CHAOTIC SCATTERING; DISTURBANCE; BOUNDARIES; ADVECTION; DIVERSITY; DYNAMICS; PHYTOPLANKTON; ECOLOGY; SCALES AB 1. Recent developments in the field of chaotic advection in hydrodynamical/environmental flows encourage us to revisit the population dynamics of competing species in open aquatic systems. 2. We assume that these species are in competition for a common limiting resource in. open flows with chaotic advection dynamics. As an illustrative example, we consider a time periodic two-dimensional flow of viscous fluid (water) around a cylindrical obstacle. 3. Individuals accumulate along a fractal set in the wake of the cylinder, which acts as a catalyst for the biological reproduction process. While in homogeneous, well mixed environments only one species could survive this competition, coexistence of competitors is typical in our hydrodynamical system. 4. It is shown that a steady state sets in after sufficiently long times. In this state, the relative density of competitors is determined rather by the fractal nature of the spatial distribution of the advected species, and by their initial conditions, than by their competitive abilities. We argue that two factors, the strong chaotic mixing along a fractal set and the boundary layer around the obstacle, are responsible for the coexistence. C1 Eotvos Lorand Univ, Dept Plant Taxon & Ecol, Res Grp Ecol & Theoret Biol, H-1083 Budapest, Hungary. Tech Univ Budapest, Dept Civil Engn 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. Virginia Polytech Inst & State Univ, Dept Phys, Blacksburg, VA 24061 USA. Los Alamos Natl Lab, Ctr Nonlinear Studies, Los Alamos, NM 87545 USA. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Scheuring, I (reprint author), Eotvos Lorand Univ, Dept Plant Taxon & Ecol, Res Grp Ecol & Theoret Biol, Ludovika Ter 2, H-1083 Budapest, Hungary. EM shieazsf@ludens.elte.hu RI Toroczkai, Zoltan/A-3421-2008; Karolyi, Gyorgy/A-5073-2008; Scheuring, Istvan/A-5368-2011; OI Toroczkai, Zoltan/0000-0002-6602-2849; Scheuring, Istvan/0000-0002-8108-8897; Karolyi, Gyorgy/0000-0002-1021-9554 NR 42 TC 33 Z9 34 U1 2 U2 6 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 0046-5070 J9 FRESHWATER BIOL JI Freshw. Biol. PD OCT PY 2000 VL 45 IS 2 BP 123 EP 132 DI 10.1046/j.1365-2427.2000.00665.x PG 10 WC Marine & Freshwater Biology SC Marine & Freshwater Biology GA 369UZ UT WOS:000165086500003 ER PT J AU Ammerlahn, HR Goldsby, ME Johnson, MM Nicol, DM AF Ammerlahn, HR Goldsby, ME Johnson, MM Nicol, DM TI A geographically distributed enterprise simulation system SO FUTURE GENERATION COMPUTER SYSTEMS-THE INTERNATIONAL JOURNAL OF ESCIENCE LA English DT Article DE enterprise modeling; parallel discrete-event simulation; human-in-the-loop; distributed role-based access control; Java; security; legacy systems AB Sandia National Laboratories has the role of system integrator in the US Department of Energy's Nuclear Weapons Complex (NWC) and the responsibility for maintaining the nuclear stockpile. Maintenance is a complex task that involves a great number of geographically distributed functions, and a variety of analysis tools and models are used to plan operations, assess capabilities and guide political decisions. We are developing a framework for modeling the NWC unde interactive human control. The framework consists of a simulation system whose users and components are distributed across the entire United States. The purpose of the system is to support decisions about questions ranging from low-level operational matters involving only a sub-component of the complex to high-level policy issues requiring simulation of the entire complex. The system integrates multiple domain-specific legacy models and policy models and allows simulation at varying levels of detail. To provide such a framework, we have had to address a number of technical problems, whose solution is the focus of this paper. The three most fundamental problems are to provide geographically distributed, synchronized human participation in the simulation; to provide distributed ownership and security in such a way that the facility hosting a domain-specific model retains all rights to provide or deny a user access to its information; and to integrate