FN Thomson Reuters Web of Science™ VR 1.0 PT J AU Butts, DA Feller, MB Shatz, CJ Rokhsar, DS AF Butts, DA Feller, MB Shatz, CJ Rokhsar, DS TI Retinal waves are governed by collective network properties SO JOURNAL OF NEUROSCIENCE LA English DT Article DE visual system; development; calcium waves; model; developing retina; correlated activity ID DEVELOPING MAMMALIAN RETINA; STARBURST AMACRINE CELLS; GANGLION-CELLS; NEONATAL HIPPOCAMPUS; DEVELOPING NEOCORTEX; NEURONAL-ACTIVITY; SPINDLE WAVES; CHICK RETINA; OSCILLATIONS; MODEL AB Propagating neural activity in the developing mammalian retina is required for the normal patterning of retinothalamic connections. This activity exhibits a complex spatiotemporal pattern of initiation, propagation, and termination. Here, we discuss the behavior of a model of the developing retina using a combination of simulation and analytic calculation. Our model produces spatially and temporally restricted waves without requiring inhibition, consistent with the early depolarizing action of neurotransmitters in the retina. We find that highly correlated, temporally regular, and spatially restricted activity occurs over a range of network parameters; this ensures that such spatiotemporal patterns can be produced robustly by immature neural networks in which synaptic transmission by individual neurons may be unreliable. Wider variation of these parameters, however, results in several different regimes of wave behavior. We also present evidence that wave properties are locally determined by a single variable, the fraction of recruitable (i.e., nonrefractory) cells within the dendritic field of a retinal neuron. From this perspective, a given local area's ability to support waves with a wide range of propagation velocities-as observed in experiment-reflects the variability in the local state of excitability of that area. This prediction is supported by whole-cell voltage-clamp recordings, which measure significant wave-to-wave variability in the amount of synaptic input a cell receives when it participates in a wave. This approach to describing the developing retina provides unique insight into how the organization of a neural circuit can lead to the generation of complex correlated activity patterns. C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Phys Biosci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Howard Hughes Med Inst, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Mol & Cell Biol, Berkeley, CA 94720 USA. NINDS, NIH, Bethesda, MD 20892 USA. RP Butts, DA (reprint author), Univ Calif Berkeley, Dept Phys, 366 LeConte Hall, Berkeley, CA 94720 USA. RI Butts, Daniel/B-8346-2008 OI Butts, Daniel/0000-0002-0158-5317 FU NIMH NIH HHS [MH 48108] NR 42 TC 56 Z9 56 U1 0 U2 1 PU SOC NEUROSCIENCE PI WASHINGTON PA 11 DUPONT CIRCLE, NW, STE 500, WASHINGTON, DC 20036 USA SN 0270-6474 J9 J NEUROSCI JI J. Neurosci. PD MAY 1 PY 1999 VL 19 IS 9 BP 3580 EP 3593 PG 14 WC Neurosciences SC Neurosciences & Neurology GA 189BF UT WOS:000079883700031 PM 10212317 ER PT J AU Singhal, A Beaucage, G Harris, MT Toth, LM Keefer, KD Lin, JS Hu, MZC Peterson, JR AF Singhal, A Beaucage, G Harris, MT Toth, LM Keefer, KD Lin, JS Hu, MZC Peterson, JR TI Structure and growth kinetics of zirconium hydrous polymers in organic solutions SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article ID SMALL-ANGLE SCATTERING; TITANIUM ALKOXIDES; HYDROLYSIS; SAXS AB The objective of this study was to understand the kinetics of hydrolysis and condensation reactions and structures of zirconium hydrous polymers formed by these reactions. Small angle X-ray scattering (SAXS) measurements were made on solutions for an aging period ranging from 109 ms to few days. Results prove that condensation reactions start before completion of hydrolysis and as a result polymers formed at the earlier stages (t approximate to 100 ms) are weakly crosslinked (linear), On further aging, due to the internal condensation process these weakly cross-linked polymers convert to highly branched polymers with a structure identical to an ideal Gaussian randomly branched polymer with a persistent length (building block) of 8.3 +/- 0.5 Angstrom. (C) 1999 Published by Elsevier Science B.V. All rights reserved. C1 Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Chem Technol, Oak Ridge, TN 37831 USA. Univ Cincinnati, Dept Mat Sci & Engn, Cincinnati, OH 45220 USA. Pacific NW Lab, Richland, WA 99352 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Singhal, A (reprint author), Nanopowder Enterprises Inc, 120 Centennial Ave, Piscataway, NJ 08854 USA. EM amitsin@aol.com OI Hu, Michael/0000-0001-8461-9684 NR 32 TC 9 Z9 10 U1 0 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3093 J9 J NON-CRYST SOLIDS JI J. Non-Cryst. Solids PD MAY 1 PY 1999 VL 246 IS 3 BP 197 EP 208 DI 10.1016/S0022-3093(99)00071-X PG 12 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA 192EF UT WOS:000080064900005 ER PT J AU Morishita, K de la Rubia, TD AF Morishita, K de la Rubia, TD TI A molecular dynamics simulation study of displacement cascades in vanadium SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur ID COMPUTER-SIMULATION; DEFECT PRODUCTION; RADIATION-DAMAGE; RECOIL ENERGY; FCC METALS; IRRADIATION; SOLIDS; COPPER AB Molecular dynamics calculations were performed to simulate the primary state of radiation damage processes in vanadium. The interaction of atoms was described by the embedded atom method (EAM) potential that was modified at close atomic separation to merge smoothly with the universal ZBL-potential for description of the higher energy recoils in cascades. The initial development of displacement cascades was observed to consist of replacement collision sequences (RCSs) and subsequent molten structures at the centers of cascades. We evaluated the efficiencies of defect production in the displacement events initiated from recoils with kinetic energies of up to 20 keV. The Frenkel pair production is found to have a power-law dependence on the primary recoil energies. The energy dependence is obviously different between single and multiple Frenkel pair production. The efficiencies of defect production and cascade mixing are somewhat higher and lower in bcc vanadium cascades, respectively, than those of fee metals. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Morishita, K (reprint author), Kyushu Univ, Appl Mech Res Inst, 6-1 Kasuga Koen, Kasuga, Fukuoka 816, Japan. EM mori@riam.kyushu-u.ac.jp RI U-ID, Kyushu/C-5291-2016; Kyushu, RIAM/F-4018-2015 NR 30 TC 12 Z9 12 U1 1 U2 9 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD MAY PY 1999 VL 271 BP 35 EP 40 DI 10.1016/S0022-3115(98)00643-6 PG 6 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 204RG UT WOS:000080777500009 ER PT J AU Heinisch, HL Singh, BN AF Heinisch, HL Singh, BN TI Simulation of the kinetics of defect accumulation in copper under neutron irradiation SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur ID STOCHASTIC ANNEALING SIMULATION; CASCADES; MICROSTRUCTURE; ENERGY AB Stochastic annealing simulations were originally developed for and successfully used to describe the short-term annealing stage of defect evolution within individual displacement cascades. Applied to a sufficiently large volume with periodic boundaries. stochastic annealing simulations can also provide a description of the evolution of defects produced during continuous irradiation. The irradiation is simulated by successive introduction of collections of defects representing the primary damage state of individual cascades placed in the simulation volume randomly in time and space. Cascade energies and the rate of their occurrence are chosen to approximate the damage due to the neutron flux of the 14 MeV neutron source Rotating Target Neutron Source-II (RTNS-II). The cascades are chosen from a library of cascades generated in molecular dynamics (MD simulations for recoil energies from 5 to 25 keV. The numbers of each type of defect, defect cluster size distributions. as well as the positions of the defects within the crystal, are monitored as a function of time. Simulated defect cluster densities as a function of dose up to 0.1 dpa at room temperature are compared to experimental results. The simulated cluster densities are within about a factor of two of the experimental results over several orders of magnitude of dose. The effects on damage accumulation due to dose, dose rate, cascade overlap and interstitial cluster mobilities are demonstrated with examples. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Riso Natl Lab, Dept Mat, DK-4000 Roskilde, Denmark. Pacific NW Natl Lab, Richland, WA 99352 USA. RP Heinisch, HL (reprint author), Pacific NW Natl Lab, POB 999,MS P8-15, Richland, WA 99352 USA. EM hl_heinisch@pnl.gov NR 11 TC 11 Z9 11 U1 1 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD MAY PY 1999 VL 271 BP 46 EP 51 DI 10.1016/S0022-3115(98)00729-6 PG 6 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 204RG UT WOS:000080777500011 ER PT J AU Stoller, RE Greenwood, LR AF Stoller, RE Greenwood, LR TI Subcascade formation in displacement cascade simulations: Implications for fusion reactor materials SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur ID PRIMARY DAMAGE FORMATION; MOLECULAR-DYNAMICS; IRON; RATES AB Displacement cascade formation in iron has been investigated by the method of molecular dynamics (MD) for cascade energies up to 40 keV, corresponding to PKA energies up to 61 keV. The results of these simulations have been used in the SPECOMP code to obtain effective, energy-dependent cross sections for two measures of primary damage production: (1) the number of surviving point defects expressed as a fraction of the those predicted by the standard secondary displacement model by Norgett, Robinson, and Torrens (NRT), and (2) the fraction of the surviving interstitials contained in clusters that formed during the cascade event. The primary knockon atom spectra for iron obtained from the SPECTER code have been used to weight these MD-based damage production cross sections in order to obtain spectrally averaged values for several locations in commercial fission reactors, materials test reactors, and a DT fusion reactor (ITER) first wall. An evaluation of these results indicates that neutron energy spectrum differences between the various environments do not lead to significant differences between the average primary damage formation parameters. This conclusion implies that the displacement damage component of radiation damage produced in a DT fusion reactor should be well simulated by irradiation in a fission reactor neutron spectrum, and that differences in nuclear transmutation production may be the primary source of uncertainty in the prediction of material performance at high doses in DT fusion reactors. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. Pacific NW Natl Lab, Environm Technol Div, Richland, WA 99352 USA. RP Stoller, RE (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, POB 2008, Oak Ridge, TN 37831 USA. EM rkn@ornl.gov RI Stoller, Roger/H-4454-2011; Greenwood, Lawrence/H-9539-2016 OI Greenwood, Lawrence/0000-0001-6563-0650 NR 14 TC 48 Z9 49 U1 0 U2 24 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD MAY PY 1999 VL 271 BP 57 EP 62 DI 10.1016/S0022-3115(98)00730-2 PG 6 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 204RG UT WOS:000080777500013 ER PT J AU Woo, CH Garner, FA AF Woo, CH Garner, FA TI Contribution to irradiation creep arising from gas-driven bubble growth SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur ID CASCADE AB Although the majority of the irradiation creep data have been developed in fast reactors where the helium generation rates are rather low, many applications of such data involve neutron or charged particle spectra where the helium generation rates are much larger. It also appears that hydrogen can accumulate in austenitic steels when large amounts of cogenerated helium are also present. In such spectra it has been recently predicted that large gas generation rates can lead to an acceleration of the irradiation creep rate under some conditions often found or expected in some fusion designs, near-core components of light water reactors, and in some accelerator-driven spallation devices. In the present paper, this possibility is theoretically explored and shown to be feasible. As a result, an additional degree of conservatism should be included when fast reactor data are applied to spectral environments where large gas generation rates are expected. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Hong Kong Polytech Univ, Dept Mech Engn, Hong Kong, Peoples R China. Pacific NW Lab, Richland, WA 99352 USA. RP Woo, CH (reprint author), Hong Kong Polytech Univ, Dept Mech Engn, Hong Kong, Peoples R China. EM mmchwoo@polyu.edu.hk RI Woo, Chung Ho/E-3657-2010 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 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD MAY PY 1999 VL 271 BP 78 EP 83 DI 10.1016/S0022-3115(98)00731-4 PG 6 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 204RG UT WOS:000080777500017 ER PT J AU Kohno, Y Kohyama, A Hirose, T Hamilton, ML Narui, M AF Kohno, Y Kohyama, A Hirose, T Hamilton, ML Narui, M TI Mechanical property changes of low activation ferritic martensitic steels after neutron irradiation SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur AB Mechanical property changes of Fe-XCr-2W-0.2V,Ta (X: 2.25-12) low activation ferritic/martensitic steels including Japanese Low Activation Ferritic/martensitic (JLF) steels and F82H after neutron irradiation were investigated with emphasis on Charpy impact property, tensile property and irradiation creep properties. Dose dependence of ductile-to-brittle transition temperature (DBTT) in JLF-1 (9Cr steel) irradiated at 646-700 K increased with irradiation up to 20 dpa and then decreased with further irradiation showing highest DBTT of 260 K at 20 dpa. F82H showed similar dose dependence in DBTT to JLF-1 with higher transition temperature than that of JLF-1 at the same displacement damage. Yield strength in JLF steels and F82H showed similar dose dependence to that of DBTT. Yield. strength increased with irradiation up to 15-20 dpa and then decreased to saturate above about 40 dpa, Irradiation hardening in 7-9%Cr steels (JLF-1, JLF-3, F82H) were observed to be smaller than those in steels with 2.25%Cr (JLF-4) or 12%Cr (JLF-5). Dependences of creep strain on applied hoop stress and neutron fluence were measured to be 1.5 and 1, respectively. Temperature dependence of creep coefficient showed a maximum at about 700 K which was caused by irradiation induced void formation or irradiation enhanced creep deformation. Creep coefficient of F82H was larger than those of JLF steels above 750 K. This was considered to be caused by the differences in N and Ta concentration between F82H and JLF steels, (C) 1999 Elsevier Science B.V. All rights reserved. C1 Univ Tokyo, Dept Mat Sci, Bunkyo Ku, Tokyo 113, Japan. Kyoto Univ, Inst Adv Energy, Kyoto 611, Japan. Pacific NW Lab, Div Sci Mat, Richland, WA 99352 USA. Tohoku Univ, Inst Mat Res, Oarai Branch, Oarai, Ibaraki 31113, Japan. RP Univ Tokyo, Dept Mat Sci, Bunkyo Ku, 7-3-1 Hongo, Tokyo 113, Japan. EM kohno@steel.mm.t.u-tokyo.ac.jp NR 17 TC 35 Z9 41 U1 4 U2 13 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 EI 1873-4820 J9 J NUCL MATER JI J. Nucl. Mater. PD MAY PY 1999 VL 271 BP 145 EP 150 DI 10.1016/S0022-3115(98)00735-1 PG 6 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 204RG UT WOS:000080777500031 ER PT J AU Iwase, A Rehn, LE Baldo, PM Funk, L AF Iwase, A Rehn, LE Baldo, PM Funk, L TI Effects of He implantation on radiation induced segregation in Cu-Au and Ni-Si alloys SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur ID FREELY MIGRATING DEFECTS; CASCADE REMNANTS; ANNIHILATION; IONS AB Effects of He implantation on radiation induced segregation (R1S) in Cu-Au and Ni-Si alloys were investigated using in situ Rutherford backscattering spectrometry during simultaneous irradiation with 1.5-MeV He and low-energy (100 or 400-keV) He ions at elevated temperatures. RIS during single He ion irradiation, and the effects of pre-implantation with low-energy He ions, were also studied. RIS near the specimen surface, which was pronounced during 1.5-MeV He single-ion irradiation, was strongly reduced under low-energy He single-ion irradiation, and during simultaneous irradiation with 1.5-MeV He and low-energy He ions. A similar RIS reduction was also observed in the specimens pre-implanted with low-energy He ions. The experimental results indicate that the accumulated He atoms cause the formation of small bubbles, which provide additional recombination sites for freely migrating defects. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Japan Atom Energy Res Inst, Tokai, Ibaraki 31911, Japan. RP Iwase, A (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. EM iwase@popsvr.tokai.jaeri.go.jp NR 11 TC 1 Z9 1 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD MAY PY 1999 VL 271 BP 321 EP 325 DI 10.1016/S0022-3115(98)00746-6 PG 5 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 204RG UT WOS:000080777500065 ER PT J AU Gomes, IC Tsai, HC Smith, DL AF Gomes, IC Tsai, HC Smith, DL TI Neutronics aspects of a DHCE experiment SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur AB The DHCE (dynamic helium charging experiment) irradiation experiment was conceived to simulate fusion-relevant helium production in a fission reactor irradiation. The main objective is to maintain the helium-to-dpa ratio at, roughly, the same level as expected in a fusion environment. The problem in fission reactor irradiation is that helium production is very low, because the fission neutrons, for basically all structural materials relevant for fusion applications, do not have enough energy to trigger the helium producing reactions. A DHCE experiment involves the decay of tritium to He-3 to produce the required helium during irradiation. This paper describes an analysis of the most important aspects of a DHCE experiment and compares different types of fission reactors and their suitability for performing such an experiment. It is concluded that DHCE experiments are feasible in a certain class of mixed-spectrum fission reactors, but a careful and detailed evaluation, for each facility and condition, must be performed to ensure the success of the experiment. (C) 1999 Published by Elsevier Science B.V. All rights reserved. C1 Argonne Natl Lab, Argonne, IL 60439 USA. RP Gomes, IC (reprint author), Argonne Natl Lab, 9700 S Cass Ave,TD-207, Argonne, IL 60439 USA. EM icgomes@anl.gov NR 3 TC 1 Z9 1 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD MAY PY 1999 VL 271 BP 349 EP 355 DI 10.1016/S0022-3115(98)00719-3 PG 7 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 204RG UT WOS:000080777500071 ER PT J AU Lee, EH Hunn, JD Rao, GR Klueh, RL Mansur, LK AF Lee, EH Hunn, JD Rao, GR Klueh, RL Mansur, LK TI Triple ion beam studies of radiation damage in 9Cr-2WVTa ferritic martensitic steel for a high power spallation neutron source SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur ID INDENTATION; HARDNESS; HELIUM; LOAD AB To simulate radiation damage under a future Spallation Neutron Source (SNS) environment, irradiation experiments were conducted on a candidate 9Cr-2WVTa ferritic/martensitic steel using the Triple Ion Facility (TIF) at ORNL. Irradiation was conducted in single, dual and triple ion beam modes using 3.5 MeV Fe++, 360 keV He+, and 180 keV H+ at 80 degrees C, 200 degrees C and 350 degrees C. These irradiations produced various defects comprising black dots, dislocation loops, line dislocations, and gas bubbles, which led to hardening. The largest increase in hardness, over 63%, was observed after 50 dpa for triple beam irradiation conditions, revealing that both He and H are augmenting the hardening. Hardness increased less than 30%, after 30 dpa at 200 degrees C by triple beams, compatible with neutron irradiation data from previous work which showed about a 30% increase in yield strength after 27.2 dpa at 365 degrees C. However, the very large concentrations of gas bubbles in the matrix and on lath and grain boundaries after these simulated SNS irradiations make predictions of fracture behavior from fission reactor irradiations to spallation target conditions inadvisable. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Lee, EH (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, POB 2008, Oak Ridge, TN 37831 USA. EM leeeh@ornl.gov NR 17 TC 13 Z9 17 U1 1 U2 10 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD MAY PY 1999 VL 271 BP 385 EP 390 DI 10.1016/S0022-3115(98)00722-3 PG 6 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 204RG UT WOS:000080777500078 ER PT J AU Alexander, DJ Zinkle, SJ Rowcliffe, AF AF Alexander, DJ Zinkle, SJ Rowcliffe, AF TI Fracture toughness of copper-base alloys for fusion energy applications SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur ID HOT DUCTILITY; EMBRITTLEMENT AB Oxide-dispersion strengthened copper alloys and a precipitation-hardened copper-nickel-beryllium alloy showed a significant reduction in toughness at elevated temperatures (250 degrees C) as compared to room temperature. This decrease in toughness was much larger than would be expected from the relatively modest changes in the tensile properties over the same temperature range. However, a copper-chromium-zirconium alloy strengthened by precipitation showed only a small decrease in toughness at the higher temperatures. The embrittled alloys showed a transition in fracture mode, from transgranular microvoid coalescence at room temperature to intergranular with localized ductility at high temperatures. The Cu-Cr-Zr alloy maintained the ductile microvoid coalescence failure mode at all test temperatures. (C) 1999 Published by Elsevier science B.V. All rights reserved. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Zinkle, SJ (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, POB 2008, Oak Ridge, TN 37831 USA. EM zinklesj@ornl.gov OI Zinkle, Steven/0000-0003-2890-6915 NR 16 TC 25 Z9 26 U1 1 U2 8 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD MAY PY 1999 VL 271 BP 429 EP 434 DI 10.1016/S0022-3115(98)00798-3 PG 6 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 204RG UT WOS:000080777500087 ER PT J AU Jones, RH Heinisch, HL McCarthy, KA AF Jones, RH Heinisch, HL McCarthy, KA TI Low activation materials SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur AB Low or reduced activation materials are currently bring developed and evaluated as structural materials for fusion energy systems. The goal of developing low activation materials is to provide fusion energy systems with a competitive edge over fission energy systems where high level waste issues abound. The primary low activation materials being developed by the international fusion materials community are: (1) ferritic/martensitic steels, (2) vanadium alloys and (3) SiC/SiC composites. These three materials offer a range of temperature and coolant design options and would likely be the optimum choices even without a low activation criteria. However, there are a number of activation, safety acid disposal issues that must be solved to achieve an optimum blanket design. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Pacific NW Lab, Richland, WA 99352 USA. Idaho Natl Engn & Environm Lab, Idaho Falls, ID USA. RP Jones, RH (reprint author), Pacific NW Lab, MS P8-15,POB 999, Richland, WA 99352 USA. NR 5 TC 30 Z9 32 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD MAY PY 1999 VL 271 BP 518 EP 525 DI 10.1016/S0022-3115(98)00864-2 PG 8 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 204RG UT WOS:000080777500105 ER PT J AU Kohyama, A Bloom, EE Ehrlich, K AF Kohyama, A Bloom, EE Ehrlich, K TI Summary of discussion session: Design and materials SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur C1 Kyoto Univ, Inst Adv Energy, Uji, Kyoto 611, Japan. Oak Ridge Natl Lab, Oak Ridge, TN USA. IMF FZK, Karlsruhe, Germany. RP Kohyama, A (reprint author), Kyoto Univ, Inst Adv Energy, Uji, Kyoto 611, Japan. NR 0 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD MAY PY 1999 VL 271 BP 538 EP 539 DI 10.1016/S0022-3115(98)00867-8 PG 2 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 204RG UT WOS:000080777500108 ER PT J AU Shikama, T Yasuda, K Yamamoto, S Kinoshita, C Zinkle, SJ Hodgson, ER AF Shikama, T Yasuda, K Yamamoto, S Kinoshita, C Zinkle, SJ Hodgson, ER TI Irradiation effects in ceramics for fusion reactor applications SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article; Proceedings Paper CT 8th International Conference on Fusion Reactor Materials (ICFRM-8) CY OCT 26-31, 1997 CL SENDAI, JAPAN SP Tohoku Univ, Inst Mat Res, Min Educ Sci & Culture Japan, Int Symp Supporting Program, Atom Energy Soc Japan, Iron & Steel Inst Japan, Japan Inst Met, Japan Soc Appl Phys, Japan Soc Plasma Sci & Nucl Fus Res, Japanese Welding Soc, Japanese High Temp Soc, Amer Nucl Soc, AIME & ASM, Nucl Met Comm, British Nucl Energy Soc, European Nucl Soc, Japan Convent Bur ID INDUCED ELECTRICAL DEGRADATION; IN-SITU MEASUREMENT; MICROSTRUCTURAL EVOLUTION; DEFECT CLUSTERS; INSULATORS; SPECTRUM; CONDUCTIVITY; ALUMINA; GROWTH AB A review is given on the status of R&D of ceramics for fusion reactor applications. Emphasis is placed on the engineering design activity of fusion reactor, the International Thermonuclear Experimental Reactor, Engineering Design Activities (ITER-EDA) as well as related research of electrical, dielectric and mechanical properties, and fundamental aspects of defects. The paper is based mainly on the presentations and discussion, including a keynote lecture and several short presentations by invited panelists, at the discussion session of 'Ceramic Insulators for Fusion Energy Applications' at ICFRM-8, on 30th October 1997 in Sendai, Japan. This report illustrates how the ITER-EDA and other related international activities have functioned not only to coordinate, but also to promote international collaborations and to mobilize the limited research resources effectively. A database which is necessary for reliable design of diagnostic components in ITER is included in the review. (C) 1999 Published by Elsevier Science B.V. All rights reserved. C1 Tohoku Univ, Inst Mat Res, Oarai Branch, Oarai, Ibaraki 3111313, Japan. Kyushu Univ, Dept Appl Quantum Phys & Nucl Engn, Fukuoka 8128581, Japan. ITER JCT, D-85748 Garching, Germany. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Euratom CIEMAT Fus Assoc, Madrid 28040, Spain. RP Shikama, T (reprint author), Tohoku Univ, Inst Mat Res, Oarai Branch, Oarai, Ibaraki 3111313, Japan. RI Shikama, Tatsuo/C-3042-2011; OI Zinkle, Steven/0000-0003-2890-6915 NR 50 TC 38 Z9 38 U1 1 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD MAY PY 1999 VL 271 BP 560 EP 568 DI 10.1016/S0022-3115(98)00872-1 PG 9 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA 204RG UT WOS:000080777500111 ER PT J AU Wang, G Volkow, ND Levy, AV Fowler, JS Franceschi, D Wong, CT Pappas, NR AF Wang, G Volkow, ND Levy, AV Fowler, JS Franceschi, D Wong, CT Pappas, NR TI The effect of non-uniform resolution of three dimensional acquisition mode (3D) in PET scanner on the measurement of dopamine receptor density. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Brookhaven Natl Lab, Dept Med, Upton, NY 11973 USA. Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1999 VL 40 IS 5 SU S MA 145 BP 36P EP 36P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 192XV UT WOS:000080105800146 ER PT J AU Juweid, M Sparks, R Goldenberg, DM AF Juweid, M Sparks, R Goldenberg, DM TI Radiation absorbed dose to hematopoetic stem cells (HSC) following re-infusion at Y-90 blood level of 0.4 UCI ML post high-dose radioimmunotherapy (RAIT) with Y-90-labeled IGG monoclonal antibodies (MABS). SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Garden State Canc Ctr, Belleville, NJ USA. Oak Ridge Natl Lab, Oak Ridge, TN USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1999 VL 40 IS 5 SU S MA 261 BP 65P EP 65P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 192XV UT WOS:000080105800262 ER PT J AU Srivastava, SC Atkins, HL Krishnamurthy, GT Zanzi, I Silberstein, EB AF Srivastava, SC Atkins, HL Krishnamurthy, GT Zanzi, I Silberstein, EB TI Long-term analysis of clinical data from patients treated with Sn-117m DTPA for metastatic bone pain. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Brookhaven Natl Lab, Upton, NY 11973 USA. Vet Adm Med Ctr, Tucson, AZ 85723 USA. N Shore Univ Hosp, Manhasset, NY USA. Univ Cincinnati, Cincinnati, OH USA. NR 0 TC 3 Z9 3 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1999 VL 40 IS 5 SU S MA 264 BP 65P EP 65P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 192XV UT WOS:000080105800265 ER PT J AU Goldstein, CI Wang, W Gindi, GR AF Goldstein, CI Wang, W Gindi, GR TI Limited-memory quasi-Newton iterative reconstruction in emission computed tomography. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Brookhaven Natl Lab, Upton, NY 11973 USA. SUNY Stony Brook, Stony Brook, NY 11794 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1999 VL 40 IS 5 SU S MA 301 BP 74P EP 75P PG 2 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 192XV UT WOS:000080105800302 ER PT J AU Huber, JS Moses, WW Jones, WF Watson, CC AF Huber, JS Moses, WW Jones, WF Watson, CC TI Effects of LU-176 background radiation on singles transmission for LSO-based PET cameras. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Lawrence Berkeley Lab, Berkeley, CA USA. CTI Inc, Knoxville, TN USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1999 VL 40 IS 5 SU S MA 305 BP 76P EP 76P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 192XV UT WOS:000080105800306 ER PT J AU Maltz, JS Polak, E Budinger, TF AF Maltz, JS Polak, E Budinger, TF TI Simultaneous estimation of spatial and kinetic parameters in single rotation dynamic myocardial SPECT. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1999 VL 40 IS 5 SU S MA 311 BP 77P EP 77P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 192XV UT WOS:000080105800312 ER PT J AU Norenberg, JP Garmestani, K Krenning, BJ Konings, IR Atcher, RW de Jong, M Srinivasan, A Kvols, LK Brechbeil, MW AF Norenberg, JP Garmestani, K Krenning, BJ Konings, IR Atcher, RW de Jong, M Srinivasan, A Kvols, LK Brechbeil, MW TI Radiolabellng methods for the preparation of [Bi-213-DITA(0),TYR3]octreotide (Bi-213-DOTATOC) for peptide receptor radionuclide therapy (PRRT). SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Univ New Mexico, Hlth Sci Ctr, Albuquerque, NM 87131 USA. NCI, Chem Sect, Bethesda, MD 20892 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM USA. Erasmus Univ, Rotterdam, Netherlands. Mallinckrodt Inc, St Louis, MO USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1999 VL 40 IS 5 SU S MA 322 BP 80P EP 80P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 192XV UT WOS:000080105800323 ER PT J AU Gao, DW Ido, A Hanrahan, S VanBrocklin, H Budinger, T Dae, M AF Gao, DW Ido, A Hanrahan, S VanBrocklin, H Budinger, T Dae, M TI Comparison of I-125 iodorotenone and Tc-99m Sestamibi in ischemic and infarcted myocardium. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Univ Calif San Francisco, San Francisco, CA 94143 USA. Lawrence Berkeley Lab, Berkeley, CA USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1999 VL 40 IS 5 SU S MA 352 BP 87P EP 88P PG 2 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 192XV UT WOS:000080105800353 ER PT J AU Li, AN Hausleiter, J Knapp, FF Eigler, N Whiting, JS AF Li, AN Hausleiter, J Knapp, FF Eigler, N Whiting, JS TI A biodistribution and elimination study of 188rhenium in pigs. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Cedars Sinai Med Ctr, Los Angeles, CA 90048 USA. Oak Ridge Natl Lab, Oak Ridge, TN USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1999 VL 40 IS 5 SU S MA 356 BP 88P EP 88P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 192XV UT WOS:000080105800357 ER PT J AU Ding, YS Pyatt, B Fowler, JS Volkow, ND Abumrad, N DeRisi, D AF Ding, YS Pyatt, B Fowler, JS Volkow, ND Abumrad, N DeRisi, D TI A potential use of [F-18]RO41-0960, a selective COMT inhibitor, for PET imaging of estrogen metabolism in breast cancer. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Brookhaven Natl Lab, Upton, NY 11973 USA. N Shore Univ Hosp, Manhasset, NY USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1999 VL 40 IS 5 SU S MA 406 BP 100P EP 101P PG 2 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 192XV UT WOS:000080105800407 ER PT J AU Gatley, SJ Gifford, AN Pyatt, BE Liu, Q Makriyannis, A Volkow, ND AF Gatley, SJ Gifford, AN Pyatt, BE Liu, Q Makriyannis, A Volkow, ND TI Occupancy of brain cannabinoid CB1 receptors and biological activity. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Brookhaven Natl Lab, Upton, NY 11973 USA. Univ Connecticut, Storrs, CT USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1999 VL 40 IS 5 SU S MA 438 BP 108P EP 108P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 192XV UT WOS:000080105800439 ER PT J AU Ding, YS Volkow, ND Logan, J Garza, V Pappas, N King, P Fowler, JS AF Ding, YS Volkow, ND Logan, J Garza, V Pappas, N King, P Fowler, JS TI Occupancy of nicotinic acetylcholine receptors by nicotine doses equivalent to those obtained when smoking a cigarette. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Brookhaven Natl Lab, Upton, NY 11973 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1999 VL 40 IS 5 SU S MA 439 BP 109P EP 109P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 192XV UT WOS:000080105800440 ER PT J AU Gatley, SJ Volkow, ND Gifford, AN Fowler, JS AF Gatley, SJ Volkow, ND Gifford, AN Fowler, JS TI Intravenous doses of cocaine and methylphenidate and dopamine transporter occupancy in mice and men. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Brookhaven Natl Lab, Upton, NY 11973 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1999 VL 40 IS 5 SU S MA 440 BP 109P EP 109P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 192XV UT WOS:000080105800441 ER PT J AU Volkow, ND Wang, GJ Fowler, JS Logan, J Franceschi, D Gatley, SJ Ding, YS Wong, CT Hitzemann, RJ Pappas, NR AF Volkow, ND Wang, GJ Fowler, JS Logan, J Franceschi, D Gatley, SJ Ding, YS Wong, CT Hitzemann, RJ Pappas, NR TI Evidence that elevations in brain dopamine mediate the reinforcing effects of psychostimulants in humans. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Brookhaven Natl Lab, Dept Med, Upton, NY 11973 USA. Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. SUNY Stony Brook, Dept Psychiat, Stony Brook, NY 11794 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1999 VL 40 IS 5 SU S MA 442 BP 109P EP 110P PG 2 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 192XV UT WOS:000080105800443 ER PT J AU Volkow, ND Chang, L Wang, GJ Fowler, JS Franceschi, D Gatley, SJ Wong, CT Hitzemann, RJ Pappas, NR AF Volkow, ND Chang, L Wang, GJ Fowler, JS Franceschi, D Gatley, SJ Wong, CT Hitzemann, RJ Pappas, NR TI In vivo evidence that methamphetamine abuse produces long lasting changes in dopamine transporters in human brain. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Brookhaven Natl Lab, Dept Med, Upton, NY 11973 USA. Univ Calif Los Angeles, Dept Psychiat, Torrance, CA USA. Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. SUNY Stony Brook, Dept Psychiat, Stony Brook, NY 11794 USA. NR 0 TC 2 Z9 2 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1999 VL 40 IS 5 SU S MA 443 BP 110P EP 110P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 192XV UT WOS:000080105800444 ER PT J AU Klein, GJ Reutter, BW Huesman, RH AF Klein, GJ Reutter, BW Huesman, RH TI Data-driven respiratory gating in list mode cardiac PET. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Lawrence Berkeley Lab, Berkeley, CA USA. NR 0 TC 2 Z9 2 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1999 VL 40 IS 5 SU S MA 457 BP 113P EP 113P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 192XV UT WOS:000080105800458 ER PT J AU Raylman, RR Majewski, S Wojcik, R Weisenberger, D Kross, B Popov, V Bishop, HA AF Raylman, RR Majewski, S Wojcik, R Weisenberger, D Kross, B Popov, V Bishop, HA TI Positron emission mammography-guided stereotactic breast biopsy. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 W Virginia Univ, Morgantown, WV USA. Jefferson Lab, Newport News, VA USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1999 VL 40 IS 5 SU S MA 468 BP 116P EP 116P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 192XV UT WOS:000080105800469 ER PT J AU Srivastava, SC Kolsky, KL Joshi, V Sweet, MP Meinken, GE Mausner, LF AF Srivastava, SC Kolsky, KL Joshi, V Sweet, MP Meinken, GE Mausner, LF TI Scandium-47: A replacement for Cu-67 as a beta/gamma therapeutic radiolabel. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Brookhaven Natl Lab, Dept Med, Upton, NY 11973 USA. NR 0 TC 2 Z9 2 U1 0 U2 1 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1999 VL 40 IS 5 SU S MA 489 BP 121P EP 121P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 192XV UT WOS:000080105800490 ER PT J AU Srivastava, SC Meinken, GE Atkins, HL Mausner, LF James, JL AF Srivastava, SC Meinken, GE Atkins, HL Mausner, LF James, JL TI New tin-117m formulations for therapy of cancer in bone. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Brookhaven Natl Lab, Upton, NY 11973 USA. Diatide Inc, Londonderry, NH USA. NR 0 TC 2 Z9 2 U1 0 U2 1 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1999 VL 40 IS 5 SU S MA 490 BP 121P EP 121P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 192XV UT WOS:000080105800491 ER PT J AU Park, MH Gifford, AN Gatley, SJ Volkow, ND AF Park, MH Gifford, AN Gatley, SJ Volkow, ND TI Competition between dopamine (DA) released by amphetamine and radioligands for binding to DA receptors in striatum. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Brookhaven Natl Lab, Upton, NY 11973 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1999 VL 40 IS 5 SU S MA 586 BP 145P EP 145P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 192XV UT WOS:000080105800587 ER PT J AU Wang, G Volkow, D Fowler, JS Franceschi, D Logan, J Pappas, NR Wong, CT Netusil, N AF Wang, G Volkow, D Fowler, JS Franceschi, D Logan, J Pappas, NR Wong, CT Netusil, N TI The effects of aerobic exercise (running) on human striatal dopamine release. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Brookhaven Natl Lab, Dept Med, Upton, NY 11973 USA. Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. NR 0 TC 2 Z9 2 U1 1 U2 2 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1999 VL 40 IS 5 SU S MA 588 BP 146P EP 146P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 192XV UT WOS:000080105800589 ER PT J AU Raylman, RR Majewski, S Wojcik, R Popov, V AF Raylman, RR Majewski, S Wojcik, R Popov, V TI A miniature beta particle-sensitive probe for endoscopy. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Jefferson Lab, Newport News, VA USA. W Virginia Univ, Morgantown, WV 26506 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1999 VL 40 IS 5 SU S MA 600 BP 149P EP 149P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 192XV UT WOS:000080105800601 ER PT J AU McPherson, DW Knapp, FF AF McPherson, DW Knapp, FF TI A simple Sep Pak procedure for the rapid purification of IQNP. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Oak Ridge Natl Lab, Oak Ridge, TN USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1999 VL 40 IS 5 SU S MA 608 BP 151P EP 151P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 192XV UT WOS:000080105800609 ER PT J AU Groch, MW Marshall, RC Spies, SM Groch, PJ Barnett, CA Erwin, WD AF Groch, MW Marshall, RC Spies, SM Groch, PJ Barnett, CA Erwin, WD TI Quantification of abnormal regional ventricular function in infarcted myocardium from gated blood pool SPECT images. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Lawrence Berkeley Lab, Berkeley, CA USA. Northwestern Univ, Chicago, IL 60611 USA. Vet Adm Martinez Med Ctr, Martinez, CA USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1999 VL 40 IS 5 SU S MA 712 BP 156P EP 156P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 192XV UT WOS:000080105800629 ER PT J AU Sloof, GW Bax, JJ Visser, FC Eersels, J Knapp, FF AF Sloof, GW Bax, JJ Visser, FC Eersels, J Knapp, FF TI Nuclear techniques are more sensitive for the detection of viable myocardium than dobutamine echocardiography. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Univ Amsterdam, Acad Med Ctr, NL-1105 AZ Amsterdam, Netherlands. Leiden Univ, Med Ctr, Leiden, Netherlands. Free Univ Amsterdam Hosp, Amsterdam, Netherlands. Oak Ridge Natl Lab, Oak Ridge, TN USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1999 VL 40 IS 5 SU S MA 765 BP 168P EP 169P PG 2 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 192XV UT WOS:000080105800682 ER PT J AU Sloof, GW Visser, FC Comans, EF Teerlink, T Knapp, FF AF Sloof, GW Visser, FC Comans, EF Teerlink, T Knapp, FF TI Kinetics of a dimethyl-branched fatty acid analog: DMIPP in experimental myocardial ischemia. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Oak Ridge Natl Lab, Oak Ridge, TN USA. Free Univ Amsterdam Hosp, Amsterdam, Netherlands. Univ Amsterdam, Acad Med Ctr, NL-1105 AZ Amsterdam, Netherlands. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1999 VL 40 IS 5 SU S MA 827 BP 183P EP 184P PG 2 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 192XV UT WOS:000080105800743 ER PT J AU Zamora, PO Ferretti, JA Som, P Choi, J Kuan, P Osaki, S Stern, R Oster, ZH AF Zamora, PO Ferretti, JA Som, P Choi, J Kuan, P Osaki, S Stern, R Oster, ZH TI On-demand labeling of metal stents with Re-188 for use in treating restenosis. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 InnerDyne Inc, Sunnyvale, CA USA. InnerDyne Inc, Salt Lake City, UT USA. SUNY Stony Brook, Stony Brook, NY 11794 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1999 VL 40 IS 5 SU S MA 825 BP 183P EP 183P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 192XV UT WOS:000080105800741 ER PT J AU Sloof, GW Visser, FC Bax, JJ Knapp, FF AF Sloof, GW Visser, FC Bax, JJ Knapp, FF TI Differences of DMIPP uptake in myocardial sublayers during experimental ischemia. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Oak Ridge Natl Lab, Oak Ridge, TN USA. Free Univ Amsterdam Hosp, Amsterdam, Netherlands. Univ Amsterdam, Acad Med Ctr, NL-1105 AZ Amsterdam, Netherlands. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1999 VL 40 IS 5 SU S MA 831 BP 184P EP 185P PG 2 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 192XV UT WOS:000080105800747 ER PT J AU Palmedo, H Guhlke, S Bender, H Sartor, J Schoeneich, G Risse, J Gruenwald, F Knapp, FF Biersack, HJ AF Palmedo, H Guhlke, S Bender, H Sartor, J Schoeneich, G Risse, J Gruenwald, F Knapp, FF Biersack, HJ TI Dose escalation study with Re-188HEDP in prostate cancer patients with osseous metastases. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Univ Bonn, Dept Nucl Med, D-5300 Bonn, Germany. Dept Urol, Bonn, Germany. Oak Ridge Natl Lab, Oak Ridge, TN USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1999 VL 40 IS 5 SU S MA 974 BP 218P EP 218P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 192XV UT WOS:000080105800889 ER PT J AU Bishayee, A Howell, RW Srivastava, SC Bouchet, LG Bolch, WE Rao, DV AF Bishayee, A Howell, RW Srivastava, SC Bouchet, LG Bolch, WE Rao, DV TI Marrow sparing effects of Sn-117m-DTPA for palliation of bone pain. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Univ Med & Dent New Jersey, New Jersey Med Sch, Dept Radiol, Newark, NJ 07103 USA. Brookhaven Natl Lab, Dept Med, Upton, NY 11973 USA. Univ Florida, Dept Nucl & Radiol Engn, Gainesville, FL USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1999 VL 40 IS 5 SU S MA 978 BP 219P EP 219P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 192XV UT WOS:000080105800893 ER PT J AU Liepe, K Kropp, J Knapp, F Hliscs, R Kuehne, A Franke, WG AF Liepe, K Kropp, J Knapp, F Hliscs, R Kuehne, A Franke, WG TI Kinetics and therapeutic effect of rhenium-188 in palliative treatment of metastatic bone pain. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Univ Technol, Dresden, Germany. Oak Ridge Natl Lab, Nucl Med Grp, Oak Ridge, TN USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1999 VL 40 IS 5 SU S MA 975 BP 219P EP 219P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 192XV UT WOS:000080105800890 ER PT J AU Franceschi, D Volkow, ND Wang, GJ Fowler, JS Logan, J Levy, AV Pappas, NR AF Franceschi, D Volkow, ND Wang, GJ Fowler, JS Logan, J Levy, AV Pappas, NR TI Comparison of measurements of dopamine D2 receptor availability from two PET cameras. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Brookhaven Natl Lab, Upton, NY 11973 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1999 VL 40 IS 5 SU S MA 1176 BP 265P EP 266P PG 2 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 192XV UT WOS:000080105801090 ER PT J AU Fowler, JS Wang, GJ Volkow, ND Franceschi, D Logan, J Pappas, N AF Fowler, JS Wang, GJ Volkow, ND Franceschi, D Logan, J Pappas, N TI Effect of a single cigarette on brain MAO B. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Brookhaven Natl Lab, Upton, NY 11973 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1999 VL 40 IS 5 SU S MA 1215 BP 275P EP 275P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 192XV UT WOS:000080105801129 ER PT J AU Volkow, ND Logan, J Wang, GJ Fowler, JS Gur, RC Franceschi, D Gatley, SJ Ding, YS Pappas, NR AF Volkow, ND Logan, J Wang, GJ Fowler, JS Gur, RC Franceschi, D Gatley, SJ Ding, YS Pappas, NR TI Age-related decreases in dopamine D2 receptors are associated with reductions in frontal metabolism. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Univ Penn, Sch Med, Upton, NY USA. Brookhaven Natl Lab, Upton, NY 11973 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1999 VL 40 IS 5 SU S MA 1218 BP 275P EP 276P PG 2 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 192XV UT WOS:000080105801132 ER PT J AU Wang, G Volkow, ND Fowler, JS Franceschi, D Thanos, PK Scherbaum, N Pappas, NR Wong, CT Hitzemann, RJ Felder, CA AF Wang, G Volkow, ND Fowler, JS Franceschi, D Thanos, PK Scherbaum, N Pappas, NR Wong, CT Hitzemann, RJ Felder, CA TI Effects of acute oral ethanol administration on regional brain glucose. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Brookhaven Natl Lab, Dept Med, Upton, NY 11973 USA. Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. SUNY Stony Brook, Stony Brook, NY 11794 USA. Univ Essen Gesamthsch, Dept Psychiat, Essen, Germany. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1999 VL 40 IS 5 SU S MA 1217 BP 275P EP 275P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 192XV UT WOS:000080105801131 ER PT J AU Groch, MW Erwin, WD Spies, SM Groch, PJ Marshall, RC AF Groch, MW Erwin, WD Spies, SM Groch, PJ Marshall, RC TI A quantitative three dimensional analysis program for gated blood pool SPECT. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Northwestern Univ, Chicago, IL 60611 USA. Lawrence Berkeley Lab, Berkeley, CA USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1999 VL 40 IS 5 SU S MA 1278 BP 290P EP 290P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 192XV UT WOS:000080105801192 ER PT J AU Logan, J Levy, AV Lee, JH Hode, F Felder, CA Alexoff, DL Fowler, JS Springer, CS AF Logan, J Levy, AV Lee, JH Hode, F Felder, CA Alexoff, DL Fowler, JS Springer, CS TI Properties of images produced from the combination in Fourier space of low resolution PET with high resolution (1)H(2)0 MR. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Brookhaven Natl Lab, Upton, NY 11973 USA. RI Lee, Jing-Huei/J-3978-2016 OI Lee, Jing-Huei/0000-0001-9921-7629 NR 0 TC 0 Z9 0 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1999 VL 40 IS 5 SU S MA 1301 BP 295P EP 295P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 192XV UT WOS:000080105801214 ER PT J AU Behr, TM Behe, M Stabin, MG Wehrmann, E Apostolidis, C Molinet, R Koch, L Goldenberg, DM Becker, W AF Behr, TM Behe, M Stabin, MG Wehrmann, E Apostolidis, C Molinet, R Koch, L Goldenberg, DM Becker, W TI Experimental studies on the therapeutic efficacy and toxicity of alpha- as compared to beta-emitters in radioimmunotherapy. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Univ Gottingen, D-3400 Gottingen, Germany. Oak Ridge Inst Sci & Educ, Oak Ridge, TN USA. European Inst Transuranium Elements, Karlsruhe, Germany. Garden State Canc Ctr, Belleville, NJ USA. RI Behe, Martin/E-2941-2013 NR 0 TC 0 Z9 0 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1999 VL 40 IS 5 SU S MA 1375 BP 313P EP 313P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 192XV UT WOS:000080105801288 ER PT J AU Behr, TM Sgouros, G Stabin, MG Behe, M Angerstein, C Blumenthal, RD Apostolidis, C Molinet, R Sharkey, RM Koch, L Goldenberg, DM Becker, W AF Behr, TM Sgouros, G Stabin, MG Behe, M Angerstein, C Blumenthal, RD Apostolidis, C Molinet, R Sharkey, RM Koch, L Goldenberg, DM Becker, W TI Factors influencing the radiation-induced myelotoxicity of beta-, auger conversion electron-, or alpha-emitters. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Univ Goettingen, Goettingen, Germany. Mem Sloan Kettering Canc Ctr, New York, NY 10021 USA. Oak Ridge Inst Sci & Educ, Oak Ridge, TN USA. Garden State Canc Ctr, Belleville, NJ USA. Commiss European Communities, Joint Res Ctr, European Inst Transuranium Elements, D-7500 Karlsruhe, Germany. RI Behe, Martin/E-2941-2013 NR 0 TC 0 Z9 0 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1999 VL 40 IS 5 SU S MA 1380 BP 314P EP 314P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 192XV UT WOS:000080105801293 ER PT J AU Guhlke, S Scheithauer, S Bender, H Knapp, FF Biersack, HJ AF Guhlke, S Scheithauer, S Bender, H Knapp, FF Biersack, HJ TI Rhenium-188 DMSa: In-vitro and in-vivo evaluation of the individual stereoisomers. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Oak Ridge Natl Lab, Oak Ridge, TN USA. Clin Nucl Med, Bonn, Germany. NR 0 TC 0 Z9 0 U1 1 U2 2 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1999 VL 40 IS 5 SU S MA 1384 BP 315P EP 315P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 192XV UT WOS:000080105801297 ER PT J AU Runge, R Andreeff, M Kropp, J Wunderlich, G Knapp, FF Franke, WG AF Runge, R Andreeff, M Kropp, J Wunderlich, G Knapp, FF Franke, WG TI Two years experience with quality control of the tungsten-188/rhenium-188 generator with high levels of activity. SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 Oak Ridge Natl Lab, Oak Ridge, TN USA. Univ Hosp, Dresden, Germany. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1999 VL 40 IS 5 SU S MA 1385 BP 316P EP 316P PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 192XV UT WOS:000080105801298 ER PT J AU Wang, GJ Volkow, ND Levy, AV Felder, CA Fowler, JS Pappas, NR Hitzemann, RJ Wong, CT AF Wang, GJ Volkow, ND Levy, AV Felder, CA Fowler, JS Pappas, NR Hitzemann, RJ Wong, CT TI Measuring reproducibility of regional brain metabolic responses to lorazepam using statistical parametric maps SO JOURNAL OF NUCLEAR MEDICINE LA English DT Article DE benzodiazepines; cerebral glucose metabolism; fluorodeoxyglucose; PET; statistical parametric mapping ID POSITRON-EMISSION-TOMOGRAPHY; BLOOD-FLOW; ACTIVATION; PET; VARIABILITY; ALCOHOLICS AB Statistical parametric mapping (SPM) is a method for localizing differences in brain activation patterns without the need for anatomic predefined constraints. The purpose of this study was to assess the reproducibility of the patterns of activation obtained with SPM for baseline measures and for metabolic changes in response to lorazepam on a test-retest design. The results were compared with those we previously published using region-of-interest (ROI) methods. Methods: Sixteen healthy right-handed men were scanned twice with PET and [F-18]fluorodeoxyglucose (FDG): before placebo and before lorazepam (30 mu g/kg). The same double FDG procedure was repeated 6-8 wk later to assess test-retest reproducibility. Image datasets were analyzed by using SPM95 software. Difference images between baseline and lorazepam were compared for the first and second evaluations, both for relative decreases as well as increases in metabolism. Significance level was systematically varied to P < 0.001, P < 0.01 and P < 0.05. Results: There were no differences in the baseline SPM maps obtained for the first and second evaluations. SPM showed similar, although not identical, differences in response to lorazepam between the two evaluations. Both evaluations showed significant decreases in occipital cortex (9.7% and 10%) and significant relative increases in left temporal pole (6.8% and 10.4%). However, the second evaluation showed a decrease in the left frontal cortex (areas 6 and 8), which was not present in the first evaluation. The results were very similar to those we had obtained with ROI methods, except for the activation in the left temporal pole, which we had not observed with ROI analyses. Conclusion: Although the overall pattern of lorazepam-induced activation depicted by SPM was reproducible in pattern and magnitude, there were some differences that included a left frontal area of deactivation during the second but not the first evaluation. Results with SPM are similar to those with the ROI method, and, because it systematically analyses the whole brain, SPM can uncover patterns not seen with the ROI method. C1 Brookhaven Natl Lab, Dept Med, Upton, NY 11973 USA. Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. SUNY Stony Brook, Dept Radiol, Stony Brook, NY 11794 USA. SUNY Stony Brook, Dept Psychiat, Stony Brook, NY 11794 USA. Vet Affairs Med Ctr, Psychiat Serv, Northport, NY USA. RP Wang, GJ (reprint author), Brookhaven Natl Lab, Dept Med, Upton, NY 11973 USA. FU NIAAA NIH HHS [1RO1 AA09481-01]; NIDA NIH HHS [5RO1 DA/MH09971] NR 29 TC 15 Z9 15 U1 0 U2 2 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 USA SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1999 VL 40 IS 5 BP 715 EP 720 PG 6 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 192QD UT WOS:000080089600008 PM 10319741 ER PT J AU Tkachuk, AM Ivanova, SE Isaenko, LI Eliseev, AP Krupke, V Payne, S Solarts, R Nostrad, M Page, R Payne, S AF Tkachuk, AM Ivanova, SE Isaenko, LI Eliseev, AP Krupke, V Payne, S Solarts, R Nostrad, M Page, R Payne, S TI Dy3+-doped crystals of double chlorides and double fluorides as the active media of IR solid-state lasers and telecommunication amplifiers SO JOURNAL OF OPTICAL TECHNOLOGY LA English DT Letter ID RELAXATION AB A comparative spectroscopic study of Dy3+-doped crystals of double chlorides KPb2Cl5:Dy3+ and double fluorides LiYF4:Dy3+ grown by the Bridgman-Stockbarger method has been carried out. The spectra of the absorption cross sections have been studied, and the Judd-Ofelt method has been used to determine the intensity parameters, On the basis of estimates of the probabilities of radiative and nonradiative transitions in the dysprosium ion and an experimental study of the luminescence spectra, it has been concluded that YLF:Dy3+ and YLF:Dy3+, Yb3+ crystals can be regarded as promising active media for 3-mu m lasers with diode pumping and that KPb2Cl5:Dy3+ and KPb2Cl5:Dy3+, Yb3+ crystals are unique in the number of radiative transitions in the dysprosium ion, including the IR region of the spectrum, all the way to 4 mu m The effect of amplification at a wavelength of 1.319 mu m obtained in them indicates that they can be used in practice as new active media in telecommunication amplifiers and lasers. (C) 1999 The Optical Society of America. [S1070-9762(99)02005-9]. C1 SI Vavilov State Opt Inst, St Petersburg, Russia. St Petersburg State Univ, Dept Phys, Petrodvorets, Russia. Russian Acad Sci, Siberian Branch, Technol Inst Single Crystals, Novosibirsk, Russia. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Tkachuk, AM (reprint author), SI Vavilov State Opt Inst, St Petersburg, Russia. RI Isaenko, Ludmila/H-7620-2013; Isaenko, Ludmila/A-5272-2014 NR 9 TC 12 Z9 13 U1 0 U2 4 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1070-9762 J9 J OPT TECHNOL+ JI J. Opt. Technol. PD MAY PY 1999 VL 66 IS 5 BP 460 EP 462 DI 10.1364/JOT.66.000460 PG 3 WC Optics SC Optics GA 204TP UT WOS:000080780800020 ER PT J AU Dohrmann, CR Robinett, RD AF Dohrmann, CR Robinett, RD TI Dynamic programming method for constrained discrete-time optimal control SO JOURNAL OF OPTIMIZATION THEORY AND APPLICATIONS LA English DT Article DE optimal control; dynamic programming; interior-point methods; sequential quadratic programming ID NEWTON METHOD; INEQUALITY CONSTRAINTS; IMPLEMENTATIONS; SYSTEMS AB A dynamic programming method is presented for solving constrained, discrete-time, optimal control problems. The method is based on an efficient algorithm for solving the subproblems of sequential quadratic programming. By using an interior-point method to accommodate inequality constraints, a modification of an existing algorithm for equality constrained problems can be used iteratively to solve the subproblems. Two test problems and two application problems are presented. The application examples include a rest-to-rest maneuver of a flexible structure and a constrained brachistochrone problem. C1 Sandia Natl Labs, Struct Dynam Dept, Albuquerque, NM 87185 USA. Sandia Natl Labs, Intelligent Syst Sensors & Controls Dept, Albuquerque, NM 87185 USA. RP Dohrmann, CR (reprint author), Sandia Natl Labs, Struct Dynam Dept, POB 5800, Albuquerque, NM 87185 USA. NR 20 TC 10 Z9 12 U1 1 U2 3 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0022-3239 J9 J OPTIMIZ THEORY APP JI J. Optim. Theory Appl. PD MAY PY 1999 VL 101 IS 2 BP 259 EP 283 DI 10.1023/A:1021733425632 PG 25 WC Operations Research & Management Science; Mathematics, Applied SC Operations Research & Management Science; Mathematics GA 202UK UT WOS:000080670400002 ER PT J AU Abdallah, J Faenov, AY Pikuz, TA Wilke, MD Kyrala, GA Clark, REH AF Abdallah, J Faenov, AY Pikuz, TA Wilke, MD Kyrala, GA Clark, REH TI Hot electron effects on the satellite spectrum of laser-produced plasmas SO JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER LA English DT Article ID RESONANCE LINE SATELLITES; HE-LIKE IONS; ALUMINUM PLASMA; BE-LIKE; SPECTROSCOPY; TRANSITIONS; EMISSION; TRIDENT; DENSITY AB In laser-produced plasmas, the interaction of the intense laser light with plasma electrons can produce high-energy superthermal electrons with energies in the keV range. These hot electrons can influence the level populations which determine spectral line structure. In the present paper, the effect of hot electrons on the X-ray satellite spectrum of laser-produced plasmas is studied. Calculated spectra are compared with experimental observations. Magnesium targets irradiated by three different types of laser pulses are considered. These include, a high-intensity 600 fs Nd-glass laser, a 1 ns Nd-glass laser, and a 2 ns CO2 laser. The Nd-glass laser experiments were conducted recently at the Los Alamos Trident Facility and the CO2 data were recorded by MISDC. High-resolution spectra were measured near the He-like resonance line of magnesium. The calculations employ an electron energy distribution which includes a thermal and a hot electron component, as part of a detailed collisional-radiative model. Plasma parameters including electron temperature, density, and hot electron fraction are estimated by choosing best fits to the experimental measurements. The calculations show that hot electrons can cause several anomalous effects. The Li-like jkl, abcd, and qr satellites can show intensities which are generally attributed to electron densities in excess of 10(23) cm(-3). In addition, the relative amplitude of the intercombination line can be unusually large even at high electron densities due to enhanced collisional excitation of the ls2p(3)P state by hot electrons. (C) 1999 Elsevier Science Ltd. All rights reserved. C1 NPO VNIIFTRI, MISDC, Mendeleevo 141570, Moscow Region, Russia. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Faenov, AY (reprint author), NPO VNIIFTRI, MISDC, Mendeleevo 141570, Moscow Region, Russia. NR 24 TC 23 Z9 23 U1 1 U2 2 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 MAY PY 1999 VL 62 IS 1 BP 1 EP 11 DI 10.1016/S0022-4073(97)00180-5 PG 11 WC Optics; Spectroscopy SC Optics; Spectroscopy GA 178WG UT WOS:000079291700001 ER PT J AU Abdallah, J Clark, REH Faenov, AY Karpinski, L Pikuz, SA Romanova, VM Sadowski, M Scholz, M Szydlowski, A AF Abdallah, J Clark, REH Faenov, AY Karpinski, L Pikuz, SA Romanova, VM Sadowski, M Scholz, M Szydlowski, A TI Electron beam effects on the spectroscopy of multiply charged ions in plasma focus experiments SO JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER LA English DT Article AB Argon-hydrogen mixture plasma focus experiments performed at the Warsaw Institute of Plasma Physics and Laser Microfusion show detailed space resolved spectra for Ar K-shell satellite lines up to F-like Ar and K-alpha of Ar. These transitions originating from autoionizing levels are caused by collisions of ions with the energetic electron beams which are created by the constrictions of the plasma column due to the development of magnetohydrodynamic instabilities. A collisional-radiative model was constructed using a non-Maxwellian electron energy distribution consisting of a thermal Maxwellian part plus a Gaussian part to represent the high-energy electron beam. The shapes of the observed satellite structures are consistent with the calculated spectrum for electron temperatures between 20 and 230 eV, and beam densities of about 10(-3) times the plasma electron density. (C) 1999 Elsevier Science Ltd. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Atom & Opt Phys Grp, Los Alamos, NM 87545 USA. Univ Calif Los Angeles, Plasma Phys Lab, Los Angeles, CA 90095 USA. NPO VNIIFTRI, MISDC, Mendeleevo 141570, Moscow Region, Russia. Inst Plasma Phys & Laser Microfus, Warsaw, Poland. PN Lebedev Phys Inst, Moscow, Russia. Soltan Inst Nucl Studies, PL-00681 Warsaw, Poland. RP Abdallah, J (reprint author), Univ Calif Los Alamos Natl Lab, Atom & Opt Phys Grp, T-4 MS B212,POB 1663, Los Alamos, NM 87545 USA. RI Pikuz, Sergey/M-8231-2015; Romanova, Vera/M-6922-2015 NR 14 TC 27 Z9 28 U1 3 U2 10 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 MAY PY 1999 VL 62 IS 1 BP 85 EP 96 DI 10.1016/S0022-4073(98)00073-9 PG 12 WC Optics; Spectroscopy SC Optics; Spectroscopy GA 178WG UT WOS:000079291700007 ER PT J AU Zhao, L Johnson, E Robinson, L AF Zhao, L Johnson, E Robinson, L TI The neutron flux of a Cf-252 neutron activation analysis device using the MCNP code SO JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY LA English DT Article AB This report presents results from the application of the Monte Carlo N-Particle (MCNP) computer code to the Cf-252 neutron activation analysis (NAA) Device in the Technical Physics Institute of the Heilongjiang Science Academy of the People's Republic of China. The thermal and epithermal neutron flux at the sample positions and the neutron and photon fluxes on the surfaces of the device were calculated. A comparison between the calculated and experimental thermal and epithermal neutron fluxes at sample positions yield relative errors of less than 10% for the thermal neutron flux. C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. Florida A&M Univ, Inst Environm Sci, Tallahassee, FL 32307 USA. NR 6 TC 1 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0236-5731 J9 J RADIOANAL NUCL CH JI J. Radioanal. Nucl. Chem. PD MAY PY 1999 VL 240 IS 2 BP 531 EP 534 DI 10.1007/BF02349409 PG 4 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 197AN UT WOS:000080342600025 ER PT J AU Chamberlin, RM Abney, KD AF Chamberlin, RM Abney, KD TI Strontium and cesium extraction into hydrocarbons using alkyl cobalt dicarbollide and polyethylene glycols SO JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY LA English DT Article ID DERIVATIVES AB The extraction of strontium and cesium ions from high ionic strength acid, base, and salt solutions into an organic extractant consisting of alkyl cobalt dicarbollide and polyethylene glycol (PEG) in diethylbenzene was investigated. Adding hexaethylene glycol or PEG-400 improved the strontium extraction greater than or equal to 100-fold, while cesium extraction was decreased at high PEG concentrations. The extractions are rapid and selective, even in the presence of molar concentrations of sodium ion, suggesting that alkyl cobalt dicarbollide extractants are useful for the treatment of alkaline nuclear wastes. A method for the synthesis of tetra-n-hexyl(cobalt dicarbollide) is described. C1 Univ Calif Los Alamos Natl Lab, Dept Chem Sci & Technol, Los Alamos, NM 87545 USA. RP Chamberlin, RM (reprint author), Univ Calif Los Alamos Natl Lab, Dept Chem Sci & Technol, CST-11,MS J514, Los Alamos, NM 87545 USA. RI Chamberlin, Rebecca/A-1335-2011 OI Chamberlin, Rebecca/0000-0001-6468-7778 NR 14 TC 6 Z9 6 U1 0 U2 1 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0236-5731 J9 J RADIOANAL NUCL CH JI J. Radioanal. Nucl. Chem. PD MAY PY 1999 VL 240 IS 2 BP 547 EP 553 DI 10.1007/BF02349412 PG 7 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 197AN UT WOS:000080342600028 ER PT J AU Dewberry, RA Boyce, WT AF Dewberry, RA Boyce, WT TI Plutonium measurements in Hanford DOE site waste samples SO JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY LA English DT Article AB This paper describes development work to prepare a method to measure absolute Pu-239 content and Pu-isotopics by ICP-MS in acidified Hanford DOE-site samples which are very high in Sr-90, Tc-99, and Cs-137 radioactivity and which are frequently high in organic carbon content. Samples with very large Sr-90 and Cs-137 contents have historically been difficult to analyze for Pu content by each of three alpha-counting techniques in use at SRS, and analysis by ICP-MS in these samples is complicated by the high organics content. We report an ion exchange chemical preparation to obtain fraction of Pu that does not contain any fission product contribution and no interfering organics to allow measure of absolute Pu-239 and of Pu-239 through Pu-241 isotopics by ICP-MS. The method uses a Pu-242 spike to measure Pu recovery and is demonstrated in this paper with three distinct commercially available resins and with over 300 samples. Measured absolute Pu-239 contents in sixty-three spiked/unspiked duplicates have agreed within 15% precision. Overall Pu-242 recoveries were near 90% with 25% precision. Comparisons of absolute Pu-239 contents measured directly on three samples agreed within the quoted 25% uncertainty. C1 Westinghouse Savannah River Co, Savannah River Technol Ctr, Aiken, SC 29808 USA. RP Dewberry, RA (reprint author), Westinghouse Savannah River Co, Savannah River Technol Ctr, 773-A, Aiken, SC 29808 USA. NR 8 TC 3 Z9 3 U1 1 U2 1 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0236-5731 J9 J RADIOANAL NUCL CH JI J. Radioanal. Nucl. Chem. PD MAY PY 1999 VL 240 IS 2 BP 643 EP 650 DI 10.1007/BF02349426 PG 8 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA 197AN UT WOS:000080342600042 ER PT J AU Silbert, LE Melrose, JR AF Silbert, LE Melrose, JR TI The rheology and microstructure of concentrated, aggregated colloids SO JOURNAL OF RHEOLOGY LA English DT Article ID SHEAR-INDUCED ORDER; COMPUTER-SIMULATIONS; BROWNIAN SUSPENSIONS; DYNAMIC SIMULATION; HARD-SPHERES; PAIR-DRAG; DISPERSIONS; MODEL; MOTION; FORCES AB The rheology of concentrated, aggregated colloidal suspensions is determined through particulate simulations. Aggregating systems experience a large viscous enhancement over nonaggregating systems, this being due to the increase in the component of the viscosity arising from the repulsive colloid (thermodynamic) forces when attractive forces are present. The shear behavior of aggregating systems, for colloid volume fraction 0.47 less than or equal to phi(c) less than or equal to 0.57, is characterized in the steady state regime over a wide range in shear rate, and is found to be power law, shear thinning eta similar to f(phi(c)) (gamma) over dot (-alpha) , where the shear thinning index alpha = 0.84 +/- 0.01. The effect of volume fraction enters as f(phi(c)) = (1- phi c/phi(max))(-1) with phi(max) = 0.64, the value of random close packing; similarly, the viscosity also scales with the potential well depth as a power law, of index . Consequently, we are able to deduce the full constitutive relation for this power law behavior. The associated structural features which emerge as a result of the imposed shear are identified with the rheology. The shear thinning regime crosses over into a state of ordered phase flow at high shear rates likewise simulations of hard sphere fluids. We also show that the high-shear ordered configurations appear to be a function of colloid concentration, with a transition from string phase order through to layered phases as phi(c) increases. (C) 1999 The Society of Rheology. [S0148-6055(99)00603-3]. C1 Univ Cambridge, Cavendish Lab, Polymers & Colloids Grp, Cambridge CB3 0HE, England. Univ Warwick, Dept Phys, Coventry CV4 7AL, W Midlands, England. RP Silbert, LE (reprint author), Sandia Natl Labs, POB 5800,MS 1349, Albuquerque, NM 87185 USA. NR 52 TC 35 Z9 36 U1 2 U2 16 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0148-6055 J9 J RHEOL JI J. Rheol. PD MAY-JUN PY 1999 VL 43 IS 3 BP 673 EP 700 DI 10.1122/1.551028 PG 28 WC Mechanics SC Mechanics GA 194ZP UT WOS:000080224900011 ER PT J AU Bornick, RM Stacy, AM Taylor, RD Kwei, GH AF Bornick, RM Stacy, AM Taylor, RD Kwei, GH TI An investigation of the europium valence in EuCu1.75P2 by Eu Mossbauer and Eu L-III-Edge X-ray absorption spectroscopy SO JOURNAL OF SOLID STATE CHEMISTRY LA English DT Article ID THCR2SI2 TYPE-STRUCTURE; PHOSPHIDES AB The europium valence for EuCu1.75P2 is examined by Eu Mossbauer spectroscopy and Eu L-III-edge X-ray absorption spectroscopy, On the basis of previous measurements of related phases with the ThCr2Si2 structure-type, the europium valence in EuCu1.75P2 is expected to be intermediate valent or trivalent, In contrast, divalent europium is observed. This result is explained on the basis of a band argument in which the conduction band is filled, and thus, there is an extra electron in the Eu 4f(7) state. (C) 1999 Academic Press. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Univ Calif Los Alamos Natl Lab, Condensed Matter & Thermal Phys Grp, Los Alamos, NM 87545 USA. RP Stacy, AM (reprint author), Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. NR 10 TC 3 Z9 3 U1 0 U2 0 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0022-4596 J9 J SOLID STATE CHEM JI J. Solid State Chem. PD MAY PY 1999 VL 144 IS 2 BP 252 EP 254 DI 10.1006/jssc.1997.7622 PG 3 WC Chemistry, Inorganic & Nuclear; Chemistry, Physical SC Chemistry GA 194FK UT WOS:000080181300004 ER PT J AU Field, MD Kennedy, BJ Hunter, BA Vogt, T AF Field, MD Kennedy, BJ Hunter, BA Vogt, T TI Temperature-dependent structural behavior of Bi0.5Nd1.5Ru2O7 SO JOURNAL OF SOLID STATE CHEMISTRY LA English DT Article ID CRYSTAL-STRUCTURE; PYROCHLORES AB The structure of the Bi-doped pyrochlore, Bi0.5Nd1.5Ru2O7 has been studied between 20 and 300 K using powder synchrotron diffraction methods. The structure shows an abupt change in the Bi(Nd)-O and and Ru-O contacts near 200 K as a consequence of a metal-semiconductor transition. There is a marked hysteresis in the structural parameters upon rewarming the sample. (C) 1999 Academic Press. C1 Univ Sydney, Sch Chem, Sydney, NSW 2006, Australia. Neutron Scattering Grp, Menai, NSW 2234, Australia. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Field, MD (reprint author), Univ Sydney, Sch Chem, Sydney, NSW 2006, Australia. RI Vogt, Thomas /A-1562-2011; OI Vogt, Thomas /0000-0002-4731-2787; Kennedy, Brendan/0000-0002-7187-4579 NR 11 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 0022-4596 J9 J SOLID STATE CHEM JI J. Solid State Chem. PD MAY PY 1999 VL 144 IS 2 BP 467 EP 469 DI 10.1006/jssc.1999.8171 PG 3 WC Chemistry, Inorganic & Nuclear; Chemistry, Physical SC Chemistry GA 194FK UT WOS:000080181300034 ER PT J AU Moore, RC Borkowski, M Bronikowski, MG Chen, JF Pokrovsky, OS Xia, YX Choppin, GR AF Moore, RC Borkowski, M Bronikowski, MG Chen, JF Pokrovsky, OS Xia, YX Choppin, GR TI Thermodynamic modeling of actinide complexation with acetate and lactate at high ionic strength SO JOURNAL OF SOLUTION CHEMISTRY LA English DT Article DE actinides; acetate; lactate; complexation; Pitzer parameters ID NACL MEDIA; PARAMETERS; HYDROLYSIS; SOLUBILITY AB The stability constants of NpO2+, UO22+ Am3+, and Th4+ with acetate and lactate anions has been measured in 0.3-5.0m NaCl media at 25 degrees C by the solvent extraction technique. For the 1:1 complexation, the values of the stability constants increased in the order: NpO2+ < Am3+ < UO22+ < Th4+, in accordance with the actinide charge density and reflecting the strongly ionic bonding of the complexes. The Pitzer ionic interaction parameters were calculated and used to estimate the thermodynamic stability constants at I = 0. Because our data were collected mainly in the high ionic strength region values of beta((1)) were estimated from values reported in the literature. For all stability constants the Pitzer model gives an excellent representation of the data using three interaction parameters beta((0)), beta((1)) and C-phi. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Florida State Univ, Dept Chem, Tallahassee, FL 32306 USA. RP Moore, RC (reprint author), Sandia Natl Labs, MS 0733, Albuquerque, NM 87185 USA. OI Pokrovsky, Oleg/0000-0002-3155-7069 NR 27 TC 23 Z9 23 U1 6 U2 15 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0095-9782 J9 J SOLUTION CHEM JI J. Solut. Chem. PD MAY PY 1999 VL 28 IS 5 BP 521 EP 531 DI 10.1023/A:1022678814904 PG 11 WC Chemistry, Physical SC Chemistry GA 222WZ UT WOS:000081809500004 ER PT J AU Felmy, AR Rai, D AF Felmy, AR Rai, D TI Application of Pitzer's equations for modeling the aqueous thermodynamics of actinide species in natural waters: A review SO JOURNAL OF SOLUTION CHEMISTRY LA English DT Article DE actinides; thermodynamic data; Pitzer ion-interaction parameters; trivalent actinides; tetravalent actinides; pentavalent actinides; hexavalent actinides ID CONCENTRATED SALT-SOLUTIONS; U(IV) HYDROUS OXIDES; CARBONATE COMPLEXATION; HYDROLYSIS CONSTANTS; NA2CO3 SOLUTIONS; IONIC-STRENGTH; SOLUBILITY; ELECTROLYTES; SYSTEM; NEPTUNIUM(V) AB A review of the applicability of Fitter's equations to the aqueous thermodynamics of actinide species in natural waters is presented. This review includes a brief historical perspective on the application of Fitter's equations to actinides, information on the difficulties and complexities of studying and modeling the different actinide oxidation states, and a discussion of the use of chemical analogs for different actinide oxidation states. Included are tables of Pitzer ion-interaction parameters and associated standard stare equilibrium constants for each actinide oxidation state. These data allow the modeling of the aqueous thermodynamics of different actinide oxidation states to high ionic strength. C1 Pacific NW Lab, Richland, WA 99352 USA. RP Felmy, AR (reprint author), Pacific NW Lab, Battelle Blvd,POB 999, Richland, WA 99352 USA. NR 50 TC 26 Z9 26 U1 2 U2 14 PU KLUWER ACADEMIC/PLENUM PUBL PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0095-9782 J9 J SOLUTION CHEM JI J. Solut. Chem. PD MAY PY 1999 VL 28 IS 5 BP 533 EP 553 DI 10.1023/A:1022630931742 PG 21 WC Chemistry, Physical SC Chemistry GA 222WZ UT WOS:000081809500005 ER PT J AU Luo, Y AF Luo, Y TI Shared memory vs. message passing: the COMOPS benchmark experiment SO JOURNAL OF SUPERCOMPUTING LA English DT Article DE shared memory; message passing; MPI; distributed computing; performance evaluation AB This paper presents the comparison of the COMOPS benchmark performance in MPI and shared memory on four different shared memory platforms: the DEC AlphaServer 8400/300, the SGI Power Challenge, the SGI Origin2000, and the HP-Convex Exemplar SPP1600. The paper also qualitatively analyzes the obtained performance data based on an understanding of the corresponding architecture and the MPI implementations. Some conclusions are made for the inter-processor communication performance on these four shared memory platforms. C1 Univ Calif Los Alamos Natl Lab, Sci Comp Grp, Los Alamos, NM 87545 USA. RP Luo, Y (reprint author), Univ Calif Los Alamos Natl Lab, Sci Comp Grp, CIC-19,Mail Stop B256, Los Alamos, NM 87545 USA. NR 12 TC 0 Z9 0 U1 0 U2 0 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0920-8542 J9 J SUPERCOMPUT JI J. Supercomput. PD MAY PY 1999 VL 13 IS 3 BP 283 EP 301 DI 10.1023/A:1008009103962 PG 19 WC Computer Science, Hardware & Architecture; Computer Science, Theory & Methods; Engineering, Electrical & Electronic SC Computer Science; Engineering GA 204EC UT WOS:000080749600004 ER PT J AU Gustafson, JL Todi, R AF Gustafson, JL Todi, R TI Conventional benchmarks as a sample of the performance spectrum SO JOURNAL OF SUPERCOMPUTING LA English DT Article DE performance analysis; benchmarks; hierarchical memory; HINT AB Most benchmarks are smaller than actual application programs. One reason is to improve benchmark universality by demanding resources every computer is likely to have. However, users dynamically increase the size of application programs to match the power available, whereas most benchmarks are static and of a size appropriate for computers available when the benchmark was created; this is particularly true for parallel computers. Thus, the benchmark overstates computer performance, since smaller problems spend more time in cache. Scalable benchmarks, such as HINT, examine the full spectrum of performance through various memory regimes, and express a superset of the information given by any particular fixed-size benchmark. Using 5,000 experimental measurements, we have found that performance on the NAS Parallel Benchmarks, SPEC, LINPACK, and other benchmarks is predicted accurately by subsets of HINT performance curve. Correlations are typically better than 0.995. Predicted ranking is often perfect. C1 US DOE, Ames Lab, Washington, DC 20585 USA. RP Gustafson, JL (reprint author), US DOE, Ames Lab, Washington, DC 20585 USA. NR 10 TC 8 Z9 8 U1 0 U2 0 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0920-8542 J9 J SUPERCOMPUT JI J. Supercomput. PD MAY PY 1999 VL 13 IS 3 BP 321 EP 342 DI 10.1023/A:1008013204871 PG 22 WC Computer Science, Hardware & Architecture; Computer Science, Theory & Methods; Engineering, Electrical & Electronic SC Computer Science; Engineering GA 204EC UT WOS:000080749600006 ER PT J AU Pietraski, PJ Voltz, P Furenlid, LR AF Pietraski, PJ Voltz, P Furenlid, LR TI Sequence estimation of piled-up pulses in synchrotron-based XAFS SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 10th International Conference on XAFS (XAFS X) CY AUG 10-14, 1998 CL ILLINOIS INST TECHNOL, CHICAGO, ILLINOIS HO ILLINOIS INST TECHNOL DE pile-up; time structure; detectors; inter-pulse interference AB Signal processing techniques are being developed that allow XAFS and diffraction experiments employing solid state detectors to be carried out at higher count rates by resolving shaper pulses that would otherwise be rejected or corrupted due to pile-up. This method exploits the time structure of the synchrotron generated radiation and a priori knowledge of the incident and fluorescence energies to perform sequence of event estimation based on periodically sampled observations of the shaper amplifier output. Isolated pulses are processed with a simple threshold decision much like an SCA while non-isolated pulses that produce sequence segments of finite length are processed as vectors. Once the vector is estimated, the number of fluorescence and scatter events is counted. Since these piled-up pulses are not rejected, the over all count rate of the experiment is increased. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. Polytech Univ, Farmingdale, NY 11754 USA. RP Pietraski, PJ (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. NR 3 TC 2 Z9 2 U1 0 U2 0 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0909-0495 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD MAY 1 PY 1999 VL 6 BP 152 EP 154 DI 10.1107/S0909049598014599 PN 3 PG 3 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 212NA UT WOS:000081221700008 PM 15263230 ER PT J AU Zhong, Z Chapman, D Bunker, B Bunker, G Fischetti, R Segre, C AF Zhong, Z Chapman, D Bunker, B Bunker, G Fischetti, R Segre, C TI A bent Laue analyzer for fluorescence EXAFS detection SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 10th International Conference on XAFS (XAFS X) CY AUG 10-14, 1998 CL ILLINOIS INST TECHNOL, CHICAGO, ILLINOIS HO ILLINOIS INST TECHNOL DE crystal analyzer; fluorescence detector; bent crystal ID MONOCHROMATOR; RADIOGRAPHY AB An analyzer for detection of fluorescence radiation was developed for fluorescence XAFS of dilute samples at energies above 13 keV. The analyzer is a bent Laue crystal of logarithmic spiral shape. The K fluorescence lines can be collected with a large solid angle and moderate reflectivity using the asymmetric [111] reflection of silicon crystals of 200 micron thick. Tuning of the analyzer diffraction energies for different samples can be made with one adjustment. Experiment was performed at the APS BioCAT ID beamline using a silicon crystal bent to an average radius of 200 mm to diffract silver fluorescence x-rays. The crystal (35 mm by 120 mm active area) covers a solid angle of 0.1 SR of the sample fluorescence. The measured reflectivity was 10%. C1 Brookhaven Natl Lab, NSLS, Upton, NY 11973 USA. IIT, CSRRI, Chicago, IL 60616 USA. Univ Notre Dame, Dept Phys, Notre Dame, IN 46556 USA. IIT, BioCAT Project, Chicago, IL 60616 USA. IIT, BCPS Dept, Chicago, IL 60616 USA. RP Zhong, Z (reprint author), Brookhaven Natl Lab, NSLS, Upton, NY 11973 USA. RI Segre, Carlo/B-1548-2009; ID, BioCAT/D-2459-2012 OI Segre, Carlo/0000-0001-7664-1574; NR 5 TC 32 Z9 36 U1 0 U2 9 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0909-0495 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD MAY 1 PY 1999 VL 6 BP 212 EP 214 DI 10.1107/S0909049599002022 PN 3 PG 3 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 212NA UT WOS:000081221700030 PM 15263252 ER PT J AU Zhang, K Rosenbaum, G Bunker, G AF Zhang, K Rosenbaum, G Bunker, G TI Design and testing of a prototype multilayer analyzer X-ray fluorescence detector SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 10th International Conference on XAFS (XAFS X) CY AUG 10-14, 1998 CL ILLINOIS INST TECHNOL, CHICAGO, ILLINOIS HO ILLINOIS INST TECHNOL DE X-ray fluorescence detector; synthetic multilayers AB It is a concern that multielement solid state detectors, commonly used for x-ray fluorescence detection on dilute systems, will not be optimal with the third generation sources due to their count rate limitations and the high photon flux from the source. As an alternative, we are developing energy-resolving x-ray fluorescence detectors using synthetic multilayers. In this paper, we present the design and testing of a prototype multilayer array detector that consists of three elements of graded multilayers. The tests show that the elements can be accurately aligned relative to each other, and the instrument can be easily tuned to other fluorescence energies once aligned. A background rejection rate of 40-50 times has been achieved with a throughput of 28-30 percent. C1 IIT, Chicago, IL 60616 USA. Argonne Natl Lab, Argonne, IL 60439 USA. RP Zhang, K (reprint author), IIT, Chicago, IL 60616 USA. RI ID, BioCAT/D-2459-2012 NR 2 TC 10 Z9 11 U1 0 U2 1 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0909-0495 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD MAY 1 PY 1999 VL 6 BP 220 EP 221 DI 10.1107/S0909049598018111 PN 3 PG 2 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 212NA UT WOS:000081221700033 PM 15263255 ER PT J AU Ankudinov, AL AF Ankudinov, AL TI Real-space multiple-scattering approach to XANES SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 10th International Conference on XAFS (XAFS X) CY AUG 10-14, 1998 CL ILLINOIS INST TECHNOL, CHICAGO, IL HO ILLINOIS INST TECHNOL DE XANES; electronic structure; multiple scattering theory ID ABSORPTION FINE-STRUCTURE; EXTENDED X-RAY; NEAR-EDGE STRUCTURE; ELECTRONIC-STRUCTURE; ORDER; POTENTIALS; TRANSITION; EXAFS AB The historical development of ideas in x-ray absorption and multiple scattering theory that lead to real space, multiple scattering (RSMS) calculations of XANES is reviewed. The RSMS method for both XANES and electronic structure calculations has several advantages with respect to other approaches. Recently developed RSMS codes now provide a way to interpret XANES in terms of structural and electronic information. The sensitivity of XANES calculations to muffin-tin potential construction, self-consistency and self-energy is demonstrated for the Ti K edge of PbTiO(3). Future RSMS electronic structure codes require several improvements, such as non-spherical potentials and inclusion of many body effects in order to achieve more quantitative agreement with experiment. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Ankudinov, AL (reprint author), Los Alamos Natl Lab, MST-11, Los Alamos, NM 87545 USA. EM alex@phys.washington.edu NR 40 TC 10 Z9 10 U1 0 U2 0 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 0909-0495 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD MAY 1 PY 1999 VL 6 BP 236 EP 238 DI 10.1107/S0909049598017099 PN 3 PG 3 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 212NA UT WOS:000081221700039 PM 15263261 ER PT J AU Newville, M Carroll, SA O'Day, PA Waychunas, GA Ebert, M AF Newville, M Carroll, SA O'Day, PA Waychunas, GA Ebert, M TI A web-based library of XAFS data on model compounds SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 10th International Conference on XAFS (XAFS X) CY AUG 10-14, 1998 CL ILLINOIS INST TECHNOL, CHICAGO, ILLINOIS HO ILLINOIS INST TECHNOL DE EXAFS data; web-based archive ID SPECTRA AB An archive of XAFS data collected on standard model compounds of transition metals has been constructed and made available by the world wide web. The data in this library have all been taken in transmission on powder samples free of thickness effects. Data are stored in individual files in a standardized ASCII column format. Fields describing the contents of files can be searched easily. The data are intended to provide standards for comparison of EXAFS analysis procedures, for empirical analysis of XANES features, and to test theoretical XANES calculations. Emphasis has been placed on inorganic transition metal compounds to assist the analysis of environmentally relevant samples. C1 Univ Chicago, Consortium Adv Radiat Sources, Chicago, IL 60637 USA. Univ Calif Lawrence Livermore Natl Lab, Environm Program, Livermore, CA USA. Arizona State Univ, Dept Geol, Tempe, AZ USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Earth Sci, Berkeley, CA 94720 USA. RP Newville, M (reprint author), Univ Chicago, Consortium Adv Radiat Sources, Chicago, IL 60637 USA. NR 5 TC 16 Z9 16 U1 0 U2 5 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0909-0495 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD MAY 1 PY 1999 VL 6 BP 276 EP 277 DI 10.1107/S0909049599000795 PN 3 PG 2 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 212NA UT WOS:000081221700055 PM 15263277 ER PT J AU Wasserman, SR Allen, PG Shuh, DK Bucher, JJ Edelstein, NM AF Wasserman, SR Allen, PG Shuh, DK Bucher, JJ Edelstein, NM TI EXAFS and principal component analysis: a new shell game SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 10th International Conference on XAFS (XAFS X) CY AUG 10-14, 1998 CL ILLINOIS INST TECHNOL, CHICAGO, ILLINOIS HO ILLINOIS INST TECHNOL DE principal component analysis; factor analysis; EXAFS; uranyl ID SPECTROSCOPY; IRON AB The use of principal component (factor) analysis for the interpretation of EXAFS spectra is described. The components derived from EXAFS spectra share mathematical properties with the original spectra. As a result, the abstract components can be analyzed using standard EXAFS methodology to yield bond distances and other coordination parameters. The number of components that must be analyzed is usually less than the number of original spectra. The method is demonstrated using a series of spectra from aqueous solutions of uranyl ions. C1 Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA. Univ Calif Lawrence Livermore Natl Lab, Seaborg Inst Transactinium Sci, Livermore, CA 94551 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA. RP Wasserman, SR (reprint author), Argonne Natl Lab, Adv Photon Source, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 7 TC 77 Z9 77 U1 3 U2 21 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0909-0495 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD MAY 1 PY 1999 VL 6 BP 284 EP 286 DI 10.1107/S0909049599000965 PN 3 PG 3 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 212NA UT WOS:000081221700058 PM 15263280 ER PT J AU Frenkel, AI AF Frenkel, AI TI Solving the structure of nanoparticles by multiple-scattering EXAFS analysis SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 10th International Conference on XAFS (XAFS X) CY AUG 10-14, 1998 CL ILLINOIS INST TECHNOL, CHICAGO, ILLINOIS HO ILLINOIS INST TECHNOL DE nanoparticles; particle size; EXAFS AB The particle size effect on the coordination number in nanoparticles is much stronger for more distant coordination shells than for the first nearest neighbor shell. We show, using the EXAFS analysis of carbon-supported Pt and Pt-Ru nanoparticles, that it is possible to analyze the structure of mono- and heteroatomic particles through the 4(th) shell by taking into account multiple scatterings, and by using multiple edge refinement in the case of Pt-Ru alloy. Combined with the transmission electron microscopy and electron diffraction results, our procedure enabled us to obtain the particle shape and size in both types of the nanoclusters, and non-statistical distribution of Pt and Ru atoms in the alloy. C1 Univ Illinois, Mat Res Lab, Urbana, IL 61801 USA. RP Frenkel, AI (reprint author), Brookhaven Natl Lab, Bldg 510E, Upton, NY 11973 USA. RI Frenkel, Anatoly/D-3311-2011 OI Frenkel, Anatoly/0000-0002-5451-1207 NR 8 TC 67 Z9 68 U1 3 U2 12 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0909-0495 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD MAY 1 PY 1999 VL 6 BP 293 EP 295 DI 10.1107/S0909049598017786 PN 3 PG 3 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 212NA UT WOS:000081221700061 PM 15263283 ER PT J AU Campbell, L Rehr, JJ Schenter, GK McCarthy, MI Dixon, D AF Campbell, L Rehr, JJ Schenter, GK McCarthy, MI Dixon, D TI XAFS Debye-Waller factors in aqueous Cr+3 from molecular dynamics SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 10th International Conference on XAFS (XAFS X) CY AUG 10-14, 1998 CL ILLINOIS INST TECHNOL, CHICAGO, IL HO ILLINOIS INST TECHNOL DE EXAFS; molecular dynamics; solvation; metal hydrates ID ABSORPTION FINE-STRUCTURE; 2ND HYDRATION SHELL; SPECTRA; WATER; ZN2+ AB Controversy exists on whether the second hydration shell of the aqueous chromium +3 cation is observable by XAFS. The problem is aggravated by strong first shell multiple scattering contributions competing with the second hydration shell signal. By finding ab initio values for nearly all free parameters in the theory, we greatly reduce the number of parameters to be fit, thus allowing an unambiguous resolution of this controversy. Quantum chemistry calculations yielded a parameterized force field model which was used in classical molecular dynamics simulations to calculate all the multiple scattering Debye-Waller factors. The self-consistent FEFF8 code fixes Eo to within 1 eV. The predicted spectrum is in good agreement with experiment. Fitted distances for the first and second hydration shell are 2.0008 +/- 0.0068 Angstrom and 3.914 +/- 0.096 Angstrom, respectively. The second shell is shown to be responsible for about 1/3 of the XAFS Fourier transformed signal at the position of the second shell. C1 Univ Washington, Dept Phys, Seattle, WA 98195 USA. Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Univ Washington, Dept Phys, Seattle, WA 98195 USA. EM iwcamp@u.washington.edu RI Schenter, Gregory/I-7655-2014 OI Schenter, Gregory/0000-0001-5444-5484 NR 18 TC 35 Z9 35 U1 0 U2 4 PU INT UNION CRYSTALLOGRAPHY PI CHESTER PA 2 ABBEY SQ, CHESTER, CH1 2HU, ENGLAND SN 1600-5775 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD MAY 1 PY 1999 VL 6 BP 310 EP 312 DI 10.1107/S0909049598018202 PN 3 PG 3 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 212NA UT WOS:000081221700068 PM 15263290 ER PT J AU Nelson, E Woicik, J Pianetta, P AF Nelson, E Woicik, J Pianetta, P TI Direct measurement of valence charge asymmetry in GaAs using X-ray standing waves SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 10th International Conference on XAFS (XAFS X) CY AUG 10-14, 1998 CL ILLINOIS INST TECHNOL, CHICAGO, ILLINOIS HO ILLINOIS INST TECHNOL DE X-ray standing waves; valence band photoemission spectroscopy; bond polarity ID SURFACE AB Through detection of valence photoelectrons, the technique of xray standing waves directly measured the charge asymmetry of the GaAs valence band. Using the back-reflection geometry for the (111) and (TTT) diffraction planes, we determine from the coherent distances of the standing waves, that a majority of the valence electrons reside on the As atoms of this heteropolar crystal. These measurements agree well with the GaAs bond polarity calculated from the values of the Hartree-Fock terms. In contrast, the valence standing waves for germanium determine the valence charge to be symmetric. The coherent fractions of the standing waves of Ge and GaAs are reduced compared to those of core-level standing waves, indicating the delocalization of valence charge. This technique using low energy x-rays together with valence photoelectron detection can be more generally applied to the study of chemical bonding. C1 Stanford Synchrotron Radiat Lab, Stanford, CA 94309 USA. NIST, Gaithersburg, MD 20899 USA. RP Nelson, E (reprint author), Stanford Synchrotron Radiat Lab, POB 4349,Mail Stop 99, Stanford, CA 94309 USA. NR 4 TC 1 Z9 1 U1 2 U2 4 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0909-0495 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD MAY 1 PY 1999 VL 6 BP 341 EP 343 DI 10.1107/S0909049598016537 PN 3 PG 3 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 212NA UT WOS:000081221700079 PM 15263301 ER PT J AU Heald, SM Brewe, DL Stern, EA Kim, KH Brown, FC Jiang, DT Crozier, ED Gordon, RA AF Heald, SM Brewe, DL Stern, EA Kim, KH Brown, FC Jiang, DT Crozier, ED Gordon, RA TI XAFS and micro-XAFS at the PNC-CAT beamlines SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 10th International Conference on XAFS (XAFS X) CY AUG 10-14, 1998 CL ILLINOIS INST TECHNOL, CHICAGO, ILLINOIS HO ILLINOIS INST TECHNOL DE beamline; advanced photon source; micro-XAFS AB The Pacific Northwest Consortium Collaborative Access Team (PNC-CAT) is constructing bending magnet and insertion device (ID) beamlines at the Advanced Photon Source. Both beamlines will be heavily used for XAFS and micro-XAFS experiments. This paper summarises their capabilities, and initial operational experience with the ID line. The ID beamline is based on APS undulator A, and has been running in an initial commissioning configuration since May 1997. Currently the undulator and monochromator energies can be scanned in synchrony for EXAFS measurements, and we have obtained focused beams as small as 0.7 micron using tapered capillaries. Initial testing has also begun on a MBE/UHV system for in-situ surface XAFS. C1 Pacific NW Natl Lab, Richland, WA USA. Univ Washington, Seattle, WA 98195 USA. Simon Fraser Univ, Burnaby, BC V5A 1S6, Canada. RP Heald, SM (reprint author), Bldg 435E,9700 S Cass Ave, Argonne, IL USA. NR 3 TC 75 Z9 75 U1 1 U2 8 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0909-0495 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD MAY 1 PY 1999 VL 6 BP 347 EP 349 DI 10.1107/S090904959801677X PN 3 PG 3 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 212NA UT WOS:000081221700081 PM 15263303 ER PT J AU Duff, MC Newville, M Hunter, DB Bertsch, PM Sutton, SR Triay, IR Vaniman, DT Eng, P Rivers, ML AF Duff, MC Newville, M Hunter, DB Bertsch, PM Sutton, SR Triay, IR Vaniman, DT Eng, P Rivers, ML TI Micro-XAS studies with sorbed plutonium on tuff SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 10th International Conference on XAFS (XAFS X) CY AUG 10-14, 1998 CL ILLINOIS INST TECHNOL, CHICAGO, ILLINOIS HO ILLINOIS INST TECHNOL DE micro-EXAFS; micro-XANES; micro-XRF; sorption; plutonium ID RAY-ABSORPTION-SPECTROSCOPY; FINE-STRUCTURE; SPECIATION; URANIUM; SEDIMENTS; CHEMISTRY; REDUCTION; AQUO AB The bonding environment of sorbed species at rock-water interfaces provides information on their mobility in natural systems. To investigate Pu sorption at a natural surface on a microscopic scale, we studied the bonding environment of sorbed Pu on zeolitic tuff with micro-XAS techniques. Using a focused 4 by 7 mu m(2) beam, XAS spectra were taken at Mn-smectite regions where high levels of sorbed Pu were found. The Pu did not sorb to Fe-rich regions. XANES spectra show the presence of Pu(VI), based on edge energy. Preliminary analyses of the micro-EXAFS spectra indicate the absence of a first shell splitting of axial and equatorial Pu-O bonds-an environment unlike what is observed for most hexavalent actinides. C1 Univ Georgia, Savannah River Ecol Lab, Aiken, SC 29802 USA. Univ Chicago, Dept Geophys Sci, Chicago, IL 60637 USA. Univ Chicago, Ctr Adv Radiat Sources, CARS, GSE, Chicago, IL 60637 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Duff, MC (reprint author), Univ Georgia, Savannah River Ecol Lab, Aiken, SC 29802 USA. NR 17 TC 15 Z9 16 U1 1 U2 6 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0909-0495 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD MAY 1 PY 1999 VL 6 BP 350 EP 352 DI 10.1107/S0909049598016811 PN 3 PG 3 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 212NA UT WOS:000081221700082 PM 15263304 ER PT J AU Rothe, J Kneedler, EM Pecher, K Tonner, BP Nealson, KH Grundl, T Meyer-Ilse, W Warwick, T AF Rothe, J Kneedler, EM Pecher, K Tonner, BP Nealson, KH Grundl, T Meyer-Ilse, W Warwick, T TI Spectromicroscopy of Mn distributions in micronodules produced by biomineralization SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 10th International Conference on XAFS (XAFS X) CY AUG 10-14, 1998 CL ILLINOIS INST TECHNOL, CHICAGO, ILLINOIS HO ILLINOIS INST TECHNOL DE soft x-ray spectromicroscopy; bacterial metabolism; Mn micronodules ID TRANSITION-METAL COMPOUNDS; OXIDATION-STATE; MANGANESE; ABSORPTION AB The interaction of single cell microorganisms with inorganic substrates is a central issue in soil and aquatic environmental chemistry. The biochemical pathways of the bacterial metabolism based on redox reactions of transition metal compounds involve the processes of microbial attachment to and subsequent modification of inorganic surfaces (biocorrosion), as well as the precipitation of inorganic compounds (biomineralization). Soft x-ray spectromicroscopy has been used to investigate Mn micronodules collected from freshwater sediments in order to attempt the direct mapping of the distribution of Mn valence states in biologically produced minerals. C1 Univ Wisconsin, Dept Phys, Milwaukee, WI 53201 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Wisconsin, Dept Geosci, Milwaukee, WI 53201 USA. EO Lawrence Berkeley Natl Lab, Ctr Xray Opt, Berkeley, CA 94720 USA. RP Rothe, J (reprint author), Univ Wisconsin, Dept Phys, POB 413, Milwaukee, WI 53201 USA. NR 10 TC 14 Z9 14 U1 0 U2 3 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0909-0495 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD MAY 1 PY 1999 VL 6 BP 359 EP 361 DI 10.1107/S0909049599001715 PN 3 PG 3 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 212NA UT WOS:000081221700085 PM 15263307 ER PT J AU Kropf, AJ Bunker, BA Furdyna, JK AF Kropf, AJ Bunker, BA Furdyna, JK TI XAFS studies of interfaces in MnSe ZnTe superlattices SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 10th International Conference on XAFS (XAFS X) CY AUG 10-14, 1998 CL ILLINOIS INST TECHNOL, CHICAGO, ILLINOIS HO ILLINOIS INST TECHNOL DE polarized XAFS; superlattice; interface ID ELECTRON YIELD; ABSORPTION AB Polarization-dependent XAFS measurements of a series of MnSe/ZnTe superlattices are presented. The results are consistent with a small interdiffusion at the interfaces, accompanied by an elastic distortion of the bond angles. This is in contrast to earlier measurements of other II-VI semiconductor superlattices. In addition, the Zn-Se bond expands by 0.027+/-0.012 Angstrom to accommodate the strain in the superlattice. C1 Univ Notre Dame, Dept Phys, Notre Dame, IN 46556 USA. RP Kropf, AJ (reprint author), Argonne Natl Lab, Div Chem Technol, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Kropf, Arthur/B-8665-2015 NR 10 TC 0 Z9 0 U1 0 U2 1 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0909-0495 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD MAY 1 PY 1999 VL 6 BP 370 EP 372 DI 10.1107/S0909049599001703 PN 3 PG 3 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 212NA UT WOS:000081221700089 PM 15263311 ER PT J AU Meyer-Klaucke, W Glaser, T Froba, M Tiemann, M Wong, J Trautwein, AX AF Meyer-Klaucke, W Glaser, T Froba, M Tiemann, M Wong, J Trautwein, AX TI Multiple K-edge XAS for the structural analysis of thiophenolate bridged heterotrinuclear complexes SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 10th International Conference on XAFS (XAFS X) CY AUG 10-14, 1998 CL ILLINOIS INST TECHNOL, CHICAGO, ILLINOIS HO ILLINOIS INST TECHNOL DE bioinorganic chemistry; multiple-edge analysis; EXAFS ID ABSORPTION AB A multiple K-edge X-ray absorption spectroscopic (XAS) approach to determine the structural parameters of an isostructural series of heterotrinuclear thiophenolate-bridged metal-complexes of the general formula [LFeCrFeL]nt (with n=1,2,3) is presented. The analysis focuses on the variation of the metal-metal distances and the metal-sulfur distances with the cluster charge n. XAS measurements on the Fe, Cr, and S-Kedges were performed to allow a fit of these distances from these constituent elements. Results show that 3 3 atoms and 3 N atoms coordinate each of the terminal Fe atoms, whereas 6 S atoms coordinate the central Cr atom. This symmetry allows extracting structural information with high accuracy especially when the spectra obtained at different edges are refined at the same time. A decrease of the metal-metal distance with increasing cluster charge is also derived from this multiple-edge analysis. C1 European Mol Biol Lab, Outstn Hamburg, D-22603 Hamburg, Germany. Max Planck Inst Strahlenchem, D-45470 Mulheim, Germany. Univ Hamburg, Inst Inorgan & Appl Chem, D-20146 Hamburg, Germany. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Univ Lubeck, Inst Phys, D-23538 Lubeck, Germany. RP Meyer-Klaucke, W (reprint author), European Mol Biol Lab, Outstn Hamburg, Notkestr 85, D-22603 Hamburg, Germany. RI Froba, Michael/B-2888-2010; Tiemann, Michael/B-1339-2008; Meyer-Klaucke, Wolfram/G-1148-2010; Glaser, Thorsten/H-5187-2013 OI Glaser, Thorsten/0000-0003-2056-7701 NR 5 TC 1 Z9 1 U1 0 U2 0 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0909-0495 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD MAY 1 PY 1999 VL 6 BP 397 EP 399 DI 10.1107/S0909049598017804 PN 3 PG 3 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 212NA UT WOS:000081221700099 PM 15263321 ER PT J AU Chen, LX Lee, PL Gosztola, D Svec, WA Wasielewski, MR AF Chen, LX Lee, PL Gosztola, D Svec, WA Wasielewski, MR TI Time-resolved energy-dispersive XAS studies of photoinduced electron transfer intermediates in electron donor-acceptor complexes SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 10th International Conference on XAFS (XAFS X) CY AUG 10-14, 1998 CL ILLINOIS INST TECHNOL, CHICAGO, ILLINOIS HO ILLINOIS INST TECHNOL DE energy dispersive XAS; photoinduced electron transfer; XANES; time-resolved XAFS; porphyrin complexes ID X-RAY-ABSORPTION; STATE; CARBOXYMYOGLOBIN; SPECTROSCOPY AB The structure around the Fe atom of a photoinduced electron transfer intermediate in a di-porphyrin electron donor/acceptor complex is studied with time-resolved energy dispersive X-ray absorption spectroscopy. Photoinduced electron transfer from the lowest excited triplet state of a Zn porphyrin attached at a fixed 25 D distance by means of a long spacer molecule to an Fe(III) porphyrin occurs with a 6 ms time constant at 77 K. Time domain X-ray absorption measurements show that Fe(III) is transiently photoreduced to Fe(II) and that the bond between the Fe atom and a pyridine molecule ligated to it weakens substantially upon reduction of the Fe. Coupling of ligand loss to reduction of Fe(III) to Fe(II) provides a mean of stabilizing the reduced intermediate. C1 Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. Argonne Natl Lab, Expt Facil Div, Argonne, IL 60439 USA. Northwestern Univ, Dept Chem, Evanston, IL 60208 USA. RP Chen, LX (reprint author), Argonne Natl Lab, Div Chem, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Gosztola, David/D-9320-2011 OI Gosztola, David/0000-0003-2674-1379 NR 16 TC 9 Z9 9 U1 0 U2 3 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0909-0495 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD MAY 1 PY 1999 VL 6 BP 403 EP 405 DI 10.1107/S0909049598014861 PN 3 PG 3 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 212NA UT WOS:000081221700101 PM 15263323 ER PT J AU Cinco, RM Robblee, JH Rompel, A Fernandez, C Sauer, K Yachandra, VK Klein, MP AF Cinco, RM Robblee, JH Rompel, A Fernandez, C Sauer, K Yachandra, VK Klein, MP TI Proximity of calcium to the manganese cluster of the photosynthetic oxygen-evolving complex determined from strontium XAFS SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 10th International Conference on XAFS (XAFS X) CY AUG 10-14, 1998 CL ILLINOIS INST TECHNOL, CHICAGO, ILLINOIS HO ILLINOIS INST TECHNOL DE manganese; EXAFS; calcium; strontium; oxygen evolution; Photosystem II ID RAY-ABSORPTION SPECTROSCOPY; PHOTOSYSTEM-II; FINE-STRUCTURE; BINDING; PLANTS AB Working on Photosystem II membranes from spinach, we substituted strontium for calcium and probed using Sr EXAFS for any nearby Mn. Sr EXAFS results indicate major differences between the functional (intact) and inactive (hydroxylamine-treated) samples. In intact samples, the Fourier transform of the Sr EXAFS shows a major peak that is missing in inactive samples. This interaction is best simulated by two Mn neighbors at a distance of similar to 3.5 Angstrom. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Phys Biosci Div, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. RP Cinco, RM (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Phys Biosci Div, Berkeley, CA 94720 USA. RI Fernandez, Carmen/C-9546-2012; Institute of Chemistry - USP, Dept. of Chemistry/B-8988-2012 OI Fernandez, Carmen/0000-0003-2201-6241; FU NIGMS NIH HHS [R01 GM055302, R56 GM055302] NR 14 TC 8 Z9 9 U1 0 U2 2 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0909-0495 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD MAY 1 PY 1999 VL 6 BP 419 EP 420 DI 10.1107/S0909049598017968 PN 3 PG 2 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 212NA UT WOS:000081221700107 PM 15263329 ER PT J AU Chen, LX Rajh, T Jager, W Nedeljkovic, J Thurnauer, MC AF Chen, LX Rajh, T Jager, W Nedeljkovic, J Thurnauer, MC TI X-ray absorption reveals surface structure of titanium dioxide nanoparticles SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 10th International Conference on XAFS (XAFS X) CY AUG 10-14, 1998 CL ILLINOIS INST TECHNOL, CHICAGO, ILLINOIS HO ILLINOIS INST TECHNOL DE XANES; XAFS; nanoparticles; titanium dioxide; semiconductor ID TI K-EDGE; SPECTROSCOPY; COORDINATION; REDUCTION; GLASSES; XANES AB The structures of TiO2 nanoparticles with a 19 Angstrom diameter have been probed using Ti K-edge XANES, revealing severe distortions in Ti site environments compared to those octahedral Ti sites in bulk anatase. The distorted Ti sites are likely to adopt a pentacoordinate square pyramid geometry due to the truncation of the lattice. Upon binding ascorbic acid on the surfaces of the 19 Angstrom particles, the octahedral Ti site observed in the bulk TiO2 is largely restored. This discovery shows that the distortions in TiO2 lattice are mainly located on the surface of the particles. The distorted Ti surface sites are responsible for the binding with other small molecules, which is often a prerequisite in surface chemistry. C1 Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. RP Chen, LX (reprint author), Argonne Natl Lab, Div Chem, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 10 TC 107 Z9 108 U1 0 U2 30 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0909-0495 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD MAY 1 PY 1999 VL 6 BP 445 EP 447 DI 10.1107/S090904959801591X PN 3 PG 3 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 212NA UT WOS:000081221700117 PM 15263339 ER PT J AU Bridges, F Cao, DL Anderson, M Booth, CH Neumeier, JJ Snyder, J AF Bridges, F Cao, DL Anderson, M Booth, CH Neumeier, JJ Snyder, J TI Temperature/magnetization-induced distortions in the local structure of substituted LaMnO3 SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 10th International Conference on XAFS (XAFS X) CY AUG 10-14, 1998 CL ILLINOIS INST TECHNOL, CHICAGO, ILLINOIS HO ILLINOIS INST TECHNOL DE CMR; XAFS; polarons ID LA1-XCAXMNO3; MANGANITES; MN; LA1-XSRXMNO3; SPECTROSCOPY; RESISTIVITY; DIFFRACTION; MAGNETISM; CHARGE AB Much of the work carried out on the Colossal Magnetoresistive (CMR) materials has been interpreted using the double exchange (DE) model which assumes Mn+3 and Mn+4 sites exist. In addition, to explain the large MR in films, it has recently been suggested that local distortions in the form of polarons, must also be present above the ferromagnetic transition temperature T-c; such distortions have now been observed. We present XAFS data which illustrate the magnitude of these distortions and show that the change in the Mn-O distortions correlates well with the magnetization. However the absorption edge is sharp and shows no structure indicative of two valence states, Mn+3 and Mn+4, in either the polaron regime or in the charge-ordered material. C1 Univ Calif Santa Cruz, Dept Phys, Santa Cruz, CA 95064 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM USA. Jet Prop Lab, Pasadena, CA 91109 USA. RP Bridges, F (reprint author), Univ Calif Santa Cruz, Dept Phys, Santa Cruz, CA 95064 USA. RI Booth, Corwin/A-7877-2008 NR 15 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 0909-0495 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD MAY 1 PY 1999 VL 6 BP 543 EP 545 DI 10.1107/S0909049598016008 PN 3 PG 3 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 212NA UT WOS:000081221700152 PM 15263374 ER PT J AU Balasubramanian, M Melendres, C AF Balasubramanian, M Melendres, C TI Local structure of chromium incorporated into electrodeposited nickel hydroxide films SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 10th International Conference on XAFS (XAFS X) CY AUG 10-14, 1998 CL ILLINOIS INST TECHNOL, CHICAGO, ILLINOIS HO ILLINOIS INST TECHNOL DE oxide films; chemical speciation; hydrous nickel oxides ID ABSORPTION FINE-STRUCTURE AB We have utilized X-ray Absorption Fine Structure (XAFS) spectroscopy to investigate the local structure of Cr (III) and Cr (VI) ions incorporated into alpha-Ni(OH)(2) films. The films were prepared by cathodic co-deposition of Cr and Ni at a constant current from aqueous solutions of nickel nitrate, chromium nitrate and potassium chromate. XAFS measurements show that in films formed from 0.1 M Ni(NO3)(2) + 0.0005 M Cr(NO3)(3), Cr (III) is incorporated into the Ni lattice sites of alpha-Ni(OH)(2). In contrast, co-deposition from a 0.1 M Ni(NO3)(2) + 0.001 M K2CrO4 solution results in Cr (VI) occupying the interlamellar sites of the brucite structure. C1 Argonne Natl Lab, Div Chem Technol, Argonne, IL 60439 USA. RP Balasubramanian, M (reprint author), Argonne Natl Lab, Div Chem Technol, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 7 TC 4 Z9 4 U1 1 U2 1 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0909-0495 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD MAY 1 PY 1999 VL 6 BP 594 EP 595 DI 10.1107/S0909049599000941 PN 3 PG 2 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 212NA UT WOS:000081221700169 PM 15263391 ER PT J AU Mansour, AN Mukerjee, S Yang, XQ McBreen, J AF Mansour, AN Mukerjee, S Yang, XQ McBreen, J TI In situ XAS of the reaction mechanism of lithium with tin-based composite oxide glass SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 10th International Conference on XAFS (XAFS X) CY AUG 10-14, 1998 CL ILLINOIS INST TECHNOL, CHICAGO, IL HO ILLINOIS INST TECHNOL DE in situ XAFS; tin-based composite oxide; structure AB We have measured the XAFS spectra of tin-based composite oxide (TCO) glass with nominal composition of Sn1.0B0.56P0.40Al0.42O3.47 during the discharge and charge cycles in an in a non-aqueous cell. Our results confirm the amorphous nature of TCO material and show that Sn in TCO is coordinated with 3 oxygen atoms at a distance of 2.12 Angstrom. Upon discharge (i.e., Li insertion), initially, Li interacts with the electrochemically active Sn-O center forming metallic Sn, most likely in the form of highly dispersed clusters, and Li2O. Upon further discharge, our results are consistent with a model in which additional Li alloys with Sn forming various alloys with composition dependent on the amount of Li inserted. The formed alloys appear to be in the form of highly dispersed clusters and/or amorphous in nature. Their local structure differs somewhat from the crystalline structure of the known Li-Sn alloys such as LiSn, Li7Sn3, or Li7Sn2. Upon charging (i.e., Li removal), metallic Sn is reversibly produced with a Sn-Sn distance intermediate to those of gray and white Sn. C1 USN, Ctr Surface Warfare, Carderock Div, Bethesda, MD 20817 USA. Brookhaven Natl Lab, Dept Appl Sci, Upton, NY 11973 USA. RP USN, Ctr Surface Warfare, Carderock Div, Code 684, Bethesda, MD 20817 USA. NR 10 TC 17 Z9 17 U1 3 U2 18 PU INT UNION CRYSTALLOGRAPHY PI CHESTER PA 2 ABBEY SQ, CHESTER, CH1 2HU, ENGLAND SN 1600-5775 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD MAY 1 PY 1999 VL 6 BP 596 EP 598 DI 10.1107/S0909049598017026 PN 3 PG 3 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 212NA UT WOS:000081221700170 PM 15263392 ER PT J AU Grolimund, D Trainor, TP Fitts, JP Kendelewicz, T Liu, P Chambers, SA Brown, GE AF Grolimund, D Trainor, TP Fitts, JP Kendelewicz, T Liu, P Chambers, SA Brown, GE TI Identification of Cr species at the aqueous solution-hematite interface after Cr(VI)-Cr(III) reduction using GI-XAFS and Cr L-edge NEXAFS SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 10th International Conference on XAFS (XAFS X) CY AUG 10-14, 1998 CL ILLINOIS INST TECHNOL, CHICAGO, ILLINOIS HO ILLINOIS INST TECHNOL DE grazing-incidence XAFS; molecular adsorption; electron transfer reaction (redox); chromium; single crystal hematite; hematite-aqueous solution interface ID ABSORPTION FINE-STRUCTURE; SURFACE; ADSORPTION; CR(III); ION AB Surface-mediated redox processes and sorption reactions occurring at the solid-liquid interface are of importance to a broad variety of environmental and industrial pollution or corrosion/passivation problems. A more fundamental understanding of the mechanisms of these reactions is required in order to increase our ability to predict interfacial phenomena. In this study, gazing-incidence XAFS (GI-XAFS) and near-edge XAFS (both L- and K-edge NEXAFS) techniques were used to investigate the chemical and structural characteristics of interfacial Cr(III) and Cr(VI) species on a molecular level. In particular, products of postulated electron transfer reactions between Cr(VI) and Fe(II) at the oxide-solution interface were investigated. Both techniques confirmed the reduction of Cr(VI) to Cr(III) mediated by a partially reduced hematite (0001) surface. The observed local structure of the interfacial chromium species emphasizes the need for an improved, molecular-level conceptualization of reactions occurring at the solid-solution interface. C1 Stanford Univ, Stanford, CA 94305 USA. SLAC, Stanford Synchrotron Radiat Lab, Stanford, CA 94309 USA. Pacific NW Natl Lab, EMSL, Richland, WA 99352 USA. RP Grolimund, D (reprint author), Stanford Univ, Stanford, CA 94305 USA. RI Fitts, Jeffrey/J-3633-2012 NR 17 TC 15 Z9 15 U1 1 U2 19 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0909-0495 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD MAY 1 PY 1999 VL 6 BP 612 EP 614 DI 10.1107/S0909049598016513 PN 3 PG 3 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 212NA UT WOS:000081221700176 PM 15263398 ER PT J AU Waychunas, G Davis, J Reitmeyer, R AF Waychunas, G Davis, J Reitmeyer, R TI GIXAFS study of Fe3+ sorption and precipitation on natural quartz surfaces SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 10th International Conference on XAFS (XAFS X) CY AUG 10-14, 1998 CL ILLINOIS INST TECHNOL, CHICAGO, IL HO ILLINOIS INST TECHNOL DE quartz surfaces; GIXAFS; sorption; Fe3+ AB Grazing-incidence EXAFS has been used to characterize the structure of Fe3+ sorbed onto natural single crystal quartz surfaces. Fe3+ sorption at ca. 5% monolayer coverage on a natural crystal allowed to equilibrate in air resulted in formation of hematite nuclei with strong texturing on r- and m-planes. EXAFS calculations suggests that both O and Fe backscattering is necessary to yield acceptable structural models, that about 50% of the sorbed iron resides in nuclei, and that the approximate dimensions of the nuclei can be estimated via Feff 7.0 calculations of various nuclei sizes and shapes. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. US Geol Survey, Div Water Resources, Menlo Pk, CA 94025 USA. RP Waychunas, G (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, 1 Cyclotron Rd, Berkeley, CA 94720 USA. EM gawaychunas@lbl.gov NR 5 TC 14 Z9 14 U1 0 U2 2 PU INT UNION CRYSTALLOGRAPHY PI CHESTER PA 2 ABBEY SQ, CHESTER, CH1 2HU, ENGLAND SN 1600-5775 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD MAY 1 PY 1999 VL 6 BP 615 EP 617 DI 10.1107/S0909049599001764 PN 3 PG 3 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 212NA UT WOS:000081221700177 PM 15263399 ER PT J AU Trainor, TP Fitts, JP Grolimund, D Bargar, JR Brown, GE AF Trainor, TP Fitts, JP Grolimund, D Bargar, JR Brown, GE TI Grazing-incidence XAFS studies of aqueous Zn(II) on sapphire single crystals SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 10th International Conference on XAFS (XAFS X) CY AUG 10-14, 1998 CL ILLINOIS INST TECHNOL, CHICAGO, ILLINOIS HO ILLINOIS INST TECHNOL DE grazing incidence XAFS; zinc; aluminum oxide ID ABSORPTION FINE-STRUCTURE AB Grazing-incidence XAFS was applied to study the sorption of Zn(II) on two crystallographically distinct surfaces of highly polished sapphire single crystals as a simplified analog for metal ion sorption on natural aluminum-(hydr)oxides. Experiments were performed both in-situ (in contact with bulk solution) and ex-situ in a humidified N-2 atmosphere. The identification of an Al shell at roughly 3 Angstrom in all samples indicates that Zn(II) binds as an inner sphere complex on both the (0001) and (1-102) surfaces. Polarization dependence of the XAFS spectra is used to propose possible sorption species. C1 Stanford Univ, GES, Stanford, CA 94305 USA. Stanford Linear Accelerator Ctr, Stanford Synchrotron Radiat Lab, Stanford, CA 94309 USA. RP Trainor, TP (reprint author), Stanford Univ, GES, Stanford, CA 94305 USA. RI Fitts, Jeffrey/J-3633-2012 NR 13 TC 4 Z9 4 U1 0 U2 3 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0909-0495 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD MAY 1 PY 1999 VL 6 BP 618 EP 620 DI 10.1107/S0909049598017038 PN 3 PG 3 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 212NA UT WOS:000081221700178 PM 15263400 ER PT J AU Doyle, CS Traina, SJ Ruppert, H Kendelewicz, T Rehr, JJ Brown, GE AF Doyle, CS Traina, SJ Ruppert, H Kendelewicz, T Rehr, JJ Brown, GE TI XANES studies at the Al K-edge of aluminium-rich surface phases in the soil environment SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 10th International Conference on XAFS (XAFS X) CY AUG 10-14, 1998 CL ILLINOIS INST TECHNOL, CHICAGO, ILLINOIS HO ILLINOIS INST TECHNOL DE Al-XANES; mineral surfaces ID MINERALS; SUBSTITUTION; ADSORPTION; GOETHITE AB Aluminum is highly abundant in the Earth's crust where it is present in a wide variety of primary and secondary aluminosilicate minerals, amorphous phases, and aqueous solution species. The speciation and coordination of Al in many of these phases, particularly those that are X-ray amorphous or present as thin surface coatings, are often unknown or based on indirect methods. We have utilized aluminum K-edge XANES in a study of the nature of several such phases, specifically the aluminum rich phases present in soils on the surfaces of quartz and feldspar grains in loess, and aluminum substitution in iron oxyhydroxides. In addition, the sorption products of Al(oxy)hydroxides on synthetic alpha-Al2O3 (0001) surfaces were investigated along with model compounds. Analysis of our data suggests that the Al-rich surface phase on quartz grains in loess is gibbsite-like, while Al sorbed on synthetic quartz is boehmite-like. Surprisingly, Al substituted in goethite appears to be more similar to gibbsite than to diaspore, which is isostructural with goethite. The experimental data for corundum and Linde alumina show good agreement with calculated Al K-edge spectra from a developmental version of the full multiple scattering code FEFF8 using clusters of up to 66 atoms. C1 Stanford Univ, Dept Geol & Environm Sci, Stanford, CA 94305 USA. Ohio State Univ, Sch Nat Resources, Columbus, OH 43210 USA. Univ Gottingen, Inst Geol & Dynam Lithosphare, D-3400 Gottingen, Germany. Univ Washington, Dept Phys, Seattle, WA 98195 USA. Stanford Linear Accelerator Ctr, Stanford Synchrotron Radiat Lab, Stanford, CA 94309 USA. RP Doyle, CS (reprint author), Stanford Univ, Dept Geol & Environm Sci, Stanford, CA 94305 USA. NR 15 TC 31 Z9 31 U1 2 U2 16 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0909-0495 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD MAY 1 PY 1999 VL 6 BP 621 EP 623 DI 10.1107/S0909049598015568 PN 3 PG 3 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 212NA UT WOS:000081221700179 PM 15263401 ER PT J AU Fitts, JP Trainor, TP Grolimund, D Bargar, JR Parks, GA Brown, GE AF Fitts, JP Trainor, TP Grolimund, D Bargar, JR Parks, GA Brown, GE TI Grazing-incidence XAFS investigations of Cu(II) sorption products at alpha-Al(2)O(3)-water and alpha-SiO(2)-water interfaces SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 10th International Conference on XAFS (XAFS X) CY AUG 10-14, 1998 CL ILLINOIS INST TECHNOL, CHICAGO, IL HO ILLINOIS INST TECHNOL DE GI-XAFS; Cu(II); sapphire; quartz ID ALPHA-ALUMINA; ADSORPTION; PB(II); CO(II) AB Grazing-Incidence XAFS was used to study the local atomic structure of Cu-containing species that form at the oxide-water interface of oriented single crystals of alpha-Al(2)O(3) and alpha-SiO(2). Cu(II) form edge-sharing bidentate complexes on both alpha-Al(2)O(3) (1-102) and (0001) surfaces, However, polarization-dependent XAFS measurements suggest that the binding sites of the surface complexes are different on the two surfaces. The distance to Si backscatterers is consistent with both monodentate and bridging bidentate Cu surface complexes on the alpha-SiO(2) (0001) surface, but the absence of structural information in the EXAFS spectra beyond similar to 3 Angstrom suggests that Cu complexes do not bond to a single well-ordered surface site. The structural information is used to explain the relative extent of Cu uptake on the three oxide surfaces studied. C1 Stanford Univ, Dept Geol & Environm Sci, Stanford, CA 94305 USA. Stanford Linear Accelerator Ctr, Stanford Synchrotron Radiat Lab, Stanford, CA 94309 USA. RP Fitts, JP (reprint author), Stanford Univ, Dept Geol & Environm Sci, Stanford, CA 94305 USA. EM fitts@pangea.stanford.edu NR 12 TC 17 Z9 17 U1 1 U2 6 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 0909-0495 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD MAY 1 PY 1999 VL 6 BP 627 EP 629 DI 10.1107/S0909049599001375 PN 3 PG 3 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 212NA UT WOS:000081221700181 PM 15263403 ER PT J AU Kemner, KM Feng, X Liu, J Fryxell, GE Wang, LQ Kim, AY Gong, M Mattigod, S AF Kemner, KM Feng, X Liu, J Fryxell, GE Wang, LQ Kim, AY Gong, M Mattigod, S TI Investigation of the local chemical interactions between Hg and self-assembled monolayers on mesoporous supports SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 10th International Conference on XAFS (XAFS X) CY AUG 10-14, 1998 CL ILLINOIS INST TECHNOL, CHICAGO, ILLINOIS HO ILLINOIS INST TECHNOL DE environmental science; separations science ID ABSORPTION FINE-STRUCTURE; MOLECULAR-SIEVES AB The synthesis of mesoporous silica has greatly expanded the possibilities for the design of open-pore structures. Because of their large surface area and well-defined pore size and pore shape, these materials have great potential in environmental and industrial processes, such as selective extraction of heavy metals from solutions. However, these applications require the materials to have specific attributes such as binding sites and charge density. Recently produced organic monolayers within ordered mesoporous silica have specific adsorption behavior for Hg and other heavy metals. This paper presents results of a study using Hg L-III edge X-ray absorption fine structure (XAFS) to understand the adsorption of Hg to this material surface. C1 Argonne Natl Lab, Div Environm Res, Argonne, IL 60439 USA. Pacific NW Natl Lab, Richland, WA 99352 USA. RP Kemner, KM (reprint author), Argonne Natl Lab, Div Environm Res, Argonne, IL 60439 USA. RI ID, MRCAT/G-7586-2011 NR 11 TC 30 Z9 30 U1 0 U2 1 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0909-0495 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD MAY 1 PY 1999 VL 6 BP 633 EP 635 DI 10.1107/S090904959801560X PN 3 PG 3 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 212NA UT WOS:000081221700183 PM 15263405 ER PT J AU Kemner, KM Yun, W Cai, Z Lai, B Lee, HR Maser, J Legnini, DG Rodrigues, W Jastrow, JD Miller, RM Pratt, ST Schneegurt, MA Kulpa, CF AF Kemner, KM Yun, W Cai, Z Lai, B Lee, HR Maser, J Legnini, DG Rodrigues, W Jastrow, JD Miller, RM Pratt, ST Schneegurt, MA Kulpa, CF TI Using zone plates for X-ray microimaging and microspectroscopy in environmental science SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 10th International Conference on XAFS (XAFS X) CY AUG 10-14, 1998 CL ILLINOIS INST TECHNOL, CHICAGO, ILLINOIS HO ILLINOIS INST TECHNOL DE zone plates; environmental science; X-ray microbeams; X-ray imaging; biogeochemistry AB Understanding the transport and ultimate fate of environmental contaminants is of fundamental importance for developing effective remediation strategies and determining the risk associated with the contaminants. Focusing X-rays by using recently developed zone plates allows determination of the spatial distribution and chemical speciation of contaminants at the micron and submicron length scales. This ability is essential for studying the microscopic physical, geological, chemical, and biological interfaces that play a crucial role in determining contaminant fate and mobility. The following is an overview of some current problems in environmental science that are being addressed with synchrotron-based X-ray microimaging and microspectroscopy. C1 Argonne Natl Lab, Argonne, IL 60439 USA. Univ Notre Dame, Dept Biol Sci, Notre Dame, IN 46556 USA. RP Kemner, KM (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Maser, Jorg/K-6817-2013 NR 7 TC 10 Z9 10 U1 0 U2 1 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0909-0495 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD MAY 1 PY 1999 VL 6 BP 639 EP 641 DI 10.1107/S0909049598016586 PN 3 PG 3 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 212NA UT WOS:000081221700185 PM 15263407 ER PT J AU Templeton, AS Ostergren, JD Trainor, TP Foster, AL Traina, SJ Spormann, A Brown, GE AF Templeton, AS Ostergren, JD Trainor, TP Foster, AL Traina, SJ Spormann, A Brown, GE TI XAFS and XSW study of the distribution of Pb(II) sorbed to biofilms on alpha-Al2O3 and alpha-FeOOH surfaces SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 10th International Conference on XAFS (XAFS X) CY AUG 10-14, 1998 CL ILLINOIS INST TECHNOL, CHICAGO, IL HO ILLINOIS INST TECHNOL DE biofilm; Pb(II); XSW; alumina; goethite ID BOND-VALENCE DETERMINATION; OXIDE-WATER INTERFACES; EXAFS SPECTROSCOPY; SORPTION PRODUCTS; COMPLEXATION; MONONUCLEAR; SITES AB Biofilms form ubiquitous organic coatings surfaces in soil and aquatic environments. In order to understand the chemical speciation of heavy metals (such as Pb) sorbed to minerals colonized by bacteria, it is essential to evaluate the coupled biotic and abiotic sorption by such heterogeneous systems. We have used EXAFS spectroscopy to quantitatively determine the partitioning of Pb between biofilms (Burkholderia cepacia) and the reactive sites on powdered alpha-Al2O3 and alpha-FeOOH. We have also used x-ray standing wave (XSW) methods to study the distribution of Pb sorbed to biofilms grown on the surface of single crystal alpha-Al2O3 (1-102). The XSW data show that Pb occurs dominantly at the alpha-Al2O3 (1-102) surface at low [Pb](T), and is more distributed within the biofilm at higher [Pb](T). The Pb L-III EXAFS data show that Pb is partitioned more strongly to the alpha-FeOOH surface than the alpha-Al2O3 surface relative to the biofilm. However, the fraction of Pb sorbed to the alpha-Al2O3 mineral surface relative to the biofilm may increase as Pb coverage increases. C1 Stanford Univ, Stanford, CA 94305 USA. Ohio State Univ, Sch Nat Resources, Columbus, OH 43210 USA. Stanford Linear Accelerator Ctr, Stanford Synchrotron Radiat Lab, Stanford, CA 94309 USA. RP Templeton, AS (reprint author), Stanford Univ, Stanford, CA 94305 USA. EM alexis@pangea.stanford.edu OI TEMPLETON, ALEXIS/0000-0002-9670-0647 NR 13 TC 10 Z9 10 U1 1 U2 10 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 0909-0495 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD MAY 1 PY 1999 VL 6 BP 642 EP 644 DI 10.1107/S0909049598017798 PN 3 PG 3 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 212NA UT WOS:000081221700186 PM 15263408 ER PT J AU Ostergren, JD Bargar, JR Brown, GE Parks, GA AF Ostergren, JD Bargar, JR Brown, GE Parks, GA TI Combined EXAFS and FTIR investigation of sulfate and carbonate effects on Pb(II) sorption to goethite (alpha-FeOOH) SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 10th International Conference on XAFS (XAFS X) CY AUG 10-14, 1998 CL ILLINOIS INST TECHNOL, CHICAGO, IL HO ILLINOIS INST TECHNOL DE Pb; sulfate; carbonate; sorption; goethite ID SURFACE COMPLEXATION; ADSORPTION; HEMATITE; OXIDE AB Understanding the effects of carbonate and sulfate on Pb(II) sorption to iron (hydr)oxides is critically important in developing accurate models of Pb fate and transport in natural environments. Macroscopic measurements show that Pb(II) uptake on iron (hydr)oxides can be altered significantly by dissolved sulfate and carbonate. Our investigation elucidates the molecular-scale processes giving rise to these macroscopic effects by characterizing the structures of Pb(II) sorption complexes forming on goethite (alpha-FeOOH) in the presence of carbonate and, in separate experiments, sulfate using in-situ Pb L(III)-EXAFS and ATR-FTIR spectroscopies. Under all conditions studied, Pb(II) forms predominantly bidentate inner-sphere complexes to Fe(O,OH)(6) octahedra. Both corner- and edge-sharing complexes are observed by EXAFS spectroscopy. The relative fraction of corner-sharing complexes increases at low pH (5-6) for carbonate concentrations up to 1 atm (i.e., we see the same behavior in samples free of added ligands and in those with carbonate present up to 1 atm), and is enhanced in the presence of sulfate. The formation of ternary surface complexes is evaluated as a possible explanation for enhanced Pb uptake in the presence of high CO(2) (1 atm) and in the presence of sulfate. C1 Stanford Univ, Dept Geol & Environm Sci, Stanford, CA 94305 USA. Stanford Linear Accelerator Ctr, Stanford Synchrotron Radiat Lab, Stanford, CA 94309 USA. RP Ostergren, JD (reprint author), Stanford Univ, Dept Geol & Environm Sci, Stanford, CA 94305 USA. EM johno@pangea.stanford.edu NR 17 TC 13 Z9 13 U1 2 U2 14 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 0909-0495 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD MAY 1 PY 1999 VL 6 BP 645 EP 647 DI 10.1107/S0909049598017750 PN 3 PG 3 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 212NA UT WOS:000081221700187 PM 15263409 ER PT J AU Berrodier, I Farges, F Benedetti, M Brown, G AF Berrodier, I Farges, F Benedetti, M Brown, G TI Adsorption of Au ferrihydrites using Au-L-III edge XAFS spectroscopy SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 10th International Conference on XAFS (XAFS X) CY AUG 10-14, 1998 CL ILLINOIS INST TECHNOL, CHICAGO, IL HO ILLINOIS INST TECHNOL DE gold; iron; adsorption; ferrihydrites; XAFS AB Samples of Au(III) adsorbed onto ferrihydrites have been prepared from pure ferrihydrites and various gold(III) chloride solutions and characterized by Au-L-III edge XAFS spectroscopy. On ferrihydrite surfaces, Au;is present either as Au(III)Cl2O23- or ALI(III)ClO34-, Au(III)O-4(5-) square planar complexes with Au-O and Au-Cl distances of 2.00(2) and 2.28(2) Angstrom. These results show that the redox state of Au remains unchanged during adsorption in contrast to the short range environment of Au which is strongly sensitive on the pH and the Cl molality of the solution during adsorption. C1 Univ Marne la Vallee, Lab Geomat, F-77454 Marne La Vallee 2, France. ENSMP, F-77454 Marne La Vallee 2, France. Univ Paris 06, ESA CNRS 7047, F-75251 Paris 05, France. Stanford Univ, Dept Geol, Stanford, CA 94305 USA. Stanford Univ, SSRL, Stanford, CA 94305 USA. RP Berrodier, I (reprint author), Univ Marne la Vallee, Lab Geomat, F-77454 Marne La Vallee 2, France. EM berrodie@univ-mlv.fr RI Benedetti, Marc/A-5463-2011 OI Benedetti, Marc/0000-0003-1075-8205 NR 6 TC 10 Z9 10 U1 0 U2 3 PU INT UNION CRYSTALLOGRAPHY PI CHESTER PA 2 ABBEY SQ, CHESTER, CH1 2HU, ENGLAND SN 1600-5775 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD MAY 1 PY 1999 VL 6 BP 651 EP 652 DI 10.1107/S0909049598017841 PN 3 PG 2 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 212NA UT WOS:000081221700189 PM 15263411 ER PT J AU Ressler, T Wong, J Roos, J AF Ressler, T Wong, J Roos, J TI Manganese speciation in exhaust particulates of automobiles using MMT-containing gasoline SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 10th International Conference on XAFS (XAFS X) CY AUG 10-14, 1998 CL ILLINOIS INST TECHNOL, CHICAGO, ILLINOIS HO ILLINOIS INST TECHNOL DE Mn speciation; MMT-gasoline; exhaust particulates AB XAFS spectroscopy is used to speciate Mn-containing auto exhaust particulates emitted from MMT-added gasoline engines and collected in a controlled manner. A series of Mn compounds was also measured to model and aid quantification of the unknown species in the particulates. XANES results show that the average Mn valence in these particulates is similar to 2.2 and that MnO, Mn3O4, MnSO4. H2O and a Mn phosphate are the predominant phases present. The amount of each component varies depending on engine history and test cycle. The XAFS analysis was found to corroborate the XANES results. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Ethyl Co, Richmond, VA 23216 USA. RP Ressler, T (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808, Livermore, CA 94551 USA. NR 5 TC 58 Z9 59 U1 1 U2 2 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0909-0495 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD MAY 1 PY 1999 VL 6 BP 656 EP 658 DI 10.1107/S0909049598015623 PN 3 PG 3 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 212NA UT WOS:000081221700191 PM 15263413 ER PT J AU Cao, DL Bridges, F Booth, C Worledge, D AF Cao, DL Bridges, F Booth, C Worledge, D TI The effect of the annealing temperature on the local distortion of La0.67Ca0.33MnO3 thin films SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 10th International Conference on XAFS (XAFS X) CY AUG 10-14, 1998 CL ILLINOIS INST TECHNOL, CHICAGO, ILLINOIS HO ILLINOIS INST TECHNOL DE XAFS; thin film; CMR ID LA1-XCAXMNO3; MAGNETISM AB The colossal magnetoresistance (MR) of the La1-xCaxMnO3 system has been studied extensively. From our previous studies, we find there is an important connection between local distortions and magnetism in these materials. Recently, we have carried out Mn K-edge fluorescence experiments with thin film samples (3000 Angstrom) of La0.67Ca0.33MnO3: one is as-deposited; another one is post-annealed at 1200 K. We find that the local distortion decreases with increasing the annealing temperature. For measurements as a function of temperature, the change of the local distortion is largest for the 1200 K annealed sample. The small change for the as-deposited sample, which has the highest MR, indicates that another mechanism contributes. C1 Univ Calif Santa Cruz, Dept Phys, Santa Cruz, CA 95064 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Stanford Univ, Dept Appl Phys, Stanford, CA 94305 USA. RP Cao, DL (reprint author), Univ Calif Santa Cruz, Dept Phys, Santa Cruz, CA 95064 USA. RI Booth, Corwin/A-7877-2008 NR 9 TC 0 Z9 0 U1 0 U2 0 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0909-0495 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD MAY 1 PY 1999 VL 6 BP 682 EP 684 DI 10.1107/S0909049599000953 PN 3 PG 3 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 212NA UT WOS:000081221700200 PM 15263422 ER PT J AU Ressler, T Brock, SL Wong, J Suib, SL AF Ressler, T Brock, SL Wong, J Suib, SL TI Structural studies on colloidal tetraalkylammonium manganese oxides SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 10th International Conference on XAFS (XAFS X) CY AUG 10-14, 1998 CL ILLINOIS INST TECHNOL, CHICAGO, ILLINOIS HO ILLINOIS INST TECHNOL DE XAFS; FEFF; multiple scattering; focusing effect; colloids ID HYDROUS OXIDES; SPECTROSCOPY; INFORMATION; CHEMISTRY; MN; FE; CO; NI AB XAFS at the Mn K edge was employed to elucidate the structure of colloidal tetraalkylammonium (TAA) manganese oxides in sols and gels obtained by different preparation and heat treatment procedures. XANES analysis revealed an average valence of similar to 3.7 for as-synthesized TAA colloids, whereas gelled TAA colloids showed a decreased average valence of similar to 3.5. XAFS analysis was carried out to distances of similar to 6.0 Angstrom around the central Mn atom employing theoretical backscattering phases and amplitudes calculated with the abinitio code FEFF. A Birnessite layer MnOx model structure was used which resulted in a good agreement with experimental data. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Univ Connecticut, Dept Chem, Storrs, CT 06269 USA. RP Ressler, T (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808, Livermore, CA 94551 USA. NR 8 TC 12 Z9 14 U1 0 U2 6 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0909-0495 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD MAY 1 PY 1999 VL 6 BP 728 EP 730 DI 10.1107/S0909049599001065 PN 3 PG 3 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 212NA UT WOS:000081221700217 PM 15263439 ER PT J AU Haskel, D Stern, EA Dogan, F Moodenbaugh, AR AF Haskel, D Stern, EA Dogan, F Moodenbaugh, AR TI Structural disorder and the origin of high-T-c suppression in La1.875Ba0.125CuO4 SO JOURNAL OF SYNCHROTRON RADIATION LA English DT Article; Proceedings Paper CT 10th International Conference on XAFS (XAFS X) CY AUG 10-14, 1998 CL ILLINOIS INST TECHNOL, CHICAGO, ILLINOIS HO ILLINOIS INST TECHNOL DE superconductivity; barium doping; mobility gap ID PHASE-TRANSITIONS; SUPERCONDUCTIVITY; LA2-XBAXCUO4; MECHANISM; SPINS; HOLES AB Polarized x-ray absorption fine structure (XAFS) measurements at all La, Pa and Cu sites were used to study local structural features that accompany the strong T-c suppression at x similar to 1/8 in La2-xBaxCuO4. Two critical parameters regulating the strength of hole-lattice coupling in this material were determined, i.e., the direction and magnitude of CuO6 octahedra local tilts. Our findings include the existence of large disorder in the magnitude of the tilt angle about its average value [theta], with an rms root[delta theta(2)] approximate to 2[theta]. We suggest that this large disorder strongly scatters a large fraction of states at the Fermi surface for x similar to 1/8 leading to the observed T-c suppression. C1 Univ Washington, Dept Phys, Seattle, WA 98195 USA. Univ Washington, Dept Mat Sci & Engn, Seattle, WA 98195 USA. Brookhaven Natl Lab, Div Mat Sci, Upton, NY 11973 USA. RP Haskel, D (reprint author), Univ Washington, Dept Phys, Seattle, WA 98195 USA. NR 12 TC 1 Z9 1 U1 0 U2 0 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0909-0495 J9 J SYNCHROTRON RADIAT JI J. Synchrot. Radiat. PD MAY 1 PY 1999 VL 6 BP 755 EP 757 DI 10.1107/S0909049599001478 PN 3 PG 3 WC Instruments & Instrumentation; Optics; Physics, Applied SC Instruments & Instrumentation; Optics; Physics GA 212NA UT WOS:000081221700226 PM 15263448 ER PT J AU Norton, SJ AF Norton, SJ TI Fluid flow imaging by means of wide-band diffraction tomography SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article AB The problem of reconstructing a two-dimensional distribution of fluid flow from wide-band scattering measurements is considered. Reciprocal scattering measurements are employed, meaning that scattered waves are recorded between a source and receiver, and again with the source and receiver interchanged. As shown, such measurements allow the reconstruction of a fluid flow image separate from that of a distribution of stationary acoustic velocity inhomogeneities. [S0001-4966(99)00105-8]. C1 Geophex Ltd, Raleigh, NC 27603 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Norton, SJ (reprint author), Geophex Ltd, 605 Mercury St, Raleigh, NC 27603 USA. NR 8 TC 8 Z9 8 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0001-4966 J9 J ACOUST SOC AM JI J. Acoust. Soc. Am. PD MAY PY 1999 VL 105 IS 5 BP 2717 EP 2721 DI 10.1121/1.426889 PG 5 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA 196LQ UT WOS:000080310200020 PM 10335623 ER PT J AU Pierson, WR Schorran, DE Fujita, EM Sagebiel, JC Lawson, DR Tanner, RL AF Pierson, WR Schorran, DE Fujita, EM Sagebiel, JC Lawson, DR Tanner, RL TI Assessment of nontailpipe hydrocarbon emissions from motor vehicles SO JOURNAL OF THE AIR & WASTE MANAGEMENT ASSOCIATION LA English DT Article ID VOLATILE ORGANIC-COMPOUNDS; TUSCARORA MOUNTAIN TUNNELS; CHEMICAL MASS-BALANCE; SOURCE-RECONCILIATION; ATMOSPHERIC HYDROCARBONS; RECEPTOR MODEL; FORT MCHENRY; AIR-QUALITY; INVENTORY; VALIDATION AB This report evaluates tailpipe and nontailpipe hydrocarbon (HC) emissions from light-duty spark-ignition (SI) vehicles. The sources of information were unpublished data sets, generated mainly from 1990 through 1994, on emissions from volunteer fleets of in-use vehicles in chassis dynamometer and sealed housing for evaporative determination tests, and published chemical mass balance (CMB) source apportionments of HC in roadway tunnels and in urban air. The nontailpipe emissions evaluated comprise running-loss, hot soak, diurnal emissions, and resting-loss emissions. Relations between pressure and purge test failures and actual nontailpipe emissions were also examined. According to the recruited fleet data, nontailpipe emissions exceed tailpipe HC emissions by a wide margin. This is contradicted by real-world ambient and roadway tunnel CMB results, which attribute 65-93% of motor vehicle non-methane hydrocarbons (NMHCs) to tailpipe emissions, and the balance from the nontailpipe. Running-loss emission rates were critically dependent on driving cycle and conditioning. They decreased steeply with increasing vehicle speed, according to the fleet data. They increased with ambient temperature and fuel Reid vapor pressure (RVP) at rates of similar to 7%/degrees F and 46%/psi. Hot soak, diurnal, and resting-loss emission rates all increased with increasing ambient temperatures, at rates in the range of 2.2-4.6%/degrees F. Hot soak and diurnal emission rates increased with increasing fuel RVP, at rates between 34 and 47%/psi increase in RVP (at 95 degrees F ambient temperature). Vehicle-to-vehicle variation in HC emission rates was very large in all nontailpipe (and tailpipe) emissions categories. For each emission category 10% of the vehicles produced similar to 50% of the emissions. The dirtiest 10% of the vehicles in any one category, however, were not usually the same vehicles as the dirtiest 10% of the vehicles in any other category; the emission rates in any one category were uncorrelated with the emission rates in any other category. High emissions in every category-tailpipe, running loss, hot soak, diurnal, and resting loss-were seen in nearly all model years, including the newest ones, There appears to be a slow (similar to 10-15%/model year) downward trend in average hot soak, diurnal, and resting-loss emissions in successive model years (whether because of improving technology or because of vehicle age-or both-is not known). There was little relation of pressure or purge failure to actual hot soak, diurnal, or resting-loss emissions rates. The paper concludes with recommendations for resolving the two outstanding issues of (1) fleet versus tunnel/ambient and (2) running losses. C1 Univ Nevada, Desert Res Inst, Reno, NV 89506 USA. Natl Renewable Energy Lab, Golden, CO 80401 USA. TVA Environm Res Ctr, Muscle Shoals, AL 35662 USA. RP Pierson, WR (reprint author), Univ Nevada, Desert Res Inst, POB 60220, Reno, NV 89506 USA. NR 95 TC 18 Z9 18 U1 0 U2 9 PU AIR & WASTE MANAGEMENT ASSOC PI PITTSBURGH PA ONE GATEWAY CENTER, THIRD FL, PITTSBURGH, PA 15222 USA SN 1047-3289 J9 J AIR WASTE MANAGE JI J. Air Waste Manage. Assoc. PD MAY PY 1999 VL 49 IS 5 BP 498 EP 519 PG 22 WC Engineering, Environmental; Environmental Sciences; Meteorology & Atmospheric Sciences SC Engineering; Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA 194YN UT WOS:000080222500001 PM 28072305 ER PT J AU Lindberg, SE Price, JL AF Lindberg, SE Price, JL TI Airborne emissions of mercury from municipal landfill operations: A short-term measurement study in Florida SO JOURNAL OF THE AIR & WASTE MANAGEMENT ASSOCIATION LA English DT Article ID EXCHANGE; PLANT; TESTS; VAPOR; SOILS AB Large quantities of mercury (Hg) have been placed in municipal landfills from a wide array of sources, including fluorescent lights, batteries, electrical switches, thermometers, and general waste. Despite its known volatility, persistence, and toxicity in the environment, the fate of this Hg has not been widely studied. Using automated flux chambers and atmospheric sampling, we quantified the primary pathways of Hg vapor releases to the atmosphere at two municipal landfill operations in south Florida for eight days in April 1997. These pathways included landfill gas (LFG) releases from passive and active vent systems, passive emissions from landfill surface covers of different ages (including CH4 "hot spots"), and emissions from daily activities at a working face (WF). Hg vapor was released to the atmosphere at readily detectable rates from all sources measured. Emission rates ranged from similar to 1 to 20 ng m(-2) hr(-1) over aged surface covers (generally comparable to background soils), from similar to 6 to 2400 ng/hr from LFG vents and flares, and from similar to 5 to 60 mg/hr at the WF. In general the fluxes increased from older to newer landfills, from fresh to aged cover, and from passive to active venting systems. Limited data suggest that methyl- and other organo-mercury compounds may also be emitted from these sites, suggesting an important area for future research. We estimate that atmospheric Hg releases from municipal landfill operations in the state of Florida are on the order of 10 kg/yr, or <1% of the estimated total anthropogenic Hg releases to air in this region. C1 Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. Florida Dept Environm Protect, Waste Management Div, Tallahassee, FL USA. RP Lindberg, SE (reprint author), Oak Ridge Natl Lab, Div Environm Sci, POB 2008, Oak Ridge, TN 37831 USA. NR 29 TC 53 Z9 60 U1 3 U2 8 PU AIR & WASTE MANAGEMENT ASSOC PI PITTSBURGH PA ONE GATEWAY CENTER, THIRD FL, PITTSBURGH, PA 15222 USA SN 1047-3289 J9 J AIR WASTE MANAGE JI J. Air Waste Manage. Assoc. PD MAY PY 1999 VL 49 IS 5 BP 520 EP 532 PG 13 WC Engineering, Environmental; Environmental Sciences; Meteorology & Atmospheric Sciences SC Engineering; Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA 194YN UT WOS:000080222500002 PM 28072307 ER PT J AU Moorhead, AJ Kim, HE AF Moorhead, AJ Kim, HE TI Strength and magnetic properties of a laminated composite of magnetic metal foil and zirconia SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article AB A layered composite material composed of magnetic metal foil and ZrO2 was fabricated by hot-pressing. The interfacial strength between the metal and the ceramic increased with hot-pressing temperature up to 1250 degrees C, and decreased thereafter because of excessive reactions at the interface. The maximum interfacial fracture strength obtained was 420 MPa. Reasonably good magnetic properties, i.e., permeabilities greater than 2000 and ac core losses less than 100 W/kg, were obtained from these specimens. Magnetic core materials fabricated in this process can thus be used under severe conditions such as high temperature and high speed rotation with little dimensional tolerance. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. Seoul Natl Univ, Sch Mat Sci & Engn, Ctr Microstruct Sci Mat, Seoul 151742, South Korea. RP Moorhead, AJ (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, POB 2008, Oak Ridge, TN 37831 USA. NR 8 TC 3 Z9 3 U1 0 U2 2 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43081-6136 USA SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD MAY PY 1999 VL 82 IS 5 BP 1349 EP 1351 PG 3 WC Materials Science, Ceramics SC Materials Science GA 198WU UT WOS:000080447900040 ER PT J AU Walker, TH Cochran, HD Hulbert, GJ AF Walker, TH Cochran, HD Hulbert, GJ TI Supercritical carbon dioxide extraction of lipids from Pythium irregulare SO JOURNAL OF THE AMERICAN OIL CHEMISTS SOCIETY LA English DT Article DE extraction kinetics; fungi; phase equilibria; polyunsaturated fatty acids; Pythium irregulare; supercritical fluid extraction; supercritical carbon dioxide; surfactant ID FLUID EXTRACTION; CO2 EXTRACTION; FATTY-ACIDS; OIL; MICROEMULSIONS; EQUILIBRIUM; SOLUBILITY; WATER AB Lipids that contain polyunsaturated fatty acids (PUFA) have therapeutic value. PUFA, however, degrade in high-temperature, oxygen-rich conditions typical of conventional hat solvent-extraction and distillation methods. Supercritical CO2 extraction was chosen as an alternative method to recover these valuable compounds from the lower fungus, Pythium irregulare. Freeze-dried biomass was subjected to an aqueous phase and placed into a flow-through extraction apparatus. Extraction of oil from this biomass showed some success for moisture contents as high as 30% (wet basis). The addition of a novel CO2-philic surfactant to the wet biomass with moisture contents as high as 95% (wet basis) increased the extraction rate of fungal oil by more than an order of magnitude. For tests with extraction times of 5 to 6 h, data for the diffusion-controlled region were modeled with an analytical solution to Fick's second law. Equilibrium data were also obtained for the fungal oil at two isotherms (40 and 60 degrees C) over a pressure range of 13.7 to 27.5 MPa. C1 Louisiana State Univ, Dept Biol & Agr Engn, Baton Rouge, LA 70803 USA. Oak Ridge Natl Lab, Div Chem Technol, Oak Ridge, TN 37831 USA. Univ Tennessee, Dept Food Sci & Technol, Knoxville, TN 37901 USA. RP Walker, TH (reprint author), Louisiana State Univ, Dept Biol & Agr Engn, 149 EB Doran Bldg, Baton Rouge, LA 70803 USA. RI Walker, Terry/A-2029-2016 OI Walker, Terry/0000-0002-3701-6386 NR 41 TC 24 Z9 25 U1 2 U2 8 PU AMER OIL CHEMISTS SOC A O C S PRESS PI CHAMPAIGN PA 1608 BROADMOOR DRIVE, CHAMPAIGN, IL 61821-0489 USA SN 0003-021X J9 J AM OIL CHEM SOC JI J. Am. Oil Chem. Soc. PD MAY PY 1999 VL 76 IS 5 BP 595 EP 602 DI 10.1007/s11746-999-0009-3 PG 8 WC Chemistry, Applied; Food Science & Technology SC Chemistry; Food Science & Technology GA 199FT UT WOS:000080470500009 ER PT J AU Leskovar, DI Esensee, V Belefant-Miller, H AF Leskovar, DI Esensee, V Belefant-Miller, H TI Pericarp, leachate, and carbohydrate involvement in thermoinhibition of germinating spinach seeds SO JOURNAL OF THE AMERICAN SOCIETY FOR HORTICULTURAL SCIENCE LA English DT Article DE Spinacia oleracea; ABA; abscisic acid; alternating temperatures; dormancy; embryo; oligosaccharide; seedcoat ID HIGH-TEMPERATURE; ABSCISIC-ACID; SCARIFICATION AB Spinach (Spinacia oleracea L.) seed germination can be inhibited by high temperatures. An understanding of thermoinhibition in spinach is critical in predicting germination and emergence events. The purpose of this study was 3-fold: 1) to determine seed germination percentage and rate of spinach genotypes-'Casscade, 'ACX 5044', 'Fall Green', and 'ARK 88-354'-exposed to constant and alternating temperatures; 2) to determine the nature and extent of inhibition imposed by the pericarp; and 3) to investigate leachate and oligosaccharide involvement in thermoinhibition. Germination inhibition began at >20 degrees C constant temperature and was totally suppressed at 35 degrees C. Alternating temperatures at 30/15 degrees C (12-hour day/12-hour night) resulted in greater germination than a constant 30 degrees C. The genotype sensitivity to supraoptimal temperatures was in the order of 'ARK 88-354' less than or equal to 'Fall Green' < 'ACX 5044' < 'Cascade', but the highly thermoinhibited 'Cascade' seeds retained the ability to germinate when shifted to lower incubation temperatures. The pericarp inhibited germination, since seeds deprived of the pericarp had approximate to 90% germination at 30 degrees C. 'ACX 5044' and 'Cascade' had higher ABA content in the pericarp than 'ARK 88-354' and 'Fall Green'. Before imbibition at 30 degrees C, raffinose levels in each genotype were in the order of 'ARK 88-354' > 'Fall Green' > 'Cascade'. After 48 hours of imbibition, sucrose and glucose levels were highest and raffinose levels were lowest in 'ARK 88-354' and 'Fall Green' seeds, while 'Cascade' seeds remained less active metabolically. These data suggest that the pericarp apparently acts as thermoinhibition. C1 Texas A&M Univ, Dept Hort Sci, Texas Agr Expt Stn, Uvalde, TX 78801 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Leskovar, DI (reprint author), Texas A&M Univ, Dept Hort Sci, Texas Agr Expt Stn, 1619 Garner Field Rd, Uvalde, TX 78801 USA. NR 20 TC 13 Z9 13 U1 0 U2 7 PU AMER SOC HORTICULTURAL SCIENCE PI ALEXANDRIA PA 113 S WEST ST, STE 200, ALEXANDRIA, VA 22314-2851 USA SN 0003-1062 J9 J AM SOC HORTIC SCI JI J. Am. Soc. Hortic. Sci. PD MAY PY 1999 VL 124 IS 3 BP 301 EP 306 PG 6 WC Horticulture SC Agriculture GA 184UQ UT WOS:000079632500015 ER PT J AU Grgur, BN Markovic, NM Ross, PN AF Grgur, BN Markovic, NM Ross, PN TI The electro-oxidation of H-2 and H-2/CO mixtures on carbon-supported PtxMoy alloy catalysts SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID ROTATING-DISK ELECTRODE; PT-RU; CO ELECTROOXIDATION; SURFACE AB Electro-oxidation kinetics of H-2 and H-2/CO mixture were studied on bimetallic Pt-Mo catalysts supported on a high-surface-area carbon black. The Pt:Mo atomic ratios in the catalysts were 3:1 and 4:1. Characterization of these catalysts by X-ray diffraction indicated the existence of a face-centered cubic metallic phase with an average particle size of ca. 4 nm. Because the lattice constants for the Pt-Mo solid solutions are so close to those of pure Pt, the composition of the nanocrystalline phase, could not be determined. The kinetic results with the supported catalysts were compared quantitatively with results from bulk alloy electrodes having well-characterized surface compositions varying from 15 to 33 atom % Mo. The kinetic properties of the supported catalysts were comparable to those of bulk alloys having somewhat higher Mo concentrations than the atomic ratios in the catalysts. This suggests that either the surface segregation phenomena in the alloy nanocrystals are different from those in the bulk or that the alloying by Pt is incomplete, and the alloy nanocrystals are rich in Mo relative to the atomic ratios in the catalysts. We prefer the latter interpretation. These Pt-Mo alloy catalysts are predicted to have significantly better "CO tolerance" in polymer electrolyte membrane fuel cells than Pt-Ru alloy catalyts, consistent with previous predictions based on studies of bulk alloy electrodes. (C) 1999 The Electrochemical Society. S0013-4651(98)07-023-2. All rights reserved. C1 Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Sci Mat, Berkeley, CA 94720 USA. RP Grgur, BN (reprint author), Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Sci Mat, Berkeley, CA 94720 USA. OI Grgur, Branimir/0000-0003-4684-9053 NR 18 TC 141 Z9 144 U1 1 U2 13 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 65 SOUTH MAIN STREET, PENNINGTON, NJ 08534 USA SN 0013-4651 J9 J ELECTROCHEM SOC JI J. Electrochem. Soc. PD MAY PY 1999 VL 146 IS 5 BP 1613 EP 1619 DI 10.1149/1.1391815 PG 7 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA 197AW UT WOS:000080343300001 ER PT J AU Boyle, TJ Ingersoll, D Rodriguez, MA Tafoya, CJ Doughty, DH AF Boyle, TJ Ingersoll, D Rodriguez, MA Tafoya, CJ Doughty, DH TI An alternative lithium cathode material: Synthesis, characterization, and electrochemical analysis of Li-8(Ni5Co2Mn)O-16 SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID LICOO2 THIN-FILMS; SYSTEM CO-LI2CO3; ION BATTERIES; PERFORMANCE; ELECTRODE; OXIDES; CELLS; ROUTE; PROSPECTS; BEHAVIOR AB We have previously reported a nonaqueous solution route to LiMn2O4 and LiCoO2 materials that have demonstrated acceptable characteristics for use as lithium battery cathode materials. Due to the flexibility of our processes, complex formulations of cathode materials can be easily generated and studied. Utilizing this flexibility, we have investigated a complex lithium transition metal oxide material, Li-8(Ni5Co2Mn)O-16, far use as an alternative cathode material. This material was analyzed by X-ray diffraction and scanning electron microscopy techniques which indicated it was phase pure. Electrochemical investigations revealed a high capacity (similar to 150 mAh/g) with a fade rate of similar to 0.41 mAh/g/cycle (0.27%/cycle). (C) 1999 The Electrochemical Society. S0013-4651(98)09-051-X. All rights reserved. C1 Sandia Natl Labs, Adv Mat Lab, Albuquerque, NM 87106 USA. Sandia Natl Labs, Lithium Battery Res & Dev Dept, Albuquerque, NM 87185 USA. X Ray Anal, Albuquerque, NM 87185 USA. RP Boyle, TJ (reprint author), Sandia Natl Labs, Adv Mat Lab, POB 5800, Albuquerque, NM 87106 USA. NR 50 TC 15 Z9 15 U1 1 U2 5 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 65 SOUTH MAIN STREET, PENNINGTON, NJ 08534 USA SN 0013-4651 J9 J ELECTROCHEM SOC JI J. Electrochem. Soc. PD MAY PY 1999 VL 146 IS 5 BP 1683 EP 1686 DI 10.1149/1.1391826 PG 4 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA 197AW UT WOS:000080343300012 ER PT J AU Haight, SM Schwartz, DT Lilga, MA AF Haight, SM Schwartz, DT Lilga, MA TI In situ oxidation state profiling of nickel hexacyanoferrate derivatized electrodes using line-imaging Raman spectroscopy and multivariate calibration SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID PRINCIPAL COMPONENT ANALYSIS; THIN-FILMS; ION SELECTIVITY; PRUSSIAN BLUE; SURFACES; INTERFACE; TRANSPORT; COMPLEXES; DENSITY; PROBE AB Reported is the use of line-imaging Raman spectroscopy for the in situ determination of oxidation state profiles in nickel hexacyanoferrate derivatized electrodes under potential control in an electrochemical cell. Line-imaging Raman spectroscopy is used to collect 256 contiguous Raman spectra every similar to 5 mu m from thin films (ca. 80 nm) formed by electrochemical derivatization of nickel electrodes. The cyanide stretching region of the Raman spectrum of the film is shown to be sensitive to iron oxidation state and is modeled by both univariate and multivariate correlations. Although both correlations fit the calibration set well, the multivariate (principle component regression or PCR) model's predictions of oxidation state are less sensitive to noise in the spectrum, yielding a much smoother oxidation state profile than the univariate model. Oxidation state profiles with spatial resolution of approximately 5 mu m are shown for a nickel hexacyanoferrate derivatized electrode in reduced, intermediate, and oxidized states. In situ oxidation stare profiles indicate that the 647.1 nm laser illumination photo-oxidizes the derivatized electrodes. This observation is confirmed using photoelectrochemical methods. (C) 1999 The Electrochemical Society. S0013-4651(97)05-063-5. All rights reserved. C1 Univ Washington, Dept Chem Engn, Seattle, WA 98195 USA. Pacific NW Natl Lab, Richland, WA 99352 USA. RP Haight, SM (reprint author), Univ Washington, Dept Chem Engn, Seattle, WA 98195 USA. NR 34 TC 26 Z9 26 U1 1 U2 9 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 65 SOUTH MAIN STREET, PENNINGTON, NJ 08534 USA SN 0013-4651 J9 J ELECTROCHEM SOC JI J. Electrochem. Soc. PD MAY PY 1999 VL 146 IS 5 BP 1866 EP 1872 DI 10.1149/1.1391857 PG 7 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA 197AW UT WOS:000080343300043 ER PT J AU Stein, DJ Hetherington, DL Cecchi, JL AF Stein, DJ Hetherington, DL Cecchi, JL TI Investigation of the kinetics of tungsten chemical mechanical polishing in potassium iodate-based slurries II. Roles of colloid species and slurry chemistry SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID ATOMIC-SCALE; FRICTION AB We investigated the role of colloid species and slurry chemistry in tungsten chemical mechanical polishing. Specifically, we measured polish rate and process temperature in potassium iodate-based slurries as a function of colloid species and concentration, slurry pH, and potassium iodate concentration, as well as polish pressure and polish rotation rate. We investigated slurries containing yttrium-, zirconium-, cerium, and aluminum-based oxide and hydroxide colloids. We found that the colloid species had a large effect on polish rate and process temperature. The colloids showed two orders of magnitude in the polish rate range from similar to 15 to similar to 1975 Angstrom min(-1) under otherwise identical experimental conditions (same polisher, pad, slurry chemistry, pressure, and rotation rates). Colloids of the same metal species from different sources also showed a large range in polish rates. Process temperature was a function of colloid species, however, the trend in polish rate did not always follow that of process temperature. Both polish rate and process temperature were dependent on potassium iodate concentration and slurry pH (controlled with a buffer). We also introduce a heuristic polish mechanism to investigate the role of the colloid surface chemistry and its interaction with the tungsten surface. The data indicate that the surface characteristics of the colloid and how this surface interacts with the tungsten surface play a significant role in the mechanism of tungsten removal during polish. (C) 1999 The Electrochemical Society. S0013-4651(98)09-034-X. All rights reserved. C1 Univ New Mexico, Dept Chem & Nucl Engn, Albuquerque, NM 87131 USA. Sandia Natl Labs, Microelect Dev Lab, Albuquerque, NM 87185 USA. RP Stein, DJ (reprint author), Univ New Mexico, Dept Chem & Nucl Engn, Albuquerque, NM 87131 USA. NR 8 TC 35 Z9 36 U1 0 U2 1 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 65 SOUTH MAIN STREET, PENNINGTON, NJ 08534 USA SN 0013-4651 J9 J ELECTROCHEM SOC JI J. Electrochem. Soc. PD MAY PY 1999 VL 146 IS 5 BP 1934 EP 1938 DI 10.1149/1.1391869 PG 5 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA 197AW UT WOS:000080343300055 ER PT J AU Smallwood, DO Cap, JS AF Smallwood, DO Cap, JS TI Salvaging pyrotechnic data with minor overloads and offsets SO JOURNAL OF THE IEST LA English DT Article DE pyrotechnic; shock; wavelets; shock response spectrum; data correction AB Data are sometimes presented with serious flaws, such as saturation, over-range, zero shifts, and impulsive noise, including much of the available pyrotechnic data. Obviously, these data should not be used if possible. However, we ale sometimes forced to use these data as the only data available. A method to salvage these data using wavelets is discussed. The results must be accepted with the understanding that the answers ale ci-edible, not necessarily correct. None of the methods will recover information lost due to saturation and over-range with the subsequent nonlinear behavior of the data acquisition system. The results are illustrated using analytical examples and flawed pyrotechnic data. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Smallwood, DO (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 6 TC 1 Z9 2 U1 0 U2 1 PU INST ENVIRONMENTAL SCI TECHNOLOGY PI MT PROSPECT PA 940 E NORTHWEST HIGHWAY, MT PROSPECT, IL 60056 USA SN 1052-2883 J9 J IEST JI J. IEST PD MAY-JUN PY 1999 VL 42 IS 3 BP 27 EP 35 PG 9 WC Engineering, Environmental; Environmental Sciences; Instruments & Instrumentation SC Engineering; Environmental Sciences & Ecology; Instruments & Instrumentation GA 210LL UT WOS:000081106900004 ER PT J AU Di Rosa, MD Farrow, RL AF Di Rosa, MD Farrow, RL TI Cross sections of photoionization and ac Stark shift measured from Doppler-free B <- X(0,0) excitation spectra of CO SO JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS LA English DT Article ID ENHANCED MULTIPHOTON-IONIZATION; LASER-INDUCED FLUORESCENCE; CARBON-MONOXIDE; 2-PHOTON ABSORPTION; COMBUSTION GASES; RYDBERG STATES; ATOMIC OXYGEN; SPECTROSCOPY; XENON; PHOTODISSOCIATION AB Using high-resolution, Doppler-free spectroscopy, we recorded through resonance-enhanced multiphoton ionization the response of two-photon rotational lines of the Q-branch of CO B <-- X(0, 0) to an independent photoionizing optical field. In direct proportion to the photoionization intensity, transitions Q(0)-Q(12) were lifetime broadened and shifted toward positive frequency, from which we extracted absolute cross sections of photoionization (sigma(i)) and Stark shift (sigma(s)), respectively. Cross sections of sigma(i) = 10 +/- 3 x 10(-18) cm(2) and sigma(s) = 7 +/- 2 x 10(-18) cm(2) were determined for the case of photoionizing light at 230 nm, tuned in near resonance with the two-photon transition. Photoionization by 345-nm light resulted in similar cross sections, of sigma(i) = 6 +/- 2 x 10-18 cm(2) and sigma(s) = 8 +/- 2 x 10(-18) cm(2). We observed a variation of sigma(i) and sigma(s) with rotational level for photoionization at 230 nm. (C) 1999 Optical Society of America [S0740-3224(99)01805-6]. C1 Sandia Natl Labs, Combust Res Facil, Livermore, CA 94550 USA. RP Di Rosa, MD (reprint author), Sandia Natl Labs, Combust Res Facil, Livermore, CA 94550 USA. NR 38 TC 16 Z9 16 U1 0 U2 7 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0740-3224 J9 J OPT SOC AM B JI J. Opt. Soc. Am. B-Opt. Phys. PD MAY PY 1999 VL 16 IS 5 BP 861 EP 870 DI 10.1364/JOSAB.16.000861 PG 10 WC Optics SC Optics GA 195AL UT WOS:000080226900021 ER PT J AU Ino, A Kim, C Mizokawa, T Shen, ZX Fujimori, A Takaba, M Tamasaku, K Eisaki, H Uchida, S AF Ino, A Kim, C Mizokawa, T Shen, ZX Fujimori, A Takaba, M Tamasaku, K Eisaki, H Uchida, S TI Fermi surface and band dispersion in La2-xSrxCuO4 SO JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN LA English DT Letter DE La2-xSrxCuO4; ARPES; Fermi surface; band dispersion; superconducting gap; doping dependence ID ANGLE-RESOLVED PHOTOEMISSION; ELECTRONIC-STRUCTURE; SUPERCONDUCTING STATE; OXIDE SUPERCONDUCTORS; PSEUDOGAP BEHAVIOR; DOPING DEPENDENCE; GAP ANISOTROPY; TEMPERATURE; BI2SR2CACU2O8+DELTA; EVOLUTION AB Using angle-resolved photoemission spectroscopy (ARPES), we observe the band structure, the Fermi surface and their doping dependences in La2-xSrxCuO4. The results reveal that the Fermi surface undergoes a dramatic change: it is holelike and centered at (pi,pi) in underdoped (x = 0.1) and optimally doped (x = 0.15) samples as in other cuprates, while it is electronlike and centered at (0.0) in heavily overdoped (x = 0.3) ones. The peak in the ARPES spectra near (pi/2,pi/2) is broad and weak unlike that in other cuprates. In the underdoped and optimally doped samples, a superconducting gap (Delta = 10-15 meV) is observed near (pi, 0). C1 Univ Tokyo, Dept Phys, Bunkyo Ku, Tokyo 1130033, Japan. Stanford Univ, Dept Appl Phys, Stanford, CA 94305 USA. Stanford Univ, Stanford Synchrotron Radiat Lab, Stanford, CA 94305 USA. Univ Tokyo, Dept Superconduct, Bunkyo Ku, Tokyo 1130033, Japan. RP Ino, A (reprint author), Univ Tokyo, Dept Phys, Bunkyo Ku, Tokyo 1130033, Japan. EM iao@wyvern.phys.s.u-tokyo.ac.jp RI Mizokawa, Takashi/E-3302-2015; Tamasaku, Kenji/N-7907-2015 OI Mizokawa, Takashi/0000-0002-7682-2348; NR 37 TC 115 Z9 117 U1 1 U2 13 PU PHYSICAL SOC JAPAN PI MINATO-KU PA EISHIN-KAIHATSU BLDG, 5TH FLR, 5-34-3 SHINBASHI, MINATO-KU, TOKYO 105-0004, JAPAN SN 0031-9015 J9 J PHYS SOC JPN JI J. Phys. Soc. Jpn. PD MAY PY 1999 VL 68 IS 5 BP 1496 EP 1499 DI 10.1143/JPSJ.68.1496 PG 4 WC Physics, Multidisciplinary SC Physics GA 200RA UT WOS:000080552800009 ER PT J AU Kim, YJ Gao, Y Herman, GS Thevuthasan, S Jiang, W McCready, DE Chambers, SA AF Kim, YJ Gao, Y Herman, GS Thevuthasan, S Jiang, W McCready, DE Chambers, SA TI Growth and structure of epitaxial CeO2 by oxygen-plasma-assisted molecular beam epitaxy SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A LA English DT Article ID RAY PHOTOELECTRON DIFFRACTION; ENERGY; CATALYSTS; SI(111); SILICON; DEPOSITION; SCATTERING; SURFACES; LAYERS; AUGER AB The epitaxial growth of CeO2 films on SrTiO3(001) has been investigated over a wide range of growth parameters using oxygen-plasma-assisted molecular beam epitaxy. The lattice mismatch for CeO2 on SrTiO3(001) is 2.0% (compressive) if the film nucleates with a 45 degrees rotation about [001] relative to the substrate (i.e., CeO2(001)\\SrTiO3(001) and CeO2[110]\\SrTiO3[100]). pure-phase, single-crystalline epitaxial films of CeO2(001) with the above epitaxial relationship readily grew on SrTiO3(001) for substrate temperatures ranging from 550 to 700 degrees C. However, small amounts of (111) and (220) minority orientations also nucleated at the higher substrate temperatures. In addition, the film surface was observed to become progressively smoother with increasing substrate temperature due to more extensive island agglomeration. The highest-quality him surface grown at 700 degrees C is unreconstructed and oxygen terminated. (C) 1999 American Vacuum Society. [S0734-2101(99)02903-6]. C1 Pacific NW Natl Lab, Environm Mol Sco Lab, Richland, WA 99352 USA. RP Chambers, SA (reprint author), Taejon Natl Univ Technol, Dept Chem Technol, Taejon, South Korea. EM sa.chambers@pnl.gov NR 26 TC 45 Z9 45 U1 4 U2 16 PU A V S AMER INST PHYSICS PI MELVILLE PA STE 1 NO 1, 2 HUNTINGTON QUADRANGLE, MELVILLE, NY 11747-4502 USA SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A PD MAY-JUN PY 1999 VL 17 IS 3 BP 926 EP 935 DI 10.1116/1.581666 PG 10 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 197BD UT WOS:000080344000038 ER PT J AU Gao, Y Herman, GS Thevuthasan, S Peden, CHF Chambers, SA AF Gao, Y Herman, GS Thevuthasan, S Peden, CHF Chambers, SA TI Epitaxial growth and characterization of Ce1-xZrxO2 thin films SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A LA English DT Article ID CEO2-ZRO2 SOLID-SOLUTIONS; OXYGEN STORAGE CAPACITY; ELECTRONIC-STRUCTURE; 3-WAY CATALYSTS; CERIUM OXIDE; REDUCTION; NO; TIO2(110); SURFACES; CE AB Epitaxial films of mixed Ce1-xZrxO2(001) oxides with x less than or equal to 0.3 have been grown on SrTiO3(001) by oxygen-plasma-assisted molecular beam epitaxy. The film growth at 600 degrees C is predominantly nucleation and growth of three-dimensional islands. The films become much smoother after rapid thermal annealing at 700 degrees C for 30 s in the oxygen plasma. High-energy ion channeling reveals that Zr atoms substitutionally incorporate at cation sites in the CeO2 lattice for all doping levels, leading to Ce1-xZrxO2 solid solutions. Analysis of Zr 3d and Ce 3d core-level binding energies shows that the oxidation state of both Zr and Ce is +4. Lattice distortion induced by incorporation of Zr in the CeO2 lattice becomes prevalent for high doping levels and surface roughen accordingly. (C) 1999 American Vacuum Society. [S0734-2101(99)04303-1]. C1 Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. EM yufei.gao@pnl.gov OI Peden, Charles/0000-0001-6754-9928 NR 37 TC 21 Z9 21 U1 1 U2 10 PU A V S AMER INST PHYSICS PI MELVILLE PA STE 1 NO 1, 2 HUNTINGTON QUADRANGLE, MELVILLE, NY 11747-4502 USA SN 0734-2101 EI 1520-8559 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A PD MAY-JUN PY 1999 VL 17 IS 3 BP 961 EP 969 DI 10.1116/1.581671 PG 9 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 197BD UT WOS:000080344000043 ER PT J AU Hahn, YB Hays, DC Donovan, SM Abernathy, CR Han, J Shul, RJ Cho, H Jung, KB Pearton, SJ AF Hahn, YB Hays, DC Donovan, SM Abernathy, CR Han, J Shul, RJ Cho, H Jung, KB Pearton, SJ TI Effect of additive noble gases in chlorine-based inductively coupled plasma etching of GaN, InN, and AlN SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article ID FIELD-EFFECT TRANSISTORS; MOLECULAR-BEAM EPITAXY; OHMIC CONTACTS; III-NITRIDES; PERFORMANCE; GROWTH AB The effects of additive noble gases, He, Ar and Xe to chlorine-based inductively coupled plasmas (ICPs) for etching of GaN, AlN and InN were studied in terms of etch rate and selectivity. The etch rates were greatly affected by the chlorine concentration, rf chuck power and ICP source power. The highest etch rates for InN were obtained with Cl-2/Xe, while the highest rates for AIN and GaN were obtained with Cl-2/He. It was confirmed that efficient breaking of the III-nitrogen bond is crucial for higher etch rates. The InN etching was dominated by physical sputtering; the GaN and AIN etch rates were limited by initial breaking of the III-nitrogen bond. Maximum selectivities of similar to 80 fur InN to GaN and InN to AIN were obtained with the Cl-2-based discharges. (C) 1999 American Vacuum Society. [S0734-2101(99)04603-5]. C1 Univ Florida, Dept Mat Sci & Engn, Gainesville, FL 32611 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Hahn, YB (reprint author), Chonbuk Natl Univ, Sch Chem Engn & Technol, Chonju 561756, South Korea. NR 26 TC 30 Z9 30 U1 3 U2 12 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 1999 VL 17 IS 3 BP 768 EP 773 DI 10.1116/1.581647 PG 6 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 197BD UT WOS:000080344000015 ER PT J AU Li, XN Niles, DW Hasoon, FS Matson, RJ Sheldon, P AF Li, XN Niles, DW Hasoon, FS Matson, RJ Sheldon, P TI Effect of nitric-phosphoric acid etches on material properties and back-contact formation of CdTe-based solar cells SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article ID FILM CADMIUM TELLURIDE AB Forming a low-resistance contact to p-type CdTe is a critical issue for successful commercialization of CdTe-based photovoltaic devices. One solution to this problem has been to incorporate surface pretreatments to facilitate contact formation. In this article, the effects of a nitric-phosphoric (NP) acid pretreatment on material properties and device performance are investigated for polycrystalline CdTe-based devices. We demonstrate that the NP acid pretreatment, when applied to CdTe thin films, forms a thick, highly conductive Te layer on the back surface of the film and on exposed grain boundaries. When etched under optimal conditions, this results in CdS/CdTe devices with reduced series resistance and enhanced performance. On the other hand, we find that the NP etch preferentially etches grain boundaries. Overetching can result in complete device failure by forming shunt paths that extend to the heterointerface. Therefore, carefully controlling the etch concentration and duration is critical to optimizing device performance. [S0734-2101(99)05403-2]. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Li, XN (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. NR 18 TC 41 Z9 46 U1 0 U2 9 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 1999 VL 17 IS 3 BP 805 EP 809 DI 10.1116/1.581651 PG 5 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 197BD UT WOS:000080344000020 ER PT J AU Chaturvedi, S Strongin, DR AF Chaturvedi, S Strongin, DR TI Adsorption and thermal decomposition of C2D5I on the (110) and (111) planes of NiAl: A temperature programmed deposition and x-ray photoelectron spectroscopy study SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article ID BETA-HYDRIDE ELIMINATION; ETHYL IODIDE; METAL-SURFACES; AG(111); PT(111); PHOTOCHEMISTRY; HYDROCARBONS; MECHANISM; CHEMISTRY; NIAL(110) AB This study investigates the adsorption and the subsequent thermal decompoistion of d(5)-iodoethane (C2D5I) on the (110) and (111) planes of NiAl using temperature programmed desorption (TPD) and x-ray photoelectron spectroscopy (XPS). Both I 3 d(5/2) and C 1 s XPS data show that C2D5I adsorbs molecularly on both NiAl surfaces at 120 K. Upon heating the sample, the C-I bond starts to cleave and the scission of this bond is complete on NiAl(110) and NiAl(111) by 150 and 300 K, respectively. It is suspected that this cleavage results in the formation of C2D5(ad) and I-(ad). TPD results show that the thermal decomposition of C2D5(ad) yields C2D4 and D-2 as the main products on both the surfaces. The main difference in the decomposition products of C2D5(ad) species on the two surfaces is that desorption of C2D4 occurs on NiAl(111) at similar to 315 K, similar to 50 K higher than the corresponding value for NiAl(110). (C) 1999 American Vacuum Society. [S0734-2101(99)00603-X]. C1 Temple Univ, Dept Chem, Philadelphia, PA 19122 USA. Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. RP Strongin, DR (reprint author), Temple Univ, Dept Chem, Philadelphia, PA 19122 USA. NR 29 TC 4 Z9 4 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 1999 VL 17 IS 3 BP 810 EP 816 DI 10.1116/1.581652 PG 7 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 197BD UT WOS:000080344000021 ER PT J AU Nesting, DC Kouvetakis, J Hearne, S Chason, E Tsong, IST AF Nesting, DC Kouvetakis, J Hearne, S Chason, E Tsong, IST TI Real-time monitoring of structure and stress evolution of boron films grown on Si(100) by ultrahigh vacuum chemical vapor deposition SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article ID X-RAY REFLECTIVITY; THIN-FILM; SEGREGATION AB The morphology and biaxial stress of amorphous boron films grown on silicon at 630 degrees C have been determined in situ and in real time using energy dispersive x-ray reflectivity and multiple-beam optical stress sensor techniques. The capability to determine the morphology and stress of light-element thin films in situ and in real time provides a unique opportunity to optimize the parameters of thin film deposition under chemical vapor deposition conditions. (C) 1999 American Vacuum Society. [S0734-2101(99)05203-3]. C1 Arizona State Univ, Dept Chem & Biochem, Tempe, AZ 85287 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. Arizona State Univ, Dept Phys & Astron, Tempe, AZ 85287 USA. RP Nesting, DC (reprint author), Arizona State Univ, Dept Chem & Biochem, Tempe, AZ 85287 USA. NR 11 TC 6 Z9 6 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 1999 VL 17 IS 3 BP 891 EP 894 DI 10.1116/1.581661 PG 4 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 197BD UT WOS:000080344000032 ER PT J AU Herman, GS Henderson, MA Starkweather, KA McDaniel, EP AF Herman, GS Henderson, MA Starkweather, KA McDaniel, EP TI Mass spectroscopy of recoiled ions, secondary ion mass spectroscopy, and Auger electron spectroscopy investigation of Y2O3-stabilized ZrO2(100) and (110) SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article ID YTTRIA-STABILIZED ZIRCONIA; SPUTTERING YIELDS; SEGREGATION; SURFACES; SCATTERING AB We have studied the (100) and (110) surfaces of yttria-stabilized cubic ZrO2 using Auger electron spectroscopy, low energy electron diffraction (LEED), direct recoil spectroscopy, mass spectroscopy of recoiled ions (MSRI), and secondary ion mass spectroscopy (SIMS). The concentration of yttrium at the surface was weakly influenced by the surface structure under the experimental conditions investigated. Both MSRI and SIMS indicated a more enhanced yttrium signal than zirconium signal at the surface compared to the respective bulk concentrations. The surfaces were not very well ordered as indicated by LEED. The yttria-stabilized cubic ZrO2 single crystal surfaces may not be a suitable model material for pure phase ZrO2 surfaces due to significant yttria concentrations at the surface. (C) 1999 American Vacuum Society. [S0734-2101(99)02603-2]. C1 Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Herman, GS (reprint author), Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. NR 28 TC 3 Z9 3 U1 4 U2 5 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 1999 VL 17 IS 3 BP 939 EP 944 DI 10.1116/1.581668 PG 6 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 197BD UT WOS:000080344000040 ER PT J AU Maya, L Anovitz, LM Thundat, T Yust, CS AF Maya, L Anovitz, LM Thundat, T Yust, CS TI Optical and mechanical consequences of microstructural alteration of alpha platinum dioxide films SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article AB The microstructure of sputtered alpha platinum dioxide consists of a porous random assembly of platelets. A sweeping motion with very light pressure, by either a sharp or blunt object, leaves a track clearly visible, in reflected light, that stands in contrast to the opaque brown background of the intact film. Microstructural analysis utilizing atomic force microscopy revealed a flattening of the platelets in the affected areas. High reflectivity of the flattened portion is apparently a consequence of the relatively high refractive index of this material. X-ray diffraction by the flattened platelets shows a significant enhancement of the intensity of the 001 reflection corresponding to the alignment of the crystals parallel to the substrate. The work required to flatten the platelets along a microscopic track was deduced from sensitive friction force measurements. Electrical resistivity of the flattened film is moderately lower than that of the intact film. The phenomenon described here might be of importance for data storage or for alignment in lithographic reproduction of multilevel electronic circuits. (C) 1999 American Vacuum Society. [S0734-2101(99)04903-9]. C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. Oak Ridge Natl Lab, Div Life Sci, Oak Ridge, TN 37831 USA. RP Maya, L (reprint author), Oak Ridge Natl Lab, Div Chem & Analyt Sci, POB 2008, Oak Ridge, TN 37831 USA. RI Anovitz, Lawrence/P-3144-2016 OI Anovitz, Lawrence/0000-0002-2609-8750 NR 9 TC 1 Z9 1 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 1999 VL 17 IS 3 BP 1036 EP 1039 DI 10.1116/1.581679 PG 4 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 197BD UT WOS:000080344000052 ER PT J AU Zhang, L Lester, LF Shul, RJ Willison, CG Leavitt, RP AF Zhang, L Lester, LF Shul, RJ Willison, CG Leavitt, RP TI Inductively coupled plasma etching of III-V antimonides in BCl3/Ar and Cl-2/Ar SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B LA English DT Article ID DIODE-LASER; MU-M; SEMICONDUCTORS; GAAS; GASB AB Inductively coupled plasma (ICP) etching characteristics of GaSb and AlGaAsSb have been investigated in BCl3/Ar and Cl-2/Ar plasmas. The etch rates and selectivity between GaSb and AlGaAsSb are reported as functions of plasma chemistry, ICP power, rf self-bias, and chamber pressure. It is found that physical sputtering desorption of the etch products plays a dominant role in BCl3/Ar ICP etching, while in Cl-2/Ar plasma, the chemical reaction dominates the etching. GaSb etch rates exceeding 2 mu m/min are achieved in Cl-2/Ar plasmas with smooth surfaces and anisotropic profiles. In BCl3/Ar plasmas, etch rates of 5100 and 4200 Angstrom/min are obtained for GaSb and AlGaAsSb, respectively. The surfaces of both GaSb and AlGaAsSb etched in BCl3/Ar plasmas remain smooth and stoichiometric over the entire range of plasma conditions investigated. This result is attributed to effective removal of etch products by physical sputtering. For a wide range of plasma conditions, the selectivity between GaSb and AlGaAsSb is close to unity, which is desirable for fabricating etched mirrors and gratings for Sb-based midinfrared laser diodes. (C) 1999 American Vacuum Society. C1 Univ New Mexico, Ctr High Technol Mat, Albuquerque, NM 87106 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. USA, Res Lab, Adelphi, MD 20783 USA. RP Zhang, L (reprint author), Univ New Mexico, Ctr High Technol Mat, Albuquerque, NM 87106 USA. NR 15 TC 20 Z9 21 U1 0 U2 13 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1071-1023 J9 J VAC SCI TECHNOL B JI J. Vac. Sci. Technol. B PD MAY-JUN PY 1999 VL 17 IS 3 BP 965 EP 969 DI 10.1116/1.590678 PG 5 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA 206AD UT WOS:000080853100011 ER PT J AU Jensen, JA Rider, KB Chen, Y Salmeron, M Somorjai, GA AF Jensen, JA Rider, KB Chen, Y Salmeron, M Somorjai, GA TI High pressure, high temperature scanning tunneling microscopy SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B LA English DT Article ID SUM-FREQUENCY GENERATION; ULTRAVIOLET RAMAN-SPECTROSCOPY; ATMOSPHERIC-PRESSURE; IN-SITU; HYDROGENATION; CATALYSTS; CO AB The design and performance of a high pressure, high temperature scanning tunneling microscope (HPHT-STM) system is described. The system combines an ultrahigh vacuum surface analysis/preparation chamber with a variable pressure (5 x 10(-10) Torr-1 atm) and temperature (300-675 K) STM. The STM chamber can be isolated by three gate valves and filled with 1 arm of any gas mixture. The composition of the gas can be monitored by gas chromatography. A load-lock mechanism allows the transfer of samples and tips into the chamber without exposing it to air. Heating at high pressure is achieved using a halogen lamp beneath the sample. By switching between tungsten and gold tips, the microscope can be used in both oxidizing and reducing environments at room temperature, and reducing environments at elevated temperatures. This instrument allows the exploration of surfaces in a pressure regime that few other surface sensitive techniques can work in. (C) 1999 American Vacuum Society. [S0734-211X(99)07403-X]. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. RP Jensen, JA (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. NR 11 TC 49 Z9 49 U1 0 U2 12 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1071-1023 J9 J VAC SCI TECHNOL B JI J. Vac. Sci. Technol. B PD MAY-JUN PY 1999 VL 17 IS 3 BP 1080 EP 1084 DI 10.1116/1.590697 PG 5 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA 206AD UT WOS:000080853100032 ER PT J AU Monteiro, OR AF Monteiro, OR TI Novel metallization technique for filling 100-nm-wide trenches and vias with very high aspect ratio SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B LA English DT Article ID MAGNETRON SPUTTER-DEPOSITION; IMMERSION ION-IMPLANTATION; METAL PLASMA IMMERSION; MACROPARTICLE AB We have developed a metallization method that successfully satisfies all the requirements for the next several generations of integrated circuits (ICs). This method was used to deposit fully conformal diffusion barriers of Ta and TaN as well as Cu seeding layers in 100-nm-wide trenches and vias with (depth:width) aspect ratios up to 8:1. The diffusion barrier and seeding layer are critical for the implementation of copper metallization schemes. This technique was also used to completely fill high aspect ratio trenches with copper. A fully ionized metal plasma deposition method is used in which the ion energy is varied and controlled as a function of time throughout the deposition process. No limitation of the process with respect to trench width or aspect ratio has been observed yet, suggesting the process can be used for ICs with sub-100 nm linewidths. (C) 1999 Ameircan Vacuum Society. [S0734-211X(99)02003-X]. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Monteiro, OR (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. NR 21 TC 49 Z9 49 U1 1 U2 9 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1071-1023 J9 J VAC SCI TECHNOL B JI J. Vac. Sci. Technol. B PD MAY-JUN PY 1999 VL 17 IS 3 BP 1094 EP 1097 DI 10.1116/1.590701 PG 4 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA 206AD UT WOS:000080853100036 ER PT J AU Mars, DE Babic, DI Kaneko, Y Chang, YL Subramanya, S Kruger, J Perlin, P Weber, ER AF Mars, DE Babic, DI Kaneko, Y Chang, YL Subramanya, S Kruger, J Perlin, P Weber, ER TI Growth of 1.3 mu m InGaAsN laser material on GaAs by molecular beam epitaxy SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B LA English DT Article; Proceedings Paper CT 17th North American Conference on Molecular Beam Epitaxy (NAMBE-17) CY OCT 04-07, 1998 CL STATE COLL, PENNSYLVANIA ID QUANTUM-WELL LASERS; GAINNAS; DIODES; PLASMA; ENERGY AB We have grown bulk GaAsN and InGaAsN quantum well laser structures using molecular beam epitaxy and an electron cyclotron resonance plasma source with Nz gas. X-ray diffraction measurements in GaAsN grown on GaAs were used to determine the concentration of N in the range of 0% to similar to 2%. Room temperature photoluminescence (PL) measurements were done on quantum well test structures and half lasers. The PL intensity decreases and the PL full width at half maximum (FWHM) increases as the wavelength increases. Rapid thermal annealing (RTA) at 850 degrees C for 10 s improves the PL intensity by a factor of 8 and increases the PL peak emission energy by 80 meV. The longest wavelength measured to date in laser structures with single quantum wells of InGaAsN is 1480 nm with a FWHM of 60 meV. Samples with and without RTA were fabricated into broad-area lasers with dimensions of 50 x 500 mu m(2). Laser devices with RTA operated in the pulsed mode at 1.3 mu m with a threshold current density of 9.5 kA/cm(2). (C) 1999 American Vacuum Society. [S0734-211X(99)06103-X]. C1 Hewlett Packard Co, Res Labs, Palo Alto, CA 94304 USA. Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Calif Berkeley, Berkeley, CA 94720 USA. RP Mars, DE (reprint author), Hewlett Packard Co, Res Labs, 3500 Deer Creek Rd,B26M-7, Palo Alto, CA 94304 USA. NR 17 TC 59 Z9 60 U1 2 U2 5 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1071-1023 J9 J VAC SCI TECHNOL B JI J. Vac. Sci. Technol. B PD MAY-JUN PY 1999 VL 17 IS 3 BP 1272 EP 1275 DI 10.1116/1.590738 PG 4 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA 206AD UT WOS:000080853100078 ER PT J AU Wilson, CC Brown, RC Korber, BT Wilkes, BM Ruhl, DJ Sakamoto, D Kunstman, K Luzuriaga, K Hanson, IC Widmayer, SM Wiznia, A Clapp, S Ammann, AJ Koup, RA Wolinsky, SM Walker, BD AF Wilson, CC Brown, RC Korber, BT Wilkes, BM Ruhl, DJ Sakamoto, D Kunstman, K Luzuriaga, K Hanson, IC Widmayer, SM Wiznia, A Clapp, S Ammann, AJ Koup, RA Wolinsky, SM Walker, BD CA Ariel Project Investigators TI Frequent detection of escape from cytotoxic T-lymphocyte recognition in perinatal human immunodeficiency virus (HIV) type 1 transmission: the Ariel Project for the Prevention of Transmission of HIV from Mother to Infant SO JOURNAL OF VIROLOGY LA English DT Article ID MATERNAL VIRAL LOAD; VERTICAL TRANSMISSION; ZIDOVUDINE TREATMENT; FINE SPECIFICITY; IN-VIVO; NEUTRALIZING ANTIBODY; CHILD TRANSMISSION; PRIMARY INFECTION; GENETIC-VARIATION; IMMUNE-RESPONSES AB Host immunologic factors, including human immunodeficiency virus (HIV)-specific cytotoxic T lymphocytes (CTL), are thought to contribute to the control of HIV type 1 (HIV-1) replication and thus delay disease progression in infected individuals. Host immunologic factors are also likely to influence perinatal transmission of HIV-1 from infected mother to infant. In this study, the potential role of CTL in modulating HIV-1 transmission from mother to infant was examined in 11 HIV-1-infected mothers, 3 of whom transmitted virus to their offspring. Frequencies of HIV-1-specific human leukocyte antigen class I-restricted CTL responses and viral epitope amino acid sequence variation were determined in the mothers and their infected infants. Maternal HIV-1-specific CTL clones were derived from each of the HIV-l-infected pregnant women. Amino acid substitutions within the targeted CTL epitopes were more frequently identified in transmitting mothers than in nontransmitting mothers, and immune escape from CTL recognition was detected in all three transmitting mothers but in only one of eight nontransmitting mothers. The majority of viral sequences obtained from the HIV-1-infected infant blood samples were susceptible to maternal CTL. These findings demonstrate that epitope amino acid sequence variation and escape from CTL recognition occur more frequently in mothers that transmit HIV-1 to their infants than in those who do not. However, the transmitted virus can be a CTL susceptible form, suggesting inadequate in vivo immune control. C1 Northwestern Univ, Sch Med, Chicago, IL 60611 USA. Massachusetts Gen Hosp, Ctr AIDS Res, Boston, MA 02114 USA. Massachusetts Gen Hosp, Infect Dis Unit, Boston, MA 02114 USA. Harvard Univ, Sch Med, Boston, MA 02114 USA. Santa Fe Inst, Santa Fe, NM 87501 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Massachusetts, Sch Med, Worcester, MA 01605 USA. Baylor Coll Med, Dept Pediat, Houston, TX 77030 USA. Childrens Diagnost & Treatment Ctr, Ft Lauderdale, FL 33301 USA. Univ Calif San Francisco, Med Ctr, San Francisco, CA 94143 USA. Rockefeller Univ, Aaron Diamond AIDS Res Ctr, New York, NY 10016 USA. RP Wolinsky, SM (reprint author), Northwestern Univ, Sch Med, 303 E chicago Ave, Chicago, IL 60611 USA. RI Wolinsky, Steven/B-2893-2012; OI Wolinsky, Steven/0000-0002-9625-6697; Korber, Bette/0000-0002-2026-5757 FU NIAID NIH HHS [R37AI28568, R37 AI028568]; NICHD NIH HHS [HD-31756] NR 64 TC 61 Z9 61 U1 0 U2 0 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1325 MASSACHUSETTS AVENUE, NW, WASHINGTON, DC 20005-4171 USA SN 0022-538X J9 J VIROL JI J. Virol. PD MAY PY 1999 VL 73 IS 5 BP 3975 EP 3985 PG 11 WC Virology SC Virology GA 185ZG UT WOS:000079701100055 PM 10196293 ER PT J AU Novitsky, VA Montano, MA McLane, MF Renjifo, B Vannberg, F Foley, BT Ndung'u, TP Rahman, M Makhema, MJ Marlink, R Essex, M AF Novitsky, VA Montano, MA McLane, MF Renjifo, B Vannberg, F Foley, BT Ndung'u, TP Rahman, M Makhema, MJ Marlink, R Essex, M TI Molecular cloning and phylogenetic analysis of human immunodeficiency virus type 1 subtype C: a set of 23 full-length clones from Botswana SO JOURNAL OF VIROLOGY LA English DT Article ID T-LYMPHOCYTE RESPONSES; HIV TYPE-1; SOUTH-AFRICA; TRANSMISSION; SEQUENCES; INFECTION; ISOLATE; MODE; GAG AB To better understand the virological aspect of the expanding AIDS epidemic in southern Africa, a set of 23 near-full-length clones of human immunodeficiency virus type 1 (HIV-1) representing eight AIDS patients from Botswana were sequenced and analyzed phylogenetically. All study viruses from Botswana belonged to HIV-1 subtype C. The interpatient diversity of the clones from Botswana was higher than among full-length isolates of subtype B or among a set of full-length HIV-1 genomes of subtype C from India (mean value of 9.1% versus 6.5 and 4.3%, respectively; P < 0.0001 for both comparisons). Similar results were observed in all genes across the entire viral genome. We suggest that the high level of HIV-1 diversity might be a typical feature of the sub type C epidemic in southern Africa. The reason or reasons for this diversity are unclear, but may include an altered replication efficiency of HIV-1 subtype C and/or the multiple introduction of different subtype C viruses. C1 Harvard Univ, Sch Publ Hlth, Dept Immunol & Infect Dis, Harvard AIDS Inst, Boston, MA 02115 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. AIDS STD Unit, Gaborone, Botswana. Princess Marina Hosp, Gaborone, Botswana. RP Essex, M (reprint author), Harvard Univ, Sch Publ Hlth, Dept Immunol & Infect Dis, Harvard AIDS Inst, FXB-402,651 Huntington Ave, Boston, MA 02115 USA. OI Foley, Brian/0000-0002-1086-0296 FU FIC NIH HHS [D43 TW000004, D43 TW00004]; NCI NIH HHS [R35 CA39805-13] NR 47 TC 102 Z9 102 U1 0 U2 2 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1325 MASSACHUSETTS AVENUE, NW, WASHINGTON, DC 20005-4171 USA SN 0022-538X J9 J VIROL JI J. Virol. PD MAY PY 1999 VL 73 IS 5 BP 4427 EP 4432 PG 6 WC Virology SC Virology GA 185ZG UT WOS:000079701100102 PM 10196340 ER PT J AU Phiefer, CB Palmer, RJ White, DC AF Phiefer, CB Palmer, RJ White, DC TI Comparison of relative photon flux from single cells of the bioluminescent marine bacteria Vibrio fischeri and Vibrio harveyi using photon-counting microscopy SO LUMINESCENCE LA English DT Article DE photon-counting; microscopy; Vibrio harveyi; Vibrio fischeri; confocal microscopy; bioluminescence ID EUPRYMNA-SCOLOPES; AUTOINDUCER; EXPRESSION; ANABAENA; PATTERN AB Photon counting microscopy was used to quantify relative photon flux from 616 single sessile cells of Vibrio harveyi and 180 single sessile cells of V. fischeri. V. fischeri cells all emitted light at nearly the same level (average 15.93 +/- 11.48 photons/min, range 0-58.9 photons/min) when bioluminescence was induced, whereas photon flux of V. harveyi single cells was extremely variable (average 10.51 +/- 20.60 photons/min, range 0-211 photons/min). Copyright (C) 1999 John Wiley & Sons, Ltd. C1 Univ Tennessee, Ctr Environm Biotechnol, Knoxville, TN 37932 USA. Oak Ridge Natl Labs, Div Environm Sci, Oak Ridge, TN USA. RP Palmer, RJ (reprint author), Univ Tennessee, Ctr Environm Biotechnol, 10515 Res Dr,Suite 300, Knoxville, TN 37932 USA. NR 22 TC 9 Z9 9 U1 0 U2 0 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 1522-7235 J9 LUMINESCENCE JI Luminescence PD MAY-JUN PY 1999 VL 14 IS 3 BP 147 EP + DI 10.1002/(SICI)1522-7243(199905/06)14:3<147::AID-BIO532>3.3.CO;2-3 PG 7 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 215PQ UT WOS:000081390600004 PM 10423575 ER PT J AU Frank, M Labov, SE Westmacott, G Benner, WH AF Frank, M Labov, SE Westmacott, G Benner, WH TI Energy-sensitive cryogenic detectors for high-mass biomolecule mass spectrometry SO MASS SPECTROMETRY REVIEWS LA English DT Review DE cryogenic detectors; calorimetric detectors; high-mass detectors; time-of-flight mass spectrometry ID SUPERCONDUCTING TUNNEL JUNCTION; SECONDARY-ELECTRON EMISSION; LASER-DESORPTION IONIZATION; X-RAY SPECTROMETERS; LARGE MOLECULAR-IONS; HIGH-RESOLUTION; PARTICLE DETECTORS; CLUSTER IONS; TIME; MICROCALORIMETERS AB Energy-sensitive calorimetric detectors that operate at low temperatures ("cryogenic detectors") have recently been applied for the first time as ion detectors in time-of-flight mass spectrometry Compared to conventional ionization-based detectors, which rely on secondary electron formation or the charge created in a semiconductor, cryogenic detectors measure low-energy solid stare excitations created by a particle impact This energy sensitivity of cryogenic defectors results in several potential advantages for TOF-MS. Cryogenic detectors are expected to have near 100% efficiency even for very large, slow-moving molecules, in contrast to microchannel plates whose efficiency dregs considerably at large mass. Thus, cryogenic detectors could contribute to extending the mass range accessible by TOF-MS and help improving detection limits. In addition, the energy resolution provided by cryogenic detectors carl be used for charge discrimination and studies of ion fragmentation. ion-detector interaction, and internal energies of large molecular ions. Cryogenic detectors could therefore prove to be a valuable diagnostic tool in TOF-MS. Here, we give a general introduction to the cryogenic detector types most applicable to TOF-MS including those types already used in several TOF-MS experiments. We review and compare the results of these experiments, discuss practical aspects of operating cryogenic detectors in TOF-MS systems, and describe potential near future improvements of cryogenic detectors for applications in mass spectrometry: (C) 1999 John Wiley & Sons, Inc. C1 Lawrence Livermore Natl Lab, Phys Directorate, Div 5, Livermore, CA 94551 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Human Genome, Instrumentat Grp, Berkeley, CA 94720 USA. RP Frank, M (reprint author), Lawrence Livermore Natl Lab, Phys Directorate, Div 5, POB 808,Mail Stop L-418, Livermore, CA 94551 USA. RI Frank, Matthias/O-9055-2014 NR 105 TC 64 Z9 64 U1 1 U2 13 PU WILEY-BLACKWELL PI HOBOKEN PA 111 RIVER ST, HOBOKEN 07030-5774, NJ USA SN 0277-7037 EI 1098-2787 J9 MASS SPECTROM REV JI Mass Spectrom. Rev. PD MAY-AUG PY 1999 VL 18 IS 3-4 BP 155 EP 186 DI 10.1002/(SICI)1098-2787(1999)18:3/4<155::AID-MAS1>3.0.CO;2-W PG 32 WC Spectroscopy SC Spectroscopy GA 251XV UT WOS:000083472400001 PM 10568040 ER PT J AU Mandrus, D Keppens, V Chakoumakos, BC AF Mandrus, D Keppens, V Chakoumakos, BC TI Spin-glass formation in Co2RuO4 SO MATERIALS RESEARCH BULLETIN LA English DT Article DE oxides; magnetic materials; neutron scattering; magnetic properties; magnetic structure ID BEHAVIOR AB Magnetic susceptibility and powder neutron diffraction results are reported on the cubic spinel Co2RuO4. These measurements indicate spin-glass formation in this compound, with a freezing temperature of about 16 K. Magnetic susceptibility results are also reported on ZnCoRuO4, a spinel in which only the Ru3+ ions are magnetic. No magnetic order was found in ZnCoRuO4 down to 2 K, indicating extremely weak interactions between the octahedral Ru3+ ions in these materials. (C) 1999 Elsevier Science Ltd. C1 Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Mandrus, D (reprint author), Oak Ridge Natl Lab, Div Solid State, POB 2008, Oak Ridge, TN 37831 USA. RI Mandrus, David/H-3090-2014; Chakoumakos, Bryan/A-5601-2016 OI Chakoumakos, Bryan/0000-0002-7870-6543 NR 21 TC 11 Z9 11 U1 0 U2 11 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0025-5408 J9 MATER RES BULL JI Mater. Res. Bull. PD MAY PY 1999 VL 34 IS 7 BP 1013 EP 1022 DI 10.1016/S0025-5408(99)00104-X PG 10 WC Materials Science, Multidisciplinary SC Materials Science GA 241MP UT WOS:000082887400002 ER PT J AU Beyerlein, IJ Landis, CM AF Beyerlein, IJ Landis, CM TI Shear-lag model for failure simulations of unidirectional fiber composites including matrix stiffness SO MECHANICS OF MATERIALS LA English DT Article DE fiber composites; shear-lag analysis; axial matrix stiffness; stress concentrations; plane linear elasticity; numerical simulation ID MICRO-RAMAN SPECTROSCOPY; STRESS-CONCENTRATIONS; INFLUENCE SUPERPOSITION; REINFORCED COMPOSITES; WEIBULL FIBERS; FRACTURE; BREAKS; REDISTRIBUTION; STATISTICS; STRENGTH AB In this paper, we develop a shear-lag model and an influence superposition technique to quickly compute the stresses and displacements in 2D unidirectional fiber composites in response to multiple fiber and matrix breaks. Unlike previous techniques, both the fiber and matrix are able to sustain axial load, and the governing shear-lag equations are derived based on the principle of virtual work and the finite element method. The main advantages of influence superposition techniques are that computation is tied to the amount of damage, rather than the entire volume considered and discretization is not needed, removing any uncertainties associated with meshing. For illustration, we consider a row of N (up to 301) contiguous fiber breaks and highlight important influences that N and the matrix-to-fiber stiffness ratio, rho = E(m)A(m)/E(f)A(f), have on stress redistribution. Comparisons with the Mode I plane orthotropic linear elasticity solution are favorable for both shear and axial tensile stresses. The best applications for such techniques are as numerical micromechanics tools in large-scale simulation codes of failure in fibrous composites. The present study is an important prerequisite for simulations and modeling of random fracture patterns, as would naturally develop in a real composite. Arbitrarily misaligned breaks are no more complicated to compute, and we reserve analyses of such cases to future simulation work involving random fiber strengths. (C) 1999 Elsevier Science Ltd. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Ctr Mat Sci, Los Alamos, NM 87545 USA. Univ Calif Santa Barbara, Dept Mech & Environm Engn, Santa Barbara, CA 93106 USA. RP Beyerlein, IJ (reprint author), Univ Calif Los Alamos Natl Lab, Ctr Mat Sci, Mail Stop G 755, Los Alamos, NM 87545 USA. RI Landis, Chad/B-6560-2008; Landis, Chad/C-9156-2013; Beyerlein, Irene/A-4676-2011 OI Landis, Chad/0000-0002-1330-3778; NR 36 TC 40 Z9 42 U1 6 U2 14 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-6636 J9 MECH MATER JI Mech. Mater. PD MAY PY 1999 VL 31 IS 5 BP 331 EP 350 DI 10.1016/S0167-6636(98)00075-1 PG 20 WC Materials Science, Multidisciplinary; Mechanics SC Materials Science; Mechanics GA 191QQ UT WOS:000080033400003 ER PT J AU Bohm, TD Deluca, PM Cox, LJ Maughan, RL Jones, DTL Lennox, A AF Bohm, TD Deluca, PM Cox, LJ Maughan, RL Jones, DTL Lennox, A TI Monte Carlo calculations to characterize the source for neutron therapy facilities SO MEDICAL PHYSICS LA English DT Article DE neutron therapy; neutrons; treatment planning; PEREGRINE; transport; MCNP; LAHET ID INTRANUCLEAR-CASCADE CALCULATION; SPECTRA; FLUENCE; BEAM AB Modern radiation treatment planning for photons includes full 3D modeling of the adsorbed dose distribution, accurate inclusion of the patient anatomy, and consideration of significant changes in material density and composition. Such efforts are founded in an accurate description of the radiation source and the beam delivery system. Modern fast neutron therapy facilities employ highly penetrating beams and isocentric beam delivery. Treatment planning is largely based on analytic models adapted from photon codes and interaction cross sections normalized to macroscopic attenuation. However, the recent PEREGRINE initiative at Lawrence Livermore Laboratory offers the possibility of fully stochastic modeling if the neutron source can be adequately described. In this article we report neutron source modeling of three high energy facilities. Neutron production is based on the intra-nuclear cascade model of the LAHET code while neutron transport through the beam delivery system is managed by MCNP using cross section libraries extended to 100 MeV neutron energy. PEREGRINE is then used to transport the neutron beam through typical phantoms. The resulting neutron sources are in excellent agreement with the limited experimental information and the measured phantom data are well described by the PEREGRINE transport using the LAHET/MCNP determined neutron sources. (C) 1999 American Association of Physicists in Medicine. [S0094-2405(99)02705-4]. C1 Univ Wisconsin, Dept Med Phys, Madison, WI 53706 USA. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Harper Grace Hosp, Gershenson Radiat Oncol Ctr, Detroit, MI 48201 USA. Wayne State Univ, Detroit, MI 48201 USA. Natl Accelerator Ctr, ZA-7131 Faure, South Africa. Fermilab Natl Accelerator Lab, Neutron Therapy Facil, Batavia, IL 60510 USA. RP Bohm, TD (reprint author), Univ Wisconsin, Dept Med Phys, Madison, WI 53706 USA. NR 19 TC 16 Z9 16 U1 0 U2 1 PU AMER ASSOC PHYSICISTS MEDICINE AMER INST PHYSICS PI MELVILLE PA STE 1 NO 1, 2 HUNTINGTON QUADRANGLE, MELVILLE, NY 11747-4502 USA SN 0094-2405 J9 MED PHYS JI Med. Phys. PD MAY PY 1999 VL 26 IS 5 BP 783 EP 792 DI 10.1118/1.598596 PG 10 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 196NQ UT WOS:000080314800019 PM 10360543 ER PT J AU Colonna, N Beaulieu, L Phair, L Wozniak, GJ Moretto, LG Chu, WT Ludewigt, BA AF Colonna, N Beaulieu, L Phair, L Wozniak, GJ Moretto, LG Chu, WT Ludewigt, BA TI Measurements of low-energy (d,n) reactions for BNCT SO MEDICAL PHYSICS LA English DT Article DE boron neutron capture therapy (BNCT); accelerator-based neutron source; neutron-producing reactions ID NEUTRON-CAPTURE THERAPY; ACCELERATOR; TARGET AB Neutron yields and energy spectra have been measured for various deuteron-induced reactions at low energy. Neutrons of energy >100 keV emitted in the Be-9(d,n)B-10, C-12(d,n)N-13, and C-13(d,n)N-14 reactions at E-d = 1.5 MeV were detected at five angles by means of liquid scintillator detectors. While low-energy neutrons were observed in all studied reactions, only C-13(d,n)N-14 is characterized by a relatively large yield with spectral features potentially interesting for an accelerator-based neutron source for BNCT. (C) 1999 American Association of Physicists in Medicine. [S0094-2405(99)02405-0]. C1 Ist Nazl Fis Nucl, I-70126 Bari, Italy. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, Berkeley, CA 94720 USA. RP Colonna, N (reprint author), Ist Nazl Fis Nucl, I-70126 Bari, Italy. RI Beaulieu, Luc/A-6803-2009 OI Beaulieu, Luc/0000-0003-0429-6366 NR 19 TC 19 Z9 20 U1 0 U2 5 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0094-2405 J9 MED PHYS JI Med. Phys. PD MAY PY 1999 VL 26 IS 5 BP 793 EP 798 DI 10.1118/1.598599 PG 6 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 196NQ UT WOS:000080314800020 PM 10360544 ER PT J AU Gray, GT Chen, SR Vecchio, KS AF Gray, GT Chen, SR Vecchio, KS TI Influence of grain size on the constitutive response and substructure evolution of MONEL 400 SO METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE LA English DT Article ID MECHANICAL THRESHOLD STRESS; STRAIN-RATE DEFORMATION; LOW-TEMPERATURE; PLASTIC-DEFORMATION; FLOW-STRESS; BEHAVIOR; FATIGUE; ALLOYS; COPPER; NICKEL AB The influence of grain size on the constitutive behavior (strain-rate and temperature dependence of the yield stress and strain hardening) and substructure evolution of MONEL 400 was investigated. Increasing the grain size from 9.5 to 202 mu m was seen to reduce the quasi-static yield strength from 290 to 115 MPa, while having a minimal effect on the work-hardening response. Increasing the strain rate from quasi-static to dynamic strain rates (3000 s(-1)) was seen to increase the yield and overall flow-stress levels, but has no effect on the strong grain-size dependency exhibited by this alloy. The persistent influence of grain size to large strains is inconsistent with previous d(-1/2) pileup grain-size modeling in the literature, which predicts convergence at large strains. Substructure evolution differences between the grain interiors and adjacent to grain boundaries supports differential defect storage processes which are consistent with previously published work-hardening d(-1) modeling arguments for grain size-dependent strengthening in polycrystals. The integration of grain-size dependency into constitutive modeling using the mechanical threshold stress (MTS) model is discussed. The MTS model is shown to provide a robust constitutive description capturing yielding, large-strain work hardening, and grain-size effects simultaneously. The MTS model is, additionally, shown to satisfactorily address the experimentally observed transients due to strain-rate or temperature-path dependency. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Calif San Diego, Dept Ames, La Jolla, CA 92093 USA. RP Gray, GT (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. RI Vecchio, Kenneth/F-6300-2011 OI Vecchio, Kenneth/0000-0003-0217-6803 NR 42 TC 37 Z9 37 U1 2 U2 12 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 USA SN 1073-5623 J9 METALL MATER TRANS A JI Metall. Mater. Trans. A-Phys. Metall. Mater. Sci. PD MAY PY 1999 VL 30 IS 5 BP 1235 EP 1247 DI 10.1007/s11661-999-0273-8 PG 13 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 192UQ UT WOS:000080098300008 ER PT J AU Stephens, JJ Frear, DR AF Stephens, JJ Frear, DR TI Time-dependent deformation behavior of near-eutectic 60Sn-40Pb solder SO METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE LA English DT Article ID PB; ALLOY; SUPERPLASTICITY; DIFFUSION; CREEP AB The compressive creep and stress-strain behavior of the near-eutectic 60Sn-40Pb solder alloy has been investigated over the temperature range of -55 degrees C to 125 degrees C. The total primary creep strain is a strong function of stress and temperature: at lower temperatures and high applied stresses (i.e., near the power-law breakdown regime), it is quite large, while it is much smaller at higher temperatures and lower applied stresses. The compressive minimum creep rate as a function of stress and temperature is fit well by the Garofalo sinh equation. A discussion of the effective stress exponent, n(eff), in the context of the Garofalo sinh equation is presented to understand trends in the creep data. The values of n(eff), for the applied stress levels studied, are found to range from 3.09 to 5.00 at 125 degrees C, while they have a range of 10.75 to 15.79 at -55 degrees C. These trends are consistent with the interpretation of climb-dominated creep at higher temperatures and plasticity-dominated power law breakdown behavior at the lower temperatures. The microstructural observations suggest that, at elevated temperatures, deformation occurs by relative displacement of eutectic colonies in the solder microstructure accompanied by extensive grain coarsening in the colony boundaries. At lower temperatures (<0 degrees C), deformation occurs by cell displacement with very limited coarsening and, at high stresses, is dominated by plastic deformation. The application of the Garofalo sinh equation to other data sets for creep of eutectic Sn-Pb solder is also discussed. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Stephens, JJ (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 34 TC 33 Z9 35 U1 0 U2 2 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 USA SN 1073-5623 J9 METALL MATER TRANS A JI Metall. Mater. Trans. A-Phys. Metall. Mater. Sci. PD MAY PY 1999 VL 30 IS 5 BP 1301 EP 1313 DI 10.1007/s11661-999-0279-2 PG 13 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 192UQ UT WOS:000080098300014 ER PT J AU Zhu, JH Liu, CT Pike, LM Liaw, PK AF Zhu, JH Liu, CT Pike, LM Liaw, PK TI A thermodynamic interpretation of the size-ratio limits for laves phase formation SO METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE LA English DT Article ID MECHANICAL-PROPERTIES; INTERMETALLIC COMPOUNDS; ALLOYS; ENTHALPIES C1 Univ Tennessee, Dept Mat Sci & Engn, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. Haynes Int, Kokomo, IN 46904 USA. RP Zhu, JH (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, POB 2008, Oak Ridge, TN 37831 USA. NR 37 TC 17 Z9 17 U1 0 U2 4 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 USA SN 1073-5623 J9 METALL MATER TRANS A JI Metall. Mater. Trans. A-Phys. Metall. Mater. Sci. PD MAY PY 1999 VL 30 IS 5 BP 1449 EP 1452 DI 10.1007/s11661-999-0292-5 PG 4 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 192UQ UT WOS:000080098300027 ER PT J AU Dypvik, H Attrep, M AF Dypvik, H Attrep, M TI Geochemical signals of the late Jurassic, marine Mjolnir impact SO METEORITICS & PLANETARY SCIENCE LA English DT Article ID CRETACEOUS-TERTIARY BOUNDARY; BARENTS SEA; METEORITE IMPACT; SEDIMENTS; IRIDIUM; ORIGIN; CRATER; CLAY; KUPFERSCHIEFER; MINERALIZATION AB Of the only seven submarine impact craters that have been found globally, the Mjolnir crater is one of the best preserved and retains crater and ejecta. Geochemical studies (organic pyrolysis using the Rock Eval technique and XRF analysis for major, minor, and trace elements) of the Institute for Petroleum Research (IKU) core 7430/10-U-01 that was taken from a drillhole located similar to 30 km north-northeast of the crater rim show gradual establishment of anoxic sea floor conditions through the late Jurassic. These poorly ventilated water conditions were overturned due to the Mjolnir impact event. Waves and currents transported impact glass (which is now partly weathered to smectite) into the depositional area where the drillhole is located. The succeeding crater collapse transported impact material (e.g., shocked quartz and Ir) from the crater rim and deeper levels to the core site. Normal marine depositional conditions were established a short time after the crater collapsed. C1 Univ Oslo, Dept Geol, N-0316 Oslo, Norway. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Dypvik, H (reprint author), Univ Oslo, Dept Geol, POB 1047, N-0316 Oslo, Norway. NR 51 TC 25 Z9 25 U1 0 U2 3 PU METEORITICAL SOC PI FAYETTEVILLE PA DEPT CHEMISTRY/BIOCHEMISTRY, UNIV ARKANSAS, FAYETTEVILLE, AR 72701 USA SN 0026-1114 J9 METEORIT PLANET SCI JI Meteorit. Planet. Sci. PD MAY PY 1999 VL 34 IS 3 BP 393 EP 406 PG 14 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 201AL UT WOS:000080572400012 ER PT J AU Stulen, RH AF Stulen, RH TI Progress in the development of extreme ultraviolet lithography exposure systems SO MICROELECTRONIC ENGINEERING LA English DT Article; Proceedings Paper CT International Conference on Micro- and Nanofabrication CY SEP 22-24, 1998 CL LEUVEN, BELGIUM AB Extreme Ultraviolet Lithography (EUV) is viewed by many as the logical extension of current optical lithography which will enable future generations of integrated circuits (ICs) to be printed with feature sizes of 100nm and below. With the completion of the research phase and demonstration of practical feasibility in 1996, this technology has moved into active development in the United States, Europe and Japan. The development is now focusing on manufacturing system designs for the 100nm generation and below of ICs. The fundamental approach of EUV is to achieve sub 100nm resolution by dramatically reducing the exposure wavelength, dawn to 13nm, and using all reflective, multilayer-coated imaging optics. The light source for these tools can be either a laser produced plasma or a synchrotron. The most common system architecture considered by most groups is one based on a ring field camera and a step and scan mask and wafer stage system, similar to what is used in today's optical scanners for 0.25micron and below. In the U.S. the development is being carried out in a partnership between an industrial consortium, called the EUV LLC (made up of AMD, Intel and Motorola) and a Virtual National Laboratory (made up of Lawrence Berkeley National Laboratory, Lawrence Livermore National Laboratory and Sandia National Laboratories). This paper will describe the essential elements of a practical EUV lithography tool and the performance trades between the various subsystems that are consistent with commercial throughput requirements. C1 Sandia Natl Labs, Livermore, CA 94550 USA. RP Stulen, RH (reprint author), Sandia Natl Labs, Livermore, CA 94550 USA. NR 3 TC 4 Z9 4 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-9317 J9 MICROELECTRON ENG JI Microelectron. Eng. PD MAY PY 1999 VL 46 IS 1-4 BP 19 EP 22 DI 10.1016/S0167-9317(99)00007-6 PG 4 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Optics; Physics, Applied SC Engineering; Science & Technology - Other Topics; Optics; Physics GA 207TU UT WOS:000080952500005 ER PT J AU Lee, Y Gough, RA King, TJ Ji, Q Leung, KN McGill, RA Ngo, VV Williams, MD Zahir, N AF Lee, Y Gough, RA King, TJ Ji, Q Leung, KN McGill, RA Ngo, VV Williams, MD Zahir, N TI Maskless ion beam lithography system SO MICROELECTRONIC ENGINEERING LA English DT Article; Proceedings Paper CT International Conference on Micro- and Nanofabrication CY SEP 22-24, 1998 CL LEUVEN, BELGIUM AB A new type of focused ion beam column is being designed to achieve a beam spot size of less than 100nm. This column is compact and can be operated with multiple beams to enhance the throughput for lithography applications. The column has been coupled with a multicusp ion source for beam transmission and high voltage holdup testing. The 2.5-cm long column can be used to accelerate different kinds of ion beams up to 45 keV. RP Lee, Y (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, 1 Cyclotron Rd,MS 5-121, Berkeley, CA 94720 USA. NR 5 TC 5 Z9 5 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-9317 J9 MICROELECTRON ENG JI Microelectron. Eng. PD MAY PY 1999 VL 46 IS 1-4 BP 469 EP 472 DI 10.1016/S0167-9317(99)00042-8 PG 4 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Optics; Physics, Applied SC Engineering; Science & Technology - Other Topics; Optics; Physics GA 207TU UT WOS:000080952500110 ER PT J AU Cole, EI Tangyunyong, P Barton, DL AF Cole, EI Tangyunyong, P Barton, DL TI Local thermal probing to detect open and shorted IC interconnections SO MICROELECTRONICS RELIABILITY LA English DT Article AB A new failure analysis technique has been developed for backside and frontside localization of open and shorted interconnections on ICs. This scanning optical microscopy technique lakes advantage of the interactions between IC defects and localized heating using a focused infrared laser (lambda = 1340 nm). Images are produced by monitoring the voltage changes across a constant current supply used to power the IC as the laser beam is scanned across the sample. The method utilizes the Seebeck Effect to localize open interconnections and Thermally-Induced Voltage Alteration to detect shorts. The interaction physics describing the signal generation process and several examples demonstrating the localization of opens and shorts are described. operational guidelines and limitations are also discussed. (C) 1999 Published by Elsevier Science Ltd. All rights reserved. C1 Sandia Natl Labs, Elect Qual Reliabil Ctr, Albuquerque, NM 87185 USA. RP Cole, EI (reprint author), Sandia Natl Labs, Elect Qual Reliabil Ctr, MS 1081, Albuquerque, NM 87185 USA. EM coleei@sandia.gov NR 14 TC 3 Z9 3 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0026-2714 J9 MICROELECTRON RELIAB JI Microelectron. Reliab. PD MAY PY 1999 VL 39 IS 5 BP 681 EP 693 DI 10.1016/S0026-2714(99)00016-5 PG 13 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA 231FE UT WOS:000082296800013 ER PT J AU Kurimasa, A Kumano, S Boubnov, NV Story, MD Tung, CS Peterson, SR Chen, DJ AF Kurimasa, A Kumano, S Boubnov, NV Story, MD Tung, CS Peterson, SR Chen, DJ TI Requirement for the kinase activity of human DNA-dependent protein kinase catalytic subunit in DNA strand break rejoining SO MOLECULAR AND CELLULAR BIOLOGY LA English DT Article ID ATAXIA-TELANGIECTASIA GENE; DEFICIENT CELL-LINES; V(D)J RECOMBINATION; SCID MOUSE; NONSENSE MUTATION; MAMMALIAN-CELLS; REPAIR MUTANTS; SIGNAL JOINT; END-BINDING; KU AB The catalytic subunit of DNA-dependent protein kinase (DNA-PKcs) is an enormous, 470-kDa protein serine/threonine kinase that has homology with members of the phosphatidylinositol (PI) 3-kinase superfamily. This protein contributes to the repair of DNA double-strand breaks (DSBs) by assembling broken ends of DNA molecules in combination with the DNA-binding factors Ku70 and Ku80. It may also serve as a molecular scaffold for recruiting DNA repair factors to DNA strand breaks. This study attempts to better define the role of protein kinase activity in the repair of DNA DSBs. We constructed a contiguous 14-kb human DNA-PKcs cDNA and demonstrated that it can complement the DNA DSB repair defects of two mutant cell lines known to be deficient in DNA-PKcs (M059J and V3). We then created deletion and site-directed mutations within the conserved PI 3-kinase domain of the DNA-PKcs gene to test the importance of protein kinase activity for DSB rejoining. These DNA-PKcs mutant constructs are able to express the protein but fail to complement the DNA DSB or V(D)J recombination defects of DNA-PKcs mutant cells. These results indicate that the protein kinase activity of DNA-PKcs is essential for the rejoining of DNA DSBs in mammalian cells. We have also determined a model structure for the DNA-PKcs kinase domain based on comparisons to the crystallographic structure of a cyclic AMP-dependent protein kinase. This structure gives some insight into which amino acid residues are crucial for the kinase activity in DNA-PKcs. C1 Univ Calif Los Alamos Natl Lab, Div Life Sci, DNA Damage & Repair Grp, Los Alamos, NM 87545 USA. Tottori Univ, Fac Med, Sch Life Sci, Yonago, Tottori 683, Japan. St Louis Univ, Dept Biochem & Mol Biol, St Louis, MO 63104 USA. Univ Texas, MD Anderson Canc Ctr, Dept Expt Radiotherapy, Houston, TX 77030 USA. RP Chen, DJ (reprint author), Univ Calif Los Alamos Natl Lab, Div Life Sci, DNA Damage & Repair Grp, MS-M888, Los Alamos, NM 87545 USA. FU NCI NIH HHS [CA06294, CA50519, P01 CA006294, R01 CA050519, R37 CA050519] NR 50 TC 200 Z9 203 U1 3 U2 5 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1325 MASSACHUSETTS AVENUE, NW, WASHINGTON, DC 20005-4171 USA SN 0270-7306 J9 MOL CELL BIOL JI Mol. Cell. Biol. PD MAY PY 1999 VL 19 IS 5 BP 3877 EP 3884 PG 8 WC Biochemistry & Molecular Biology; Cell Biology SC Biochemistry & Molecular Biology; Cell Biology GA 188AJ UT WOS:000079821100064 PM 10207111 ER PT J AU Eckert, J Stucky, GD Cheetham, AK AF Eckert, J Stucky, GD Cheetham, AK TI Partially disordered inorganic materials SO MRS BULLETIN LA English DT Article ID CARBOGENIC MOLECULAR-SIEVES; MESOPOROUS SILICA; DEFECT CHEMISTRY; MAGNETORESISTANCE; ZEOLITE; LAMNO3+/-DELTA; LAMNO3+DELTA; TEMPLATES; PHASES; SOLIDS C1 Univ Calif Los Alamos Natl Lab, Neutron Sci Ctr, Los Alamos, NM 87545 USA. Univ Calif Santa Barbara, Mat Res Lab, Santa Barbara, CA 93106 USA. RP Eckert, J (reprint author), Univ Calif Los Alamos Natl Lab, Neutron Sci Ctr, Los Alamos, NM 87545 USA. NR 47 TC 4 Z9 4 U1 0 U2 2 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DR, WARRENDALE, PA 15086 USA SN 0883-7694 J9 MRS BULL JI MRS Bull. PD MAY PY 1999 VL 24 IS 5 BP 31 EP 41 PG 11 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 197JE UT WOS:000080361000014 ER PT J AU Rawers, J Cook, D AF Rawers, J Cook, D TI Influence of attrition milling on nano-grain boundaries SO NANOSTRUCTURED MATERIALS LA English DT Article DE attrition milling; nanostructure; grain boundary ID RESOLUTION ELECTRON-MICROSCOPY; X-RAY-DIFFRACTION; HALL-PETCH RELATION; NANOCRYSTALLINE MATERIALS; NANOSTRUCTURED MATERIALS; IRON POWDERS; FE-N; NITROGEN; MICROSTRUCTURE; MOSSBAUER AB Nanostructured materials have a relatively large proportion of their atoms associated with the grain boundary and the method used to develop the nano-grains has a strong influence on the resulting grain boundary structure. In this study; attrition milling iron powders and blends of iron powders produced micron-size particles composed of nano-size grains. Mechanical cold-working powder resulted in dislocation generation; multiplication; and congealing that produced grain refinement. As the grain size approached nano-dimensions; dislocations were no longer sustained within the grain and once generated rapidly diffuse to the rain boundary. Dislocations on the grain boundary strained the local lattice structure which; as the grain size decreased; became the entire grain. Mechanical alloying of substitutional aluminium atoms into iron powder resulted in the aluminium atoms substituting for iron atoms in the grain boundary cells and providing a grain boundary structure similar to that of the iron powder processed in ar on. Attrition milling iron powder in nitrogen gas resulted in nitrogen atoms being adsorbed onto the particle surface. Continued mechanical milling infused the nitrogen atoms into interstitial lattice sites on the grain boundary which also contributed to expanding and straining the local lattice. Published by Elsevier Science Ltd. C1 US DOE, Albany Res Ctr, Albany, OR 97321 USA. Old Dominion Univ, Dept Phys, Norfolk, VA 23529 USA. RP Rawers, J (reprint author), US DOE, Albany Res Ctr, Albany, OR 97321 USA. NR 46 TC 44 Z9 46 U1 2 U2 4 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0965-9773 J9 NANOSTRUCT MATER JI Nanostruct. Mater. PD MAY PY 1999 VL 11 IS 3 BP 331 EP 342 DI 10.1016/S0965-9773(99)00049-5 PG 12 WC Materials Science, Multidisciplinary SC Materials Science GA 228VF UT WOS:000082155800006 ER PT J AU Hooker, BS Skeen, RS AF Hooker, BS Skeen, RS TI Transgenic phytoremediation blasts onto the scene SO NATURE BIOTECHNOLOGY LA English DT News Item ID PLANTS C1 Pacific NW Lab, Richland, WA 99352 USA. RP Hooker, BS (reprint author), Pacific NW Lab, POB 999, Richland, WA 99352 USA. NR 8 TC 20 Z9 20 U1 0 U2 0 PU NATURE AMERICA INC PI NEW YORK PA 345 PARK AVE SOUTH, NEW YORK, NY 10010-1707 USA SN 1087-0156 J9 NAT BIOTECHNOL JI Nat. Biotechnol. PD MAY PY 1999 VL 17 IS 5 BP 428 EP 428 DI 10.1038/8596 PG 1 WC Biotechnology & Applied Microbiology SC Biotechnology & Applied Microbiology GA 192JE UT WOS:000080074500019 PM 10331794 ER PT J AU Kobe, B Jennings, IG House, CM Michell, BJ Goodwill, KE Santarsiero, BD Stevens, RC Cotton, RGH Kemp, BE AF Kobe, B Jennings, IG House, CM Michell, BJ Goodwill, KE Santarsiero, BD Stevens, RC Cotton, RGH Kemp, BE TI Structural basis of autoregulation of phenylalanine hydroxylase SO NATURE STRUCTURAL BIOLOGY LA English DT Article ID AMINO-ACID HYDROXYLASES; CRYSTAL-STRUCTURE; DIFFRACTION DATA; PROTEIN; PHOSPHORYLATION; PHENYLKETONURIA; REFINEMENT; PROGRAM; DOMAIN; MODELS AB Phenylalanine hydroxylase converts phenylalanine to tyrosine, a rate-limiting step in phenylalanine catabolism and protein and neurotransmitter biosynthesis. It is tightly regulated by the substrates phenylalanine and tetrahydrobiopterin and by phosphorylation. We present the crystal structures of dephosphorylated and phosphorylated forms of a dimeric enzyme with catalytic and regulatory properties of the wild-type protein. The structures reveal a catalytic domain flexibly linked to a regulatory domain. The latter consists of an N-terminal autoregulatory sequence (containing Ser 16, which is the site of phosphorylation) that extends over the active site pocket, and an alpha-beta sandwich core that is, unexpectedly, structurally related to both pterin dehydratase and the regulatory domains of metabolic enzymes. Phosphorylation has no major structural effects in the absence of phenylalanine, suggesting that phenylalanine and phosphorylation act in concert to activate the enzyme through a combination of intrasteric and possibly allosteric mechanisms. C1 St Vincents Inst Med Res, Fitzroy, Vic 3065, Australia. Mutat Res Ctr, Fitzroy, Vic 3065, Australia. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. RP Kobe, B (reprint author), St Vincents Inst Med Res, 41 Victoria Parade, Fitzroy, Vic 3065, Australia. EM B.Kobe@medicine.unimelb.edu.au RI Kobe, Bostjan/D-1292-2009; Kemp, Bruce/L-2633-2014; Stevens, Raymond/K-7272-2015 OI Kobe, Bostjan/0000-0001-9413-9166; Kemp, Bruce/0000-0001-6735-5082; Stevens, Raymond/0000-0002-4522-8725 NR 30 TC 171 Z9 178 U1 2 U2 16 PU NATURE AMERICA INC PI NEW YORK PA 345 PARK AVE SOUTH, NEW YORK, NY 10010-1707 USA SN 1072-8368 J9 NAT STRUCT BIOL JI Nat. Struct. Biol. PD MAY PY 1999 VL 6 IS 5 BP 442 EP 448 DI 10.1038/8247 PG 7 WC Biochemistry & Molecular Biology; Biophysics; Cell Biology SC Biochemistry & Molecular Biology; Biophysics; Cell Biology GA 193JP UT WOS:000080132600015 PM 10331871 ER PT J AU Molina, PE Abumrad, NN AF Molina, PE Abumrad, NN TI Central sympathetic modulation of tissue cytokine response to hemorrhage SO NEUROIMMUNOMODULATION LA English DT Article DE shock; norepinephrine; sympathectomy; tumor necrosis factor-alpha; interleukin-6; 6-hydroxydopamine ID TUMOR-NECROSIS-FACTOR; NITRIC-OXIDE PRODUCTION; NERVOUS-SYSTEM; IN-VIVO; FACTOR-ALPHA; LIPOPOLYSACCHARIDE; MORPHINE; RELEASE; MICE; RAT AB Hemorrhage is associated with altered immune responses as well as with early increases in circulating levels and tissue content of proinflammatory cytokines, The present study determined the effects of central chemical sympathectomy on the early increase in tissue content of tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) following fixed-pressure (40 mm Hg) hemorrhage as well as on the associated activation of the opiate and glucocorticoid systems. Conscious unrestrained nonheparinized male Sprague-Dawley rats were randomized to receive either 6-hydroxydopamine intracerebroventricularly or equal volumes of saline (5 mu l). Half of the animals in each group underwent hemorrhage followed by fluid resuscitation with lactated Ringer's solution, and were sacrificed at completion of the resuscitation period. Hemorrhage elevated TNF-alpha and IL-6 content in spleen (30-47%) and lung (similar to 40%), Central chemical sympathectomy did not alter tissue cytokine content or circulating levels of beta-endorphin and corticosterone. However, central chemical sympathectomy attenuated the hemorrhage-induced increase in lung and spleen TNF-alpha enhanced the IL-6 response in spleen and blunted the rise in circulating beta-endorphin levels. These results demonstrate central modulation of the inflammatory and opiate responses to hemorrhagic stress. C1 N Shore Univ Hosp, Dept Surg, Manhasset, NY 11030 USA. Brookhaven Natl Lab, Dept Med, Div Surg Res, NSUH, Upton, NY 11973 USA. RP Molina, PE (reprint author), Brookhaven Natl Lab, Dept Med, Div Surg Res, NSUH, Bldg 490, Upton, NY 11973 USA. FU NIGMS NIH HHS [GM 50567] NR 46 TC 10 Z9 11 U1 0 U2 0 PU KARGER PI BASEL PA ALLSCHWILERSTRASSE 10, CH-4009 BASEL, SWITZERLAND SN 1021-7401 J9 NEUROIMMUNOMODULAT JI Neuroimmunomodulation PD MAY-JUN PY 1999 VL 6 IS 3 BP 193 EP 200 DI 10.1159/000026382 PG 8 WC Endocrinology & Metabolism; Immunology; Neurosciences SC Endocrinology & Metabolism; Immunology; Neurosciences & Neurology GA 190PZ UT WOS:000079974300007 PM 10213918 ER PT J AU Hodgson, JG Agopyan, N Gutekunst, CA Leavitt, BR LePiane, F Singaraja, R Smith, DJ Bissada, N McCutcheon, K Nasir, J Jamot, L Li, XJ Stevens, ME Rosemond, E Roder, JC Phillips, AG Rubin, EM Hersch, SM Hayden, MR AF Hodgson, JG Agopyan, N Gutekunst, CA Leavitt, BR LePiane, F Singaraja, R Smith, DJ Bissada, N McCutcheon, K Nasir, J Jamot, L Li, XJ Stevens, ME Rosemond, E Roder, JC Phillips, AG Rubin, EM Hersch, SM Hayden, MR TI A YAC mouse model for Huntington's disease with full-length mutant huntingtin, cytoplasmic toxicity, and selective striatal neurodegeneration SO NEURON LA English DT Article ID NEURONAL INTRANUCLEAR INCLUSIONS; TRANSGENIC MICE; NUCLEAR-LOCALIZATION; POSTSYNAPTIC CALCIUM; POLYGLUTAMINE TRACT; EMBRYONIC LETHALITY; GENE HOMOLOG; PROTEIN; BRAIN; POTENTIATION AB We have produced yeast artificial chromosome (YAC) transgenic mice expressing normal (YAC18) and mutant (YAC46 and YAC72) huntingtin (htt) in a developmental and tissue-specific manner identical to that observed in Huntington's disease (HD). YAC46 and YAC72 mice show early electrophysiological abnormalities, indicating cytoplasmic dysfunction prior to observed nuclear inclusions or neurodegeneration. By 12 months of age, YAC72 mice have a selective degeneration of medium spiny neurons in the lateral striatum associated with the translocation of N-terminal htt fragments to the nucleus. Neurodegeneration can be present in the absence of macro- or microaggregates, clearly showing that aggregates are not essential to initiation of neuronal death. These mice demonstrate that initial neuronal cytoplasmic toxicity is followed by cleavage of htt, nuclear translocation of htt N-terminal fragments, and selective neurodegeneration. C1 Univ British Columbia, Ctr Mol Med & Therapeut, Vancouver, BC V5Z 4H4, Canada. Univ British Columbia, Dept Psychol, Vancouver, BC V6T 1Z4, Canada. Univ Toronto, Fac Pharm, Toronto, ON L4V 1V7, Canada. Univ Toronto, Dept Mol Immunol & Neurobiol, Toronto, ON M5G 1X5, Canada. Emory Univ, Sch Med, Atlanta, GA 30322 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Human Genome, Berkeley, CA 94720 USA. RP Hayden, MR (reprint author), Univ British Columbia, Ctr Mol Med & Therapeut, Vancouver, BC V5Z 4H4, Canada. RI Leavitt, Blair/G-1934-2012; Roder, John/G-6468-2013; Hayden, Michael/D-8581-2011 OI Hayden, Michael/0000-0001-5159-1419 FU NINDS NIH HHS [NS36232, NS35255] NR 46 TC 563 Z9 578 U1 4 U2 28 PU CELL PRESS PI CAMBRIDGE PA 1050 MASSACHUSETTES AVE, CIRCULATION DEPT, CAMBRIDGE, MA 02138 USA SN 0896-6273 J9 NEURON JI Neuron PD MAY PY 1999 VL 23 IS 1 BP 181 EP 192 DI 10.1016/S0896-6273(00)80764-3 PG 12 WC Neurosciences SC Neurosciences & Neurology GA 202ZA UT WOS:000080681200021 PM 10402204 ER PT J AU Theofanous, TG Yuen, WW Angelini, S Sienicki, JJ Freeman, K Chen, X Salmassi, T AF Theofanous, TG Yuen, WW Angelini, S Sienicki, JJ Freeman, K Chen, X Salmassi, T TI Lower head integrity under steam explosion loads SO NUCLEAR ENGINEERING AND DESIGN LA English DT Article; Proceedings Paper CT Specialist Meeting on Nuclear Safety/International Seminar on Vapour Explosions and Explosive Eruptions CY MAY, 1997 CL SENDAI, JAPAN SP CSNI, Japan Atomic Energy Res Inst Tokai-mura, Minist Educ, Sports & Culture DE steam explosions; reactor safety; in-vessel retention; severe accident management ID CONTAINMENT FAILURE; TEMPERATURES AB Lower head integrity under steam explosion loads in an AP600-like reactor design is considered. The assessment is the second part of an evaluation of the in-vessel retention idea as a severe accident management concept, the first part (DOE/ID-10460) dealing with thermal loads. The assessment is conducted in terms of the risk oriented accident analysis methodology (ROAAM), and includes the comprehensive evaluation of all relevant severe accident scenarios, melt conditions and timing of release from the core region, fully three-dimensional mixing and explosion wave dynamics, and lower head fragility under local, dynamic loading. All of these factors are brought together in a ROAAM probabilistic framework to evaluate failure likelihood. The conclusion is that failure is 'physically unreasonable'. (C) 1999 Elsevier Science S.A. All rights reserved. C1 Univ Calif Santa Barbara, Ctr Risk Studies & Safety, Santa Barbara, CA 93106 USA. Argonne Natl Lab, Argonne, IL 60439 USA. RP Univ Calif Santa Barbara, Ctr Risk Studies & Safety, Santa Barbara, CA 93106 USA. EM theo@theo.ucsb.edu NR 36 TC 8 Z9 8 U1 0 U2 1 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0029-5493 EI 1872-759X J9 NUCL ENG DES JI Nucl. Eng. Des. PD MAY PY 1999 VL 189 IS 1-3 BP 7 EP 57 DI 10.1016/S0029-5493(99)00028-X PG 51 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 212PX UT WOS:000081226400004 ER PT J AU Bass, BR McAfee, WJ Williams, PT Pennell, WE AF Bass, BR McAfee, WJ Williams, PT Pennell, WE TI Fracture assessment of shallow-flaw cruciform beams tested under uniaxial and biaxial loading conditions SO NUCLEAR ENGINEERING AND DESIGN LA English DT Article ID STATISTICAL-ANALYSIS; MULTIAXIAL FRACTURE; CRITERION AB A technology to determine shallow-flaw fracture toughness of reactor pressure vessel (RPV) steels is being developed for application to the safety assessment of RPVs containing postulated shallow surface flaws. Matrices of cruciform beam tests were developed to investigate and quantify the effects of temperature, biaxial loading, and specimen size on fracture initiation toughness of two-dimensional (constant depth), shallow, surface flaws. The cruciform beam specimens were developed at Oak Ridge National Laboratory (ORNL) to introduce a far-field, out-of-plane biaxial stress component in the test section that approximates the nonlinear stresses resulting from pressurized-thermal-shock or pressure-temperature loading of an RPV. Tests were conducted under biaxial load ratios ranging from uniaxial to equibiaxial. These tests demonstrated that biaxial loading can have a pronounced effect on shallow-flaw fracture toughness in the lower transition temperature region for an RPV material. The cruciform fracture toughness data were used to evaluate fracture methodologies for predicting the observed effects of biaxial loading on shallow-flaw fracture toughness. Initial emphasis was placed on assessment of stress-based methodologies, namely, the J-Q formulation, the Dodds-Anderson toughness scaling model, and the Weibull approach. Applications of these methodologies based on the hydrostatic stress fracture criterion indicated an effect of loading-biaxiality on fracture toughness; the conventional maximum principal stress criterion indicated no effect. A three-parameter Weibull model based on the hydrostatic stress criterion is shown to correlate with the experimentally observed biaxial effect on cleavage fracture toughness by providing a scaling mechanism between uniaxial and biaxial loading states. (C) 1999 Elsevier Science S.A. All rights reserved. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Bass, BR (reprint author), Oak Ridge Natl Lab, POB 2009,Mail Stop 8056, Oak Ridge, TN 37831 USA. NR 31 TC 32 Z9 32 U1 2 U2 2 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0029-5493 J9 NUCL ENG DES JI Nucl. Eng. Des. PD MAY PY 1999 VL 188 IS 3 BP 259 EP 288 DI 10.1016/S0029-5493(99)00035-7 PG 30 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 205VM UT WOS:000080841300001 ER PT J AU Shah, VN Hookham, CJ AF Shah, VN Hookham, CJ TI Long-term aging of light water reactor concrete containments (vol 185, pg 51, 1998) SO NUCLEAR ENGINEERING AND DESIGN LA English DT Correction C1 Lockheed Martin Idaho Technol, Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. RP Shah, VN (reprint author), Lockheed Martin Idaho Technol, Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. NR 1 TC 0 Z9 0 U1 0 U2 3 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0029-5493 J9 NUCL ENG DES JI Nucl. Eng. Des. PD MAY PY 1999 VL 188 IS 3 BP 385 EP 385 DI 10.1016/S0029-5493(99)00087-4 PG 1 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 205VM UT WOS:000080841300011 ER PT J AU Maqueda, RJ Wurden, GA AF Maqueda, RJ Wurden, GA TI Fast imaging of visible phenomena in TFTR SO NUCLEAR FUSION LA English DT Article ID TOKAMAK; SYSTEM AB A commercial fast framing visible imaging system was used at TFTR to study edge plasma phenomena. This system was typically operated at 1000 frames/s, with exposures as short as 10 mu s. These short exposures ar made possible by the image intensification of the camera, which also allows narrow band interference filters to be used. Sequences of over 1600 digital images (239 pixel x 192 pixel x 8 bit) can be captured into temporary memory banks for later slow play-back and/or storage into computer archives. Examples are shown illustrating plasma disruption, flying debris, lithium pellet injection, shallow deposition of lithium by laser outside the plasma (DOLLOP) and edge plasma turbulence. The characteristics of this system make it also very useful to the machine operator, since they provide slow motion video coverage of the interior of the device. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87544 USA. RP Maqueda, RJ (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87544 USA. RI Wurden, Glen/A-1921-2017 OI Wurden, Glen/0000-0003-2991-1484 NR 11 TC 23 Z9 23 U1 0 U2 1 PU INT ATOMIC ENERGY AGENCY PI VIENNA PA WAGRAMERSTRASSE 5, PO BOX 100, A-1400 VIENNA, AUSTRIA SN 0029-5515 J9 NUCL FUSION JI Nucl. Fusion PD MAY PY 1999 VL 39 IS 5 BP 629 EP 636 DI 10.1088/0029-5515/39/5/305 PG 8 WC Physics, Fluids & Plasmas SC Physics GA 210VJ UT WOS:000081125100005 ER PT J AU Ford, R Jensen, DA Pushka, D Volk, J Zimmerman, ED AF Ford, R Jensen, DA Pushka, D Volk, J Zimmerman, ED TI A low cost, 400 G 18 '' (45.7 cm) gap C-magnet using permanent magnet technology SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article DE magnet; permanent; pandira; ferrite; dipole AB A low-cost, low-field (400 G) 18 " (45.7 cm) gap C-magnet using permanent magnets has been constructed. This magnet was used in a calibration study in the E799/E832 (KTeV) beamline at Fermilab. The C-magnet configuration was selected for ease of installation around an existing vacuum pipe. An advantage of the permanent magnet design is that no water or power connections are needed. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Chicago, Enrico Fermi Inst, Chicago, IL 60637 USA. RP Ford, R (reprint author), Fermi Natl Accelerator Lab, POB 500,MS 221, Batavia, IL 60510 USA. NR 5 TC 1 Z9 1 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD MAY 1 PY 1999 VL 426 IS 2-3 BP 238 EP 242 DI 10.1016/S0168-9002(98)01425-9 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 196JC UT WOS:000080304400002 ER PT J AU Moromisato, J von Goeler, E Reucroft, S Eartly, D Droege, T Prokofiev, D AF Moromisato, J von Goeler, E Reucroft, S Eartly, D Droege, T Prokofiev, D TI Study of position resolution with COPS SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article DE alignment; cross-hair laser; CCD arrays AB We describe an optical beam sensing device that can measure transverse displacements with accuracy of a few microns. An analog readout prototype with a set of four linear CCD arrays arranged around a square aperture, and illuminated by a cross-hair laser, was built and tested by the authors. Performance tests results demonstrate a linearity better than 5 mu m throughout an active transverse range of over 20 mm. The reproducibility of the measurements was better than 2 mu m. Long-term stability is 5 mu m. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Northeastern Univ, Dept Phys, Dana Res Ctr 111, Boston, MA 02115 USA. Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. RP Moromisato, J (reprint author), Northeastern Univ, Dept Phys, Dana Res Ctr 111, Boston, MA 02115 USA. NR 2 TC 1 Z9 1 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD MAY 1 PY 1999 VL 426 IS 2-3 BP 375 EP 384 DI 10.1016/S0168-9002(99)00054-6 PG 10 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 196JC UT WOS:000080304400012 ER PT J AU Assamagan, K Baker, K Bayatyan, G Carlini, R Danagoulian, S Eden, T Egiyan, K Ent, R Fenker, H Gan, L Gasparian, A Grigoryan, N Greenwood, Z Gueye, P Hashimoto, O Johnston, K Keppel, C Knyazyan, S Majewski, S Margaryan, A Margaryan, Y Marikyan, G Martoff, J Mkrtchyan, H Parlakyan, L Sato, Y Sawafta, R Simicevic, N Tadevosyan, V Takahashi, T Tang, L Vartanyan, G Vulcan, W Wells, S Wood, S AF Assamagan, K Baker, K Bayatyan, G Carlini, R Danagoulian, S Eden, T Egiyan, K Ent, R Fenker, H Gan, L Gasparian, A Grigoryan, N Greenwood, Z Gueye, P Hashimoto, O Johnston, K Keppel, C Knyazyan, S Majewski, S Margaryan, A Margaryan, Y Marikyan, G Martoff, J Mkrtchyan, H Parlakyan, L Sato, Y Sawafta, R Simicevic, N Tadevosyan, V Takahashi, T Tang, L Vartanyan, G Vulcan, W Wells, S Wood, S TI Time-zero fission-fragment detector based on low-pressure multiwire proportional chambers SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article ID MULTISTEP AVALANCHE CHAMBER; U-238; OPERATION; NUCLEI; MWPCS; IONS AB A time-zero fission fragment (FF) detector, based on the technique of low-pressure multiwire proportional chambers (LPMWPC), has been designed and constructed for the heavy hypernuclear lifetime experiment (E95-002) at Thomas Jefferson National Accelerator Facility. Its characteristics and the method of time-zero reconstruction were investigated using fission fragments from a Cf-252 spontaneous fission source. The influence of the ionization energy loss was also studied. It is shown that Heptane, Hexane, and Isobutane gases at a pressure of 1-2Torr are all suitable for such a FF detector. As desired by experiment, a timing resolution of about 200 ps (FWHM) for a chamber size of 21 x 21 cm(2) was achieved. (C) 1999 Published by Elsevier Science B.V. All rights reserved. C1 Yerevan Phys Inst, Yerevan 375036, Armenia. Hampton Univ, Hampton, VA 23668 USA. Thomas Jefferson Natl Accelerator Facil, Newport News, VA 23606 USA. Louisiana Tech Univ, Ruston, LA 71270 USA. Tohoku Univ, Sendai, Miyagi 98077, Japan. Temple Univ, Philadelphia, PA 19122 USA. N Carolina Agr & Technol State Univ, Greensboro, NC 27411 USA. RP Margaryan, A (reprint author), Yerevan Phys Inst, Yerevan 375036, Armenia. NR 35 TC 17 Z9 21 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 MAY 1 PY 1999 VL 426 IS 2-3 BP 405 EP 419 DI 10.1016/S0168-9002(98)01399-0 PG 15 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 196JC UT WOS:000080304400014 ER PT J AU Tudisco, S Amorini, F Cabibbo, M Cardella, G De Geronimo, G Di Pietro, A Fallica, G Figuera, P Musumarra, A Papa, M Pappalardo, G Rizzo, F Valvo, G AF Tudisco, S Amorini, F Cabibbo, M Cardella, G De Geronimo, G Di Pietro, A Fallica, G Figuera, P Musumarra, A Papa, M Pappalardo, G Rizzo, F Valvo, G TI A new large area monolithic silicon telescope SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article DE implanted silicon telescope; large capacitance preamplifier; charge discrimination; side effects ID DETECTOR TELESCOPE AB A new prototype of large area (20 x 20 mm(2)) monolithic silicon telescope with an ultrathin Delta E stage (1 Gun) has been built and tested. A particular mask for the ground electrode has been developed to improve the charge collection reducing the induction between the E and Delta E stages. A special designed preamplifier has been used for the readout of the signal from the Delta E stage to overcome the problem of the large input capacitance (40 nF). A rather low energy threshold charge discrimination has been obtained. Small side effects due to the electric field deformation near the ground electrode were observed and quantified. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Ist Nazl Fis Nucl, Sez Catania, I-95129 Catania, Italy. Ist Nazl Fis Nucl, Lab Nazl Sud, I-95126 Catania, Italy. Univ Catania, Dipartmento Fis, I-95129 Catania, Italy. Brookhaven Natl Lab, Instrumentat Div, Upton, NY 11973 USA. STMicroelectronics, I-95121 Catania, Italy. RP Cardella, G (reprint author), Ist Nazl Fis Nucl, Sez Catania, Corso Italia 57, I-95129 Catania, Italy. OI Tudisco, Salvatore/0000-0002-9390-9912 NR 9 TC 30 Z9 30 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 MAY 1 PY 1999 VL 426 IS 2-3 BP 436 EP 445 DI 10.1016/S0168-9002(98)01235-2 PG 10 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 196JC UT WOS:000080304400017 ER PT J AU Lopes, JAM dos Santos, JMF Conde, CAN Morgado, RE AF Lopes, JAM dos Santos, JMF Conde, CAN Morgado, RE TI A new integrated photosensor for gas proportional scintillation counters based on the gas electron multiplier (GEM) SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article DE scintillation counter; gas electron multiplier; photo electrons ID CSI-PHOTOCATHODE; DETECTORS; XENON AB The performance of a novel integrated photosensor for use in a xenon gas proportional scintillation detector is described. Earlier integrated photo-sensor designs were limited in charge gains due to the onset of electrical breakdown, which was ascribed to optical positive feedback from scintillation photons produced in the charge amplification stage. The present design uses a gas electron multiplier (GEM) composed of a 50 mu m thick Kapton film with copper-plated electrode surfaces on both sides and perforated with 200 mu m holes at a 300 mu m pitch. The front surface is made photosensitive with a 150-nm-thick CsI him. When an appropriate voltage is applied between the copper electrodes, the resulting electric field directs photoelectrons produced on the front surface through the holes in the GEM and onto a wire chamber where charge amplification occurs. Optical positive feedback is essentially eliminated since the charge amplification stage is optically de-coupled from the photocathode. The GEM also provides a small amount of charge gain, up to 3.3, before the electrons enter the wire chamber where charge gains up to about 10(3) take place. However, the measured effective quantum efficiency, namely, the number of photoelectrons traversing the GEM holes per incident 170 nm scintillation photon, as measured under present conditions, is only about 1%. A discussion of the results is presented. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Univ Coimbra, Dept Fis, P-3000 Coimbra, Portugal. Inst Super Engn Coimbra, P-3000 Coimbra, Portugal. Univ Calif Los Alamos Natl Lab, Los Alamos, NM USA. RP Conde, CAN (reprint author), Univ Coimbra, Dept Fis, P-3000 Coimbra, Portugal. RI matias-lopes, jose/H-6074-2012; dos Santos, Joaquim/B-3058-2015 OI matias-lopes, jose/0000-0002-6366-2963; NR 15 TC 14 Z9 15 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 MAY 1 PY 1999 VL 426 IS 2-3 BP 469 EP 476 DI 10.1016/S0168-9002(98)01419-3 PG 8 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 196JC UT WOS:000080304400021 ER PT J AU Sciolla, G AF Sciolla, G TI The BaBar drift chamber (vol 419, pg 310, 1998) SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Correction C1 Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Sciolla, G (reprint author), Stanford Linear Accelerator Ctr, POB 4349, Stanford, CA 94309 USA. NR 1 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 MAY 1 PY 1999 VL 426 IS 2-3 BP 646 EP 646 PG 1 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 196JC UT WOS:000080304400040 ER PT J AU Lee, EH AF Lee, EH TI Ion-beam modification of polymeric materials - fundamental principles and applications SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 3rd International Symposium on Ionizing Radiation and Polymers (IRaP 98) CY SEP 19-24, 1998 CL WEINBOHLA, GERMANY SP Inst Oberflachen Modifizier, Commissariat Energie Atom, Int Atomic Energy Agency, Gesell Schwerionenforsch, Deutsch Forsch Gemeinschaft, Sachsisches Minist Wissenschaft & Kultur DE ion-beam; LET effects; cross-linking; scission; tracks; spurs; hardness ID POLY(METHYL METHACRYLATE); RADIATION DEGRADATION; CHARGED-PARTICLES; IRRADIATION; HEAVY; WATER; EXPOSURE; SCISSION; PMMA AB When an energetic ion traverses a polymer medium, it loses its energy by electronic and nuclear processes. In the past, considerable research efforts have been devoted to understand the effects of the electronic and nuclear processes in materials. There have been, however, some conflicting reports regarding the roles of electronic and nuclear stopping in producing property changes in polymeric materials, namely the magnitude of cross-linking and scission. A consensus derived from the work conducted at ORNL indicates that electronic stopping is largely responsible for cross-linking and nuclear stopping for scission, although both processes can cause cross-linking as well as scission. The most important parameter for cross-linking is found to be the energy deposited per unit ion path length or linear energy transfer (LET). The mechanisms involved with property changes are discussed by clarifying the concepts of nuclear and electronic stopping, LET, tracks, and spurs. Experimental evidence to support the views are presented. Also addressed are specific property changes induced by ion-beams, which may be of use for industrial applications. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Lee, EH (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, POB 2008, Oak Ridge, TN 37831 USA. NR 46 TC 274 Z9 276 U1 1 U2 23 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1999 VL 151 IS 1-4 BP 29 EP 41 DI 10.1016/S0168-583X(99)00129-9 PG 13 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 201PN UT WOS:000080604100005 ER PT J AU Cooke, DW Muenchausen, RE Bennett, BL Orler, EB Wrobleski, DA Smith, ME Jahan, MS Thomas, DE AF Cooke, DW Muenchausen, RE Bennett, BL Orler, EB Wrobleski, DA Smith, ME Jahan, MS Thomas, DE TI Optical and magnetic resonance measurements of a segmented poly(ester urethane) SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 3rd International Symposium on Ionizing Radiation and Polymers (IRaP 98) CY SEP 19-24, 1998 CL WEINBOHLA, GERMANY SP Inst Oberflachen Modifizier, Commissariat Energie Atom, Int Atomic Energy Agency, Gesell Schwerionenforsch, Deutsch Forsch Gemeinschaft, Sachsisches Minist Wissenschaft & Kultur DE luminescence; optical absorption; ESR; polyurethane; polymer; triplet state AB X-ray-induced damage in Estane(R)5703 has been studied by luminescence, optical absorption and electron spin resonance techniques in the temperature interval approximate to 10-300 K. Molecular motion of the polymer soft segment, as determined by viscoelastic measurements, is correlated with features in the glow curve, indicating charge detrapping via thermal destruction of cavity traps. Spectral emission is characterized by four Lorentzian bands with maxima at 2.38, 2.55, 2.74 and 2.93 eV, which are attributed to triplet-to-singlet (pi, pi*) electronic transitions of the phenyl group in the polymer hard segment. Absorption peaks at 3.97, 4.29 and 4.46 eV are also assigned to transitions within this group. Several radicals with overlapping resonances are induced at 35 K, which, with increasing temperature, evolve into the relatively stable peroxy free-radical at room temperature. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Memphis, Memphis, TN 38152 USA. RP Cooke, DW (reprint author), Univ Calif Los Alamos Natl Lab, MST-8,MS E546, Los Alamos, NM 87545 USA. NR 7 TC 3 Z9 3 U1 1 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1999 VL 151 IS 1-4 BP 186 EP 189 DI 10.1016/S0168-583X(99)00087-7 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 201PN UT WOS:000080604100026 ER PT J AU Firouzbakht, ML Schlyer, DJ Wolf, AP Fowler, JS AF Firouzbakht, ML Schlyer, DJ Wolf, AP Fowler, JS TI Mechanism of nitrogen-13-labeled ammonia formation in a cryogenic water target SO NUCLEAR MEDICINE AND BIOLOGY LA English DT Article DE N-13 ammonia; positron-emitting isotopes; cryogenic targets ID RECOIL N-13 ATOMS; PROTON IRRADIATION; F-18 FLUORIDE; ACCELERATORS AB Methods for producing N-13 ammonia via the O-16(p,alpha)N-13 nuclear reaction utilizing a cryogenic target have been investigated. These targets included frozen carbon dioxide and pure frozen water. Results from these targets were compared with the more traditional liquid water target with and without additives. A very dramatic difference was found between the pure water target in the frozen state when compared with the liquid state. When frozen, more than 95% of the nitrogen-13 activity is in the chemical form of ammonia at all radiation doses. In contrast, the liquid water target yielded predominately nitrates and nitrites at high radiation doses. When frozen carbon dioxide was irradiated under these conditions, more than 95% of the nitrogen-13 activity was in the form of nitrate and nitrite. The nitrogen oxides remained on the surface of the target and could be easily removed from the surface with pure water. The wash solution was converted to [N-13]ammonia using the DeVarda's alloy method for reduction. It was determined that levels of [N-13]ammonia sufficient for diagnostic medical procedures could be produced directly using the frozen water targets or from frozen carbon dioxide with a wet chemical reduction. These results have significance particularly in the design of targetry for low-energy, high-beam current accelerators, because targets of this design can be used with either no vacuum isolation window or a very thin window. The substitution of carbon-13-enriched carbon dioxide for natural carbon dioxide gives access to the C-13(p,n)N-13 nuclear reaction, which allows protons energies as low as 6 MeV to be used to produce useable quantities of N-13 ammonia. The mechanism of these reactions has been explored to determine why there are such dramatic differences in the product distribution between the frozen state and the liquid or gaseous state. NUCL MED BIOL 26;4:437-441, 1999. (C) 1999 Elsevier Science Inc. All rights reserved. C1 Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. RP Schlyer, DJ (reprint author), Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. FU NINDS NIH HHS [NS 15380] NR 29 TC 1 Z9 1 U1 0 U2 0 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0969-8051 J9 NUCL MED BIOL JI Nucl. Med. Biol. PD MAY PY 1999 VL 26 IS 4 BP 437 EP 441 DI 10.1016/S0969-8051(99)00002-5 PG 5 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 196JE UT WOS:000080304600014 PM 10382848 ER PT J AU Ferrieri, RA Garcia, I Fowler, JS Wolf, AP AF Ferrieri, RA Garcia, I Fowler, JS Wolf, AP TI Investigations of acetonitrile solvent cluster formation in supercritical carbon dioxide, and its impact on microscale syntheses of carbon-11-labeled radiotracers for PET SO NUCLEAR MEDICINE AND BIOLOGY LA English DT Article DE supercritical fluids; [C-11]methyl iodide; solvent cage ID DIFFUSION-CONTROLLED REACTIONS; ABSOLUTE RATE CONSTANTS; TIME-RESOLVED ESR; PHASE-EQUILIBRIA; FLUID CHROMATOGRAPHY; SIMULTANEOUS EXTRACTION; MOLECULAR-DYNAMICS; RADICAL PAIRS; MIXTURES; PHOTOLYSIS AB A new strategy has been developed for synthesizing positron emission tomography (PET) radiotracers using [C-11]methyl iodide. This strategy relies on the ability of organic co-solvents to cluster within mixtures of supercritical fluids resulting in localized regions of high density which can serve as microscopic pockets for reaction. We've shown that acetonitrile will cluster about dilute solutes when mixtures of this co-solvent with carbon dioxide are forced to behave as a homogeneous fluid at the critical point. We applied this strategy in a systematic investigation of the conditions for optimized reaction between methyl iodide and L-alpha-methyl-N-2-propynyl phenethylamine (nordeprenyl) to yield L-deprenyl. Variables such as temperature, ultraviolet light exposure, co-solvent concentration, system pressure, and methyl iodide concentration were explored. The synthesis of radioactive [C-11]-L-deprenyl using no carrier added concen trations of [C-11]methyl iodide was also tested. Results showed that greater than 90% radiochemical yield of the desired product could be attained using 40 times less labeling substrate than in conventional PET tracer syntheses. NUCL MED BIOL 26;4:443-4154, 1999. (C) 1999 Elsevier Science Inc. All rights reserved. C1 Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. RP Ferrieri, RA (reprint author), Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. EM rferrieri@bnl.gov FU NINDS NIH HHS [NS-15380] NR 56 TC 7 Z9 7 U1 1 U2 2 PU ELSEVIER SCIENCE INC PI NEW YORK PA 360 PARK AVE SOUTH, NEW YORK, NY 10010-1710 USA SN 0969-8051 EI 1872-9614 J9 NUCL MED BIOL JI Nucl. Med. Biol. PD MAY PY 1999 VL 26 IS 4 BP 443 EP 454 DI 10.1016/S0969-8051(99)00011-6 PG 12 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 196JE UT WOS:000080304600015 PM 10382849 ER PT J AU Lin, WY Hsieh, JF Lin, CP Hsieh, BT Ting, G Wang, SJ Knapp, FF AF Lin, WY Hsieh, JF Lin, CP Hsieh, BT Ting, G Wang, SJ Knapp, FF TI Effect of reaction conditions on preparations of Rhenium-188 hydroxyethylidene diphosphonate complexes SO NUCLEAR MEDICINE AND BIOLOGY LA English DT Article DE rhenium-186; Re-188HEDP complexes; carrier ID PAINFUL OSSEOUS METASTASES; W-188/RE-188 GENERATORS; RADIONUCLIDES; THERAPY; RE-188; SR-89 AB Rhenium-186 (Re-186) hydroxyethylidene diphosphonate (HEDP) has been shown to localize in metastatic foci within bone in a manner similar to Tc-99m bone seeking agents. Usually, in the preparation of diagnostic Tc-99m radiopharmaceuticals, the concentration of Tc is at trace level (10(-8) M). However, large amounts of carrier are included in the preparation of Re-186 radiopharmaceuticals (10(-4) M), which may significantly affect the preparation of Re-HEDP. In this study, Re-188 was used as an Re tracer. The effects of pH and concentrations of Re carrier on the preparation of Re-HEDP were investigated. Re-188-Sn-HEDP was prepared by reconstitution of a kit of lyophilized HEDP mixture, and tin chloride with a radioactive solution of perrhenate in saline. The total concentration of Re present in this work ranged from 10(-8) to 10(-3) M. The results showed that high labeling efficiency was obtained for each preparation, Although the chemical behaviors of the Re-188 HEDP complexes, with and without carrier, were similar, the biodistribution patterns of carrier free Re-188 HEDP in rats were found to differ from the biodistribution patterns of carrier-added Re-188 HEDP. NUCL MED BIOL 26;4:455-459, 1999. (C) 1999 Elsevier Science Inc. All rights reserved. C1 Taichung Vet Gen Hosp, Dept Nucl Med, Taichung 40704, Taiwan. Chi Mei Fdn Hosp, Tainan, Taiwan. Natl Tsing Hua Univ, Dept Nucl Sci, Hsinchu, Taiwan. Inst Nucl Energy Res, Lungtan 32500, Taiwan. Oak Ridge Natl Lab, Nucl Med Grp, Oak Ridge, TN USA. RP Lin, WY (reprint author), Taichung Vet Gen Hosp, Dept Nucl Med, 160 Sec 3,Taichung Harbor Rd, Taichung 40704, Taiwan. NR 18 TC 31 Z9 34 U1 0 U2 0 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0969-8051 J9 NUCL MED BIOL JI Nucl. Med. Biol. PD MAY PY 1999 VL 26 IS 4 BP 455 EP 459 DI 10.1016/S0969-8051(99)00007-4 PG 5 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA 196JE UT WOS:000080304600016 PM 10382850 ER PT J AU Gavrin, VN AF Gavrin, VN CA SAGE Collaboration TI Solar neutrino results from SAGE SO NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS LA English DT Article; Proceedings Paper CT 18th International Conference on Neutrino Physics and Astrophysics (Neutrino 98) CY JUN 04-09, 1998 CL TAKAYAMA, JAPAN SP Int Union Pure & Appl Phys & Sci Council Japan ID DETECTOR AB We report the status of the Russian-American Gallium solar neutrino Experiment (SAGE). The solar neutrino result for SAGE III, 20 runs during the measuring period May 1995 through December 1997, is 56.7 +9.3 /-8.7(stat.)+4.6/-4.8(syst.) SNU. The combined result for 57 measurements from 1990 through 1997 (SAGE I+II+III) is 66.9 +7.1/-6.8 (stat) +5.4/-5.7 (syst) SNU. The final result of the SAGE Cr-51 experiment to check the response of SAGE to low energy neutrinos is also presented. C1 Russian Acad Sci, Inst Nucl Res, Moscow 117312, Russia. Los Alamos Natl Lab, Los Alamos, NM USA. Louisiana State Univ, Baton Rouge, LA 70803 USA. Univ Penn, Philadelphia, PA 19104 USA. Univ Washington, Seattle, WA 98195 USA. RP Russian Acad Sci, Inst Nucl Res, Moscow 117312, Russia. RI Abdurashitov, Dzhonrid/B-2206-2014 OI Abdurashitov, Dzhonrid/0000-0002-1577-1364 NR 17 TC 18 Z9 19 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-5632 EI 1873-3832 J9 NUCL PHYS B-PROC SUP JI Nucl. Phys. B-Proc. Suppl. PD MAY PY 1999 VL 77 BP 20 EP 25 DI 10.1016/S0920-5632(99)00385-0 PG 6 WC Physics, Particles & Fields SC Physics GA 217KD UT WOS:000081497700004 ER PT J AU White, DH AF White, DH CA LSND Collaboration TI Neutrino oscillation results from LSND SO NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS LA English DT Article; Proceedings Paper CT 18th International Conference on Neutrino Physics and Astrophysics (Neutrino 98) CY JUN 04-09, 1998 CL TAKAYAMA, JAPAN SP Int Union Pure & Appl Phys & Sci Council Japan ID SEARCH; BEAM; ISIS AB The LSND experiment at Los Alamos has conducted a search for (v) over bar(mu) --> (v) over bar(e) oscillations using (v) over bar(mu) from mu(+) decay at rest. The (v) over bar(e) are detected via the reaction (v) over bar(e) p --> e(+) n, correlated with the 2.2 MeV gamma from np --> d gamma. The use of tight cuts to identify e+ events with correlated gamma rays yielded 22 events with e(+) energy between 36 and 60 MeV and only 4.6 +/- 0.6 background events. The probability that this excess is due entirely to a statistical fluctuation is 4.1 x 10(-8). A chi(2) fit to the entire e+ sample results in a total excess of 51.8(-16.9)(+18.7) +/- 8.0 events with e(+) energy between 20 and 60 MeV. If attributed to (v) over bar(mu) --> (v) over bar(e) oscillations, this corresponds to an oscillation probability (averaged over the experimental energy and spatial acceptance) of 0.31 +/- 0.12 +/- 0.05. C1 Univ Calif Los Alamos Natl Lab, Div Phys, Los Alamos, NM 87545 USA. RP White, DH (reprint author), Univ Calif Los Alamos Natl Lab, Div Phys, Mail Stop H846, Los Alamos, NM 87545 USA. NR 13 TC 14 Z9 14 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-5632 J9 NUCL PHYS B-PROC SUP JI Nucl. Phys. B-Proc. Suppl. PD MAY PY 1999 VL 77 BP 207 EP 211 PG 5 WC Physics, Particles & Fields SC Physics GA 217KD UT WOS:000081497700030 ER PT J AU Bernstein, RH Adams, T Alton, A Avvakumov, S de Barbaro, L de Barbaro, P Bodek, A Bolton, T Brau, J Buchholz, D Budd, H Bugel, L Conrad, J Drucker, RB Frey, R Goldman, J Goncharov, M Harris, DA Johnson, RA Koutsoliotas, S Kim, JH Lamm, MJ Marsh, W Mason, D McFarland, KS McNulty, C Naples, D Nienaber, P Romosan, A Sakumoto, WK Schellman, H Shaevitz, MH Spentzouris, P Stern, EG Vakili, M Vaitaitis, A Wu, V Yang, UK Yu, J Zeller, GP AF Bernstein, RH Adams, T Alton, A Avvakumov, S de Barbaro, L de Barbaro, P Bodek, A Bolton, T Brau, J Buchholz, D Budd, H Bugel, L Conrad, J Drucker, RB Frey, R Goldman, J Goncharov, M Harris, DA Johnson, RA Koutsoliotas, S Kim, JH Lamm, MJ Marsh, W Mason, D McFarland, KS McNulty, C Naples, D Nienaber, P Romosan, A Sakumoto, WK Schellman, H Shaevitz, MH Spentzouris, P Stern, EG Vakili, M Vaitaitis, A Wu, V Yang, UK Yu, J Zeller, GP TI Determination of sin(2) theta(w) from neutrino-nucleon scattering at NuTeV SO NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS LA English DT Article; Proceedings Paper CT 18th International Conference on Neutrino Physics and Astrophysics (Neutrino 98) CY JUN 04-09, 1998 CL TAKAYAMA, JAPAN SP Int Union Pure & Appl Phys & Sci Council Japan ID PRECISION-MEASUREMENT; SEA AB Wk report the determination of sin(2) theta(W) in nu - N deep inelastic scattering from the NuTeV experiment. Using separate neutrino and anti-neutrino beams, NuTeV is able to extract sin2 Bw with low systematic errors from the Paschos-Wolfenstein variable R-, a ratio of differences of neutrino and antineutrino neutral-current and charged-current cross-sections. NuTeV measures sin(2) theta(W)((on-shell)) = 0.2253 +/- 0.0019(stat) +/- 0.0010(syst), which implies M-W = 80.26 +/- 0.11 GeV. C1 Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Cincinnati, Cincinnati, OH 45221 USA. Columbia Univ, New York, NY 10027 USA. Kansas State Univ, Manhattan, KS 66506 USA. Northwestern Univ, Evanston, IL 60208 USA. Univ Oregon, Eugene, OR 97403 USA. Univ Rochester, Rochester, NY 14627 USA. RP Bernstein, RH (reprint author), Fermi Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. RI Frey, Raymond/E-2830-2016; OI Frey, Raymond/0000-0003-0341-2636; Bernstein, Robert/0000-0002-7610-950X NR 18 TC 0 Z9 0 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-5632 J9 NUCL PHYS B-PROC SUP JI Nucl. Phys. B-Proc. Suppl. PD MAY PY 1999 VL 77 BP 265 EP 270 DI 10.1016/S0920-5632(99)00426-0 PG 6 WC Physics, Particles & Fields SC Physics GA 217KD UT WOS:000081497700037 ER PT J AU Spentzouris, P AF Spentzouris, P TI Neutrino physics with a muon collider SO NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS LA English DT Article; Proceedings Paper CT 18th International Conference on Neutrino Physics and Astrophysics (Neutrino 98) CY JUN 04-09, 1998 CL TAKAYAMA, JAPAN SP Int Union Pure & Appl Phys & Sci Council Japan ID OSCILLATIONS; SEARCH AB In the last few years, the idea of a muon accelerator complex has been actively pursued as an option for the next generation lepton collider. The very intense muon source (similar to 10(21) / per year) required for the collider, could provide very intense neutrino beams from muon decay in flight. The neutrino sources could either be the straight sections of the accelerator and the collider ring or a dedicated muon storage ring. In this note I discuss the physics potential of such neutrino sources for neutrino oscillations and Deep Inelastic Scattering measurements. C1 Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. RP Spentzouris, P (reprint author), Fermi Natl Accelerator Lab, POB 500, Batavia, IL 60510 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 0920-5632 J9 NUCL PHYS B-PROC SUP JI Nucl. Phys. B-Proc. Suppl. PD MAY PY 1999 VL 77 BP 276 EP 284 DI 10.1016/S0920-5632(99)00428-4 PG 9 WC Physics, Particles & Fields SC Physics GA 217KD UT WOS:000081497700039 ER PT J AU Albright, CH Babu, KS Barr, SM AF Albright, CH Babu, KS Barr, SM TI Implications of a minimal SO(10) Higgs structure SO NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS LA English DT Article; Proceedings Paper CT 18th International Conference on Neutrino Physics and Astrophysics (Neutrino 98) CY JUN 04-09, 1998 CL TAKAYAMA, JAPAN SP Int Union Pure & Appl Phys & Sci Council Japan ID NEUTRINO; RATIO; FLUX AB A minimal SO(10) Higgs structure involving a single adjoint field along with spinors, vectors and singlets has been shown to break the SO(10) gauge symmetry to the standard model while stabilizing the F-flat directions and solving the doublet-triplet splitting problem naturally. With this minimal set of Higgs fields, we show how to construct quark and lepton mass matrices which explain well the many features of the observed spectrum, including the Georgi-Jarlskog mass relations. A large nu(mu) - nu(tau) mixing angle results naturally as observed in the atmospheric neutrino data. A particular model relying on a family symmetry has been constructed which realizes the desired mass matrices. C1 No Illinois Univ, Dept Phys, De Kalb, IL 60115 USA. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Inst Adv Study, Sch Nat Sci, Princeton, NJ 08540 USA. Univ Delaware, Bartol Res Inst, Newark, DE 19716 USA. RP No Illinois Univ, Dept Phys, De Kalb, IL 60115 USA. OI Albright, Carl/0000-0002-2252-6359 NR 18 TC 7 Z9 7 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-5632 EI 1873-3832 J9 NUCL PHYS B-PROC SUP JI Nucl. Phys. B-Proc. Suppl. PD MAY PY 1999 VL 77 BP 308 EP 312 DI 10.1016/S0920-5632(99)00433-8 PG 5 WC Physics, Particles & Fields SC Physics GA 217KD UT WOS:000081497700043 ER PT J AU Sadoulet, B AF Sadoulet, B TI Direct searches for dark matter SO NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS LA English DT Article; Proceedings Paper CT 18th International Conference on Neutrino Physics and Astrophysics (Neutrino 98) CY JUN 04-09, 1998 CL TAKAYAMA, JAPAN SP Int Union Pure & Appl Phys & Sci Council Japan ID COLD PLUS HOT; DOUBLE-BETA; COSMOLOGICAL PARAMETERS; COSMIC AXIONS; GRAN-SASSO; LIMITS; CANDIDATES; DETECTOR; UNIVERSE; MASS AB After briefly recalling the evidence which suggests that the dark matter pervading the universe is nonbaryonic, we review the present searches for the best motivated particle candidates: axions, light neutrinos and Weakly Interacting Massive Particles (WIMPs). C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Particle Astrophys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. RP Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Particle Astrophys, Berkeley, CA 94720 USA. NR 81 TC 6 Z9 6 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-5632 EI 1873-3832 J9 NUCL PHYS B-PROC SUP JI Nucl. Phys. B-Proc. Suppl. PD MAY PY 1999 VL 77 BP 389 EP 397 DI 10.1016/S0920-5632(99)00448-X PG 9 WC Physics, Particles & Fields SC Physics GA 217KD UT WOS:000081497700053 ER PT J AU Dalhed, HE Wilson, JR Mayle, RW AF Dalhed, HE Wilson, JR Mayle, RW TI Supernova neutrinos: Review SO NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS LA English DT Article; Proceedings Paper CT 18th International Conference on Neutrino Physics and Astrophysics (Neutrino 98) CY JUN 04-09, 1998 CL TAKAYAMA, JAPAN SP Int Union Pure & Appl Phys & Sci Council Japan AB This review discusses the role of neutrinos in the dynamics of supernovae. Neutrinos not only provide an essential probe into the core collapse mechanism, but also probably play an active role in the explosion mechanism. The time history of the neutrino fluences and their spectral shapes are affected by such physics as the nuclear equation of state and convection modeling. In turn, neutrinos play an active role in depositing energy in the region behind the outgoing shock wave and in the potential formation of heavy nuclei via r-process nucleosynthesis. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Dalhed, HE (reprint author), Univ Calif Lawrence Livermore Natl Lab, 7000 East Ave,Mail Stop L-015, Livermore, CA 94550 USA. NR 7 TC 3 Z9 3 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-5632 J9 NUCL PHYS B-PROC SUP JI Nucl. Phys. B-Proc. Suppl. PD MAY PY 1999 VL 77 BP 429 EP 434 PG 6 WC Physics, Particles & Fields SC Physics GA 217KD UT WOS:000081497700057 ER PT J AU Kiers, K Tytgat, MHG AF Kiers, K Tytgat, MHG TI The neutrino ground state in a neutron star SO NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS LA English DT Article; Proceedings Paper CT 18th International Conference on Neutrino Physics and Astrophysics (Neutrino 98) CY JUN 04-09, 1998 CL TAKAYAMA, JAPAN SP Int Union Pure & Appl Phys & Sci Council Japan ID OSCILLATIONS; MATTER; SPECTROSCOPY AB We address a recent claim that the stability of neutron stars implies a lower bound on the mass of the neutrino. We argue that the result obtained by some previous authors is due to an improper summation of an infrared-sensitive series and that a non-perturbative "resummation" of the series yields a finite and well-behaved result. The stability of neutron stars thus gives no lower bound on the mass of the neutrino. C1 Taylor Univ, Dept Phys, Upland, IN 46989 USA. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Free Univ Brussels, Serv Phys Theor, B-1050 Brussels, Belgium. RP Kiers, K (reprint author), Taylor Univ, Dept Phys, 236 W Reade Ave, Upland, IN 46989 USA. NR 18 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-5632 J9 NUCL PHYS B-PROC SUP JI Nucl. Phys. B-Proc. Suppl. PD MAY PY 1999 VL 77 BP 445 EP 449 DI 10.1016/S0920-5632(99)00464-8 PG 5 WC Physics, Particles & Fields SC Physics GA 217KD UT WOS:000081497700060 ER PT J AU Murayama, H AF Murayama, H TI Neutrino mass and baryon asymmetry SO NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS LA English DT Article; Proceedings Paper CT 18th International Conference on Neutrino Physics and Astrophysics (Neutrino 98) CY JUN 04-09, 1998 CL TAKAYAMA, JAPAN SP Int Union Pure & Appl Phys & Sci Council Japan AB The atmospheric neutrino data reported at this meeting strongly suggests neutrino oscillation, while the situation with the solar neutrino data is becoming more and more convincing as well. Both suggest tiny but finite neutrino masses. I first review why such neutrino masses are closely related to baryon-number violation in the early Universe. I also present a simple scheme of baryogensis, the Minimal Supersymmetric Leptogenesis, which generates the baryon asymmetry of desired order of magnitude with the mass range suggested by atmospheric and solar neutrino data, but not with the Hot Dark: Matter (HDM) mass range. Finally I point out a dark horse HDM candidate (hadronic axion) which may be testable by SuperKamiokande with a galactic supernova. C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Theoret Phys Grp, Berkeley, CA 94720 USA. RP Murayama, H (reprint author), Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. RI Murayama, Hitoshi/A-4286-2011 NR 4 TC 1 Z9 1 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-5632 J9 NUCL PHYS B-PROC SUP JI Nucl. Phys. B-Proc. Suppl. PD MAY PY 1999 VL 77 BP 450 EP 455 DI 10.1016/S0920-5632(99)00466-1 PG 6 WC Physics, Particles & Fields SC Physics GA 217KD UT WOS:000081497700061 ER PT J AU Andres, EC Askebjer, P Barwick, SW Bay, RC Bergstrom, L Biron, A Booth, J Botner, O Bouchta, A Carius, S Carlson, M Chinowsky, W Chirkin, D Conrad, J Costa, CGS Cowen, D Dalberg, E DeYoung, T Edsjo, J Ekstrom, P Goobar, A Gray, L Hallgren, A Halzen, F Hardtke, R Hart, S He, Y de los Heros, CP Hill, G Hulth, PO Hundertmark, S Jacobsen, J Jones, A Kandhadai, V Karle, A Kim, J Leich, H Leuthold, M Lindahl, P Liubarsky, I Loaiza, P Lowder, D Marciniewski, P Miller, TC Miocinovic, P Mock, PC Morse, R Newcomer, M Niessen, P Nygren, D Porrata, R Potter, D Price, PB Przybylski, G Rhode, W Richter, S Rodriguez, J Romenesko, P Ross, D Rubinstein, H Schmidt, T Schneider, E Schwarz, R Schwendicke, U Smoot, G Solarz, M Sorin, V Spiering, C Steffen, P Stokstad, R Streicher, O Taboada, I Thon, T Tilav, S Walck, C Wiebusch, CH Wischnewski, R Woschnagg, K Wu, W Yodh, G Young, S AF Andres, EC Askebjer, P Barwick, SW Bay, RC Bergstrom, L Biron, A Booth, J Botner, O Bouchta, A Carius, S Carlson, M Chinowsky, W Chirkin, D Conrad, J Costa, CGS Cowen, D Dalberg, E DeYoung, T Edsjo, J Ekstrom, P Goobar, A Gray, L Hallgren, A Halzen, F Hardtke, R Hart, S He, Y de los Heros, CP Hill, G Hulth, PO Hundertmark, S Jacobsen, J Jones, A Kandhadai, V Karle, A Kim, J Leich, H Leuthold, M Lindahl, P Liubarsky, I Loaiza, P Lowder, D Marciniewski, P Miller, TC Miocinovic, P Mock, PC Morse, R Newcomer, M Niessen, P Nygren, D Porrata, R Potter, D Price, PB Przybylski, G Rhode, W Richter, S Rodriguez, J Romenesko, P Ross, D Rubinstein, H Schmidt, T Schneider, E Schwarz, R Schwendicke, U Smoot, G Solarz, M Sorin, V Spiering, C Steffen, P Stokstad, R Streicher, O Taboada, I Thon, T Tilav, S Walck, C Wiebusch, CH Wischnewski, R Woschnagg, K Wu, W Yodh, G Young, S CA AMANDA Collaboration TI The AMANDA neutrino telescope SO NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS LA English DT Article; Proceedings Paper CT 18th International Conference on Neutrino Physics and Astrophysics (Neutrino 98) CY JUN 04-09, 1998 CL TAKAYAMA, JAPAN SP Int Union Pure & Appl Phys & Sci Council Japan AB With an effective telescope area of order 10(4) m(2) for TeV neutrinos, a threshold near similar to 50 GeV and a pointing accuracy of 2.5 degrees per muon track, the AMANDA detector represents the first of a new generation of high energy neutrino telescopes, reaching a scale envisaged over 25 years ago. We describe early results on the calibration of natural deep ice as a particle detector as well as on AMANDA's performance as a neutrino telescope. C1 Univ Stockholm, S-10691 Stockholm, Sweden. Univ Calif Berkeley, Berkeley, CA 94720 USA. Univ Calif Irvine, Irvine, CA 92717 USA. Univ Penn, Philadelphia, PA 19104 USA. Univ Wisconsin, Madison, WI 53706 USA. Uppsala Univ, Uppsala, Sweden. Kalmar Univ, Kalmar, Sweden. DESY, Inst High Energy Phys, Hamburg, Germany. Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Andres, EC (reprint author), Univ Stockholm, S-10691 Stockholm, Sweden. RI Wiebusch, Christopher/G-6490-2012; Hundertmark, Stephan/A-6592-2010; Botner, Olga/A-9110-2013; Hallgren, Allan/A-8963-2013; Loaiza, Pia/D-5861-2013; OI Wiebusch, Christopher/0000-0002-6418-3008; Streicher, Ole/0000-0001-7751-1843 NR 9 TC 2 Z9 2 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-5632 J9 NUCL PHYS B-PROC SUP JI Nucl. Phys. B-Proc. Suppl. PD MAY PY 1999 VL 77 BP 474 EP 485 DI 10.1016/S0920-5632(99)00469-7 PG 12 WC Physics, Particles & Fields SC Physics GA 217KD UT WOS:000081497700064 ER PT J AU Heilbronn, L Cary, RS Cronqvist, M Deak, F Frankel, K Galonsky, A Holabird, K Horvath, A Kiss, A Kruse, J Ronningen, RM Schelin, H Seres, Z Stronach, CE Wang, J Zecher, P Zeitlin, C AF Heilbronn, L Cary, RS Cronqvist, M Deak, F Frankel, K Galonsky, A Holabird, K Horvath, A Kiss, A Kruse, J Ronningen, RM Schelin, H Seres, Z Stronach, CE Wang, J Zecher, P Zeitlin, C TI Neutron yields from 155 MeV nucleon carbon and helium stopping in aluminum SO NUCLEAR SCIENCE AND ENGINEERING LA English DT Article ID CROSS-SECTIONS; LENGTH TARGETS; 256-MEV PROTONS AB Neutron fluences have been measured from 155 MeV/nucleon (4)He and (12)C ions stopping in an Al target at laboratory angles between 10 and 160 deg. The resultant spectra were integrated over angle and energy above 10 MeV to produce total neutron yields. Comparison of the two systems shows that approximately two times as many neutrons are produced from 155 MeV/nucleon (4)He stopping in Al and 155 MeV/nucleon (12)C stopping in Al. Using an energy-dependent geometric cross-section formula to calculate the expected number of primary nuclear interactions shows that the (12)C + Al system has, within uncertainties, the same number of neutrons per interaction (0.99 +/- 0.03) as does the (4)He + Al system (1.02 +/- 0.03), despite the fact that (12)C has three times as many neutrons as does (4)He. Energy and angular distributions for both systems are also reported No major differences can be seen between the two systems in those distributions, except for the overall magnitude. Where possible, the (4)He + Al spectra are compared with previously measured spectra from 160 and 177.5 MeV/nucleon (4)He interactions in a variety of stopping targets. The reported spectra are consistent with previously measured spectra. The data were acquired to provide data applicable to problems dealing with the determination of the radiation risk to humans Engaged in long-term missions in space; however, the data are also of interest for issues related to the determination of the radiation environment in high-altitude flight, with shielding at high-energy heavy-ion accelerators and with doses delivered outside tumor sites treated,with high-energy hadronic beams. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Virginia Polytech Inst & State Univ, Dept Phys, Petersburg, VA 23806 USA. Eotvos Lorand Univ, Dept Atom Phys, H-1088 Budapest, Hungary. Michigan State Univ, Natl Superconducting Cyclotron Lab, E Lansing, MI 48824 USA. Michigan State Univ, Dept Phys, E Lansing, MI 48824 USA. San Francisco State Univ, Dept Phys, San Francisco, CA 94132 USA. CEFET PR, Dept Phys, BR-80230901 Curitiba, Parana, Brazil. KFKI, Res Inst Particle & Nucl Phys, H-1525 Budapest 114, Hungary. Virginia Polytech Inst & State Univ, Dept Phys, Petersburg, VA 23806 USA. RP Heilbronn, L (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, MS 29-100, Berkeley, CA 94720 USA. EM LHHeilbronn@LBL.gov RI Horvath, Akos/D-1056-2012; Heilbronn, Lawrence/J-6998-2013 OI Heilbronn, Lawrence/0000-0002-8226-1057 NR 22 TC 23 Z9 23 U1 0 U2 2 PU AMER NUCLEAR SOC PI LA GRANGE PK PA 555 N KENSINGTON AVE, LA GRANGE PK, IL 60526 USA SN 0029-5639 J9 NUCL SCI ENG JI Nucl. Sci. Eng. PD MAY PY 1999 VL 132 IS 1 BP 1 EP 15 PG 15 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 190AE UT WOS:000079938700001 PM 11989488 ER PT J AU Forsberg, CW AF Forsberg, CW TI Flow barrier system for long-term high-level-waste isolation: Experimental results - Comments SO NUCLEAR TECHNOLOGY LA English DT Letter C1 Oak Ridge Natl Lab, Engn Coordinat & Anal Sect, Div Chem Technol, Oak Ridge, TN 37831 USA. RP Forsberg, CW (reprint author), Oak Ridge Natl Lab, Engn Coordinat & Anal Sect, Div Chem Technol, POB 2008, Oak Ridge, TN 37831 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0029-5450 J9 NUCL TECHNOL JI Nucl. Technol. PD MAY PY 1999 VL 126 IS 2 BP 240 EP 241 PG 2 WC Nuclear Science & Technology SC Nuclear Science & Technology GA 186KP UT WOS:000079728700011 ER PT J AU Brualdi, RA Sanderson, JG AF Brualdi, RA Sanderson, JG TI Nested species subsets, gaps, and discrepancy SO OECOLOGIA LA English DT Article DE community structure; nestedness; null matrix; gaps; discrepancies ID PATTERNS; COOCCURRENCES; DISTRIBUTIONS; ARCHIPELAGOES; ASSEMBLAGES; SEQUENCES; MATRICES; ISLANDS; HABITAT AB The nested-subset hypothesis of Patterson and Atmar slates that species composition on islands with less species richness is a proper subset of those on islands with greater species richness. The sum of species absences, referred to as gaps, was suggested as a metric for nestedness, and null models have been used to test whether or not island species exhibited nestedness. Simberloff and Martin stated that finding examples of non-nested faunas was difficult. We revisit previous analyses of nested faunas and introduce a new metric we call "discrepancy" which we recommend as a measure for nestedness. We also recommend that the sample spaces conserve both row sums (number of species per site) and column sums (number of sites per species) derived from the incidence matrix. We compare our results to previous analyses. C1 Univ Florida, Dept Wildlife Ecol & Conservat, Gainesville, FL 32611 USA. Univ Wisconsin, Dept Math, Madison, WI 53706 USA. RP Sanderson, JG (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. EM jgs@c3serve.c3.lanl.gov NR 25 TC 110 Z9 112 U1 0 U2 9 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0029-8549 J9 OECOLOGIA JI Oecologia PD MAY PY 1999 VL 119 IS 2 BP 256 EP 264 DI 10.1007/s004420050784 PG 9 WC Ecology SC Environmental Sciences & Ecology GA 196RJ UT WOS:000080321100014 PM 28307976 ER PT J AU Boulet, P Dongarra, J Vivien, F AF Boulet, P Dongarra, J Vivien, F TI Static tiling for heterogeneous computing platforms SO PARALLEL COMPUTING LA English DT Article DE tiling; communication-computation overlap; mapping; limited resources; different-speed processors; heterogeneous networks ID WORKSTATIONS; PERFORMANCE; LOOPS AB In the framework of fully permutable loops, tiling has been extensively studied as a source-to-source program transformation. However, little work has been devoted to the mapping and scheduling of the tiles on physical processors. Moreover, targeting heterogeneous computing platforms has to the best of our knowledge, never been considered. In this paper we extend static tiling techniques to the context of limited computational resources with different-speed processors. In particular, we present efficient scheduling and mapping strategies that are asymptotically optimal. The practical usefulness of these strategies is fully demonstrated by MPI experiments on a heterogeneous network of workstations. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Ecole Normale Super Lyon, LIP, F-69364 Lyon 07, France. Univ Lille 1, LIFL, F-59655 Villeneuve Dascq, France. Univ Tennessee, Dept Comp Sci, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Math Sci Sect, Oak Ridge, TN 37831 USA. Univ Strasbourg, ICPS, F-67400 Illkirch, France. RP Boulet, P (reprint author), Ecole Normale Super Lyon, LIP, F-69364 Lyon 07, France. RI Dongarra, Jack/E-3987-2014; Boulet, Pierre/K-7600-2015 OI Boulet, Pierre/0000-0002-0373-4478 NR 23 TC 14 Z9 14 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-8191 J9 PARALLEL COMPUT JI Parallel Comput. PD MAY PY 1999 VL 25 IS 5 BP 547 EP 568 DI 10.1016/S0167-8191(99)00012-5 PG 22 WC Computer Science, Theory & Methods SC Computer Science GA 200UC UT WOS:000080557600004 ER PT J AU Robertson, JL Frase, HN Bogdanoff, PD Manley, ME Fultz, B McQueeney, RJ AF Robertson, JL Frase, HN Bogdanoff, PD Manley, ME Fultz, B McQueeney, RJ TI Phonon densities of states of gamma-cerium and delta-cerium measured by inelastic neutron scattering SO PHILOSOPHICAL MAGAZINE LETTERS LA English DT Article ID VIBRATIONAL ENTROPY; POWDER DIFFRACTION; DISORDERED NI3AL; APPROXIMATION; DISPERSION; ALLOYS; LA; CE AB Inelastic neutron scattering spectra were measured on Ce metal at temperatures near the fee (gamma) to bcc (delta) transition, and phonon DOS curves were obtained. A large difference in the phonon DOS of gamma-Ce and delta-Ce was found, and this difference accounts for a change in vibrational entropy of (0.51 +/- 0.05)k(B) atom(-1) at the gamma-delta transition. To be consistent with the latent heat of the gamma-delta transition, this large change in vibrational entropy should be accompanied by a thermodynamically-significant change in electronic entropy of the opposite sign. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. CALTECH, Div Engn & Appl Sci, Pasadena, CA 91125 USA. Univ Calif Los Alamos Natl Lab, Manuel Lujan Jr Neutron Scattering Ctr, Los Alamos, NM 87545 USA. RP Robertson, JL (reprint author), Oak Ridge Natl Lab, POB 2008, Oak Ridge, TN 37831 USA. RI Manley, Michael/N-4334-2015; McQueeney, Robert/A-2864-2016 OI McQueeney, Robert/0000-0003-0718-5602 NR 27 TC 11 Z9 12 U1 0 U2 0 PU TAYLOR & FRANCIS LTD PI LONDON PA ONE GUNPOWDER SQUARE, LONDON EC4A 3DE, ENGLAND SN 0950-0839 J9 PHIL MAG LETT JI Philos. Mag. Lett. PD MAY PY 1999 VL 79 IS 5 BP 297 EP 304 DI 10.1080/095008399177372 PG 8 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Physics, Applied; Physics, Condensed Matter SC Materials Science; Metallurgy & Metallurgical Engineering; Physics GA 193WB UT WOS:000080159800012 ER PT J AU Ji, HF Dabestani, R Brown, GM Hettich, RL AF Ji, HF Dabestani, R Brown, GM Hettich, RL TI Spacer length effect on the photoinduced electron transfer fluorescent probe for alkali metal ions SO PHOTOCHEMISTRY AND PHOTOBIOLOGY LA English DT Article ID SENSORS AB We have synthesized four derivatives of alkyl pyrene covalently bonded to aza-18-crown-6 at the nitrogen position, Py(CH2)(n), (n = 1-4), to study the effect of spacer length on the emission properties of pyrene fluorophore upon complexation of alkali metal ions by the crown moiety, Zn the absence of alkali metal ions, the parent molecule is weakly fluorescent because its emission is partially quenched by photoinduced electron transfer (PET) from nitrogen lone pairs to the excited singlet state of pyrene, Complexation of alkali metal ions (e.g. K+) by the crown moiety prevents the nitrogen lone pair from participating in PET and results in an enhancement in the observed emission from pyrene (fluorescent turn on). Because the PET effect could be exerted through bonds as well as space, its magnitude may show a dependence on chain length, We have examined the fluorescence behavior of these pyrene aza-crown ether derivatives in the presence of alkali metal ions to determine the magnitude of such an effect and its impact on the sensitivity of the fluorescent probe for detection purposes. Our results indicate that maximum efficiency for PET between the pyrene moiety and aza-crown ether is achieved when n less than or equal to 3. C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Dabestani, R (reprint author), Oak Ridge Natl Lab, Div Chem & Analyt Sci, POB 2008,MS-6100, Oak Ridge, TN 37831 USA. EM dabestanir@ornl.gov RI Hettich, Robert/N-1458-2016 OI Hettich, Robert/0000-0001-7708-786X NR 16 TC 41 Z9 41 U1 1 U2 10 PU AMER SOC PHOTOBIOLOGY PI AUGUSTA PA BIOTECH PARK, 1021 15TH ST, SUITE 9, AUGUSTA, GA 30901-3158 USA SN 0031-8655 J9 PHOTOCHEM PHOTOBIOL JI Photochem. Photobiol. PD MAY PY 1999 VL 69 IS 5 BP 513 EP 516 DI 10.1562/0031-8655(1999)069<0513:SLEOTP>2.3.CO;2 PG 4 WC Biochemistry & Molecular Biology; Biophysics SC Biochemistry & Molecular Biology; Biophysics GA 197HK UT WOS:000080359200001 ER PT J AU Knox, RS Brown, JS Laible, PD Talbot, MFJ AF Knox, RS Brown, JS Laible, PD Talbot, MFJ TI Part of the fluorescence of chlorophyll a may originate in excited triplet states SO PHOTOSYNTHESIS RESEARCH LA English DT Article DE absorption; Kennard-Stepanov theory; photosynthesis; spectral equilibration; thermal equilibration ID BACTERIOCHLOROPHYLL-A; COLUMN CHROMATOGRAPHY; SEPHAROSE CL-6B; ENERGY-TRANSFER; ABSORPTION; PERIDININ; PROTEIN; SPECTRA; COMPLEX; SOLVENTS AB Absorption and fluorescence spectra of chlorophyll a have been analyzed on the basis of an extended version of Kennard-Stepanov (KS) theory. It is proposed that at least one new electronic state lies just below the normal S-1 - S-0 transition (Q(y)), borrowing approximately 2-4% of its strength and contributing to the fluorescence in the tail. The KS anomalies leading to this hypothesis occur in a wide variety of cases, including chlorophyll a in solution and protein-bound chlorophyll a, suggesting that the phenomenon is an intrinsic property of the molecule. Natural candidates for the new state(s) are the second and third triplet states. The relationship of the fluorescence excitation spectrum to KS theory is investigated and applied to explain a red drop in yield. C1 Univ Rochester, Dept Phys & Astron, Rochester, NY 14627 USA. Univ Rochester, Rochester theory Ctr Opt Sci & Engn, Rochester, NY 14627 USA. Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. Argonne Natl Lab, Ctr Mechanist Biol & Biotechnol, Argonne, IL 60439 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Struct Biol Div, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. RP Knox, RS (reprint author), Univ Rochester, Dept Phys & Astron, Rochester, NY 14627 USA. EM rsk@pas.rochester.edu NR 34 TC 9 Z9 9 U1 0 U2 1 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0166-8595 EI 1573-5079 J9 PHOTOSYNTH RES JI Photosynth. Res. PD MAY PY 1999 VL 60 IS 2-3 BP 165 EP 177 DI 10.1023/A:1006284510090 PG 13 WC Plant Sciences SC Plant Sciences GA 225GJ UT WOS:000081949800004 ER PT J AU Hoover, WG Hess, S AF Hoover, WG Hess, S TI Anisotropic plasticity with embedded-atom potentials SO PHYSICA A LA English DT Article DE plasticity; anisotropicity; nonequilibrium molecular dynamics ID NONEQUILIBRIUM MOLECULAR-DYNAMICS; SIMULATIONS; EQUILIBRIUM AB Embedded-atom potentials are a useful supplement to pair potentials in the modelling of defects and metal plasticity, Here we emphasize the steady isothermal shear deformation of two-dimensional models made up of many interacting grains. The embedded-atom-plus-pairs potential can provide very anisotropic grains, which are oriented by the shear deformation, We simulate plastic shear deformation, at fixed density and temperature, with the Sllod and Doll's-Tensor algorithms. We explore the temperature-dependent elastic and plastic moduli for two relatively anisotropic models with static anisotropicities similar to those of the coinage and alkali metals. In both cases the flow stress is relatively insensitive to strain rate at moderate strain rates, At high strain rates shear bands develop. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Univ Calif Lawrence Livermore Natl Lab, Dept Appl Sci, Livermore, CA 94551 USA. Tech Univ Berlin, Inst Theoret Phys, D-10623 Berlin, Germany. RP Hoover, WG (reprint author), Univ Calif Lawrence Livermore Natl Lab, Dept Appl Sci, Livermore, CA 94551 USA. NR 18 TC 11 Z9 11 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0378-4371 J9 PHYSICA A JI Physica A PD MAY 1 PY 1999 VL 267 IS 1-2 BP 98 EP 110 DI 10.1016/S0378-4371(98)00671-2 PG 13 WC Physics, Multidisciplinary SC Physics GA 194AU UT WOS:000080170600005 ER PT J AU Petrenko, OA Paul, DM Ritter, C Zeiske, T Yethiraj, M AF Petrenko, OA Paul, DM Ritter, C Zeiske, T Yethiraj, M TI Magnetic frustration and order in gadolinium gallium garnet SO PHYSICA B-CONDENSED MATTER LA English DT Article; Proceedings Paper CT 4th International Workshop on Quasi-Elastic Neutron Scattering (QENS 98) CY AUG 06-08, 1998 CL NYKOPING, SWEDEN SP Swedish Res Council Nat Sci DE spin liquid; magnetic frustration; Monte Carlo simulation; antiferromagnet ID HEAT; ANTIFERROMAGNET; TRANSITION AB In gadolinium gallium garnet (GGG) there is no long-range magnetic order down to 25 mK even though the Curie-Weiss temperature is - 2 K. Instead, over a wide temperature range GGG supports short-range magnetic order (spin liquid), while long-range order can be induced by an applied magnetic field. It is believed that the geometrical frustration of the magnetic interactions is responsible for this behaviour: in GGG the magnetic Gd ions are located on a triangular lattice. We have investigated the magnetic properties of GGG by neutron diffraction measurements. The results show clearly the development of short-range magnetic order without an applied field and the appearance of long range order in an applied magnetic field. A comparison of the experimental data with classical Monte Carlo simulations results provides us with hrm conclusions about the relative strength of the magnetic interactions in GGG and their importance in the formation of a magnetic ground state. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Univ Warwick, Dept Phys, Coventry CV4 7AL, W Midlands, England. Inst Laue Langevin, F-38042 Grenoble, France. Hahn Meitner Inst Berlin GmbH, D-14109 Berlin, Germany. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Petrenko, OA (reprint author), Univ Warwick, Dept Phys, Coventry CV4 7AL, W Midlands, England. EM oleg@longjohn.phys.warwick.ac.uk RI Petrenko, Oleg/E-2717-2013 OI Petrenko, Oleg/0000-0003-1529-303X NR 18 TC 22 Z9 22 U1 1 U2 10 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 EI 1873-2135 J9 PHYSICA B JI Physica B PD MAY PY 1999 VL 266 IS 1-2 BP 41 EP 48 DI 10.1016/S0921-4526(98)01490-2 PG 8 WC Physics, Condensed Matter SC Physics GA 185VT UT WOS:000079692200007 ER PT J AU Schleger, P Ehlers, G Kollmar, A Alefeld, B Barthelemy, JF Casalta, H Farago, B Giraud, P Hayes, C Lartigue, C Mezei, F Richter, D AF Schleger, P Ehlers, G Kollmar, A Alefeld, B Barthelemy, JF Casalta, H Farago, B Giraud, P Hayes, C Lartigue, C Mezei, F Richter, D TI The sub-neV resolution NSE spectrometer IN15 at the Institute Laue-Langevin SO PHYSICA B-CONDENSED MATTER LA English DT Article; Proceedings Paper CT 4th International Workshop on Quasi-Elastic Neutron Scattering (QENS 98) CY AUG 06-08, 1998 CL NYKOPING, SWEDEN SP Swedish Res Council Nat Sci DE neutron spin echo; instrumentation; reptation; nano-particles; neV resolution ID NEUTRON; PARTICLES; DESIGN AB A new ultra-high-resolution neutron spin-echo spectrometer at the ILL, Grenoble, extends the time range for measurements of the intermediate scattering function S(q, t) far beyond what has previously been possible. This new dynamic range approaching the microsecond opens up the possibility for exploring dynamic phenomena which have been previously unobservable. The various design ideas for the three operational modes (standard, neutron optical focusing, and time of flight) will be presented. The standard and focusing configurations are currently operational. In the normal mode, Fourier times between 0.03 and 360 ns and momentum transfers q between 0.01 and 0.6 Angstrom(-1) are accessible. Under focusing conditions, the smallest attainable q is about 0.002 Angstrom(-1), and closes the gap to light scattering. Two examples of experiments will be presented: the reptation dynamics in an entangled linear polymer melt, and the superparamagnetic fluctuations of magnetic monodomain nano-particles. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Inst Max Von Laue Paul Langevin, F-38042 Grenoble 9, France. Forschungszentrum Julich, Inst Festkorperforsch, D-52428 Julich, Germany. Hahn Meitner Inst Berlin GmbH, D-14109 Berlin, Germany. Spectrometrie Phys Lab, F-38402 St Martin Dheres, France. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Inst Max Von Laue Paul Langevin, BP 156X, F-38042 Grenoble 9, France. EM schleger@ill.fr RI Farago, Bela/H-4544-2012; Richter, Dieter/H-3701-2013; Ehlers, Georg/B-5412-2008 OI Richter, Dieter/0000-0003-0719-8470; Ehlers, Georg/0000-0003-3513-508X NR 15 TC 25 Z9 25 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4526 EI 1873-2135 J9 PHYSICA B JI Physica B PD MAY PY 1999 VL 266 IS 1-2 BP 49 EP 55 DI 10.1016/S0921-4526(98)01491-4 PG 7 WC Physics, Condensed Matter SC Physics GA 185VT UT WOS:000079692200008 ER PT J AU Aeppli, G Bishop, DJ Broholm, C Bucher, E Cheong, SW Dai, P Fisk, Z Hayden, SM Kleiman, R Mason, TE Mook, HA Perring, TG Schroeder, A AF Aeppli, G Bishop, DJ Broholm, C Bucher, E Cheong, SW Dai, P Fisk, Z Hayden, SM Kleiman, R Mason, TE Mook, HA Perring, TG Schroeder, A TI Neutron scattering and the search for mechanisms of superconductivity SO PHYSICA C LA English DT Article; Proceedings Paper CT 1st Euroconference on Anomalous Complex Superconductors CY SEP 26-OCT 03, 1998 CL AGHIA PELAGIA, GREECE SP Commiss European Union DE neutron scattering; superconductivity; exotic ID MAGNETIC FLUCTUATIONS; VORTEX LATTICE; UPT3; LA2-XSRXCUO4; TEMPERATURE; STATES; ORDER; ANTIFERROMAGNETISM; LA1.86SR0.14CUO4; LA1.85SR0.15CUO4 AB Neutron scattering is a direct probe of mass and magnetization density in solids. We start with a brief review of experimental strategies for determining the mechanisms of superconductivity and how neutron scattering contributed towards our understanding of conventional superconductors. The remainder of the article gives examples of neutron results with impact on the search for the mechanism of superconductivity in more recently discovered, 'exotic', materials, namely the heavy fermion compounds and the layered cuprates, (C) 1999 Elsevier Science B.V. All rights reserved. C1 Riso Natl Lab, DK-4000 Roskilde, Denmark. AT&T Bell Labs, Murray Hill, NJ 07974 USA. Johns Hopkins Univ, Baltimore, MD 21218 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Natl High Magnet Field Lab, Tallahassee, FL USA. Univ Bristol, Bristol BS8 1TL, Avon, England. Rutherford Appleton Lab, Didcot OX11 0QX, Oxon, England. Univ Karlsruhe, D-76128 Karlsruhe, Germany. RP Aeppli, G (reprint author), NEC, Princeton, NJ 08540 USA. RI Broholm, Collin/E-8228-2011; Hayden, Stephen/F-4162-2011; Dai, Pengcheng /C-9171-2012; Mason, Thomas/M-5809-2014 OI Broholm, Collin/0000-0002-1569-9892; Hayden, Stephen/0000-0002-3209-027X; Dai, Pengcheng /0000-0002-6088-3170; Mason, Thomas/0000-0003-1880-3971 NR 35 TC 2 Z9 2 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 MAY PY 1999 VL 317 BP 9 EP 17 DI 10.1016/S0921-4534(99)00041-6 PG 9 WC Physics, Applied SC Physics GA 211QV UT WOS:000081173100003 ER PT J AU Stassis, C Zarestky, J Goldman, AI Canfield, PC Shirane, G Shapiro, S AF Stassis, C Zarestky, J Goldman, AI Canfield, PC Shirane, G Shapiro, S TI Anomalous phonons below T-c in superconducting RNi2B2C (R = Lu, Y) SO PHYSICA C LA English DT Article; Proceedings Paper CT 1st Euroconference on Anomalous Complex Superconductors CY SEP 26-OCT 03, 1998 CL AGHIA PELAGIA, GREECE SP Commiss European Union DE phonon; superconductor; anomalous temperature dependence ID SCATTERING; NEUTRON AB The phonons that exhibit anomalous temperature dependence in these compounds have wave vectors close to <(xi)over right arrow>(m) = (xi,0,0), with xi congruent to 0.5, and belong to two Delta(4)[xi 00] branches (one acoustic and the other optic) which cannot cross by symmetry. The behavior of these phonon modes was studied systematically between 2 and 620 K. We find that above T-c the frequencies of the acoustic modes decrease with decreasing temperature, and there is intensity transfer from the upper (optic) to the lower (acoustic) mode in both compounds. As the temperature decreases towards T-c, the two branches approach each other in the vicinity of <(xi)over right arrow>(m) for the Lu compound, whereas they separate in the Y compound. This behavior, above T-c, can be satisfactorily explained by a couple-mode model. Below T-c the phonon spectrum changes dramatically: in both compounds, it consists of a sharp peak at approximately 4 meV with a broad weak shoulder on the high-energy side. The width of the sharp peak remains practically constant but its intensity decreases with increasing temperature and vanishes in the vicinity of T-c. The results below T-c are in qualitative agreement with recent theoretical calculations. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Dept Phys & Astron, Ames, IA 50011 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. RP Stassis, C (reprint author), Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. EM stassis@ameslab.gov RI Canfield, Paul/H-2698-2014 NR 12 TC 5 Z9 5 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 MAY PY 1999 VL 317 BP 127 EP 133 DI 10.1016/S0921-4534(99)00052-0 PG 7 WC Physics, Applied SC Physics GA 211QV UT WOS:000081173100013 ER PT J AU Abrikosov, AA AF Abrikosov, AA TI Resonant tunneling in high-T-c superconductors (review) SO PHYSICA C LA English DT Article; Proceedings Paper CT 1st Euroconference on Anomalous Complex Superconductors CY SEP 26-OCT 03, 1998 CL AGHIA PELAGIA, GREECE SP Commiss European Union DE resonant tunneling; high-T-c; superconductors; cuprates ID HIGH-TEMPERATURE SUPERCONDUCTORS; DIMENSIONAL COULOMB GAS; VALENCE-BOND STATE; OPTICAL CONDUCTIVITY; AXIS CONDUCTIVITY; NORMAL TRANSPORT; SINGLE-CRYSTALS; PSEUDOGAP; BI2SR2CACU2O8; DIAGNOSTICS AB Papers are reviewed on the resonant tunneling mechanism of the c-axis transport in high-temperature superconducting layered cuprates, proposed by the present author. After an introduction, where the problem is stated and the qualitative principles of the mechanism are described, real physical properties are calculated and compared with experimental data. These include the temperature dependence of the static c-axis conductivity in the normal state, frequency dependence of the optical conductivity and stationary supercurrent along the c-axis. It is demonstrated that for the latter the coherence of resonant tunneling through different centers is of primary importance. In the last section an explanation is proposed of the drastic decrease of T-c ad increase of the BCS ratio 2 Delta(0)/T-c with underdoping, based on the disruption of interlayer connection and appearance of vortex fluctuations. Two appendices are added illustrating some important features of resonant tunneling on simple models. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Abrikosov, AA (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. EM abrikosov@anl.gov NR 47 TC 32 Z9 32 U1 2 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 MAY PY 1999 VL 317 BP 154 EP 174 DI 10.1016/S0921-4534(99)00056-8 PG 21 WC Physics, Applied SC Physics GA 211QV UT WOS:000081173100017 ER PT J AU Boothroyd, AT Hill, JP McMorrow, DF Andersen, NH Stunault, A Vettier, C Wolf, T AF Boothroyd, AT Hill, JP McMorrow, DF Andersen, NH Stunault, A Vettier, C Wolf, T TI Incommensurate magnetism in non-superconducting PrBa2Cu3O6.92 SO PHYSICA C LA English DT Article; Proceedings Paper CT 1st Euroconference on Anomalous Complex Superconductors CY SEP 26-OCT 03, 1998 CL AGHIA PELAGIA, GREECE SP Commiss European Union DE PrBa2Cu3O6+x; magnetic order; resonant X-ray magnetic scattering; neutron scattering ID PR; ORDER; Y1-XPRXBA2CU3O7 AB We report the discovery of incommensurate magnetic order in non-superconducting single crystals PrBa2Cu3O6.92. Resonant X-ray magnetic scattering at the Pr L-II and L-III edges and high resolution neutron diffraction were used to characterise the magnetic order on the different magnetic sublattices. The data reveal that the Pr sublattice orders at a temperature of 19 K in an incommensurate structure with ordering wavevector (0.5 +/- delta, 0.5, 0) or (0.5, 0.5 +/- delta, 0), delta approximate to 0.006-0.008, A spin reorientation in the Pr sublattice to a commensurate antiferromagnetic structure with ordering wavevector (0.5, 0.5, 0.5) takes place at a temperature close to 9 K. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Univ Oxford, Dept Phys, Oxford OX1 3PU, England. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Riso Natl Lab, Condensed Matter Phys & Chem Dept, DK-4000 Roskilde, Denmark. European Synchrotron Radiat Facil, F-38043 Grenoble, France. Forschungszentrum Karlsruhe, ITP, D-76021 Karlsruhe, Germany. RP Boothroyd, AT (reprint author), Univ Oxford, Dept Phys, Oxford OX1 3PU, England. EM a.boothroyd1@physics.ox.ac.uk RI McMorrow, Desmond/C-2655-2008; Andersen, Niels/A-3872-2012 OI McMorrow, Desmond/0000-0002-4947-7788; NR 19 TC 6 Z9 6 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 MAY PY 1999 VL 317 BP 292 EP 298 DI 10.1016/S0921-4534(99)00071-4 PG 7 WC Physics, Applied SC Physics GA 211QV UT WOS:000081173100032 ER PT J AU Ronning, F Kim, C Shen, ZX AF Ronning, F Kim, C Shen, ZX TI Fermi surface evolution in cuprates: an angle-resolved photoemission study SO PHYSICA C LA English DT Article; Proceedings Paper CT 1st Euroconference on Anomalous Complex Superconductors CY SEP 26-OCT 03, 1998 CL AGHIA PELAGIA, GREECE SP Commiss European Union DE Fermi; cuprate; photoemission ID MODEL AB We report angle-resolved photoemission measurements on an insulating CuO2 plane compound, Ca2CuO2Cl2. This so-called parent compound to the high-ir, superconductors is a Mott insulator. We observe that the lowest energy feature loses its spectral weight as it crosses the approximate position where band theory predicts the existence of the Fermi surface. Complemented with an analysis from metallic Bi2Sr2CaCu2O8 (Bi2212), this suggests that the loss of spectral weight is due to the remnants of the non-interacting Fermi surface. Further analysis shows a d-wave-like dispersion along this 'Fermi surface' contour that is destroyed in the insulator. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Stanford Univ, Dept Phys, Stanford, CA 94305 USA. Stanford Univ, Dept Appl Phys, Stanford, CA 94305 USA. Stanford Univ, Stanford Synchrotron Radiat Lab, Stanford, CA 94305 USA. RP Shen, ZX (reprint author), Stanford Univ, Dept Phys, Stanford, CA 94305 USA. EM shen@ee.stanford.edu NR 11 TC 0 Z9 0 U1 2 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 MAY PY 1999 VL 317 BP 320 EP 324 DI 10.1016/S0921-4534(99)00075-1 PG 5 WC Physics, Applied SC Physics GA 211QV UT WOS:000081173100036 ER PT J AU Tissen, VG Wang, Y Paulikas, AP Veal, BW Schilling, JS AF Tissen, VG Wang, Y Paulikas, AP Veal, BW Schilling, JS TI Pressure dependence of T-c in strongly underdoped YBa2Cu3O6.41 as a function of pressure-temperature history SO PHYSICA C LA English DT Article DE pressure; temperature; high-T-c superconductor ID OXYGEN; SUPERCONDUCTORS; DIFFUSION AB The dependence of the superconducting transition temperature T-c(P) of strongly underdoped YBa2Cu3O6.41 [T-c(1 bar) similar or equal to 14 K] on hydrostatic pressure is determined to 7 GPa in an ac susceptibility measurement in a diamond-anvil-cell loaded with dense helium as pressure medium. T-c(P) is found to depend markedly on the temperature-pressure history due to the importance of relaxation processes in the oxygen sublattice. The relaxation time tau increases exponentially with pressure, corresponding to an activation volume of +4.2 cm(3)/mol. The 'intrinsic' T-c(P)-dependence (that devoid of relaxation effects) is determined whereby T-c initially increases with pressure, passes through a maximum near 17 K at 2 GPa, and falls below 1.6 K above 7 GPa. (C) 1999 Published by Elsevier Science B.V. All rights reserved. C1 Washington Univ, Dept Phys, St Louis, MO 63130 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Inst Solid State Phys, Chernogolovka 142432, Russia. RP Schilling, JS (reprint author), Washington Univ, Dept Phys, CB 1105,1 Brookings Dr, St Louis, MO 63130 USA. NR 13 TC 15 Z9 15 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 MAY 1 PY 1999 VL 316 IS 1-2 BP 21 EP 26 DI 10.1016/S0921-4534(99)00261-0 PG 6 WC Physics, Applied SC Physics GA 202BZ UT WOS:000080633400003 ER PT J AU Cui, X List, FA Kroeger, DM Goyal, A Lee, DF Mathis, JE Specht, ED Martin, PM Feenstra, R Verebelyi, DT Christen, DK Paranthaman, M AF Cui, X List, FA Kroeger, DM Goyal, A Lee, DF Mathis, JE Specht, ED Martin, PM Feenstra, R Verebelyi, DT Christen, DK Paranthaman, M TI Continuous growth of epitaxial CeO2 buffer layers on rolled Ni tapes by electron beam evaporation SO PHYSICA C LA English DT Article DE applications of high-T-c superconductors; continuous deposition; biaxial texture; rolled Ni substrates; E-beam evaporation ID HIGH-TEMPERATURE SUPERCONDUCTORS; CRITICAL-CURRENT DENSITY; TEXTURED NI; FILMS; DEPOSITION; OXIDATION; NI(100); OXYGEN; METAL AB A reel-to-reel, electron beam evaporation system has been developed to continuously deposit epitaxial CeO2 and other oxide buffer layers on meter long-lengths of rolled Ni tapes. The deposition system includes two interconnected electron beam evaporation chambers and a chamber in which as-rolled Ni tape is in situ annealed to develop biaxial texture. An integral reel-to-reel system with tension control enables motion of the tape with little or no plastic deformation. When depositing epitaxial oxides on Ni, the formation of unfavorably oriented NiO needs to be avoided. Oxide-free, {100}[100]-oriented Ni tapes are prepared by control of the partial pressure of H-2 during Ni annealing. In situ annealed rolled Ni tape over 70 cm long and 1 cm wide has been deposited with an epitaxial CeO2 buffer layer. Critical current density as high as 700 000 A/cm(2) at 77 K in self-field has been achieved for TiBa2Cu3O7-x (YBCO) films deposited on short segments of these buffered substrates. X-ray in-plane phi-scans have been performed as a function of length to determine the crystallographic consistency of the epitaxial CeO2 over length. Results of scanning electron microscopy (SEM) examinations of the CeO2 buffer layer microstructure are presented. (C) 1999 Published by Elsevier Science B.V. All rights reserved. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Cui, X (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, Bldg 4500S,M-S 6116,POB 2008, Oak Ridge, TN 37831 USA. RI Specht, Eliot/A-5654-2009; Paranthaman, Mariappan/N-3866-2015 OI Specht, Eliot/0000-0002-3191-2163; Paranthaman, Mariappan/0000-0003-3009-8531 NR 18 TC 29 Z9 30 U1 0 U2 8 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD MAY 1 PY 1999 VL 316 IS 1-2 BP 27 EP 33 DI 10.1016/S0921-4534(99)00248-8 PG 7 WC Physics, Applied SC Physics GA 202BZ UT WOS:000080633400004 ER PT J AU Carroll, TX Berrah, N Bozek, J Hahne, J Kukk, E Saethre, LJ Thomas, TD AF Carroll, TX Berrah, N Bozek, J Hahne, J Kukk, E Saethre, LJ Thomas, TD TI Carbon 1s photoelectron spectrum of methane: Vibrational excitation and core-hole lifetime SO PHYSICAL REVIEW A LA English DT Article ID POST-COLLISION INTERACTION; INNER-SHELL PHOTOIONIZATION; QUARTIC FORCE-FIELD; HIGH-RESOLUTION; ELECTRON-IMPACT; AUGER PROCESSES; NEAR-THRESHOLD; QUANTUM-THEORY; IONIZATION; STATES AB The carbon Is photoelectron spectrum has been measured for CH4 at photon energies of 302, 320, and 330 eV and for CD4 at 330 eV with an instrumental resolution about half the natural linewidth. These spectra have been analyzed to obtain vibrational spacings, vibrational intensities, and the lifetime of the carbon Is core-hole state. The vibrational intensities vary with photon energy, in agreement with earlier results. At 330 eV, the observed Franck-Condon factors for both CH4 and CD4 can be understood only if anharmonic effects (consistent with the predictions of theory) are included. On the other hand, the vibrational spacings in CH4 show no evidence for anharmonicity (in contrast with theoretical predictions). In CD, the observed anharmonicity in the vibrational energy spacings is about half of the predicted value, but the experimental and theoretical values differ only by an amount comparable to the experimental uncertainty. The measured values of the lifetime show a dependence on photon energy; this is attributed to failure of the theory of post-collision interaction to predict correctly the observed electron spectrum near threshold. At 330 eV, the measured Lorentzian lifetime, 93-95 meV, agrees with predictions of simple theory, but not with the prediction of more complete theory. It is also observed that there are systematic discrepancies between the observed line shapes and those predicted by the theory of postcollision interaction. [S1050-2947(99)02305-7]. C1 Keuka Coll, Keuka Pk, NY 14478 USA. Western Michigan Univ, Dept Phys, Kalamazoo, MI 49008 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Adv Light Source, Berkeley, CA 94720 USA. Oregon State Univ, Dept Chem, Corvallis, OR 97331 USA. Univ Bergen, Dept Chem, N-5007 Bergen, Norway. RP Carroll, TX (reprint author), Keuka Coll, Keuka Pk, NY 14478 USA. RI Bozek, John/E-4689-2010; Bozek, John/E-9260-2010 OI Bozek, John/0000-0001-7486-7238 NR 32 TC 68 Z9 68 U1 0 U2 9 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 MAY PY 1999 VL 59 IS 5 BP 3386 EP 3393 DI 10.1103/PhysRevA.59.3386 PG 8 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 197UB UT WOS:000080383100035 ER PT J AU Puttner, R Dominguez, I Morgan, TJ Cisneros, C Fink, RF Rotenberg, E Warwick, T Domke, M Kaindl, G Schlachter, AS AF Puttner, R Dominguez, I Morgan, TJ Cisneros, C Fink, RF Rotenberg, E Warwick, T Domke, M Kaindl, G Schlachter, AS TI Vibrationally resolved O 1s core-excitation spectra of CO and NO SO PHYSICAL REVIEW A LA English DT Article ID HIGH-RESOLUTION; CARBON-MONOXIDE; RYDBERG SERIES; PHOTOIONIZATION; PHOTOABSORPTION; PHOTOELECTRON; SPECTROSCOPY; MOLECULES; N2; STATES AB High-resolution photoabsorption spectra of CO and NO below the O is ionization threshold are presented. The vibrational fine structure of the O 1s-->pi* and O 1s(-1) Rydberg excitations could be resolved for both molecules, allowing a determination of the vibrational energies and intramolecular distances of the core-excitation states in CO and NO from Franck-Condon analyses. Ab initio calculations are performed for the O 1s--> pi* excitation in CO to give an independent confirmation of the spectroscopic parameters derived from the Franck-Condon analysis. The spectral features of the O 1s(-1) Rydberg region in CO are reassigned on the basis of the experimental results. The results obtained for the O 1s(-1)3s Rydberg state in NO support the idea of a weakening of the molecular bond upon an O 1s(-1) ionization process. [S1050-2947 (99)06205-8]. C1 Free Univ Berlin, Inst Phys Expt, D-14195 Berlin, Germany. Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Wesleyan Univ, Dept Phys, Middletown, CT 06459 USA. Inst Fis, Cuernavaca 62191, Morelos, Mexico. Ruhr Univ Bochum, Lehrstuhl Theoret Chem, D-44780 Bochum, Germany. RP Puttner, R (reprint author), Univ Oulu, Dept Phys Sci, FIN-90570 Oulu, Finland. RI Rotenberg, Eli/B-3700-2009; Fink, Reinhold/A-3239-2016; Dominguez-Lopez, Ivan/B-6072-2016 OI Rotenberg, Eli/0000-0002-3979-8844; Fink, Reinhold/0000-0002-8288-924X; Dominguez-Lopez, Ivan/0000-0001-8084-8711 NR 39 TC 57 Z9 57 U1 0 U2 10 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 MAY PY 1999 VL 59 IS 5 BP 3415 EP 3423 DI 10.1103/PhysRevA.59.3415 PG 9 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 197UB UT WOS:000080383100040 ER PT J AU Rochester, S Bowers, CJ Budker, D DeMille, D Zolotorev, M AF Rochester, S Bowers, CJ Budker, D DeMille, D Zolotorev, M TI Measurement of lifetimes and tensor polarizabilities of odd-parity states of atomic samarium SO PHYSICAL REVIEW A LA English DT Article ID HIGH-ACCURACY CALCULATION; ELECTRIC-DIPOLE MOMENT; LOW-LYING LEVELS; SM-I; TRANSITION-PROBABILITIES; METASTABLE-STATE; ISOTOPE SHIFTS; RARE-EARTH; YTTERBIUM; CESIUM AB A systematic measurement of the lifetimes and tensor polarizabilities of the lowest-lying odd-parity levels of Sm I was performed. The lifetimes were measured by detecting time-resolved fluorescence following pulsed-laser excitation of atoms in an atomic beam; polarizabilities were measured employing the method of Stask-induced quantum beats. An analysis of the data is undertaken to find the best even-parity candidate states for an atomic electric dipole moment (EDM) measurement. For the most favorable candidate state ((7)G(1)), the electron EDM enhancement factor is evaluated to be in the range \R\approximate to 100-3800. Critical analysis of the present data along with earlier results in Sm shows the necessity of a term reassignment for several odd-parity states. This term reassignment is also used in an estimate of the parity-nonconserving F-7(0)-(7)G(1) amplitude. [S1050-2947(99)10405-0]. C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. Yale Univ, Dept Phys, New Haven, CT 06520 USA. Lawrence Berkeley Lab, Ctr Beam Phys, Berkeley, CA 94720 USA. RP Rochester, S (reprint author), Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. RI Budker, Dmitry/F-7580-2016 OI Budker, Dmitry/0000-0002-7356-4814 NR 63 TC 22 Z9 22 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD MAY PY 1999 VL 59 IS 5 BP 3480 EP 3494 DI 10.1103/PhysRevA.59.3480 PG 15 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 197UB UT WOS:000080383100047 ER PT J AU Bowers, CJ Budker, D Freedman, SJ Gwinner, G Stalnaker, JE DeMille, D AF Bowers, CJ Budker, D Freedman, SJ Gwinner, G Stalnaker, JE DeMille, D TI Experimental investigation of the 6s(2) S-1(0)-> 5d6s D-3(1,2) forbidden transitions in atomic ytterbium SO PHYSICAL REVIEW A LA English DT Article ID PARITY NONCONSERVATION; VIOLATION; CESIUM; THALLIUM; YB AB We have observed the Stark-induced 6s(2) S-1(0)-->5d6s D-3(1) transition in Yb, and measured properties relevant to the study of atomic parity nonconservation in this transition. An atomic beam of Yb is excited by 408-nm light in the presence of an external de electric field, resulting in cascade fluorescence at 556 nm as the excitation decays through the 6s6p P-3, state. The density of the atomic beam and the fluorescence detection efficiency are calibrated by directly exciting the 6s6p P-3(1) State with 556-nm light. Using an estimate of the D-3(1)-P-3(1) branching fraction, we obtain a measurement of the vector transition polarizability, \beta\ = 2.18(33) x 10(-8) ea(0)/(V/cm). In addition, we have observed the 6s(2 1)S(0)-->5d6s D-3(2) transition at 404 nm. The electric quadrupole transition amplitude and tensor transition polarizability have been measured. We have also measured the de Stark shifts, hyperfine structure, and isotope shifts for both transitions. [S1050-2947(99)11905-X]. C1 Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Yale Univ, Dept Phys, New Haven, CT 06520 USA. RP Bowers, CJ (reprint author), SBC Technol Resources Inc, 9505 Arboretum Blvd, Austin, TX 78759 USA. RI Budker, Dmitry/F-7580-2016 OI Budker, Dmitry/0000-0002-7356-4814 NR 38 TC 30 Z9 30 U1 1 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 MAY PY 1999 VL 59 IS 5 BP 3513 EP 3526 DI 10.1103/PhysRevA.59.3513 PG 14 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 197UB UT WOS:000080383100050 ER PT J AU Ionescu, DC Sorensen, AH Belkacem, A AF Ionescu, DC Sorensen, AH Belkacem, A TI Inner-shell photoionization at relativistic energies SO PHYSICAL REVIEW A LA English DT Article ID HEAVY-ION COLLISIONS; POSITRON PAIR PRODUCTION; DOUBLE-IONIZATION; CROSS-SECTIONS; SINGLE IONIZATION; BOUND-ELECTRON; PHOTON IMPACT; HELIUM; CREATION; CAPTURE AB At relativistic energies the cross section for the atomic photoelectric effect drops off as does the cross section for liberating any bound electron through Compton scattering. However, when the photon energy exceeds twice the rest mass of the electron, ionization may proceed via electron-positron pair creation. The cross section for this channel saturates at several times the threshold energy, and hence the most probable way of photoionizing an atom at high energy is to make the vacuum spark. We present estimates for the cross section of this "vacuum-assisted photoionization" which proceeds either via direct pair creation on the bound electron or via pair creation on the atomic nucleus binding the inner-shell electron followed by an electron-electron or positron-electron encounter. [S1050-2947(99)05204-X]. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Aarhus Univ, Inst Phys & Astron, DK-8000 Aarhus C, Denmark. RP Ionescu, DC (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, 1 Cyclotron Rd, Berkeley, CA 94720 USA. NR 36 TC 14 Z9 14 U1 2 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 MAY PY 1999 VL 59 IS 5 BP 3527 EP 3537 DI 10.1103/PhysRevA.59.3527 PG 11 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 197UB UT WOS:000080383100051 ER PT J AU Riley, ME Ritchie, B AF Riley, ME Ritchie, B TI Numerical time-dependent Schrodinger description of charge-exchange collisions SO PHYSICAL REVIEW A LA English DT Article ID ELECTRON-TRANSFER; CROSS-SECTIONS; HYDROGEN; EQUATION; IONIZATION; EXCITATION; HE-2++H AB An implicit fast Fourier transform algorithm is implemented to solve the time-dependent Schrodinger equation with application to charge-exchange collisions. Cross sections are calculated for He2+ on H and compared with experiment and other theoretical results. A disagreement between previously published theoretical results is resolved. [S1050-2937(99)01 605-4]. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Riley, ME (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 19 TC 28 Z9 33 U1 1 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD MAY PY 1999 VL 59 IS 5 BP 3544 EP 3547 DI 10.1103/PhysRevA.59.3544 PG 4 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 197UB UT WOS:000080383100053 ER PT J AU Kolakowska, A Pindzola, MS Schultz, DR AF Kolakowska, A Pindzola, MS Schultz, DR TI Total electron loss, charge transfer, and ionization in proton-hydrogen collisions at 10-100 keV SO PHYSICAL REVIEW A LA English DT Article ID DEPENDENT SCHRODINGER-EQUATION; ION-ATOM COLLISIONS; HARTREE-FOCK THEORY; NUMERICAL-SOLUTION; ANTIPROTONS; EXCITATION; H+ AB A three-dimensional lattice solution of the time-dependent Schrodinger equation for low quantum states (n less than or equal to 3) is combined with classical trajectory Monte Carlo results for high quantum states (n greater than or equal to 4) to predict total electron loss and total charge-transfer cross sections for proton collisions with atomic hydrogen at intermediate energies. The total charge-transfer cross sections range from 5% above to 10% below the furnace target measurements of McClure [Phys. Rev. 148, 47 (1966)], while the total electron-loss cross sections range from 5% to 15% above the pulsed crossed-beams measurements of Shah, Elliot, and Gilbody [J. Phys. B 20, 3501 (1987)]. The calculation of ionization as a difference between electron loss and charge transfer leads to theoretical ionization cross sections that are 10% to 35% larger than the crossed-beams measurements of Shah and Gilbody [J. Phys. B 14, 2361 (1981)] and Shah, Elliott, and Gilbody [J. Phys. B 20, 2481 (1987)]. [S1050-2947(99)08805-8]. C1 Auburn Univ, Dept Phys, Auburn, AL 36849 USA. Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. RP Kolakowska, A (reprint author), Auburn Univ, Dept Phys, Auburn, AL 36849 USA. NR 14 TC 38 Z9 38 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD MAY PY 1999 VL 59 IS 5 BP 3588 EP 3591 DI 10.1103/PhysRevA.59.3588 PG 4 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 197UB UT WOS:000080383100060 ER PT J AU Larson, A Orel, AE AF Larson, A Orel, AE TI Dissociative recombination of HeH+: Product distributions and ion-pair formation SO PHYSICAL REVIEW A LA English DT Article ID MATRIX ELEMENTS; CROSS-SECTIONS; EXCITATION; STATE; (HEH+)-HE-4; MOLECULE AB We present calculated total cross sections and product state distributions for the dissociative recombination of HeH+ with electrons in the high-energy resonance region. The dissociation dynamics were calculated by the solution of the time-dependent Schrodinger equation for seven coupled resonance states. The resonance curves and autoionization widths were obtained from a complex Kohn variational calculation. We compare several models for the nonadiabatic coupling. The effect of different isotopic combinations of the HeH+ ion on the total and partial cross sections is examined, and a prediction of the cross section for ion-pair formation is made. [S1050-2947(99)09405-6]. C1 Univ Calif Lawrence Livermore Natl Lab, Dept Appl Sci, Livermore, CA 94550 USA. Free Univ Berlin, Inst Phys & Theoret Chem, D-14195 Berlin, Germany. Royal Inst Technol, Dept Phys, S-10044 Stockholm, Sweden. RP Orel, AE (reprint author), Free Univ Berlin, Inst Phys & Theoret Chem, Takustasse 3, D-14195 Berlin, Germany. NR 27 TC 33 Z9 33 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 MAY PY 1999 VL 59 IS 5 BP 3601 EP 3608 DI 10.1103/PhysRevA.59.3601 PG 8 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 197UB UT WOS:000080383100062 ER PT J AU Johnson, WR Derevianko, A Cheng, KT Dolmatov, VK Manson, ST AF Johnson, WR Derevianko, A Cheng, KT Dolmatov, VK Manson, ST TI Nondipole effects in the photoionization of neon: Random-phase approximation SO PHYSICAL REVIEW A LA English DT Article ID PHOTOELECTRON-ANGULAR-DISTRIBUTION; DISTRIBUTION PARAMETERS AB The random-phase approximation (RPA) is applied to study nondipole corrections to the angular distribution of photoelectrons from the n = 2 shell of Ne. Calculations of the parameters gamma(nl) and delta(nl) arising from E-1-E-2 interference effects are carried out for the 2s and 2p subshells of Ne in the photon energy range 100-2000 eV. For the 2s shell, the RPA calculations show small effects of correlation near the 2s threshold energy, but are otherwise in agreement with independent-particle approximation (IPA) calculations. The RPA and TPA values of gamma(2s) are also in agreement with experiment. For the 2p shell, a small difference between RPA and IPA calculations of the nondipole parameters is found for energies near the Is threshold; however, both RPA and IPA calculations of the parameter gamma(2p) + 3 delta(2p) disagree significantly with experimental measurements for photon energies above 1000 eV. [S1050-2947(99)09605-5]. C1 Univ Notre Dame, Dept Phys, Notre Dame, IN 46556 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Georgia State Univ, Dept Phys & Astron, Atlanta, GA 30303 USA. RP Johnson, WR (reprint author), Univ Notre Dame, Dept Phys, Notre Dame, IN 46556 USA. RI Derevianko, Andrei/G-8356-2011; OI Dolmatov, Valeriy/0000-0001-9040-9990 NR 16 TC 38 Z9 38 U1 1 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 MAY PY 1999 VL 59 IS 5 BP 3609 EP 3613 DI 10.1103/PhysRevA.59.3609 PG 5 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 197UB UT WOS:000080383100063 ER PT J AU Jackson, K Pederson, M Wang, CZ Ho, KM AF Jackson, K Pederson, M Wang, CZ Ho, KM TI Calculated polarizabilities of intermediate-size Si clusters SO PHYSICAL REVIEW A LA English DT Article ID GENERALIZED GRADIENT APPROXIMATION; SILICON CLUSTERS; SEMICONDUCTOR CLUSTERS; METAL-CLUSTERS; SPECTRA; SOLIDS; RAMAN AB We have used a first-principles, density-functional-based method to calculate the electric polarizabilities and dipole moments for several low-energy geometrics of Si clusters in the size range 10 less than or equal to N less than or equal to 20. The polarizability per atom is found to be a slowly varying, nonmonotonic function of N. Over this size range the polarizability appears to be correlated most strongly to cluster shape and not with either the dipole moment or the highest occupied-lowest unoccupied molecular-orbital gap. The calculations indicate that the polarizability per atom for Si clusters approaches the bulk limit from above as a function of size. [S1050-2947(99)07305-9]. C1 Cent Michigan Univ, Dept Phys, Mt Pleasant, MI 48859 USA. USN, Res Lab, Complex Syst Theory Branch, Washington, DC 20375 USA. Iowa State Univ Sci & Technol, Ames Lab, US Dept Energy, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Ames Lab, Dept Phys & Astron, Ames, IA 50011 USA. RP Cent Michigan Univ, Dept Phys, Mt Pleasant, MI 48859 USA. OI Jackson, Koblar/0000-0002-5342-7978 NR 24 TC 64 Z9 64 U1 0 U2 3 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 EI 1094-1622 J9 PHYS REV A JI Phys. Rev. A PD MAY PY 1999 VL 59 IS 5 BP 3685 EP 3689 DI 10.1103/PhysRevA.59.3685 PG 5 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 197UB UT WOS:000080383100073 ER PT J AU Fleischhauer, M Unanyan, R Shore, BW Bergmann, K AF Fleischhauer, M Unanyan, R Shore, BW Bergmann, K TI Coherent population transfer beyond the adiabatic limit: Generalized matched pulses and higher-order trapping states SO PHYSICAL REVIEW A LA English DT Article ID QUANTUM STATES; SYSTEMS; HISTORIES; PASSAGE AB We show that the physical mechanism of population transfer in a three-level system with a closed loop of coherent couplings is not equivalent to an adiabatic rotation of the dark state of the Hamiltonian, but corresponds to a rotation of a higher-order trapping state in a generalized adiabatic basis. The concept of generalized adiabatic basis sets is used as a constructive tool to design pulse sequences for stimulated Raman adiabatic passage, which also give maximum population transfer under conditions when the usual condition of adiabaticty is only poorly fulfilled. Under certain conditions for the pulses (generalized matched pulses), there exists a higher-order trapping state, which is an exact constant of motion, and analytic solutions for the atomic dynamics can be derived. [S1050-2947(99)05105-7]. C1 Univ Munich, Sekt Phys, D-80333 Munich, Germany. Univ Kaiserslautern, Fachbereich Phys, D-67663 Kaiserslautern, Germany. Armenian Acad Sci, Inst Phys Res, Ashtarak 378410, Armenia. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Fleischhauer, M (reprint author), Univ Munich, Sekt Phys, D-80333 Munich, Germany. RI Fleischhauer, Michael/G-6716-2011; BERGMANN, KLAAS/D-5543-2011 NR 16 TC 17 Z9 17 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 MAY PY 1999 VL 59 IS 5 BP 3751 EP 3760 DI 10.1103/PhysRevA.59.3751 PG 10 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 197UB UT WOS:000080383100082 ER PT J AU Friar, JL Martorell, J Sprung, DWL AF Friar, JL Martorell, J Sprung, DWL TI Hadronic vacuum polarization and the Lamb shift SO PHYSICAL REVIEW A LA English DT Article AB Recent improvements in the determination of the running of the fine-structure constant also allow an update of the hadronic vacuum-polarization contribution to the Lamb shift. We find a shift of -3.40(7) kHz to the 1S level of hydrogen. We also comment on the contribution of this effect to the determination by elastic electron scattering of the rms radii of nuclei. [S1050-2947(99)06305-2]. C1 Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Univ Barcelona, Fac Fis, Dept Estructura & Constituents Mat, E-08028 Barcelona, Spain. McMaster Univ, Dept Phys & Astron, Hamilton, ON L8S 4M1, Canada. RP Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. NR 12 TC 40 Z9 40 U1 0 U2 0 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 MAY PY 1999 VL 59 IS 5 BP 4061 EP 4063 DI 10.1103/PhysRevA.59.4061 PG 3 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 197UB UT WOS:000080383100118 ER PT J AU Morgan, DV Bartlett, RJ AF Morgan, DV Bartlett, RJ TI Single-photon ionization of helium from 4.5 to 12 keV by Compton scattering and the photoelectric effect SO PHYSICAL REVIEW A LA English DT Article ID K-EDGE REGION; DOUBLE PHOTOIONIZATION; EXCITATION-IONIZATION; MULTIPLE IONIZATION; RATIO; HE AB We have measured the ratio of the cross sections for double-to-single ionization in helium for several monoenergetic photon energies between 4.5 and 12 keV using time-of-flight ion charge state spectroscopy. In this energy range, both the photoelectric effect and inelastic (Compton) scattering contribute significantly to the total cross section. The ionization states caused by Compton scattering were distinguished from those caused by the photoelectric effect by the different recoil energies of the helium ion associated with the two processes. The ratios of the double-to-single ionization cross sections of helium far the photoelectric effect (R-p) and for Compton scattering (R-c) are given, and compared with previous measurements and theoretical calculations. The measured value for R-c at 12 keV is (1.21 +/- 0.27) %, which agrees well with the theoretical calculations of Andersson and Burgdorfer [Phys. Rev. A 50, R2810 (1994)].[S1050-2947(99)05905-3]. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Morgan, DV (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 21 TC 8 Z9 8 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD MAY PY 1999 VL 59 IS 5 BP 4075 EP 4078 DI 10.1103/PhysRevA.59.4075 PG 4 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 197UB UT WOS:000080383100122 ER PT J AU Lamoreaux, SK AF Lamoreaux, SK TI Calculation of the Casimir force between imperfectly conducting plates SO PHYSICAL REVIEW A LA English DT Article AB The Lifshitz formalism for determining the attractive force between material bodies with generalized electromagnetic susceptibility is applied numerically to gold, copper, and aluminum. The deviation from the perfect conductivity Casimir force approximately agrees with a first-order plasma model calculation at large separation, but at separations corresponding to the plasma frequency, deviations of over 50% from the first order model are found, while deviations from corrections up to second order are about 10%. These results are discussed in the context of recent measurements of the Casimir force. [S1050-2947(99)50605-7]. PACS number(s): 12.20.Fv, 07.07.Mp. C1 Univ Calif Los Alamos Natl Lab, Phys Div 23, Los Alamos, NM 87545 USA. RP Lamoreaux, SK (reprint author), Univ Calif Los Alamos Natl Lab, Phys Div 23, MS H803, Los Alamos, NM 87545 USA. NR 15 TC 51 Z9 51 U1 1 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD MAY PY 1999 VL 59 IS 5 BP R3149 EP R3153 DI 10.1103/PhysRevA.59.R3149 PG 5 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 197UB UT WOS:000080383100001 ER PT J AU Zweiback, J Ditmire, T Perry, MD AF Zweiback, J Ditmire, T Perry, MD TI Femtosecond time-resolved studies of the dynamics of noble-gas cluster explosions SO PHYSICAL REVIEW A LA English DT Article ID INTENSE LASER-PULSES; X-RAY-EMISSION; ATOMIC CLUSTERS; ABSORPTION; SCATTERING AB We have examined the dynamics of noble-gas clusters, heated with high-intensity laser radiation, using pump-probe experiments to temporally resolve the expansion of the clusters. Absorption of the probe radiation is observed to reach a maximum for a particular time delay between pump and probe, dependent on the cluster size. For single-pulse experiments, we find that there is an optimal pulse width to maximize absorption for a given cluster size. Model calculations suggest that these effects are due to resonant heating of the spherical cluster plasma in full support of a hydrodynamic interpretation of cluster interactions. [S1050-2917(99)51005-6]. PACS number(s): 36.10.Gk. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Zweiback, J (reprint author), Univ Calif Lawrence Livermore Natl Lab, 7000 East Ave,POB 808 L-477, Livermore, CA 94550 USA. NR 21 TC 88 Z9 88 U1 2 U2 10 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 MAY PY 1999 VL 59 IS 5 BP R3166 EP R3169 DI 10.1103/PhysRevA.59.R3166 PG 4 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA 197UB UT WOS:000080383100005 ER PT J AU Malis, O Ludwig, KF Schweika, W Ice, GE Sparks, CJ AF Malis, O Ludwig, KF Schweika, W Ice, GE Sparks, CJ TI Temperature dependence of the diffuse-scattering fine structure in equiatomic CuAu SO PHYSICAL REVIEW B LA English DT Article ID INTENSITY; CU3AU; ALLOYS; ORDER; AU AB The temperature dependence of the diffuse-scattering fine structure from disordered equiatomic CuAu is studied using in situ x-ray scattering. In contrast to Cu3Au the diffuse peak splitting in CuAu is found to be relatively insensitive to temperature. Consequently, no evidence for a divergence of the antiphase length-scale at the transition temperature is found. At all temperatures studied the peak splitting is smaller than the value corresponding to the CuAuII modulated phase. An extended Ginzburg-Landau approach is used to analyze the temperature dependence of the diffuse peak profiles in the ordering and modulation directions. The estimated mean-field instability point is considerably lower than is the case for Cu,Au. [S0163-1829(99)02118-9]. C1 Boston Univ, Dept Phys, Boston, MA 02215 USA. Forschungszentrum Julich, Julich, Germany. Oak Ridge Natl Lab, Oak Ridge, TN 37830 USA. RP Malis, O (reprint author), Boston Univ, Dept Phys, Boston, MA 02215 USA. NR 15 TC 2 Z9 2 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 MAY 1 PY 1999 VL 59 IS 17 BP 11105 EP 11108 DI 10.1103/PhysRevB.59.11105 PG 4 WC Physics, Condensed Matter SC Physics GA 272CA UT WOS:000084631900001 ER PT J AU Norman, MR Randeria, M Ding, H Campuzano, JC AF Norman, MR Randeria, M Ding, H Campuzano, JC TI Photoelectron escape depth and inelastic secondaries in high-temperature superconductors SO PHYSICAL REVIEW B LA English DT Article AB We calculate the photoelectron escape depth in the high-temperature superconductor Bi2212 by use of electron energy-loss spectroscopy data. We find that the escape depth is only 3 Angstrom for photon energies typically used in angle-resolved photoemission measurements. We then use this to estimate the number of inelastic secondaries, and find this to be quite small near the Fermi energy. This implies that the large background seen near the Fermi energy in photoemission measurements is of some other origin. [S0163-1829(99)08017-0]. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Tata Inst Fundamental Res, Bombay 400005, Maharashtra, India. Univ Illinois, Dept Phys, Chicago, IL 60607 USA. RP Norman, MR (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Norman, Michael/C-3644-2013; OI Ding, Hong/0000-0003-4422-9248 NR 5 TC 19 Z9 19 U1 1 U2 6 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 1999 VL 59 IS 17 BP 11191 EP 11192 DI 10.1103/PhysRevB.59.11191 PG 2 WC Physics, Condensed Matter SC Physics GA 272CA UT WOS:000084631900024 ER PT J AU Kamppeter, T Mertens, FG Moro, E Sanchez, A Bishop, AR AF Kamppeter, T Mertens, FG Moro, E Sanchez, A Bishop, AR TI Stochastic vortex dynamics in two-dimensional easy-plane ferromagnets: Multiplicative versus additive noise SO PHYSICAL REVIEW B LA English DT Article ID ANISOTROPIC HEISENBERG-MODEL; ANTIFERROMAGNET BANI2(PO4)2; NEUTRON-SCATTERING; LANGEVIN-DYNAMICS; MAGNETIC VORTICES; EXCITATIONS; EQUATIONS; MOTION; PERTURBATIONS; DISSIPATION AB We study how thermal fluctuations affect the dynamics of vortices in the two-dimensional classical, ferromagnetic, anisotropic Heisenberg model depending on their additive or multiplicative character. Using a collective coordinate theory, we analytically show that multiplicative noise, arising from fluctuations in the local-field term of the Landau-Lifshitz equations, and Langevin-Like additive noise both have the same effect on vortex dynamics (within a very plausible assumption consistent with the collective coordinate approach). This is a nontrivial result, as multiplicative and additive noises usually modify the dynamics quite differently. We also carry out numerical simulations of both versions of the model finding that they indeed give rise to very similar vortex dynamics. [S0163-1829(99)03917-X]. C1 Univ Bayreuth, Inst Phys, D-95440 Bayreuth, Germany. Univ Carlos III Madrid, Dept Matemat, Grp Interdisciplinar Sistemas Complicados, E-28911 Madrid, Spain. 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 Kamppeter, T (reprint author), Univ Bayreuth, Inst Phys, POB 101251, D-95440 Bayreuth, Germany. EM till.kamppeter@theo.phy.uni-bayreuth.de; franz.mertens@theo.phy.uni-bayreuth.de; emoro@math.uc3m.es; anxo@math.uc3m.es; arb@viking.lanl.gov RI Sanchez, Angel/A-9229-2008; OI Sanchez, Angel/0000-0003-1874-2881; MORO, ESTEBAN/0000-0003-2894-1024 NR 42 TC 23 Z9 23 U1 1 U2 4 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 1999 VL 59 IS 17 BP 11349 EP 11357 DI 10.1103/PhysRevB.59.11349 PG 9 WC Physics, Condensed Matter SC Physics GA 272CA UT WOS:000084631900049 ER PT J AU Barnes, T Riera, J Tennant, DA AF Barnes, T Riera, J Tennant, DA TI S=(1)/(2) alternating chain using multiprecision methods SO PHYSICAL REVIEW B LA English DT Article ID SPIN-PEIERLS COMPOUND; SINGLET-GROUND-STATE; MAGNETIC EXCITATIONS; NEUTRON-SCATTERING; SERIES EXPANSIONS; LATTICE MODELS; PHASE-DIAGRAM; CUGEO3; SUSCEPTIBILITY; SPECTRUM AB In this paper we present results for the ground state and low-lying excitations of the S=1/2 alternating Heisenberg antiferromagnetic chain. Our more conventional techniques include perturbation theory about the dimer limit and numerical diagonalization of systems of up to 28 spins. An application of multiple precision numerical diagonalization allows us to determine analytical perturbation series to high order; the results found using this approach include ninth-order perturbation series for the ground state energy and one magnon gap. We also determine the fifth-order dispersion relation and third-order exclusive neutron scattering structure factor for one-magnon modes and numerical and analytical binding energies of S=0 and S=1 two-magnon bound states. [S0163-1829(99)02917-3]. C1 Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. Inst Fis Rosario, RA-2000 Rosario, Santa Fe, Argentina. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Barnes, T (reprint author), Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. RI Riera, Jose/A-1234-2008; Tennant, David/Q-2497-2015 OI Riera, Jose/0000-0003-4546-1137; Tennant, David/0000-0002-9575-3368 NR 53 TC 96 Z9 96 U1 2 U2 4 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 1999 VL 59 IS 17 BP 11384 EP 11397 DI 10.1103/PhysRevB.59.11384 PG 14 WC Physics, Condensed Matter SC Physics GA 272CA UT WOS:000084631900053 ER PT J AU Hellman, F Shapiro, AL Abarra, EN Robinson, RA Hjelm, RP Seeger, PA Rhyne, JJ Suzuki, JI AF Hellman, F Shapiro, AL Abarra, EN Robinson, RA Hjelm, RP Seeger, PA Rhyne, JJ Suzuki, JI TI Long ferromagnetic correlation length in amorphous TbFe2 SO PHYSICAL REVIEW B LA English DT Article ID RANDOM-ANISOTROPY MAGNETS; MEAN-FIELD ANALYSIS; EXTENDED ORIENTATIONAL ORDER; TRANSITION-METAL-ALLOYS; RARE-EARTH ALLOYS; TB-FE FILMS; NEUTRON-SCATTERING; PHASE-TRANSITIONS; HEISENBERG MODELS; RANGE ORDER AB Small-angle neutron scattering (SANS) and magnetic-force microscopy (MFM) have been used to characterize the temperature dependence of the ferromagnetic correlation length and the domain structure in amorphous TbFe2 below its magnetic ordering temperature. Amorphous TbFe2 is classified as a random anisotropy magnet, in the exchange-dominated limit, and previous SANS observations had shown a correlation length limited to 50 Angstrom at low temperatures. In the present study, samples were prepared by both sputtering and electron beam coevaporation and were either grown or preannealed at 200 degrees C in order to permit measurements above T-c without structural relaxation. Samples grown by vapor deposition processes possess a large macroscopic perpendicular anisotropy constant K-u, which can be reduced or eliminated by annealing. A strong SANS signal is seen in all samples, with a magnitude strongly correlated with the temperature-dependent sample magnetization and with the inverse length scale of the domain structure seen in MFM. For all samples, the magnetic correlation length determined from SANS is 300-500 Angstrom in the thermally demagnetized state, and increases beyond measurement range after magnetizing. This long correlation length is consistent with theoretical predictions of a ferromagnetic ground state in exchange-dominated random anisotropy magnets in the presence of coherent anisotropy. The SANS signal is dominated by a Lorentzian squared term, which is best understood as resulting from ferromagnetic domains with meandering domain walls, similar to the Debye-Bueche model developed for materials consisting of two strongly segregated, interpenetrating phases. [S0163-1829(99)01317-X]. C1 Univ Calif San Diego, Dept Phys, La Jolla, CA 92093 USA. Toyota Technol Inst, Nagoya, Aichi 468, Japan. Univ Calif Los Alamos Natl Lab, Manuel Lujan Jr Neutron Scattering Ctr, Los Alamos, NM 87545 USA. Univ Missouri, Dept Phys, Columbia, MO 65211 USA. Japan Atom Energy Res Inst, Tokai, Ibaraki 31911, Japan. RP Hellman, F (reprint author), Univ Calif San Diego, Dept Phys, La Jolla, CA 92093 USA. RI Lujan Center, LANL/G-4896-2012 NR 58 TC 39 Z9 39 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 MAY 1 PY 1999 VL 59 IS 17 BP 11408 EP 11417 DI 10.1103/PhysRevB.59.11408 PG 10 WC Physics, Condensed Matter SC Physics GA 272CA UT WOS:000084631900055 ER PT J AU Zheludev, A Maslov, S Shirane, G Tsukada, I Masuda, T Uchinokura, K Zaliznyak, I Erwin, R Regnault, LP AF Zheludev, A Maslov, S Shirane, G Tsukada, I Masuda, T Uchinokura, K Zaliznyak, I Erwin, R Regnault, LP TI Magnetic anisotropy and low-energy spin waves in the Dzyaloshinskii-Moriya spiral magnet Ba2CuGe2O7 SO PHYSICAL REVIEW B LA English DT Article ID FIELD; ANTIFERROMAGNET; COMMENSURATE; PHASE; SCATTERING; TRANSITION; ORBIT; MNSI AB Neutron-diffraction and inelastic-scattering experiments are used to investigate in detail the field dependence of the magnetic structure and low-energy spin-wave spectrum of the Dzyaloshinskii-Moriya helimagnet Ba2CuGe2O7. The results suggest that the previously proposed model for the magnetism of this compound (an ideal sinusoidal spin spiral, stabilized by isotropic exchange and Dzyaloshinskii-Moriya interactions) needs to be refined. Both recent and previously published data can be quantitatively explained by taking into account the Kaplan-Shekhtman-Entin-Wohlman-Aharony term, a special magnetic anisotropy term that was predicted to always accompany Dzyaloshinskii-Moriya interactions in insulators. [S0163-1829(99)01017-6]. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. Univ Tokyo, Dept Appl Phys, Bunkyo Ku, Tokyo 1138656, Japan. Natl Inst Stand & Technol, Ctr Neutron Res, Gaithersburg, MD 20899 USA. Ctr Etud Nucl Grenoble, Dept Rech Fondamentale Mat Condensee, Lab Magnetisme & Diffract Neutron, F-38054 Grenoble, France. Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. PL Kapitza Phys Problems Inst, Moscow, Russia. RP Zheludev, A (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. RI Zaliznyak, Igor/E-8532-2014; Maslov, Sergei/C-2397-2009 OI Zaliznyak, Igor/0000-0002-9886-3255; Maslov, Sergei/0000-0002-3701-492X NR 25 TC 43 Z9 43 U1 1 U2 18 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 MAY 1 PY 1999 VL 59 IS 17 BP 11432 EP 11444 DI 10.1103/PhysRevB.59.11432 PG 13 WC Physics, Condensed Matter SC Physics GA 272CA UT WOS:000084631900058 ER PT J AU Tsuchiya, Y Hanaguri, T Yasuda, H Maeda, A Sasase, M Hojou, K Steel, DG Lee, JU Hofman, DJ AF Tsuchiya, Y Hanaguri, T Yasuda, H Maeda, A Sasase, M Hojou, K Steel, DG Lee, JU Hofman, DJ TI Interlayer phase correlation of the vortex system around the coupling transition in Bi2Sr2CaCu2Oy containing columnar defects SO PHYSICAL REVIEW B LA English DT Article ID JOSEPHSON PLASMA RESONANCE; HIGH-TEMPERATURE SUPERCONDUCTORS; SINGLE-CRYSTALS; STATE; DISORDER; DYNAMICS; LIQUID AB The Josephson plasma resonance and de magnetization were,investigated in a high-T-c cuprate Bi2Sr2CaCu2Oy (Bi-2212) containing columnar defects in order to clarify the detailed behavior in the reversible region around the coupling transition of pancake vortices. We point out that the coupling transition line which separates decoupled and well-coupled pancake vortices is a temperature independent horizontal line on the H-T plane. This result indicates that the coupling transition is a field-induced phenomenon. We find that the rapid reduction of the interlayer phase correlation and the enhancement of the in-plane critical current density take place simultaneously at B=B*, which is just below the coupling transition field B-cp. This phenomenon may be interpreted as the field-induced acceleration of the decoupling of pancake vortices in the reversible region bf Bi-2212 with columnar defects. B-cp was rather smaller than B phi. From transmission electron microscopy, we infer that the inhomogeneous distribution of columnar defects may be related to the coupling transition field B(cp)similar to B-phi(eff), which was rather smaller than B-phi. [S0163-1829(99)09117-1]. C1 Univ Tokyo, Dept Basic Sci, Meguro Ku, Tokyo 1538902, Japan. Japan Sci & Technol Corp, CREST, Kawaguchi 3320012, Japan. Japan Atom Energy Res Inst, Tokai, Ibaraki 3191195, Japan. Argonne Natl Lab, Div Sci Mat, Argonne, IL 60439 USA. Argonne Natl Lab, Div Phys, ATLAS Accelerator, Argonne, IL 60439 USA. RP Tsuchiya, Y (reprint author), Univ Tokyo, Dept Basic Sci, Meguro Ku, 3-8-1 Komaba, Tokyo 1538902, Japan. RI Hanaguri, Tetsuo/I-6710-2012; Tsuchiya, Yoshishige/B-6127-2013 OI Hanaguri, Tetsuo/0000-0003-2896-0081; NR 25 TC 8 Z9 8 U1 1 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 MAY 1 PY 1999 VL 59 IS 17 BP 11568 EP 11574 DI 10.1103/PhysRevB.59.11568 PG 7 WC Physics, Condensed Matter SC Physics GA 272CA UT WOS:000084631900074 ER PT J AU Artemenko, SN Bulaevskii, LN Maley, MP Vinokur, VM AF Artemenko, SN Bulaevskii, LN Maley, MP Vinokur, VM TI Effect of quasiparticles on interlayer transport in highly anisotropic layered superconductors SO PHYSICAL REVIEW B LA English DT Article ID JOSEPHSON PLASMA RESONANCE; COUPLED SUPERCONDUCTORS; VORTEX LIQUID; PENETRATION DEPTH; SINGLE-CRYSTALS; TUNNELING MODEL; BI2SR2CACU2O8+DELTA; OSCILLATIONS; STATE; MAGNETORESISTANCE AB We have performed a microscopic calculation of the dielectric response function in highly anisotropic layered superconductors and used the developed approach to obtain the frequency-dependent London penetration length and conductivity in the case of d-wave pairing for currents perpendicular to the layers. We consider a BCS model with coherent interlayer tunneling of electrons and take into account contributions from both superconducting electrons and quasiparticles to the dielectric response. We show that quasiparticles change the low-temperature behavior of the penetration length in the intermediate frequency range where the frequency is smaller than the superconducting order parameter but larger than the inverse quasiparticle scattering time. The obtained results are used to describe the low-temperature behavior of the Josephson plasma resonance, in particular the temperature dependence of the resonance frequency and the resonance linewidth in zero external magnetic field. We compare our results with the available experimental data for Tl2Ba2CuO6 and Bi2Sr2CaCu2O8+delta (Bi-2212) and show that results of a BCS model with coherent interlayer tunneling for the de c-axis resistivity in the superconducting state are inconsistent with experimental data for underdoped and optimally doped Bi-2212 crystals. [S0163-1829(99)04917-6]. C1 Russian Acad Sci, Inst Radioengn & Elect, Moscow 103907, Russia. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Artemenko, SN (reprint author), Russian Acad Sci, Inst Radioengn & Elect, Moscow 103907, Russia. NR 35 TC 9 Z9 9 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 1999 VL 59 IS 17 BP 11587 EP 11595 DI 10.1103/PhysRevB.59.11587 PG 9 WC Physics, Condensed Matter SC Physics GA 272CA UT WOS:000084631900077 ER PT J AU Liu, W Johnson, WL Schneider, S Geyer, U Thiyagarajan, P AF Liu, W Johnson, WL Schneider, S Geyer, U Thiyagarajan, P TI Small-angle x-ray-scattering study of phase separation and crystallization in the bulk amorphous Mg62Cu25Y10Li3 alloy SO PHYSICAL REVIEW B LA English DT Article ID NEUTRON-SCATTERING; CASTING METHOD; DECOMPOSITION; NANOCRYSTALS AB We report on a small-angle x-ray-scattering (SAXS) and differential scanning calorimetry study of phase separation and crystallization in rapidly quenched amorphous Mg62Cu25Y10Li3 alloy samples. Differential scanning calorimetry demonstrates the occurrence of crystallization and grain growth upon isothermal annealing of these samples at 135 degrees C. The SAXS studies show the presence of large inhomogeneities even in the rapidly quenched as-prepared Mg62Cu25Y10Li3 alloy that is attributed to phase separation in the undercooled liquid during the cooling process. After isothermal annealing at 135 degrees C for longer than 30 min the samples exhibit a strong SAXS intensity that monotonically increases with increasing annealing time. During heat treatment, crystallization and growth of a nanocrystalline bcc-ME,li,phase occurs in the Y-poor and MgLi-rich domains. The initially rough boundaries of the nanocrystals become sharper with increasing annealing time. Anomalous small-angle x-ray-scattering investigations near the Cu K edge indicate that while Cu is distributed homogeneously in the as-prepared sample, a Cu composition gradient develops between the matrix and the bcc-Mg7Li3 nanocrystals in the annealed sample. [S0163-1829(99)01018-8]. C1 Argonne Natl Lab, Div Intense Pulsed Neutron Source, Argonne, IL 60439 USA. CALTECH, WM Keck Lab Engn Mat, Pasadena, CA 91125 USA. Univ Gottingen, Inst Phys 1, D-37073 Gottingen, Germany. Univ Gottingen, Sonderforsch Bereich 345, D-37073 Gottingen, Germany. RP Thiyagarajan, P (reprint author), Argonne Natl Lab, Div Intense Pulsed Neutron Source, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 22 TC 38 Z9 41 U1 1 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 MAY 1 PY 1999 VL 59 IS 18 BP 11755 EP 11759 DI 10.1103/PhysRevB.59.11755 PG 5 WC Physics, Condensed Matter SC Physics GA 197HN UT WOS:000080359500024 ER PT J AU Smith, AW Jaeger, HM Rosenbaum, TF Kwok, WK Crabtree, GW AF Smith, AW Jaeger, HM Rosenbaum, TF Kwok, WK Crabtree, GW TI Signature of the matching field in Bose-glass melting of untwinned YBa2Cu3O7-delta single crystals SO PHYSICAL REVIEW B LA English DT Article ID HIGH-TEMPERATURE SUPERCONDUCTORS; COLUMNAR DEFECTS; VORTEX; LOCALIZATION; TRANSITION; DENSITY; DEEP; LINE AB We map out the phase boundary separating the Bose-glass and vortex-liquid phases in an irradiated twin-free YBa2Cu3O7-delta single crystal. We take the phase boundary to be the temperature T-g and magnetic field H at which the crystal begins to screen a small ac magnetic field, h(ac). There is a significant change in slope dT(g)/dH of the phase boundary at the matching field B-Phi (similar or equal to 0.5 T) indicating that interstitial vortices significantly weaken pinning in the Bose-glass state. There is also a pronounced peak in the slope dT(g)/dH just below B-Phi at higher h(ac). Both features disappear when the field is tilted away from the columns. [S0163-1829(99)51318-0]. C1 Univ Chicago, James Franck Inst, Dept Phys, Chicago, IL 60637 USA. Argonne Natl Lab, Sci & Technol Ctr Superconduct, Div Sci Mat, Argonne, IL 60439 USA. RP Smith, AW (reprint author), Univ Chicago, James Franck Inst, Dept Phys, 5640 S Ellis Ave, Chicago, IL 60637 USA. NR 17 TC 1 Z9 1 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 MAY 1 PY 1999 VL 59 IS 18 BP R11665 EP R11667 DI 10.1103/PhysRevB.59.R11665 PG 3 WC Physics, Condensed Matter SC Physics GA 197HN UT WOS:000080359500009 ER PT J AU Cromaz, M DeGraaf, J Drake, TE Ward, D Galindo-Uribarri, A Janzen, VP Radford, DC Flibotte, S Mullins, SM Rodriguez, J Pilotte, S AF Cromaz, M DeGraaf, J Drake, TE Ward, D Galindo-Uribarri, A Janzen, VP Radford, DC Flibotte, S Mullins, SM Rodriguez, J Pilotte, S TI High spin spectroscopy of Hf-167 SO PHYSICAL REVIEW C LA English DT Article ID COINCIDENCE DATA SETS; STATES AB Hf-167 was populated at low and high spins via the heavy-ion fusion reactions Gd-155(O-16,4n) at 85 MeV and Nd-146(Mg-26,5n) at 147 MeV, respectively. Seven rotational bands were observed; four of them art: new, and the known bands are extended to much higher spin. A total Routhian surface plus a cranked shell-model calculation enabled quasiparticle configurations to be assigned to the respective bands via comparison with the extracted alignment gains and Routhians from experiment. Evidence is presented for the observation of a quasiproton crossing at h omega=0.51 MeV in Hf-167. The gamma-ray flux appears to fractionate above this frequency. [S0556-2813(99)02405-X]. C1 Univ Toronto, Dept Phys, Toronto, ON M5S 1A7, Canada. AECL Res, Chalk River Labs, Chalk River, ON K0J 1J0, Canada. McMaster Univ, Dept Phys & Astron, Hamilton, ON L8S 4M1, Canada. Univ Strasbourg 1, Ctr Rech Nucl, Inst Natl Phys Nucl & Phys Particules, F-67037 Strasbourg, France. RP Cromaz, M (reprint author), Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RI radford, David/A-3928-2015 NR 18 TC 7 Z9 8 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 MAY PY 1999 VL 59 IS 5 BP 2406 EP 2415 DI 10.1103/PhysRevC.59.2406 PG 10 WC Physics, Nuclear SC Physics GA 197UC UT WOS:000080383200013 ER PT J AU Garrett, PE Lehmann, H Jolie, J McGrath, CA Yeh, MF Yates, SW AF Garrett, PE Lehmann, H Jolie, J McGrath, CA Yeh, MF Yates, SW TI Quadrupole-octupole coupled states in Cd-112 SO PHYSICAL REVIEW C LA English DT Article ID INTERACTING BOSON MODEL; ELECTRIC-DIPOLE TRANSITIONS; 2-PHONON CHARACTER; MULTIPHONON STATES; PARTICLE MULTIPLET; EXCITATIONS; ISOTOPES; NUCLEI; ND-142; N=82 AB The properties of negative-parity states in the 2.5 MeV region in Cd-112 have been investigated with the (n,n' gamma) reaction. For many of these levels, lifetimes have been measured, and B(E1) and B(E2) values for their decays have been determined. Several transitions exhibit enhanced B(E2) values for decay to the 3(1)(-) octupole state, indicative of quadrupole-octupole coupled (2(+)x3(-)) states. The B(E1) values observed are typically in the range of 1-5 x 10(-4) Weisskopf units (W.u.), irrespective of the final state. [S0556-2813(99)08205-9]. C1 Univ Kentucky, Lexington, KY 40506 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Fribourg, Inst Phys, CH-1700 Fribourg, Switzerland. RP Garrett, PE (reprint author), Univ Kentucky, Lexington, KY 40506 USA. RI McGrath, Christopher/E-8995-2013 NR 41 TC 38 Z9 38 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 MAY PY 1999 VL 59 IS 5 BP 2455 EP 2461 DI 10.1103/PhysRevC.59.2455 PG 7 WC Physics, Nuclear SC Physics GA 197UC UT WOS:000080383200019 ER PT J AU Dean, DJ Ressell, MT Hjorth-Jensen, M Koonin, SE Langanke, K Zuker, AP AF Dean, DJ Ressell, MT Hjorth-Jensen, M Koonin, SE Langanke, K Zuker, AP TI Shell-model Monte Carlo studies of neutron-rich nuclei in the 1s-0d-1p-0f shells SO PHYSICAL REVIEW C LA English DT Article ID N = 20; PRACTICAL SOLUTION; PF-SHELL; ISOTOPES; DEFORMATION; REGION; SCATTERING; TRANSITION; STRENGTH; STATE AB We demonstrate the feasibility of realistic shell-model Monte Carlo (SMMC) calculations spanning multiple major shells, using a realistic interaction whose bad saturation and shell properties have been corrected by a newly developed general prescription. Particular attention is paid to the approximate restoration of translational invariance. The model space consists of the full sd-pf shells. We include in the study some well-known T = 0 nuclei and several unstable neutron-rich ones around N= 20,28. The results indicate: that SMMC calculations can reproduce binding energies, B(E2) transitions, and other observables with an interaction that is practically parameter free. Some interesting insight is gained into the nature of deep correlations. The validity of previous studies is confirmed. [S0556-2813(99)00405-7]. C1 Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. CALTECH, WK Kellogg Radiat Lab, Pasadena, CA 91125 USA. NORDITA, DK-2100 Copenhagen O, Denmark. Univ Oslo, Dept Phys, N-0316 Oslo, Norway. Univ Chicago, Ctr Astron & Astrophys, Chicago, IL 60637 USA. Univ Aarhus, Inst Phys & Astron, DK-8000 Aarhus C, Denmark. Univ Strasbourg, CNRS, IN2P3, Inst Rech Subatom, F-67037 Strasbourg 2, France. RP Oak Ridge Natl Lab, Div Phys, POB 2008, Oak Ridge, TN 37831 USA. RI Hjorth-Jensen, Morten/B-1417-2008; OI Dean, David/0000-0002-5688-703X; zuker, andres/0000-0003-0720-3452 NR 52 TC 61 Z9 61 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9985 EI 2469-9993 J9 PHYS REV C JI Phys. Rev. C PD MAY PY 1999 VL 59 IS 5 BP 2474 EP 2486 DI 10.1103/PhysRevC.59.2474 PG 13 WC Physics, Nuclear SC Physics GA 197UC UT WOS:000080383200021 ER PT J AU Ginocchio, JN AF Ginocchio, JN TI Implications of pseudospin symmetry on relativistic magnetic properties and Gamow-Teller transitions in nuclei SO PHYSICAL REVIEW C LA English DT Article ID POTENTIALS; STATES AB Recently it has been shown that pseudospin symmetry has its origins in a relativistic symmetry of the Dirac Hamiltonian. Using this symmetry we relate single-nucleon relativistic magnetic moments of states in a pseudospin doublet to the relativistic magnetic dipole transitions between the states in the doublet, and we relate single-nucleon relativistic Gamow-Teller transitions within states in the doublet. We apply these relationships to the Gamow-Teller transitions from Ca-39 to its mirror nucleus K-39. [S0556-2813(99)01105-X]. C1 Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Ginocchio, JN (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. NR 28 TC 34 Z9 34 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 MAY PY 1999 VL 59 IS 5 BP 2487 EP 2493 DI 10.1103/PhysRevC.59.2487 PG 7 WC Physics, Nuclear SC Physics GA 197UC UT WOS:000080383200022 ER PT J AU Chen, CM Ernst, DJ Johnson, MB AF Chen, CM Ernst, DJ Johnson, MB TI Phenomenology of K+-nucleus scattering SO PHYSICAL REVIEW C LA English DT Article ID TOTAL CROSS-SECTIONS; ELASTIC-SCATTERING; CHARGE-EXCHANGE; OPTICAL-MODEL; MEV/C; WAVE; C-12 AB A density expansion of the K+-nucleus optical potential is used within a momentum-space approach to analyze the experimental total and elastic differential cross section data. We add to the microscopic first-order optical potential a phenomenological higher-order term proportional to the nucleon density raised to a power alpha. A fit to the total cross section data yields a value for alpha of 2.85+/-0.25 and a strength for the potential that decreases slightly faster than the inverse of the kaon laboratory momentum. To obtain a higher-order potential compatible with all the data and with parameters that are target independent, a renormalization of the differential cross section data by 30%, consistent with our estimate of systematic errors, is made. The need for such a large renormalization is explained. [S0556-2813(99)04105-9]. C1 St Johns & St Marys Inst Technol, Taipei 25135, Taiwan. Vanderbilt Univ, Dept Phys & Astron, Nashville, TN 37235 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Chen, CM (reprint author), St Johns & St Marys Inst Technol, Taipei 25135, Taiwan. NR 39 TC 5 Z9 5 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD MAY PY 1999 VL 59 IS 5 BP 2627 EP 2633 DI 10.1103/PhysRevC.59.2627 PG 7 WC Physics, Nuclear SC Physics GA 197UC UT WOS:000080383200038 ER PT J AU Jeschonnek, S Donnelly, TW AF Jeschonnek, S Donnelly, TW TI Spin-orbit final-state interaction in the framework of Glauber theory for (e,e ' p) reactions SO PHYSICAL REVIEW C LA English DT Article ID ELECTRON-SCATTERING; GEV ENERGIES; DEUTERON; POLARIZATION; NUCLEI AB We investigate the reactions D(e,e' p)n and D(e,e' )n at GeV energies and discuss the opportunities to distinguish between different models for the nuclear ground state by measuring the response functions. In calculating the final-state interaction (FSI) we employ Glauber theory, and we also include relativistic effects in the electromagnetic current. We include not only the central FSI, but also the spin-orbit FSI which is usually neglected in (e,e' p) calculations within the Glauber framework, and we show that this contribution plays a crucial role for the fifth response function. All of the methods developed here can be applied to any target nucleus. [S0556-2813(99)07205-2]. C1 Jefferson Lab, Newport News, VA 23606 USA. MIT, Ctr Theoret Phys, Nucl Sci Lab, Cambridge, MA 02139 USA. MIT, Dept Phys, Cambridge, MA 02139 USA. RP Jeschonnek, S (reprint author), Jefferson Lab, 12000 Jefferson Ave, Newport News, VA 23606 USA. OI Jeschonnek, Sabine/0000-0002-8603-7589 NR 22 TC 15 Z9 15 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD MAY PY 1999 VL 59 IS 5 BP 2676 EP 2688 DI 10.1103/PhysRevC.59.2676 PG 13 WC Physics, Nuclear SC Physics GA 197UC UT WOS:000080383200045 ER PT J AU Armstrong, TA Barish, KN Batsoulli, S Bennett, SJ Chikanian, A Coe, SD Cormier, TM Davies, R Dover, CB Fachini, P Fadem, B Finch, LE George, NK Greene, SV Haridas, P Hill, JC Hirsch, AS Hoversten, R Huang, HZ Kumar, BS Lainis, T Lajoie, JG Li, Q Libby, B Majka, RD Miller, TE Munhoz, MG Nagle, JL Pless, IA Pope, JK Porile, NT Pruneau, CA Rabin, MSZ Reid, JD Rimai, A Rose, A Rotondo, FS Sandweiss, J Scharenberg, RP Slaughter, AJ Smith, GA Tincknell, ML Toothacker, WS Van Buren, G Wohn, FK Xu, Z AF Armstrong, TA Barish, KN Batsoulli, S Bennett, SJ Chikanian, A Coe, SD Cormier, TM Davies, R Dover, CB Fachini, P Fadem, B Finch, LE George, NK Greene, SV Haridas, P Hill, JC Hirsch, AS Hoversten, R Huang, HZ Kumar, BS Lainis, T Lajoie, JG Li, Q Libby, B Majka, RD Miller, TE Munhoz, MG Nagle, JL Pless, IA Pope, JK Porile, NT Pruneau, CA Rabin, MSZ Reid, JD Rimai, A Rose, A Rotondo, FS Sandweiss, J Scharenberg, RP Slaughter, AJ Smith, GA Tincknell, ML Toothacker, WS Van Buren, G Wohn, FK Xu, Z CA E864 Collaboration TI Antiproton production and antideuteron production limits in relativistic heavy ion collisions SO PHYSICAL REVIEW C LA English DT Article ID NUCLEUS-NUCLEUS COLLISIONS; MULTIPLICITY DETECTOR; 14.6A GEV/C; PBAR AB We present results from Experiment 864 for antiproton production and antideuteron limits in Au + Pb collisions at 11.5 GeV/e per nucleon. We have measured invariant multiplicities for antiprotons for rapidities 1.4(NU)OVER-BAR(E) OSCILLATIONS; PARAMETRIC-RESONANCE; LSND EXPERIMENT; 3 NEUTRINOS; FLUX; SPECTRUM; EVENTS; PHYSICS AB We determine the three-neutrino mixing and mass parameters that are allowed by the solar and atmospheric neutrino data when vacuum oscillations are responsible for both phenomena. The global fit does not appreciably change the allowed regions for the parameters obtained from effective two-neutrino fits. We discuss how measurements of the solar electron energy spectrum below 6.5 GeV in Super-Kamiokande and seasonal variations in the Super-Kamiokande, Ga-71, and BOREXINO experiments can distinguish the different solar vacuum solutions. [S0556-2821(99)09009-8]. C1 Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Wisconsin, Dept Phys, Madison, WI 53706 USA. RP Fermilab Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. NR 136 TC 42 Z9 42 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 MAY 1 PY 1999 VL 59 IS 9 AR 093007 DI 10.1103/PhysRevD.59.093007 PG 13 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 193BC UT WOS:000080114600018 ER PT J AU Bergmann, S Grossman, Y AF Bergmann, S Grossman, Y TI Can lepton flavor violating interactions explain the LSND results? art. no. 093005 SO PHYSICAL REVIEW D LA English DT Article ID NEUTRINO OSCILLATION EXPERIMENTS; STERILE NEUTRINO; MODELS; SOLAR; PHYSICS; CURRENTS; REACTOR; PUZZLES; FERMION; MUONIUM AB If the atmospheric and the solar neutrino problems are both explained by neutrino oscillations, and if there are only three light neutrinos, then all mass-squared differences between the neutrinos are known. In such a case, existing terrestrial neutrino oscillation experiments cannot be significantly affected by neutrino oscillations, but, in principle there could be an anomaly in the neutrino flux due to new neutrino interactions. We discuss how a non-standard muon decay mu+-->e+<(nu)over bar>(e)nu(l) would modify the neutrino production processes of these experiments. Since SU(2)(L) violation is small for new physics above the weak scale one can use related flavor-violating charged lepton processes to constrain these decays in a model independent way. We show that the upper bounds on mu-->3e, muonium-antimuonium conversion and tau-->mu ee rule out any observable effect for the present experiments due to mu(+)-->e(+)<(nu)over bar>(e)nu(l) for l = e, mu, tau, respectively. Applying similar arguments to flavor-changing semi-leptonic reactions we exclude the possibility that the "oscillation signals" observed at LSND are due to flavor-changing interactions that conserve total lepton number. [S0556-2821(99)04409-4]. C1 Weizmann Inst Sci, Dept Particle Phys, IL-76100 Rehovot, Israel. Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Weizmann Inst Sci, Dept Particle Phys, IL-76100 Rehovot, Israel. OI Bergmann, Sven/0000-0002-6785-9034 NR 54 TC 53 Z9 53 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 MAY 1 PY 1999 VL 59 IS 9 AR 093005 DI 10.1103/PhysRevD.59.093005 PG 11 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 193BC UT WOS:000080114600016 ER PT J AU De Gouvea, A Friedland, A Murayama, H AF De Gouvea, A Friedland, A Murayama, H TI Less minimal supersymmetric standard model SO PHYSICAL REVIEW D LA English DT Article ID SYMMETRY-BREAKING AB Most of the phenomenological studies of supersymmetry have been carried out using the so-called minimal supergravity scenario, where one assumes a universal scalar mass, gaugino mass, and trilinear coupling at M-GUT. Even though this is a useful simplifying assumption, it is too restrictive to accommodate a large variety of phenomenological possibilities. It predicts that the lightest supersymmetric particle (LSP) is an almost pure B-ino. We extend the minimal scenario by introducing one extra parameter: the Fayet-Iliopoulos D term for U(1)(Y), D-Y, and find a much more diverse phenomenology, where the LSP is <(nu)over tilde>(tau), or <(tau)over tilde> Higgsino-like neutralino. We discuss the relevance of the different possibilities to collider signatures. [S0556-2821(99)08709-3]. C1 Univ Calif Berkeley, Ernest Orlando Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. RP De Gouvea, A (reprint author), Univ Calif Berkeley, Ernest Orlando Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RI Murayama, Hitoshi/A-4286-2011 NR 13 TC 30 Z9 30 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD MAY 1 PY 1999 VL 59 IS 9 AR 095008 DI 10.1103/PhysRevD.59.095008 PG 5 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 193BC UT WOS:000080114600064 ER PT J AU Dicus, D Stelzer, T Sullivan, Z Willenbrock, S AF Dicus, D Stelzer, T Sullivan, Z Willenbrock, S TI Higgs-boson production in association with bottom quarks at next-to-leading order SO PHYSICAL REVIEW D LA English DT Article ID HADRON COLLIDERS; HEAVY-QUARK; FERMILAB TEVATRON; MASS; FUSION; QCD; PARTON; MODEL; LHC AB We argue that the leading-order subprocess for Higgs-boson production in association with bottom quarks is b (b) over bar-->H. This process is an important source of Higgs bosons with enhanced Yukawa coupling to bottom quarks. We calculate the corrections to this cross section at next-to-leading-order in 1/ln(m(H)/m(b)) and alpha(s) and at next-to-next-to-leading order in 1/ln(m(H)/m(b)). [S0556-2821(99)06609-6]. C1 Univ Texas, Dept Phys, Ctr Particle Phys, Austin, TX 78712 USA. Univ Illinois, Dept Phys, Urbana, IL 61801 USA. Argonne Natl Lab, Div High Energy Phys, Argonne, IL 60439 USA. Univ Chicago, Enrico Fermi Inst, Chicago, IL 60637 USA. Univ Chicago, Dept Phys, Chicago, IL 60637 USA. RP Univ Texas, Dept Phys, Ctr Particle Phys, Austin, TX 78712 USA. NR 30 TC 103 Z9 103 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 MAY 1 PY 1999 VL 59 IS 9 AR 094016 DI 10.1103/PhysRevD.59.094016 PG 9 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 193BC UT WOS:000080114600036 ER PT J AU 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 Miller, JS 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, HN Nelson, TK Roberts, D Behrens, BH Ford, WT Gritsan, A Krieg, H Roy, J Smith, JG Alexander, JP Baker, R Bebek, C Berger, BE Berkelman, K Boisvert, V Cassel, DG Crowcroft, DS Dickson, M von Dombrowski, S Drell, PS Ecklund, KM Ehrlich, R Foland, AD Gaidarev, P Galik, RS Gibbons, L Gittelman, B Gray, SW Hartill, DL Heltsley, BK Hopman, PI Kreinick, DL Lee, T Liu, Y Meyer, TO Mistry, NB Ng, CR Nordberg, E Ogg, M Patterson, JR Peterson, D Riley, D Soffer, A Thayer, JG Thies, PG Valant-Spaight, B Warburton, A Ward, C Athanas, M Avery, P Jones, CD Lohner, M Prescott, C Rubiera, AI Yelton, J Zheng, J Brandenburg, G Briere, RA 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 Selen, M Thaler, JJ Edwards, KW Bellerive, A Janicek, R Patel, PM Sadoff, AJ Ammar, R Baringer, P Bean, A Besson, D Coppage, D Davis, R Kotov, S Kravchenko, I Kwak, N Zhou, L Anderson, S Kubota, Y Lee, SJ Mahapatra, R O'Neill, JJ Poling, R Riehle, T Smith, A Alam, MS Athar, SB Ling, Z Mahmood, AH Timm, S Wappler, F Anastassov, A Duboscq, JE Gan, KK Gwon, C Hart, T Honscheid, K Kagan, H Kass, R Lee, J Lorenc, J Peterman, M Schwarthoff, H Wolf, A Zoeller, MM Richichi, SJ Severini, H Skubic, P Undrus, A Bishai, M Chen, S Fast, J Hinson, JW Menon, N Miller, DH Shibata, EI Shipsey, IPJ Glenn, S Kwon, Y Lyon, AL Roberts, S 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 Dambasuren, E Kopp, S Moneti, GC Mountain, R Schuh, S Skwarnicki, T Stone, S Titov, A Viehhauser, G Wang, JC Csorna, SE McLean, KW Marka, S Xu, Z AF 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 Miller, JS 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, HN Nelson, TK Roberts, D Behrens, BH Ford, WT Gritsan, A Krieg, H Roy, J Smith, JG Alexander, JP Baker, R Bebek, C Berger, BE Berkelman, K Boisvert, V Cassel, DG Crowcroft, DS Dickson, M von Dombrowski, S Drell, PS Ecklund, KM Ehrlich, R Foland, AD Gaidarev, P Galik, RS Gibbons, L Gittelman, B Gray, SW Hartill, DL Heltsley, BK Hopman, PI Kreinick, DL Lee, T Liu, Y Meyer, TO Mistry, NB Ng, CR Nordberg, E Ogg, M Patterson, JR Peterson, D Riley, D Soffer, A Thayer, JG Thies, PG Valant-Spaight, B Warburton, A Ward, C Athanas, M Avery, P Jones, CD Lohner, M Prescott, C Rubiera, AI Yelton, J Zheng, J Brandenburg, G Briere, RA 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 Selen, M Thaler, JJ Edwards, KW Bellerive, A Janicek, R Patel, PM Sadoff, AJ Ammar, R Baringer, P Bean, A Besson, D Coppage, D Davis, R Kotov, S Kravchenko, I Kwak, N Zhou, L Anderson, S Kubota, Y Lee, SJ Mahapatra, R O'Neill, JJ Poling, R Riehle, T Smith, A Alam, MS Athar, SB Ling, Z Mahmood, AH Timm, S Wappler, F Anastassov, A Duboscq, JE Gan, KK Gwon, C Hart, T Honscheid, K Kagan, H Kass, R Lee, J Lorenc, J Peterman, M Schwarthoff, H Wolf, A Zoeller, MM Richichi, SJ Severini, H Skubic, P Undrus, A Bishai, M Chen, S Fast, J Hinson, JW Menon, N Miller, DH Shibata, EI Shipsey, IPJ Glenn, S Kwon, Y Lyon, AL Roberts, S 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 Dambasuren, E Kopp, S Moneti, GC Mountain, R Schuh, S Skwarnicki, T Stone, S Titov, A Viehhauser, G Wang, JC Csorna, SE McLean, KW Marka, S Xu, Z CA CLEO Collaboration TI Search for baryon and lepton number violating decays of the tau lepton SO PHYSICAL REVIEW D LA English DT Article ID MONTE-CARLO; PHYSICS; LIBRARY AB We have searched for five decay modes of the tau lepton that simultaneously violate lepton and baryon number: tau(-) --> (p) over bar gamma, tau(-) --> (p) over bar pi(0), tau(-) --> (p) over bar eta, tau- --> (p) over bar 2 pi(0), and tau- --> (p) over bar pi(0)eta. The data used in the search were collected with the CLEO II detector at the Cornell Electron Storage Ring. The integrated luminosity of the data sample is 4.7 fb(-1), corresponding to the production of 4.3 x 10(6) tau(+)tau(-) events. No evidence is found for any of the decays, resulting in much improved upper limits on the branching fractions for the two-body decays and first upper limits for the three-body decays. [S0556-2821(99)50209-9]. C1 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. 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. Inst Particle Phys, Montreal, PQ, 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. Vanderbilt Univ, Nashville, TN 37235 USA. Univ Cincinnati, Cincinnati, OH 45221 USA. Univ Texas, Austin, TX 78712 USA. Yonsei Univ, Seoul 120749, South Korea. RP Virginia Polytech Inst & State Univ, Blacksburg, VA 24061 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; Poling, Ronald/0000-0001-7305-4702 NR 13 TC 10 Z9 10 U1 1 U2 2 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 MAY 1 PY 1999 VL 59 IS 9 AR 091303 DI 10.1103/PhysRevD.59.091303 PG 4 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 193BC UT WOS:000080114600003 ER PT J AU Grossman, Y Haber, HE AF Grossman, Y Haber, HE TI (S)neutrino properties in R-parity-violating supersymmetry: CP-conserving phenomena SO PHYSICAL REVIEW D LA English DT Article ID SOFTLY BROKEN SUPERSYMMETRY; LEPTON-NUMBER VIOLATION; BASIS-INDEPENDENT MEASURES; NEUTRINO MASSES; STANDARD MODEL; DARK-MATTER; FLAVOR VIOLATION; MAGNETIC-MOMENT; BREAKING; COLLIDERS AB R-parity-violating supersymmetry (with a conserved baryon number B) provides a framework for particle physics with lepton-number- (L-) violating interactions. We examine in detail the structure of the most general R-parity-violating (B-conserving) model of low-energy supersymmetry. We analyze the mixing of Higgs bosons with sleptons and the mixing of charginos and neutralinos with charged leptons and neutrinos, respectively. Implications for neutrino and sneutrino masses and mixing and CP-conserving sneutrino phenomena an considered L-violating low-energy supersymmetry can be probed at future colliders by studying the phenomenology of sneutrinos. Sneutrino-antisneutrino mass splittings and Lifetime differences can provide new opportunities to probe lepton number violation at colliders. [S0556-2821(99)04709-8]. C1 Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. Univ Calif Santa Cruz, Santa Cruz Inst Particle Phys, Santa Cruz, CA 95064 USA. Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. RP Grossman, Y (reprint author), Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. NR 63 TC 91 Z9 91 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 MAY 1 PY 1999 VL 59 IS 9 AR 093008 DI 10.1103/PhysRevD.59.093008 PG 15 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 193BC UT WOS:000080114600019 ER PT J AU Kiers, K Soni, A Wu, GH AF Kiers, K Soni, A Wu, GH TI CP violation in a two-Higgs doublet model for the top quark: B ->psi K-s SO PHYSICAL REVIEW D LA English DT Article ID CHANGING NEUTRAL CURRENTS; LEADING LOGARITHMS; MESON DECAY; B-DECAYS; WEAK; ASYMMETRIES; B->S-GAMMA; PHYSICS AB We explore charged-Higgs CP-violating effects in an intriguing two-Higgs doublet model which accords special status to the top quark. In this model the heaviness of the top quark originates naturally from the much larger VEV of the second Higgs doublet compared to that of the first. The phenomenology of this model is quite distinct from that of the usual formulations of the two-Higgs doublet model. In particular, the model can easily account for the observed CP violation in the kaon sector even if the CKM matrix is real. The associated non-standard CP phase can be monitored through measurements of the time-dependent CP asymmetry in B --> psi K-s in experiments at the upcoming B factories. [S0556-2821(99)01109-1]. C1 Taylor Univ, Dept Phys, Upland, IN 46989 USA. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Purdue Univ, Dept Phys, W Lafayette, IN 47907 USA. RP Kiers, K (reprint author), Taylor Univ, Dept Phys, 236 W Reade Ave, Upland, IN 46989 USA. EM kkiers@css.tayloru.edu; soni@bnl.gov; wu@physics.purdue.edu NR 26 TC 26 Z9 28 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 MAY 1 PY 1999 VL 59 IS 9 AR 096001 DI 10.1103/PhysRevD.59.096001 PG 5 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 193BC UT WOS:000080114600069 ER PT J AU Lee, W Weingarten, D AF Lee, W Weingarten, D TI Coupling constant and quark-loop expansion for corrections to the valence approximation SO PHYSICAL REVIEW D LA English DT Article ID SCALAR GLUEBALL; LATTICE QCD AB For full QCD vacuum expectation values we construct an expansion in quark-loop count and in powers of a coupling constant. The leading term in this expansion is the valence (quenched) approximation vacuum expectation value. Higher terms give corrections to the valence approximation. A test of the expansion is presented for moderately heavy quarks on a small lattice. We consider briefly an application of the expansion to quarkonium-glueball mixing. [S0556-2821(99)07209-4]. C1 IBM Res Corp, Yorktown Hts, NY 10598 USA. RP Los Alamos Natl Lab, Grp T8, POB 1663, Los Alamos, NM 87545 USA. 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 2470-0010 EI 2470-0029 J9 PHYS REV D JI Phys. Rev. D PD MAY 1 PY 1999 VL 59 IS 9 AR 094508 DI 10.1103/PhysRevD.59.094508 PG 7 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 193BC UT WOS:000080114600054 ER PT J AU Sasaki, S Miyamura, O AF Sasaki, S Miyamura, O TI Topological aspect of Abelian projected SU(2) lattice gauge theory SO PHYSICAL REVIEW D LA English DT Article ID CHIRAL-SYMMETRY BREAKING; GINZBURG-LANDAU THEORY; CONFINEMENT MECHANISM; QUARK CONFINEMENT; COLOR CONFINEMENT; QCD-MONOPOLES; INSTANTONS; DOMINANCE; EXISTENCE; VACUUM AB We show that the hypothesis of Abelian dominance allows QCD monopoles to preserve the topological feature of the QCD vacuum within SU(2) lattice gauge theory. An analytical study is made to find the relationship between the topological charge and QCD monopoles in the lattice formulation. The topological charge is explicitly represented in terms of the monopole current and the Abelian component of gauge fields in the Abelian dominated system. We numerically examine the relation and demonstrate the Abelian dominance in the topological structure by using Monte Carlo simulation. [S0556-2821(99)04209-5]. C1 Brookhaven Natl Lab, RIKEN, Res Ctr, Upton, NY 11973 USA. Hiroshima Univ, Dept Phys, Higashihiroshima 7398526, Japan. RP Brookhaven Natl Lab, RIKEN, Res Ctr, Upton, NY 11973 USA. EM ssasaki@bnl.gov NR 41 TC 19 Z9 19 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 MAY 1 PY 1999 VL 59 IS 9 AR 094507 DI 10.1103/PhysRevD.59.094507 PG 7 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 193BC UT WOS:000080114600053 ER PT J AU Giraud, BG Heumann, JM Lapedes, AS AF Giraud, BG Heumann, JM Lapedes, AS TI Superadditive correlation SO PHYSICAL REVIEW E LA English DT Article ID CONSTRUCTION AB The fact that correlation does not imply causation is well known. Correlation between variables at two sites does not imply that the two sites directly interact, because, e.g., correlation between distant sites may be induced by chaining of correlation between a set of intervening, directly interacting sites, Such "noncausal correlation" is well understood in statistical physics: an example is long-range order in spin systems, where spins which have only short-range direct interactions, e.g.: the Ising model, display correlation at a distance. It is less well recognized that such long-range "noncausal'' correlations can in fact be stronger than the magnitude of any causal correlation induced by direct interactions. We call this phenomenon superadditive correlation (SAC). We demonstrate this counterintuitive phenomenon by explicit examples in (i) a model spin system and (ii) a model continuous variable system, where both models are such that two variables have multiple intervening pathways of indirect interaction. We apply the technique known as decimation to explain SAC as an additive, constructive interference phenomenon between the multiple pathways of indirect interaction. We also explain the effect using a definition of the collective mode describing the intervening spin variables. Finally, we show that the SAC effect is mirrored in information theory, and is true for mutual information measures in addition to correlation measures. Generic complex systems typically exhibit multiple pathways of indirect interaction, making SAC a potentially widespread phenomenon. This affects, e.g., attempts to deduce interactions by examination of correlations, as well as, e.g., hierarchical approximation methods for multivariate probability distributions, which introduce parameters based on successive orders of correlation. [S1063-651X(99)07105-6]. C1 Ctr Etud Saclay, Serv Phys Theor, F-91191 Gif Sur Yvette, France. Hewlett Packard Co, Mfg Test Div, Loveland, CO 80539 USA. Santa Fe Inst, Los Alamos Natl Lab, Div Theoret, Santa Fe, NM 87501 USA. RP Giraud, BG (reprint author), Ctr Etud Saclay, Serv Phys Theor, F-91191 Gif Sur Yvette, France. NR 12 TC 14 Z9 15 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 MAY PY 1999 VL 59 IS 5 BP 4983 EP 4991 DI 10.1103/PhysRevE.59.4983 PN A PG 9 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 197TX UT WOS:000080382700041 PM 11969452 ER PT J AU Demo, P Kozisek, Z Sasik, R AF Demo, P Kozisek, Z Sasik, R TI Analytical approach to time lag in binary nucleation SO PHYSICAL REVIEW E LA English DT Article ID HOMOGENEOUS NUCLEATION; TRANSIENT NUCLEATION; KINETICS; GROWTH AB We present an analytical formula for the time required to establish steady state in a nucleating binary system. To test our solution, we evaluate the time lag for a range of activities of both components at the vapor-liquid transition, and show that our result is in much better agreement with a purely numerical simulation than other available analytical formulas, which overestimate the time lag by factors of from 2 to 200. [S1063-651X(99)10705-0]. C1 Acad Sci Czech Republ, Inst Phys, Prague 16253 6, Czech Republic. Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Demo, P (reprint author), Acad Sci Czech Republ, Inst Phys, Cukrovarnicka 10, Prague 16253 6, Czech Republic. RI Kozisek, Zdenek/F-7434-2014; Demo, Pavel/H-1432-2014 OI Kozisek, Zdenek/0000-0003-0823-5130; NR 16 TC 7 Z9 7 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 MAY PY 1999 VL 59 IS 5 BP 5124 EP 5127 DI 10.1103/PhysRevE.59.5124 PN A PG 4 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 197TX UT WOS:000080382700056 PM 11969467 ER PT J AU Kessler, DA Levine, H AF Kessler, DA Levine, H TI Steady-state cracks in viscoelastic lattice models SO PHYSICAL REVIEW E LA English DT Article ID DYNAMIC FRACTURE; PROPAGATION; INSTABILITY AB We study the steady-state motion of mode III cracks propagating on a lattice exhibiting viscoelastic dynamics. The introduction of a Kelvin viscosity eta allows for a direct comparison between lattice results and continuum treatments. Utilizing both numerical and analytical (Wiener-Hopf) techniques, we explore this comparison as a function of the driving displacement Delta and the number of transverse rows N. At any N, the continuum theory misses the lattice-trapping phenomenon; this is well known, but the introduction of eta introduces some new twists. More importantly, for large N even at large Delta, the standard two-dimensional elastodynamics approach completely misses the eta-dependent velocity selection, as this selection disappears completely in the leading order naive continuum limit of the lattice problem. [S1063-651X(99)13205-7]. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Dept Math, Berkeley, CA 94720 USA. Univ Calif San Diego, Dept Phys, La Jolla, CA 92093 USA. Bar Ilan Univ, Dept Phys, Ramat Gan, Israel. RP Kessler, DA (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Dept Math, 1 Cyclotron Rd, Berkeley, CA 94720 USA. RI Kessler, David/B-1391-2008; Levine, Herbert/C-1704-2008 OI Kessler, David/0000-0002-5279-1655; Levine, Herbert/0000-0002-8819-9055 NR 14 TC 24 Z9 24 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1063-651X J9 PHYS REV E JI Phys. Rev. E PD MAY PY 1999 VL 59 IS 5 BP 5154 EP 5164 DI 10.1103/PhysRevE.59.5154 PN A PG 11 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 197TX UT WOS:000080382700062 PM 11969473 ER PT J AU Elphick, C Hagberg, A Meron, E AF Elphick, C Hagberg, A Meron, E TI Multiphase patterns in periodically forced oscillatory systems SO PHYSICAL REVIEW E LA English DT Article AB Periodic forcing of an oscillatory system produces frequency locking bands within which the system frequency is rationally related to the forcing frequency. We study extended oscillatory systems that respond to uniform periodic forcing at one quarter of the forcing frequency (the 4:1 resonance). These systems possess four coexisting stable states, corresponding to uniform oscillations with successive phase shifts of pi/2. Using an amplitude equation approach near a Hopf bifurcation to uniform oscillations, we study front solutions connecting different phase states. These solutions divide into two groups: pi fronts separating states with a phase shift of pi and pi/2 fronts separating states with a phase shift of pi/2. We find a type of front instability when a stationary pi front "decomposes" into a pair of traveling pi/2 fronts as the forcing strength is decreased. The instability is degenerate for an amplitude equation with cubic nonlinearities. At the instability point a continuous family of pair solutions exists, consisting of pi/2 fronts separated by distances ranging from zero to infinity. Quintic nonlinearities lift the degeneracy at the instability point but do not change the basic nature of the instability. We conjecture the existence of similar instabilities in higher 2n:1 resonances (n = 3,4,...) where stationary pi fronts decompose into n traveling pi/n fronts. The instabilities designate transitions from stationary two-phase patterns to traveling 2n-phase patterns. As an example, we demonstrate with a numerical solution the collapse of a four-phase spiral wave into a stationary two-phase pattern as the forcing strength within the 4:1 resonance is increased. [S1063-651X(99)06705-7]. C1 Ctr Fis No Lineal & Sistemas Complejos Santiago, Santiago 17122, Chile. 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. Ben Gurion Univ Negev, Jacob Blaustein Inst Desert Res, IL-84990 Sede Boqer, Israel. Ben Gurion Univ Negev, Dept Phys, IL-84990 Sede Boqer, Israel. RP Elphick, C (reprint author), Ctr Fis No Lineal & Sistemas Complejos Santiago, Santiago 17122, Chile. RI MERON, EHUD/F-1810-2012 NR 14 TC 41 Z9 41 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1063-651X J9 PHYS REV E JI Phys. Rev. E PD MAY PY 1999 VL 59 IS 5 BP 5285 EP 5291 DI 10.1103/PhysRevE.59.5285 PN A PG 7 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 197TX UT WOS:000080382700077 PM 11969488 ER PT J AU Ulitsky, M Clark, T Turner, L AF Ulitsky, M Clark, T Turner, L TI Testing a random phase approximation for bounded turbulent flow SO PHYSICAL REVIEW E LA English DT Article AB Tractable implementation of a spectral closure requires that the modal representation of the energy satisfy a restricted random phase approximation (RRPA). This condition is exactly satisfied when the statistical system is homogeneous and the basis functions are Fourier modes. In this case, the ensemble average of the spectral covariance diagonalizes, i.e., < c(k(1))c(k(2))>= delta(k(1) + k(2))< c(k(1))c(k(2))>, where c(k,t) is a Fourier coefficient in a Galerkin representation of the velocity field. However, for inhomogeneous statistical systems in which the Fourier system is inappropriate, the RRPA requires validation. We use direct numerical simulations (DNSs) of the Navier-Stokes and truncated Euler equations to test the degree to which the RRPA is satisfied when applied to a recent representation due to Turner (LANL Unclassified Report No. LA-UR-96-3257) of a bounded turbulent rectangular channel flow with free slip, stress free walls. It is shown that a complete test of the RRPA for a fully inhomogeneous DNS with N-3 grid points actually requires N-3+1 members in the ensemble. The "randomness" of the phase can be characterized by a probability density function (PDF) of the modulus of the normalized spectral covariance. Results reveal that for both the Navier-Stokes and Euler systems the PDF does not change in time as the turbulence decays, and that the PDF for the Euler system is virtually identical to the one produced from an ensemble of random fields. This result is consistent with the equipartition of energy for the Euler system, in which the RRPA becomes an exact result rather than an approximation as the number of realizations approaches N-3 + 1. The slight differences observed between the PDF produced from the random fields and the one from the Navier-Stokes system are thus shown to be entirely a result of the presence of a finite viscosity. It is also shown that there is great variation between statistics computed over the ensemble and those for a single realization. [S1063-651X(99)11605-2]. C1 Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Ulitsky, M (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, Mail Stop B216, Los Alamos, NM 87545 USA. NR 17 TC 7 Z9 7 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1063-651X J9 PHYS REV E JI Phys. Rev. E PD MAY PY 1999 VL 59 IS 5 BP 5511 EP 5522 DI 10.1103/PhysRevE.59.5511 PN B PG 12 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 197TZ UT WOS:000080382900012 PM 11969530 ER PT J AU Martin, JE Hill, KM Tigges, CP AF Martin, JE Hill, KM Tigges, CP TI Magnetic-field-induced optical transmittance in colloidal suspensions SO PHYSICAL REVIEW E LA English DT Article ID ELECTRORHEOLOGICAL FLUIDS; SIMULATION AB Through simulation and experiment we demonstrate that when a magnetic field is applied to a suspension of magnetic particles, the optical attenuation length along the direction of the field increases dramatically, due to the formation of chainlike structures that allow the transmission of light between the strongly absorbing particles. This phenomenon is interesting for two reasons; first, there might be practical applications for this effect, such as optical-fiber-based magnetic field sensors, and second, measuring the time evolution of the optical attenuation length enables us to determine the kinetics of structure formation, which can be compared to the predictions of simulation and theory. In agreement with both simulation and theory, the optical attenuation length increases as a power of time, but much less light is actually transmitted than expected, especially at higher particle concentrations. We conclude that particle roughness, which is not included in either theory or simulation, plays a significant role in structural development, by pinning structures into local minima. [S1063-651X(99)05405-7]. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Martin, JE (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 21 TC 76 Z9 77 U1 1 U2 5 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 MAY PY 1999 VL 59 IS 5 BP 5676 EP 5692 DI 10.1103/PhysRevE.59.5676 PN B PG 17 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 197TZ UT WOS:000080382900033 PM 11969551 ER PT J AU Jiang, Y Swart, PJ Saxena, A Asipauskas, M Glazier, JA AF Jiang, Y Swart, PJ Saxena, A Asipauskas, M Glazier, JA TI Hysteresis and avalanches in two-dimensional foam rheology simulations SO PHYSICAL REVIEW E LA English DT Article ID HIGHLY CONCENTRATED EMULSIONS; 2-DIMENSIONAL SOAP FROTH; Q POTTS-MODEL; BUBBLE-SCALE; GRAIN-GROWTH; AQUEOUS FOAM; 1/F NOISE; DYNAMICS; STRAIN; MECHANICS AB Foams have unique rheological properties that range from solidlike to fluidlike. We study two-dimensional noncoarsening foams of different disorder under shear in a Monte Carlo simulation, using a driven large-e Potts model. Simulations of periodic shear on an ordered foam show several different response regimes. At small strain amplitudes, bubbles deform and recover their shapes elastically, and the macroscopic response is that of a linear elastic cellular material. For increasing strain amplitude, the energy-strain curve starts to exhibit hysteresis before any topological rearrangements occur, indicating a macroscopic viscoelastic response. When the applied strain amplitude exceeds a critical value, the yield strain, topological rearrangements occur, the foam starts to flow, and we observe macroscopic irreversibility. We find that the dynamics of topological rearrangements depend sensitively on the structural disorder. Structural disorder decreases the yield strain; sufficiently high disorder changes the macroscopic response of a foam from a viscoelastic solid to a viscoelastic fluid. This wide-ranging dynamical response and the associated history effects of foams result from avalanchelike rearrangement events. The spatiotemporal statistics of rearrangement events do not display long-range correlations for ordered foams or at low shear rates, consistent with experimental observations. As the shear rate or structural disorder increases, the topological events become more correlated and their power spectra change from that of white noise toward 1/f noise. Intriguingly, the power spectra of the total stored energy also exhibit this 1/f trend. [S1063-651X(99)11405-3]. C1 Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Univ Notre Dame, Dept Phys, Notre Dame, IN 46556 USA. RP Jiang, Y (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, CNLS, MS B258, Los Alamos, NM 87544 USA. NR 43 TC 63 Z9 64 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 MAY PY 1999 VL 59 IS 5 BP 5819 EP 5832 DI 10.1103/PhysRevE.59.5819 PN B PG 14 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 197TZ UT WOS:000080382900044 PM 11969562 ER PT J AU Schroeder, CB Lee, PB Wurtele, JS Esarey, E Leemans, WP AF Schroeder, CB Lee, PB Wurtele, JS Esarey, E Leemans, WP TI Generation of ultrashort electron bunches by colliding laser pulses SO PHYSICAL REVIEW E LA English DT Article ID PLASMA-WAVES; ACCELERATION; WAKEFIELD; INJECTION AB A proposed laser-plasma-based relativistic electron source [E. Esarey et al., Phys. Rev. Lett. 79, 2682 (1997)] using laser-triggered injection of electrons is investigated. The source generates ultrashort electron bunches by dephasing and trapping background plasma electrons undergoing fluid oscillations in an excited plasma wake; The plasma electrons are dephased by colliding two counterpropagating laser pulses which generate a slow phase velocity beat wave. Laser pulse intensity thresholds for trapping and the optimal wake phase for injection are calculated. Numerical simulations of rest particles, with prescribed plasma and laser fields, are used to verify analytic predictions and to study the longitudinal and transverse dynamics of the trapped plasma electrons. Simulations indicate that the colliding laser pulse injection scheme has the capability to produce relativistic femtosecond electron bunches with fractional energy spread of order a few percent and normalized transverse emittance less than 1 mm mrad using 1 TW injection laser pulses. [S1063-651X(99)04505-5]. C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Ernest Orlando Lawrence Berkeley Natl Lab, Ctr Beam Phys, Berkeley, CA 94720 USA. RP Schroeder, CB (reprint author), Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. RI wurtele, Jonathan/J-6278-2016; OI wurtele, Jonathan/0000-0001-8401-0297; Schroeder, Carl/0000-0002-9610-0166 NR 23 TC 70 Z9 71 U1 0 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 MAY PY 1999 VL 59 IS 5 BP 6037 EP 6047 DI 10.1103/PhysRevE.59.6037 PN B PG 11 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 197TZ UT WOS:000080382900070 PM 11969588 ER PT J AU Li, X AF Li, X TI Relativistic pondermotive Hamiltonian for electrons in an intense laser field SO PHYSICAL REVIEW E LA English DT Article ID PONDEROMOTIVE FORCE; VACUUM; ACCELERATION; PULSES AB A Hamiltonian theory of the electron drift motion in an intense laser pulse is presented. The action-variational Lie perturbation method is utilized to derive the relativistic pondermotive Hamiltonian in a rigorous and systematic way. The results include: the electron drift motion in a linearly polarized pulse is slightly anisotropic because of the finite pulse duration effects, and its drift in a circularly polarized pulse contains a vortex component. [S1063-651X(99)11805-1]. C1 Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Li, X (reprint author), Princeton Univ, Princeton Plasma Phys Lab, POB 400, Princeton, NJ 08543 USA. NR 15 TC 2 Z9 2 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 MAY PY 1999 VL 59 IS 5 BP 6048 EP 6052 DI 10.1103/PhysRevE.59.6048 PN B PG 5 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 197TZ UT WOS:000080382900071 PM 11969589 ER PT J AU Failor, BH Fernandez, JC Wilde, BH Osterheld, AL Cobble, JA Gobby, PL AF Failor, BH Fernandez, JC Wilde, BH Osterheld, AL Cobble, JA Gobby, PL TI Hot, dense, millimeter-scale, high-Z plasmas for laser-plasma interactions studies SO PHYSICAL REVIEW E LA English DT Article ID HOHLRAUM PLASMAS; T-E; DEPENDENCE; SCATTERING AB We have designed and produced hot, millimeter;scale, high-Z plasmas of interest for National Ignition Facility hohlraum target design. Using a high-Z gas fill produces electron temperatures in the 3.5-6-keV range, the highest temperatures measured to date for high-density (10(21) e/cm(3)) laser-heated plasmas, and much higher than the 3 keV found for low-Z (neopentane) fills. These measurements are in good agreement with the target design calculations, and the L-shell spectroscopic approach used to estimate the electron temperature has certain advantages over traditional K-shell approaches. [S1063-651X(99)15205-X]. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Maxwell Phys Int, San Leandro, CA 94577 USA. RP Failor, BH (reprint author), Univ Calif Los Alamos Natl Lab, POB 1660, Los Alamos, NM 87545 USA. RI Fernandez, Juan/H-3268-2011 OI Fernandez, Juan/0000-0002-1438-1815 NR 16 TC 5 Z9 5 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 MAY PY 1999 VL 59 IS 5 BP 6053 EP 6057 DI 10.1103/PhysRevE.59.6053 PN B PG 5 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 197TZ UT WOS:000080382900072 PM 11969590 ER PT J AU Urbanus, WH Bongers, WA van der Geer, CAJ Manintveld, P Plomp, J Pluygers, J Poelman, AJ Smeets, PHM Verhoeven, AGA Bratman, VL Denisov, GG Savilov, AV Shmelyov, MY Caplan, N Varfolomeev, AA Tolmachev, SV Ivanchenkov, SN AF Urbanus, WH Bongers, WA van der Geer, CAJ Manintveld, P Plomp, J Pluygers, J Poelman, AJ Smeets, PHM Verhoeven, AGA Bratman, VL Denisov, GG Savilov, AV Shmelyov, MY Caplan, N Varfolomeev, AA Tolmachev, SV Ivanchenkov, SN TI High-power electrostatic free-electron maser as a future source for fusion plasma heating: Experiments in the short-pulse regime SO PHYSICAL REVIEW E LA English DT Article ID BEAM TRANSPORT; LASER; FEM; COMPETITION; SIMULATIONS; TRANSVERSE; DYNAMICS; BUILDUP AB A high-power,frequency-tunable electrostatic free-electron maser, being developed at the FOM Institute for Plasma Physics "Rijnhuizen," shows lasing at various frequencies. An output power of 730 kW at 206 GHz is generated by a 7.2-A, 1.77-MeV electron beam, and 380 kW at 165 GHz is generated by a 7.4-A, 1.65-MeV electron beam. In the present experimental setup, without recovery of the spent electron beam power, the pulse length is limited to 12 mu s. Nevertheless, the main issues, such as the possibility of high-power, single-mode operation and frequency tuning, have been confirmed. The experimental results and the dynamics of the laser process are well in accordance with simulations. [S1063-651X(99)03905-7]. C1 EURATOM, FOM, Inst Plasmafys Rijnhuizen, NL-3430 BE Nieuwegein, Netherlands. Russian Acad Sci, Inst Appl Phys, Nizhnii Novgorod 603600, Russia. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. IV Kurchatov Atom Energy Inst, Russian Res Ctr, Moscow 123182, Russia. RP Urbanus, WH (reprint author), EURATOM, FOM, Inst Plasmafys Rijnhuizen, Postbus 1207, NL-3430 BE Nieuwegein, Netherlands. NR 19 TC 14 Z9 15 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 MAY PY 1999 VL 59 IS 5 BP 6058 EP 6063 DI 10.1103/PhysRevE.59.6058 PN B PG 6 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 197TZ UT WOS:000080382900073 PM 11969591 ER PT J AU Flach, S Zolotaryuk, Y Kladko, K AF Flach, S Zolotaryuk, Y Kladko, K TI Moving lattice kinks and pulses: An inverse method SO PHYSICAL REVIEW E LA English DT Article ID SINE-GORDON SYSTEM; NONLINEAR LATTICES; LOCALIZED MODES; SOLITARY WAVES; DISCRETE; BREATHERS; EXISTENCE; MOBILITY; DYNAMICS; SOLITONS AB We develop a general mapping from given kink or pulse shaped traveling-wave solutions including their velocity to the equations of motion on one-dimensional lattices which support these solutions. We apply this mapping-by definition an inverse method-to acoustic solitons in chains with nonlinear intersite interactions, nonlinear Klein-Gordon chains, reaction-diffusion equations, and discrete nonlinear Schrodinger systems. Potential functions can be found in a unique way provided the pulse shape is reflection symmetric and pulse and kink shapes are at least C-2 functions. For kinks we discuss the relation of our results to the problem of a Peierls-Nabarro potential and continuous symmetries. We then generalize our method to higher dimensional lattices for reaction-diffusion systems. We find that increasing also the number of components easily allows for moving solutions. [S1063-651X(99)14305-8]. C1 Max Planck Inst Phys Komplexer Syst, D-01187 Dresden, Germany. Univ Calif Los Alamos Natl Lab, Ctr Nonlinear Studies, Div Theoret, Los Alamos, NM 87545 USA. Univ Calif Los Alamos Natl Lab, Condensed Matter Phys Grp, Los Alamos, NM 87545 USA. RP Flach, S (reprint author), Max Planck Inst Phys Komplexer Syst, Nothnitzer Str 38, D-01187 Dresden, Germany. RI Zolotaryuk, Yaroslav/A-4675-2010; Flach, Sergej/J-7047-2013 NR 22 TC 65 Z9 67 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1063-651X J9 PHYS REV E JI Phys. Rev. E PD MAY PY 1999 VL 59 IS 5 BP 6105 EP 6115 DI 10.1103/PhysRevE.59.6105 PN B PG 11 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 197TZ UT WOS:000080382900078 PM 11969596 ER PT J AU Braiman, Y Hentschel, HGE Family, F Mak, C Krim, J AF Braiman, Y Hentschel, HGE Family, F Mak, C Krim, J TI Tuning friction with noise and disorder SO PHYSICAL REVIEW E LA English DT Article ID STICK-SLIP MOTION; QUARTZ-CRYSTAL MICROBALANCE; ATOMIC-SCALE FRICTION; INTERFACIAL FRICTION; NONLINEAR DYNAMICS; SLIDING FRICTION; DRY FRICTION; DEFECTS; FILM; LUBRICATION AB We present numerical and experimental evidence which demonstrates that under certain conditions friction can be reduced by spatial disorder and/or thermal noise. We discuss possible mechanisms for this behavior. [S1063-651X(99)51405-0]. C1 Oak Ridge Natl Lab, Ctr Engn Sci Adv Res, Comp Sci & Math Div, Oak Ridge, TN 37831 USA. Emory Univ, Dept Phys, Atlanta, GA 30322 USA. Northeastern Univ, Dept Phys, Boston, MA 02115 USA. N Carolina State Univ, Dept Phys, Raleigh, NC 27695 USA. RP Braiman, Y (reprint author), Oak Ridge Natl Lab, Ctr Engn Sci Adv Res, Comp Sci & Math Div, Oak Ridge, TN 37831 USA. NR 46 TC 29 Z9 29 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1063-651X J9 PHYS REV E JI Phys. Rev. E PD MAY PY 1999 VL 59 IS 5 BP R4737 EP R4740 DI 10.1103/PhysRevE.59.R4737 PN A PG 4 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA 197TX UT WOS:000080382700008 PM 11969507 ER PT J AU Mourant, JR Johnson, TM Los, G Bigio, LJ AF Mourant, JR Johnson, TM Los, G Bigio, LJ TI Non-invasive measurement of chemotherapy drug concentrations in tissue: preliminary demonstrations of in vivo measurements SO PHYSICS IN MEDICINE AND BIOLOGY LA English DT Article ID SOURCE-DETECTOR SEPARATIONS; STATE DIFFUSE-REFLECTANCE; PHOTODYNAMIC THERAPY; OPTICAL-PROPERTIES; IN-VIVO; MICRODIALYSIS PROBE; LIGHT DOSIMETRY; SPECTROSCOPY; SCATTERING; MODEL AB Measurements of the tissue concentrations of two chemotherapy agents have been made in vivo on an animal tumour model. The method used is based on elastic-scattering spectroscopy (ESS) and utilizes a fibre-optic probe spectroscopic system. A broadband light source is used to acquire data over a broad range of wavelengths and, therefore, to facilitate the separation of absorptions from various chromophores. The results of the work include measurements of the time course of the drug concentrations as well as a comparison of the optical measurements with high-performance liquid chromatography (HPLC) analysis of the drug concentrations at the time of sacrifice. It is found that the optical measurements correlate linearly with HPLC measurements, but give lower absolute values. C1 Univ Calif Los Alamos Natl Lab, Biosci & Biotechnol Grp, Los Alamos, NM 87545 USA. UCSD, Ctr Canc, La Jolla, CA 92117 USA. RP Mourant, JR (reprint author), Univ Calif Los Alamos Natl Lab, Biosci & Biotechnol Grp, MS-E535, Los Alamos, NM 87545 USA. OI Bigio, Irving/0000-0003-4168-1466 NR 53 TC 90 Z9 90 U1 0 U2 5 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 MAY PY 1999 VL 44 IS 5 BP 1397 EP 1417 DI 10.1088/0031-9155/44/5/322 PG 21 WC Engineering, Biomedical; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Radiology, Nuclear Medicine & Medical Imaging GA 199EH UT WOS:000080467100022 PM 10368027 ER PT J AU Shestakov, AI AF Shestakov, AI TI Time-dependent simulations of point explosions with heat conduction SO PHYSICS OF FLUIDS LA English DT Article AB A hydrodynamic-diffusion code is used to simulate a point explosion. The gas motion is governed by both hydrodynamics and nonlinear heat conduction and is a combination of the well-known, self-similar Taylor-Sedov spherically expanding shock wave and the spherically expanding thermal wave. Two problems are discussed, rn the first problem, a similarity solution exists if the diffusion coefficient is given in terms of powers of density and temperature which also define the ambient spatial density profile. If the initial explosion energy is small, the diffusive effect is limited to a region behind the shock. However, if the explosion energy is large, the thermal front precedes the hydrodynamic front, which is then an isothermal shock. In the second problem, the initial density is constant and the diffusion coefficient depends on only a power of the temperature. In this case, the solution is not self-similar; in early times, heat conduction dominates; in late times-hydrodynamics. The problems were previously analyzed by Reinicke and Meyer-ter-Vehn in terms of similarity variables. (C) 1999 American Institute of Physics. [S1070-6631(99)02005-X]. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Shestakov, AI (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 6 TC 16 Z9 16 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-6631 J9 PHYS FLUIDS JI Phys. Fluids PD MAY PY 1999 VL 11 IS 5 BP 1091 EP 1095 DI 10.1063/1.869979 PG 5 WC Mechanics; Physics, Fluids & Plasmas SC Mechanics; Physics GA 187BY UT WOS:000079767300015 ER PT J AU He, XY Zhang, RY Chen, SY Doolen, GD AF He, XY Zhang, RY Chen, SY Doolen, GD TI On the three-dimensional Rayleigh-Taylor instability SO PHYSICS OF FLUIDS LA English DT Article ID LATTICE BOLTZMANN MODEL; PARALLEL COMPUTATION; NUMERICAL-SIMULATION; FRONT TRACKING; FLUIDS; FLOWS; EQUATION AB The three-dimensional Rayleigh-Taylor instability is studied using a lattice Boltzmann scheme for multiphase flow in the nearly incompressible limit. This study focuses on the evolution of the three-dimensional structure of the interface. In addition to the bubble and spike fronts, a saddle point is found to be another important landmark on the interface. Two layers of heavy-fluid roll-ups, one at the spike tip and the other at the saddle point, were observed. The secondary instability in the horizontal planes entangles the already complicated structure of the interface. Parallel computations are utilized to accommodate the massive computational requirements of the simulations. (C) 1999 American Institute of Physics. [S1070-6631(99)00605-4]. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP He, XY (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. RI Chen, Shiyi/A-3234-2010 NR 34 TC 105 Z9 110 U1 1 U2 18 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-6631 J9 PHYS FLUIDS JI Phys. Fluids PD MAY PY 1999 VL 11 IS 5 BP 1143 EP 1152 DI 10.1063/1.869984 PG 10 WC Mechanics; Physics, Fluids & Plasmas SC Mechanics; Physics GA 187BY UT WOS:000079767300020 ER PT J AU Roberts, CD AF Roberts, CD TI Nonperturbative effects in QCD at finite temperature and density SO PHYSICS OF PARTICLES AND NUCLEI LA English DT Review ID PION FORM-FACTOR; DYSON-SCHWINGER-EQUATIONS; CHIRAL-SYMMETRY BREAKING; MUON-PROTON-SCATTERING; HOT GAUGE-THEORIES; RHO-MESON; VECTOR-MESONS; SUM-RULES; QUARK PROPAGATOR; GLUON PROPAGATOR AB These lecture notes illustrate the application of Dyson-Schwinger equations in QCD. The extensive body of work at zero temperature and chemical potential is represented by a selection of contemporary studies that focus on solving the Bethe-Salpeter equation, deriving an exact mass formula in QCD that describes light and heavy pseudoscalar mesons simultaneously, and the calculation of the electromagnetic pion form factor and the vector-meson electroproduction cross sections. These applications emphasize the qualitative importance of the momentum-dependent dressing of elementary Schwinger functions in QCD, which provides a unifying connection between disparate phenomena. They provide a solid foundation for an extension of the approach to nonzero temperature and chemical potential. The essential, formal elements of this application are described, and four contemporary studies are employed to exemplify the method and its efficacy. They study the demarcation of the phase boundary for deconfinement and chiral symmetry restoration, the calculation of bulk thermodynamic properties of the quark-gluon plasma, and the response of pi- and rho- meson observables to T and mu. Along the way a continuum order parameter for deconfinement is introduced, an anticorrelation between the response of masses and decay constants to T and their response to mis elucidated, and a (T, mu) mirroring of the slow approach of bulk thermodynamic quantities to their ultrarelativistic limit is highlighted. These effects too are tied to the momentum-dependent dressing of the elementary Schwinger functions. (C) 1999 American Institute of Physics. [S1063-7796(99)00103-5]. C1 Argonne Natl Lab, Phys Div 203, Argonne, IL 60439 USA. RP Roberts, CD (reprint author), Argonne Natl Lab, Phys Div 203, 9700 S Cass Ave, Argonne, IL 60439 USA. OI Roberts, Craig/0000-0002-2937-1361 NR 103 TC 21 Z9 21 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1063-7796 J9 PHYS PART NUCLEI JI Phys. Part. Nuclei PD MAY-JUN PY 1999 VL 30 IS 3 BP 223 EP 257 DI 10.1134/1.953105 PG 35 WC Physics, Particles & Fields SC Physics GA 209UT UT WOS:000081067800001 ER PT J AU Hwang, DQ Ryutova, M McLean, H AF Hwang, DQ Ryutova, M McLean, H TI Penetration of a compressible magnetized plasma object into a low beta target plasma SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 40th Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 16-20, 1998 CL NEW ORLEANS, LOUISIANA SP Amer Phys Soc, Div Plasma Phys ID COMPACT AB The effects of the shape and compressibility of a perfectly conducting spheromaklike compact toroid (SCT) propagating into a low beta plasma have been studied. Simple tools that allow one to identify conditions for the optimum penetration of the SCT into the low beta target plasma have been developed. The main results obtained are (1) squeezed (prolate) SCT's penetrate more easily; (2) including SCT compressibility reduces injection power requirement, and (3) there exists a broad parameter range where the SCT injection can maintain tokamak particle inventory while simultaneously reducing external auxiliary heating requirements. (C) 1999 American Institute of Physics. [S1070-664X(99)03105-5]. C1 Univ Calif Davis, Lawrence Livermore Natl Lab, Dept Appl Sci, Livermore, CA 94550 USA. RP Hwang, DQ (reprint author), Univ Calif Davis, Lawrence Livermore Natl Lab, Dept Appl Sci, Livermore, CA 94550 USA. NR 8 TC 11 Z9 11 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1999 VL 6 IS 5 BP 1515 EP 1521 DI 10.1063/1.873404 PN 1 PG 7 WC Physics, Fluids & Plasmas SC Physics GA 190MZ UT WOS:000079969100020 ER PT J AU Qin, H Tang, WM Lee, WW Rewoldt, G AF Qin, H Tang, WM Lee, WW Rewoldt, G TI Gyrokinetic perpendicular dynamics SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 40th Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 16-20, 1998 CL NEW ORLEANS, LOUISIANA SP Amer Phys Soc, Div Plasma Phys ID GUIDING CENTER MOTION; PARTICLE SIMULATION; HAMILTONIAN-FORMULATION; FREQUENCY GYROKINETICS; EQUATIONS; PLASMAS; PHASE; INSTABILITIES; TRANSPORT; TOKAMAKS AB Gyrokinetic perpendicular dynamics, an important component not systematically considered in previous gyrokinetic theories, is identified and developed. A "distribution function'' S and its governing gyrokinetic equation are introduced to describe the gyrokinetic perpendicular dynamics. The complete treatment of the perpendicular current rendered by the gyrokinetic perpendicular dynamics enables one to recover the compressional Alfven wave from the gyrokinetic model. From the viewpoint of gyrokinetic theory, the physics of the compressional Alfven wave is the polarization current at second order. Therefore, in a low frequency gyrokinetic system, the compressional Alfven wave is naturally decoupled from the shear Alfven wave and drift wave. In the gyrocenter coordinates, the gyrophase dependent parts of the distribution function S and (f) over tilde are decoupled from the gyrophase independent part f. Introducing the gyrokinetic perpendicular dynamics also extends the gyrokinetic model to arbitrary frequency modes. As an example, the Bernstein wave is recovered from the gyrokinetic model. The gyrokinetic perpendicular dynamics uncovered here emphasizes that the spirit of gyrokinetic reduction is to decouple the gyromotion from the particle's gyrocenter orbit motion, instead of averaging out the gyromotion. (C) 1999 American Institute of Physics. [S1070-664X(99)02705-6]. 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 50 TC 28 Z9 28 U1 1 U2 4 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1999 VL 6 IS 5 BP 1575 EP 1588 DI 10.1063/1.873411 PN 1 PG 14 WC Physics, Fluids & Plasmas SC Physics GA 190MZ UT WOS:000079969100027 ER PT J AU Pletzer, A Perkins, FW AF Pletzer, A Perkins, FW TI Stabilization of neoclassical tearing modes using a continuous localized current drive SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 40th Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 16-20, 1998 CL NEW ORLEANS, LOUISIANA SP Amer Phys Soc, Div Plasma Phys ID REGION MATCHING DATA; MAGNETIC ISLANDS; NONLINEAR DYNAMICS; TOKAMAK PLASMAS; STABILITY; THRESHOLD; PRESSURE AB The stability of a test equilibrium relevant to the International Thermonuclear Experimental Reactor [Fusion Eng. Des. 36, 9 (1997)] has been studied within the framework of the neoclassical island theory. The most unstable modes, with the most positive matching index Delta', have been found by solving the toroidal stability equation to have 3/2, 2/1, and 4/3 helicities. Quasilinear effects resulting from the flattening of the current profile as the island develops are important and stabilizing. Large saturated islands are predicted to arise from a combination of strong bootstrap current drive and weakly negative Delta'. The island size can be significantly reduced by applying a continuous current drive at the unstable rational surfaces. The so-obtained reduction of island width is approximately proportional to the current drive and inversely proportional to the square of the current channel. This stabilization relies on the removal of the free energy in the outer region and can thus be regarded as a Delta' effect. (C) 1999 American Institute of Physics. [S1070-664X(99)03505-3]. C1 PPB Ecublens, Assoc Euratom Confederat Suisse, Ctr Rech Phys Plasmas, CH-1015 Lausanne, Switzerland. JCT, ITER, La Jolla, CA 92037 USA. RP Pletzer, A (reprint author), Princeton Univ, Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 35 TC 54 Z9 54 U1 0 U2 14 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1999 VL 6 IS 5 BP 1589 EP 1600 DI 10.1063/1.873412 PN 1 PG 12 WC Physics, Fluids & Plasmas SC Physics GA 190MZ UT WOS:000079969100028 ER PT J AU Wang, ZH Cohen, SA AF Wang, ZH Cohen, SA TI Geometrical aspects of a hollow-cathode planar magnetron SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 40th Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 16-20, 1998 CL NEW ORLEANS, LOUISIANA SP Amer Phys Soc, Div Plasma Phys ID DISCHARGE; DEPOSITION AB A hollow-cathode planar magnetron (HCPM), built by surrounding a planar sputtering-magnetron cathode with a hollow-cathode structure (HCS) [Z. Wang and S. A. Cohen, J. Vac. Sci. Technol. A 17, 77 (1999)], is operable at substantially lower pressures than its planar-magnetron counterpart. HCPM operational parameters depend on the inner diameter D and length L of its cylindrical HCS. Only when L is greater than L-0, a critical length, is the HCPM operable in the new low-pressure regime. The critical length varies with HCS inner diameter D. Explanations of the lower operational pressure regime, critical length, and plasma shape are proposed and compared with a one-dimension diffusion model for energetic electron transport. At pressures above 1 mTorr, Bohm diffusion (temperature congruent to primary electron energy), with an ambipolar constraint, can explain the ion-electron pair creation required to sustain the discharge. At the lowest pressure, similar to 0.3 mTorr, collision-limited diffusion creates fewer ion-electron pairs than required for steady state and therefore cannot explain the experimental data. The critical length L-0 is consistent with the magnetization length of the primary electrons. (C) 1999 American Institute of Physics. [S1070-664X(99)04305-0]. C1 Princeton Univ, Plasma Phys Lab, Princeton, NJ 08543 USA. RP Wang, ZH (reprint author), Univ Calif Los Alamos Natl Lab, MS E 526, Los Alamos, NM 87545 USA. NR 22 TC 15 Z9 16 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1999 VL 6 IS 5 BP 1655 EP 1666 DI 10.1063/1.873421 PN 1 PG 12 WC Physics, Fluids & Plasmas SC Physics GA 190MZ UT WOS:000079969100038 ER PT J AU Rosen, MD AF Rosen, MD TI The physics issues that determine inertial confinement fusion target gain and driver requirements: A tutorial SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 40th Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 16-20, 1998 CL NEW ORLEANS, LOUISIANA SP Amer Phys Soc, Div Plasma Phys ID NOVA LASER; IGNITION AB This paper presents a simplified, tutorial approach to determining the gains of inertial confinement fusion (ICF) targets, via a basic, zero-dimensional ("0-D''), energy "bookkeeping'' of input (parametrized by ICF drivers' coupling efficiencies to the target, and subsequent hydrodynamic efficiencies of implosion) versus output (thermonuclear burn efficiency and target fuel mass). Physics issues/constraints such as hydrodynamic instabilities, symmetry and implosion velocity requirements will be discussed for both the direct drive (driver impinging directly on the target) and indirect drive (x-ray implosion within a driver heated hohlraum) approaches to ICF. Supplementing the 0-D model with simple models for hohlraum wall energy loss (to predict coupling efficiencies! and a simple one-dimensional (1-D) model of the implosion as a spherical rocket (to predict hydrodynamic implosion efficiencies) allows gains to be predicted that compare well with the results of complex two-dimensional (2-D) radiation hydrodynamic simulations. (C) 1999 American Institute of Physics. [S1070-664X(99)92205-X]. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Rosen, MD (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 13 TC 56 Z9 60 U1 2 U2 8 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1999 VL 6 IS 5 BP 1690 EP 1699 DI 10.1063/1.873427 PN 2 PG 10 WC Physics, Fluids & Plasmas SC Physics GA 190ND UT WOS:000079969500003 ER PT J AU Cohen, BI Hooper, EB Kaiser, TB Williams, EA Domier, CW AF Cohen, BI Hooper, EB Kaiser, TB Williams, EA Domier, CW TI Modeling of ultra-short-pulse reflectometry SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 40th Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 16-20, 1998 CL NEW ORLEANS, LOUISIANA SP Amer Phys Soc, Div Plasma Phys ID DENSITY PROFILE MEASUREMENTS; MICROWAVE REFLECTOMETRY; ELECTROMAGNETIC-WAVES; MAGNETIC FLUCTUATIONS; PLASMA; SIMULATIONS; FIELD; SENSITIVITY; SCATTERING; CONVERSION AB Pulsed reflectometry using both ordinary (O) and extraordinary (X) modes can provide time- and space-resolved measurements of the electron density, the magnitude of the magnetic field, the magnetic shear as a function of radius, and information on density and magnetic fluctuations. Such a diagnostic also yields the current profile from the curl of the magnetic field. This research addresses theoretical issues associated with the use of pulsed reflectometry with particular emphasis on applications in the Sustained Spheromak Physics Experiment (SSPX) at the Lawrence Livermore National Laboratory [E. B. Hooper et al., "Sustained Spheromak Physics Experiment,'' in Proceedings of the 17th International Atomic Energy Agency (IAEA) Fusion Energy Conference, Yokohama, Japan, October 19-24, 1998, Lawrence Livermore National Laboratory Report UCRL-JC-132034 (September 29, 1998)]. Simulation results are presented for O- and X-mode mixed-polarization reflectometry and linear mode conversion in two spatial dimensions. The profile reconstruction algorithms depend on Wentzel-Kramers-Brillouin-Jeffreys (WKBJ) formulae for group delays and linear mode conversion, which agree reasonably well with direct numerical solutions of the wave equation. Reconstructions of the electron density and modulus of the magnetic field are relatively robust in the presence of two-dimensional electron density and magnetic perturbations of the plasma. (C) 1999 American Institute of Physics. [S1070-664X(99)90205-7]. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Univ Calif Davis, Dept Appl Sci, Davis, CA 95616 USA. RP Cohen, BI (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 39 TC 8 Z9 8 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1999 VL 6 IS 5 BP 1732 EP 1741 DI 10.1063/1.873487 PN 2 PG 10 WC Physics, Fluids & Plasmas SC Physics GA 190ND UT WOS:000079969500008 ER PT J AU Ji, HT Yamada, M Hsu, S Kulsrud, R Carter, T Zaharia, S AF Ji, HT Yamada, M Hsu, S Kulsrud, R Carter, T Zaharia, S TI Magnetic reconnection with Sweet-Parker characteristics in two-dimensional laboratory plasmas SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 40th Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 16-20, 1998 CL NEW ORLEANS, LOUISIANA SP Amer Phys Soc, Div Plasma Phys ID MODELS AB Magnetic reconnection has been studied experimentally in a well-controlled, two-dimensional laboratory magnetohydrodynamic plasma. The observations are found to be both qualitatively and quantitatively consistent with a generalized Sweet-Parker model which incorporates compressibility, downstream pressure, and the effective resistivity. The latter is significantly enhanced over its classical values in the collisionless limit. This generalized Sweet-Parker model also applies to the case in which a unidirectional, sizable third magnetic component is present. (C) 1999 American Institute of Physics. [S1070-664X(99)92105-5]. C1 Princeton Univ, Plasma Phys Lab, Princeton, NJ 08543 USA. RP Ji, HT (reprint author), Princeton Univ, Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. RI Carter, Troy/E-7090-2010; Yamada, Masaaki/D-7824-2015; OI Carter, Troy/0000-0002-5741-0495; Yamada, Masaaki/0000-0003-4996-1649; Hsu, Scott/0000-0002-6737-4934 NR 26 TC 43 Z9 43 U1 0 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1999 VL 6 IS 5 BP 1743 EP 1750 DI 10.1063/1.873432 PN 2 PG 8 WC Physics, Fluids & Plasmas SC Physics GA 190ND UT WOS:000079969500009 ER PT J AU Hesse, M Schindler, K Birn, J Kuznetsova, M AF Hesse, M Schindler, K Birn, J Kuznetsova, M TI The diffusion region in collisionless magnetic reconnection SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 40th Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 16-20, 1998 CL NEW ORLEANS, LOUISIANA SP Amer Phys Soc, Div Plasma Phys ID PARTICLE SIMULATION; ELECTRON DISSIPATION; EARTHS MAGNETOPAUSE; CURRENT SHEETS; PLASMA; FIELD; DYNAMICS; LINE; LAW AB The structure of the dissipation region in collisionless magnetic reconnection is investigated by means of kinetic particle-in-cell simulations and analytical theory. Analyses of simulations of reconnecting current sheets without guide magnetic field, which keep all parameters fixed with the exception of the electron mass, exhibit very similar large scale evolutions and time scales. A detailed comparison of two runs with different electron masses reveals very similar large scale parameters, such as ion flow velocities and magnetic field structures. The electron-scale phenomena in the reconnection region proper, however, appear to be quite different. The scale lengths of these processes are best organized by the trapping length of bouncing electrons in a field reversal region. The dissipation is explained by the electric field generated by nongyrotropic electron pressure tensor effects. In the reconnection region, the relevant electron pressure tensor components exhibit gradients which are independent of the electron mass. The similarities of the gradients as well as the behavior of the electron flow velocity can be derived from the electron trapping scale and the electron mass independence of the reconnection electric field. A further model which includes a significant guide magnetic field exhibits almost identical behavior. The explanation of this result lies in a Hall-type electric field which locally eliminates the magnetizing effect on the electrons of the guide magnetic field. The resulting electron dynamics is nearly identical to the one found in the model without guide magnetic field. This result strongly supports the hypothesis that the local physics in the dissipation region adjusts itself to the demands of the large-scale evolution. A further verification of this notion is provided by Hall-magnetohydrodynamic simulations which employ simple resistive dissipation models in otherwise similar large-scale models. These results also pertain to the inclusion of local reconnection physics in larger scale simulation models. (C) 1999 American Institute of Physics. [S1070-664X(99)97405-0]. C1 NASA, Goddard Space Flight Ctr, Electrodynam Branch, Greenbelt, MD 20771 USA. Ruhr Univ Bochum, D-44780 Bochum, Germany. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. NASA, Goddard Space Flight Ctr, Raytheon STX, Greenbelt, MD 20771 USA. RP Hesse, M (reprint author), NASA, Goddard Space Flight Ctr, Electrodynam Branch, Greenbelt, MD 20771 USA. RI Hesse, Michael/D-2031-2012; Kuznetsova, Maria/F-6840-2012 NR 46 TC 250 Z9 254 U1 0 U2 14 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1999 VL 6 IS 5 BP 1781 EP 1795 DI 10.1063/1.873436 PN 2 PG 15 WC Physics, Fluids & Plasmas SC Physics GA 190ND UT WOS:000079969500013 ER PT J AU Park, W Belova, EV Fu, GY Tang, XZ Strauss, HR Sugiyama, LE AF Park, W Belova, EV Fu, GY Tang, XZ Strauss, HR Sugiyama, LE TI Plasma simulation studies using multilevel physics models SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 40th Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 16-20, 1998 CL NEW ORLEANS, LOUISIANA SP Amer Phys Soc, Div Plasma Phys ID GYROKINETIC SIMULATION; ALFVEN EIGENMODE; PELLET INJECTION; MAGNETOHYDRODYNAMICS; TOKAMAKS AB The question of how to proceed toward ever more realistic plasma simulation studies using ever increasing computing power is addressed. The answer presented here is the M3D (Multilevel 3D) project, which has developed a code package with a hierarchy of physics levels that resolve increasingly complete subsets of phase-spaces and are thus increasingly more realistic. The rationale for the multilevel physics models is given. Each physics level is described and examples of its application are given. The existing physics levels are fluid models (3D configuration space), namely magnetohydrodynamic (MHD) and two-fluids; and hybrid models, namely gyrokinetic-energetic-particle/MHD (5D energetic particle phase-space), gyrokinetic-particle-ion/ fluid-electron (5D ion phase-space), and full-kinetic-particle-ion/fluid-electron level (6D ion phase-space). Resolving electron phase-space (5D or 6D) remains a future project. Phase-space-fluid models are not used in favor of delta f particle models. A practical and accurate nonlinear fluid closure for noncollisional plasmas seems not likely in the near future. (C) 1999 American Institute of Physics. [S1070-664X(99)93005-7]. C1 Princeton Univ, Plasma Phys Lab, Princeton, NJ 08544 USA. NYU, New York, NY USA. MIT, Cambridge, MA 02139 USA. RP Park, W (reprint author), Princeton Univ, Plasma Phys Lab, Princeton, NJ 08544 USA. NR 28 TC 145 Z9 146 U1 3 U2 19 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1999 VL 6 IS 5 BP 1796 EP 1803 DI 10.1063/1.873437 PN 2 PG 8 WC Physics, Fluids & Plasmas SC Physics GA 190ND UT WOS:000079969500014 ER PT J AU Isler, RC Brooks, NH West, WP Porter, GD AF Isler, RC Brooks, NH West, WP Porter, GD CA DIII-D Divertor Team TI Carbon flows in attached divertor plasmas SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 40th Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 16-20, 1998 CL NEW ORLEANS, LOUISIANA SP Amer Phys Soc, Div Plasma Phys ID SCRAPE-OFF LAYER; TRANSPORT; REVERSAL AB Parallel flow velocities of carbon ions in the DIII-D divertor [J. Luxon et al., Plasma Physics Controlled Nuclear Fusion Research, 1986 (International Atomic Energy Agency, Vienna, 1987), Vol. I, p. 159; S. L. Allen et al., Controlled Fusion and Plasma Physics, 1987 (Proc. 24th European Conf. Berchtesgaden, 1997), Vol. 21 A, Part III, p. 1129] have been studied under various operating conditions: L-mode (low-confinement mode), H-mode (high-confinement mode) with low-frequency ELMs (edge-localized modes), and H-mode with high-frequency ELMs. Both normal and reversed flows (toward the target plate and away from the target plate, respectively) are observed under all conditions, with the reversed speeds being as much as a factor of four greater than normal speeds. Magnitudes are approximately the same for L-mode and H-mode operation with high-frequency ELMs. In H-mode conditions with low-frequency ELMs, normal velocities are frequently observed to decline while reversed velocities increase in comparison to the other two conditions. (C) 1999 American Institute of Physics. [S1070-664X(99)90505-0]. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Gen Atom Co, San Diego, CA 92186 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 95540 USA. RP Isler, RC (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. OI Isler, Ralph/0000-0002-5368-7200 NR 18 TC 7 Z9 7 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1999 VL 6 IS 5 BP 1837 EP 1842 DI 10.1063/1.873442 PN 2 PG 6 WC Physics, Fluids & Plasmas SC Physics GA 190ND UT WOS:000079969500019 ER PT J AU Rognlien, TD Ryutov, DD Mattor, N Porter, GD AF Rognlien, TD Ryutov, DD Mattor, N Porter, GD TI Two-dimensional electric fields and drifts near the magnetic separatrix in divertor tokamaks SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 40th Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 16-20, 1998 CL NEW ORLEANS, LOUISIANA SP Amer Phys Soc, Div Plasma Phys ID DIII-D TOKAMAK; TRANSPORT; PLASMA; TURBULENCE; NEUTRALS; CURRENTS; MODELS AB A two-dimensional calculation is presented for the transport of plasma in the edge region of a divertor tokamak solving continuity, momentum, and energy balance fluid equations. The model uses classical processes of parallel transport along the magnetic field and cross-field drifts together with anomalous radial diffusion, including perpendicular ion viscosity. The self-consistent electrostatic potential is calculated on both sides of the magnetic separatrix via quasineutrality and current continuity. Outside the separatrix, the model extends to material divertor plates where the incident plasma is recycled as neutral gas and where the plate sheath and parallel currents dominate the potential structure. Inside the separatrix, various radial current terms-from anomalous viscosity, collisional damping, inertia, and del B drifts-contribute to determining the potential. The model rigorously enforces cancellation of gyroviscous and magnetization terms from the transport equations. The results emphasize the importance of E x B particle flow under the X-point which depends on the sign of the toroidal magnetic field. Radial electric field profiles at the outer midplane show strong variation with the magnitude of the anomalous diffusion coefficients and the core toroidal rotation velocity, indicating that shear stabilization of edge turbulence can likewise be sensitive to these parameters. (C) 1999 American Institute of Physics. [S1070-664X(99)91705-6]. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Rognlien, TD (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 25 TC 75 Z9 75 U1 2 U2 5 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1999 VL 6 IS 5 BP 1851 EP 1857 DI 10.1063/1.873488 PN 2 PG 7 WC Physics, Fluids & Plasmas SC Physics GA 190ND UT WOS:000079969500021 ER PT J AU Hirshman, SP Spong, DA Whitson, JC Nelson, B Batchelor, DB Lyon, JF Sanchez, R Brooks, A Fu, GY Goldston, RJ Ku, LP Monticello, DA Mynick, H Neilson, GH Pomphrey, N Redi, M Reiersen, W Reiman, AH Schmidt, J White, R Zarnstorff, MC Miner, WH Valanju, RM Boozer, A AF Hirshman, SP Spong, DA Whitson, JC Nelson, B Batchelor, DB Lyon, JF Sanchez, R Brooks, A Fu, GY Goldston, RJ Ku, LP Monticello, DA Mynick, H Neilson, GH Pomphrey, N Redi, M Reiersen, W Reiman, AH Schmidt, J White, R Zarnstorff, MC Miner, WH Valanju, RM Boozer, A TI Physics of compact stellarators SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 40th Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 16-20, 1998 CL NEW ORLEANS, LA SP Amer Phys Soc, Div Plasma Phys ID BOOTSTRAP CURRENT; TRANSPORT; CONFIGURATIONS; OPTIMIZATION; TORSATRON; DEVICES; TOKAMAK; PLASMA AB Recent progress in the theoretical understanding and design of compact stellarators is described. Hybrid devices, which depart from canonical stellarators by deriving benefits from the bootstrap current which flows at finite beta, comprise a class of low aspect ratio A<4 stellarators. They possess external kink stability (at moderate beta) in the absence of a conducting wall, possible immunity to disruptions through external control of the transform and magnetic shear, and they achieve volume-averaged ballooning beta limits (4%-6%) similar to those in tokamaks. In addition, bootstrap currents can reduce the effects of magnetic islands (self-healing effect) and lead to simpler stellarator coils by reducing the required external transform. Powerful physics and coil optimization codes have been developed and integrated to design experiments aimed at exploring compact stellarators. The physics basis for designing the national compact stellarator will be discussed. [S1070-664X(99)95405-8]. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. Univ Texas, Austin, TX 78712 USA. Columbia Univ, Dept Appl Phys, New York, NY 10027 USA. RP Hirshman, SP (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RI Sanchez, Raul/C-2328-2008; pomphrey, neil/G-4405-2010; Spong, Donald/C-6887-2012; White, Roscoe/D-1773-2013 OI Spong, Donald/0000-0003-2370-1873; White, Roscoe/0000-0002-4239-2685 NR 32 TC 23 Z9 23 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 1070-664X EI 1089-7674 J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1999 VL 6 IS 5 BP 1858 EP 1864 DI 10.1063/1.873489 PN 2 PG 7 WC Physics, Fluids & Plasmas SC Physics GA 190ND UT WOS:000079969500022 ER PT J AU Kinsey, JE Waltz, RE DeBoo, JC AF Kinsey, JE Waltz, RE DeBoo, JC TI Perturbative tests of theoretical transport models using cold pulse and modulated electron cyclotron heating experiments SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 40th Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 16-20, 1998 CL NEW ORLEANS, LOUISIANA SP Amer Phys Soc, Div Plasma Phys ID TEXAS-EXPERIMENTAL-TOKAMAK; ANOMALOUS TRANSPORT; ENERGY CONFINEMENT; H-MODE; TFTR; INJECTION; FACILITY; PLASMAS AB It is difficult to discriminate between various tokamak transport models using standardized statistical measures to assess the goodness of fit with steady-state density and temperature profiles in tokamaks. This motivates consideration of transient transport experiments as a technique for testing the temporal response predicted by models. Results are presented comparing the predictions from the Institute for Fusion Studies-Princeton Plasma Physics Laboratory (IFS/PPPL), gyro-Landau-fluid (GLF23), Multi-mode (MM), Current Diffusive Ballooning Mode (CDBM), and Mixed-shear (MS) transport models against data from ohmic cold pulse and modulated electron cyclotron heating (ECH) experiments. In ohmically heated discharges with rapid edge cooling due to trace impurity injection, it is found that critical gradient models containing a strong temperature ratio (T-i/T-e) dependence can exhibit behavior that is qualitatively consistent both spatially and temporally with experimental observation while depending solely on local parameters. On the DIII-D tokamak [J. L. Luxon and L. G. Davis, Fusion Technol. 8, 441 (1985)], off-axis modulated ECH experiments have been conducted in L-mode (low confinement mode) and the perturbed electron and ion temperature response to multiple heat pulses has been measured across the plasma core. Comparing the predicted Fourier phase of the temperature perturbations, it is found that no single model yielded agreement with both electron and ion phases for all cases. In general, it was found that the IFS/PPPL, GLF23, and MS models agreed well with the ion response, but not with the electron response. The CDBM and MM models agreed well with the electron response, but not with the ion response. For both types of transient experiments, temperature coupling between the electron and ion transport is found to be an essential feature needed in the models for reproducing the observed perturbative response. (C) 1999 American Institute of Physics. [S1070-664X(99)90105-2]. C1 Gen Atom Co, San Diego, CA 92186 USA. RP Kinsey, JE (reprint author), Oak Ridge Associated Univ, Oak Ridge, TN 37831 USA. NR 28 TC 8 Z9 8 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1999 VL 6 IS 5 BP 1865 EP 1871 DI 10.1063/1.873444 PN 2 PG 7 WC Physics, Fluids & Plasmas SC Physics GA 190ND UT WOS:000079969500023 ER PT J AU Bernabei, S Bell, MG Budny, R Darrow, D Fredrickson, ED Gorelenkov, N Hosea, JC Majeski, R Mazzucato, E Nazikian, R Phillips, CK Rogers, JH Schilling, G White, R Wilson, JR Zonca, F Zweben, S AF Bernabei, S Bell, MG Budny, R Darrow, D Fredrickson, ED Gorelenkov, N Hosea, JC Majeski, R Mazzucato, E Nazikian, R Phillips, CK Rogers, JH Schilling, G White, R Wilson, JR Zonca, F Zweben, S TI Role of Alfven instabilities in energetic ion transport SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 40th Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 16-20, 1998 CL NEW ORLEANS, LOUISIANA SP Amer Phys Soc, Div Plasma Phys ID TFTR; EIGENMODES; MODES; FLUCTUATIONS; PLASMAS AB Experiments with plasma heating by waves at the ion cyclotron resonance of a minority species have shown that the heating efficiency degrades above a certain power threshold. It is found that this threshold is due to the destabilization of a branch of shear Alfven waves, the Energetic Particle Modes, which causes a diffusive loss of fast ions. These modes not only play a fundamental role in the transport of the fast ions, but appear closely related to the formation of giant sawteeth. (C) 1999 American Institute of Physics. [S1070-664X(99)92305-4]. C1 Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. TRINITI, Troitsk 142092, Moscow, Russia. Intevac Inc, Santa Clara, CA 95054 USA. EURATOM Assoc, ENEA, CRE, I-00044 Frascati, Italy. RP Bernabei, S (reprint author), Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. RI White, Roscoe/D-1773-2013; Zonca, Fulvio/I-8236-2016 OI White, Roscoe/0000-0002-4239-2685; Zonca, Fulvio/0000-0002-9270-4704 NR 18 TC 27 Z9 27 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1999 VL 6 IS 5 BP 1880 EP 1884 DI 10.1063/1.873446 PN 2 PG 5 WC Physics, Fluids & Plasmas SC Physics GA 190ND UT WOS:000079969500025 ER PT J AU Carreras, BA van Milligen, BP Pedrosa, MA Balbin, R Hidalgo, C Newman, DE Sanchez, E Bravenec, R McKee, G Garcia-Cortes, I Bleuel, J Endler, M Riccardi, C Davies, S Matthews, GF Martines, E Antoni, V AF Carreras, BA van Milligen, BP Pedrosa, MA Balbin, R Hidalgo, C Newman, DE Sanchez, E Bravenec, R McKee, G Garcia-Cortes, I Bleuel, J Endler, M Riccardi, C Davies, S Matthews, GF Martines, E Antoni, V TI Experimental evidence of long-range correlations and self-similarity in plasma fluctuations SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 40th Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 16-20, 1998 CL NEW ORLEANS, LA SP Amer Phys Soc, Div Plasma Phys ID VELOCITY SHEAR-LAYER; ORGANIZED CRITICALITY; TURBULENT TRANSPORT; FRACTAL DIMENSION; EDGE TURBULENCE; TIME-SERIES; DYNAMICS; AVALANCHES; SANDPILES AB To better understand long time transport dynamics, techniques to investigate long-range dependences in plasma fluctuations have been applied to data from several confinement devices including tokamaks, stellarators, and reversed field pinch. The results reveal the self-similar character of the edge plasma fluctuations. This implies that the tail of the autocorrelation function decays as a power law and suggests that there is a superdiffusive component of the anomalous transport. Rescaled fluctuation and turbulent flux spectra from different devices also show a strong similarity. For a range of parameters corresponding to the tokamak ohmic regime and equivalent power for other devices, the spectral decay index may show a universal character. [S1070-664X(99)92405-9]. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Asoc Euratom Ciemat, Madrid 28040, Spain. Univ Texas Austin, Austin, TX USA. Univ Wisconsin Gen Atom, San Diego, CA 92186 USA. EURATOM, Max Planck Inst Plasmaphys, D-85740 Garching, Germany. Univ Milan, Dipartimento Fis, Milan, Italy. JET Joint Undertaking, Abingdon OX14 3EA, Oxon, England. Consorzio RFX, Padua, Italy. RP Carreras, BA (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RI Martines, Emilio/B-1418-2009; van Milligen, Boudewijn/H-5121-2015; Sanchez, Edilberto/D-4620-2009; Garcia-Cortes, Isabel/H-3341-2015; Balbin, Rosa/F-8210-2010; OI Martines, Emilio/0000-0002-4181-2959; van Milligen, Boudewijn/0000-0001-5344-6274; Sanchez, Edilberto/0000-0003-1062-7870; Garcia-Cortes, Isabel/0000-0002-5223-391X; Balbin, Rosa/0000-0001-5231-1300; antoni, vanni/0000-0002-4588-8168 NR 34 TC 55 Z9 54 U1 1 U2 1 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1999 VL 6 IS 5 BP 1885 EP 1892 DI 10.1063/1.873490 PN 2 PG 8 WC Physics, Fluids & Plasmas SC Physics GA 190ND UT WOS:000079969500026 ER PT J AU Garofalo, AM Turnbull, AD Strait, EJ Austin, ME Bialek, J Chu, MS Fredrickson, E La Haye, RJ Navratil, GA Lao, LL Lazarus, EA Okabayashi, M Rice, BW Sabbagh, SA Scoville, JT Taylor, TS Walker, ML AF Garofalo, AM Turnbull, AD Strait, EJ Austin, ME Bialek, J Chu, MS Fredrickson, E La Haye, RJ Navratil, GA Lao, LL Lazarus, EA Okabayashi, M Rice, BW Sabbagh, SA Scoville, JT Taylor, TS Walker, ML CA DII-D Team TI Stabilization of the external kink and control of the resistive wall mode in tokamaks SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 40th Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 16-20, 1998 CL NEW ORLEANS, LOUISIANA SP Amer Phys Soc, Div Plasma Phys ID HIGH-BETA; PLASMA ROTATION; DIII-D; INSTABILITIES; SHELL AB One promising approach to maintaining stability of high beta tokamak plasmas is the use of a conducting wall near the plasma to stabilize low-n ideal magnetohydrodynamic instabilities. However, with a resistive wall, either plasma rotation or active feedback control is required to stabilize the more slowly growing resistive wall modes (RWMs). Previous experiments have demonstrated that plasmas with a nearby conducting wall can remain stable to the n=1 ideal external kink above the beta limit predicted with the wall at infinity. Recently, extension of the wall stabilized lifetime tau(L) to more than 30 times the resistive wall time constant tau(w) and detailed, reproducible observation of the n=1 RWM have been possible in DIII-D [Plasma Physics and Controlled Fusion Research (International Atomic Energy Agency, Vienna, 1986), p. 159] plasmas above the no-wall beta limit. The DIII-D measurements confirm characteristics common to several RWM theories. The mode is destabilized as the plasma rotation at the q=3 surface decreases below a critical frequency of 1-7 kHz (similar to 1% of the toroidal Alfven frequency). The measured mode growth times of 2-8 ms agree with measurements and numerical calculations of the dominant DIII-D vessel eigenmode time constant tw. From its onset, the RWM has little or no toroidal rotation (omega(mode) less than or equal to tau(w)(-1) much less than omega(plasma)), and rapidly reduces the plasma rotation to zero. These slowly growing RWMs can in principle be destabilized using external coils controlled by a feedback loop. In this paper, the encouraging results from the first open loop experimental tests of active control of the RWM, conducted in DIII-D, are reported. (C) 1999 American Institute of Physics. [S1070-664X(99)92705-2]. C1 Columbia Univ, New York, NY 10027 USA. Gen Atom Co, San Diego, CA 92186 USA. Univ Texas, Austin, TX 78712 USA. Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Garofalo, AM (reprint author), Columbia Univ, New York, NY 10027 USA. RI Sabbagh, Steven/C-7142-2011; OI Walker, Michael/0000-0002-4341-994X NR 21 TC 59 Z9 59 U1 0 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1999 VL 6 IS 5 BP 1893 EP 1898 DI 10.1063/1.873495 PN 2 PG 6 WC Physics, Fluids & Plasmas SC Physics GA 190ND UT WOS:000079969500027 ER PT J AU Goetz, JA LaBombard, B Lipschultz, B Pitcher, CS Terry, JL Boswell, C Gangadhara, S Pappas, D Weaver, J Welch, B Boivin, RL Bonoli, P Fiore, C Granetz, R Greenwald, M Hubbard, A Hutchinson, I Irby, J Marmar, E Mossessian, D Porkolab, M Rice, J Rowan, WL Schilling, G Snipes, J Takase, Y Wolfe, S Wukitch, S AF Goetz, JA LaBombard, B Lipschultz, B Pitcher, CS Terry, JL Boswell, C Gangadhara, S Pappas, D Weaver, J Welch, B Boivin, RL Bonoli, P Fiore, C Granetz, R Greenwald, M Hubbard, A Hutchinson, I Irby, J Marmar, E Mossessian, D Porkolab, M Rice, J Rowan, WL Schilling, G Snipes, J Takase, Y Wolfe, S Wukitch, S TI High confinement dissipative divertor operation on Alcator C-Mod SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 40th Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 16-20, 1998 CL NEW ORLEANS, LOUISIANA SP Amer Phys Soc, Div Plasma Phys ID GAS TARGETS; PLASMAS; TOKAMAK; ASDEX; RECOMBINATION; EXHAUST; PHYSICS; JT-60U; REGIME AB Alcator C-Mod [I. H. Hutchinson et al., Phys. Plasmas 1, 1511 (1994)] has operated a High-confinement-mode (H-mode) plasma together with a dissipative divertor and low core Z(eff). The initially attached plasma is characterized by steady-state enhancement factor, H-ITER89P [P. N. Yushmanov et al., Nucl. Fusion 30, 1999 (1990)], of 1.9, central Z(eff) of 1.1, and a radiative fraction of similar to 50%. Feedback control of a nitrogen gas puff is used to increase radiative losses in both the core/edge and divertor plasmas in almost equal amounts. Simultaneously, the core plasma maintains H-ITER89P of 1.6 and Z(eff) of 1.4 in this nearly 100% radiative state. The power and particle flux to the divertor plates have been reduced to very low levels while the core plasma is relatively unchanged by the dissipative nature of the divertor. (C) 1999 American Institute of Physics. [S1070-664X(99)93305-0]. C1 MIT, Plasma Sci & Fus Ctr, Cambridge, MA 02139 USA. Univ Maryland, Inst Plasma Res, College Pk, MD 20742 USA. Univ Texas, Fus Res Ctr, Austin, TX 78712 USA. Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Goetz, JA (reprint author), MIT, Plasma Sci & Fus Ctr, Cambridge, MA 02139 USA. RI Hutchinson, Ian/D-1136-2009; Lipschultz, Bruce/J-7726-2012; OI Hutchinson, Ian/0000-0003-4276-6576; Lipschultz, Bruce/0000-0001-5968-3684; Greenwald, Martin/0000-0002-4438-729X NR 45 TC 16 Z9 16 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1999 VL 6 IS 5 BP 1899 EP 1906 DI 10.1063/1.873447 PN 2 PG 8 WC Physics, Fluids & Plasmas SC Physics GA 190ND UT WOS:000079969500028 ER PT J AU Chang, CS Phillips, CK White, R Zweben, S Bonoli, PT Rice, JE Greenwald, MJ deGrassie, J AF Chang, CS Phillips, CK White, R Zweben, S Bonoli, PT Rice, JE Greenwald, MJ deGrassie, J TI Generation of plasma rotation by ion cyclotron resonance heating in tokamaks SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 40th Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 16-20, 1998 CL NEW ORLEANS, LOUISIANA SP Amer Phys Soc, Div Plasma Phys ID FUSION TEST REACTOR; TRANSPORT; DIFFUSION AB A physical mechanism for generation of a plasma rotation and radial electric field by ion cyclotron resonance heating (ICRH) is presented in a tokamak geometry. By breaking the omnigenity of resonant ion orbits, ICRH can induce a nonambipolar minor-radial transport of resonant ions. This yields a radial charge separation, a modification to radial electric field E-r, and the generation of plasma rotation. It is estimated that the ICRH fast-wave power available in the present-day tokamak experiments can be large enough to give a significant modification to plasma rotation. (C) 1999 American Institute of Physics. [S1070-664X(99)95105-4]. C1 NYU, New York, NY 10012 USA. Korea Adv Inst Sci & Technol, Seoul, South Korea. Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. MIT, Plasma Sci & Fus Ctr, Cambridge, MA 02139 USA. Gen Atom Co, San Diego, CA 92138 USA. RP Chang, CS (reprint author), NYU, 550 1st Ave, New York, NY 10012 USA. RI White, Roscoe/D-1773-2013; OI White, Roscoe/0000-0002-4239-2685; Greenwald, Martin/0000-0002-4438-729X NR 18 TC 42 Z9 44 U1 1 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1999 VL 6 IS 5 BP 1969 EP 1977 DI 10.1063/1.873453 PN 2 PG 9 WC Physics, Fluids & Plasmas SC Physics GA 190ND UT WOS:000079969500036 ER PT J AU Stallard, BW Greenfield, CM Staebler, GM Rettig, CL Chu, MS Austin, ME Baker, DR Baylor, LR Burrell, KH DeBoo, JC deGrassie, JS Doyle, EJ Lohr, J McKee, GR Miller, RL Peebles, WA Petty, CC Pinsker, RI Rice, BW Rhodes, TL Waltz, RE Zeng, L AF Stallard, BW Greenfield, CM Staebler, GM Rettig, CL Chu, MS Austin, ME Baker, DR Baylor, LR Burrell, KH DeBoo, JC deGrassie, JS Doyle, EJ Lohr, J McKee, GR Miller, RL Peebles, WA Petty, CC Pinsker, RI Rice, BW Rhodes, TL Waltz, RE Zeng, L CA DIII-D Team TI Electron heat transport in improved confinement discharges in DIII-D SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 40th Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 16-20, 1998 CL NEW ORLEANS, LOUISIANA SP Amer Phys Soc, Div Plasma Phys ID FINITE ASPECT RATIO; MAGNETIC SHEAR; PLASMA; TOKAMAK; MODEL; RECONSTRUCTION; INSTABILITIES; TURBULENCE; BARRIER AB In DIII-D [J. L. Luxon and L. G. Davis, Fusion Technol. 8, 441 (1985)] tokamak plasmas with an internal transport barrier (ITB), the comparison of gyrokinetic linear stability (GKS) predictions with experiments in both low and strong negative magnetic shear plasmas provide improved understanding for electron thermal transport within the plasma. Within a limited region just inside the ITB, the electron temperature gradient (ETG) modes appear to control the electron temperature gradient and, consequently, the electron thermal transport. The increase in the electron temperaturegradient with more strongly negative magnetic shear is consistent with the increase in the ETG mode marginal gradient. Closer to the magnetic axis the T-e profile flattens and the ETG modes are predicted to be stable. With additional core electron heating, FIR scattering measurements near the axis show the presence of high k fluctuations (12 cm(-1)), rotating in the electron diamagnetic drift direction. This turbulence could impact electron transport and possibly also ion transport. Thermal diffusivities for electrons, and to a lesser degree ions, increase. The ETG mode can exist at this wave number, but it is computed to be robustly stable near the axis. Consequently, in the plasmas we have examined, calculations of drift wave linear stability do not explain the observed transport near the axis in plasmas with or without additional electron heating, and there are probably other processes controling transport in this region. (C) 1999 American Institute of Physics. [S1070-664X(99)95505-2]. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Gen Atom Co, San Diego, CA 92186 USA. Univ Calif Los Angeles, Los Angeles, CA USA. Univ Texas, Austin, TX 78712 USA. Oak Ridge Natl Lab, Oak Ridge, TN USA. Univ Wisconsin, Madison, WI USA. RP Stallard, BW (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 29 TC 84 Z9 84 U1 1 U2 4 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1999 VL 6 IS 5 BP 1978 EP 1984 DI 10.1063/1.873494 PN 2 PG 7 WC Physics, Fluids & Plasmas SC Physics GA 190ND UT WOS:000079969500037 ER PT J AU Hillis, DL Hogan, JT Andrew, P Coad, JP Ehrenberg, JK Houlberg, WA von Hellermann, M Horton, LD Matthews, GF Monk, RD Morgan, PD Stamp, MF Zastrow, KD AF Hillis, DL Hogan, JT Andrew, P Coad, JP Ehrenberg, JK Houlberg, WA von Hellermann, M Horton, LD Matthews, GF Monk, RD Morgan, PD Stamp, MF Zastrow, KD TI Investigation of tritium pathways in the Joint European Torus (JET) tokamak SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 40th Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 16-20, 1998 CL NEW ORLEANS, LOUISIANA SP Amer Phys Soc, Div Plasma Phys ID PLASMAS; WALL AB The neutral tritium concentration in the subdivertor region of JET [P.-H. Rebut, R. J. Bickerton, and B. E. Keen, Nucl. Fusion 25, 1011 (1985)] is measured during deuterium-to-tritium changeover experiments with a novel species-selective Penning gauge coupled to a high-resolution spectrometer. The subdivertor measurements, when compared with edge and strike point values, are a sensitive characterization of the status of the wall saturation. The neutral transport code (EIRENE) [D. Reiter, Forschungszentrum, Juelich: Report Juel-2599 (1992)] and a wall hydrogen trapping and diffusion code (WDIFFUSE) [J. Hogan, R. Maingi, P. Mioduszewski et al., J. Nucl. Mater. 241, 612 (1997)] evaluate the wall tritium recycling coefficients (R-T) and compare them with quantitative, testable models for the dynamic exchange between recycling surfaces and the edge/pedestal region. Using the dynamic inventory model, tritium transport following the injection of trace amounts of tritium has been investigated for JET high-confinement mode (H-mode) discharges with Edge Localized Modes (ELMs). Upon explicitly treating the ELMs as instantaneous magnetohydrodynamic events, residual (intra-ELM) radial diffusivities are reduced and can be compared with neoclassical levels. (C) 1999 American Institute of Physics. [S1070-664X(99)95805-6]. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Jet Joint Undertaking, Abingdon OX14 3EA, Oxon, England. RP Hillis, DL (reprint author), Oak Ridge Natl Lab, POB 2009, Oak Ridge, TN 37831 USA. NR 29 TC 5 Z9 5 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1999 VL 6 IS 5 BP 1985 EP 1994 DI 10.1063/1.873454 PN 2 PG 10 WC Physics, Fluids & Plasmas SC Physics GA 190ND UT WOS:000079969500038 ER PT J AU Cohen, RH Ryutov, D AF Cohen, RH Ryutov, D TI Drifts, boundary conditions and convection on open field lines SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 40th Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 16-20, 1998 CL NEW ORLEANS, LOUISIANA SP Amer Phys Soc, Div Plasma Phys ID SCRAPE-OFF LAYER; TILTED MAGNETIC-FIELD; DIVERTOR PLASMA; TOKAMAK; SHEATH; INSTABILITY; ASYMMETRIES; TRANSITION; SURFACE; TARGET AB In a number of plasmas of practical interest, including the scrape-off layer of a tokamak with a divertor or toroidal limiter, some gas discharge devices, and in the vicinity of spacecraft, magnetic field lines intersect bounding surfaces at shallow angles. Under these circumstances a number of interesting and important effects arise. Drifts can compete with parallel flows in establishing the boundary conditions for plasma mass-flow and current (sheath current-voltage characteristics). This paper derives the mass-flow constraints including both poloidal and radial drifts, reviews the current boundary conditions, and surveys the consequences, including along-field density and heat-flux asymmetries, convection created by a wavy surface, generation of electric fields, and surface currents associated with shadows from surface structures, and modification of instability growth rates. (C) 1999 American Institute of Physics. [S1070-664X(99)96505-9]. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Cohen, RH (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 32 TC 13 Z9 13 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1999 VL 6 IS 5 BP 1995 EP 2001 DI 10.1063/1.873455 PN 2 PG 7 WC Physics, Fluids & Plasmas SC Physics GA 190ND UT WOS:000079969500039 ER PT J AU Menard, J Majeski, R Kaita, R Ono, M Munsat, T Stutman, D Finkenthal, M AF Menard, J Majeski, R Kaita, R Ono, M Munsat, T Stutman, D Finkenthal, M TI High-harmonic fast magnetosonic wave coupling, propagation, and heating in a spherical torus plasma SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 40th Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 16-20, 1998 CL NEW ORLEANS, LOUISIANA SP Amer Phys Soc, Div Plasma Phys ID ASPECT-RATIO TOKAMAKS; HIGH-BETA PLASMAS; DIII-D TOKAMAK; CURRENT DRIVE; ICRF ANTENNAS; ABSORPTION; ELECTRONS; SYSTEM; POWER; START AB A novel rotatable two-strap antenna has been installed in the current drive experiment upgrade (CDX-U) [T. Jones, Ph. D. thesis, Princeton University (1995)] in order to investigate high-harmonic fast wave coupling, propagation, and electron heating as a function of strap angle and strap phasing in a spherical torus plasma. Radio-frequency-driven sheath effects are found to fit antenna loading trends at very low power and become negligible above a few kilowatts. At sufficiently high power, the measured coupling efficiency as a function of strap angle is found to agree favorably with cold plasma wave theory. Far-forward microwave scattering from wave-induced density fluctuations in the plasma core tracks the predicted fast wave loading as the antenna is rotated. Signs of electron heating during rf power injection have been observed in CDX-U with central Thomson scattering, impurity ion spectroscopy, and Langmuir probes. While these initial results appear promising, damping of the fast wave on thermal ions at high ion-cyclotron-harmonic number may compete with electron damping at sufficiently high ion beta-possibly resulting in a significantly reduced current drive efficiency and production of a fast ion population. Preliminary results from ray-tracing calculations which include these ion damping effects are presented. (C) 1999 American Institute of Physics. [S1070-664X(99)97305-6]. C1 Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. Johns Hopkins Univ, Baltimore, MD 21205 USA. RP Menard, J (reprint author), Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. RI Stutman, Dan/P-4048-2015; OI Menard, Jonathan/0000-0003-1292-3286 NR 43 TC 28 Z9 28 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1999 VL 6 IS 5 BP 2002 EP 2008 DI 10.1063/1.873483 PN 2 PG 7 WC Physics, Fluids & Plasmas SC Physics GA 190ND UT WOS:000079969500040 ER PT J AU Dimonte, G AF Dimonte, G TI Nonlinear evolution of the Rayleigh-Taylor and Richtmyer-Meshkov instabilities SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 40th Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 16-20, 1998 CL NEW ORLEANS, LOUISIANA SP Amer Phys Soc, Div Plasma Phys ID RADIATIVELY DRIVEN SHOCKS; ELASTIC-PLASTIC SOLIDS; ACCELERATION INSTABILITY; COMPRESSIBLE FLUIDS; MAGNETIC-FIELD; BUBBLE MERGER; STABILITY; MODEL; INTERFACE; SIMULATIONS AB Scaled experiments on the nonlinear Rayleigh-Taylor (RT) and Richtmyer-Meshkov (RM) instabilities are described for two limiting conditions. First, at high Reynolds number, the mixing layer is found to grow self-similarly similar to a(i)Agt(2) for a constant acceleration and as a power law t(theta i) for an impulsive acceleration g=U delta(t). The growth coefficients alpha(i) and exponents theta(i) are measured over a comprehensive range of Atwood number A. Second, with non-Newtonian materials, the critical wavelength and amplitude for RT instability associated with the shear modulus and tensile yield of the material is observed over a variety of conditions. The results are applied to naturally occurring supernova explosions and volcanic islands. [S1070-664X(99)90405-6]. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Dimonte, G (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 84 TC 70 Z9 72 U1 3 U2 14 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1999 VL 6 IS 5 BP 2009 EP 2015 DI 10.1063/1.873491 PN 2 PG 7 WC Physics, Fluids & Plasmas SC Physics GA 190ND UT WOS:000079969500041 ER PT J AU Nash, TJ Derzon, MS Chandler, GA Leeper, R Fehl, D Lash, J Ruiz, C Cooper, G Seaman, JF McGurn, J Lazier, S Torres, J Jobe, D Gilliland, T Hurst, M Mock, R Ryan, P Nielsen, D Armijo, J McKenney, J Hawn, R Hebron, D MacFarlane, JJ Petersen, D Bowers, R Matuska, W Ryutov, DD AF Nash, TJ Derzon, MS Chandler, GA Leeper, R Fehl, D Lash, J Ruiz, C Cooper, G Seaman, JF McGurn, J Lazier, S Torres, J Jobe, D Gilliland, T Hurst, M Mock, R Ryan, P Nielsen, D Armijo, J McKenney, J Hawn, R Hebron, D MacFarlane, JJ Petersen, D Bowers, R Matuska, W Ryutov, DD TI High-temperature dynamic hohlraums on the pulsed power driver Z SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 40th Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 16-20, 1998 CL NEW ORLEANS, LOUISIANA SP Amer Phys Soc, Div Plasma Phys ID Z-PINCHES; DENSITY; IMPLOSIONS; FUSION AB In the concept of the dynamic hohlraum an imploding Z pinch is optically thick to its own radiation. Radiation may be trapped inside the pinch to give a radiation temperature inside the pinch greater than that outside the pinch. The radiation is typically produced by colliding an outer Z-pinch liner onto an inner liner. The collision generates a strongly radiating shock, and the radiation is trapped by the outer liner. As the implosion continues after the collision, the radiation temperature may continue to increase due to ongoing PdV (pressure times change in volume) work done by the implosion. In principal, the radiation temperature may increase to the point at which the outer liner burns through, becomes optically thin, and no longer traps the radiation. One application of the dynamic hohlraum is to drive an ICF (inertial confinement fusion) pellet with the trapped radiation field. Members of the dynamic hohlraum team at Sandia National Labs have used the pulsed power driver Z (20 MA, 100 ns) to create a dynamic hohlraum with temperature linearly ramping from 100 to 180 eV over 5 ns. On this shot zp214 a nested tungsten wire array of 4 and 2 cm diam with masses of 2 and 1 mg imploded onto a 2.5 mg plastic annulus at 5 mm diam. The current return can on this shot was slotted. It is likely the radiation temperature may be increased to over 200 eV by stabilizing the pinch with a solid current return can. A current return can with nine slots imprints nine filaments onto the imploding pinch. This degrades the optical trapping and the quality of the liner collision. A 1.6 mm diam capsule situated inside this dynamic hohlraum of zp214 would see 15 kJ of radiation impinging on its surface before the pinch itself collapses to a 1.6 mm diam. Dynamic hohlraum shots including pellets were scheduled to take place on Z in September of 1998. (C) 1999 American Institute of Physics. [S1070-664X(99)90905-9]. C1 Sandia Natl Labs, Albuquerque, NM 87123 USA. Univ Wisconsin, Madison, WI 53705 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Nash, TJ (reprint author), Sandia Natl Labs, Albuquerque, NM 87123 USA. NR 20 TC 82 Z9 83 U1 2 U2 8 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1999 VL 6 IS 5 BP 2023 EP 2029 DI 10.1063/1.873457 PN 2 PG 7 WC Physics, Fluids & Plasmas SC Physics GA 190ND UT WOS:000079969500043 ER PT J AU Sanford, TWL Mock, RC Spielman, RB Haines, MG Chittenden, JP Whitney, KG Apruzese, JP Peterson, DL Greenly, JB Sinars, DB Reisman, DB Mosher, D AF Sanford, TWL Mock, RC Spielman, RB Haines, MG Chittenden, JP Whitney, KG Apruzese, JP Peterson, DL Greenly, JB Sinars, DB Reisman, DB Mosher, D TI Wire array Z-pinch insights for enhanced x-ray production SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 40th Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 16-20, 1998 CL NEW ORLEANS, LOUISIANA SP Amer Phys Soc, Div Plasma Phys ID POWER; SIMULATIONS; IMPLOSIONS; PLASMAS; SYMMETRY; CARBON; SATURN; FUSION; MODEL AB Comparisons of measured total radiated x-ray power from annular wire-array z-pinches with a variety of models as a function of wire number, array mass, and load radius are reviewed. The data, which are comprehensive, have provided important insights into the features of wire-array dynamics that are critical for high x-ray power generation. Collectively, the comparisons of the data with the model calculations suggest that a number of underlying dynamical mechanisms involving cylindrical asymmetries and plasma instabilities contribute to the measured characteristics. For example, under the general assumption that the measured risetime of the total-radiated-power pulse is related to the thickness of the plasma shell formed on axis, the Heuristic Model [IEEE Trans. Plasma Sci. 26, 1275 (1998)] agrees with the measured risetime under a number of specific assumptions about the way the breakdown of the wires, the wire-plasma expansion, and the Rayleigh-Taylor instability in the r-z plane, develop. Likewise, in the high wire-number regime (where the wires are calculated to form a plasma shell prior to significant radial motion of the shell) the comparisons show that the variation in the power of the radiation generated as a function of load mass and array radius can be simulated by the two-dimensional Eulerian-radiation-magnetohydrodynamics code (E-RMHC) [Phys. Plasmas 3, 368 (1996)], using a single random-density perturbation that seeds the Rayleigh-Taylor instability in the r-z plane. For a given pulse-power generator, the comparisons suggest that (1) the smallest interwire gaps compatible with practical load construction and (2) the minimum implosion time consistent with the optimum required energy coupling of the generator to the load should produce the highest total-radiated-power levels. (C) 1999 American Institute of Physics. [S1070-664X(99)91505-7]. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Univ London Imperial Coll Sci Technol & Med, Blackett Lab, London SW7 2BZ, England. USN, Res Lab, Radiat Hydrodynam Branch, Washington, DC 20375 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Cornell Univ, Plasma Studies Lab, Ithaca, NY 14853 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. USN, Res Lab, Pulsed Power Phys Branch, Washington, DC 20375 USA. RP Sanford, TWL (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 42 TC 27 Z9 27 U1 1 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1999 VL 6 IS 5 BP 2030 EP 2040 DI 10.1063/1.873458 PN 2 PG 11 WC Physics, Fluids & Plasmas SC Physics GA 190ND UT WOS:000079969500044 ER PT J AU Lasinski, BF Langdon, AB Hatchett, SP Key, MH Tabak, M AF Lasinski, BF Langdon, AB Hatchett, SP Key, MH Tabak, M TI Particle-in-cell simulations of ultra intense laser pulses propagating through overdense plasma for fast-ignitor and radiography applications SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 40th Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 16-20, 1998 CL NEW ORLEANS, LOUISIANA SP Amer Phys Soc, Div Plasma Phys AB Zohar (two-dimensions, particle-in-cell) [C. K. Birdsall and A. B. Langdon, Plasma Physics via Computer Simulation (McGraw-Hill, New York, 1985)] simulations of ultra intense laser beams boring into overdense plasmas whose parameters are guided by the fast-ignitor concept and radiography applications are presented. Complex low frequency magnetic field structures, narrow channel formation, and beam deflection are all evident. Particle tracking diagnostics elucidate the nature of the currents that produce and interact with these static magnetic fields which are larger than 10(9) G for simulations at 10(21) W/cm(2) in a 50n(c) plasma. Tracking electron orbits provides a more complete understanding of the hot electron generation as the short pulse, high intensity laser penetrates overdense plasma. Particles which constitute the current in the narrow channel are partially confined by the low frequency magnetic field. In contrast, the return current particles on the outside of the channel are defocused by the high magnetic field and move away from the channel. [S1070-664X(99)91605-1]. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Lasinski, BF (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 18 TC 74 Z9 74 U1 0 U2 5 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1999 VL 6 IS 5 BP 2041 EP 2047 DI 10.1063/1.873496 PN 2 PG 7 WC Physics, Fluids & Plasmas SC Physics GA 190ND UT WOS:000079969500045 ER PT J AU Labaune, C Baldis, HA Cohen, B Rozmus, W Depierreux, S Schifano, E Bauer, BS Michard, A AF Labaune, C Baldis, HA Cohen, B Rozmus, W Depierreux, S Schifano, E Bauer, BS Michard, A TI Nonlinear modification of laser-plasma interaction processes under crossed laser beams SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 40th Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 16-20, 1998 CL NEW ORLEANS, LOUISIANA SP Amer Phys Soc, Div Plasma Phys ID STIMULATED RAMAN-SCATTERING; INERTIAL CONFINEMENT FUSION; ION-ACOUSTIC-WAVES; BRILLOUIN-SCATTERING; PARAMETRIC-INSTABILITIES; HOMOGENEOUS PLASMA; UNDERDENSE PLASMAS; ENERGY-TRANSFER; LANGMUIR DECAY; SATURATION AB Effects of multiple crossed laser beams on stimulated Brillouin and Raman scattering (SBS and SRS) growth rates, as well as on the SBS and SRS competition, have been investigated in a preformed plasma using Thomson scattering of a short-wavelength probe beam. Reduction of the amplitude of ion acoustic waves (IAW) associated with SBS and amplification of the amplitude of electron plasma waves associated with SRS in the case of irradiation by two or three beams compared to a single beam are reported. Mechanisms by which crossed laser beams can reduce SBS by detuning the interaction or by nonlinearly enhancing the damping rate of the IAWs will be discussed. The same mechanisms could explain the enhancement of SRS backscatter through modified secondary decay processes of SRS. In a second experiment, nonlinear enhancement of extreme forward scattering of one laser beam going through a preformed plasma has been observed when a second interaction beam was present. The role of ion wave instabilities on forward scattering will be discussed, based on the spectral analysis of the forward scattered light. (C) 1999 American Institute of Physics. [S1070-664X(99)91205-3]. C1 Ecole Polytech, Lab Utilisat Lasers Intenses, F-91128 Palaiseau, France. Univ Paris 06, CNRS, LULI, F-75252 Paris 05, France. CEA, Paris, France. Univ Calif Lawrence Livermore Natl Lab, Inst Laser Sci & Applicat, Livermore, CA 94550 USA. Univ Alberta, Inst Theoret Phys, Edmonton, AB T6G 2G7, Canada. RP Labaune, C (reprint author), Ecole Polytech, Lab Utilisat Lasers Intenses, F-91128 Palaiseau, France. NR 51 TC 26 Z9 27 U1 1 U2 4 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1999 VL 6 IS 5 BP 2048 EP 2056 DI 10.1063/1.873459 PN 2 PG 9 WC Physics, Fluids & Plasmas SC Physics GA 190ND UT WOS:000079969500046 ER PT J AU Desjarlais, MP Marder, BM AF Desjarlais, MP Marder, BM TI Theory of wire number scaling in wire-array Z pinches SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 40th Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 16-20, 1998 CL NEW ORLEANS, LOUISIANA SP Amer Phys Soc, Div Plasma Phys ID RAYLEIGH-TAYLOR INSTABILITY; X-RAY POWER; HEURISTIC MODEL; THIN-LAYER; SIMULATIONS; IMPLOSIONS; REGIME; FLOW AB Pulsed-power-driven Z pinches, produced by imploding cylindrical arrays of many wires, have generated very high x-ray radiation powers (>200 TW) and energies (2 MJ). Experiments have revealed a steady improvement in Z-pinch performance with increasing wire number at fixed total mass and array radius. The dominant mechanism acting to limit the performance of these devices is believed to be the Rayleigh-Taylor instability which broadens the radially imploding plasma sheath and consequently reduces the peak radiation power. A model is presented which describes an amplification over the two-dimensional Rayleigh-Taylor growth rate brought about by kink-like forces on the individual wires. This amplification factor goes to zero as the number of wires approaches infinity. This model gives results which are in good agreement with the experimental data and provides a scaling for wire-array Z pinches. (C) 1999 American Institute of Physics. [S1070-664X(99)91905-5]. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Desjarlais, MP (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 34 TC 24 Z9 25 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1999 VL 6 IS 5 BP 2057 EP 2064 DI 10.1063/1.873460 PN 2 PG 8 WC Physics, Fluids & Plasmas SC Physics GA 190ND UT WOS:000079969500047 ER PT J AU Kane, J Arnett, D Remington, BA Glendinning, SG Bazan, G Drake, RP Fryxell, BA Teyssier, R Moore, K AF Kane, J Arnett, D Remington, BA Glendinning, SG Bazan, G Drake, RP Fryxell, BA Teyssier, R Moore, K TI Scaling supernova hydrodynamics to the laboratory SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 40th Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 16-20, 1998 CL NEW ORLEANS, LOUISIANA SP Amer Phys Soc, Div Plasma Phys ID RAYLEIGH-TAYLOR INSTABILITY; LINE-PROFILES; NOVA LASER; SN-1987A; DRIVEN; SHOCKS; 1987A; FLOW; PERTURBATIONS; EVOLUTION AB Supernova (SN) 1987A focused attention on the critical role of hydrodynamic instabilities in the evolution of supernovae. To test the modeling of these instabilities, we are developing laboratory experiments of hydrodynamic mixing under conditions relevant to supernovae. Initial results were reported in J. Kane et al. [Astrophys. J. 478, L75 (1997) and B. A. Remington et al., Phys. Plasmas 4, 1994 (1997)]. The Nova laser is used to generate a 10-15 Mbar shock at the interface of a two-layer planar target, which triggers perturbation growth due to the Richtmyer-Meshkov instability, and to the Rayleigh-Taylor instability as the interface decelerates. This resembles the hydrodynamics of the He-H interface of a Type II supernova at intermediate times, up to a few X 10(3) s. The scaling of hydrodynamics on microscopic laser scales to the SN-size scales is presented. The experiment is modeled using the hydrodynamics codes HYADES [J. T. Larson and S. M. Lane, J. Quant. Spect. Rad. Trans. 51, 179 (1994)] and CALE [R. T. Barton, Numerical Astrophysics (Jones and Bartlett, Boston, 1985), pp. 482-497], and the supernova code PROMETHEUS [P. R. Woodward and P. Collela, J. Comp. Phys. 54, 115 (1984)]. Results of the experiments and simulations are presented. Analysis of the spike-and-bubble velocities using potential flow theory and Ott thin-shell theory is presented, as well as a study of 2D versus 3D differences in perturbation growth at the He-H interface of SN 1987A. (C) 1999 American Institute of Physics. [S1070-664X(99)93205-6]. C1 Univ Arizona, Tucson, AZ 85721 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Michigan, Ann Arbor, MI 48109 USA. Univ Chicago, ASCI Flash Ctr, Chicago, IL 60637 USA. Ctr Etud Saclay Lorme des Merisiers, CEA, DSM, DAPNIA, F-91191 Gif Sur Yvette, France. Harvey Mudd Coll, Claremont, CA 91711 USA. RP Kane, J (reprint author), Univ Arizona, Tucson, AZ 85721 USA. RI Drake, R Paul/I-9218-2012 OI Drake, R Paul/0000-0002-5450-9844 NR 36 TC 40 Z9 41 U1 1 U2 12 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1999 VL 6 IS 5 BP 2065 EP 2071 DI 10.1063/1.873497 PN 2 PG 7 WC Physics, Fluids & Plasmas SC Physics GA 190ND UT WOS:000079969500048 ER PT J AU Deeney, C Coverdale, CA Douglas, MR Nash, TJ Spielman, RB Struve, KW Whitney, KG Thornhill, JW Apruzese, JP Clark, RW Davis, J Beg, FN Ruiz-Camacho, J AF Deeney, C Coverdale, CA Douglas, MR Nash, TJ Spielman, RB Struve, KW Whitney, KG Thornhill, JW Apruzese, JP Clark, RW Davis, J Beg, FN Ruiz-Camacho, J TI Titanium K-shell x-ray production from high velocity wire array implosions on the 20-MA Z accelerator SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 40th Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 16-20, 1998 CL NEW ORLEANS, LOUISIANA SP Amer Phys Soc, Div Plasma Phys ID Z-PINCH IMPLOSIONS; ALUMINUM; EMISSION; PLASMAS; POWER; OPTIMIZATION; INSTABILITY; SYMMETRY; YIELDS; ARGON AB The advent of the 20-MA Z accelerator [R. B. Spielman, C. Deeney, G. A. Chandler et al., Phys. Plasmas 5, 2105 (1997)] has enabled implosions of large diameter, high-wire-number arrays of titanium to begin testing Z pinch K-shell scaling theories. The 2 cm long titanium arrays, which were mounted on a 40 mm diameter, produced between 75+/-15 to 125+/-20 kJ of K-shell x rays. A mass scan indicates that, as predicted, higher velocity implosions in the series produced higher x-ray yields. Spectroscopic analyses indicate that these high velocity implosions achieved peak electron temperatures from 2.7+/-0.1 to 3.2+/-0.2 keV and obtained a K-shell emission mass participation of up to 12%. (C) 1999 American Institute of Physics. [S1070-664X(99)97105-7]. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. USN, Res Lab, Div Plasma Phys, Washington, DC 20375 USA. Univ London Imperial Coll Sci Technol & Med, Plasma Phys Grp, London, England. RP Deeney, C (reprint author), Sandia Natl Labs, MS-1194,POB 5800, Albuquerque, NM 87185 USA. NR 29 TC 62 Z9 63 U1 0 U2 4 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1999 VL 6 IS 5 BP 2081 EP 2088 DI 10.1063/1.873461 PN 2 PG 8 WC Physics, Fluids & Plasmas SC Physics GA 190ND UT WOS:000079969500050 ER PT J AU Tubbs, DL Barnes, CW Beck, JB Hoffman, NM Oertel, JA Watt, RG Boehly, T Bradley, D Jaanimagi, P Knauer, J AF Tubbs, DL Barnes, CW Beck, JB Hoffman, NM Oertel, JA Watt, RG Boehly, T Bradley, D Jaanimagi, P Knauer, J TI Cylindrical implosion experiments using laser direct drive SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 40th Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 16-20, 1998 CL NEW ORLEANS, LOUISIANA SP Amer Phys Soc, Div Plasma Phys ID RAYLEIGH-TAYLOR INSTABILITY; NATIONAL-IGNITION-FACILITY; GROWTH; SIMULATIONS; TARGETS; DESIGN AB Direct-drive cylindrical-implosion experiments are performed to study perturbed hydrodynamic flows in convergent geometry. Two experimental campaigns have been conducted, to demonstrate the advantages of direct over indirect drive and to validate numerical simulations of zeroth-order hydrodynamics and single-mode perturbation growth. Results and analysis of three unperturbed-target shots and two perturbed-target shots are discussed in detail. For unperturbed-target implosions, positions of inner and outer shell edges agree between simulation and experiment during the laser pulse. However, observed shell thickness is greater than simulated in unperturbed targets during deceleration and rebound; the effect appears only at the shell's exterior edge. For perturbed-target implosions, growth factors similar to 10-14 are observed, whereas growth factors near 30 are expected from simulation. Rayleigh-Taylor growth appears to differ between simulation and experiment. Observed zeroth-order flow at the exterior edge of imploding, perturbed targets appears to differ from simulation, even during acceleration. A possible physical model to explain such apparent differences is identified. (C) 1999 American Institute of Physics. [S1070-664X(99)96105-0]. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Rochester, Laser Energet Lab, Rochester, NY 14623 USA. RP Tubbs, DL (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 26 TC 25 Z9 28 U1 2 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1999 VL 6 IS 5 BP 2095 EP 2104 DI 10.1063/1.873462 PN 2 PG 10 WC Physics, Fluids & Plasmas SC Physics GA 190ND UT WOS:000079969500052 ER PT J AU Glenzer, SH Alley, WE Estabrook, KG De Groot, JS Haines, MG Hammer, JH Jadaud, JP MacGowan, BJ Moody, JD Rozmus, W Suter, LJ Weiland, TL Williams, EA AF Glenzer, SH Alley, WE Estabrook, KG De Groot, JS Haines, MG Hammer, JH Jadaud, JP MacGowan, BJ Moody, JD Rozmus, W Suter, LJ Weiland, TL Williams, EA TI Thomson scattering from laser plasmas SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 40th Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 16-20, 1998 CL NEW ORLEANS, LOUISIANA SP Amer Phys Soc, Div Plasma Phys ID INERTIAL-CONFINEMENT-FUSION; ION-ACOUSTIC-WAVES; STIMULATED RAMAN-SCATTERING; NATIONAL-IGNITION-FACILITY; HOHLRAUM PLASMAS; ELECTRON-TEMPERATURE; INDIRECTLY DRIVEN; LIGHT-SCATTERING; MAGNETIC-FIELDS; TRANSPORT AB Thomson scattering has recently been introduced as a fundamental diagnostic of plasma conditions and basic physical processes in dense, inertial confinement fusion plasmas. Experiments at the Nova laser facility [E. M. Campbell et al., Laser Part. Beams 9, 209 (1991)] have demonstrated accurate temporally and spatially resolved characterization of densities, electron temperatures, and average ionization levels by simultaneously observing Thomson scattered light from ion acoustic and electron plasma (Langmuir) fluctuations. In addition, observations of fast and slow ion acoustic waves in two-ion species plasmas have also allowed an independent measurement of the ion temperature. These results have motivated the application of Thomson scattering in closed-geometry inertial confinement fusion hohlraums to benchmark integrated radiation-hydrodynamic modeling of fusion plasmas. For this purpose a high energy 4 omega probe laser was implemented recently allowing ultraviolet Thomson scattering at various locations in high-density gas-filled hohlraum plasmas. In particular, the observation of steep electron temperature gradients indicates that electron thermal transport is inhibited in these gas-filled hohlraums. Hydrodynamic calculations which include an exact treatment of large-scale magnetic fields are in agreement with these findings. Moreover, the Thomson scattering data clearly indicate axial stagnation in these hohlraums by showing a fast rise of the ion temperature. Its timing is in good agreement with calculations indicating that the stagnating plasma will not deteriorate the implosion of the fusion capsules in ignition experiments. [S1070-664X(99)96305-X]. C1 Univ Calif Davis, Dept Appl Sci, Davis, CA 95616 USA. Univ Calif Davis, Plasma Res Grp, Davis, CA 95616 USA. Univ London Imperial Coll Sci Technol & Med, London SW7 2BZ, England. DAM Ile France, CEA, F-91680 Bruyeres Le Chatel, France. Univ Alberta, Dept Phys, Edmonton, AB T6G 2J1, Canada. Univ Calif Lawrence Livermore Natl Lab, Inst Laser Sci Applicat, Livermore, CA 94550 USA. RP Glenzer, SH (reprint author), Univ Calif Lawrence Livermore Natl Lab, L-399,POB 808, Livermore, CA 94551 USA. NR 76 TC 96 Z9 97 U1 2 U2 18 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1999 VL 6 IS 5 BP 2117 EP 2128 DI 10.1063/1.873499 PN 2 PG 12 WC Physics, Fluids & Plasmas SC Physics GA 190ND UT WOS:000079969500054 ER PT J AU Hammer, JH Tabak, M Wilks, SC Lindl, JD Bailey, DS Rambo, PW Toor, A Zimmerman, GB Porter, JL AF Hammer, JH Tabak, M Wilks, SC Lindl, JD Bailey, DS Rambo, PW Toor, A Zimmerman, GB Porter, JL TI High yield inertial confinement fusion target design for a z-pinch-driven hohlraum SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 40th Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 16-20, 1998 CL NEW ORLEANS, LOUISIANA SP Amer Phys Soc, Div Plasma Phys AB Calculations are presented for a high yield inertial fusion design, employing indirect drive with a double-ended z-pinch-driven hohlraum radiation source. A high current (similar to 60 MA) accelerator implodes z pinches within an enclosing hohlraum. Radial spoke arrays and shine shields isolate the capsule from the pinch plasma, magnetic field, and direct x-ray shine. Our approach places minimal requirements on z-pinch uniformity and stability, usually problematic due to magneto-Rayleigh-Taylor instability. Large inhomogeneities of the pinch and spoke array may be present, but the hohlraum adequately smooths the radiation field at the capsule. Simultaneity and reproducibility of the pinch x-ray output to better than 7% are required, however, for good symmetry. Recent experiments suggest a pulse shaping technique, through implosion of a multishell z pinch. X-ray bursts are calculated and observed to occur at each shell collision. A capsule absorbing 1 MJ of x rays at a peak drive temperature of 210 eV is found to have adequate stability and to produce 400 MJ of yield. A larger capsule absorbs 2 MJ with a yield of 1200 MJ. (C) 1999 American Institute of Physics. [S1070-664X(99)97605-X]. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Hammer, JH (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 14 TC 124 Z9 128 U1 0 U2 9 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1999 VL 6 IS 5 BP 2129 EP 2136 DI 10.1063/1.873464 PN 2 PG 8 WC Physics, Fluids & Plasmas SC Physics GA 190ND UT WOS:000079969500055 ER PT J AU Landen, OL Amendt, PA Suter, LJ Turner, RE Glendinning, SG Haan, SW Pollaine, SM Hammel, BA Tabak, M Rosen, MD Lindl, JD AF Landen, OL Amendt, PA Suter, LJ Turner, RE Glendinning, SG Haan, SW Pollaine, SM Hammel, BA Tabak, M Rosen, MD Lindl, JD TI A simple time-dependent analytic model of the P-2 asymmetry in cylindrical hohlraums SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 40th Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 16-20, 1998 CL NEW ORLEANS, LOUISIANA SP Amer Phys Soc, Div Plasma Phys ID INERTIAL CONFINEMENT FUSION; MULTIPLE-BEAM CONES; DRIVE LASER-FUSION; NOVA LASER; SYMMETRY EXPERIMENTS; OMEGA-LASER; TARGETS; SYSTEM; PERFORMANCE; IGNITION AB A simple time-dependent analytic view factor model for the P-2 asymmetry in cylindrical hohlraums is presented. The model includes the effects of hohlraum wall motion, time-varying hohlraum wall albedo and time-varying hohlraum-to-capsule diameter. The results of the model compare well with predictions from two-dimensional radiation hydrodynamics computer simulations and with time-resolved hohlraum symmetry data obtained at the Nova laser facility [J. T. Hunt and D. R. Speck, Opt. Eng. 28, 461 (1989)] and Omega laser facility [J. M. Sources, R. L. McCrory, C. P. Verdon et al., Phys. Plasmas 3, 2108 (1996)]. The model is also extended to the more complicated but relevant case of a multiple-ring cylindrical hohlraum illumination geometry, the baseline scheme for the National Ignition Facility [J. A. Paisner, J. D. Boyes, S. A. Kumpan, and M. Sorem, ICF Quart. 5, 110 (1995)]. (C) 1999 American Institute of Physics. [S1070-664X(99)94105-8]. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Landen, OL (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808, Livermore, CA 94550 USA. NR 28 TC 25 Z9 26 U1 1 U2 6 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1999 VL 6 IS 5 BP 2137 EP 2143 DI 10.1063/1.873465 PN 2 PG 7 WC Physics, Fluids & Plasmas SC Physics GA 190ND UT WOS:000079969500056 ER PT J AU Wharton, KB Kirkwood, RK Glenzer, SH Estabrook, KG Afeyan, BB Cohen, BI Moody, JD MacGowan, BJ Joshi, C AF Wharton, KB Kirkwood, RK Glenzer, SH Estabrook, KG Afeyan, BB Cohen, BI Moody, JD MacGowan, BJ Joshi, C TI Observation of resonant energy transfer between identical-frequency laser beams SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 40th Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 16-20, 1998 CL NEW ORLEANS, LOUISIANA SP Amer Phys Soc, Div Plasma Phys ID ION-ACOUSTIC-WAVES; STIMULATED RAMAN-SCATTERING; ELECTRON-PLASMA; POWER TRANSFER; BRILLOUIN; FILAMENTATION; GROWTH; LIGHT AB Enhanced transmission of a low intensity laser beam is observed when crossed with an identical-frequency beam in a plasma with a flow velocity near the ion sound speed. The time history of the enhancement and the dependence on the flow velocity strongly suggest that this is due to energy transfer between the beams via a resonant ion wave with zero frequency in the laboratory frame. The maximum energy transfer has been observed when the beams cross in a region with Mach 1 flow. The addition of frequency modulation on the crossing beams is seen to reduce the energy transfer by a factor of 2. Implications for indirect-drive fusion schemes are discussed. [S1070-664X(99)94205-2]. C1 Univ Calif Los Angeles, Los Angeles, CA 90024 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Polymath Associates, Livermore, CA 94550 USA. Univ Nevada, Reno, NV 89557 USA. RP Wharton, KB (reprint author), Univ Calif Los Angeles, Los Angeles, CA 90024 USA. NR 36 TC 17 Z9 17 U1 0 U2 6 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1999 VL 6 IS 5 BP 2144 EP 2149 DI 10.1063/1.873500 PN 2 PG 6 WC Physics, Fluids & Plasmas SC Physics GA 190ND UT WOS:000079969500057 ER PT J AU Dittrich, TR Haan, SW Marinak, MM Pollaine, SM Hinkel, DE Munro, DH Verdon, CP Strobel, GL McEachern, R Cook, RC Roberts, CC Wilson, DC Bradley, PA Foreman, LR Varnum, WS AF Dittrich, TR Haan, SW Marinak, MM Pollaine, SM Hinkel, DE Munro, DH Verdon, CP Strobel, GL McEachern, R Cook, RC Roberts, CC Wilson, DC Bradley, PA Foreman, LR Varnum, WS TI Review of indirect-drive ignition design options for the National Ignition Facility SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 40th Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 16-20, 1998 CL NEW ORLEANS, LOUISIANA SP Amer Phys Soc, Div Plasma Phys ID CAPSULE DESIGN; DEUTERIUM; STATE; EQUATION; TRITIUM AB Several inertial confinement fusion (ICF) capsule designs have been proposed as possible candidates for achieving ignition by indirect drive on the National Ignition Facility (NIF) laser [Paisner et al., Laser Focus World 30, 75 (1994)]. This article reviews these designs, their predicted performance using one-, two-, and three- dimensional numerical simulations, and their fabricability. Recent design work at a peak x-ray drive temperature of 250 eV with either 900 or 1300 kJ total laser energy confirms earlier capsule performance estimates [Lindl, Phys. Plasmas 2, 3933 (1995)] that were based on hydrodynamic stability arguments. These simulations at 250 eV and others at the nominal 300 eV drive show that capsules having either copper doped beryllium (Be+Cu) or polyimide (C22H10N2O4) ablators have favorable implosion stability and material fabrication properties. Prototypes of capsules using these ablator materials are being constructed using several techniques: brazing together machined hemishells (Be+Cu), sputter deposition (Be+Cu), and monomer deposition followed by thermal processing (polyimide). [S1070-664X(99)95305-3]. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Dittrich, TR (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 30 TC 104 Z9 105 U1 6 U2 22 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1999 VL 6 IS 5 BP 2164 EP 2170 DI 10.1063/1.873467 PN 2 PG 7 WC Physics, Fluids & Plasmas SC Physics GA 190ND UT WOS:000079969500060 ER PT J AU Hoarty, D Willi, O Barringer, L Vickers, C Watt, R Nazarov, W AF Hoarty, D Willi, O Barringer, L Vickers, C Watt, R Nazarov, W TI Observation of ionization fronts in low density foam targets SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 40th Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 16-20, 1998 CL NEW ORLEANS, LOUISIANA SP Amer Phys Soc, Div Plasma Phys ID INERTIAL CONFINEMENT FUSION; LASER FACILITY; RADIATION; DRIVEN; PLASMAS AB Ionization fronts have been observed in low density chlorinated foam targets and low density foams confined in gold tubes using time resolved K-shell absorption spectroscopy. The front was driven by an intense pulse of soft x-rays produced by high power laser irradiation. The density and temperature profiles inferred from the radiographs provided detailed measurement of the conditions. The experimental data were compared to radiation hydrodynamics simulations and reasonable agreement was obtained. (C) 1999 American Institute of Physics. [S1070-664X(99)95605-7]. C1 Univ London Imperial Coll Sci Technol & Med, London, England. AWE Aldermaston, Dept Radiat Phys, Reading, Berks, England. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Dundee, Dept Chem, Dundee DD1 4HN, Scotland. RP Hoarty, D (reprint author), Univ London Imperial Coll Sci Technol & Med, London, England. NR 23 TC 37 Z9 47 U1 1 U2 5 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1999 VL 6 IS 5 BP 2171 EP 2177 DI 10.1063/1.873468 PN 2 PG 7 WC Physics, Fluids & Plasmas SC Physics GA 190ND UT WOS:000079969500061 ER PT J AU Peterson, DL Bowers, RL Matuska, W McLenithan, KD Chandler, GA Deeney, C Derzon, MS Douglas, M Matzen, MK Nash, TJ Spielman, RB Struve, KW Stygar, WA Roderick, NF AF Peterson, DL Bowers, RL Matuska, W McLenithan, KD Chandler, GA Deeney, C Derzon, MS Douglas, M Matzen, MK Nash, TJ Spielman, RB Struve, KW Stygar, WA Roderick, NF TI Insights and applications of two-dimensional simulations to Z-pinch experiments SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 40th Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 16-20, 1998 CL NEW ORLEANS, LA SP Amer Phys Soc, Div Plasma Phys AB A two-dimensional (2D) Eulerian radiation-magnetohydrodynamic code has been used to successfully simulate hollow metallic z-pinch experiments fielded on several facilities with a wide variety of drive conditions, time scales, and loads. The 2D simulations of these experiments reproduce important quantities of interest including the radiation pulse energy, power, and pulse width. This match is obtained through the use of an initial condition: the amplitude of a random density perturbation imposed on the initial plasma shell. The perturbations seed the development of magnetically driven Rayleigh-Taylor instabilities which greatly affect the dynamics of the implosion and the resulting production of radiation. Analysis of such simulations allows insights into the physical processes by which these calculations reproduce the experimental results. As examples, the insights gained from the simulations of Sandia "Z'' accelerator [R. B. Spielman et al., Phys. Plasmas 5, 2105 (1998)] experiments have allowed for the investigation of possible physical processes which produce high powers in "nested array'' implosions and high temperatures within "dynamic hohlraum'' loads. Building on these insights, the 2D code has been used in designing new experiments to optimize the desired physical conditions and in interpreting the experimental results obtained. These examples and others will be discussed as well as examples of simulation results where improvement is needed and what steps are being taken to make that improvement. (C) 1999 American Institute of Physics. [S1070-664X(99)93805-3]. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. Univ New Mexico, Albuquerque, NM 87131 USA. RP Peterson, DL (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 12 TC 81 Z9 82 U1 0 U2 3 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1999 VL 6 IS 5 BP 2178 EP 2184 DI 10.1063/1.873469 PN 2 PG 7 WC Physics, Fluids & Plasmas SC Physics GA 190ND UT WOS:000079969500062 ER PT J AU Haber, I Friedman, A Grote, DP Lund, SM Kishek, RA AF Haber, I Friedman, A Grote, DP Lund, SM Kishek, RA TI Recent progress in the simulation of heavy ion beams SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 40th Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 16-20, 1998 CL NEW ORLEANS, LOUISIANA SP Amer Phys Soc, Div Plasma Phys ID PARTICLE BEAMS; TRANSPORT; EMITTANCE; ENERGY; LBNL AB Production of electric power by using a beam of heavy ions to ignite an inertially-confined fusion target requires the focusing of high-power beams onto a small spot several meters distant from the final lens system. Beams with the necessary intensity generally behave like warm nonneutral bounded plasmas where beam kinetic temperatures are sufficiently high that a cold-plasma description can be inadequate for describing the collective space-charge modes. In view of the complexity of the self-consistent nonlinear dynamics, analytic study has largely been limited to the singular Kapchinskij-Vladimirskij (K-V) distribution. Numerical simulations, primarily using the WARP [D. P. Grote, A. Friedman, I. Haber, W. Fawley, and J. L. Vay, Nucl. Instrum. Methods Phys. Res. A 415, 428 (1998)] particle-in-cell (PIC)/accelerator code, have been employed to identify the degree to which the analytic results, especially the predictions of unstable modes, are applicable to realistic beam distributions. During extensive benchmarking of the code against experiments at Lawrence Berkeley National Laboratory, Lawrence Livermore National Laboratory, and the University of Maryland, a particular feature of the beam which has been seen in both experiment and simulation is the launching, in the source region, of collective warm-plasma oscillations similar to those predicted on the basis of the K-V analysis. (C) 1999 American Institute of Physics. [S1070-664X(99)96605-3]. C1 USN, Res Lab, Div Plasma Phys, Washington, DC 20375 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Maryland, Inst Plasma Res, College Pk, MD 20742 USA. RP Haber, I (reprint author), USN, Res Lab, Div Plasma Phys, Washington, DC 20375 USA. NR 33 TC 24 Z9 23 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1999 VL 6 IS 5 BP 2254 EP 2261 DI 10.1063/1.873477 PN 2 PG 8 WC Physics, Fluids & Plasmas SC Physics GA 190ND UT WOS:000079969500071 ER PT J AU Esarey, E Schroeder, CB Leemans, WP Hafizi, B AF Esarey, E Schroeder, CB Leemans, WP Hafizi, B TI Laser-induced electron trapping in plasma-based accelerators SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 40th Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 16-20, 1998 CL NEW ORLEANS, LOUISIANA SP Amer Phys Soc, Div Plasma Phys ID RAMAN-SCATTERING; WAVE-BREAKING; PULSES; WAKEFIELD; INJECTION; DRIVEN; EXCITATION; GENERATION; AMPLITUDE; BEAMS AB Trapping of plasma electrons in the self-modulated laser wakefield accelerator (LWFA) via the coupling of Raman backscatter to the wake is examined analytically and with three-dimensional (3-D) test particle simulations. The trapping threshold for linear polarization is much less than for circular and occurs for wake amplitudes of delta n/n similar to 25%, which is well below wave breaking. Self-channeling provides continuous focusing of the accelerated electrons which, along with relativistic pump laser effects, can enhance the energy gain by a factor greater than or equal to 2. The colliding pulse method for injecting electrons in the standard LWFA is examined. Simulations of test electrons in 3-D fields indicate the production of relativistic (greater than or equal to 25 MeV) high-quality electron bunches with ultrashort durations (a few femtoseconds), small energy spreads (a few percent), and low normalized emittances (1 mm mrad). (C) 1999 American Institute of Physics. [S1070-664X(99)96705-8]. C1 Univ Calif Berkeley, Ernest Orlando Lawrence Berkeley Natl Lab, Ctr Beam Phys, Berkeley, CA 94720 USA. Icarus Res Inc, Bethesda, MD 20824 USA. RP Esarey, E (reprint author), Univ Calif Berkeley, Ernest Orlando Lawrence Berkeley Natl Lab, Ctr Beam Phys, Berkeley, CA 94720 USA. OI Schroeder, Carl/0000-0002-9610-0166 NR 33 TC 48 Z9 50 U1 2 U2 7 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1999 VL 6 IS 5 BP 2262 EP 2268 DI 10.1063/1.873478 PN 2 PG 7 WC Physics, Fluids & Plasmas SC Physics GA 190ND UT WOS:000079969500072 ER PT J AU Volfbeyn, P Esarey, E Leemans, WP AF Volfbeyn, P Esarey, E Leemans, WP TI Guiding of laser pulses in plasma channels created by the ignitor-heater technique SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 40th Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 16-20, 1998 CL NEW ORLEANS, LOUISIANA SP Amer Phys Soc, Div Plasma Phys ID WAVE-GUIDE; PREFORMED PLASMA; WAKEFIELD EXCITATION; UNDERDENSE PLASMA; GASES; SIMULATIONS; ACCELERATOR; IONIZATION; GENERATION; MODULATION AB Experimental and theoretical investigations of laser guiding in plasma channels are reported. Intense (<5 X 10(17) W/cm(2)), short (75 fs) laser pulses have been injected and guided in channels produced using a novel ignitor-heater technique, which uses two laser pulses. The ignitor, an ultrashort (<100 fs) laser pulse, is brought to a line focus to ionize the gas jet. The heater pulse (160 ps long) is subsequently used to heat the existing spark via inverse Bremsstrahlung. The hydrodynamic shock expansion creates a channel. This technique allows the creation of slab or cylindrical channels in low atomic number gases, e. g., hydrogen. The channel profile was diagnosed with time resolved longitudinal interferometry. The effects of laser beam size and divergence mismatch at the channel entrance and leakage of the laser energy out of the channel are studied theoretically and experimentally in one and two transverse dimensions. An all-optical channel wake diagnostic based on Fourier domain interferometry is discussed, and a holographic-type inversion technique is proposed to increase the accuracy and reach of this method. [S1070-664X(99)97205-1]. C1 Univ Calif Berkeley, Ernest Orlando Lawrence Berkeley Natl Lab, Ctr Beam Phys, Berkeley, CA 94720 USA. RP Volfbeyn, P (reprint author), Univ Calif Berkeley, Ernest Orlando Lawrence Berkeley Natl Lab, Ctr Beam Phys, Berkeley, CA 94720 USA. NR 41 TC 132 Z9 133 U1 0 U2 12 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1999 VL 6 IS 5 BP 2269 EP 2277 DI 10.1063/1.873503 PN 2 PG 9 WC Physics, Fluids & Plasmas SC Physics GA 190ND UT WOS:000079969500073 ER PT J AU Savchenko, VI Fisch, NJ Starostin, AN Panteleev, AA AF Savchenko, VI Fisch, NJ Starostin, AN Panteleev, AA TI Unusual radiation effects from atoms in gases and plasmas SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 40th Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 16-20, 1998 CL NEW ORLEANS, LOUISIANA SP Amer Phys Soc, Div Plasma Phys ID SPONTANEOUS EMISSION CANCELLATION; INTERFERENCE; INVERSION AB New interesting effects arise, when three-level atoms interact with the plasma, laser field, or a heat bath. If the atoms inside the plasma are excited by the polarized laser pulse or an electron beam, the line wings of the radiation are completely polarized, while the line core is only partially polarized. The Einstein coefficients are generalized to the case, when the atomic decay channels are subject to quantum interference. Such atoms may develop nonzero quantum coherence between upper levels, if they are in contact with the heat bath in thermal equilibrium. This coherency changes the emissivity of the medium and hence can be experimentally observed. In the case when three-level atoms interact with the laser field, spontaneous emission can be suppressed over the whole frequency spectrum. (C) 1999 American Institute of Physics. [S1070-664X(99)93105-1]. C1 Princeton Univ, Plasma Phys Lab, Princeton, NJ 08543 USA. TRINITI, Moscow, Russia. Moscow Inst Phys & Technol, Moscow, Russia. RP Savchenko, VI (reprint author), Princeton Univ, Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 18 TC 0 Z9 0 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1999 VL 6 IS 5 BP 2278 EP 2283 DI 10.1063/1.873479 PN 2 PG 6 WC Physics, Fluids & Plasmas SC Physics GA 190ND UT WOS:000079969500074 ER PT J AU Herrmann, HW Henins, I Park, J Selwyn, GS AF Herrmann, HW Henins, I Park, J Selwyn, GS TI Decontamination of chemical and biological warfare, (CBW) agents using an atmospheric pressure plasma jet (APPJ) SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 40th Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 16-20, 1998 CL NEW ORLEANS, LOUISIANA SP Amer Phys Soc, Div Plasma Phys ID STERILIZATION AB The atmospheric pressure plasma jet (APPJ) [A. Schutze et al., IEEE Trans. Plasma Sci. 26, 1685 (1998)] is a nonthermal, high pressure, uniform glow plasma discharge that produces a high velocity effluent stream of highly reactive chemical species. The discharge operates on a feedstock gas (e.g., He/O-2/H2O), which flows between an outer, grounded, cylindrical electrode and an inner, coaxial electrode powered at 13.56 MHz rf. While passing through the plasma, the feedgas becomes excited, dissociated or ionized by electron impact. Once the gas exits the discharge volume, ions and electrons are rapidly lost by recombination, but the fast-flowing effluent still contains neutral metastable species (e.g., O-2*, He*) and radicals (e. g., O, OH). This reactive effluent has been shown to be an effective neutralizer of surrogates for anthrax spores and mustard blister agent. Unlike conventional wet decontamination methods, the plasma effluent does not cause corrosion and it does not destroy wiring, electronics, or most plastics, making it highly suitable for decontamination of sensitive equipment and interior spaces. Furthermore, the reactive species in the effluent rapidly degrade into harmless products leaving no lingering residue or harmful by-products. (C) 1999 American Institute of Physics. [S1070-664X(99)91405-2]. C1 Univ Calif Los Alamos Natl Lab, Div Phys, Los Alamos, NM 87545 USA. RP Herrmann, HW (reprint author), Univ Calif Los Alamos Natl Lab, Div Phys, Los Alamos, NM 87545 USA. NR 16 TC 225 Z9 243 U1 8 U2 44 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1999 VL 6 IS 5 BP 2284 EP 2289 DI 10.1063/1.873480 PN 2 PG 6 WC Physics, Fluids & Plasmas SC Physics GA 190ND UT WOS:000079969500075 ER PT J AU Choueiri, EY AF Choueiri, EY TI Anomalous resistivity and heating in current-driven plasma thrusters SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 40th Annual Meeting of the Division of Plasma Physics of the American-Physical-Society CY NOV 16-20, 1998 CL NEW ORLEANS, LA SP Amer Phys Soc, Div Plasma Phys ID FIELD STREAMING INSTABILITY; MAGNETOPLASMADYNAMIC THRUSTERS; MAGNETIC-FIELD; DRIFT AB A theory is presented of anomalous resistivity and particle heating in current-driven plasma accelerators such as the magnetoplasmadynamic thruster (MPDT). An electromagnetic dielectric tensor is used for a current-carrying, collisional and finite-beta plasma and it is found that an instability akin to the generalized lower hybrid drift instability (GLHDI) exists for electromagnetic modes (i.e., with finite polarization). Weak turbulence theory is then used to develop a second-order description of the heating rates of particles by the waves and the electron-wave momentum exchange rate that controls the anomalous resistivity effect. It is found that the electron Hall parameter strongly scales the level of anomalous dissipation for the case of the MPDT plasma. This scaling has recently been confirmed experimentally [Phys. Plasmas 5, 3581 (1997)]. Polynomial expressions of the relevant transport coefficients cast solely in terms of macroscopic parameters are also obtained for including microturbulence effects in numerical plasma fluid models used for thruster flow simulation. (C) 1999 American Institute of Physics. [S1070-664X(99)95705-1]. C1 Princeton Univ, Elect Propuls & Plasma Dynam Lab, Princeton, NJ 08544 USA. RP Princeton Univ, Elect Propuls & Plasma Dynam Lab, Princeton, NJ 08544 USA. NR 40 TC 22 Z9 22 U1 0 U2 1 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 1070-664X EI 1089-7674 J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1999 VL 6 IS 5 BP 2290 EP 2306 DI 10.1063/1.873481 PN 2 PG 17 WC Physics, Fluids & Plasmas SC Physics GA 190ND UT WOS:000079969500076 ER PT J AU Dreicer, H AF Dreicer, H TI John Marshall Jr - Obituary SO PHYSICS TODAY LA English DT Biographical-Item C1 Los Alamos Natl Lab, Los Alamos, NM 87544 USA. RP Dreicer, H (reprint author), Los Alamos Natl Lab, Los Alamos, NM 87544 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0031-9228 J9 PHYS TODAY JI Phys. Today PD MAY PY 1999 VL 52 IS 5 BP 90 EP 91 DI 10.1063/1.882675 PG 2 WC Physics, Multidisciplinary SC Physics GA 192JU UT WOS:000080075900020 ER PT J AU Hughes, R Nordholt, J AF Hughes, R Nordholt, J TI Quantum cryptography takes to the air SO PHYSICS WORLD LA English DT Article C1 Univ Calif Los Alamos Natl Lab, Div Phys, Los Alamos, NM 87545 USA. RP Hughes, R (reprint author), Univ Calif Los Alamos Natl Lab, Div Phys, Los Alamos, NM 87545 USA. NR 5 TC 5 Z9 5 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0953-8585 J9 PHYS WORLD JI Phys. World PD MAY PY 1999 VL 12 IS 5 BP 31 EP 35 PG 5 WC Physics, Multidisciplinary SC Physics GA 195AX UT WOS:000080227900028 ER PT J AU Quinn, H Hewett, J AF Quinn, H Hewett, J TI CP and T violations: new results leave open questions SO PHYSICS WORLD LA English DT Article C1 Stanford Linear Accelerator Ctr, Theoret Particle Phys Grp, Stanford, CA 94309 USA. RP Quinn, H (reprint author), Stanford Linear Accelerator Ctr, Theoret Particle Phys Grp, POB 4349, Stanford, CA 94309 USA. NR 8 TC 1 Z9 1 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0953-8585 J9 PHYS WORLD JI Phys. World PD MAY PY 1999 VL 12 IS 5 BP 37 EP 42 PG 6 WC Physics, Multidisciplinary SC Physics GA 195AX UT WOS:000080227900029 ER PT J AU Van Tuinen, A Peters, AHLJ Kendrick, RE Zeevaart, JAD Koornneef, M AF Van Tuinen, A Peters, AHLJ Kendrick, RE Zeevaart, JAD Koornneef, M TI Characterisation of the procera mutant of tomato and the interaction of gibberellins with end-of-day far-red light treatments SO PHYSIOLOGIA PLANTARUM LA English DT Article ID SIGNAL-TRANSDUCTION; INTERNODE LENGTH; PRO-GENE; ARABIDOPSIS-THALIANA; INSENSITIVE MUTANT; PISUM GIBBERELLINS; DEFICIENT MUTANTS; PHYTOCHROME; RESPONSES; REGULATOR AB The tomato (Solanum lycopersicum L.) slender mutant procera (pro)) was analysed for its relationship with gibberellin (GA) by combining it with GA deficiency due to the gib-1 mutation, The sensitivity to GA biosynthesis inhibitors and the GA content were measured in the pro gib-1 double mutant. In the gib-1 mutant background, the pro mutation strongly reduced the GA requirement for seed germination and stem growth and almost fully restored the morphological leaf defects of the gib-1 mutant. An end-of-day far-red light treatment, when applied to the various genotypes, indicated that GAs are required for a response to this treatment, but that it act independently of the Pro gene product. C1 Agr Univ Wageningen, Genet Lab, NL-6703 HA Wageningen, Netherlands. INRA, Biol Cellulaire Lab, F-78026 Versailles, France. Agr Univ Wageningen, Lab Plant Physiol, NL-6703 BD Wageningen, Netherlands. Michigan State Univ, DOE, Plant Res Lab, E Lansing, MI 48824 USA. RP Koornneef, M (reprint author), Agr Univ Wageningen, Genet Lab, Dreijenlaan 2, NL-6703 HA Wageningen, Netherlands. OI Koornneef, Maarten/0000-0002-7759-4869 NR 37 TC 21 Z9 22 U1 3 U2 11 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 MAY PY 1999 VL 106 IS 1 BP 121 EP 128 DI 10.1034/j.1399-3054.1999.106117.x PG 8 WC Plant Sciences SC Plant Sciences GA 209YF UT WOS:000081077000017 ER PT J AU Ellsworth, DS AF Ellsworth, DS TI CO2 enrichment in a maturing pine forest: are CO2 exchange and water status in the canopy affected? SO PLANT CELL AND ENVIRONMENT LA English DT Article DE Pinus taeda L.; CO2 assimilation; drought; elevated CO2; free-air CO2 enrichment; loblolly pine photosynthesis; pine forest canopy; stable carbon isotopes; stomata; water stress ID LEAF GAS-EXCHANGE; INCREASING ATMOSPHERIC CO2; ELEVATED CARBON-DIOXIDE; STOMATAL CONDUCTANCE; LOBLOLLY-PINE; NET PHOTOSYNTHESIS; RESPONSES; SEEDLINGS; DROUGHT; GROWTH AB Elevated CO2 is expected to reduce forest water use as a result of CO2-induced stomatal closure, which has implications for ecosystem-scale phenomena controlled by water availability. Leaf-level CO2 and H2O exchange responses and plant and soil water relations were examined in a maturing loblolly pine (Pinus taeda L,) stand in a free-air CO2 enrichment (FACE) experiment in North Carolina, USA to test if these parameters were affected by elevated CO2, Current-year foliage in the canopy was continuously exposed to elevated CO2 (ambient CO2 + 200 mu mol mol(-1)) in free-air during needle growth and development for lip to 400 d. Photosynthesis in upper canopy foliage was stimulated by 50-60% by elevated CO2 compared with ambient controls. This enhancement was similar in current-year, ambient-grown foliage temporarily measured at elevated CO2 compared with long-term elevated CO2 grown foliage, Significant photosynthetic enhancement by CO2 was maintained over a range of conditions except during peak drought. There was no evidence of water savings in elevated CO2 plots in FACE compared to ambient plots under drought and non-drought conditions. This was supported by evidence from three independent measures. First, stomatal conductance was not significantly different in elevated CO2 versus ambient trees of P. taeda, Calculations of time-integrated c(i)/c(a) ratios from analysis of foliar delta(13)C showed that these ratios were maintained in foliage under elevated CO2. Second, soil moisture was not significantly different between ambient and elevated CO2 plots during drought. Third, pre-dawn and mid-day leaf water potentials were also unaffected by the seasonal CO2 exposure, as were tissue osmotic potentials and turgor loss points. Together the results strongly support the hypothesis that maturing P. taeda trees have low stomatal responsiveness to elevated CO2. Elevated CO2 effects on water relations in loblolly pine-dominated forest ecosystems may be absent or small apart from those mediated by leaf area. Large photosynthetic enhancements in the upper canopy of P. taeda by elevated CO2 indicate that this maturing forest may have a large carbon sequestration capacity with limiting water supply. C1 Brookhaven Natl Lab, Environm Biol & Instrumentat Div, Upton, NY 11973 USA. RP Ellsworth, DS (reprint author), Brookhaven Natl Lab, Environm Biol & Instrumentat Div, Upton, NY 11973 USA. OI Ellsworth, David/0000-0002-9699-2272 NR 56 TC 178 Z9 190 U1 4 U2 27 PU BLACKWELL SCIENCE LTD PI OXFORD PA P O BOX 88, OSNEY MEAD, OXFORD OX2 0NE, OXON, ENGLAND SN 0140-7791 J9 PLANT CELL ENVIRON JI Plant Cell Environ. PD MAY PY 1999 VL 22 IS 5 BP 461 EP 472 DI 10.1046/j.1365-3040.1999.00433.x PG 12 WC Plant Sciences SC Plant Sciences GA 217VU UT WOS:000081520300003 ER PT J AU McClements, KG Gryaznevich, MP Sharapov, SE Akers, RJ Appel, LC Counsell, GF Roach, CM Majeski, R AF McClements, KG Gryaznevich, MP Sharapov, SE Akers, RJ Appel, LC Counsell, GF Roach, CM Majeski, R TI Physics of energetic particle-driven instabilities in the START spherical tokamak SO PLASMA PHYSICS AND CONTROLLED FUSION LA English DT Article ID TOROIDAL ALFVEN EIGENMODES; INTERNAL KINK; DIII-D; EXCITATION; PLASMAS; WAVES; BETA; MODES; IONS AB The recent use of neutral beam injection (NBI) in the UKAEA small tight aspect ratio tokamak (START) has provided the first opportunity to study experimentally the physics of energetic ions in spherical tokamak (ST) plasmas. In such devices the ratio of major radius to minor radius R-0/a is of order unity. Several distinct classes of NBI-driven instability have been observed at frequencies up to 1 MHz during START discharges. These observations are described, and possible interpretations are given. Equilibrium data, corresponding to times of beam-driven wave activity, are used to compute continuous shear Alfven spectra: toroidicity and high plasma beta give rise to wide spectral gaps; extending up to frequencies of several times the Alfven gap frequency. In each of these gaps Alfvenic instabilities could, in principle, be driven by energetic ions. Chirping modes observed at high beta in this frequency range have bandwidths comparable to or greater than the gap widths. Instability drive in START is provided by beam ion pressure gradients (as in conventional tokamaks), and also by positive gradients in beam ion velocity distributions, which arise from velocity-dependent charge exchange losses. It is shown that fishbone-like bursts observed at a few tens of kHz can be attributed to internal kink mode excitation by passing beam ions, while narrowband emission at several hundred kHz may be due to excitation of fast Alfven (magnetosonic) eigenmodes. In the light of our understanding of energetic particle-driven instabilities in START, the possible existence of such instabilities in larger STs is discussed. C1 UKAEA Euratom Fus Assoc, Culham Sci Ctr, Abingdon OX14 3DB, Oxon, England. Jet Joint Undertaking, Abingdon OX14 3EA, Oxon, England. Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP McClements, KG (reprint author), UKAEA Euratom Fus Assoc, Culham Sci Ctr, Abingdon OX14 3DB, Oxon, England. NR 36 TC 38 Z9 38 U1 0 U2 3 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0741-3335 J9 PLASMA PHYS CONTR F JI Plasma Phys. Control. Fusion PD MAY PY 1999 VL 41 IS 5 BP 661 EP 678 DI 10.1088/0741-3335/41/5/307 PG 18 WC Physics, Fluids & Plasmas SC Physics GA 205CD UT WOS:000080803000007 ER PT J AU Lee, EC Muller, SJ AF Lee, EC Muller, SJ TI Flow light scattering studies of polymer coil conformation in solutions under shear: effect of solvent quality SO POLYMER LA English DT Article DE dilute polymer solution; light scattering; solvent quality ID MOLECULAR-ORIENTATION; ELONGATIONAL FLOW; DILUTE-SOLUTIONS; BIREFRINGENCE; POLYSTYRENE; DYNAMICS AB The orientation and deformation of polymer chains, in dilute solutions undergoing circular Couette flow, were measured by flow light scattering (FLS) techniques. Analysis of the angular dissymmetry of the scattered light intensity allowed the determination of polymer chain alignment in the flow direction, as well as a direct measurement of chain dimensions. The polymers were dissolved in several different solvents to determine the effect of solvent quality on polymer coil conformation under shear. The polymer solutions all consisted of a nearly monodisperse polystyrene sample of 3 x 10(6) g/mol molecular weight dissolved in various viscous solvents, including tricresyl phosphate, dioctyl phthalate, and a mixed solvent of low molecular weight polystyrene (M-w = 5780 g/mol) and dioctyl phthalate. There was a pronounced dependence of chain conformation on the quality of the solvent, with poorer solvents allowing more orientation of the polymers with the flow direction, as well as larger relative deformations. (C) 1999 Elsevier Science Ltd. All rights reserved. C1 Univ Calif Berkeley, Dept Chem Engn, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Adv Mat, Berkeley, CA 94720 USA. RP Muller, SJ (reprint author), Univ Calif Berkeley, Dept Chem Engn, Berkeley, CA 94720 USA. NR 29 TC 15 Z9 15 U1 1 U2 3 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0032-3861 J9 POLYMER JI Polymer PD MAY PY 1999 VL 40 IS 10 BP 2501 EP 2510 DI 10.1016/S0032-3861(98)00471-6 PG 10 WC Polymer Science SC Polymer Science GA 161LP UT WOS:000078290700005 ER PT J AU Tan, NCB Balogh, L Trevino, SF Tomalia, DA Lin, JS AF Tan, NCB Balogh, L Trevino, SF Tomalia, DA Lin, JS TI A small angle scattering study of dendrimer-copper sulfide nanocomposites SO POLYMER LA English DT Article DE dendrimers; nanocomposites; SANS ID STARBURST DENDRIMERS; CASCADE POLYMERS; CHEMISTRY AB Dendrimers are a new class of three-dimensional, man-made molecules produced by an unusual synthetic route which incorporates repetitive branching sequences to create a unique novel architecture. Exceptional features of the dendritic architecture include a high degree of structural symmetry, a density gradient displaying an intra-molecular minimum value and a well defined number of terminal groups which may be chemically different from the interior. The combination of these features creates an environment within the dendrimer molecule which facilitates trapping of guest species. Recently, dendritic polymers have been used as soluble templates/unimolecular reactors from which nano-clusters of inorganic compounds or elements can be synthesized. The basic concept involves using dendrimers as hosts to preorganize small molecules or metal ions, followed by a simple in situ reaction which will immobilize and stabilize domains of atomic or molecular guest components (inorganic compounds as well as elemental metals). In one of these examples poly(amidoamine) (PAMAM) dendrimers have been used, to attract copper(II) ions inside the macromolecules where they are subsequently reacted with solubilized H2S to form metal sulfides. These organic/inorganic, dendrimer-based hybrid species have been termed 'nanocomposites' and display unusual properties. For example, solubility of the nanocomposites is determined by the properties of the host dendrimer molecules. This allows for solubilization of the inorganic guest compounds in environments in which they are inherently insoluble. Since it has been established that there is no covalent bond between host and guest, these observations suggest that the inorganics are physically and spatially restricted by the dendrimer shell. However, this structure has not been verified. In this investigation a preliminary understanding of the physical structure of these dendrimer-based nanocomposites was sought. A model system of PAMAM dendrimer-copper sulfide nanocomposites was studied in various stages of its formation using a combination of small angle X-ray and neutron scattering experiments. The results suggest that little perturbation of the dendritic species occurs on complexation, but indicate that a secondary super-molecular aggregation phenomena occurs within nanocomposite solutions. (C) 1999 Published by Elsevier Science Ltd. All rights reserved. C1 USA, Res Lab, AMSRL WM MA, APG, Aberdeen, MD 21005 USA. Michigan Mol Inst, Midland, MI 48640 USA. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Oak Ridge Natl Labs, Oak Ridge, TN 37831 USA. RP Tan, NCB (reprint author), USA, Res Lab, AMSRL WM MA, APG, Bldg 4600, Aberdeen, MD 21005 USA. OI Balogh, Lajos/0000-0002-3115-0787 NR 30 TC 47 Z9 49 U1 0 U2 11 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0032-3861 J9 POLYMER JI Polymer PD MAY PY 1999 VL 40 IS 10 BP 2537 EP 2545 DI 10.1016/S0032-3861(98)00491-1 PG 9 WC Polymer Science SC Polymer Science GA 161LP UT WOS:000078290700008 ER PT J AU Fodor, JS Briber, RM Russell, TP Carter, KR Hedrick, JL Miller, RD Wong, A AF Fodor, JS Briber, RM Russell, TP Carter, KR Hedrick, JL Miller, RD Wong, A TI Non-uniform composition profiles in thin film polymeric nanofoams SO POLYMER LA English DT Article DE non-uniform composition profiles; thin films; polymeric nanofoams ID X-RAY-SCATTERING; PYROMELLITIC DIANHYDRIDE; POLYIMIDE NANOFOAMS; AROMATIC POLYIMIDE; FOAMS; COPOLYMERS; SURFACES AB Neutron reflectivity (NR) and dynamic secondary ion mass spectroscopy (DSIMS) were used to study compositional variations as a function of film depth in thin polymeric nanofoam films formed from triblock copolymers containing 15 wt%, 13 kg/mol polypropylene oxide end blocks with a fluorinated polyimide center block. The triblock copolymer films were spun cast and imidized on silicon substrates and showed an excess amount of polyimide present at both the air/film and film/substrate interfaces. Upon foaming the films showed a slight densification, and the formation of a 50-150 Angstrom thick polyimide skin at the air interface. The final nanofoam materials had a calculated porosity of roughly 20 vol.% in the center portion of the film. (C) 1999 Elsevier Science Ltd. All rights reserved. C1 Univ Maryland, Dept Mat & Nucl Engn, College Pk, MD 20742 USA. IBM Corp, Div Res, Almaden Res Ctr, San Jose, CA 95120 USA. Argonne Natl Lab, Intense Pulsed Neutron Source, Argonne, IL 60439 USA. RP Briber, RM (reprint author), Univ Maryland, Dept Mat & Nucl Engn, 2100 Marie Mount Hall, College Pk, MD 20742 USA. RI Briber, Robert/A-3588-2012; Carter, Kenneth/G-2594-2015 OI Briber, Robert/0000-0002-8358-5942; Carter, Kenneth/0000-0002-7081-2296 NR 31 TC 6 Z9 7 U1 1 U2 6 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0032-3861 J9 POLYMER JI Polymer PD MAY PY 1999 VL 40 IS 10 BP 2547 EP 2553 DI 10.1016/S0032-3861(98)00487-X PG 7 WC Polymer Science SC Polymer Science GA 161LP UT WOS:000078290700009 ER PT J AU Agarwal, A Dahotre, NB Allard, LF AF Agarwal, A Dahotre, NB Allard, LF TI Ceramic metal interface in laser deposited hard refractory composite coating: Electron microscopic study SO PRAKTISCHE METALLOGRAPHIE-PRACTICAL METALLOGRAPHY LA English DT Article AB Ceramic-metal interface plays the prime role in estimation of properties of composite and similar materials. In the present study, TiB2 has been deposited on AISI 1010 steel using laser surface engineering (LSE) process. TiB2/Fe interface is examined by electron microscopy (SEM and TEM) at microstructural and atomic level. A continuous, crack free and metallurgically bonded coating is obtained which is "composite" in nature. TiB2 particles are randomly distributed in Fe matrix without any preferred crystallographic orientation. High resolution transmission electron microscopy (HRTEM) shows that TiB2/Fe interface is atomically smooth and sharp with very little mismatch. There is no evidence of cracking or delamination at the interface. However, a small reaction zone of approximately 100 nm is formed at the interface as a consequence of non-equilibrium synthesis during LSE process. C1 Univ Tennessee, Inst Space, Dept Mat Sci & Engn, Ctr Laser Applicat, Tullahoma, TN 37388 USA. Oak Ridge Natl Lab, Div Met & Ceram, High Temp Mat Lab, Oak Ridge, TN 37831 USA. RP Agarwal, A (reprint author), Univ Tennessee, Inst Space, Dept Mat Sci & Engn, Ctr Laser Applicat, Tullahoma, TN 37388 USA. NR 13 TC 7 Z9 7 U1 0 U2 1 PU CARL HANSER VERLAG PI MUNICH PA KOLBERGERSTRASSE 22, POSTFACH 86 04 20, D-81679 MUNICH, GERMANY SN 0032-678X J9 PRAKT METALLOGR-PR M JI Prakt. Metallogr.-Pract. Metallogr. PD MAY PY 1999 VL 36 IS 5 BP 250 EP 263 PG 20 WC Metallurgy & Metallurgical Engineering SC Metallurgy & Metallurgical Engineering GA 213KK UT WOS:000081271500002 ER PT J AU Phillips, RM Sprehn, DW AF Phillips, RM Sprehn, DW TI High-power klystrons for the Next Linear Collider SO PROCEEDINGS OF THE IEEE LA English DT Article DE accelerator RF system; klystron; microwave circuits; microwave power amplifier; microwave tubes; permanent magnets AB The Stanford Linear Accelerator Center (SLAC) version of the 1 TeV Next Linear Collider (NLC) requires a 4:1 increase in drive frequency, from the 2.85 GHz of the .1 TeV Stanford Linear Collider (SLC) to 11:4 GHz for the NLC. More than eight years have gone into the development of a new 75-MW klystron for powering the NLC. The increase in power density and surface RF gradient at the higher frequency have rendered previous RF window and circuit designs unusable. Following numerous catastrophic gun, cavity, and window failures, new designs have evolved that solved the problems. As history's most ambitious klystron development enters its last year, the results includes a robust 75-MW peak power solenoid-focused, 50% efficient klystron. Not far behind is a 60-75-MW periodic permanent magnet (PPM)-focused 60% efficient version that will reduce the NLC electric power bill by tens of millions of dollars per year. C1 Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Phillips, RM (reprint author), Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. NR 17 TC 17 Z9 17 U1 1 U2 3 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI PISCATAWAY PA 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA SN 0018-9219 J9 P IEEE JI Proc. IEEE PD MAY PY 1999 VL 87 IS 5 BP 738 EP 751 DI 10.1109/5.757253 PG 14 WC Engineering, Electrical & Electronic SC Engineering GA 189XP UT WOS:000079931700004 ER PT J AU Freund, HP Neil, GR AF Freund, HP Neil, GR TI Free-electron lasers: Vacuum electronic generators of coherent radiation SO PROCEEDINGS OF THE IEEE LA English DT Review DE free-electron on lasers; IR spectroscopy; pulse probe spectroscopy; self-amplified spontaneous emission; sum frequency generation; undulators ID VEPP-3 STORAGE-RING; INTRACAVITY COMPTON BACKSCATTERING; TESLA-TEST-FACILITY; ULTRAVIOLET REGIONS; OPTICAL KLYSTRON; HIGH-GAIN; VIBRATIONAL SPECTROSCOPY; 3-DIMENSIONAL THEORY; MATERIALS SCIENCE; TAPERED-WIGGLER AB Vacuum electronic sources have shown marked improvement since the invention of the magnetron before World War II, and dramatic increases in both average powers and frequencies have been achieved. Of course, many of these gains have been achieved by the development of different devices. The typical development pattern for a given device exhibits an initial period of rapid improvement followed by, a plateau determined by technological ol physical limitations on the concept. Slow wave devices such as magnetrons and/or klystrons operate efficiently at frequencies up through X-band or somewhat higher. Helix or coupled cavity traveling-wave tubes are used for various applications at frequencies ranging up through W-band. At still higher frequencies, fast wave devices such as gyrotrons and free-electron lasers are required for high-power operation. The free-electron laser concept is unique in that the mechanism is applicable across the entire electromagnetic spectrum; free-electron lasers have been built at wavelengths from microwaves through the ultraviolet, and plans al-e under development for X-ray systems. Our put-pose in this paper is to describe the principal directions of free-electron laser research at the present time. To this end, we fir-st give a brief tutorial of the physics underlying the concept and then describe the principal development paths under way. C1 Sci Applicat Int Corp, Mclean, VA 22102 USA. Thomas Jefferson Natl Accelerator Facil, Newport News, VA 23606 USA. RP Freund, HP (reprint author), Sci Applicat Int Corp, Mclean, VA 22102 USA. NR 137 TC 27 Z9 27 U1 2 U2 14 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9219 J9 P IEEE JI Proc. IEEE PD MAY PY 1999 VL 87 IS 5 BP 782 EP 803 DI 10.1109/5.757255 PG 22 WC Engineering, Electrical & Electronic SC Engineering GA 189XP UT WOS:000079931700006 ER PT J AU Nation, JA Schachter, L Mako, FM Len, LK Peter, W Tang, CM Srinivasan-Rao, T AF Nation, JA Schachter, L Mako, FM Len, LK Peter, W Tang, CM Srinivasan-Rao, T TI Advances in cold cathode physics and technology SO PROCEEDINGS OF THE IEEE LA English DT Review DE cathodes; electron beams; electron emission; ferroelectric materials; microwave tubes; linear accelerators; photo electricity ID FIELD-EMITTER ARRAYS; TRANSITION-METAL CARBIDES; ELECTRON-EMISSION; FERROELECTRIC CATHODES; MICROWAVE-AMPLIFIER; PHOTOEMISSION; LASER; PERFORMANCE; PHOTOCATHODES; PHOTOINJECTOR AB We review recent progress in the physics and technology of cold cathode electron emitters. The characteristics of emission from field emitter a,lays, photocathodes, and ferroelectrics are presented, together with a summary of the understanding of the physics involved. The paper concludes with a description of L-band micropulse gun, based on secondary emission in an RF cavity. Emphasis is placed on cathode development for electron guns to drive microwave robes and RF accelerators. C1 Cornell Univ, Sch Elect Engn, Ithaca, NY 14853 USA. Cornell Univ, Plasma Studies Lab, Ithaca, NY 14853 USA. Technion Israel Inst Technol, Dept Elect Engn, IL-32000 Haifa, Israel. FM Technol Inc, Fairfax, VA 22032 USA. Creaty MicroTech Inc, Potomac, MD 20854 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. RP Nation, JA (reprint author), Cornell Univ, Sch Elect Engn, Phillips Hall, Ithaca, NY 14853 USA. NR 138 TC 56 Z9 57 U1 1 U2 11 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 USA SN 0018-9219 J9 P IEEE JI Proc. IEEE PD MAY PY 1999 VL 87 IS 5 BP 865 EP 889 DI 10.1109/5.757258 PG 25 WC Engineering, Electrical & Electronic SC Engineering GA 189XP UT WOS:000079931700009 ER PT J AU Post, HN Thomas, MG DeBlasio, R AF Post, HN Thomas, MG DeBlasio, R TI Introduction to special issue on PV systems performance and reliability SO PROGRESS IN PHOTOVOLTAICS LA English DT Editorial Material AB The papers in this special issue have been selected from the systems and balance-of-systems sessions at the 1998 Photovoltaic Performance and Reliability Workshop. The Workshop was held November 3-5, 1998 and hosted by the Florida Solar Energy Center, Cocoa Beach, Florida under sponsorship, of the US National Center for Photovoltaics (National Renewable Energy Laboratory and Sandia National Laboratories). The topics and issues addressed by these papers were identified in an invited review paper on PV systems by the guest editors. Their work was published earlier this year in Volume 7, Number 1 of Progress in Photovoltaics ('Photovoltaic Systems: An End-of-Millennium Review'). Experts in the PV community were asked to make presentations on these topics at the workshop. The papers that follow, are the results of that effort. We have organized the papers by topic: (1) codes and standards; (2) reliability; (3) design issues; and (4) commercialization. Published in 1999 by John Wiley & Sons, Ltd This article is a US Government work and is in the public domain in the United States. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Post, HN (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 0 TC 0 Z9 0 U1 0 U2 2 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 MAY-JUN PY 1999 VL 7 IS 3 BP 153 EP 154 DI 10.1002/(SICI)1099-159X(199905/06)7:3<153::AID-PIP262>3.0.CO;2-U PG 2 WC Energy & Fuels; Materials Science, Multidisciplinary; Physics, Applied SC Energy & Fuels; Materials Science; Physics GA 219KR UT WOS:000081606900001 ER PT J AU Bower, W DeBlasio, R AF Bower, W DeBlasio, R TI Code requirements and standards for installations of photovoltaic systems in the US SO PROGRESS IN PHOTOVOLTAICS LA English DT Article; Proceedings Paper CT Systems and Balance-of-Systems Session, at the 1998 Photovoltaic Performance and Reliability Workshop CY NOV 03-05, 1998 CL COCOA BEACH, FLORIDA SP US Natl Ctr Photovoltaics, Natl Renewable Energy Lab, Sandia Natl Labs AB Electrical code requirements and a broad base of standards for PV installations in the US have been written. The National Electrical Code(R) (NEC(R)) focuses primarily on electrical system installation requirements in the US. The NEC addresses both fire and personnel safety. Tills paper describes recent efforts of the PV industry in the CIS and the resulting requirements in the 1999 National Electrical Code - Article 690 - Solar Photovoltaic Systems. It provides an overview of the most significant changes that appeal in Article 690 of the 1999 edition of the NEC. A summary of the Institute of Electrical and Electronic Engineers (IEEE) PV standards and current standards development efforts is also provided, Related and coordinated efforts of the other standards-making groups are also briefly reviewed. Published irt 1999 bt, John Wiley & Sons, Ltd This article is a US Government work and is in the public domain in the United States. C1 Sandia Natl Labs, PV Syst Applicat Dept, Albuquerque, NM 87185 USA. Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Bower, W (reprint author), Sandia Natl Labs, PV Syst Applicat Dept, MS-0753, Albuquerque, NM 87185 USA. NR 11 TC 1 Z9 1 U1 0 U2 1 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 1062-7995 J9 PROG PHOTOVOLTAICS JI Prog. Photovoltaics PD MAY-JUN PY 1999 VL 7 IS 3 BP 155 EP 164 DI 10.1002/(SICI)1099-159X(199905/06)7:3<155::AID-PIP269>3.0.CO;2-3 PG 10 WC Energy & Fuels; Materials Science, Multidisciplinary; Physics, Applied SC Energy & Fuels; Materials Science; Physics GA 219KR UT WOS:000081606900002 ER PT J AU Maish, A AF Maish, A TI Defining requirements for improved photovoltaic system reliability SO PROGRESS IN PHOTOVOLTAICS LA English DT Article; Proceedings Paper CT Systems and Balance-of-Systems Session, at the 1998 Photovoltaic Performance and Reliability Workshop CY NOV 03-05, 1998 CL COCOA BEACH, FLORIDA SP US Natl Ctr Photovoltaics, Natl Renewable Energy Lab, Sandia Natl Labs AB Reliable systems are all essential ingredient of any technology progressing toward commercial maturity, and large-scale deployment. This paper defines reliability as meeting system functional requirements, and then develops a framework to understand and quantify photovoltaic (PV) system reliability based on initial and ongoing costs and system value. The core elements necessary to achieve reliable PV systems are reviewed. These include appropriate system design, satisfactory component reliability, and proper installation and servicing. Reliability status, key issues, and present needs in system reliability are summarized for grid-tied applications. Published in 1999 by John Wiley & Sons, Ltd. This article is a US Government work and is ill the public domain in the United States. C1 Sandia Natl Labs, PV Syst Applicat Dept, Albuquerque, NM 87185 USA. RP Maish, A (reprint author), Sandia Natl Labs, PV Syst Applicat Dept, POB 5800, Albuquerque, NM 87185 USA. NR 20 TC 16 Z9 16 U1 0 U2 0 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 MAY-JUN PY 1999 VL 7 IS 3 BP 165 EP 173 DI 10.1002/(SICI)1099-159X(199905/06)7:3<165::AID-PIP270>3.0.CO;2-S PG 9 WC Energy & Fuels; Materials Science, Multidisciplinary; Physics, Applied SC Energy & Fuels; Materials Science; Physics GA 219KR UT WOS:000081606900003 ER PT J AU Ginn, JW AF Ginn, JW TI Testing and development of a 30-kVA hybrid inverter: Lessons learned and reliability implications SO PROGRESS IN PHOTOVOLTAICS LA English DT Article; Proceedings Paper CT Systems and Balance-of-Systems Session, at the 1998 Photovoltaic Performance and Reliability Workshop CY NOV 03-05, 1998 CL COCOA BEACH, FLORIDA SP US Natl Ctr Photovoltaics, Natl Renewable Energy Lab, Sandia Natl Labs AB A 30-kVA Trace Technologies hybrid power processor was specified and extensively tested at the Sandia inverter test facility. Trade Technologies made modifications, primarily involving: the control system, in response to suggestions by Sandia and Arizona Public Service (APS) personnel. The modifications should make the inverter more universally applicable and less site-specific so that it call he applied in various sites with minimal field interaction required from the design engineer. The project emphasized the importance of battery management, generator selection, and site load management to the performance and reliability of hybrid power systems. Published in 1999 by John Wiley & Sons, Ltd This article is a US Government work and is in the public domain by the United States. C1 Sandia Natl Labs, Photovolta Syst Components Dept, Albuquerque, NM 87185 USA. RP Ginn, JW (reprint author), Sandia Natl Labs, Photovolta Syst Components Dept, POB 5800, Albuquerque, NM 87185 USA. NR 3 TC 1 Z9 1 U1 0 U2 1 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 1062-7995 J9 PROG PHOTOVOLTAICS JI Prog. Photovoltaics PD MAY-JUN PY 1999 VL 7 IS 3 BP 191 EP 198 PG 8 WC Energy & Fuels; Materials Science, Multidisciplinary; Physics, Applied SC Energy & Fuels; Materials Science; Physics GA 219KR UT WOS:000081606900006 ER PT J AU Itoh, N Kanasaki, J Xu, J AF Itoh, N Kanasaki, J Xu, J TI Laser-induced desorption from STM-selected semiconductor sites SO PROGRESS IN SURFACE SCIENCE LA English DT Review ID SCANNING-TUNNELING-MICROSCOPY; SI(111)-7X7 SURFACE; ELECTRONIC-STRUCTURE; PARTICLE-EMISSION; SI(100) SURFACES; BOND BREAKING; RECONSTRUCTION; EXCITATION; ABLATION; DEFECTS AB We review recent scanning tunneling microscopy studies of laser-induced site-selective removal of atoms from Si surfaces. We discuss the possible mechanism of the process, which is entirely due to bond scission via electronic excitation. It is pointed out that any bond scission of electronic origin on Si surfaces needs a localized excited state. Experimental results of laser-induced desorption from the Si(111)7 x 7 surfaces, on which the localized excited state is considered to be formed preferentially at the adatom site, indicate that there is a selectivity for the removal of non-equivalent adatoms. The removal of the outermost layer of the Si(100)2 x 1 surface reveals an unreconstructed surface, which is more stable against laser irradiation than the outermost surface. Uses of site-selectiveness for surface modification are also described. (C) 1999 Elsevier Science Ltd. All rights reserved. C1 Nagoya Univ, Grad Sch Sci, Nagoya, Aichi 4648602, Japan. Osaka Inst Technol, Osaka 5730196, Japan. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Kanasaki, J (reprint author), Nagoya Univ, Grad Sch Sci, Nagoya, Aichi 4648602, Japan. EM kanasaki@edu3.phys.nagoya-u.ac.jp RI Kanasaki, Jun'ichi/H-2556-2014 OI Kanasaki, Jun'ichi/0000-0001-5888-6498 NR 36 TC 5 Z9 5 U1 1 U2 5 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0079-6816 J9 PROG SURF SCI JI Prog. Surf. Sci. PD MAY PY 1999 VL 61 IS 1 BP 1 EP 19 DI 10.1016/S0079-6816(99)00007-6 PG 19 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA 216MV UT WOS:000081447200001 ER PT J AU Schenkel, T Hamza, AV Barnes, AV Schneider, DH AF Schenkel, T Hamza, AV Barnes, AV Schneider, DH TI Interaction of slow, very highly charged ions with surfaces SO PROGRESS IN SURFACE SCIENCE LA English DT Review ID X-RAY-EMISSION; ELASTIC-COLLISION SPIKES; LARGE-ANGLE SCATTERING; HOLLOW NITROGEN-ATOMS; ENERGY-LOSS; AR IONS; ELECTRON-EMISSION; GRAZING-INCIDENCE; AL SURFACE; AU(111) SURFACE AB The present article reviews recent advances in the studies of the interaction of slow (nu < nu(Bohr)), very highly charged ions (such as Xe(52+) and Au(69+)) With surfaces of metals, semiconductors, and insulators (including biological materials). After a brief summary of past developments, we describe key experimental techniques for studies of secondary particle emission and the de-excitation dynamics of the highly charged ions. Recent progress in measurement and determination of the mechanisms leading to secondary electron yields, secondary ion yields and total sputtering yields will be discussed. The deexcitation dynamics are addressed in experiments on projectile neutralization and energy loss in thin films of material. We review the theoretical concepts briefly and introduce theoretical models in the discussion of experimental results. Following the presentation of fundamental studies we will address emerging applications of slow, very highly charged ions in surface analysis and surface modification. (C) 1999 Published by Elsevier Science Ltd. All rights reserved. C1 Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Schenkel, T (reprint author), Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. EM schenkel2@llnl.gov NR 179 TC 164 Z9 173 U1 1 U2 14 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0079-6816 J9 PROG SURF SCI JI Prog. Surf. Sci. PD MAY-JUN PY 1999 VL 61 IS 2-4 BP 23 EP 84 DI 10.1016/S0079-6816(99)00009-X PG 62 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA 216MW UT WOS:000081447300002 ER PT J AU Pons, J Rajpal, A Kirsch, JF AF Pons, J Rajpal, A Kirsch, JF TI Energetic analysis of an antigen/antibody interface: Alanine scanning mutagenesis and double mutant cycles on the HyHEL-10/lysozyme interaction SO PROTEIN SCIENCE LA English DT Article DE alanine scan mutagenesis; antibody; antigen; double mutant cycles; epitope mapping; hen egg-white lysozyme; monoclonal antibody HyHEL-10; protein-protein interaction ID SITE-DIRECTED MUTAGENESIS; GROWTH-HORMONE RECEPTOR; MONOCLONAL-ANTIBODY HYHEL10; PROTEIN-PROTEIN COMPLEX; BINDING INTERACTIONS; SPECIES-SPECIFICITY; CHICKEN LYSOZYME; COMBINING SITES; ANTIGEN COMPLEX; FAB COMPLEX AB Alanine scanning mutagenesis of the HyHEL-10 paratope of the HyHEL-10/HEWL complex demonstrates that the energetically important side chains (hot spots) of both partners are in contact. A plot of Delta Delta G(HyHEL-10_mutant) vs. Delta Delta G(HEWL_mutant) for the five of six interacting side-chain hydrogen bonds is linear (Slope = 1). Only 3 of the 13 residues in the HEWL epitope contribute >4 kcal/mol to the free energy of formation of the complex when replaced by alanine, but 6 of the 12 HyHEL-10 paratope amino acids do. Double mutant cycle analysis of the single crystallographically identified salt bridge, D32(H)/K97. shows that there is a significant energetic penalty when either partner is replaced with a neutral side-chain amino acid, but the D32(H)N/K97M complex is as stable as the WT. The role of the disproportionately high number of Tyr residues in the CDR was evaluated by comparing the Delta Delta G values of the Tyr --> Phe vs. the corresponding Tyr --> Ala mutations. The nonpolar contacts in the light chain contribute only about one-half of the total Delta Delta G observed for the Tyr --> Ala mutation, while they are significantly more important in the heavy chain. Replacement of the N31(L)/K96 hydrogen bond with a salt bridge, N31D(L)/K96, destabilizes the complex by 1.4 kcal/mol, The free energy of interaction, Delta Delta G(int), obtained from double mutant cycle analysis showed that Delta Delta G(int) for any complex for which the HEWL residue probed is a major immunodeterminant is very close to the loss of free energy observed for the HyHEL-10 single mutant. Error propagation analysis of double mutant cycles shows that data of atypically high precision an required to use this method meaningfully, except where large Delta Delta G values are analyzed. C1 Univ Calif Berkeley, Dept Mol & Cell Biol, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Adv Mat, Berkeley, CA 94720 USA. RP Kirsch, JF (reprint author), Univ Calif Berkeley, Dept Mol & Cell Biol, 229 Stanley Hall, Berkeley, CA 94720 USA. NR 41 TC 81 Z9 81 U1 0 U2 9 PU CAMBRIDGE UNIV PRESS PI NEW YORK PA 40 WEST 20TH STREET, NEW YORK, NY 10011-4211 USA SN 0961-8368 J9 PROTEIN SCI JI Protein Sci. PD MAY PY 1999 VL 8 IS 5 BP 958 EP 968 PG 11 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 192ZE UT WOS:000080109000002 PM 10338006 ER PT J AU Zhang, XJ Lin, Y Jonah, CD AF Zhang, XJ Lin, Y Jonah, CD TI Anion and electron solvation in alcohols SO RADIATION PHYSICS AND CHEMISTRY LA English DT Review ID BENZOPHENONE ANION; PICOSECOND SOLVATION; PULSE-RADIOLYSIS; POLAR LIQUIDS; EXCESS ELECTRONS; DYNAMICS; SOLVENTS; TIME; FLUORESCENCE; TEMPERATURE AB Pulse radiolytic techniques have been used to measure the solvation of anions and electrons in alcohols. The results have shown the importance of the microscopic liquid structure in the solvation process. The activation energy for benzophenone solvation is equal to the hydrogen-bond energy for the liquids, which shows that the solvent reorganization requires the breaking of the hydrogen bonds between solvent molecules. For electron solvation, primary alcohols have a lower activation energy because the initial hydrogen-bonded structure of the liquid is amenable to solvation. The solvation of an electron in a secondary alcohol requires require hydrogen-bond breakage. (C) 1999 Published by Elsevier Science Ltd. All rights reserved. C1 Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. RP Zhang, XJ (reprint author), Argonne Natl Lab, Div Chem, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 45 TC 12 Z9 12 U1 1 U2 6 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0969-806X J9 RADIAT PHYS CHEM JI Radiat. Phys. Chem. PD MAY PY 1999 VL 54 IS 5 BP 433 EP 440 DI 10.1016/S0969-806X(97)00315-0 PG 8 WC Chemistry, Physical; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical SC Chemistry; Nuclear Science & Technology; Physics GA 182FT UT WOS:000079488900001 ER PT J AU Tello, C Villela, T Wuensche, CA Figueiredo, N Torres, S Bersanelli, M Bensadoun, M De Amici, G Smoot, GF AF Tello, C Villela, T Wuensche, CA Figueiredo, N Torres, S Bersanelli, M Bensadoun, M De Amici, G Smoot, GF TI Diffraction analysis of a double-shielded antenna in the Fraunhofer and Fresnel regimes: Model predictions SO RADIO SCIENCE LA English DT Article ID RADIO-CONTINUUM EMISSION; FREQUENCIES; MAP; SKY AB We analytically investigate the use of a wire mesh ground screen (fence) and a halo of extension panels around a helically fed parabolic reflector in order to estimate the ground contribution to the antenna noise temperature in an experiment aimed at surveying the sky at decimeter wavelengths. We use geometric diffraction theory to model the effect of these screening and blocking shields when scanning in azimuth at tilt angles from zenith in the range 0 degrees greater than or equal to Z greater than or equal to 45 degrees. We report estimates based on existing formulas for monofilar axial-mode helical antennas with expected low-level sidelobes in the direction of the halo region. As long as there is no significant coupling between the near-field patterns of both the feed and the diffracting halo, estimates using the Fraunhofer approximation agree with those calculated with the Fresnel approach at a tilt angle Z(eq), which increases with the proximity of the diffracting edge from the near-/far-field boundary of the feed pattern. Our estimates show that for a fence of some IO-dB attenuation and high enough to level out the horizon profile at the prime focus of the antenna, the diffracted components dominate the contribution for tilt angles Z less than or similar to 35 degrees The fence is the main diffractor when Z greater than or similar to 20 degrees, but for Z greater than or similar to 25 degrees its contribution becomes insensitive to the presence of the halo. On the other hand, if the attenuation is low (<1dB), the increase in ground solid angle with tilt angle makes the contribution due to transmission and ground exposure the dominant one. C1 Inst Nacl Pesquisas Espaciais, Div Astrofis, BR-12201970 Sao Jose Dos Campos, SP, Brazil. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. CNR, Ist Fis Cosm, I-20133 Milan, Italy. TRW Co Inc, Redondo Beach, CA 90278 USA. Escola Fed Engn Itajuba, BR-37500000 Itajuba, MG, Brazil. Univ Nacl Colombia, Astron Observ, Bogota, Colombia. Ctr Int Fis, Bogota, Colombia. RP Tello, C (reprint author), Inst Nacl Pesquisas Espaciais, Div Astrofis, CP 515, BR-12201970 Sao Jose Dos Campos, SP, Brazil. RI Figueiredo, Newton/F-9976-2011 NR 16 TC 3 Z9 3 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0048-6604 J9 RADIO SCI JI Radio Sci. PD MAY-JUN PY 1999 VL 34 IS 3 BP 575 EP 586 DI 10.1029/1998RS900031 PG 12 WC Astronomy & Astrophysics; Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Remote Sensing; Telecommunications SC Astronomy & Astrophysics; Geochemistry & Geophysics; Meteorology & Atmospheric Sciences; Remote Sensing; Telecommunications GA 201NT UT WOS:000080602200003 ER PT J AU Holland, N Ahlborn, T Turteltaub, K Markee, C Moore, D Wyrobek, AJ Smith, MT AF Holland, N Ahlborn, T Turteltaub, K Markee, C Moore, D Wyrobek, AJ Smith, MT TI Acrylamide causes preimplantation abnormalities in embryos and induces chromatin-adducts in male germ cells of mice SO REPRODUCTIVE TOXICOLOGY LA English DT Article DE acrylamide; genotoxicity; chromatin-adducts; sperm; preimplantation abnormalities ID ACCELERATOR MASS-SPECTROMETRY; GENETIC-DAMAGE; MOUSE; DNA; RATS; BLASTOCYSTS; BINDING; CYTOGENETICS; MICRONUCLEI; EXPOSURE AB Acrylamide, a known male postmeiotic germ cell mutagen, caused a dose-dependent increase in the frequency of morphologic abnormalities in preimplantation embryos. Single-cell eggs, growth retardation, and blastomere lysis were detected after paternal treatment with acrylamide (10 to 50 mg/kg, 5 d). The major effects were seen at weeks 1 to 3 after male treatment, with the highest level of abnormalities at the first week (>90% vs. 5% in control). The frequency of abnormal four-day embryos was similar to preimplantation loss assessed at 15 to 16 d p.c. A > 100-fold elevation of chromatin adducts in sperm was observed during 1st and 2nd week after treatment, after which adduct levels decreased to baseline level. However, morphologic defects in embryos are not fully explained by the spermatid adduct curve. These findings demonstrate the effects of paternal exposure to acrylamide on preimplantation development and indicate a potential risk to the offspring of men exposed to acrylamide. (C) 1999 Elsevier Science Inc. C1 Univ Calif Berkeley, Sch Publ Hlth, Div Environm Hlth Sci, Berkeley, CA 94720 USA. Lawrence Livermore Natl Lab, Livermore, CA USA. RP Holland, N (reprint author), Univ Calif Berkeley, Sch Publ Hlth, Div Environm Hlth Sci, 217 Warren Hall, Berkeley, CA 94720 USA. FU NIEHS NIH HHS [ES04705, Y01-ES-10203-00, P30 ES01826] NR 50 TC 23 Z9 27 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0890-6238 J9 REPROD TOXICOL JI Reprod. Toxicol. PD MAY-JUN PY 1999 VL 13 IS 3 BP 167 EP 178 DI 10.1016/S0890-6238(99)00011-8 PG 12 WC Reproductive Biology; Toxicology SC Reproductive Biology; Toxicology GA 202BK UT WOS:000080632100002 PM 10378466 ER PT J AU Yun, W Lai, B Cai, Z Maser, J Legnini, D Gluskin, E Chen, Z Krasnoperova, AA Vladimirsky, Y Cerrina, F Di Fabrizio, E Gentili, M AF Yun, W Lai, B Cai, Z Maser, J Legnini, D Gluskin, E Chen, Z Krasnoperova, AA Vladimirsky, Y Cerrina, F Di Fabrizio, E Gentili, M TI Nanometer focusing of hard x rays by phase zone plates SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article ID FABRICATION AB Focusing of 8 keV x rays to a spot size of 150 and 90 nm full width at half maximum have been demonstrated at the first- and third-order foci, respectively, of a phase zone plate (PZP). The PZP has a numerical aperture of 1.5 mrad and focusing efficiency of 13% for 8 keV x rays. A flux density gain of 121 000 was obtained at the first-order focus. In this article, the fabrication of the PZP and its experimental characterization are presented and some special applications are discussed. (C) 1999 American Institute of Physics. [S0034-6748(99)02705-7]. C1 Argonne Natl Lab, Expt Facil Div, Argonne, IL 60439 USA. Univ Wisconsin, Dept Elect & Comp Engn, Ctr Xray Lithog, Madison, WI 53706 USA. CNR, Ist Elettron Stato Solido, I-00156 Rome, Italy. RP Yun, W (reprint author), Argonne Natl Lab, Expt Facil Div, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Maser, Jorg/K-6817-2013 NR 17 TC 177 Z9 180 U1 2 U2 18 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD MAY PY 1999 VL 70 IS 5 BP 2238 EP 2241 DI 10.1063/1.1149744 PG 4 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 193AU UT WOS:000080113600006 ER PT J AU Lexa, D AF Lexa, D TI Hermetic sample enclosure for simultaneous differential scanning calorimetry/synchrotron powder x-ray diffraction SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article AB A hermetic sample enclosure for performing simultaneous differential scanning calorimetry/synchrotron powder x-ray diffraction was designed, and a prototype was fabricated. The enclosure design is based upon a Perkin-Elmer DSC-2C measuring head with modifications allowing an unobstructed x-ray beam access to the sample in a controlled-atmosphere environment. The modifications to the measuring head base are limited to exposing the sample and reference platinum cups and providing a mating surface for the head cover. A completely new head cover, featuring semicylindrical beryllium x-ray windows, is hermetically attached to the base. A new graphite sample pan, addressing the conflicting requirements of differential scanning calorimetry and powder x-ray diffraction, was designed, and multiple pans were fabricated. An alternative temperature measurement and control system was developed and assembled. The complete system was tested in three experiments. No problems were encountered with diffraction data acquisition and temperature control, however, calorimetric resolution was mediocre. The alternative temperature measurement and control system will have to be optimized. (C) 1999 American Institute of Physics. [S0034-6748(99)03705-3]. C1 Argonne Natl Lab, Div Chem Technol, Argonne, IL 60439 USA. RP Lexa, D (reprint author), Argonne Natl Lab, Div Chem Technol, 9700 S Cass Ave, Argonne, IL 60439 USA. RI ID, MRCAT/G-7586-2011 NR 4 TC 9 Z9 9 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD MAY PY 1999 VL 70 IS 5 BP 2242 EP 2245 DI 10.1063/1.1149745 PG 4 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 193AU UT WOS:000080113600007 ER PT J AU Whittum, DH Kolomensky, Y AF Whittum, DH Kolomensky, Y TI Analysis of an asymmetric resonant cavity as a beam monitor SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article AB We analyze the excitation of an arbitrary, externally coupled resonant structure by a charged particle beam, providing a rigorous formulation of the effect of spurious modes and intrinsic mode nonlinearity on inferred beam coordinates. Results are illustrated for a two-cavity system employed for beam-position monitoring with an idealized front-end signal processor. (C) 1999 American Institute of Physics. [S0034-6748(99)01403-3]. C1 Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. CALTECH, Pasadena, CA 91125 USA. RP Whittum, DH (reprint author), Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RI Kolomensky, Yury/I-3510-2015 OI Kolomensky, Yury/0000-0001-8496-9975 NR 15 TC 15 Z9 15 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD MAY PY 1999 VL 70 IS 5 BP 2300 EP 2313 DI 10.1063/1.1149756 PG 14 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 193AU UT WOS:000080113600018 ER PT J AU Britvich, GI Chumakov, AA Ronningen, RM Blue, RA Heilbronn, LH AF Britvich, GI Chumakov, AA Ronningen, RM Blue, RA Heilbronn, LH TI Measurements of thick target neutron yields and shielding studies using beams of He-4, C-12 and O-16 at 155 MeV/nucleon from the K1200 cyclotron at the National Superconducting Cyclotron Laboratory SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article ID CARBON; LEAD; IONS AB Measurements of neutrons from a thick target of Hevimet were made, using beams of He-4, C-12, and O-16 ions at 155 MeV per nucleon. These measurements were made both inside and outside of thick concrete shielding, using Bonner-sphere techniques. Yields, spectra, and spectral integral quantities were obtained. The neutron yields were parameterized, and a Moyer-model approach was taken to estimate the dose-equivalent outside of the thick concrete shielding. The effect of local iron shielding, and the dose equivalent outside of iron roof shielding were also investigated. Finally, two methods to obtain neutron field integral values, the "reconstructed spectra'' and "six-spheres'' methods, were compared. The measurements and analyses should prove useful to other present or planned medium-energy heavy-ion accelerator facilities. (C) 1999 American Institute of Physics. [S0034-6748(99)01505-1]. C1 Superconducting Super Collider Lab, Waxahachee, TX 75165 USA. Protvino High Energy Phys Inst, Protvino 142284, Russia. Michigan State Univ, Natl Supercond Cyclotron Lab, E Lansing, MI 48824 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Britvich, GI (reprint author), Protvino High Energy Phys Inst, Protvino 142284, Russia. RI Heilbronn, Lawrence/J-6998-2013 OI Heilbronn, Lawrence/0000-0002-8226-1057 NR 24 TC 6 Z9 6 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD MAY PY 1999 VL 70 IS 5 BP 2314 EP 2324 DI 10.1063/1.1149757 PG 11 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 193AU UT WOS:000080113600019 ER PT J AU Hayes, JM Reinot, T Shields, P Small, GJ AF Hayes, JM Reinot, T Shields, P Small, GJ TI A liquid helium cryostat for the study of pressure effects on hole burned spectra of hyperquenched glassy films SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article ID ALUMINUM PHTHALOCYANINE TETRASULFONATE; SOLID WATER; TRANSITION AB A liquid helium cryostat that allows for thermospray deposition of samples in vacuum and subsequent pressure dependent studies up to 150 atm is described. Performance of the cryostat is illustrated by study of the pressure-induced shifts and broadening of holes burned in the lowest energy absorption band of aluminum phthalocyanine tetrasulfonate in hyperquenched glassy water. The hole widths exhibit an unusual dependence upon the pressure at which they are burned and also a linear frequency shift which depends upon the sign of the pressure change. (C) 1999 American Institute of Physics. [S0034-6748(99)00705-4]. C1 Iowa State Univ, Ames Lab, Ames, IA 50014 USA. Iowa State Univ, Dept Chem, Ames, IA 50014 USA. Janis Res Co Inc, Wilmington, MA 01887 USA. RP Hayes, JM (reprint author), Iowa State Univ, Ames Lab, Ames, IA 50014 USA. NR 22 TC 3 Z9 3 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD MAY PY 1999 VL 70 IS 5 BP 2454 EP 2457 DI 10.1063/1.1149776 PG 4 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA 193AU UT WOS:000080113600041 ER PT J AU Nagel, K AF Nagel, K TI Hell on wheels - New computer models are confirming what commuters have long suspected: traffic jams can come out of nowhere SO SCIENCES-NEW YORK LA English DT Article C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Nagel, K (reprint author), Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU NEW YORK ACAD SCIENCES PI NEW YORK PA 2 E 63RD ST, NEW YORK, NY 10021 USA SN 0036-861X J9 SCIENCES JI Sci.-New York PD MAY-JUN PY 1999 VL 39 IS 3 BP 26 EP 31 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 188PJ UT WOS:000079856800016 ER PT J AU Mitchell, E Kuhn, P Garman, E AF Mitchell, E Kuhn, P Garman, E TI Demystifying the synchrotron trip: a first time user's guide SO STRUCTURE WITH FOLDING & DESIGN LA English DT Article ID X-RAY-DIFFRACTION; DATA-COLLECTION; PROTEIN CRYSTALLOGRAPHY; CRYOCRYSTALLOGRAPHY; RADIATION; MOSAICITY; STRATEGY; DETECTOR; CRYSTALS C1 European Synchrotron Radiat Facil, F-38043 Grenoble, France. Stanford Synchrotron Radiat Lab, Stanford, CA 94309 USA. Univ Oxford, Dept Biochem, Lab Mol Biophys, Oxford OX1 3QU, England. RP Mitchell, E (reprint author), European Synchrotron Radiat Facil, BP 220, F-38043 Grenoble, France. NR 18 TC 12 Z9 13 U1 0 U2 1 PU CURRENT BIOLOGY LTD PI LONDON PA 84 THEOBALDS RD, LONDON WC1X 8RR, ENGLAND SN 0969-2126 J9 STRUCT FOLD DES JI Struct. Fold. Des. PD MAY PY 1999 VL 7 IS 5 BP R111 EP R121 DI 10.1016/S0969-2126(99)80063-X PG 11 WC Biochemistry & Molecular Biology; Biophysics; Cell Biology SC Biochemistry & Molecular Biology; Biophysics; Cell Biology GA 201CL UT WOS:000080577000004 PM 10378266 ER PT J AU Paranthaman, M Lee, DF Goyal, A Specht, ED Martin, PM Cui, X Mathis, JE Feenstra, R Christen, DK Kroeger, DM AF Paranthaman, M Lee, DF Goyal, A Specht, ED Martin, PM Cui, X Mathis, JE Feenstra, R Christen, DK Kroeger, DM TI Growth of biaxially textured RE2O3 buffer layers on rolled-Ni substrates using reactive evaporation for HTS-coated conductors SO SUPERCONDUCTOR SCIENCE & TECHNOLOGY LA English DT Article ID CRITICAL-CURRENT DENSITY; SUPERCONDUCTING TAPES; DEPOSITION; FILMS; METAL AB In an effort to develop alternative single buffer layer architectures for YBCO (YBa2Cu3O7-y) coated conductors, we have studied RE2O3 (RE = Y, and rare earths) as candidate materials. High-quality Y2O3, Gd2O3 and Yb2O3 buffer layers were grown epitaxially on biaxially textured Ni (100) substrates using reactive electron beam evaporation. Using thermodynamic considerations for the formation of metal oxides, we employed both reducing atmospheres and water vapour to oxidize the film in situ to form stoichiometric RE2O3 We have also prevented NiO formation at the substrate-film interface during this process. Detailed x-ray studies have shown that the Y2O3, Gd2O3 and Yb2O3 films were grown with a single epitaxial orientation. The lattice mismatch between YBCO and Gd2O3 was small as compared with that of YBCO with other rare earth oxides. SEM micrographs indicated that similar to 0.5 mu m thick Y2O3 films On rolled-Ni substrates were dense, continuous and crack free. A high J(c) of 1.8 x 10(6) A cm(-2) at 77 K and self-field was obtained on YBCO films grown on alternative buffer layers with a layer sequence of YBCO/Yb2O3 (sputtered)TY2O3 (e-beam)/Ni. C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Paranthaman, M (reprint author), Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RI Christen, David/A-9709-2008; Specht, Eliot/A-5654-2009; Paranthaman, Mariappan/N-3866-2015 OI Specht, Eliot/0000-0002-3191-2163; Paranthaman, Mariappan/0000-0003-3009-8531 NR 19 TC 65 Z9 71 U1 0 U2 6 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0953-2048 J9 SUPERCOND SCI TECH JI Supercond. Sci. Technol. PD MAY PY 1999 VL 12 IS 5 BP 319 EP 325 DI 10.1088/0953-2048/12/5/313 PG 7 WC Physics, Applied; Physics, Condensed Matter SC Physics GA 201MC UT WOS:000080597700015 ER PT J AU Li, W Wang, DZ Lao, JY Ren, ZF Wang, JH Paranthaman, M Verebelyi, DT Christen, DK AF Li, W Wang, DZ Lao, JY Ren, ZF Wang, JH Paranthaman, M Verebelyi, DT Christen, DK TI Epitaxial superconducting Tl0.5Pb0.5Sr1.6Ba0.4Ca2Cu3O9 films on LaAlO3 by thermal spray and post-spray annealing SO SUPERCONDUCTOR SCIENCE & TECHNOLOGY LA English DT Article ID THIN-FILMS; PYROLYZED FILMS; LASER-ABLATION; TL0.78BI0.22SR1.6BA0.4CA2CU3O9-DELTA; GROWTH; TAPE; THICKNESS; ALIGNMENT; PHASE; YSZ AB A simple, low-cost and easily scalable method-thermal spray followed by post-spray annealing-has been successfully demonstrated for fabricating high-J(c) epitaxial superconducting films of TI0.5Pb0.5Sr1.6Ba0.4Ca2CU3O9 [(Tl, Pb)-1223]. The process was performed by spraying a stoichiometric solution containing Tl, Pb, Sr, Pa, Ca and Cu nitrates onto LaAlO3 substrates heated to 300-400 degrees C. Subsequently, the amorphous films were placed inside a silver containment along with two semicircular unfired pellets, and were reacted and crystallized by a thermal anneal at 870 degrees C in air. X-ray diffraction showed that the films consist mainly of c-axis aligned (Tl, Pb)-1223 phase with a small amount of (Tl, Pb)-1212 phase. X-ray phi-scans revealed very good epitaxial growth. Four-probe transport measurements on a 4 mm wide and 1.2 mu m thick film Showed a superconducting transition temperature of 106-109 K, with a zero-field critical current of 51 A at 77 K, which corresponds to a critical current density of 1.1 x 10(6) A cm(-2). C1 SUNY Buffalo, Dept Chem, Mat Synth Lab, Buffalo, NY 14260 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Ren, ZF (reprint author), SUNY Buffalo, Dept Chem, Mat Synth Lab, Buffalo, NY 14260 USA. RI Ren, Zhifeng/B-4275-2014; Paranthaman, Mariappan/N-3866-2015 OI Paranthaman, Mariappan/0000-0003-3009-8531 NR 16 TC 12 Z9 12 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0953-2048 J9 SUPERCOND SCI TECH JI Supercond. Sci. Technol. PD MAY PY 1999 VL 12 IS 5 BP L1 EP L4 DI 10.1088/0953-2048/12/5/101 PG 4 WC Physics, Applied; Physics, Condensed Matter SC Physics GA 201MC UT WOS:000080597700001 ER PT J AU Mao, GM Winokur, MJ AF Mao, GM Winokur, MJ TI A Monte Carlo study of structure and intercalation in conducting polymers SO SYNTHETIC METALS LA English DT Article; Proceedings Paper CT International Conference on Science and Technology of Synthetic Metals (ICSM 98) CY JUL 12-18, 1998 CL MONTPELLIER, FRANCE DE computer simulations; order-disorder phase transitions; polyacetylene and derivatives ID MEAN-FIELD THEORY; PHASE-TRANSITION; POLYACETYLENE AB Monte Carlo (MC) calculations have been used to model the equatorial chain packing within linear ir-conjugated polymers both before and after intercalation. These calculations employ a generalized anisotropic planar rotor (GAPR) representation of the host lattice through a model Hamiltonian, introduced previously in a mean-field theory (MFT) approach by H.-Y. Choi, A.B. Harris and E.J. Mele [Phys. Rev. B 40, 3766 (1989)], in which planar rotors (representing polymer chains) are pinned onto a rigid two-dimensional triangular lattice. Equilibrium structures and transition temperatures are in good agreement with those seen in MFT but additional MC calculations show the possible existence of commensurate phases with larger unit cells than those considered in MFT studies. C1 Argonne Natl Lab, Argonne, IL 60439 USA. Univ Wisconsin, Dept Phys, Madison, WI 53706 USA. RP Mao, GM (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Mao, Guomin/G-3933-2010 NR 5 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0379-6779 J9 SYNTHETIC MET JI Synth. Met. PD MAY PY 1999 VL 101 IS 1-3 BP 124 EP 125 DI 10.1016/S0379-6779(98)01333-2 PG 2 WC Materials Science, Multidisciplinary; Physics, Condensed Matter; Polymer Science SC Materials Science; Physics; Polymer Science GA 210JL UT WOS:000081101300066 ER PT J AU Kirova, N Brazovskii, S Bishop, AR McBranch, D Klimov, V AF Kirova, N Brazovskii, S Bishop, AR McBranch, D Klimov, V TI Excitations and optical properties of phenylene based polymers. SO SYNTHETIC METALS LA English DT Article; Proceedings Paper CT International Conference on Science and Technology of Synthetic Metals (ICSM 98) CY JUL 12-18, 1998 CL MONTPELLIER, FRANCE DE optical absorption and emission spectroscopy; photoinduced absorption spectroscopy ID CONDUCTING POLYMERS; CONJUGATED POLYMERS; ABSORPTION-SPECTRA; OLIGOMERS; EXCITONS; STATES; DYNAMICS AB A complex picture of phenylene-based polymers is developed which unifies features of band and molecular exciton models. It incorporates major experimental finding in direct and photoinduced optical absorption, stimulated photoemission and photoconductivity. We give new assignments for the most disputed features and identify new ones as edge states. We confirm a low binding energy for the principle emitting exciton and show that it dominates also in the fundamental absorption. Contradictions in the current modeling state-of-art are displayed and discussed. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87544 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. RP Kirova, N (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87544 USA. RI Brazovskii, Serguei/A-9608-2012 OI Brazovskii, Serguei/0000-0001-8147-9655 NR 22 TC 4 Z9 4 U1 0 U2 0 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0379-6779 J9 SYNTHETIC MET JI Synth. Met. PD MAY PY 1999 VL 101 IS 1-3 BP 188 EP 191 DI 10.1016/S0379-6779(98)00329-4 PG 4 WC Materials Science, Multidisciplinary; Physics, Condensed Matter; Polymer Science SC Materials Science; Physics; Polymer Science GA 210JL UT WOS:000081101300096 ER PT J AU Osterbacka, R Shkunov, M Chinn, D Wohlgenannt, M DeLong, M Viner, J Vardeny, ZV AF Osterbacka, R Shkunov, M Chinn, D Wohlgenannt, M DeLong, M Viner, J Vardeny, ZV TI Optical spectroscopies of excited states in poly(para phenylene vinylene) SO SYNTHETIC METALS LA English DT Article; Proceedings Paper CT International Conference on Science and Technology of Synthetic Metals (ICSM 98) CY JUL 12-18, 1998 CL MONTPELLIER, FRANCE DE optical spectroscopies; poly(para-phenylene vinylene); laser action; electroabsorption; higher excited states; mA(g) state ID PI-CONJUGATED POLYMERS; PHOTOCONDUCTIVITY; EFFICIENCIES AB We have applied a multitude of continuous wave and pulsed optical spectroscopies to thin films of unsubstituted poly(para-phenylene vinylene) (PPV) with photoluminescence quantum efficiency greater than or equal to 30%. Laser action in thin films, microdisks and microrings has been demonstrated. The threshold for lasing is comparable to other PPV derivatives. Electroabsorption unambiguosly shows that the mA(g), state is located at 3.4 eV. At higher photon energies no large polarizability of excited states could be found. The photoinduced absorption spectrum which contains both polaron and tripler excitations is very weak, showing a relatively defect free polymer. C1 Univ Utah, Dept Phys, Salt Lake City, UT 84112 USA. Abo Akad Univ, Dept Phys, Turku, Finland. Sandia Natl Labs, Livermore, CA 94551 USA. Graz Tech Univ, Inst Festkorperphys, Graz, Austria. RP Osterbacka, R (reprint author), Univ Utah, Dept Phys, Salt Lake City, UT 84112 USA. RI Osterbacka, Ronald/I-9161-2012 OI Osterbacka, Ronald/0000-0003-0656-2592 NR 20 TC 5 Z9 5 U1 1 U2 9 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0379-6779 J9 SYNTHETIC MET JI Synth. Met. PD MAY PY 1999 VL 101 IS 1-3 BP 226 EP 229 DI 10.1016/S0379-6779(98)00214-8 PG 4 WC Materials Science, Multidisciplinary; Physics, Condensed Matter; Polymer Science SC Materials Science; Physics; Polymer Science GA 210JL UT WOS:000081101300112 ER PT J AU Saxena, A Kress, JD Martin, RL Wang, WZ Shuai, Z Bishop, AR AF Saxena, A Kress, JD Martin, RL Wang, WZ Shuai, Z Bishop, AR TI Dynamics and role of nonadiabatic effects on nonlinear optical response of conjugated polymers SO SYNTHETIC METALS LA English DT Article; Proceedings Paper CT International Conference on Science and Technology of Synthetic Metals (ICSM 98) CY JUL 12-18, 1998 CL MONTPELLIER, FRANCE DE models of non-linear phenomena ID BREATHERS AB We investigated the effect of breather states on static polarizability (alpha) and hyperpolarizability (gamma) of finite polyenes (C24H26, C40H42) using molecular dynamics simulations. With all C-C bond and angle degrees of freedom included, we found significant enhancement in the presence of breathers. Using exact diagonalization technique we found that for specific values of materials parameters (electron-phonon coupling, etc.) quantum lattice fluctuations and disorder can also enhance optical nonlinearity. C1 Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Univ Mons, Serv Chim Mat Nouveaux, B-7000 Mons, Belgium. RP Saxena, A (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RI Shuai, Zhigang/H-5576-2011 OI Shuai, Zhigang/0000-0003-3867-2331 NR 11 TC 0 Z9 0 U1 1 U2 1 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0379-6779 J9 SYNTHETIC MET JI Synth. Met. PD MAY PY 1999 VL 101 IS 1-3 BP 257 EP 258 DI 10.1016/S0379-6779(98)01399-X PG 2 WC Materials Science, Multidisciplinary; Physics, Condensed Matter; Polymer Science SC Materials Science; Physics; Polymer Science GA 210JL UT WOS:000081101300127 ER PT J AU Kirova, N Brazovskii, S Bishop, AR AF Kirova, N Brazovskii, S Bishop, AR TI The model for optical properties of PPP-type polymers. SO SYNTHETIC METALS LA English DT Article; Proceedings Paper CT International Conference on Science and Technology of Synthetic Metals (ICSM 98) CY JUL 12-18, 1998 CL MONTPELLIER, FRANCE DE optical absorption and emission spectroscopy ID EXCITATIONS; PHENYLENE AB The recently successful model [1, 2] for optical properties of PPV based polymers is applied to the PPP family. More progress is available thanks to analytical results covering not only spectra but also the oscillator strength. We conclude similar assignments and emphasize the delocalized nature of basic features. We demonstrate the existence of different types of Coulomb excitons and their roles in the optical absorption. An important and intriguing difference compared with PPV based polymers is the level inversion for the more strongly localized interband exciton. Comparison is made to available optical and EELS data [3, 4, 5]. Our conclusions are suggestive for the future light polarized experiments. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87544 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. LD Landau Theoret Phys Inst, Moscow 117940, Russia. RP Kirova, N (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87544 USA. RI Brazovskii, Serguei/A-9608-2012 OI Brazovskii, Serguei/0000-0001-8147-9655 NR 5 TC 6 Z9 6 U1 0 U2 0 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0379-6779 J9 SYNTHETIC MET JI Synth. Met. PD MAY PY 1999 VL 101 IS 1-3 BP 271 EP 272 DI 10.1016/S0379-6779(98)00018-6 PG 2 WC Materials Science, Multidisciplinary; Physics, Condensed Matter; Polymer Science SC Materials Science; Physics; Polymer Science GA 210JL UT WOS:000081101300134 ER PT J AU Kraabel, B McBranch, D Hsieh, B Wudl, F AF Kraabel, B McBranch, D Hsieh, B Wudl, F TI Ultrafast spectroscopic holography in conjugated polymers SO SYNTHETIC METALS LA English DT Article; Proceedings Paper CT International Conference on Science and Technology of Synthetic Metals (ICSM 98) CY JUL 12-18, 1998 CL MONTPELLIER, FRANCE DE femtosecond; holography; polymer; charge transfer ID STORAGE; FILM AB We present a detailed study of femtosecond transient holography in conjugated polymers and blends, using tunable nondegenerate four-wave mixing. Combined with spectral transient absorption studies, these experiments determine the complex photoinduced index of refraction over the photon energy range from 1-2.5 eV. By performing a Kramers-Kronig transformation of the broad-band photoinduced absorption spectrum, a reliable spectrum of the diffraction efficiency can be obtained. The samples used include luminescent polymers from the poly-phenylene-vinylene (PPV) family, as well as charge transfer blends of PPV's with soluble methanofullerenes. One can achieve diffraction efficiencies on the order of one percent for a single femtosecond pulse, and by controlling the degree of charge transfer it is possible to tune the time constant over the range from 1 to 100 ps. These materials represent a potential holographic information processing density up to 12 orders of magnitude higher than other holographic nonlinear optical materials. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Xerox Corp, Webster, NY 14580 USA. Univ Calif Los Angeles, Inst Exot Mat, Los Angeles, CA 90095 USA. RP Kraabel, B (reprint author), Univ Calif Los Alamos Natl Lab, MS J-585, Los Alamos, NM 87545 USA. NR 15 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0379-6779 J9 SYNTHETIC MET JI Synth. Met. PD MAY PY 1999 VL 101 IS 1-3 BP 281 EP 284 DI 10.1016/S0379-6779(98)00370-1 PG 4 WC Materials Science, Multidisciplinary; Physics, Condensed Matter; Polymer Science SC Materials Science; Physics; Polymer Science GA 210JL UT WOS:000081101300137 ER PT J AU McBranch, DW Kraabel, B Xu, S Kohlman, RS Klimov, VI Bradley, DDC Hsieh, BR Rubner, M AF McBranch, DW Kraabel, B Xu, S Kohlman, RS Klimov, VI Bradley, DDC Hsieh, BR Rubner, M TI Signatures of excitons and polaron pairs in the femtosecond excited-state absorption spectra of phenylene-based conjugated polymers and oligomers SO SYNTHETIC METALS LA English DT Article; Proceedings Paper CT International Conference on Science and Technology of Synthetic Metals (ICSM 98) CY JUL 12-18, 1998 CL MONTPELLIER, FRANCE DE femtosecond transient absorption; conjugated polymers; photoexcitations ID POLY(P-PHENYLENEVINYLENE); RELAXATION; DYNAMICS AB We present results of broadband femtosecond transient absorption measurements in thin films of several phenylene-based pi-conjugated materials. We compare results for unsubstituted poly(phenylene vinylene) (PPV), polyflourene, and a substituted five-ring oligomer of PPV. We observe universal spectral features in all materials, implying a Common origin for the photoexcited species in all members of this family. In each material, we observe two photoinduced absorption (PA) features in the visible region in addition to a stimulated emission (SE) feature. The first PA feature shows strong dependence of the dynamics on excitation intensity, and correlates precisely with the SE feature, proving that this feature is due to the primary emissive exciton. The second PA feature shows dynamics independent of intensity. In the oligomers, this feature grows quadratically with respect to the first PA feature, as a result of nonlinear interactions of the primary excitons. In the polymers, however, the second feature grows linearly with intensity, and indicates an ultrafast decay channel to nonemissive interchain species due to defects. C1 Univ Calif Los Alamos Natl Lab, Chem Sci & Technol Div, Los Alamos, NM 87545 USA. Xerox Corp, Webster Res Ctr, Webster, NY 14580 USA. Univ Sheffield, Dept Phys, Sheffield S3 7RH, S Yorkshire, England. Univ Sheffield, Ctr Mol Mat, Sheffield S3 7RH, S Yorkshire, England. MIT, Dept Mat Sci & Engn, Cambridge, MA 02139 USA. RP McBranch, DW (reprint author), Univ Calif Los Alamos Natl Lab, Chem Sci & Technol Div, POB 1663, Los Alamos, NM 87545 USA. RI Bradley, Donal/F-6068-2011 OI Bradley, Donal/0000-0001-8713-5060 NR 12 TC 19 Z9 19 U1 0 U2 5 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0379-6779 J9 SYNTHETIC MET JI Synth. Met. PD MAY PY 1999 VL 101 IS 1-3 BP 291 EP 294 DI 10.1016/S0379-6779(98)00373-7 PG 4 WC Materials Science, Multidisciplinary; Physics, Condensed Matter; Polymer Science SC Materials Science; Physics; Polymer Science GA 210JL UT WOS:000081101300140 ER PT J AU Saxena, A Brazovskii, S Kirova, N Yu, ZG Bishop, AR AF Saxena, A Brazovskii, S Kirova, N Yu, ZG Bishop, AR TI Stability of bipolarons in conjugated polymers SO SYNTHETIC METALS LA English DT Article; Proceedings Paper CT International Conference on Science and Technology of Synthetic Metals (ICSM 98) CY JUL 12-18, 1998 CL MONTPELLIER, FRANCE DE many-body and quasi-particle theories AB Mie study the stability of a bipolaron as a function of the strength of the Coulomb interaction in conjugated polymers. While strong Coulomb interactions will destabilize the bipolaron, we find impurities and image forces tend to stabilize it, which implies that bipolarons may be important for charge injection at polymer-metal interfaces in the organic LEDs. C1 Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Saxena, A (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RI Yu, Z/B-5547-2009; Brazovskii, Serguei/A-9608-2012 OI Brazovskii, Serguei/0000-0001-8147-9655 NR 4 TC 16 Z9 16 U1 0 U2 5 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0379-6779 J9 SYNTHETIC MET JI Synth. Met. PD MAY PY 1999 VL 101 IS 1-3 BP 325 EP 326 DI 10.1016/S0379-6779(98)01243-0 PG 2 WC Materials Science, Multidisciplinary; Physics, Condensed Matter; Polymer Science SC Materials Science; Physics; Polymer Science GA 210JL UT WOS:000081101300157 ER PT J AU Yang, D Mattes, BR AF Yang, D Mattes, BR TI Investigation of gel inhibitor assisted dissolution of polyaniline: A case study for emeraldine base, 2-methyl-aziridine, and N-methyl-pyrrolidone SO SYNTHETIC METALS LA English DT Article; Proceedings Paper CT International Conference on Science and Technology of Synthetic Metals (ICSM 98) CY JUL 12-18, 1998 CL MONTPELLIER, FRANCE DE polyaniline; solution processing; sol-gel methods; solid-liquid phase transitions; films; fibers AB The secondary amine 2-methylaziridine (2MA) is used as an additive together with N-methyl-2-pyrrolidone (NMP), to inhibit the gel formati of highly concentrated high molecular weight solutions of polyaniline (PANi) in the emeraldine base (EB) oxidation state for up to 29 hours room temperature. Rheological properties of concentrated EB (similar to 20 wt%) solutions are studied by means of rotational viscometry as function of 2MA/EB molar ratio, time, shear rate, and temperature. Due to the formations of hydrogen bonds between the amine proton of 2MA and t lone electron pair from the imine nitrogens in the EB repeat unit. 2MA and NMP prevents the interactions between polymer chains which le; to enhanced solubility, dramatic prolongation of times to gelation, and reductions in initial solution viscosity. The temperature effects on t gelation time and the activation energy for viscous flow are reported. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Yang, D (reprint author), Univ Calif Los Alamos Natl Lab, CST-6,MJ 963, Los Alamos, NM 87545 USA. NR 8 TC 21 Z9 22 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 MAY PY 1999 VL 101 IS 1-3 BP 746 EP 749 DI 10.1016/S0379-6779(98)00225-2 PG 4 WC Materials Science, Multidisciplinary; Physics, Condensed Matter; Polymer Science SC Materials Science; Physics; Polymer Science GA 210JL UT WOS:000081101300360 ER PT J AU Nick, G Jussila, M Hoste, B Niemi, RM Kaijalainen, S de Lajudie, P Gillis, M de Bruijn, FJ Lindstrom, K AF Nick, G Jussila, M Hoste, B Niemi, RM Kaijalainen, S de Lajudie, P Gillis, M de Bruijn, FJ Lindstrom, K TI Rhizobia isolated from root nodules of tropical leguminous trees characterized using DNA-DNA dot-blot hybridisation and rep-PCR genomic fingerprinting SO SYSTEMATIC AND APPLIED MICROBIOLOGY LA English DT Article DE DNA-DNA dot-blot hybridisation; DNA-DNA reassociation; fast-growing rhizobia; Sinorhizobium; principal component analysis; rep-PCR genomic fingerprinting ID POLYMERASE CHAIN-REACTION; LENGTH-POLYMORPHISM ANALYSIS; REPETITIVE SEQUENCES; BACTERIA; STRAINS; SOIL; CLASSIFICATION; REASSOCIATION; DIVERSITY AB Fifty-one fast growing rhizobial strains isolated from root nodules of Acacia senegal and Prosopis chilensis in Sudan and Kenya were divided into DNA homology groups using non-radioactive DNA-DNA dot-blot hybridisation. Rhizobium leguminosarum, R. galegae, R. tropici, Mesorhizobium loti, Sinorhizobium fredii, S. meliloti used in numerical taxonomy were included in the hybridisation experiments as reference strains and, at a later stage S. saheli and S. terangae. Scores given to the intensities of dots detected in the hybridisation experiments were used in principal component analysis, which clustered the majority of the tree rhizobia in two separate DNA-homology groups. The 51 strains were also analysed by genomic fingerprinting using the repetitive sequence-based polymerase chain reaction (rep-PCR) method with REP, ERIC, BOX and GTG5 primers. The resulting genomic fingerprints were compared with strains representing 15 rhizobial species. The relationship of 17 Sudanese strains to established sinorhizobial species was examined using the optical renaturation rates method and the G+C content of nine strains was determined. Results from dot-blot hybridisation and rep-PCR experiments were found to be in close agreement with each other and with the results obtained from spectrophotometric reassociation analysis. We suggest that rep-PCR fingerprinting can be used as a first and dot-blot hy bridisation as a second rapid and dependable genomic screening method to classify new rhizobial isolates of unknown taxonomic status and to choose the representative strains for the more laborious DNA-DNA reassociation experiments. C1 Univ Helsinki, Dept Appl Chem & Microbiol, FIN-00014 Helsinki, Finland. State Univ Ghent, Microbiol Lab, B-9000 Ghent, Belgium. Finnish Environm Inst, Helsinki, Finland. Lab Microbiol Sols, Dakar, Senegal. Michigan State Univ, MSU, DOE, Plant Res Lab, E Lansing, MI 48824 USA. Michigan State Univ, Dept Microbiol, E Lansing, MI 48824 USA. RP Nick, G (reprint author), VTT Biotechnol & Food Res, POB 1501, VTT 02044, Finland. RI de Lajudie, Philippe/B-7460-2008 NR 34 TC 51 Z9 54 U1 2 U2 11 PU GUSTAV FISCHER VERLAG PI JENA PA VILLENGANG 2, D-07745 JENA, GERMANY SN 0723-2020 J9 SYST APPL MICROBIOL JI Syst. Appl. Microbiol. PD MAY PY 1999 VL 22 IS 2 BP 287 EP 299 PG 13 WC Biotechnology & Applied Microbiology; Microbiology SC Biotechnology & Applied Microbiology; Microbiology GA 208PZ UT WOS:000081001700016 ER PT J AU Kuske, CR Busch, JD Adorada, DL Dunbar, JM Barns, SM AF Kuske, CR Busch, JD Adorada, DL Dunbar, JM Barns, SM TI Phylogeny ribosomal RNA gene typing and relative abundance of new Pseudomonas species (sensu stricto) isolated from two pinyon-juniper woodland soils of the arid southwest US SO SYSTEMATIC AND APPLIED MICROBIOLOGY LA English DT Article DE Pseudomonas phylogeny; 16S ribosomal RNA gene; rhizosphere bacteria; soil bacteria; PCR typing ID FLUORESCENT PSEUDOMONADS; PLANT-PATHOGENS; RHIZOSPHERE; SUPPRESSION; DIVERSITY; SEQUENCES; BACTERIA; DNA; 2,4-DIACETYLPHLOROGLUCINOL; MYCORRHIZOSPHERE AB Rhizosphere-inhabiting Pseudomonas species interact with plant roots and may be important for plant performance under stressful environmental conditions. A comparison was conducted of culturable Pseudomonas isolates associated with pinyon rhizosphere and between-tree interspace areas in a hot, dry, volcanic cinder field and an adjacent sandy loam soil, in order to identify Pseudomonas species which may be involved in pinyon pine survival under stressful conditions. From a collection of 800 isolates, eleven isolates exhibiting different colony morphology were selected for 16S ribosomal RNA gene sequencing. Phylogenetic analysis of rDNA sequences from the eleven field isolates, forty-six described Pseudomonas species, and thirty-four previously characterized environmental isolates indicated that the isolates from the cinders and sandy loam soil clustered into three groups. The field isolates were distinct from any of the named species or other environmental isolates. Oligonucleotide primer pairs that differentiated three field isolate groups were designed from the 16S rDNA sequences, and eight hundred Pseudomonas field isolates cultured from pinyon rhizospheres and interspaces in the cinders and sandy loam soils were typed into the three groups using PCR assays. The composition of Pseudomonas populations in four environments was significantly different. The relative abundance of the three rDNA-based groups appeared to be affected by both the soil type and the pinyon rhizosphere. C1 Univ Calif Los Alamos Natl Lab, Div Life Sci, Environm Mol Biol Grp, Los Alamos, NM 87545 USA. RP Kuske, CR (reprint author), Univ Calif Los Alamos Natl Lab, Div Life Sci, Environm Mol Biol Grp, Los Alamos, NM 87545 USA. NR 48 TC 16 Z9 17 U1 0 U2 1 PU GUSTAV FISCHER VERLAG PI JENA PA VILLENGANG 2, D-07745 JENA, GERMANY SN 0723-2020 J9 SYST APPL MICROBIOL JI Syst. Appl. Microbiol. PD MAY PY 1999 VL 22 IS 2 BP 300 EP 311 PG 12 WC Biotechnology & Applied Microbiology; Microbiology SC Biotechnology & Applied Microbiology; Microbiology GA 208PZ UT WOS:000081001700017 PM 10390879 ER PT J AU Gupta, V AF Gupta, V TI Luddite editor? SO TECHNOLOGY REVIEW LA English DT Letter C1 Sandia Natl Labs, Livermore, CA 94550 USA. RP Gupta, V (reprint author), Sandia Natl Labs, Livermore, CA 94550 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU MASS INST TECHNOL PI CAMBRIDGE PA BUILDING W59, CAMBRIDGE, MA 02139 USA SN 0040-1692 J9 TECHNOL REV JI Technol. Rev. PD MAY-JUN PY 1999 VL 102 IS 3 BP 15 EP 15 PG 1 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 190ME UT WOS:000079966200003 ER PT J AU Bucher, JR Hailey, JR Roycroft, JR Haseman, JK Sills, RC Grumbein, SL Mellick, PW Chou, BJ AF Bucher, JR Hailey, JR Roycroft, JR Haseman, JK Sills, RC Grumbein, SL Mellick, PW Chou, BJ TI Inhalation toxicity and carcinogenicity studies of cobalt sulfate SO TOXICOLOGICAL SCIENCES LA English DT Article DE cobalt sulfate; alveolar/bronchiolar neoplasms; inhalation; respiratory toxicant; adrenal pheochromocytomas; carcinogenesis; B6C3F(1); mice; F344 rats ID HARD-METAL WORKERS; ANIMAL CARCINOGENICITY; B6C3F1 MICE; MORTALITY; EXPOSURE; INHIBITION; PROGRAM; COHORT; RATS AB Cobalt sulfate is a water-soluble cobalt salt with a variety of industrial and agricultural uses. Several cobalt compounds have induced sarcomas at injection sites in animals, and reports have suggested that exposure to cobalt-containing materials may cause lung cancer in humans. The present studies were done because no adequate rodent carcinogenicity studies had been performed with a soluble cobalt salt using a route relevant to occupational exposures. Groups of 50 male and 50 female F344/N rats and B6C3F(1) mice were exposed to aerosols containing 0, 0.3, 1.0, or 3.0 mg/m(3) cobalt sulfate hexahydrate, 6 h/day, 5 days/week, for 104 weeks. Survival and body weights of exposed rats and mice were generally unaffected by the exposures. In rats, proteinosis, alveolar epithelial metaplasia, granulomatous alveolar inflammation, and interstitial fibrosis were observed in the lung in all exposed groups. Nonneoplastic lesions of the nose and larynx were also attributed to exposure to all concentrations of cobalt sulfate. In 3.0 mg/m(3) male rats and in female rats exposed to 1.0 or 3.0 mg/m3, the incidences of alveolar/bronchiolar neoplasms were increased over those in the control groups. Lung tumors occurred with significant positive trends in both sexes. The incidences of adrenal pheochromocytoma in 1.0 mg/m3 male rats and in 3.0 mg/m3 female rats were increased. Nonneoplastic lesions of the respiratory tract were less severe in mice than in rats. In mice, alveolar/bronchiolar neoplasms in 3.0 mg/m3 males and females were greater than those in the controls, and lung tumors occurred with significantly positive trends. Male mice had liver lesions consistent with a Helicobacter hepaticus infection. Incidences of liver hemangiosarcomas were increased in exposed groups of male mice; however, because of the infection, no conclusion could be reached concerning an association between liver hemangiosarcomas and cobalt sulfate. In summary, exposure to cobalt sulfate by inhalation resulted in increased incidence of alveolar/bronchiolar neoplasms and a spectrum of inflammatory, fibrotic, and proliferative lesions in the respiratory tracts of male and female rats and mice. Adrenal pheochromocytomas were increased in female rats, and possibly in male rats. C1 NIEHS, Natl Toxicol Program, Res Triangle Pk, NC 27709 USA. Pacific NW Lab, Richland, WA 99352 USA. RP Bucher, JR (reprint author), NIEHS, Natl Toxicol Program, POB 12233, Res Triangle Pk, NC 27709 USA. NR 43 TC 52 Z9 53 U1 1 U2 8 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 1096-6080 J9 TOXICOL SCI JI Toxicol. Sci. PD MAY PY 1999 VL 49 IS 1 BP 56 EP 67 DI 10.1093/toxsci/49.1.56 PG 12 WC Toxicology SC Toxicology GA 251PX UT WOS:000083455000007 PM 10367342 ER PT J AU Katsevich, AI AF Katsevich, AI TI Local tomography with nonsmooth attenuation SO TRANSACTIONS OF THE AMERICAN MATHEMATICAL SOCIETY LA English DT Article ID GENERALIZED RADON-TRANSFORM; PSEUDODIFFERENTIAL-OPERATORS; INVERSION AB Local tomography for the Radon transform with nonsmooth attenuation is proposed and justified. The main theoretical tool is analysis of singularities of pseudodifferential operators with nonsmooth symbols. Results of numerical testing of local tomography are presented. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Katsevich, AI (reprint author), Univ Cent Florida, Dept Math, Orlando, FL 32816 USA. NR 34 TC 4 Z9 4 U1 0 U2 0 PU AMER MATHEMATICAL SOC PI PROVIDENCE PA 201 CHARLES ST, PROVIDENCE, RI 02940-2213 USA SN 0002-9947 J9 T AM MATH SOC JI Trans. Am. Math. Soc. PD MAY PY 1999 VL 351 IS 5 BP 1947 EP 1974 DI 10.1090/S0002-9947-99-02160-1 PG 28 WC Mathematics SC Mathematics GA 186UV UT WOS:000079749300010 ER PT J AU McLeod, KW McCarron, JK Conner, WH AF McLeod, KW McCarron, JK Conner, WH TI Photosynthesis and water relations of four oak species: impact of flooding and salinity SO TREES-STRUCTURE AND FUNCTION LA English DT Article DE inundation; salt tolerance; photosynthesis; conductance; water relations ID TAXODIUM-DISTICHUM; FRAXINUS-PENNSYLVANICA; SOUTH-CAROLINA; SEEDLINGS; GROWTH; SURVIVAL; BALDCYPRESS; RESPONSES; STRESS; TERM AB As global climate changes, sea level rise and increased frequency of hurricanes will expose coastal forests to increased flooding and salinity. Quercus species are frequently dominant in these forest, yet little is known about their salinity tolerance, especially in combination with flooding. III this study, 1-year-old seedlings of Quercus lyrata Walt. (overcup oak), Q. michauxii Nutt. (swamp chestnut oak), Q. nigra L. (water oaf;), and Q. nuttallii Palmer (Nuttall oak) were chronically (simulating sea level rise) and acutely (simulating hurricane storm surge) exposed to increased flooding and salinity, individually and in combination. The four species demonstrated two response patterns of photosynthesis (A), conductance, and leaf water potential, apparently related to their relative flood tolerance. In Q. lyrata, Q. nuttallii, and Q. nigra (moderately flood-tolerant), A was not immediately reduced after the initiation of the freshwater flooding, but was reduced as the duration of flooding increased. In the second pattern, demonstrated by the weakly flood-tolerant Q. michauxii, A was immediately reduced by freshwater flooding with an increasing impact over time. Watering with 2 parts per thousand (ppt) saline water did not consistently reduce A, but flooding with 2 ppt reduced A of all species, similar to the response with freshwater flooding. Photosynthesis of all species was reduced by 6 pot watering or flooding, with the latter treatment killing all species within 8 weeks. When acutely exposed to 30 ppt salinity, A was quickly and severely reduced regardless of whether the seedlings were watered or flooded. Acutely flooded seedlings ex-posed to high salinity died within 2 weeks, but seedlings watered with 30 ppt saline water recovered and A was not reduced the following spring. As saline flooding of coastal areas increases due to sea level rise, photosynthesis of these species will be differentially affected based primarily on their flood tolerance. This suggests that increased flooding associated with sea level rise will impact these tree species to a greater extent than small increases in soil salinity. High salinity accompanying storm surges will be very harmful to all of these species. C1 Univ Georgia, Savannah River Ecol Lab, Aiken, SC 29802 USA. RP McLeod, KW (reprint author), Univ Georgia, Savannah River Ecol Lab, PO Drawer E, Aiken, SC 29802 USA. EM McLeod@srel.edu NR 43 TC 11 Z9 15 U1 4 U2 26 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0931-1890 J9 TREES-STRUCT FUNCT JI Trees-Struct. Funct. PD MAY PY 1999 VL 13 IS 4 BP 178 EP 187 DI 10.1007/s004680050231 PG 10 WC Forestry SC Forestry GA 213HY UT WOS:000081267700002 ER PT J AU Moronne, MM AF Moronne, MM TI Development of X-ray excitable luminescent probes for scanning X-ray microscopy SO ULTRAMICROSCOPY LA English DT Article DE X-ray microscopy; fluorescent probes; lanthanides ID TIME-RESOLVED FLUORESCENCE; TRANSMISSION; CHELATE; LABEL AB Transmission soft X-ray microscopy is now capable of achieving resolutions that are typically 5 times better than the best-visible light microscopes. With expected improvements in zone plate optics, an additional factor of two may be realized within the next few years. Despite the high resolution now available With X-ray microscopes and the high X-ray contrast provided by biological molecules in the soft X-ray region (lambda = 2-5 nm), molecular probes for localizing specific biological targets have been lacking. To circumvent this problem, X-ray excitable molecular probes are needed that can target unique biological features. In this paper we report our initial results on the development of lanthanide-based fluorescent probes for biological labeling. Using scanning luminescence X-ray microscopy (SLXM, Jacobsen et al., J. Microscopy 172 (1993) 121-129), we show that lanthanide organo-polychelate complexes are sufficiently bright and radiation resistant to be the basis of a new class of X-ray excitable molecular probes capable of providing at least a fivefold improvement in resolution over visible light microscopy. Lanthanide probes, able to bind 80-100 metal ions per molecule, were found to give strong luminescent signals with X-ray doses exceeding 10(8) Gy, and were used to label actin stress fibers and in vitro preparations of polymerized tubulin. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, Innovat Microscopies Grp, Berkeley, CA 94720 USA. RP Moronne, MM (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, Innovat Microscopies Grp, 1 Cyclotron Rd,M-S 6-2100, Berkeley, CA 94720 USA. NR 19 TC 23 Z9 23 U1 0 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-3991 J9 ULTRAMICROSCOPY JI Ultramicroscopy PD MAY PY 1999 VL 77 IS 1-2 BP 23 EP 36 DI 10.1016/S0304-3991(99)00002-9 PG 14 WC Microscopy SC Microscopy GA 191HR UT WOS:000080017500003 PM 10321038 ER PT J AU Hseuh, HC Davis, R Pate, D Smart, L Todd, R Weiss, D AF Hseuh, HC Davis, R Pate, D Smart, L Todd, R Weiss, D TI RHIC vacuum systems SO VACUUM LA English DT Article; Proceedings Paper CT 14th International Vacuum Congress/10th International Conference on Solid Surfaces/5th International Conference on Nanometre-Scale Science and Technology/10th International Conference on Quantitative Surface Analysis CY AUG 31-SEP 04, 1998 CL BIRMINGHAM, ENGLAND SP British Vacuum Council, Inst Phys, Int Union Vacuum Sci Tech & Applicat ID HELIUM; LONG AB The relativistic heavy ion collider (RHIC), presently under construction at Brookhaven, has two concentric rings 3.8 km in circumference. There are three distinct vacuum systems in RHIC. The design of these three vacuum systems is presented. The measurement of helium travel within the 480 m cold bore beam tube and the method of locating helium leaks in the long cryostat are also presented. (C) 1999 Elsevier Science Ltd. All rights reserved. C1 Brookhaven Natl Lab, RHIC Project, Upton, NY 11973 USA. RP Hseuh, HC (reprint author), Brookhaven Natl Lab, RHIC Project, Upton, NY 11973 USA. NR 3 TC 4 Z9 4 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0042-207X J9 VACUUM JI Vacuum PD MAY PY 1999 VL 53 IS 1-2 BP 347 EP 352 DI 10.1016/S0042-207X(98)00368-6 PG 6 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA 181YG UT WOS:000079470600073 ER PT J AU Walvoord, MA Pegram, P Phillips, FM Person, M Kieft, TL Frederickson, JK McKinley, JP Swenson, JB AF Walvoord, MA Pegram, P Phillips, FM Person, M Kieft, TL Frederickson, JK McKinley, JP Swenson, JB TI Groundwater flow and geochemistry in the southeastern San Juan Basin: Implications for microbial transport and activity SO WATER RESOURCES RESEARCH LA English DT Article ID VARIABLE-DENSITY GROUNDWATER; NEW-MEXICO; SUBSURFACE SEDIMENTS; HETEROTROPHIC BACTERIA; TERRESTRIAL SUBSURFACE; ISOTOPE GEOCHEMISTRY; DEEP; AQUIFER; ENVIRONMENTS; CONSTRAINTS AB Recent confirmation of widespread microbial activity in the deep subsurface has raised the question whether microbes were transported to their current residence from the surface or whether they have survived in situ since sediment deposition. As a part of a larger study addressing these and related questions, we have characterized the microbiology and hydrogeology of a Late Cretaceous sandstone and shale sequence in the southeastern San Juan Basin, New Mexico, near a 3.39 Ma volcanic intrusion. Deep core samples were analyzed for microbial activity to assess recolonization of the previously sterilized zone around the intrusion. Groundwater geochemistry and isotopic data were used to improve the understanding of the flow regime. We modeled the geochemical evolution of the groundwater from the recharge area to each sample location and used the resultant mass transfers to correct measured C-14 activities. The C-14 ages provided the basis for calibrating a cross-sectional flow model that intersects the intrusion. Based on microbial activity data, hydrogeologic modeling results supported the inference that groundwater velocities were adequate to transport microbes into the previously sterilized region in the time since the volcanic intrusion. Evidence of upward groundwater flow near the intrusion and high vertical hydraulic conductivities for shale suggest considerable hydraulic connection between lithologic units, which may influence the nutrient distribution and promote enhanced microbial activity near lithologic interfaces. C1 New Mexico Inst Min & Technol, Dept Earth & Environm Sci, Socorro, NM 87801 USA. Univ Minnesota, Dept Geol & Geophys, Minneapolis, MN 55455 USA. New Mexico Inst Min & Technol, Dept Earth & Environm Sci, Socorro, NM 87801 USA. Pacific NW Lab, Richland, WA 99352 USA. RP Walvoord, MA (reprint author), New Mexico Inst Min & Technol, Dept Earth & Environm Sci, Socorro, NM 87801 USA. EM mwalvoor@nmt.edu NR 52 TC 16 Z9 17 U1 2 U2 10 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 MAY PY 1999 VL 35 IS 5 BP 1409 EP 1424 DI 10.1029/1999WR900017 PG 16 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA 190YG UT WOS:000079992400007 ER PT J AU Ennis, CJ Morton, SA Sun, L Tear, SP McCash, EM AF Ennis, CJ Morton, SA Sun, L Tear, SP McCash, EM TI Silane adsorption on Pd(100) - a low-temperature RAIRS study SO CHEMICAL PHYSICS LETTERS LA English DT Article ID SURFACE AB Silane adsorption and reaction on Pd(100) have been investigated between 23-80 K by reflection-absorption infrared spectroscopy (RAIRS). Exposure to a silane/argon mixture at a substrate temperature of 23 K results in physisorbed islands of silane with argon matrix isolated silane in subsequent layers. At a substrate temperature of 70 K the silane forms a uniform physisorbed layer on the surface which undergoes dissociative chemisorption at similar to 78 K. On Pd(100) a surface stabilised SIH moiety is formed; direct adsorption at 80 K leads to the formation of islands of SiH with overlayers of physisorbed molecular silane. The SiH species is stable to 200 K at which point complete dissociation occurs. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Univ York, Dept Chem, York YO10 5DD, N Yorkshire, England. Univ York, Dept Phys, York YO10 5DD, N Yorkshire, England. Lawrence Berkeley Natl Lab MS 7222, Berkeley, CA 94720 USA. RP McCash, EM (reprint author), Univ York, Dept Chem, York YO10 5DD, N Yorkshire, England. NR 19 TC 8 Z9 8 U1 0 U2 0 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 APR 30 PY 1999 VL 304 IS 3-4 BP 217 EP 224 DI 10.1016/S0009-2614(99)00321-8 PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 191QE UT WOS:000080032400015 ER PT J AU Orel, AE Kuhn, O AF Orel, AE Kuhn, O TI Cartesian reaction surface analysis of the CH2I2 ground state isomerization SO CHEMICAL PHYSICS LETTERS LA English DT Article ID PATH; DIHALOMETHANES; SPECTROSCOPY; DIFFUSION; MOLECULES; HYDROGEN AB We report the two-dimensional Cartesian reaction potential energy surface for the isomerization reaction of CH2I2 from diiodomethane to isodiiodomethane. In this surface the frame of the substrate CH2I is fixed and only the active iodine is allowed to move. The normal modes of the substrate atoms are analyzed and the reorganization energy is calculated. The results are compared with the minimum energy path for the isomerization on the fully relaxed potential surface. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Free Univ Berlin, Inst Phys & Theoret Chem, D-14195 Berlin, Germany. Univ Calif Lawrence Livermore Natl Lab, Dept Appl Sci, Livermore, CA 94550 USA. RP Orel, AE (reprint author), Free Univ Berlin, Inst Phys & Theoret Chem, Takustr 3, D-14195 Berlin, Germany. RI Kuhn, Oliver/J-8808-2012 OI Kuhn, Oliver/0000-0002-5132-2961 NR 20 TC 19 Z9 19 U1 0 U2 0 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 APR 30 PY 1999 VL 304 IS 3-4 BP 285 EP 292 DI 10.1016/S0009-2614(99)00298-5 PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 191QE UT WOS:000080032400025 ER PT J AU Key, SW Heinstein, MW Stone, CM Mello, FJ Blanford, ML Budge, KG AF Key, SW Heinstein, MW Stone, CM Mello, FJ Blanford, ML Budge, KG TI A suitable low-order, tetrahedral finite element for solids SO INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING LA English DT Article DE solid finite element; tetrahedral finite element; hourglass control; lumped mass; transient dynamics ID UNIFORM STRAIN HEXAHEDRON AB To use the all-tetrahedral mesh generation capabilities existing today, we have explored the creation of a computationally efficient eight-node tetrahedral finite element (a four-node tetrahedral finite element enriched with four mid-face nodal points). The derivation of the element's gradient operator, studies in obtaining a suitable mass lumping and the element's performance in applications are presented. In particular, we examine the eight-node tetrahedral finite element's behavior in longitudinal plane wave propagation, in transverse cylindrical wave propagation, and in simulating Taylor bar impacts. The element samples only constant strain states and, therefore, has 12 hourglass modes. In this regard, it bears similarities to the eight-node, mean-quadrature hexahedral finite element. Comparisons with the results obtained from the mean-quadrature eight-node hexahedral finite element and the four-node tetrahedral finite element are included. Given automatic all-tetrahedral meshing, the eight-node, mean-quadrature tetrahedral finite element is a suitable replacement for the eight-node, mean-quadrature hexahedral finite element and meshes requiring an inordinate amount of user intervention and direction to generate. Copyright (C) 1999 John Wiley & Sons, Ltd. This paper was produced under the auspices of the U.S. Government and it is therefore not subject to copyright in the U.S. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Key, SW (reprint author), Sandia Natl Labs, Mailstop 0443, Albuquerque, NM 87185 USA. NR 18 TC 7 Z9 8 U1 0 U2 6 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 0029-5981 J9 INT J NUMER METH ENG JI Int. J. Numer. Methods Eng. PD APR 30 PY 1999 VL 44 IS 12 BP 1785 EP 1805 DI 10.1002/(SICI)1097-0207(19990430)44:12<1785::AID-NME561>3.0.CO;2-5 PG 21 WC Engineering, Multidisciplinary; Mathematics, Interdisciplinary Applications SC Engineering; Mathematics GA 182DJ UT WOS:000079483000002 ER PT J AU Dohrmann, CR Key, SW AF Dohrmann, CR Key, SW TI A transition element for uniform strain hexahedral and tetrahedral finite elements SO INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING LA English DT Article DE finite elements; transition element; uniform strain; hourglass control AB A transition element is presented for meshes containing uniform strain hexahedral and tetrahedral finite elements. It is shown that the volume of the standard uniform strain hexahedron is identical to that of a polyhedron with 14 vertices and 24 triangular faces. Based on this equivalence, a transition element is developed as a simple modification of the uniform strain hexahedron. The transition element makes use of a general method for hourglass control and satisfies first-order patch tests. Example problems in linear elasticity are included to demonstrate the application of the element. Copyright (C) 1999 John Wiley & Sons, Ltd. C1 Sandia Natl Labs, Struct Dynam Dept, Albuquerque, NM 87185 USA. Sandia Natl Labs, Dept Mech & Mfg Engn, Albuquerque, NM 87185 USA. RP Dohrmann, CR (reprint author), Sandia Natl Labs, Struct Dynam Dept, Mailstop 0439,MS 0439, Albuquerque, NM 87185 USA. NR 7 TC 15 Z9 15 U1 0 U2 1 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 0029-5981 J9 INT J NUMER METH ENG JI Int. J. Numer. Methods Eng. PD APR 30 PY 1999 VL 44 IS 12 BP 1933 EP 1950 DI 10.1002/(SICI)1097-0207(19990430)44:12<1933::AID-NME574>3.0.CO;2-0 PG 18 WC Engineering, Multidisciplinary; Mathematics, Interdisciplinary Applications SC Engineering; Mathematics GA 182DJ UT WOS:000079483000009 ER PT J AU Chen, G Yuan, SSF Liu, W Xu, Y Trujillo, K Song, BW Cong, F Goff, SP Wu, Y Arlinghaus, R Baltimore, D Gasser, PJ Park, MS Sung, P Lee, EYHP AF Chen, G Yuan, SSF Liu, W Xu, Y Trujillo, K Song, BW Cong, F Goff, SP Wu, Y Arlinghaus, R Baltimore, D Gasser, PJ Park, MS Sung, P Lee, EYHP TI Radiation-induced assembly of Rad51 and Rad52 recombination complex requires ATM and c-Abl SO JOURNAL OF BIOLOGICAL CHEMISTRY LA English DT Article ID REPLICATION PROTEIN-A; DOUBLE-STRAND BREAKS; ATAXIA-TELANGIECTASIA CELLS; DNA-DAMAGE; HOMOLOGOUS RECOMBINATION; IONIZING-RADIATION; TYROSINE KINASE; GENE-PRODUCT; REPAIR; PHOSPHORYLATION AB Cells from individuals with the recessive cancer-prone disorder ataxia telangiectasia (A-T) are hypersensitive to ionizing radiation (I-R). ATM (mutated in A-T) is a protein kinase whose activity is stimulated by I-R. c-Abl, a nonreceptor tyrosine kinase, interacts with ATM and is activated by ATM following I-R. Rad51 is a homologue of bacterial RecA protein required for DNA recombination and repair. Here we demonstrate that there is an I-R-induced Rad51 tyrosine phosphorylation, and this induction is dependent on both ATM and c-Abl. ATM, c-Abl, and Rad51 can be co-immunoprecipitated from cell extracts. Consistent with the physical interaction, c-Abl phosphorylates Rad51 in vitro and in vivo. In assays using purified components, phosphorylation of Rad51 by c-Abl enhances complex formation between Rad51 and Rad52, which cooperates with Rad51 in recombination and repair. After I-R, an increase in association between Rad51 and Rad52 occurs in wild-type cells but not in cells with mutations that compromise ATM or c-Abl. Our data suggest signaling mediated through ATM, and c-Abl is required for the correct posttranslational modification of Rad51, which is critical for the assembly of Rad51 repair protein complex following I-R. C1 Univ Texas, Hlth Sci Ctr, Inst Biotechnol, Dept Mol Med, San Antonio, TX 78245 USA. MIT, Dept Biol, Cambridge, MA 02139 USA. Columbia Univ, Howard Hughes Med Inst, Dept Biochem & Mol Biophys, New York, NY 10032 USA. Univ Texas, MD Anderson Cancer Ctr, Dept Mol Pathol, Houston, TX 77030 USA. Univ Calif Los Alamos Natl Lab, Div Life Sci, Los Alamos, NM 87545 USA. RP Lee, EYHP (reprint author), Univ Texas, Hlth Sci Ctr, Inst Biotechnol, Dept Mol Med, 7703 Floyd Curl Dr, San Antonio, TX 78245 USA. RI Goff, Stephen/K-6337-2014; OI Goff, Stephen/0000-0003-0693-5547; Gasser, Paul/0000-0002-2092-6068 FU NINDS NIH HHS [1RO1NS378381-01] NR 40 TC 199 Z9 204 U1 1 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 APR 30 PY 1999 VL 274 IS 18 BP 12748 EP 12752 DI 10.1074/jbc.274.18.12748 PG 5 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 192BC UT WOS:000080056800078 PM 10212258 ER PT J AU Li, J Fritz, JS AF Li, J Fritz, JS TI Separation of anilines by capillary electrophoresis with small ionic compounds as buffer additives SO JOURNAL OF CHROMATOGRAPHY A LA English DT Article DE background electrolyte composition; anilines ID MICELLAR ELECTROKINETIC CHROMATOGRAPHY; FUSED-SILICA CAPILLARIES; BETA-CYCLODEXTRIN; SUBSTITUTED ANILINES; ZONE ELECTROPHORESIS; MIGRATION BEHAVIOR; BASIC-PROTEINS; MOBILE PHASE; LOW PH; CHLOROANILINES AB Addition of either ethanesulfonic acid or protonated triethylamine to the background electrolyte was found to markedly improve the separation of protonated anilines by capillary electrophoresis. These additives appear to form a thin coating on the capillary surface via a dynamic equilibrium. This results in a change in electroosmotic flow and reduces interactions of the sample cations with the silica surface. A mixture of 10 substituted anilines could be separated, including several positional isomers. Migration times of the sample cations were reproducible with a RSD less than 1.0%. (C) 1999 Elsevier Science B.V. All rights reserved. C1 US DOE, Ames Lab, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Dept Chem, Ames, IA 50011 USA. RP Fritz, JS (reprint author), US DOE, Ames Lab, Ames, IA 50011 USA. NR 30 TC 14 Z9 14 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0021-9673 J9 J CHROMATOGR A JI J. Chromatogr. A PD APR 30 PY 1999 VL 840 IS 2 BP 269 EP 279 DI 10.1016/S0021-9673(99)00239-3 PG 11 WC Biochemical Research Methods; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA 193XF UT WOS:000080162500012 ER PT J AU Maroney, MJ Choudhury, SB Lee, JW Davidson, G Yim, YI Bose, K Sharma, ML Kang, SO Cabelli, DE AF Maroney, MJ Choudhury, SB Lee, JW Davidson, G Yim, YI Bose, K Sharma, ML Kang, SO Cabelli, DE TI A SOD story: The structure and function of the NiSOD active site SO JOURNAL OF INORGANIC BIOCHEMISTRY LA English DT Meeting Abstract C1 Univ Massachusetts, Dept Chem, Amherst, MA 01003 USA. Univ Massachusetts, Program Mol & Cellular Biol, Amherst, MA 01003 USA. Seoul Natl Univ, Coll Nat Sci, Dept Microbiol, Biophys Lab, Seoul 151742, South Korea. Seoul Natl Univ, Res Ctr Mol Microbiol, Seoul 151742, South Korea. Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0162-0134 J9 J INORG BIOCHEM JI J. Inorg. Biochem. PD APR 30 PY 1999 VL 74 IS 1-4 BP 39 EP 39 PG 1 WC Biochemistry & Molecular Biology; Chemistry, Inorganic & Nuclear SC Biochemistry & Molecular Biology; Chemistry GA 211JP UT WOS:000081157700070 ER PT J AU Schlichting, I Berendzen, J Chu, K Stock, AM Sweet, RM Ringe, D Petsko, GA Davies, M Gerber, NC Mueller, EJ Benson, D Vidakovic, M Sligar, SG AF Schlichting, I Berendzen, J Chu, K Stock, AM Sweet, RM Ringe, D Petsko, GA Davies, M Gerber, NC Mueller, EJ Benson, D Vidakovic, M Sligar, SG TI Crystal structures of intermediates occurring along the reaction coordinate of cytochrome P450(cam) SO JOURNAL OF INORGANIC BIOCHEMISTRY LA English DT Meeting Abstract C1 Max Planck Inst, Dortmund, Germany. Univ Calif Los Alamos Natl Lab, Biophys Grp, Los Alamos, NM 87545 USA. Rutgers State Univ, CABM, Piscataway, NJ 08855 USA. Brookhaven Natl Lab, Dept Biol, Upton, NY 11973 USA. Brandeis Univ, Rosenstiel Ctr, Waltham, MA 02254 USA. Univ Illinois, Beckman Inst Adv Sci & Technol, Chicago, IL 60680 USA. NR 0 TC 1 Z9 1 U1 0 U2 1 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0162-0134 J9 J INORG BIOCHEM JI J. Inorg. Biochem. PD APR 30 PY 1999 VL 74 IS 1-4 BP 49 EP 49 PG 1 WC Biochemistry & Molecular Biology; Chemistry, Inorganic & Nuclear SC Biochemistry & Molecular Biology; Chemistry GA 211JP UT WOS:000081157700090 ER PT J AU Shanklin, J Whittle, E AF Shanklin, J Whittle, E TI Integral membrane diiron proteins: a distinct and widespread group of enzymes with diverse catalytic plasticity SO JOURNAL OF INORGANIC BIOCHEMISTRY LA English DT Meeting Abstract C1 Brookhaven Natl Lab, Dept Biol, Upton, NY 11973 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0162-0134 J9 J INORG BIOCHEM JI J. Inorg. Biochem. PD APR 30 PY 1999 VL 74 IS 1-4 BP 50 EP 50 PG 1 WC Biochemistry & Molecular Biology; Chemistry, Inorganic & Nuclear SC Biochemistry & Molecular Biology; Chemistry GA 211JP UT WOS:000081157700093 ER PT J AU Wang, Y Gebbink, RJMK Dubois, J Hedman, B Hodgson, K Stack, TDP AF Wang, Y Gebbink, RJMK Dubois, J Hedman, B Hodgson, K Stack, TDP TI Capturing the essence of a metalloenzyme SO JOURNAL OF INORGANIC BIOCHEMISTRY LA English DT Meeting Abstract ID GALACTOSE-OXIDASE C1 Stanford Univ, Dept Chem, Stanford, CA 94305 USA. Stanford Synchrotron Radiat Lab, Stanford, CA 94309 USA. NR 4 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 0162-0134 J9 J INORG BIOCHEM JI J. Inorg. Biochem. PD APR 30 PY 1999 VL 74 IS 1-4 BP 52 EP 52 PG 1 WC Biochemistry & Molecular Biology; Chemistry, Inorganic & Nuclear SC Biochemistry & Molecular Biology; Chemistry GA 211JP UT WOS:000081157700096 ER PT J AU Anxolabehere-Mallart, E Visser, H Bergman, U Cramer, SP Girerd, JJ Sauer, K Yachandra, VK Klein, MP AF Anxolabehere-Mallart, E Visser, H Bergman, U Cramer, SP Girerd, JJ Sauer, K Yachandra, VK Klein, MP TI MnK-edge XANES studies and high resolution MnK(beta)fluorescence spectroscopy of manganese dinuclear complexes. Investigation of three different oxidation states and relevance to the Oxygen Evolving Center of PSII. SO JOURNAL OF INORGANIC BIOCHEMISTRY LA English DT Meeting Abstract C1 Lawrence Berkeley Lab, Struct Biol Div, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Univ Paris Sud, UMR CNRS 420, Chim Inorgan Lab, F-91405 Orsay, France. Univ Calif Davis, Dept Appl Sci, Davis, CA 95616 USA. NR 0 TC 1 Z9 1 U1 0 U2 1 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0162-0134 J9 J INORG BIOCHEM JI J. Inorg. Biochem. PD APR 30 PY 1999 VL 74 IS 1-4 BP 66 EP 66 PG 1 WC Biochemistry & Molecular Biology; Chemistry, Inorganic & Nuclear SC Biochemistry & Molecular Biology; Chemistry GA 211JP UT WOS:000081157700120 ER PT J AU Pidcock, E DeBeer, S Obias, HV Hedman, B Hodgson, KO Karlin, KD Solomon, EI AF Pidcock, E DeBeer, S Obias, HV Hedman, B Hodgson, KO Karlin, KD Solomon, EI TI A study of solid [{Cu(MePY2)}(2)O-2](2+) using resonance Raman and X-ray absorption spectroscopies: an intermediate Cu2O2 core structure or a solid solution? SO JOURNAL OF INORGANIC BIOCHEMISTRY LA English DT Meeting Abstract C1 Stanford Univ, Dept Chem, Stanford, CA 94305 USA. Johns Hopkins Univ, Dept Chem, Baltimore, MD 21218 USA. Stanford Univ, Stanford Linear Accelerator Ctr, Stanford Synchrotron Radiat Lab, Stanford, CA 94309 USA. RI DeBeer, Serena/G-6718-2012 NR 0 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 0162-0134 J9 J INORG BIOCHEM JI J. Inorg. Biochem. PD APR 30 PY 1999 VL 74 IS 1-4 BP 111 EP 111 PG 1 WC Biochemistry & Molecular Biology; Chemistry, Inorganic & Nuclear SC Biochemistry & Molecular Biology; Chemistry GA 211JP UT WOS:000081157700210 ER PT J AU Franco, R Ma, JG Lu, Y Pereira, A Tavares, P Moura, I Shelnutt, JA Ferreira, GC AF Franco, R Ma, JG Lu, Y Pereira, A Tavares, P Moura, I Shelnutt, JA Ferreira, GC TI Spectroscopic characterization of porphyrin binding to ferrochelatase, the last enzyme in the heme biosynthetic pathway SO JOURNAL OF INORGANIC BIOCHEMISTRY LA English DT Meeting Abstract ID MAMMALIAN FERROCHELATASE C1 Univ Nova Lisboa, Fac Ciencias & Tecnol, Dept Quim, Ctr Quim Fina & Biotecnol, P-2825 Monte De Caparica, Portugal. Univ New Mexico, New Mat Theory & Validat Dept, Sandia Natl Labs, Albuquerque, NM 87131 USA. Univ New Mexico, Dept Chem, Albuquerque, NM 87131 USA. Univ S Florida, H Lee Moffitt Canc Ctr, Inst Biomol Sci, Coll Med,Dept Biochem & Mol Biol, Tampa, FL 33682 USA. RI Shelnutt, John/A-9987-2009; Ferreira, Gloria/A-4709-2012; Tavares, Pedro/B-3654-2008; REQUIMTE, SMB/M-5694-2013; Moura, Isabel/D-6339-2013; REQUIMTE, UCIBIO/N-9846-2013 OI Shelnutt, John/0000-0001-7368-582X; Tavares, Pedro/0000-0002-7398-2661; Moura, Isabel/0000-0003-0971-4977; NR 3 TC 0 Z9 0 U1 0 U2 1 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0162-0134 J9 J INORG BIOCHEM JI J. Inorg. Biochem. PD APR 30 PY 1999 VL 74 IS 1-4 BP 130 EP 130 PG 1 WC Biochemistry & Molecular Biology; Chemistry, Inorganic & Nuclear SC Biochemistry & Molecular Biology; Chemistry GA 211JP UT WOS:000081157700245 ER PT J AU Gavel, OY Bursakov, SA George, GN Calvete, JJ Moura, JJG Moura, I AF Gavel, OY Bursakov, SA George, GN Calvete, JJ Moura, JJG Moura, I TI Cobalt and zinc containing ATP sulfurylases from sulfate-reducing bacteria of the genus Desulfovibrio SO JOURNAL OF INORGANIC BIOCHEMISTRY LA English DT Meeting Abstract C1 Univ Nova Lisboa, Fac Ciencias & Tecnol, Dept Quim, Ctr Quim Fina & Biotecnol, P-2825 Monte De Caparica, Portugal. Stanford Univ, Stanford Linear Accelerator Ctr, Stanford Synchrotron Radiat Lab, Stanford, CA 94309 USA. CSIC, Inst Invest Biomed, Valencia, Spain. Russian Acad Sci, AN Bach Inst Biochem, Moscow 117071, Russia. RI Moura, Jose/D-6426-2013; George, Graham/E-3290-2013; REQUIMTE, SMB/M-5694-2013; Moura, Isabel/D-6339-2013; REQUIMTE, UCIBIO/N-9846-2013 OI Moura, Jose/0000-0002-4726-2388; Moura, Isabel/0000-0003-0971-4977; NR 0 TC 0 Z9 0 U1 0 U2 3 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0162-0134 J9 J INORG BIOCHEM JI J. Inorg. Biochem. PD APR 30 PY 1999 VL 74 IS 1-4 BP 137 EP 137 PG 1 WC Biochemistry & Molecular Biology; Chemistry, Inorganic & Nuclear SC Biochemistry & Molecular Biology; Chemistry GA 211JP UT WOS:000081157700257 ER PT J AU Glaser, T Rose, K Anxolabehere-Mallart, E Shadle, SE Frank, P Hedman, B Hodgson, KO Solomon, EI AF Glaser, T Rose, K Anxolabehere-Mallart, E Shadle, SE Frank, P Hedman, B Hodgson, KO Solomon, EI TI The electronic structures of iron-sulfur clusters in models and proteins studied by SK-edge XAS SO JOURNAL OF INORGANIC BIOCHEMISTRY LA English DT Meeting Abstract C1 Stanford Univ, Dept Chem, Stanford, CA 94305 USA. Stanford Univ, Stanford Linear Accelerator Ctr, Stanford Synchrotron Radiat Lab, Stanford, CA 94309 USA. RI Glaser, Thorsten/H-5187-2013 OI Glaser, Thorsten/0000-0003-2056-7701 NR 0 TC 0 Z9 0 U1 0 U2 2 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0162-0134 J9 J INORG BIOCHEM JI J. Inorg. Biochem. PD APR 30 PY 1999 VL 74 IS 1-4 BP 142 EP 142 PG 1 WC Biochemistry & Molecular Biology; Chemistry, Inorganic & Nuclear SC Biochemistry & Molecular Biology; Chemistry GA 211JP UT WOS:000081157700268 ER PT J AU Hsu, HF Que, L Shanklin, J AF Hsu, HF Que, L Shanklin, J TI XAS studies of membrane bound alkane omega-hydroxylase: Evidence for a histidine-rich ligand environment in the nonheme diiron site SO JOURNAL OF INORGANIC BIOCHEMISTRY LA English DT Meeting Abstract C1 Univ Minnesota, Dept Chem, Minneapolis, MN 55455 USA. Univ Minnesota, Ctr Met Biocatalysis, Minneapolis, MN 55455 USA. Brookhaven Natl Lab, Dept Biol, Upton, NY 11973 USA. NR 1 TC 6 Z9 6 U1 1 U2 2 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0162-0134 J9 J INORG BIOCHEM JI J. Inorg. Biochem. PD APR 30 PY 1999 VL 74 IS 1-4 BP 168 EP 168 PG 1 WC Biochemistry & Molecular Biology; Chemistry, Inorganic & Nuclear SC Biochemistry & Molecular Biology; Chemistry GA 211JP UT WOS:000081157700320 ER PT J AU Lu, Y Shelnutt, JA Ma, JG Franco, R Moura, I Moura, JJG Kroneck, PMH Chapman, SK AF Lu, Y Shelnutt, JA Ma, JG Franco, R Moura, I Moura, JJG Kroneck, PMH Chapman, SK TI Non-planar heme distortions in multiheme c-type cytochromes SO JOURNAL OF INORGANIC BIOCHEMISTRY LA English DT Meeting Abstract C1 Sandia Natl Labs, New Mat Theory & Validat Dept, Albuquerque, NM 87185 USA. Univ Nova Lisboa, Fac Ciencias & Tecnol, Dept Quim, Ctr Quim Fina & Biotecnol, P-2825 Monte De Caparica, Portugal. Univ Konstanz, Fak Biol, D-7750 Constance, Germany. Univ Edinburgh, Dept Chem, Edinburgh EH9 3JJ, Midlothian, Scotland. RI Shelnutt, John/A-9987-2009; REQUIMTE, SMB/M-5694-2013; Moura, Isabel/D-6339-2013; REQUIMTE, UCIBIO/N-9846-2013 OI Shelnutt, John/0000-0001-7368-582X; Moura, Isabel/0000-0003-0971-4977; NR 0 TC 0 Z9 0 U1 0 U2 1 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0162-0134 J9 J INORG BIOCHEM JI J. Inorg. Biochem. PD APR 30 PY 1999 VL 74 IS 1-4 BP 214 EP 214 PG 1 WC Biochemistry & Molecular Biology; Chemistry, Inorganic & Nuclear SC Biochemistry & Molecular Biology; Chemistry GA 211JP UT WOS:000081157700401 ER PT J AU Mahadevan, V DuBois, JL Hedman, B Hodgson, KO Stack, TDP AF Mahadevan, V DuBois, JL Hedman, B Hodgson, KO Stack, TDP TI Exogenous substrate reactivity with a [Cu(III)(2)O-2](2+) core: structural implications SO JOURNAL OF INORGANIC BIOCHEMISTRY LA English DT Meeting Abstract C1 Stanford Univ, Dept Chem, Stanford, CA 94305 USA. Stanford Univ, Stanford Synchrotron Radiat Lab, Stanford, CA 94309 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0162-0134 J9 J INORG BIOCHEM JI J. Inorg. Biochem. PD APR 30 PY 1999 VL 74 IS 1-4 BP 220 EP 220 PG 1 WC Biochemistry & Molecular Biology; Chemistry, Inorganic & Nuclear SC Biochemistry & Molecular Biology; Chemistry GA 211JP UT WOS:000081157700413 ER PT J AU Musgrave, KB Donahue, JP Lorber, C Holm, RH Hedman, B Hodgson, KO AF Musgrave, KB Donahue, JP Lorber, C Holm, RH Hedman, B Hodgson, KO TI An x-ray spectroscopic investigation of bis(dithiolene)-molybdenum(IV,V,VI) and tungsten (IV,V,VI) complexes: symmetrized structural representations of the active sites of molybdoenzymes in the DMSO reductase family and of tungstoenzymes in the AOR and F(M)DH families SO JOURNAL OF INORGANIC BIOCHEMISTRY LA English DT Meeting Abstract C1 Stanford Univ, Dept Chem, Stanford, CA 94305 USA. Stanford Linear Accelerator Ctr, Stanford Synchrotron Radiat Lab, Stanford, CA 94309 USA. Harvard Univ, Dept Chem & Biol Chem, Cambridge, MA 02138 USA. RI Lorber, Christian/G-5490-2012 OI Lorber, Christian/0000-0003-1361-5373 NR 0 TC 0 Z9 0 U1 0 U2 2 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0162-0134 J9 J INORG BIOCHEM JI J. Inorg. Biochem. PD APR 30 PY 1999 VL 74 IS 1-4 BP 243 EP 243 PG 1 WC Biochemistry & Molecular Biology; Chemistry, Inorganic & Nuclear SC Biochemistry & Molecular Biology; Chemistry GA 211JP UT WOS:000081157700458 ER PT J AU Robblee, JH Messinger, J Fernandez, C Cinco, RM Visser, H McFarlane, KL Bergmann, U Glatzel, P Cramer, SP Sauer, K Klein, MP AF Robblee, JH Messinger, J Fernandez, C Cinco, RM Visser, H McFarlane, KL Bergmann, U Glatzel, P Cramer, SP Sauer, K Klein, MP TI Oxidation states of the Mn cluster in the S-states of the oxygen-evolving complex of PSII SO JOURNAL OF INORGANIC BIOCHEMISTRY LA English DT Meeting Abstract C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Lawrence Berkeley Lab, Phys Biosci Div, Berkeley, CA 94720 USA. Univ Calif Davis, Dept Appl Sci, Davis, CA 95616 USA. RI Glatzel, Pieter/E-9958-2010; Institute of Chemistry - USP, Dept. of Chemistry/B-8988-2012 OI Glatzel, Pieter/0000-0001-6532-8144; NR 0 TC 1 Z9 1 U1 0 U2 1 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0162-0134 J9 J INORG BIOCHEM JI J. Inorg. Biochem. PD APR 30 PY 1999 VL 74 IS 1-4 BP 278 EP 278 PG 1 WC Biochemistry & Molecular Biology; Chemistry, Inorganic & Nuclear SC Biochemistry & Molecular Biology; Chemistry GA 211JP UT WOS:000081157700516 ER PT J AU Ruggiero, CE Neu, MP Vanderberg, LA AF Ruggiero, CE Neu, MP Vanderberg, LA TI Plutonium and uranium interactions with siderophores of aerobic soil microbes SO JOURNAL OF INORGANIC BIOCHEMISTRY LA English DT Meeting Abstract C1 Univ Calif Los Alamos Natl Lab, Chem Sci & Technol Div, Los Alamos, NM 87545 USA. NR 0 TC 3 Z9 3 U1 1 U2 2 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0162-0134 J9 J INORG BIOCHEM JI J. Inorg. Biochem. PD APR 30 PY 1999 VL 74 IS 1-4 BP 282 EP 282 PG 1 WC Biochemistry & Molecular Biology; Chemistry, Inorganic & Nuclear SC Biochemistry & Molecular Biology; Chemistry GA 211JP UT WOS:000081157700525 ER PT J AU Utschig, LM Schlesselman, SL Tiede, DM Thurnauer, MC AF Utschig, LM Schlesselman, SL Tiede, DM Thurnauer, MC TI A Zn(II) site in photosynthetic bacterial reaction centers that modulates electron transfer SO JOURNAL OF INORGANIC BIOCHEMISTRY LA English DT Meeting Abstract C1 Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. NR 1 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 0162-0134 J9 J INORG BIOCHEM JI J. Inorg. Biochem. PD APR 30 PY 1999 VL 74 IS 1-4 BP 323 EP 323 PG 1 WC Biochemistry & Molecular Biology; Chemistry, Inorganic & Nuclear SC Biochemistry & Molecular Biology; Chemistry GA 211JP UT WOS:000081157700602 ER PT J AU Wasinger, E Davis, MI Westre, TE Loeb, KE Zaleski, JM Hess, CD Orville, AM Hecht, SM Lipscomb, JD Hedman, B Solomon, EI Hodgson, KO AF Wasinger, E Davis, MI Westre, TE Loeb, KE Zaleski, JM Hess, CD Orville, AM Hecht, SM Lipscomb, JD Hedman, B Solomon, EI Hodgson, KO TI X-ray absorption spectroscopic investigations of mononuclear non-heme iron ferrous active sites SO JOURNAL OF INORGANIC BIOCHEMISTRY LA English DT Meeting Abstract C1 Stanford Univ, Dept Chem, Stanford, CA 94305 USA. Univ Virginia, Dept Chem & Biol, Charlottesville, VA 22901 USA. Univ Minnesota, Ctr Met Biocatalysis, Minneapolis, MN 55455 USA. Stanford Univ, Stanford Linear Accelerator Ctr, Stanford Synchrotron Radiat Lab, Stanford, CA 94309 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0162-0134 J9 J INORG BIOCHEM JI J. Inorg. Biochem. PD APR 30 PY 1999 VL 74 IS 1-4 BP 334 EP 334 PG 1 WC Biochemistry & Molecular Biology; Chemistry, Inorganic & Nuclear SC Biochemistry & Molecular Biology; Chemistry GA 211JP UT WOS:000081157700621 ER PT J AU Arko, AJ AF Arko, AJ TI Photoemission spectroscopy - Gaps, pseudogaps, and occam's razor SO SCIENCE LA English DT Editorial Material ID ELECTRONIC-STRUCTURE; FERMI-SURFACE; OXIDE C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Arko, AJ (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 8 TC 3 Z9 3 U1 1 U2 1 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 APR 30 PY 1999 VL 284 IS 5415 BP 752 EP 753 DI 10.1126/science.284.5415.752 PG 2 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 192AW UT WOS:000080056200029 ER PT J AU Ozawa, M Loong, CK AF Ozawa, M Loong, CK TI In situ X-ray and neutron powder diffraction studies of redox behavior in CeO2-containing oxide catalysts SO CATALYSIS TODAY LA English DT Article DE in situ; X-ray diffraction; CeO2; ZrO2; oxygen storage capacity; neutron diffraction; redox behavior ID CEO2-ZRO2 SOLID-SOLUTIONS; OXYGEN STORAGE CAPACITY; CARBON-MONOXIDE; CERIUM DIOXIDE; AUTOMOTIVE CATALYSTS; SURFACE-AREA; REDUCTION; TEMPERATURE; TRANSIENT; ZIRCONIA AB In situ X-ray and neutron diffraction experiments at high temperatures were performed to monitor the lattice response due to conversions between the Ce4+ and Ce3+ in CeO2-based oxide catalysts, CeO2, Ce1-xLaxO2-x/2 and Ce1-xZrxO2 with and without impregnation of Pt metal. The significant difference in the Ce4+ and Ce3+ ionic radius permitted a quantitative measurements of the fraction of Ce3+ in the cubic phases of crystalline CeO2 and the oxide solid solutions during the redox cycle. The reduction kinetics, kt={1-(1-x)(1/3))}(2) (x=fraction of Ce3+, t-time, k=constant) for CeO2 and Ce1-xLaxO2-x/2 were characterized from an analysis of the X-ray data collected under a CO/N-2 atmosphere at 500-700 degrees C. Pt-impregnated Ce0.1Zr0.9O2 was examined by neutron diffraction measurements under both CO/Ar and O-2/Ar atmospheres up to similar to 700 degrees C. Under a CO/Ar atmosphere, Pt-impregnation accelerates the reduction of Ce4+ to Ce3+ first on the interface of the metal and oxide particles, generating oxygen vacancies and releasing CO2 molecules. Subsequently, oxygen vacancies migrate to the bulk of the oxide particles. The significance of the redox behavior of CeO2 in automotive three-way catalysts for purification of exhaust pollutants is discussed. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Nagoya Inst Technol, CRL, Tajimi 5070071, Japan. Argonne Natl Lab, Div Intense Pulsed Neutron Source, Argonne, IL 60439 USA. RP Ozawa, M (reprint author), Nagoya Inst Technol, CRL, Tajimi 5070071, Japan. NR 75 TC 53 Z9 53 U1 2 U2 18 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-5861 J9 CATAL TODAY JI Catal. Today PD APR 29 PY 1999 VL 50 IS 2 BP 329 EP 342 DI 10.1016/S0920-5861(98)00513-6 PG 14 WC Chemistry, Applied; Chemistry, Physical; Engineering, Chemical SC Chemistry; Engineering GA 188NU UT WOS:000079855000012 ER PT J AU Tang, KQ Smith, RD AF Tang, KQ Smith, RD TI Theoretical prediction of charged droplet evaporation and fission in electrospray ionization SO INTERNATIONAL JOURNAL OF MASS SPECTROMETRY LA English DT Article DE electrospray ionization; theory; droplet fission; Rayleigh limit; droplets ID MASS-SPECTROMETRY AB A theoretical analysis was performed on the droplet asymmetric fission in electrospray ionization process. The formulated model is able to predict the diameter, charge and the percentage of charge at the Rayleigh charge limit for both progeny droplets and residue parent droplet during each fission process based upon possible different numbers of progeny droplets generated by the fission event. The evaporation time required for both the progeny droplets and the residue parent droplet to become unstable after each fission process was also calculated and compared. The results of these calculations showed that the evaporation time for the progeny droplets is more than an order of magnitude less than that of the residue parent droplet, indicating that the progeny droplets are the primary ion source for conventional electrospray ionization sources. (Int J Mass Spectrom 185/186/187 (1999) 97-105) (C) 1999 Elsevier Science B.V. C1 Pacific NW Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Smith, RD (reprint author), Pacific NW Lab, Environm Mol Sci Lab, Mail Stop K8-98,POB 999, Richland, WA 99352 USA. EM rd_smith@pnl.gov RI Smith, Richard/J-3664-2012 OI Smith, Richard/0000-0002-2381-2349 NR 21 TC 16 Z9 17 U1 0 U2 9 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 APR 29 PY 1999 VL 185 SI SI BP 97 EP 105 DI 10.1016/S1387-3806(98)14107-6 PG 9 WC Physics, Atomic, Molecular & Chemical; Spectroscopy SC Physics; Spectroscopy GA 188PV UT WOS:000079857900011 ER PT J AU Asano, KG Goeringer, DE McLuckey, SA AF Asano, KG Goeringer, DE McLuckey, SA TI Thermal dissociation in the quadrupole ion trap: ions derived from leucine enkephalin SO INTERNATIONAL JOURNAL OF MASS SPECTROMETRY LA English DT Article DE thermal dissociation; quadrupole ion trap; leucine enkephalin; ion temperatures ID TANDEM MASS-SPECTROMETRY; INFRARED RADIATIVE DISSOCIATION; COLLISION-INDUCED DISSOCIATION; SMALL CLUSTER IONS; GAS-PHASE; UNIMOLECULAR DISSOCIATION; PEPTIDE IONS; BLACKBODY RADIATION; REACTION-KINETICS; BUFFER GAS AB Rates of dissociation of protonated leucine enkephalin and the b(4)(+) fragment ion derived from protonated leucine enkephalin have been measured as a function of helium bath gas temperature in a quadrupole ion trap. Dissociation rates were observed to be insensitive to the amplitude of the trapping voltage over the range of values studied. This observation, along with theoretical arguments based on predicted levels of "rf heating," indicates that any internal excitation of the ions due to ion trap storage is minimal. The bath gas temperature can therefore be used to characterize the internal temperatures of the ions. This approximation is expected to be most valid for high mass ions and low mass bath gases, such as helium. Activation parameters were obtained from Arrhenius plots of the rate data, and master equation modeling of the activation, deactivation, and dissociation processes was performed to provide an indication as to how closely these ions approached high-pressure limit behavior. Protonated leucine enkephalin more closely approached the high-pressure limit than the b(4)(+) ion due to its larger size and the fact that the activation parameters were derived from somewhat lower dissociation rates. These studies suggest that the quadrupole ion trap operated in the presence of a light, heated bath gas can be used to obtain Arrhenius activation parameters from the dissociation kinetics of relatively high mass ions. (Int J Mass Spectrom 185/186/187 (1999) 207-219) (C) 1999 Elsevier Science B.V. C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP McLuckey, SA (reprint author), Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. EM mcluckeysa@ornl.gov RI McLuckey, Scott/B-2203-2009; Asano, Keiji/L-3164-2016 OI McLuckey, Scott/0000-0002-1648-5570; Asano, Keiji/0000-0003-2254-3586 NR 60 TC 42 Z9 42 U1 0 U2 20 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 APR 29 PY 1999 VL 185 SI SI BP 207 EP 219 DI 10.1016/S1387-3806(98)14116-7 PG 13 WC Physics, Atomic, Molecular & Chemical; Spectroscopy SC Physics; Spectroscopy GA 188PV UT WOS:000079857900022 ER PT J AU Cheung, YS Ng, CY AF Cheung, YS Ng, CY TI Vacuum ultraviolet single-photon and ultraviolet nonresonant two-photon pulsed field ionization photoelectron study of CH3SCH3 SO INTERNATIONAL JOURNAL OF MASS SPECTROMETRY LA English DT Article DE photoionization; photoelectron; ionization energy ID NEAR-THRESHOLD PHOTOIONIZATION; RESOLVED PHOTOIONIZATION; SYNCHROTRON-RADIATION; H2O; RESOLUTION; SPECTRUM; ENERGY; MOLECULES; STATE; PHOTODISSOCIATION AB The vacuum ultraviolet (VUV) single-photon and ultraviolet nonresonant two-photon (N2P) pulsed field ionization photoelectron (PFI-PE) spectra for CH,SCH, have been obtained in the energy range of 69 500-72 500 cm(-1). Vibrational structures observed in the VUV-PFI-PE and N2P-PFI-PE spectra are similar. Guided by the ab initio theoretical harmonic frequencies, we have assigned the vibrational bands resolved in these spectra. Using a semiempirical simulation scheme, together with ab initio theoretical rotational constants for CH3SCH3 and CH3SCH3+, we have also obtained a good fit to the contours of rotational branches resolved in the origin band of the VUV-PFI-PE spectrum. Taking into account the uncertainty of the simulation model used, we obtain a value of 70 097.3 +/- 2.0 cm(-1) (8.69096 +/- 0.00016 eV) for the adiabatic ionization energy of CH3SCH3. (C) 1999 Elsevier Science B.V. C1 Iowa State Univ, US DOE, Ames Lab, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Dept Chem, Ames, IA 50011 USA. RP Ng, CY (reprint author), Iowa State Univ, US DOE, Ames Lab, Ames, IA 50011 USA. EM cyng@ameslab.gov NR 37 TC 11 Z9 12 U1 0 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 APR 29 PY 1999 VL 185 SI SI BP 533 EP 543 DI 10.1016/S1387-3806(98)14124-6 PG 11 WC Physics, Atomic, Molecular & Chemical; Spectroscopy SC Physics; Spectroscopy GA 188PV UT WOS:000079857900050 ER PT J AU Basilevsky, MV Rostov, IV Newton, MD AF Basilevsky, MV Rostov, IV Newton, MD TI A two-dimensional Born-Oppenheimer treatment of intramolecular electron transfer reactions (vol 450, pg 69, 1998) SO JOURNAL OF ELECTROANALYTICAL CHEMISTRY LA English DT Correction C1 LY Karpov Phys Chem Res Inst, Moscow 103064, Russia. Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. RP Basilevsky, MV (reprint author), LY Karpov Phys Chem Res Inst, Ul Vorontsova Pole 10, Moscow 103064, Russia. NR 1 TC 0 Z9 0 U1 0 U2 1 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0022-0728 J9 J ELECTROANAL CHEM JI J. Electroanal. Chem. PD APR 29 PY 1999 VL 465 IS 2 BP 240 EP 240 DI 10.1016/S0022-0728(99)00112-6 PG 1 WC Chemistry, Analytical; Electrochemistry SC Chemistry; Electrochemistry GA 197KD UT WOS:000080363200016 ER PT J AU Lau, KC Li, WK Ng, CY Chiu, SW AF Lau, KC Li, WK Ng, CY Chiu, SW TI A Gaussian-2 study of isomeric C2H2N and C2H2N+ SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID G2 AB-INITIO; CARBANION SPECTROSCOPY; THERMOCHEMISTRY; ENERGETICS; ENERGIES; RADICALS; ANIONS; CH3O2; PHOTOIONIZATION; CATIONS AB The structures and energetics of the C2H2N and C2H2N+ isomers have been investigated using a modified Gaussian-2 (G2) method, which takes into account the energy correction due to spin contamination. At the QCISD(Full)/6-31G(d) level, C2H2N may exist as 12 stable isomers. In the order of decreasing stabilities, they are CH2CN (1), CH2NC (2), CHCNH (3), c-CH2CN (4), c-NCHCH (5), CHNCH (6), NH2CC (7), NHCHC (9), c-NHCHC (10), cis-CHCHN (12), cis-CHNHC (13), and trans-CHNHC (14). On the other hand, there are seven C2H2N+ isomers. In the order of decreasing stabilities, they are c-NCHCH+ (5(+)), CH2CN+ (1(+)), CH2NC+ (2(+)), CHCNH+ (3(+)), CHNCH+ (6(+)), c-NHCHC+ (10(+)), and NH2CC+ (7(+)). The G2, result for the ionization energy of 1 and the Delta H degrees(f298) values of 1 and 1(+) are in good agreement with the available experimental data. However, the G2 results for radicals 2 and 5 as well as cations 2(+) and 5(+) do not agree with the experimental data in the literature. This calls for a reexamination of the experimental results. Furthermore, in a recent study of the reaction between nitrogen atom and vinyl radical, a C2H2N radical was formed with an ionization energy < 9.64 eV. On the basis of our calculations and known reactivity of the reactants, it is concluded that the unidentified isomer is likely to be 2. C1 Chinese Univ Hong Kong, Dept Chem, Shatin, NT, Peoples R China. Iowa State Univ, US DOE, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Chem, Ames, IA 50011 USA. Univ Illinois, Natl Ctr Supercomp Applicat, Urbana, IL 61801 USA. RP Chinese Univ Hong Kong, Dept Chem, Shatin, NT, Peoples R China. OI LAU, Kai Chung /0000-0003-2125-6841 NR 31 TC 20 Z9 20 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5639 J9 J PHYS CHEM A JI J. Phys. Chem. A PD APR 29 PY 1999 VL 103 IS 17 BP 3330 EP 3335 DI 10.1021/jp984540i PG 6 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 192DR UT WOS:000080063400023 ER PT J AU Miranda, PB Shen, YR AF Miranda, PB Shen, YR TI Liquid interfaces: A study by sum-frequency vibrational spectroscopy SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Review ID OPTICAL 2ND-HARMONIC GENERATION; AIR-WATER-INTERFACE; ENHANCED RAMAN-SCATTERING; SODIUM DODECYL-SULFATE; NORMAL-ALKYL CHAINS; H STRETCHING MODES; IN-SITU; HYDROPHOBIC SURFACE; ELECTROCHEMICAL INTERFACE; SOLID-SURFACES AB Liquid interfaces play a fundamental role in science and technology. The development of surface-sensitive probes capable of yielding molecular information about these interfaces is of great importance. This paper gives an overview of our and some others' recent work on vibrational spectroscopy of liquid interfaces by the sum-frequency generation (SFG) technique. This technique, being highly surface specific and applicable to all interfaces accessible by light, has been proven to be a most powerful analytical tool for liquid interfaces. A wide range of systems have been studied including neat liquid surfaces, solid/liquid and liquid/liquid interfaces, surfactants at liquid interfaces, and electrochemical interfaces. In many cases, SFG is shown to be the only technique available that can provide detailed information about a liquid interface at the molecular level. C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Shen, YR (reprint author), Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. RI Miranda, Paulo/C-5933-2012 OI Miranda, Paulo/0000-0002-2890-0268 NR 191 TC 456 Z9 459 U1 13 U2 175 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 APR 29 PY 1999 VL 103 IS 17 BP 3292 EP 3307 DI 10.1021/jp9843757 PG 16 WC Chemistry, Physical SC Chemistry GA 192DU UT WOS:000080063700002 ER PT J AU Park, NG Schlichthorl, G van de Lagemaat, J Cheong, HM Mascarenhas, A Frank, AJ AF Park, NG Schlichthorl, G van de Lagemaat, J Cheong, HM Mascarenhas, A Frank, AJ TI Dye-sensitized TiO2 solar cells: Structural and photoelectrochemical characterization of nanocrystalline electrodes formed from the hydrolysis of TiCl4 SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID MODULATED PHOTOCURRENT SPECTROSCOPY; RAMAN-SPECTRA; ENERGY-CONVERSION; TITANIUM-DIOXIDE; RUTILE; LIGHT; TRANSPORT; FILMS; PHOTOSENSITIZATION; COMPLEXES AB The structure and photoelectrochemical properties of TiO2 films deposited onto SnO2 conducting glass from the ambient hydrolysis of TiCl4 and annealed at temperatures ranging from 100 to 500 degrees C were studied by Raman spectroscopy, X-ray diffraction (XRD), transmission electron microscopy (TEM), intensity-modulated photovoltage spectroscopy (IMVS), and intensity-modulated photocurrent spectroscopy (IMPS) measurements. Analysis of the XRD and Raman spectra shows that TiCl4-produced TiO2 films have the rutile structure, regardless of annealing temperature. The TEM reveals that the rutile TiO2 films consist of rod-shaped particles that grow with increasing annealing temperature. The AM-1.5 short-circuit photocurrent J(sc) and open-circuit photovoltage V-oc of Ru[LL'(NCS)2]-sensitized (L = 2,2'-bypyridyl-4,4'-dicarboxylic acid, L' = 2,2'-bipyridyl-4,4-ditetrabutylammoniumcarboxylate) 4.5 mu m thick rutile films increase significantly with annealing temperature, from 1.1 mA/cm(2) and 602 mV at 100 degrees C to 8.7 mA/cm(2) and 670 mV at 500 degrees C, Studies of the incident photon-to-current conversion efficiency (IPCE), the photocurrent-voltage characteristics, the optical appearance, the water content, and the particle size of the films indicate that the increase of both J(sc) and V-oc with annealing temperature is due, in part, to increased dye adsorption resulting fr om the evaporation of surface water and the improved light-scattering properties of the film associated with the growth of rutile particles. IMVS and IMPS measurements indicate that variations of the charge-collection efficiency of the cell, which increases from 86% for the 300 degrees C annealed samples to above 99% for the 500 degrees C annealed samples, have only a minor effect on J(sc). Analysis of the time constants at open circuit and short circuit for a given electron injection current suggests that the ratio of free-to-trapped electrons at short circuit decreases and the diffusion coefficient of free electrons increases with annealing temperature. Raman and XRD measurements and other observations indicate that treating transparent nanocrystalline anatase TiO2 electrodes with TiCl4 produces a translucent overlayer of rutile TiO2. The increased film thickness and light-scattering characteristics of the rutile overlayer may explain, in part, the improved IPCE observed for dye-sensitized TiCl4-treated nanocrystalline anatase TiO2 electrodes. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Frank, AJ (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. RI Cheong, Hyeonsik/D-7424-2012; van de Lagemaat, Jao/J-9431-2012; Park, Nam-Gyu/F-2477-2014 OI Cheong, Hyeonsik/0000-0002-2347-4044; NR 43 TC 309 Z9 312 U1 8 U2 124 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 APR 29 PY 1999 VL 103 IS 17 BP 3308 EP 3314 DI 10.1021/jp984529i PG 7 WC Chemistry, Physical SC Chemistry GA 192DU UT WOS:000080063700003 ER PT J AU Buranda, T Jones, GM Nolan, JP Keij, J Lopez, GP Sklar, LA AF Buranda, T Jones, GM Nolan, JP Keij, J Lopez, GP Sklar, LA TI Ligand receptor dynamics at streptavidin-coated particle surfaces: A flow cytometric and spectrofluorimetric study SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID EGG-WHITE AVIDIN; CONFORMATIONAL-CHANGES; FLUORESCENCE LIFETIME; BIOTIN; BINDING; PEPTIDE; COMPLEX; DISSOCIATION; ENHANCEMENT; DERIVATIVES AB We have the studied the binding of 5-((N-(5-(N-(6-(biotinoyl)amino)hexanoyl fluorescein (fluorescein biotin) to 6.2 mu m diameter, streptavidin-coated polystyrene beads using a combination of fluorimetric and flow cytometric methods. We have determined the average number of binding sites per bead, the extent of fluorescein quenching upon binding to the bead, and the association and dissociation kinetics. We estimate the site number to be approximate to 1 million per bead. The binding of the fluorescein biotin ligand occurs in steps where the insertion of the biotin moiety into one receptor pocket is followed immediately by the capture of the fluorescein moiety by a neighboring binding pocket; fluorescence quenching is a consequence of this secondary binding. At high surface coverage, the dominant mechanism of quenching appears to be via the formation of nonfluorescent nearest-neighbor aggregates. At early times, the binding process is characterized by biphasic association and dissociation kinetics which are remarkably dependent on the initial concentration of the ligand. The rate constant for binding to the first receptor pocket of a streptavidin molecule is approximate to(1.3 +/- 0.3) x 10(7) M-1 s(-1). The rate of binding of a second biotin may be reduced due to steric interference. The early time dissociative behavior is in sharp contrast to the typical stability associated with this system. The dissociation rate constant is as high as 0.05 s(-1) shortly after binding, but decreases by 3 orders of magnitude after 3 h of binding. Potential sources for the time dependence of the dissociation rate constant are discussed. C1 Univ New Mexico, Sch Med, Ctr Canc, Albuquerque, NM 87131 USA. Univ New Mexico, Sch Med, Dept Pathol, Albuquerque, NM 87131 USA. Univ New Mexico, Dept Chem, Albuquerque, NM 87131 USA. Univ Calif Los Alamos Natl Lab, Life Sci Div & Natl Flow Cytometry Resources, Los Alamos, NM 87545 USA. RP Buranda, T (reprint author), Univ New Mexico, Sch Med, Ctr Canc, Albuquerque, NM 87131 USA. NR 46 TC 60 Z9 61 U1 0 U2 7 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5647 J9 J PHYS CHEM B JI J. Phys. Chem. B PD APR 29 PY 1999 VL 103 IS 17 BP 3399 EP 3410 DI 10.1021/jp983842h PG 12 WC Chemistry, Physical SC Chemistry GA 192DU UT WOS:000080063700016 ER PT J AU Smith, RS Kay, BD AF Smith, RS Kay, BD TI The existence of supercooled liquid water at 150 K SO NATURE LA English DT Article ID AMORPHOUS SOLID WATER; SELF-DIFFUSION; GLASS-TRANSITION; PHASE-BEHAVIOR; T-G; ICE; CRYSTALLIZATION; DESORPTION; STABILITY; MODEL AB Supercooled water may offer clues to the anomalous properties of its normal liquid state(1). The supercooled state also shows anomalous thermodynamic and transport properties at low temperatures(2-4). Although there are several theoretical explanations for this behaviour, no consensus has emerged(1,2,5-12). Some theories preclude the existence of the supercooled liquid below an apparent thermodynamic singularity at 228 K (refs 2, 7, 9); others are consistent with a continuous region of metastability from the melting point at 273 K to the glass transition temperature at 136 K (refs 6, 8, 13), But the data needed to distinguish between these possibilities have not yet been forthcoming. Here we determine the diffusivity of amorphous ice by studying isotope intermixing in films less than 500 nanometres thick. The magnitude and temperature dependence of the diffusivity is consistent with the idea that the amorphous solid water melts into a deeply metastable extension of normal liquid water before crystallizing at 160 K. This argues against the idea of a singularity in the supercooled regime at ambient pressure. C1 Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Kay, BD (reprint author), Pacific NW Natl Lab, Environm Mol Sci Lab, POB 999,Mail Stop K8-88, Richland, WA 99352 USA. RI Smith, Scott/G-2310-2015 OI Smith, Scott/0000-0002-7145-1963 NR 36 TC 279 Z9 281 U1 4 U2 50 PU MACMILLAN MAGAZINES LTD PI LONDON PA PORTERS SOUTH, 4 CRINAN ST, LONDON N1 9XW, ENGLAND SN 0028-0836 J9 NATURE JI Nature PD APR 29 PY 1999 VL 398 IS 6730 BP 788 EP 791 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 192BL UT WOS:000080058100052 ER PT J AU Acciarri, M Achard, P Adriani, O Aguilar-Benitez, M Alcaraz, J Alemanni, G Allaby, J Aloisio, A Alviggi, MG Ambrosi, G Anderhub, H Andreev, VP Angelescu, T Anselmo, F Arefiev, A Azemoon, T Aziz, T Bagnaia, P Baksay, L Balandras, A Ball, RC Banerjee, S Banerjee, S Banicz, K Barczyk, A Barillere, R Barone, L Bartalini, P Basile, M Battiston, R Bay, A Becattini, F Becker, U Behner, F Berdugo, J Berges, P Bertucci, B Betev, BL Bhattacharya, S Biasini, M Biland, A Blaising, JJ Blyth, SC Bobbink, GJ Bock, R Bohm, A Boldizsar, L Borgia, B Bourilkov, D Bourquin, M Braccini, S Branson, JG Brigljevic, V Brochu, F Buffini, A Buijs, A Burger, JD Burger, WJ Busenitz, J Button, A Cai, XD Campanelli, M Capell, M Romeo, GC Carlino, G Cartacci, AM Casaus, J Castellini, G Cavallari, F Cavallo, N Cecchi, C Cerrada, M Cesaroni, F Chamizo, M Chang, YH Chaturvedi, UK Chemarin, M Chen, A Chen, G Chen, GM Chen, HF Chen, HS Chereau, X Chiefari, G Cifarelli, L Cindolo, F Civinini, C Clare, I Clare, R Coignet, G Colijn, AP Colino, N Costantini, S Cotorobai, F de la Cruz, B Csilling, A Dai, TS van Dalen, JA D'Alessandro, R de Asmundis, R Deglon, P Degre, A Deiters, K della Volpe, D Denes, P DeNotaristefani, F De Salvo, A Diemoz, M van Dierendonck, D Di Lodovico, F Dionisi, C Dittmar, M Dominguez, A Doria, A Dova, MT Duchesneau, D Dufournand, D Duinker, P Duran, I El Mamouni, H Engler, A Eppling, FJ Erne, FC Extermann, P Fabre, M Faccini, R Falagan, MA Falciano, S Favara, A Fay, J Fedin, O Felcini, M Ferguson, T Ferroni, F Fesefeldt, H Fiandrini, E Field, JH Filthaut, F Fisher, PH Fisk, I Forconi, G Fredj, L Freudenreich, K Furetta, C Galaktionov, Y Ganguli, SN Garcia-Abia, P Gataullin, M Gau, SS Gentile, S Gheordanescu, N Giagu, S Goldfarb, S Gong, ZF Gruenewald, MW van Gulik, R Gupta, VK Gurtu, A Gutay, LJ Haas, D Hartmann, B Hasan, A Hatzifotiadou, D Hebbeker, T Herve, A Hidas, P Hirschfelder, J Hofer, H Holzner, G Hoorani, H Hou, SR Iashvili, I Jin, BN Jones, LW de Jong, P Josa-Mutuberria, I Khan, RA Kamrad, D Kapustinsky, JS Kaur, M Kienzle-Focacci, MN Kim, D Kim, DH Kim, JK Kim, SC Kinnison, WW Kirkby, J Kiss, D Kittel, W Klimentov, A Konig, AC Kopp, A Korolko, I Koutsenko, V Kraemer, RW Krenz, W Kunin, A Lacentre, P de Guevara, PL Laktineh, I Landi, G Lapoint, C Lassila-Perini, K Laurikainen, P Lavorato, A Lebeau, M Lebedev, A Lebrun, P Lecomte, P Lecoq, P Le Coultre, P Lee, HJ Le Goff, JM Leiste, R Leonardi, E Levtchenko, P Li, C Lin, CH Lin, WT Linde, FL Lista, L Liu, ZA Lohmann, W Longo, E Lu, YS Lubelsmeyer, K Luci, C Luckey, D Luminari, L Lustermann, W Ma, WG Maity, M Majumder, G Malgeri, L Malinin, A Mana, C Mangeol, D Marchesini, P Marian, G Martin, JP Marzano, F Massaro, GGG Mazumdar, K McNeil, RR Mele, S Merola, L Meschini, M Metzger, WJ von der Mey, M Migani, D Mihul, A Milcent, H Mirabelli, G Mnich, J Molnar, P Monteleoni, B Moulik, T Muanza, GS Muheim, F Muijs, AJM Nahn, S Napolitano, M Nessi-Tedaldi, F Newman, H Niessen, T Nippe, A Nisati, A Nowak, H Oh, YD Organtini, G Ostonen, R Palomares, C Pandoulas, D Paoletti, S Paolucci, P Park, HK Park, IH Pascale, G Passaleva, G Patricelli, S Paul, T Pauluzzi, M Paus, C Pauss, F Peach, D Pedace, M Pei, YJ Pensotti, S Perret-Gallix, D Petersen, B Petrak, S Piccolo, D Pieri, M Piroue, PA Pistolesi, E Plyaskin, V Pohl, M Pojidaev, V Postema, H Pothier, J Produit, N Prokofiev, D Quartieri, J Rahal-Callot, G Raja, N Rancoita, PG Raven, G Razis, P Ren, D Rescigno, M Reucroft, S van Rhee, T Riemann, S Riles, K Robohm, A Rodin, J Roe, BP Romero, L Rosier-Lees, S Roth, S Rubio, JA Ruschmeier, D Rykaczewski, H Sakar, S Salicio, J Sanchez, E Sanders, MP Sarakinos, ME Schafer, C Schegelsky, V Schmidt-Kaerst, S Schmitz, D Scholz, N Schopper, H Schotanus, DJ Schwenke, J Schwering, G Sciacca, C Sciarrino, D Servoli, L Shevchenko, S Shivarov, N Shoutko, V Shukla, J Shumilov, E Shvorob, A Siedenburg, T Son, D Smith, B Spillantini, P Steuer, M Stickland, DP Stone, A Stone, H Stoyanov, B Straessner, A Sudhakar, K Sultanov, G Sun, LZ Suter, H Swain, JD Szillasi, Z Tang, XW Tauscher, L Taylor, L Timmermans, C Ting, SCC Ting, SM Tonwar, SC Toth, J Tully, C Tung, KL Uchida, Y Ulbricht, J Valente, E Vesztergombi, G Vetlitsky, I Viertel, G Villa, S Vivargent, M Vlachos, S Vogel, H Vogt, H Vorobiev, I Vorobyov, AA Vorvolakos, A Wadhwa, M Wallraff, W Wang, JC Wang, XL Wang, ZM Weber, A Wilkens, H Wu, SX Wynhoff, S Xia, L Xu, ZZ Yang, BZ Yang, CG Yang, HJ Yang, M Ye, JB Yeh, SC You, JM Zalite, A Zalite, Y Zemp, P Zeng, Y Zhang, ZP Zhu, GY Zhu, RY Zichichi, A Ziegler, F Zilizi, G AF Acciarri, M Achard, P Adriani, O Aguilar-Benitez, M Alcaraz, J Alemanni, G Allaby, J Aloisio, A Alviggi, MG Ambrosi, G Anderhub, H Andreev, VP Angelescu, T Anselmo, F Arefiev, A Azemoon, T Aziz, T Bagnaia, P Baksay, L Balandras, A Ball, RC Banerjee, S Banerjee, S Banicz, K Barczyk, A Barillere, R Barone, L Bartalini, P Basile, M Battiston, R Bay, A Becattini, F Becker, U Behner, F Berdugo, J Berges, P Bertucci, B Betev, BL Bhattacharya, S Biasini, M Biland, A Blaising, JJ Blyth, SC Bobbink, GJ Bock, R Bohm, A Boldizsar, L Borgia, B Bourilkov, D Bourquin, M Braccini, S Branson, JG Brigljevic, V Brochu, F Buffini, A Buijs, A Burger, JD Burger, WJ Busenitz, J Button, A Cai, XD Campanelli, M Capell, M Romeo, GC Carlino, G Cartacci, AM Casaus, J Castellini, G Cavallari, F Cavallo, N Cecchi, C Cerrada, M Cesaroni, F Chamizo, M Chang, YH Chaturvedi, UK Chemarin, M Chen, A Chen, G Chen, GM Chen, HF Chen, HS Chereau, X Chiefari, G Cifarelli, L Cindolo, F Civinini, C Clare, I Clare, R Coignet, G Colijn, AP Colino, N Costantini, S Cotorobai, F de la Cruz, B Csilling, A Dai, TS van Dalen, JA D'Alessandro, R de Asmundis, R Deglon, P Degre, A Deiters, K della Volpe, D Denes, P DeNotaristefani, F De Salvo, A Diemoz, M van Dierendonck, D Di Lodovico, F Dionisi, C Dittmar, M Dominguez, A Doria, A Dova, MT Duchesneau, D Dufournand, D Duinker, P Duran, I El Mamouni, H Engler, A Eppling, FJ Erne, FC Extermann, P Fabre, M Faccini, R Falagan, MA Falciano, S Favara, A Fay, J Fedin, O Felcini, M Ferguson, T Ferroni, F Fesefeldt, H Fiandrini, E Field, JH Filthaut, F Fisher, PH Fisk, I Forconi, G Fredj, L Freudenreich, K Furetta, C Galaktionov, Y Ganguli, SN Garcia-Abia, P Gataullin, M Gau, SS Gentile, S Gheordanescu, N Giagu, S Goldfarb, S Gong, ZF Gruenewald, MW van Gulik, R Gupta, VK Gurtu, A Gutay, LJ Haas, D Hartmann, B Hasan, A Hatzifotiadou, D Hebbeker, T Herve, A Hidas, P Hirschfelder, J Hofer, H Holzner, G Hoorani, H Hou, SR Iashvili, I Jin, BN Jones, LW de Jong, P Josa-Mutuberria, I Khan, RA Kamrad, D Kapustinsky, JS Kaur, M Kienzle-Focacci, MN Kim, D Kim, DH Kim, JK Kim, SC Kinnison, WW Kirkby, J Kiss, D Kittel, W Klimentov, A Konig, AC Kopp, A Korolko, I Koutsenko, V Kraemer, RW Krenz, W Kunin, A Lacentre, P de Guevara, PL Laktineh, I Landi, G Lapoint, C Lassila-Perini, K Laurikainen, P Lavorato, A Lebeau, M Lebedev, A Lebrun, P Lecomte, P Lecoq, P Le Coultre, P Lee, HJ Le Goff, JM Leiste, R Leonardi, E Levtchenko, P Li, C Lin, CH Lin, WT Linde, FL Lista, L Liu, ZA Lohmann, W Longo, E Lu, YS Lubelsmeyer, K Luci, C Luckey, D Luminari, L Lustermann, W Ma, WG Maity, M Majumder, G Malgeri, L Malinin, A Mana, C Mangeol, D Marchesini, P Marian, G Martin, JP Marzano, F Massaro, GGG Mazumdar, K McNeil, RR Mele, S Merola, L Meschini, M Metzger, WJ von der Mey, M Migani, D Mihul, A Milcent, H Mirabelli, G Mnich, J Molnar, P Monteleoni, B Moulik, T Muanza, GS Muheim, F Muijs, AJM Nahn, S Napolitano, M Nessi-Tedaldi, F Newman, H Niessen, T Nippe, A Nisati, A Nowak, H Oh, YD Organtini, G Ostonen, R Palomares, C Pandoulas, D Paoletti, S Paolucci, P Park, HK Park, IH Pascale, G Passaleva, G Patricelli, S Paul, T Pauluzzi, M Paus, C Pauss, F Peach, D Pedace, M Pei, YJ Pensotti, S Perret-Gallix, D Petersen, B Petrak, S Piccolo, D Pieri, M Piroue, PA Pistolesi, E Plyaskin, V Pohl, M Pojidaev, V Postema, H Pothier, J Produit, N Prokofiev, D Quartieri, J Rahal-Callot, G Raja, N Rancoita, PG Raven, G Razis, P Ren, D Rescigno, M Reucroft, S van Rhee, T Riemann, S Riles, K Robohm, A Rodin, J Roe, BP Romero, L Rosier-Lees, S Roth, S Rubio, JA Ruschmeier, D Rykaczewski, H Sakar, S Salicio, J Sanchez, E Sanders, MP Sarakinos, ME Schafer, C Schegelsky, V Schmidt-Kaerst, S Schmitz, D Scholz, N Schopper, H Schotanus, DJ Schwenke, J Schwering, G Sciacca, C Sciarrino, D Servoli, L Shevchenko, S Shivarov, N Shoutko, V Shukla, J Shumilov, E Shvorob, A Siedenburg, T Son, D Smith, B Spillantini, P Steuer, M Stickland, DP Stone, A Stone, H Stoyanov, B Straessner, A Sudhakar, K Sultanov, G Sun, LZ Suter, H Swain, JD Szillasi, Z Tang, XW Tauscher, L Taylor, L Timmermans, C Ting, SCC Ting, SM Tonwar, SC Toth, J Tully, C Tung, KL Uchida, Y Ulbricht, J Valente, E Vesztergombi, G Vetlitsky, I Viertel, G Villa, S Vivargent, M Vlachos, S Vogel, H Vogt, H Vorobiev, I Vorobyov, AA Vorvolakos, A Wadhwa, M Wallraff, W Wang, JC Wang, XL Wang, ZM Weber, A Wilkens, H Wu, SX Wynhoff, S Xia, L Xu, ZZ Yang, BZ Yang, CG Yang, HJ Yang, M Ye, JB Yeh, SC You, JM Zalite, A Zalite, Y Zemp, P Zeng, Y Zhang, ZP Zhu, GY Zhu, RY Zichichi, A Ziegler, F Zilizi, G CA L3 Collaboration TI chi(c2) formation in two-photon collisions at LEP SO PHYSICS LETTERS B LA English DT Article ID CHARMONIUM STATES; L3 EXPERIMENT; DECAYS; DETECTOR; MESONS; QCD AB Two-photon formation of the charmonium resonance chi(c2), has been studied with the L3 detector at LEP. The chi(c2) is identified through its decay chi(c2) --> gamma J/psi, with a subsequent decay J/psi --> e(+)e(-) or J/psi --> mu(+)mu(-). With an integrated luminosity of 140 pb(-1) at root s similar or equal to 91 GeV and 52 pb(-1) at root s similar or equal to 183 GeV, we measure the two-photon width of the chi(c2) to be Gamma(gamma gamma)(chi(c2)) = 1.02 +/- 0.40 (stat.) +/- 0.15 (sys.) +/- 0.09(BR.) keV. (C) 1999 Published by Elsevier Science B.V. All rights reserved. C1 Ist Nazl Fis Nucl, Sez Milano, I-20133 Milan, Italy. Rhein Westfal TH Aachen, Inst Phys 3, D-52056 Aachen, Germany. Rhein Westfal TH Aachen, Inst Phys 1, D-52056 Aachen, Germany. NIKHEF H, Natl Lab High Energy Phys, NL-1009 DB Amsterdam, Netherlands. Univ Amsterdam, NL-1009 DB Amsterdam, Netherlands. Univ Michigan, Ann Arbor, MI 48109 USA. Lab Annecy Le Vieux Phys Particules, LAPP, IN2P3, CNRS, F-74941 Annecy Le Vieux, France. Univ Basel, Inst Phys, CH-4056 Basel, Switzerland. Louisiana State Univ, Baton Rouge, LA 70803 USA. Inst High Energy Phys, Beijing 100039, Peoples R China. Humboldt Univ, D-10099 Berlin, Germany. Univ Bologna, I-40126 Bologna, Italy. Ist Nazl Fis Nucl, Sez Bologna, I-40126 Bologna, Italy. Tata Inst Fundamental Res, Bombay 400005, Maharashtra, India. Northeastern Univ, Boston, MA 02115 USA. Inst Atom Phys, R-76900 Bucharest, Romania. Univ Bucharest, R-76900 Bucharest, Romania. Hungarian Acad Sci, Cent Res Inst Phys, H-1525 Budapest 114, Hungary. MIT, Cambridge, MA 02139 USA. Ist Nazl Fis Nucl, Sez Firenze, I-50125 Florence, Italy. Univ Florence, I-50125 Florence, Italy. CERN, European Lab Particle Phys, CH-1211 Geneva 23, Switzerland. FBLJA Project, World Lab, CH-1211 Geneva 23, Switzerland. Univ Geneva, CH-1211 Geneva 4, Switzerland. Univ Sci & Technol China, USTC, Hefei 230029, Anhui, Peoples R China. Res Inst High Energy Phys, SEFT, SF-00014 Helsinki, Finland. Univ Lausanne, CH-1015 Lausanne, Switzerland. Ist Nazl Fis Nucl, Sez Lecce, I-73100 Lecce, Italy. Univ Lecce, I-73100 Lecce, Italy. Los Alamos Natl Lab, Los Alamos, NM 87544 USA. Univ Lyon 1, CNRS, IN2P3, Inst Phys Nucl, F-69622 Villeurbanne, France. CIEMAT, E-28040 Madrid, Spain. Ist Nazl Fis Nucl, Sez Milano, I-20133 Milan, Italy. Inst Theoret & Expt Phys, Moscow 117259, Russia. Ist Nazl Fis Nucl, Sez Napoli, I-80125 Naples, Italy. Univ Naples Federico II, I-80125 Naples, Italy. Univ Cyprus, Dept Nat Sci, Nicosia, Cyprus. Catholic Univ Nijmegen, NL-6525 ED Nijmegen, Netherlands. Natl Inst Nucl Phys & High Energy Phys, NL-6525 ED Nijmegen, Netherlands. CALTECH, Pasadena, CA 91125 USA. Ist Nazl Fis Nucl, Sez Perugia, I-06100 Perugia, Italy. Univ Perugia, I-06100 Perugia, Italy. Carnegie Mellon Univ, Pittsburgh, PA 15213 USA. Princeton Univ, Princeton, NJ 08544 USA. Ist Nazl Fis Nucl, Sez Roma, I-00185 Rome, Italy. Univ Roma La Sapienza, I-00185 Rome, Italy. Inst Phys Nucl, St Petersburg, Russia. Univ Salerno, I-84100 Salerno, Italy. Ist Nazl Fis Nucl, I-84100 Salerno, Italy. Univ Calif San Diego, San Diego, CA 92093 USA. Univ Santiago, Dept Fis Particulas Elementales, E-15706 Santiago De Compostela, Spain. Bulgarian Acad Sci, Cent Lab Mechatron & Instrumentat, BU-1113 Sofia, Bulgaria. Korea Adv Inst Sci & Technol, Ctr High Energy Phys, Taejon 305701, South Korea. Univ Alabama, University, AL 35486 USA. Univ Utrecht, NL-3584 CB Utrecht, Netherlands. NIKHEF H, NL-3584 CB Utrecht, Netherlands. Purdue Univ, W Lafayette, IN 47907 USA. Paul Scherrer Inst, CH-5232 Villigen, Switzerland. DESY, Inst Hochenergiephys, D-15738 Zeuthen, Germany. Swiss Fed Inst Technol, CH-8093 Zurich, Switzerland. Univ Hamburg, D-22761 Hamburg, Germany. Natl Cent Univ, Chungli 32054, Taiwan. Natl Tsing Hua Univ, Dept Phys, Hsinchu, Taiwan. RP Acciarri, M (reprint author), Ist Nazl Fis Nucl, Sez Milano, Via Celoria 16, I-20133 Milan, Italy. RI Achard, Pablo/C-2983-2009; Sanchez, Eusebio/H-5228-2015; Duran, Ignacio/H-7254-2015; Rancoita, Pier Giorgio/J-9896-2015; Hoorani, Hafeez/D-1791-2013; Palomares, Carmen/H-7783-2015; Fedin, Oleg/H-6753-2016; Roth, Stefan/J-2757-2016; Di Lodovico, Francesca/L-9109-2016; Yang, Haijun/O-1055-2015; Fiandrini, Emanuele/C-4549-2008; Lista, Luca/C-5719-2008; Kirkby, Jasper/A-4973-2012; Servoli, Leonello/E-6766-2012; bertucci, bruna/J-5237-2012; Cavallo, Nicola/F-8913-2012; Cerrada, Marcos/J-6934-2014; de la Cruz, Begona/K-7552-2014; Josa, Isabel/K-5184-2014; Vogel, Helmut/N-8882-2014; Ferguson, Thomas/O-3444-2014; Berdugo, Javier/A-2858-2015; D'Alessandro, Raffaello/F-5897-2015 OI Filthaut, Frank/0000-0003-3338-2247; Achard, Pablo/0000-0002-4865-3196; Sanchez, Eusebio/0000-0002-9646-8198; Rancoita, Pier Giorgio/0000-0002-1990-4283; Palomares, Carmen/0000-0003-4374-9065; Roth, Stefan/0000-0003-3616-2223; Di Lodovico, Francesca/0000-0003-3952-2175; Sciacca, Crisostomo/0000-0002-8412-4072; Kirkby, Jasper/0000-0003-2341-9069; Servoli, Leonello/0000-0003-1725-9185; Cerrada, Marcos/0000-0003-0112-1691; Vogel, Helmut/0000-0002-6109-3023; Ferguson, Thomas/0000-0001-5822-3731; Berdugo, Javier/0000-0002-7911-8532; D'Alessandro, Raffaello/0000-0001-7997-0306 NR 31 TC 25 Z9 25 U1 1 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 EI 1873-2445 J9 PHYS LETT B JI Phys. Lett. B PD APR 29 PY 1999 VL 453 IS 1-2 BP 73 EP 82 DI 10.1016/S0370-2693(99)00279-8 PG 10 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 195JD UT WOS:000080246100010 ER PT J AU Acciarri, M Achard, P Adriani, O Aguilar-Benitez, M Alcaraz, J Alemanni, G Allaby, J Aloisio, A Alviggi, MG Ambrosi, G Anderhub, H Andreev, VP Angelescu, T Anselmo, F Arefiev, A Azemoon, T Aziz, T Bagnaia, P Baksay, L Balandras, A Ball, RC Banerjee, S Banerjee, S Banicz, K Barczyk, A Barillere, R Barone, L Bartalini, P Basile, M Battiston, R Bay, A Becattini, F Becker, U Behner, F Berdugo, J Berges, P Bertucci, B Betev, BL Bhattacharya, S Biasini, M Biland, A Blaising, JJ Blyth, SC Bobbink, GJ Bock, R Bohm, A Boldizsar, L Borgia, B Bourilkov, D Bourquin, M Braccini, S Branson, JG Brigljevic, V Brochu, F Buffini, A Buijs, A Burger, JD Burger, WJ Busenitz, J Button, A Cai, XD Campanelli, M Capell, M Romeo, GC Carlino, G Cartacci, AM Casaus, J Castellini, G Cavallari, F Cavallo, N Cecchi, C Cerrada, M Cesaroni, F Chamizo, M Chang, YH Chaturvedi, UK Chemarin, M Chen, A Chen, G Chen, GM Chen, HF Chen, HS Chereau, X Chiefari, G Cifarelli, L Cindolo, F Civinini, C Clare, I Clare, R Coignet, G Colijn, AP Colino, N Costantini, S Cotorobai, F de la Cruz, B Csilling, A Dai, TS van Dalen, JA D'Alessandro, R de Asmundis, R Deglon, P Degre, A Deiters, K della Volpe, D Denes, P DeNotaristefani, F De Salvo, A Diemoz, M van Dierendonck, D Di Lodovico, F Dionisi, C Dittmar, M Dominguez, A Doria, A Dova, MT Duchesneau, D Dufournand, D Duinker, P Duran, I El Mamouni, H Engler, A Eppling, FJ Erne, FC Extermann, P Fabre, M Faccini, R Falagan, MA Falciano, S Favara, A Fay, J Fedin, O Felcini, M Ferguson, T Ferroni, F Fesefeldt, H Fiandrini, E Field, JH Filthaut, F Fisher, PH Fisk, I Forconi, G Fredj, L Freudenreich, K Furetta, C Galaktionov, Y Ganguli, SN Garcia-Abia, P Gataullin, M Gau, SS Gentile, S Gheordanescu, N Giagu, S Goldfarb, S Gong, ZF Gruenewald, MW van Gulik, R Gupta, VK Gurtu, A Gutay, LJ Haas, D Hartmann, B Hasan, A Hatzifotiadou, D Hebbeker, T Herve, A Hidas, P Hirschfelder, J Hofer, H Holzner, G Hoorani, H Hou, SR Iashvili, I Jin, BN Jones, LW de Jong, P Josa-Mutuberria, I Khan, RA Kamrad, D Kapustinsky, JS Kaur, M Kienzle-Focacci, MN Kim, D Kim, DH Kim, JK Kim, SC Kinnison, WW Kirkby, J Kiss, D Kittel, W Klimentov, A Konig, AC Kopp, A Korolko, I Koutsenko, V Kraemer, RW Krenz, W Kunin, A Lacentre, P de Guevara, PL Laktineh, I Landi, G Lapoint, C Lassila-Perini, K Laurikainen, P Lavorato, A Lebeau, M Lebedev, A Lebrun, P Lecomte, P Lecoq, P Le Coultre, P Lee, HJ Le Goff, JM Leiste, R Leonardi, E Levtchenko, P Li, C Lin, CH Lin, WT Linde, FL Lista, L Liu, ZA Lohmann, W Longo, E Lu, YS Lubelsmeyer, K Luci, C Luckey, D Luminari, L Lustermann, W Ma, WG Maity, M Majumder, G Malgeri, L Malinin, A Mana, C Mangeol, D Marchesini, P Marian, G Martin, JP Marzano, F Massaro, GGG Mazumdar, K McNeil, RR Mele, S Merola, L Meschini, M Metzger, WJ von der Mey, M Migani, D Mihul, A Milcent, H Mirabelli, G Mnich, J Molnar, P Monteleoni, B Moulik, T Muanza, GS Muheim, F Muijs, AJM Nahn, S Napolitano, M Nessi-Tedaldi, F Newman, H Niessen, T Nippe, A Nisati, A Nowak, H Oh, YD Organtini, G Ostonen, R Palomares, C Pandoulas, D Paoletti, S Paolucci, P Park, HK Park, IH Pascale, G Passaleva, G Patricelli, S Paul, T Pauluzzi, M Paus, C Pauss, F Peach, D Pedace, M Pei, YJ Pensotti, S Perret-Gallix, D Petersen, B Petrak, S Piccolo, D Pieri, M Piroue, PA Pistolesi, E Plyaskin, V Pohl, M Pojidaev, V Postema, H Pothier, J Produit, N Prokofiev, D Quartieri, J Rahal-Callot, G Raja, N Rancoita, PG Raven, G Razis, P Ren, D Rescigno, M Reucroft, S van Rhee, T Riemann, S Riles, K Robohm, A Rodin, J Roe, BP Romero, L Rosier-Lees, S Roth, S Rubio, JA Ruschmeier, D Rykaczewski, H Sakar, S Salicio, J Sanchez, E Sanders, MP Sarakinos, ME Schafer, C Schegelsky, V Schmidt-Kaerst, S Schmitz, D Scholz, N Schopper, H Schotanus, DJ Schwenke, J Schwering, G Sciacca, C Sciarrino, D Servoli, L Shevchenko, S Shivarov, N Shoutko, V Shukla, J Shumilov, E Shvorob, A Siedenburg, T Son, D Smith, B Spillantini, P Steuer, M Stickland, DP Stone, A Stone, H Stoyanov, B Straessner, A Sudhakar, K Sultanov, G Sun, LZ Suter, H Swain, JD Szillasi, Z Tang, XW Tauscher, L Taylor, L Timmermans, C Ting, SCC Ting, SM Tonwar, SC Toth, J Tully, C Tung, KL Uchida, Y Ulbricht, J Valente, E Vesztergombi, G Vetlitsky, I Viertel, G Villa, S Vivargent, M Vlachos, S Vogel, H Vogt, H Vorobiev, I Vorobyov, AA Vorvolakos, A Wadhwa, M Wallraff, W Wang, JC Wang, XL Wang, ZM Weber, A Wilkens, H Wu, SX Wynhoff, S Xia, L Xu, ZZ Yang, BZ Yang, CG Yang, HJ Yang, M Ye, JB Yeh, SC You, JM Zalite, A Zalite, Y Zemp, P Zeng, Y Zhang, ZP Zhu, GY Zhu, RY Zichichi, A Ziegler, F Zilizi, G AF Acciarri, M Achard, P Adriani, O Aguilar-Benitez, M Alcaraz, J Alemanni, G Allaby, J Aloisio, A Alviggi, MG Ambrosi, G Anderhub, H Andreev, VP Angelescu, T Anselmo, F Arefiev, A Azemoon, T Aziz, T Bagnaia, P Baksay, L Balandras, A Ball, RC Banerjee, S Banerjee, S Banicz, K Barczyk, A Barillere, R Barone, L Bartalini, P Basile, M Battiston, R Bay, A Becattini, F Becker, U Behner, F Berdugo, J Berges, P Bertucci, B Betev, BL Bhattacharya, S Biasini, M Biland, A Blaising, JJ Blyth, SC Bobbink, GJ Bock, R Bohm, A Boldizsar, L Borgia, B Bourilkov, D Bourquin, M Braccini, S Branson, JG Brigljevic, V Brochu, F Buffini, A Buijs, A Burger, JD Burger, WJ Busenitz, J Button, A Cai, XD Campanelli, M Capell, M Romeo, GC Carlino, G Cartacci, AM Casaus, J Castellini, G Cavallari, F Cavallo, N Cecchi, C Cerrada, M Cesaroni, F Chamizo, M Chang, YH Chaturvedi, UK Chemarin, M Chen, A Chen, G Chen, GM Chen, HF Chen, HS Chereau, X Chiefari, G Cifarelli, L Cindolo, F Civinini, C Clare, I Clare, R Coignet, G Colijn, AP Colino, N Costantini, S Cotorobai, F de la Cruz, B Csilling, A Dai, TS van Dalen, JA D'Alessandro, R de Asmundis, R Deglon, P Degre, A Deiters, K della Volpe, D Denes, P DeNotaristefani, F De Salvo, A Diemoz, M van Dierendonck, D Di Lodovico, F Dionisi, C Dittmar, M Dominguez, A Doria, A Dova, MT Duchesneau, D Dufournand, D Duinker, P Duran, I El Mamouni, H Engler, A Eppling, FJ Erne, FC Extermann, P Fabre, M Faccini, R Falagan, MA Falciano, S Favara, A Fay, J Fedin, O Felcini, M Ferguson, T Ferroni, F Fesefeldt, H Fiandrini, E Field, JH Filthaut, F Fisher, PH Fisk, I Forconi, G Fredj, L Freudenreich, K Furetta, C Galaktionov, Y Ganguli, SN Garcia-Abia, P Gataullin, M Gau, SS Gentile, S Gheordanescu, N Giagu, S Goldfarb, S Gong, ZF Gruenewald, MW van Gulik, R Gupta, VK Gurtu, A Gutay, LJ Haas, D Hartmann, B Hasan, A Hatzifotiadou, D Hebbeker, T Herve, A Hidas, P Hirschfelder, J Hofer, H Holzner, G Hoorani, H Hou, SR Iashvili, I Jin, BN Jones, LW de Jong, P Josa-Mutuberria, I Khan, RA Kamrad, D Kapustinsky, JS Kaur, M Kienzle-Focacci, MN Kim, D Kim, DH Kim, JK Kim, SC Kinnison, WW Kirkby, J Kiss, D Kittel, W Klimentov, A Konig, AC Kopp, A Korolko, I Koutsenko, V Kraemer, RW Krenz, W Kunin, A Lacentre, P de Guevara, PL Laktineh, I Landi, G Lapoint, C Lassila-Perini, K Laurikainen, P Lavorato, A Lebeau, M Lebedev, A Lebrun, P Lecomte, P Lecoq, P Le Coultre, P Lee, HJ Le Goff, JM Leiste, R Leonardi, E Levtchenko, P Li, C Lin, CH Lin, WT Linde, FL Lista, L Liu, ZA Lohmann, W Longo, E Lu, YS Lubelsmeyer, K Luci, C Luckey, D Luminari, L Lustermann, W Ma, WG Maity, M Majumder, G Malgeri, L Malinin, A Mana, C Mangeol, D Marchesini, P Marian, G Martin, JP Marzano, F Massaro, GGG Mazumdar, K McNeil, RR Mele, S Merola, L Meschini, M Metzger, WJ von der Mey, M Migani, D Mihul, A Milcent, H Mirabelli, G Mnich, J Molnar, P Monteleoni, B Moulik, T Muanza, GS Muheim, F Muijs, AJM Nahn, S Napolitano, M Nessi-Tedaldi, F Newman, H Niessen, T Nippe, A Nisati, A Nowak, H Oh, YD Organtini, G Ostonen, R Palomares, C Pandoulas, D Paoletti, S Paolucci, P Park, HK Park, IH Pascale, G Passaleva, G Patricelli, S Paul, T Pauluzzi, M Paus, C Pauss, F Peach, D Pedace, M Pei, YJ Pensotti, S Perret-Gallix, D Petersen, B Petrak, S Piccolo, D Pieri, M Piroue, PA Pistolesi, E Plyaskin, V Pohl, M Pojidaev, V Postema, H Pothier, J Produit, N Prokofiev, D Quartieri, J Rahal-Callot, G Raja, N Rancoita, PG Raven, G Razis, P Ren, D Rescigno, M Reucroft, S van Rhee, T Riemann, S Riles, K Robohm, A Rodin, J Roe, BP Romero, L Rosier-Lees, S Roth, S Rubio, JA Ruschmeier, D Rykaczewski, H Sakar, S Salicio, J Sanchez, E Sanders, MP Sarakinos, ME Schafer, C Schegelsky, V Schmidt-Kaerst, S Schmitz, D Scholz, N Schopper, H Schotanus, DJ Schwenke, J Schwering, G Sciacca, C Sciarrino, D Servoli, L Shevchenko, S Shivarov, N Shoutko, V Shukla, J Shumilov, E Shvorob, A Siedenburg, T Son, D Smith, B Spillantini, P Steuer, M Stickland, DP Stone, A Stone, H Stoyanov, B Straessner, A Sudhakar, K Sultanov, G Sun, LZ Suter, H Swain, JD Szillasi, Z Tang, XW Tauscher, L Taylor, L Timmermans, C Ting, SCC Ting, SM Tonwar, SC Toth, J Tully, C Tung, KL Uchida, Y Ulbricht, J Valente, E Vesztergombi, G Vetlitsky, I Viertel, G Villa, S Vivargent, M Vlachos, S Vogel, H Vogt, H Vorobiev, I Vorobyov, AA Vorvolakos, A Wadhwa, M Wallraff, W Wang, JC Wang, XL Wang, ZM Weber, A Wilkens, H Wu, SX Wynhoff, S Xia, L Xu, ZZ Yang, BZ Yang, CG Yang, HJ Yang, M Ye, JB Yeh, SC You, JM Zalite, A Zalite, Y Zemp, P Zeng, Y Zhang, ZP Zhu, GY Zhu, RY Zichichi, A Ziegler, F Zilizi, G CA L3 Collaboration TI Inclusive charm production in two-photon collisions at LEP SO PHYSICS LETTERS B LA English DT Article ID HEAVY-QUARK PRODUCTION; LUND MONTE-CARLO; 2-PHOTON PROCESSES; CROSS-SECTION; JET FRAGMENTATION; PAIR PRODUCTION; L3 EXPERIMENT; E+E-PHYSICS; DETECTOR; ENERGIES AB The cross section of charm production in gamma gamma collisions sigma(e(+)e(-) --> e(+)e(-)c (c) over bar X) is measured at LEP with the L3 detector at centre-of-mass energies from 91 GeV to 183 GeV. Charmed hadrons are identified by electrons and muons from semileptonic decays. The direct process gamma gamma --> c (c) over bar is found to be insufficient to describe the data. The measured cross section values and event distributions require contributions from resolved processes, which are sensitive to the gluon density in the photon, (C) 1999 Published by Elsevier Science B.V. All rights reserved. C1 Ist Nazl Fis Nucl, Sez Milano, I-20133 Milan, Italy. Rhein Westfal TH Aachen, Inst Phys 1, D-52056 Aachen, Germany. Rhein Westfal TH Aachen, Inst Phys 3, D-52056 Aachen, Germany. NIKHEF H, Natl Lab High Energy Phys, NL-1009 DB Amsterdam, Netherlands. Univ Amsterdam, NL-1009 DB Amsterdam, Netherlands. Univ Michigan, Ann Arbor, MI 48109 USA. Lab Annecy Le Vieux Phys Particules, LAPP, IN2P3, CNRS, F-74941 Annecy Le Vieux, France. Univ Basel, Inst Phys, CH-4056 Basel, Switzerland. Louisiana State Univ, Baton Rouge, LA 70803 USA. Inst High Energy Phys, Beijing 100039, Peoples R China. Humboldt Univ, D-10099 Berlin, Germany. Univ Bologna, I-40126 Bologna, Italy. Ist Nazl Fis Nucl, Sez Bologna, I-40126 Bologna, Italy. Tata Inst Fundamental Res, Bombay 400005, Maharashtra, India. Northeastern Univ, Boston, MA 02115 USA. Inst Atom Phys, R-76900 Bucharest, Romania. Univ Bucharest, R-76900 Bucharest, Romania. Hungarian Acad Sci, Cent Res Inst Phys, H-1525 Budapest 114, Hungary. MIT, Cambridge, MA 02139 USA. Ist Nazl Fis Nucl, Sez Firenze, I-50125 Florence, Italy. Univ Florence, I-50125 Florence, Italy. CERN, European Lab Particle Phys, CH-1211 Geneva 23, Switzerland. Univ Geneva, CH-1211 Geneva 4, Switzerland. Univ Sci & Technol China, Hefei 230029, Anhui, Peoples R China. Res Inst High Energy Phys, SEFT, SF-00014 Helsinki, Finland. Univ Lausanne, CH-1015 Lausanne, Switzerland. Ist Nazl Fis Nucl, Sez Lecce, I-73100 Lecce, Italy. Univ Lecce, I-73100 Lecce, Italy. Los Alamos Natl Lab, Los Alamos, NM 87544 USA. Univ Lyon 1, CNRS, IN2P3, Inst Phys Nucl, F-69622 Villeurbanne, France. CIEMAT, E-28040 Madrid, Spain. Ist Nazl Fis Nucl, Sez Milano, I-20133 Milan, Italy. Inst Theoret & Expt Phys, Moscow 117259, Russia. Ist Nazl Fis Nucl, Sez Napoli, I-80125 Naples, Italy. Univ Naples Federico II, I-80125 Naples, Italy. Univ Cyprus, Dept Nat Sci, Nicosia, Cyprus. Catholic Univ Nijmegen, NL-6525 ED Nijmegen, Netherlands. Natl Inst Nucl Phys & High Energy Phys, NL-6525 ED Nijmegen, Netherlands. CALTECH, Pasadena, CA 91125 USA. Ist Nazl Fis Nucl, Sez Perugia, I-06100 Perugia, Italy. Univ Perugia, I-06100 Perugia, Italy. Carnegie Mellon Univ, Pittsburgh, PA 15213 USA. Princeton Univ, Princeton, NJ 08544 USA. Ist Nazl Fis Nucl, Sez Roma, I-00185 Rome, Italy. Univ Roma La Sapienza, I-00185 Rome, Italy. Inst Phys Nucl, St Petersburg, Russia. Univ Salerno, I-84100 Salerno, Italy. Ist Nazl Fis Nucl, I-84100 Salerno, Italy. Univ Calif San Diego, San Diego, CA 92093 USA. Univ Santiago, Dept Fis Particulas Elementales, E-15706 Santiago, Spain. Bulgarian Acad Sci, Cent Lab Mechatron & Instrumentat, BU-1113 Sofia, Bulgaria. Korea Adv Inst Sci & Technol, Ctr High Energy Phys, Taejon 305701, South Korea. Univ Alabama, Tuscaloosa, AL 35486 USA. Univ Utrecht, NL-3584 CB Utrecht, Netherlands. NIKHEF H, NL-3584 CB Utrecht, Netherlands. Purdue Univ, W Lafayette, IN 47907 USA. Paul Scherrer Inst, CH-5232 Villigen, Switzerland. DESY, Inst Hochenergiephys, D-15738 Zeuthen, Germany. Swiss Fed Inst Technol, CH-8093 Zurich, Switzerland. Univ Hamburg, D-22761 Hamburg, Germany. Natl Cent Univ, Chungli 32054, Taiwan. Natl Tsing Hua Univ, Dept Phys, Hsinchu, Taiwan. RP Acciarri, M (reprint author), Ist Nazl Fis Nucl, Sez Milano, Via Celoria 16, I-20133 Milan, Italy. RI Fiandrini, Emanuele/C-4549-2008; Cerrada, Marcos/J-6934-2014; Lista, Luca/C-5719-2008; Josa, Isabel/K-5184-2014; de la Cruz, Begona/K-7552-2014; Kirkby, Jasper/A-4973-2012; Servoli, Leonello/E-6766-2012; Vogel, Helmut/N-8882-2014; Ferguson, Thomas/O-3444-2014; bertucci, bruna/J-5237-2012; Berdugo, Javier/A-2858-2015; D'Alessandro, Raffaello/F-5897-2015; Cavallo, Nicola/F-8913-2012; Achard, Pablo/C-2983-2009; Sanchez, Eusebio/H-5228-2015; Rancoita, Pier Giorgio/J-9896-2015; Hoorani, Hafeez/D-1791-2013; Palomares, Carmen/H-7783-2015; Fedin, Oleg/H-6753-2016; Roth, Stefan/J-2757-2016; Di Lodovico, Francesca/L-9109-2016; Yang, Haijun/O-1055-2015; OI Cerrada, Marcos/0000-0003-0112-1691; Kirkby, Jasper/0000-0003-2341-9069; Servoli, Leonello/0000-0003-1725-9185; Vogel, Helmut/0000-0002-6109-3023; Ferguson, Thomas/0000-0001-5822-3731; Berdugo, Javier/0000-0002-7911-8532; D'Alessandro, Raffaello/0000-0001-7997-0306; Castellini, Guido/0000-0002-0177-0643; Diemoz, Marcella/0000-0002-3810-8530; Doria, Alessandra/0000-0002-5381-2649; Sciacca, Crisostomo/0000-0002-8412-4072; Faccini, Riccardo/0000-0003-2613-5141; Della Volpe, Domenico/0000-0001-8530-7447; Bertucci, Bruna/0000-0001-7584-293X; Filthaut, Frank/0000-0003-3338-2247; Achard, Pablo/0000-0002-4865-3196; Sanchez, Eusebio/0000-0002-9646-8198; Rancoita, Pier Giorgio/0000-0002-1990-4283; Palomares, Carmen/0000-0003-4374-9065; Roth, Stefan/0000-0003-3616-2223; Di Lodovico, Francesca/0000-0003-3952-2175; Longo, Egidio/0000-0001-6238-6787; Ambrosi, Giovanni/0000-0001-6977-9559 NR 33 TC 29 Z9 29 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 EI 1873-2445 J9 PHYS LETT B JI Phys. Lett. B PD APR 29 PY 1999 VL 453 IS 1-2 BP 83 EP 93 DI 10.1016/S0370-2693(99)00274-9 PG 11 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 195JD UT WOS:000080246100011 ER PT J AU Acciarri, M Achard, P Adriani, O Aguilar-Benitez, M Alcaraz, J Alemanni, G Allaby, J Aloisio, A Alviggi, MG Ambrosi, G Anderhub, H Andreev, VP Angelescu, T Anselmo, F Arefiev, A Azemoon, T Aziz, T Bagnaia, P Baksay, L Balandras, A Ball, RC Banerjee, S Banerjee, S Banicz, K Barczyk, A Barillere, R Barone, L Bartalini, P Basile, M Battiston, R Bay, A Becattini, F Becker, U Behner, F Berdugo, J Berges, P Bertucci, B Betev, BL Bhattacharya, S Biasini, M Biland, A Blaising, JJ Blyth, SC Bobbink, GJ Bohm, A Boldizsar, L Borgia, B Bourilkov, D Bourquin, M Braccini, S Branson, JG Brigljevic, V Brochu, F Buffini, A Buijs, A Burger, JD Burger, WJ Busenitz, J Button, A Cai, XD Campanelli, M Capell, M Romeo, GC Carlino, G Cartacci, AM Casaus, J Castellini, G Cavallari, F Cavallo, N Cecchi, C Cerrada, M Cesaroni, F Chamizo, M Chang, YH Chaturvedi, UK Chemarin, M Chen, A Chen, G Chen, GM Chen, HF Chen, HS Chereau, X Chiefari, G Cifarelli, L Cindolo, F Civinini, C Clare, I Clare, R Coignet, G Colijn, AP Colino, N Costantini, S Cotorobai, F de la Cruz, B Csilling, A Dai, TS van Dalen, JA D'Alessandro, R de Asmundis, R Deglon, P Degre, A Deiters, K della Volpe, D Denes, P DeNotaristefani, F De Salvo, A Diemoz, M van Dierendonck, D Di Lodovico, F Dionisi, C Dittmar, M Dominguez, A Doria, A Dova, MT Duchesneau, D Dufournand, D Duinker, P Doria, A Dova, MT Duchesneau, D Dufournand, D Duinker, P Duran, I El Mamouni, H Engler, A Eppling, FJ Erne, FC Extermann, P Fabre, M Faccini, R Falagan, MA Falciano, S Favara, A Fay, J Fedin, O Felcini, M Ferguson, T Ferroni, F Fesefeldt, H Fiandrini, E Field, JH Filthaut, F Fisher, PH Fisk, I Forconi, G Fredj, L Freudenreich, K Furetta, C Galaktionov, Y Ganguli, SN Garcia-Abia, P Gataullin, M Gau, SS Gentile, S Gheordanescu, N Giagu, S Goldfarb, S Gong, ZF Gruenewald, MW van Gulik, R Gupta, VK Gurtu, A Gutay, LJ Haas, D Hasan, A Hatzifotiadou, D Hebbeker, T Herve, A Hidas, P Hirschfelder, J Hofer, H Holzner, G Hoorani, H Hou, SR Iashvili, I Jin, BN Jones, LW de Jong, P Josa-Mutuberria, I Kasser, A Khan, RA Kamrad, D Kapustinsky, JS Kaur, M Kienzle-Focacci, MN Kim, D Kim, DH Kim, JK Kim, SC Kinnison, WW Kirkby, J Kiss, D Kittel, W Klimentov, A Konig, AC Kopp, A Korolko, I Koutsenko, V Kraemer, RW Krenz, W Kunin, A Lacentre, P de Guevara, PL Laktineh, I Landi, G Lapoint, C Lassila-Perini, K Laurikainen, P Lavorato, A Lebeau, M Lebedev, A Lebrun, P Lecomte, P Lecoq, P Le Coultre, P Lee, HJ Le Goff, JM Leiste, R Leonardi, E Levtchenko, P Li, C Lin, CH Lin, WT Linde, FL Lista, L Liu, ZA Lohmann, W Longo, E Lu, YS Lubelsmeyer, K Luci, C Luckey, D Luminari, L Lustermann, W Ma, WG Maity, M Majumder, G Malgeri, L Malinin, A Mana, C Mangeol, D Marchesini, P Marian, G Martin, JP Marzano, F Massaro, GGG Mazumdar, K McNeil, RR Mele, S Merola, L Meschini, M Metzger, WJ von der Mey, M Mi, Y Migani, D Mihul, A Milcent, H Mirabelli, G Mnich, J Molnar, P Monteleoni, B Moulik, T Muanza, GS Muheim, F Muijs, AJM Nahn, S Napolitano, M Nessi-Tedaldi, F Newman, H Niessen, T Nippe, A Nisati, A Nowak, H Oh, YD Organtini, G Ostonen, R Palomares, C Pandoulas, D Paoletti, S Paolucci, P Park, HK Park, IH Pascale, G Passaleva, G Patricelli, S Paul, T Pauluzzi, M Paus, C Pauss, F Peach, D Pedace, M Pei, YJ Pensotti, S Perret-Gallix, D Petersen, B Petrak, S Piccolo, D Pieri, M Piroue, PA Pistolesi, E Plyaskin, V Pohl, M Pojidaev, V Postema, H Pothier, J Produit, N Prokofiev, D Quartieri, J Rahal-Callot, G Raja, N Rancoita, PG Raven, G Razis, P Ren, D Rescigno, M Reucroft, S van Rhee, T Riemann, S Riles, K Robohm, A Robin, J Roe, BP Romero, L Rosier-Lees, S Rosselet, P Rubio, JA Ruschmeier, D Rykaczewski, H Sakar, S Salicio, J Sanchez, E Sanders, MP Sarakinos, ME Schafer, C Schegelsky, V Schmidt-Kaerst, S Schmitz, D Scholz, N Schopper, H Schotanus, DJ Schwenke, J Schwering, G Sciacca, C Sciarrino, D Servoli, L Shevchenko, S Shivarov, N Shoutko, V Shukla, J Shumilov, E Shvorob, A Siedenburg, T Son, D Smith, B Spillantini, P Steuer, M Stickland, DP Stone, A Stone, H Stoyanov, B Straessner, A Sudhakar, K Sultanov, G Sun, LZ Suter, H Swain, JD Szillasi, Z Tang, XW Tauscher, L Taylor, L Timmermans, C Ting, SCC Ting, SM Tonwar, SC Toth, J Tully, C Tung, KL Uchida, Y Ulbricht, J Valente, E Vesztergombi, G Vetlitsky, I Viertel, G Villa, S Vivargent, M Vlachos, S Vogel, H Vogt, H Vorobiev, I Vorobyov, AA Vorvolakos, A Wadhwa, M Wallraff, W Wang, JC Wang, XL Wang, ZM Weber, A Weber, M Wienemann, P Wilkens, H Wu, SX Wynhoff, S Xia, L Xu, ZZ Yang, BZ Yang, CG Yang, HJ Yang, M Ye, JB Yeh, SC You, JM Zalite, A Zalite, Y Zemp, P Zhang, ZP Zhu, GY Zhu, RY Zichichi, A Ziegler, F Zilizi, G Zoller, M AF Acciarri, M Achard, P Adriani, O Aguilar-Benitez, M Alcaraz, J Alemanni, G Allaby, J Aloisio, A Alviggi, MG Ambrosi, G Anderhub, H Andreev, VP Angelescu, T Anselmo, F Arefiev, A Azemoon, T Aziz, T Bagnaia, P Baksay, L Balandras, A Ball, RC Banerjee, S Banerjee, S Banicz, K Barczyk, A Barillere, R Barone, L Bartalini, P Basile, M Battiston, R Bay, A Becattini, F Becker, U Behner, F Berdugo, J Berges, P Bertucci, B Betev, BL Bhattacharya, S Biasini, M Biland, A Blaising, JJ Blyth, SC Bobbink, GJ Bohm, A Boldizsar, L Borgia, B Bourilkov, D Bourquin, M Braccini, S Branson, JG Brigljevic, V Brochu, F Buffini, A Buijs, A Burger, JD Burger, WJ Busenitz, J Button, A Cai, XD Campanelli, M Capell, M Romeo, GC Carlino, G Cartacci, AM Casaus, J Castellini, G Cavallari, F Cavallo, N Cecchi, C Cerrada, M Cesaroni, F Chamizo, M Chang, YH Chaturvedi, UK Chemarin, M Chen, A Chen, G Chen, GM Chen, HF Chen, HS Chereau, X Chiefari, G Cifarelli, L Cindolo, F Civinini, C Clare, I Clare, R Coignet, G Colijn, AP Colino, N Costantini, S Cotorobai, F de la Cruz, B Csilling, A Dai, TS van Dalen, JA D'Alessandro, R de Asmundis, R Deglon, P Degre, A Deiters, K della Volpe, D Denes, P DeNotaristefani, F De Salvo, A Diemoz, M van Dierendonck, D Di Lodovico, F Dionisi, C Dittmar, M Dominguez, A Doria, A Dova, MT Duchesneau, D Dufournand, D Duinker, P Doria, A Dova, MT Duchesneau, D Dufournand, D Duinker, P Duran, I El Mamouni, H Engler, A Eppling, FJ Erne, FC Extermann, P Fabre, M Faccini, R Falagan, MA Falciano, S Favara, A Fay, J Fedin, O Felcini, M Ferguson, T Ferroni, F Fesefeldt, H Fiandrini, E Field, JH Filthaut, F Fisher, PH Fisk, I Forconi, G Fredj, L Freudenreich, K Furetta, C Galaktionov, Y Ganguli, SN Garcia-Abia, P Gataullin, M Gau, SS Gentile, S Gheordanescu, N Giagu, S Goldfarb, S Gong, ZF Gruenewald, MW van Gulik, R Gupta, VK Gurtu, A Gutay, LJ Haas, D Hasan, A Hatzifotiadou, D Hebbeker, T Herve, A Hidas, P Hirschfelder, J Hofer, H Holzner, G Hoorani, H Hou, SR Iashvili, I Jin, BN Jones, LW de Jong, P Josa-Mutuberria, I Kasser, A Khan, RA Kamrad, D Kapustinsky, JS Kaur, M Kienzle-Focacci, MN Kim, D Kim, DH Kim, JK Kim, SC Kinnison, WW Kirkby, J Kiss, D Kittel, W Klimentov, A Konig, AC Kopp, A Korolko, I Koutsenko, V Kraemer, RW Krenz, W Kunin, A Lacentre, P de Guevara, PL Laktineh, I Landi, G Lapoint, C Lassila-Perini, K Laurikainen, P Lavorato, A Lebeau, M Lebedev, A Lebrun, P Lecomte, P Lecoq, P Le Coultre, P Lee, HJ Le Goff, JM Leiste, R Leonardi, E Levtchenko, P Li, C Lin, CH Lin, WT Linde, FL Lista, L Liu, ZA Lohmann, W Longo, E Lu, YS Lubelsmeyer, K Luci, C Luckey, D Luminari, L Lustermann, W Ma, WG Maity, M Majumder, G Malgeri, L Malinin, A Mana, C Mangeol, D Marchesini, P Marian, G Martin, JP Marzano, F Massaro, GGG Mazumdar, K McNeil, RR Mele, S Merola, L Meschini, M Metzger, WJ von der Mey, M Mi, Y Migani, D Mihul, A Milcent, H Mirabelli, G Mnich, J Molnar, P Monteleoni, B Moulik, T Muanza, GS Muheim, F Muijs, AJM Nahn, S Napolitano, M Nessi-Tedaldi, F Newman, H Niessen, T Nippe, A Nisati, A Nowak, H Oh, YD Organtini, G Ostonen, R Palomares, C Pandoulas, D Paoletti, S Paolucci, P Park, HK Park, IH Pascale, G Passaleva, G Patricelli, S Paul, T Pauluzzi, M Paus, C Pauss, F Peach, D Pedace, M Pei, YJ Pensotti, S Perret-Gallix, D Petersen, B Petrak, S Piccolo, D Pieri, M Piroue, PA Pistolesi, E Plyaskin, V Pohl, M Pojidaev, V Postema, H Pothier, J Produit, N Prokofiev, D Quartieri, J Rahal-Callot, G Raja, N Rancoita, PG Raven, G Razis, P Ren, D Rescigno, M Reucroft, S van Rhee, T Riemann, S Riles, K Robohm, A Robin, J Roe, BP Romero, L Rosier-Lees, S Rosselet, P Rubio, JA Ruschmeier, D Rykaczewski, H Sakar, S Salicio, J Sanchez, E Sanders, MP Sarakinos, ME Schafer, C Schegelsky, V Schmidt-Kaerst, S Schmitz, D Scholz, N Schopper, H Schotanus, DJ Schwenke, J Schwering, G Sciacca, C Sciarrino, D Servoli, L Shevchenko, S Shivarov, N Shoutko, V Shukla, J Shumilov, E Shvorob, A Siedenburg, T Son, D Smith, B Spillantini, P Steuer, M Stickland, DP Stone, A Stone, H Stoyanov, B Straessner, A Sudhakar, K Sultanov, G Sun, LZ Suter, H Swain, JD Szillasi, Z Tang, XW Tauscher, L Taylor, L Timmermans, C Ting, SCC Ting, SM Tonwar, SC Toth, J Tully, C Tung, KL Uchida, Y Ulbricht, J Valente, E Vesztergombi, G Vetlitsky, I Viertel, G Villa, S Vivargent, M Vlachos, S Vogel, H Vogt, H Vorobiev, I Vorobyov, AA Vorvolakos, A Wadhwa, M Wallraff, W Wang, JC Wang, XL Wang, ZM Weber, A Weber, M Wienemann, P Wilkens, H Wu, SX Wynhoff, S Xia, L Xu, ZZ Yang, BZ Yang, CG Yang, HJ Yang, M Ye, JB Yeh, SC You, JM Zalite, A Zalite, Y Zemp, P Zhang, ZP Zhu, GY Zhu, RY Zichichi, A Ziegler, F Zilizi, G Zoller, M CA L3 Collaboration TI Heavy quarkonium production in Z decays SO PHYSICS LETTERS B LA English DT Article ID HADRONIC Z(0) DECAYS; J/PSI-PRODUCTION; UPSILON-PRODUCTION; FRAGMENTATION; CHARMONIUM; LEP; ANNIHILATION; COLLISIONS; TEVATRON; PHYSICS AB We report measurements of the inclusive production of heavy quarkonium states in Z decays based on the analysis of 3.6 million hadronic events collected by the L3 detector at LEP. The measurement of inclusive J production and an improved 95% confidence level upper limit on gamma production are presented. In addition, two independent measurements of the ratio, f(p), Of prompt J mesons to those from B decay are made using two different isolation cuts to separate prompt J mesons from J mesons produced in the decays of b hadrons. The results are: Br(Z --> J + X) = (3.21 +/- 0.21 (stat.)(-0.28)(+0.19) (sys.)) X 10(-3) Br(Z --> gamma(1S) + X) < 4.4 x 10(-5), f(p) = (7.1 +/- 2.1 (stat.) +/- 1.2 (sys.)(-0.8)(+1.5) (theo.)) X 10(-2). (C) 1999 Published by Elsevier Science B.V. All rights reserved. C1 Ist Nazl Fis Nucl, Sez Milano, I-20133 Milan, Italy. Rhein Westfal TH Aachen, Inst Phys 1, D-52056 Aachen, Germany. Rhein Westfal TH Aachen, Inst Phys 3, D-52056 Aachen, Germany. NIKHEF H, Natl Lab High Energy Phys, NL-1009 DB Amsterdam, Netherlands. Univ Amsterdam, NL-1009 DB Amsterdam, Netherlands. Univ Michigan, Ann Arbor, MI 48109 USA. Lab Annecy Le Vieux Phys Particules, LAPP, IN2P3, CNRS, F-74941 Annecy Le Vieux, France. Univ Basel, Inst Phys, CH-4056 Basel, Switzerland. Louisiana State Univ, Baton Rouge, LA 70803 USA. Inst High Energy Phys, Beijing 100039, Peoples R China. Humboldt Univ, D-10099 Berlin, Germany. Univ Bologna, I-40126 Bologna, Italy. Ist Nazl Fis Nucl, Sez Bologna, I-40126 Bologna, Italy. Tata Inst Fundamental Res, Bombay 400005, Maharashtra, India. Northeastern Univ, Boston, MA 02115 USA. Inst Atom Phys, R-76900 Bucharest, Romania. Univ Bucharest, R-76900 Bucharest, Romania. Hungarian Acad Sci, Cent Res Inst Phys, H-1525 Budapest 114, Hungary. MIT, Cambridge, MA 02139 USA. Ist Nazl Fis Nucl, Sez Firenze, I-50125 Florence, Italy. Univ Florence, I-50125 Florence, Italy. CERN, European Lab Particle Phys, CH-1211 Geneva 23, Switzerland. FBLJA Project, World Lab, CH-1211 Geneva 23, Switzerland. Univ Geneva, CH-1211 Geneva 4, Switzerland. Univ Sci & Technol China, USTC, Hefei 230029, Anhui, Peoples R China. Res Inst High Energy Phys, SEFT, SF-00014 Helsinki, Finland. Univ Lausanne, CH-1015 Lausanne, Switzerland. Ist Nazl Fis Nucl, Sez Lecce, I-73100 Lecce, Italy. Univ Lecce, I-73100 Lecce, Italy. Los Alamos Natl Lab, Los Alamos, NM 87544 USA. Univ Lyon 1, Inst Phys Nucl, IN2P3, CNRS, F-69622 Villeurbanne, France. CIEMAT, E-28040 Madrid, Spain. Inst Theoret & Expt Phys, Moscow 117259, Russia. Ist Nazl Fis Nucl, Sez Napoli, I-80125 Naples, Italy. Univ Naples Federico II, I-80125 Naples, Italy. Univ Cyprus, Dept Nat Sci, Nicosia, Cyprus. Catholic Univ Nijmegen, NL-6525 ED Nijmegen, Netherlands. Natl Inst Nucl Phys & High Energy Phys, NL-6525 ED Nijmegen, Netherlands. CALTECH, Pasadena, CA 91125 USA. Ist Nazl Fis Nucl, Sez Perugia, I-06100 Perugia, Italy. Univ Perugia, I-06100 Perugia, Italy. Carnegie Mellon Univ, Pittsburgh, PA 15213 USA. Princeton Univ, Princeton, NJ 08544 USA. Ist Nazl Fis Nucl, Sez Roma, I-00185 Rome, Italy. Univ Roma La Sapienza, I-00185 Rome, Italy. Russian Acad Sci, Inst Nucl Phys, St Petersburg, Russia. Univ Salerno, I-84100 Salerno, Italy. Ist Nazl Fis Nucl, I-84100 Salerno, Italy. Univ Calif San Diego, San Diego, CA 92093 USA. Univ Santiago, Dept Fis Particular Elementales, E-15706 Santiago, Spain. Bulgarian Acad Sci, Cent Lab Mechatron & Instrumentat, BU-1113 Sofia, Bulgaria. Korea Adv Inst Sci & Technol, Ctr High Energy Phys, Taejon 305701, South Korea. Univ Alabama, Tuscaloosa, AL 35486 USA. Univ Utrecht, NL-3584 CB Utrecht, Netherlands. NIKHEF H, NL-3584 CB Utrecht, Netherlands. Purdue Univ, W Lafayette, IN 47907 USA. Paul Scherrer Inst, CH-5232 Villigen, Switzerland. DESY, Inst Hochenergiephys, D-15738 Zeuthen, Germany. Swiss Fed Inst Technol, CH-8093 Zurich, Switzerland. Univ Hamburg, D-22761 Hamburg, Germany. Natl Cent Univ, Chungli 32054, Taiwan. Natl Tsing Hua Univ, Dept Phys, Hsinchu, Taiwan. RP Acciarri, M (reprint author), Ist Nazl Fis Nucl, Sez Milano, Via Celoria 16, I-20133 Milan, Italy. RI Fiandrini, Emanuele/C-4549-2008; Lista, Luca/C-5719-2008; Kirkby, Jasper/A-4973-2012; Servoli, Leonello/E-6766-2012; bertucci, bruna/J-5237-2012; Cavallo, Nicola/F-8913-2012; Ferguson, Thomas/O-3444-2014; Berdugo, Javier/A-2858-2015; D'Alessandro, Raffaello/F-5897-2015; Cerrada, Marcos/J-6934-2014; Josa, Isabel/K-5184-2014; de la Cruz, Begona/K-7552-2014; Vogel, Helmut/N-8882-2014; Achard, Pablo/C-2983-2009; Sanchez, Eusebio/H-5228-2015; Duran, Ignacio/H-7254-2015; Rancoita, Pier Giorgio/J-9896-2015; Hoorani, Hafeez/D-1791-2013; Palomares, Carmen/H-7783-2015; Fedin, Oleg/H-6753-2016; Di Lodovico, Francesca/L-9109-2016; Yang, Haijun/O-1055-2015; OI Kirkby, Jasper/0000-0003-2341-9069; Servoli, Leonello/0000-0003-1725-9185; Ferguson, Thomas/0000-0001-5822-3731; Berdugo, Javier/0000-0002-7911-8532; D'Alessandro, Raffaello/0000-0001-7997-0306; Cerrada, Marcos/0000-0003-0112-1691; Vogel, Helmut/0000-0002-6109-3023; Castellini, Guido/0000-0002-0177-0643; Diemoz, Marcella/0000-0002-3810-8530; Doria, Alessandra/0000-0002-5381-2649; Sciacca, Crisostomo/0000-0002-8412-4072; Faccini, Riccardo/0000-0003-2613-5141; Della Volpe, Domenico/0000-0001-8530-7447; Bertucci, Bruna/0000-0001-7584-293X; Filthaut, Frank/0000-0003-3338-2247; Achard, Pablo/0000-0002-4865-3196; Sanchez, Eusebio/0000-0002-9646-8198; Rancoita, Pier Giorgio/0000-0002-1990-4283; Palomares, Carmen/0000-0003-4374-9065; Di Lodovico, Francesca/0000-0003-3952-2175; Longo, Egidio/0000-0001-6238-6787; Ambrosi, Giovanni/0000-0001-6977-9559 NR 39 TC 13 Z9 13 U1 4 U2 8 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 EI 1873-2445 J9 PHYS LETT B JI Phys. Lett. B PD APR 29 PY 1999 VL 453 IS 1-2 BP 94 EP 106 DI 10.1016/S0370-2693(99)00280-4 PG 13 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 195JD UT WOS:000080246100012 ER PT J AU Hyman, JM Shashkov, M AF Hyman, JM Shashkov, M TI The orthogonal decomposition theorems for mimetic finite difference methods SO SIAM JOURNAL ON NUMERICAL ANALYSIS LA English DT Article DE discrete vector analysis; discrete orthogonal decomposition theorem; mimetic finite difference methods ID DISCRETIZATION; CONVERGENCE; PROJECTIONS; EQUATIONS; SUMMATION; STABILITY; SCHEME; GRIDS; PARTS; CURL AB Accurate discrete analogs of differential operators that satisfy the identities and theorems of vector and tensor calculus provide reliable finite difference methods for approximating the solutions to a wide class of partial differential equations. These methods mimic many fundamental properties of the underlying physical problem including conservation laws, symmetries in the solution, and the nondivergence of particular vector fields (i.e., they are divergence free) and should satisfy a discrete version of the orthogonal decomposition theorem. This theorem plays a fundamental role in the theory of generalized solutions and in the numerical solution of physical models, including the Navier-Stokes equations and in electrodynamics. We are deriving mimetic finite difference approximations of the divergence, gradient, and curl that satisfy discrete analogs of the integral identities satisfied by the differential operators. We first define the natural discrete divergence, gradient, and curl operators based on coordinate invariant definitions, such as Gauss's theorem, for the divergence. Next we use the formal adjoints of these natural operators to derive compatible divergence, gradient, and curl operators with complementary domains and ranges of values. In this paper we prove that these operators satisfy discrete analogs of the orthogonal decomposition theorem and demonstrate how a discrete vector can be decomposed into two orthogonal vectors in a unique way, satisfying a discrete analog of the formula (A) over right arrow grad phi + curl (B) over right arrow. We also present a numerical example to illustrate the numerical procedure and calculate the convergence rate of the method for a spiral vector field. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Hyman, JM (reprint author), Univ Calif Los Alamos Natl Lab, T-7,MS B284, Los Alamos, NM 87545 USA. NR 41 TC 68 Z9 69 U1 0 U2 2 PU SIAM PUBLICATIONS PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 USA SN 0036-1429 J9 SIAM J NUMER ANAL JI SIAM J. Numer. Anal. PD APR 29 PY 1999 VL 36 IS 3 BP 788 EP 818 DI 10.1137/S0036142996314044 PG 31 WC Mathematics, Applied SC Mathematics GA 197PA UT WOS:000080372600006 ER PT J AU Lohmann, U Feichter, J Chuang, CC Penner, JE AF Lohmann, U Feichter, J Chuang, CC Penner, JE TI Prediction of the number of cloud droplets in the ECHAM GCM SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID GENERAL-CIRCULATION MODEL; ANTHROPOGENIC SULFATE AEROSOLS; MICROWAVE IMAGER SSM/I; OPTICAL-THICKNESS; SULFUR CYCLE; LIQUID WATER; 3-DIMENSIONAL MODEL; CLIMATE MODEL; UNITED-STATES; SENSITIVITY AB In this paper a prognostic equation for the number of cloud droplets (CDNC) is introduced into the ECHAM general circulation model. The initial CDNC is based on the mechanistic model of Chuang and Penner [1995], providing a more realistical prediction of CDNC than the empirical method previously used. Cloud droplet nucleation is parameterized as a function of total aerosol number concentration, updraft velocity, and a shape parameter, which takes the aerosol composition and size distribution into account. The total number of aerosol particles is obtained as the sum of marine sulfate aerosols produced from dimethyl sulfide, hydrophylic organic and black carbon, submicron dust, and sea-salt aerosols. Anthropogenic sulfate aerosols only add mass to the preexisting aerosols but do not form new particles. The simulated annual mean liquid water path, column CDNC, and effective radius agree well with observations, as does the frequency distributions of column CDNC for clouds over oceans and the variations of cloud optical depth with effective radius. C1 Dalhousie Univ, Dept Phys, Atmospher Sci Program, Halifax, NS B3H 3J5, Canada. Max Planck Inst Meteorol, D-20146 Hamburg, Germany. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Michigan, Dept Atmospher Ocean & Space Sci, Ann Arbor, MI 48109 USA. RP Lohmann, U (reprint author), Dalhousie Univ, Dept Phys, Atmospher Sci Program, Halifax, NS B3H 3J5, Canada. EM Ulrike.Lohmann@Dal.Ca RI Penner, Joyce/J-1719-2012; chuang, cathy/H-4814-2012; Lohmann, Ulrike/B-6153-2009 OI Lohmann, Ulrike/0000-0001-8885-3785 NR 91 TC 199 Z9 201 U1 0 U2 17 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 APR 27 PY 1999 VL 104 IS D8 BP 9169 EP 9198 DI 10.1029/1999JD900046 PG 30 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 189UY UT WOS:000079925600006 ER PT J AU Greenwald, TJ Christopher, SA Chou, J Liljegren, JC AF Greenwald, TJ Christopher, SA Chou, J Liljegren, JC TI Intercomparison of cloud liquid water path derived from the GOES 9 imager and ground based microwave radiometers for continental stratocumulus SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID SOLAR-RADIATION MEASUREMENTS; GENERAL-CIRCULATION MODEL; EFFECTIVE PARTICLE RADIUS; SATELLITE MEASUREMENTS; OPTICAL-THICKNESS; CLIMATE; MICROPHYSICS; FIRE; CALIBRATION; RETRIEVALS AB Solar reflectance measurements (0.6 and 3.9 mu m) from 15-min Geostationary Operational Environmental Satellite (GOES) 9 imager data were used to estimate cloud liquid water path (LWP) for an extensive stratocumulus system over Oklahoma on May 2, 1996. The objective was to determine the consistency between these satellite estimates and retrievals from high temporal resolution (20 s) surface microwave radiometer (SMWR) measurements. The SMWRs were located at the Atmospheric Radiation Measurement (ARM) program cloud and radiation test bed (CART) sites at Morris and Purcell in Oklahoma. Results show that while the comparisons are in favorable agreement at both sites in the morning and early afternoon (root-mean-square difference of 17 g m(-2) and correlation of 0.94), large cloud LWP maxima in the midafternoon as measured by the SMWR at the Morris site are not captured by the satellite retrievals. On the basis of indirect evidence (in situ microphysical measurements were unavailable), it is hypothesized that the discrepancies may be the result of the formation of light drizzle in the middle to lower portions of the cloud, unseen at visible and near-infrared wavelengths from space but easily sensed by microwave radiometry. These results demonstrate that extra care must be taken in future efforts to validate satellite derived cloud properties on a routine basis using SMWR data. Additional information about the cloud microphysical properties may also be required to help properly interpret the comparisons, particularly in the later stages of development of stratocumulus. C1 Colorado State Univ, Cooperat Inst Res Atmosphere, Ft Collins, CO 80523 USA. Univ Alabama, Dept Atmospher Sci, Huntsville, AL 35807 USA. US DOE, Ames Lab, Ctr NDE, Ames, IA 50011 USA. RP Greenwald, TJ (reprint author), Colorado State Univ, Cooperat Inst Res Atmosphere, Ft Collins, CO 80523 USA. EM greenwald@cira.colostate.edu RI Christopher, Sundar/E-6781-2011 NR 39 TC 14 Z9 14 U1 0 U2 0 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 APR 27 PY 1999 VL 104 IS D8 BP 9251 EP 9260 DI 10.1029/1999JD900037 PG 10 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 189UY UT WOS:000079925600010 ER PT J AU Shao, XM Rhodes, CT Holden, DN AF Shao, XM Rhodes, CT Holden, DN TI RF radiation observations of positive cloud-to-ground flashes SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID COMMON PHYSICAL PROCESSES; RADIO INTERFEROMETRY; LIGHTNING PHENOMENA; INTRACLOUD; JAPAN AB During the summers of 1995 and 1996 we conducted broadband HF-UHF and narrowband VHF radio frequency (RF) observations of positive cloud-to-ground (+CG) flashes at Langmuir and Los Alamos laboratories, New Mexico. These observations indicate that positive leaders to ground produce no or very weak radiation from KF to UHF. The broadband system was able to record 2 ms data each time it was triggered. For a I-CG the system was usually triggered by the return stroke, and a 1 ms pretrigger period was coincident with the positive leader process. It was commonly observed that no or little radiation was associated with the leader process in the 1 ms pretrigger period. The narrowband VHF system employed a logarithmic power amplifier and recorded one 1 ms data each time it was triggered. The narrowband observations show that strong and often continuous radiation occurs at the beginning of the +CGs, but the radiation usually becomes intermittent and impulsive during the last few tens of milliseconds preceding the return strokes. The observations for most of the +CGs also show complete lack of radiation a few ms before the beginning of the return strokes, suggesting that the ongoing downward positive leaders were quiet at VHF, at least during the final few ms. The results of this study for natural positive leaders are in agreement with the results obtained from laboratory gap discharges and rocket-triggered lightning. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Shao, XM (reprint author), Los Alamos Natl Lab, NIS-1,MS D466, Los Alamos, NM 87545 USA. EM xshao@lanl.gov NR 29 TC 35 Z9 44 U1 2 U2 11 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 APR 27 PY 1999 VL 104 IS D8 BP 9601 EP 9608 DI 10.1029/1999JD900036 PG 8 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 189UY UT WOS:000079925600033 ER PT J AU Frink, LJD van Swol, F AF Frink, LJD van Swol, F TI Stress isotherms of porous thin materials: Theoretical predictions from a nonlocal density functional theory SO LANGMUIR LA English DT Article ID FLUID-WALL INTERFACE; SOLVATION FORCES; COMPUTER-SIMULATION; DRYING TRANSITIONS AB Recent beam-bending (EB) experiments of microporous films with very small pores have shown that the fluid confined in these pores exhibits monotonic compressive stresses as the relative pressure is varied! from vacuum, to saturation (relative vapor pressure; p/p(0) = 1). The variation of the stress near saturation is found to be linear in ln(p) and given by the saturated liquid density rho(I) to within 20%. Capillary condensed fluids are traditionally described by the Laplace-Kelvin (LK) theory. LK theory correctly predicts the slope of the stress near saturation to be rho(I), but it also predicts that the stress should be zero at saturation and tensile between saturation and the capillary transition pressure;Hence, LK theory does not capture the monotonic compressive stress observed in BE experiments. This report describes the results of density functional theory calculations for a simple fluid confined to a slit pore network. We show how the presence of even a small amount of polydispersity in pore size leads to both a monotonic compressive stress as well as the observed LK slope. C1 Sandia Natl Labs, Mat Simulat Sci Dept, Albuquerque, NM 87185 USA. Sandia Natl Labs, Theoret & Computat Mat Modeling Dept, Albuquerque, NM 87185 USA. Univ New Mexico, Dept Chem Engn, Appl Mat Lab, Albuquerque, NM 87131 USA. RP Frink, LJD (reprint author), Sandia Natl Labs, Mat Simulat Sci Dept, POB 5800, Albuquerque, NM 87185 USA. NR 12 TC 13 Z9 13 U1 1 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0743-7463 J9 LANGMUIR JI Langmuir PD APR 27 PY 1999 VL 15 IS 9 BP 3296 EP 3301 DI 10.1021/la981584+ PG 6 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA 192YG UT WOS:000080106900042 ER PT J AU Detours, V Perelson, AS AF Detours, V Perelson, AS TI Explaining high alloreactivity as a quantitative consequence of affinity-driven thymocyte selection SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article ID T-CELL-RECEPTOR; MAJOR HISTOCOMPATIBILITY COMPLEX; MHC CLASS-I; SINGLE MHC/PEPTIDE LIGAND; POSITIVE SELECTION; THYMIC SELECTION; NEGATIVE SELECTION; PEPTIDE COMPLEXES; CLONAL DELETION; MOLECULAR-BASIS AB Interactions between alpha beta T cell receptors and peptides bound to molecules encoded by the MHC genes underly T cell activation. More than 1% of T cells are activated by foreign (allogenic) MHC molecules, a phenomenon called alloreactivity. Reconciling the high frequency of alloreactivity with the fact that only 1 T cell in 10(4)-10(6) responds to a given foreign antigen presented on self MHC has been a longstanding puzzle. We show, by using a quantitative model, that this difference follows from the affinity model of T cell selection. Further, we demonstrate that highly alloreactive pre- and post-selection repertoires can be obtained without assuming germline bias of T cell receptors toward recognition of allele-specific MHC residues. It has been proposed that alloreactivity occurs because self and foreign MHCs bind different subsets of self peptides or alter their conformation differently. We find that such effects decrease rather than increase alloreactivity. Overall, our results show that the affinity model of T cell selection can quantitatively explain both self MHC restriction and high alloreactivity. C1 Univ Calif Los Alamos Natl Lab, Ctr Nonlinear Studies, Los Alamos, NM 87545 USA. Santa Fe Inst, Santa Fe, NM 87501 USA. RP Detours, V (reprint author), Univ Calif Los Alamos Natl Lab, Ctr Nonlinear Studies, MS K710, Los Alamos, NM 87545 USA. FU NCRR NIH HHS [RR06555]; NIAID NIH HHS [AI28433] NR 73 TC 26 Z9 27 U1 0 U2 0 PU NATL ACAD SCIENCES PI WASHINGTON PA 2101 CONSTITUTION AVE NW, WASHINGTON, DC 20418 USA SN 0027-8424 J9 P NATL ACAD SCI USA JI Proc. Natl. Acad. Sci. U. S. A. PD APR 27 PY 1999 VL 96 IS 9 BP 5153 EP 5158 DI 10.1073/pnas.96.9.5153 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 193HQ UT WOS:000080130200076 PM 10220434 ER PT J AU Cagle, DW Kennel, SJ Mirzadeh, S Alford, JM Wilson, LJ AF Cagle, DW Kennel, SJ Mirzadeh, S Alford, JM Wilson, LJ TI In vivo studies of fullerene-based materials using endohedral metallofullerene radiotracers SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article ID WATER-SOLUBLE FULLERENE; BONE TARGETED DRUGS; HYDROXYAPATITE AFFINITY; C-60; ACID; LA-AT-C-82; COMPLEXES; HO-166; ESR; ACTIVATION AB Biodistribution studies of a water-soluble radioactive metallofullerene compound have been conducted using BALB/c mice. To this end, a sample containing Ho-x@C-82 (x = 1, 2) was purified and derivatized to prepare the water-soluble metallofullerol, Ho-x@C-82(OH)(y). This metallofullerol was then neutron-activated (Ho-165[n,gamma]Ho-166) to prepare the Ho-166(x)@C-82(OH)(y) analog as a radiotracer, which was monitored, after intravenous administration, for up to 48 hours by using dissection radioanalysis, and its biodistribution was compared with a control compound, Na-2[Ho-166(DTPA) (H2O)]. Results showed selective localization of the Ho-166(x)@C-82(OH)(y) tracer in the liver but with slow clearance, as well as uptake by bone without clearance. In contrast, excretion of the control compound was nearly quantitative after 1 hour. The fate of Ho-166 was also explored by a metabolism study of Ho-166(x)@C-82(OH)(y) in Fischer rats. Results indicated 20% excretion of intact Ho-166(x)@C-82(OH)(y) within 5 days. The present findings demonstrate the feasibility of using water-solubilized metallofullerene radiotracers to monitor the fate of fullerene-based materials in animals, and suggest that water-solubilized fullerene materials, in general, may be useful components in drug design. C1 Rice Univ, Dept Chem, Houston, TX 77251 USA. Rice Univ, Ctr Nanoscale Sci & Technol, Houston, TX 77251 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. TDA Res, Wheat Ridge, CO USA. RP Wilson, LJ (reprint author), Rice Univ, Dept Chem, MS-60,POB 1892, Houston, TX 77251 USA. EM durango@ruf.rice.edu NR 63 TC 210 Z9 222 U1 3 U2 43 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 APR 27 PY 1999 VL 96 IS 9 BP 5182 EP 5187 DI 10.1073/pnas.96.9.5182 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 193HQ UT WOS:000080130200082 PM 10220440 ER PT J AU Hsu, L Walukiewicz, W AF Hsu, L Walukiewicz, W TI Theoretical transport studies of p-type GaN/AlGaN modulation-doped heterostructures SO APPLIED PHYSICS LETTERS LA English DT Article ID FIELD-EFFECT TRANSISTORS; ELECTRON-MOBILITY; ALGAAS; CHARGE; MBE; GAS AB We have calculated hole transfer and low-temperature mobilities in p-type GaN/AlGaN modulation-doped heterostructures. Although substantial p-type conduction is difficult to achieve in bulk nitrides, the strain-induced polarization field can greatly enhance the transfer of holes from relatively deep Mg acceptors in the AlGaN barrier into the GaN well. The calculations predict formation of a two-dimensional hole gas with densities greater than 10(12) cm(-2) and with low-temperature mobilities in excess of 10(4) cm(2)/V s. (C) 1999 American Institute of Physics. [S0003-6951(99)01717-9]. C1 Carnegie Mellon Univ, Ctr Innovat Learning, Pittsburgh, PA 15213 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Hsu, L (reprint author), Carnegie Mellon Univ, Ctr Innovat Learning, Pittsburgh, PA 15213 USA. NR 14 TC 27 Z9 28 U1 1 U2 11 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD APR 26 PY 1999 VL 74 IS 17 BP 2405 EP 2407 DI 10.1063/1.123897 PG 3 WC Physics, Applied SC Physics GA 188PD UT WOS:000079855900001 ER PT J AU Brown, IG Monteiro, OR Bilek, MMM AF Brown, IG Monteiro, OR Bilek, MMM TI High voltage sheath behavior in a drifting plasma SO APPLIED PHYSICS LETTERS LA English DT Article ID IMMERSION ION-IMPLANTATION; SURFACE MODIFICATION; PROFILES; MODEL AB We describe a simple experiment in which a high voltage substrate is immersed in a streaming, vacuum-arc-produced, titanium plasma. We show that high substrate voltages that are orders of magnitude greater than the electron temperature can be sustained, effectively on a direct current basis, by a well-rounded substrate (no sharp points or edges) immersed in the plasma stream, for the case of a plasma with density not too low (greater than about 10(9) cm(-3)) and with drift velocity that is equal to or greater than the sheath propagation speed, typically of order the ion acoustic speed. This result is significant not only from a basic plasma physics perspective, but also for the technology of carrying out plasma immersion surface processing. (C) 1999 American Institute of Physics. [S0003-6951(99)03517-2]. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Brown, IG (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. NR 21 TC 21 Z9 22 U1 1 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD APR 26 PY 1999 VL 74 IS 17 BP 2426 EP 2428 DI 10.1063/1.123869 PG 3 WC Physics, Applied SC Physics GA 188PD UT WOS:000079855900008 ER PT J AU Stemmer, S Streiffer, SK Browning, ND Kingon, AI AF Stemmer, S Streiffer, SK Browning, ND Kingon, AI TI Accommodation of nonstoichiometry in (100) fiber-textured (BaxSr1-x)Ti1-yO3+z thin films grown by chemical vapor deposition SO APPLIED PHYSICS LETTERS LA English DT Article ID ELECTRON-ENERGY-LOSS; RANDOM-ACCESS MEMORIES; X-RAY-ABSORPTION; DIELECTRIC-PROPERTIES; BARIUM-TITANATE; SPECTROSCOPY; TEMPERATURE; SRTIO3; (BA AB We have investigated the microstructural accommodation of nonstoichiometry in (BaxSr1-x)Ti1+yO3+z thin films grown by chemical vapor deposition. Films with y=0.04 and y=0.15 were studied by high-spatial resolution electron energy-loss spectroscopy, revealing changes in chemistry and local atomic environment both at grain boundaries and within grains as a function of titanium content. We find that excess titanium in the samples with y=0.15 segregates to the grain boundaries in addition to being partially accommodated in the grain interior. (C) 1999 American Institute of Physics. [S0003-6951(99)02217-2]. C1 Univ Illinois, Dept Phys, Chicago, IL 60607 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. N Carolina State Univ, Raleigh, NC 27695 USA. RP Stemmer, S (reprint author), Univ Illinois, Dept Phys, Chicago, IL 60607 USA. RI Streiffer, Stephen/A-1756-2009; Stemmer, Susanne/H-6555-2011; OI Stemmer, Susanne/0000-0002-3142-4696; Browning, Nigel/0000-0003-0491-251X NR 24 TC 39 Z9 43 U1 0 U2 5 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD APR 26 PY 1999 VL 74 IS 17 BP 2432 EP 2434 DI 10.1063/1.123871 PG 3 WC Physics, Applied SC Physics GA 188PD UT WOS:000079855900010 ER PT J AU Agarwal, A Gossmann, HJ Eaglesham, DJ Herner, SB Fiory, AT Haynes, TE AF Agarwal, A Gossmann, HJ Eaglesham, DJ Herner, SB Fiory, AT Haynes, TE TI Boron-enhanced diffusion of boron from ultralow-energy ion implantation SO APPLIED PHYSICS LETTERS LA English DT Article ID SILICON; SI AB We have investigated the diffusion enhancement mechanism of boron-enhanced diffusion (BED), wherein boron diffusivity is enhanced four to five times over the equilibrium diffusivity at 1050 degrees C in the proximity of a silicon layer containing a high boron concentration. It is demonstrated that BED is driven by excess interstitials injected from the high boron concentration layer during annealing. For evaporated layers, BED is observed above a threshold boron concentration between 1% and 10%, though it appears to be closer to 1% for B-implanted layers. For sub-keV B implants above the threshold, BED dominates over the contribution from transient-enhanced diffusion to junction depth. For 0.5 keV B, this threshold implantation dose lies between 3 x 10(14) and 1 x 10(15) cm(-2). It is proposed that the excess interstitials responsible for BED are produced during the formation of a silicon boride phase in the high B concentration layers. (C) 1999 American Institute of Physics. [S0003-6951(99)02117-8]. C1 AT&T Bell Labs, Lucent Technol, Murray Hill, NJ 07974 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Agarwal, A (reprint author), Eaton Corp, Semicond Equipment Operat, 55 Cherry Hill Dr, Beverly, MA 01915 USA. RI Haynes, Tony/P-8932-2015 OI Haynes, Tony/0000-0003-2871-4745 NR 13 TC 70 Z9 70 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD APR 26 PY 1999 VL 74 IS 17 BP 2435 EP 2437 DI 10.1063/1.123872 PG 3 WC Physics, Applied SC Physics GA 188PD UT WOS:000079855900011 ER PT J AU Barnard, DJ AF Barnard, DJ TI Variation of nonlinearity parameter at low fundamental amplitudes SO APPLIED PHYSICS LETTERS LA English DT Article ID INCONEL-718 AB Recent harmonic generation measurements of the nonlinearity parameter beta in polycrystalline Cu-Al alloys have shown a transition to lower values at low fundamental amplitude levels. Values for bat high (>10 Angstrom) fundamental levels are in the range predicted by single-crystal second- and third-order elastic constants while lower fundamental levels (<4 Angstrom) produce values that are a fraction of those predicted. The effect is believed genuine and has been demonstrated recently in a commercial aluminum alloy by others. The source of the effect is unclear but initial results may require a reexamination of current methods for measurement of third-order elastic constants. (C) 1999 American Institute of Physics. [S0003-6951(99)00517-3]. C1 Iowa State Univ Sci & Technol, Ames Lab, US DOE, Met & Ceram Program, Ames, IA 50011 USA. RP Barnard, DJ (reprint author), Iowa State Univ Sci & Technol, Ames Lab, US DOE, Met & Ceram Program, Ames, IA 50011 USA. NR 13 TC 24 Z9 24 U1 4 U2 8 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD APR 26 PY 1999 VL 74 IS 17 BP 2447 EP 2449 DI 10.1063/1.123876 PG 3 WC Physics, Applied SC Physics GA 188PD UT WOS:000079855900015 ER PT J AU Su, DS Wei, SH AF Su, DS Wei, SH TI Transmission electron microscopy investigation and first-principles calculation of the phase stability in epitaxial CuInS2 and CuGaSe2 films SO APPLIED PHYSICS LETTERS LA English DT Article ID ORDER-DISORDER TRANSITION; SEMICONDUCTORS AB Ordering of metal atoms in CuInS2 and CuGaSe2 thin films grown by vapor-phase epitaxy on Si (001) and GaAs (001) substrates were studied using transmission electron microscopy and first-principles total energy calculations. Chalcopyrite and CuAu-like orderings of the metal atoms were observed coexisting in CuInS2 films, while only chalcopyrite ordering was found in CuGaSe2 films. First-principles total energy calculations find that the formation enthalpy difference between chalcopyrite and CuAu-like phases of CuInS2 is very small (2 meV/atom), while it is large for CuGaSe2 (9 meV/atom), indicating that the existence of CuAu-like phase in the nominally chalcopyrite semiconductors is controlled by bulk thermodynamics. (C) 1999 American Institute of Physics. [S0003-6951(99)02118-X]. C1 Humboldt Univ, Inst Phys, D-10115 Berlin, Germany. Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Su, DS (reprint author), Humboldt Univ, Inst Phys, Invalidenstr 110, D-10115 Berlin, Germany. EM shw@sst.nrel.gov NR 17 TC 42 Z9 42 U1 1 U2 13 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0003-6951 EI 1077-3118 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD APR 26 PY 1999 VL 74 IS 17 BP 2483 EP 2485 DI 10.1063/1.123014 PG 3 WC Physics, Applied SC Physics GA 188PD UT WOS:000079855900027 ER PT J AU Leung, K Wright, AF Stechel, EB AF Leung, K Wright, AF Stechel, EB TI Charge accumulation at a threading edge dislocation in gallium nitride SO APPLIED PHYSICS LETTERS LA English DT Article ID LIGHT-EMITTING-DIODES; CHEMICAL-VAPOR-DEPOSITION; MOLECULAR-DYNAMICS; GAN FILMS; SCATTERING; BLUE AB We have performed Monte Carlo calculations to determine the charge accumulation on threading edge dislocations in GaN as a function of the dislocation density and background dopant density. Four possible core structures have been examined, each of which produces defect levels in the gap and may therefore act as electron or hole traps. Our results indicate that charge accumulation, and the resulting electrostatic interactions, can change the relative stabilities of the different core structures. Structures having Ga and N vacancies at the dislocation core are predicted to be stable under nitrogen-rich and gallium-rich growth conditions, respectively. Due to dopant depletion at high dislocation density and the multitude of charge states, the line charge exhibits complex crossover behavior as the dopant and dislocation densities vary. (C) 1999 American Institute of Physics. [S0003-6951(99)00616-6]. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Ford Motor Co, Dearborn, MI 48121 USA. RP Sandia Natl Labs, MS 1421, Albuquerque, NM 87185 USA. RI Stechel, Ellen/B-1253-2012 NR 18 TC 116 Z9 119 U1 3 U2 32 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 APR 26 PY 1999 VL 74 IS 17 BP 2495 EP 2497 DI 10.1063/1.123018 PG 3 WC Physics, Applied SC Physics GA 188PD UT WOS:000079855900031 ER PT J AU Boettger, JC AF Boettger, JC TI Relativistic effects on the structural phase stability of molybdenum SO JOURNAL OF PHYSICS-CONDENSED MATTER LA English DT Article ID DOUGLAS-KROLL TRANSFORMATION; METALS; MO; ENERGY; CR; FORMALISM; SYSTEMS; STATE; ATOMS; 4D AB The relative stabilities of the fee, bcc, and hcp structures of molybdenum (Mo) are studied as functions of volume with both nonrelativistic and scalar-relativistic linear combinations of Gaussian-type orbitals (LCGTO) fitting function calculations. Relativity is shown to have a significant effect on the bcc-fce structural energy difference that first increases, then decreases, with pressure, but has only a negligible effect on the hcp-fcc structural energy difference. The scalar-relativistic bcc-fcc energy difference curve obtained here is in good agreement with an earlier fully relativistic calculation using the all-electron full-potential linear muffin-tin orbital method. Unlike previous theoretical work, this investigation finds no region of hcp phase stability at T = 0. Instead, the bcc phase transforms directly into the fee phase at a pressure of about 6.6 Mbar. C1 Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Boettger, JC (reprint author), Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. NR 39 TC 19 Z9 21 U1 0 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0953-8984 J9 J PHYS-CONDENS MAT JI J. Phys.-Condes. Matter PD APR 26 PY 1999 VL 11 IS 16 BP 3237 EP 3246 DI 10.1088/0953-8984/11/16/005 PG 10 WC Physics, Condensed Matter SC Physics GA 193UA UT WOS:000080154500005 ER PT J AU Mazonka, O Jarzynski, C Blocki, J AF Mazonka, O Jarzynski, C Blocki, J TI Computing probabilities of very rare events for Langevin processes: New method based on importance sampling (vol 641, pg 335, 1998) SO NUCLEAR PHYSICS A LA English DT Correction C1 Inst Nucl Studies, Swierk, Poland. Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM USA. RP Mazonka, O (reprint author), Inst Nucl Studies, Swierk, Poland. RI Jarzynski, Christopher/B-4490-2009 OI Jarzynski, Christopher/0000-0002-3464-2920 NR 2 TC 5 Z9 5 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9474 J9 NUCL PHYS A JI Nucl. Phys. A PD APR 26 PY 1999 VL 650 IS 4 BP 499 EP 500 PG 2 WC Physics, Nuclear SC Physics GA 196QP UT WOS:000080319300007 ER PT J AU Bern, Z