legacy models written in a variety of tools or languages and executed on different platforms. Key features of our approach are the use of the Java language and the coordination of the simulation through a new parallel discrete-event simulation system. (C) 2000 Elsevier Science B.V. All rights reserved. C1 Sandia Natl Labs, Syst Studies Dept 8114, Livermore, CA 94551 USA. Dartmouth Coll, Hanover, NH 03755 USA. RP Sandia Natl Labs, Syst Studies Dept 8114, MS 9201,POB 969, Livermore, CA 94551 USA. EM megolds@ca.sandia.gov NR 9 TC 3 Z9 3 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-739X EI 1872-7115 J9 FUTURE GENER COMP SY JI Futur. Gener. Comp. Syst. PD OCT PY 2000 VL 17 IS 2 SI SI BP 135 EP 146 DI 10.1016/S0167-739X(99)00109-0 PG 12 WC Computer Science, Theory & Methods SC Computer Science GA 365DN UT WOS:000089933300005 ER PT J AU Johnson, TM Roback, RC McLing, TL Bullen, TD DePaolo, DJ Doughty, C Hunt, RJ Smith, RW Cecil, LD Murrell, MT AF Johnson, TM Roback, RC McLing, TL Bullen, TD DePaolo, DJ Doughty, C Hunt, RJ Smith, RW Cecil, LD Murrell, MT TI Groundwater "fast paths" in the Snake River Plain aquifer: Radiogenic isotope ratios as natural groundwater tracers SO GEOLOGY LA English DT Article DE groundwater tracers; isotope ratios; Snake River Plain; aquifer properties; aqueous solutions ID IDAHO; ORIGIN AB Preferential flow paths are expected in many groundwater systems and must be located because they can greatly affect contaminant transport. The fundamental characteristics of radiogenic isotope ratios in chemically evolving waters make them highly effective as preferential now path indicators. These ratios tend to be more easily interpreted than solute-concentration data because their response to,vater-rock interaction is less complex. We demonstrate this approach with ground,vater Sr-87/Sr-86 ratios in the Snake River Plain aquifer within and near the Idaho National Engineering and Environmental Laboratory. These data reveal slow-flow zones as lower Sr-87/Sr-86 areas created by prolonged interaction with the host basalts and a relatively fast flowing zone as a high Sr-87/Sr-86 area. C1 Univ Illinois, Dept Geol, Urbana, IL 61801 USA. Univ Calif Los Alamos Natl Lab, Environm Sci & Waste Technol Div, Los Alamos, NM 87545 USA. Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. US Geol Survey, Div Water Resources, Menlo Park, CA 94025 USA. Univ Calif Berkeley, Dept Geol & Geophys, Berkeley Ctr Isotope Geochem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Earth Sci, Berkeley, CA 94720 USA. US Geol Survey, Div Water Resources, Middleton, WI 53562 USA. US Geol Survey, Idaho Falls, ID 83402 USA. Univ Calif Los Alamos Natl Lab, Chem Sci & Technol Div, Los Alamos, NM 87545 USA. RP Johnson, TM (reprint author), Univ Illinois, Dept Geol, 245 Nat Hist Bldg,MC-102, Urbana, IL 61801 USA. RI Johnson, Thomas/A-2740-2008; Doughty, Christine/G-2389-2015 OI Johnson, Thomas/0000-0003-1620-1408; NR 23 TC 22 Z9 23 U1 3 U2 5 PU GEOLOGICAL SOC AMERICA, INC PI BOULDER PA PO BOX 9140, BOULDER, CO 80301-9140 USA SN 0091-7613 J9 GEOLOGY JI Geology PD OCT PY 2000 VL 28 IS 10 BP 871 EP 874 DI 10.1130/0091-7613(2000)028<0871:GFPITS>2.3.CO;2 PG 4 WC Geology SC Geology GA 364KV UT WOS:000089892300002 ER PT J AU Hersman, LE Huang, A Maurice, PA Forsythe, JE AF Hersman, LE Huang, A Maurice, PA Forsythe, JE TI Siderophore production and iron reduction by Pseudomonas mendocina in response to iron deprivation SO GEOMICROBIOLOGY JOURNAL LA English DT Article DE bacteria; iron; iron reduction; P. mendocina; siderophore ID SACCHAROMYCES-CEREVISIAE; PROMOTED DISSOLUTION; FERRIC-REDUCTASE; IDENTIFICATION; ASSIMILATION; GOETHITE; ACIDS AB In aerobic environments microorganisms are faced with a discrepancy of similar to 10 orders of magnitude between the available Fe (similar to 10(-17) M) and their metabolic requirement for it (similar to 10(-7) M). In contrast to facultative anaerobic environments, where dissimilatory iron-reducing bacteria (DIRB) are often abundant, few studies have detailed microbial interactions with Fe(III) (hydr) oxides in aerobic environments. To better understand acquisition of Fe from Fe(III) (hydr)oxides, we investigated the production of siderophore and Fe(III) reduction by a strict aerobe in the presence of synthetic hematite as a source of Fe. Pseudomonas mendocina grew best when Fe was supplied as FeEDTA (similar to1.8 x 10(8) colony-forming units [CFU] ml(-1)), grew abundantly when Fe was supplied as hematite (similar to1.2 x 10(8) CFU ml(-1)), and grew poorly when Fe was withheld from the medium (similar to5.5 x 10(7) CFU ml(-1)). As expected, negligible siderophore was produced per cell when Fe was supplied as FeEDTA and more siderophore was produced in the hematite flasks than in the controls. Thus, growth of P. mendocina and the production of siderophore in the presence of hematite present compelling evidence that siderophore was produced as a mechanism to acquire Fe from hematite. For the Fe reduction experiments, Fe reduction by components of the supernatant fluid was induced weakly when Fe was supplied as hematite or as FeEDTA, but much more when the cells were cultured under extreme Fe deprivation. In fact, 16 times as much Fe reduction occurred in the controls as in the presence of either of the FeEDTA or hematite amendments. Our results, which contravene the long-held assumptions that Fe acquisition was facilitated solely by siderophores, provides a new perspective regarding microbial interactions with Fe-bearing minerals. C1 Univ Calif Los Alamos Natl Lab, Biosci Div, Los Alamos, NM 87545 USA. Univ Notre Dame, Dept Civil Engn & Geol Sci, Notre Dame, IN USA. RP Hersman, LE (reprint author), Univ Calif Los Alamos Natl Lab, Biosci Div, MS-M888, Los Alamos, NM 87545 USA. NR 26 TC 30 Z9 30 U1 2 U2 9 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USA SN 0149-0451 J9 GEOMICROBIOL J JI Geomicrobiol. J. PD OCT-DEC PY 2000 VL 17 IS 4 BP 261 EP 273 DI 10.1080/01490450050192965 PG 13 WC Environmental Sciences; Geosciences, Multidisciplinary SC Environmental Sciences & Ecology; Geology GA 388MM UT WOS:000166184900001 ER PT J AU Fujita, Y Ferris, EG Lawson, RD Colwell, FS Smith, RW AF Fujita, Y Ferris, EG Lawson, RD Colwell, FS Smith, RW TI Calcium carbonate precipitation by ureolytic subsurface bacteria SO GEOMICROBIOLOGY JOURNAL LA English DT Article DE calcite; carbonate; microorganism; remediation; subsurface; urease ID MICROBIAL PRECIPITATION; COMMUNITIES; COLLECTION; SEDIMENTS; AQUIFER AB Coprecipitation in carbonate minerals offers a means of slowing the transport of divalent radionuclides and contaminant metals (e.g., Sr-90(2+), UO22+, Co2+) in the subsurface. It may be possible to accelerate this process by stimulating the native microbial community to generate chemical conditions favoring carbonate precipitation. In a preliminary evaluation of this approach, we investigated the ability of ureolytic subsurface bacteria to produce alkaline conditions conducive to calcium carbonate precipitation. Groundwater samples from the Eastern Snake River Plain (ESRP) aquifer in Idaho were screened for urea-hydrolyzing microorganisms; three isolates were selected for further evaluation. Analysis of 16S rRNA gene sequences indicated that two of the ESRP isolates were of the genus Pseudomonas, and the other was a Variovorax sp. The specific urease activities of the ESRP isolates appeared to be similar to each other but less than that of Bacillus pasteurii, a known urease-positive organism. However, calcium carbonate was rapidly precipitated in all cultures that were supplied with urea and calcium, and X-ray diffraction analyses indicated that calcite was always the predominant carbonate polymorph produced. The correspondence between measured calcium concentrations and equilibrium predictions suggested that the rate of calcite precipitation was directly linked to the rate of urea hydrolysis. These results are promising with respect to the potential utility of this approach for in situ remediation and indicate that further evaluation of this approach under conditions more closely simulating environmental conditions is warranted. C1 Idaho Natl Engn & Environm Labs, Dept Biotechnol, Idaho Falls, ID 83415 USA. Univ Toronto, Dept Geol, Toronto, ON, Canada. Idaho State Univ, Dept Biol Sci, Pocatello, ID 83209 USA. RP Fujita, Y (reprint author), Idaho Natl Engn & Environm Labs, Dept Biotechnol, POB 1625, Idaho Falls, ID 83415 USA. NR 26 TC 120 Z9 135 U1 5 U2 33 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USA SN 0149-0451 J9 GEOMICROBIOL J JI Geomicrobiol. J. PD OCT-DEC PY 2000 VL 17 IS 4 BP 305 EP 318 DI 10.1080/782198884 PG 14 WC Environmental Sciences; Geosciences, Multidisciplinary SC Environmental Sciences & Ecology; Geology GA 388MM UT WOS:000166184900004 ER PT J AU Wildenschild, D Roberts, JJ Carlberg, ED AF Wildenschild, D Roberts, JJ Carlberg, ED TI On the relationship between microstructure and electrical and hydraulic properties of sand-clay mixtures SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID POROUS-MEDIA; SHALY SANDS; PERMEABILITY; CONDUCTIVITY; TRANSPORT AB A series of laboratory experiments, including measurements of electrical properties, permeability, and porosity, were performed on saturated sand-clay mixtures. Different mixtures and packing geometries of quartz sand and 0 to 10% Na-montmorillonite clay were investigated using solutions of CaCl2 and deionized water. Two main regions of electrical conduction exist: a region dominated by surface conduction and a region where the ionic strength of the saturating fluid controlled conduction. For low fluid conductivities, the sample geometry was found to greatly affect the magnitude of the surface conductance. The influence of the microstructural properties on the electrical properties was quantified by estimating formation factors, Lambda-parameters, and surface conductances. The surface conductances estimated using the theory of Johnson ct al. [1986] agreed well with measured values. We suggest that high and low bounds on the expected surface and bulk conductances in a natural system can be derived from the measurements on these artificial geometries. C1 Univ Calif Lawrence Livermore Natl Lab, Expt Geophys Grp, Livermore, CA 94551 USA. RP Wildenschild, D (reprint author), Univ Calif Lawrence Livermore Natl Lab, Expt Geophys Grp, 7000 E Ave,L-201, Livermore, CA 94551 USA. OI Wildenschild, Dorthe/0000-0002-6504-7817 NR 9 TC 31 Z9 31 U1 0 U2 8 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD OCT 1 PY 2000 VL 27 IS 19 BP 3085 EP 3088 DI 10.1029/2000GL011553 PG 4 WC Geosciences, Multidisciplinary SC Geology GA 361FG UT WOS:000089711900015 ER PT J AU Charter, NW Mahal, LK Koshland, DE Bertozzi, CR AF Charter, NW Mahal, LK Koshland, DE Bertozzi, CR TI Biosynthetic incorporation of unnatural sialic acids into polysialic acid on neural cells SO GLYCOBIOLOGY LA English DT Article DE polysialyltransferase; NCAM; sialic acid; biosynthesis ID DEVELOPMENTALLY-REGULATED MEMBER; EMBRYONAL CARCINOMA-CELLS; ADHESION MOLECULE; OLFACTORY-BULB; LONG-TERM; POLYSIALYLATION; PLASTICITY; EXPRESSION; NEURONS; STX AB In this study we demonstrate that polysialyltransferases are capable of accepting unnatural substrates in terminally differentiated human neurons. Polysialyltransferases catalyze the glycosylation of the neural cell adhesion molecule (NCAM) with polysialic acid (PSA). The unnatural sialic acid analog, N-levulinoyl sialic acid (SiaLev), was incorporated into cell surface glycoconjugates including PSA by the incubation of cultured neurons with the metabolic precursor N-levulinoylmannosamine (ManLev), The ketone group within the levulinoyl side chain of SiaLev was then used as a chemical handle for detection using a biotin probe. The incorporation of SiaLev residues into PSA was demonstrated by protection from sialidases that can cleave natural sialic acids but not those bearing unnatural N-acyl groups. The presence of SiaLev groups on the neuronal cell surface did not impede neurite outgrowth or significantly affect the distribution of PSA on neuronal compartments, Since PSA is important in neural plasticity and development, this mechanism for modulating PSA structure might be useful for functional studies. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Mol & Cell Biol, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Adv Mat, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Bertozzi, CR (reprint author), Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. FU NIDDK NIH HHS [DK09765]; NIGMS NIH HHS [GM58867-01] NR 47 TC 25 Z9 25 U1 0 U2 3 PU OXFORD UNIV PRESS INC PI CARY PA JOURNALS DEPT, 2001 EVANS RD, CARY, NC 27513 USA SN 0959-6658 J9 GLYCOBIOLOGY JI Glycobiology PD OCT PY 2000 VL 10 IS 10 BP 1049 EP 1056 DI 10.1093/glycob/10.10.1049 PG 8 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 360JN UT WOS:000089664300011 PM 11030751 ER PT J AU Ruhm, W Knie, K Rugel, G Marchetti, AA Faestermann, T Wallner, C McAninch, JE Straume, T Korschinek, G AF Ruhm, W Knie, K Rugel, G Marchetti, AA Faestermann, T Wallner, C McAninch, JE Straume, T Korschinek, G TI Accelerator mass spectrometry of Ni-63 at the Munich Tandem Laboratory for estimating fast neutron fluences from the Hiroshima atomic bomb SO HEALTH PHYSICS LA English DT Article DE neutrons; Hiroshima; accelerators; atomic bomb ID DOSIMETRY SYSTEM 1986; EU-152; CO-60; SEPARATION; CL-36; CA-41; IONS; DS86; RISK; AMS AB After the release of the present dosimetry system DS86 in 1987, measurements have shown that DS86 may substantially underestimate thermal neutron fluences at large distances (>1,000 m) from the hypocenter in Hiroshima. This discrepancy casts doubts on the DS86 neutron source term and, consequently, the survivors' estimated neutron doses. However, the doses were caused mainly by fast neutrons. To determine retrospectively fast neutron fluences in Hiroshima, the reaction Cu-63(n, p)Ni-63 can be used, if adequate copper samples can be found. Measuring Ni-63 (half life 100 y) in Hiroshima samples requires a very sensitive technique, such as accelerator mass spectrometry (AMS), because of the relatively small amounts of Ni-63 expected (similar to 10(5)-10(6) atoms per gram of copper). Experiments performed at Lawrence Livermore National Laboratory have demonstrated in 1996 that AMS can be used to measure Ni-63 in Hiroshima copper samples. Subsequently, a collaboration was established with the Technical University of Munich in view of its potential to perform more sensitive measurements of Ni-63 than the Livermore facility and in the interest of interlaboratory validation. This paper presents the progress made at the Munich facility in the measurement of Ni-63 by AMS. The Munich accelerator mass spectrometry facility is a combination of a high energy tandem accelerator and a detection system featuring a gas-filled magnet. It is designed for high sensitivity measurements of long-lived radioisotopes. Optimization of the ion source setup has further improved the sensitivity for Ni-63 by reducing the background level of the Cu-63 isobar interference by about two orders of magnitude. Current background levels correspond to a ratio of Ni-63/Ni<2x10(-14) and suggest that, with adequate copper samples, the assessment of fast neutron fluences in Hiroshima and Nagasaki is possible for ground distances of up to 1500 m, and-under favorable conditions-even beyond. To demonstrate this capability, we have measured successfully Ni-63/Ni ratios as low as (3.5 +/- 0.6) x 10(-13). The latter are, based on DS86, representative of a ratio expected from a typical Hiroshima copper sample at about 1,300-m ground range. C1 Univ Munich, Inst Radiobiol, D-80336 Munich, Germany. Tech Univ Munich, Fac Phys, D-85747 Garching, Germany. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Utah, Salt Lake City, UT 84108 USA. EM w.ruehm@lrz.uni-muenchen.de NR 33 TC 18 Z9 19 U1 0 U2 2 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0017-9078 EI 1538-5159 J9 HEALTH PHYS JI Health Phys. PD OCT PY 2000 VL 79 IS 4 BP 358 EP 364 PG 7 WC Environmental Sciences; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 355NN UT WOS:000089391900002 PM 11007457 ER PT J AU Kocher, DC Trabalka, JR AF Kocher, DC Trabalka, JR TI On the application of a radiation weighting factor for alpha particles in protection of non-human biota SO HEALTH PHYSICS LA English DT Article DE alpha particles; relative biological effectiveness; radiation protection; safety standards AB Radiation protection standards for non-human biota have been expressed in terms of absorbed dose. In calculating dose to biota, some investigators have modified the absorbed dose due to alpha particles by a factor of 20, based on the radiation weighting factor used in protection of humans, to account for the greater effectiveness of these radiations in producing biological damage, However, this value is intended to apply to stochastic health effects, primarily cancers, whereas deterministic effects have been the primary concern in protection of biota. Based on an analysis by the International Commission on Radiological Protection, the deterministic radiation weighting factor for alpha particles appears to lie in the range of about 5-10. Given the potential importance of this weighting factor in determining allowable levels of alpha-emitting radionuclides in the environment, regulatory authorities must be impressed with the need to develop an appropriate value for use in protection of biota. There also is a need to express doses and dose limits for biota in terms of a quantity other than absorbed dose and to develop an appropriate name for the biologically significant dose to biota. C1 Oak Ridge Natl Lab, Div Life Sci, Oak Ridge, TN 37830 USA. Oak Ridge Natl Lab, Div Chem Technol, Oak Ridge, TN 37831 USA. EM dck@ornl.gov NR 30 TC 23 Z9 25 U1 0 U2 1 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0017-9078 EI 1538-5159 J9 HEALTH PHYS JI Health Phys. PD OCT PY 2000 VL 79 IS 4 BP 407 EP 411 DI 10.1097/00004032-200010000-00009 PG 5 WC Environmental Sciences; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA 355NN UT WOS:000089391900008 PM 11007463 ER PT J AU Alagramam, KN Zahorsky-Reeves, J Wright, CG Pawlowski, KS Erway, LC Stubbs, L Woychik, RP AF Alagramam, KN Zahorsky-Reeves, J Wright, CG Pawlowski, KS Erway, LC Stubbs, L Woychik, RP TI Neuroepithelial defects of the inner ear in a new allele of the mouse mutation Ames waltzer SO HEARING RESEARCH LA English DT Article DE inner ear; mouse mutant; Ames waltzer ID HEREDITARY HEARING-LOSS; COCHLEAR HAIR-CELLS; INSERTIONAL MUTATION; MICE; DEAFNESS; GENES; MOUSE-CHROMOSOME-10; STRAINS AB This report presents new findings regarding a recessive insertional mutation in the transgenic line TgN2742Rpw that causes deafness and circling behavior in mice homozygous for the mutation. The mutant locus was mapped to a region on mouse chromosome 10 close to three spontaneous recessive mutations causing deafness: Ames waltzer (av), Waltzer (v), and Jackson circler (jc) Complementation testing revealed that the TgN2742Rpw mutation is allelic with av. Histological and auditory brainstem response (ABR) evaluation of animals that have the new allele balanced with the av(J) allele (called compound heterozygotes, TgN2742Rpw/av(J)) supports our genetic analysis. ABR evaluation shows complete absence of auditory response throughout the life span of TgN2742Rpw/av(J) compound heterozygotes. Scanning electron microscopy revealed abnormalities of inner and outer hair cell stereocilia in the cochleae of TgN2742Rpw mutants at 10 days after bi;th (DAB). The organ of Corti subsequently undergoes degeneration, leading to nearly complete loss of the cochlear neuroepithelium in older mutants by about 50 DAB. The vestibular neuroepithelia remain morphologically normal until at least 30 DAB. However, by 50 days, degenerative changes are evident in the saccular macula, which progresses to total loss of the saccular neuroepithelium in older animals. The new allele of av reported here will be designated av(TgN2742Rpw). (C) 2000 Elsevier Science B.V. All rights reserved. C1 Case Western Reserve Univ, Rainbow Babies & Childrens Hosp, Dept Pediat, Cleveland, OH 44106 USA. Univ Tennessee, Dept Pathol, Knoxville, TN 37996 USA. Univ Texas, SW Med Ctr, Dept Otorhinolaryngol, Dallas, TX 75235 USA. Univ Cincinnati, Dept Biol Sci, Cincinnati, OH 45221 USA. Univ Calif Lawrence Livermore Natl Lab, Ctr Human Genome, Livermore, CA 94550 USA. RP Woychik, RP (reprint author), Pfizer Global Res & Dev, Alameda Labs, 1501 Harbor Bay Pkwy, Alameda, CA 94502 USA. OI Stubbs, Lisa/0000-0002-9556-1972 FU NIDCD NIH HHS [1RO1-DC03420] NR 28 TC 35 Z9 35 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0378-5955 J9 HEARING RES JI Hear. Res. PD OCT PY 2000 VL 148 IS 1-2 BP 181 EP 191 DI 10.1016/S0378-5955(00)00152-0 PG 11 WC Audiology & Speech-Language Pathology; Neurosciences; Otorhinolaryngology SC Audiology & Speech-Language Pathology; Neurosciences & Neurology; Otorhinolaryngology GA 354DX UT WOS:000089315500016 PM 10978835 ER EF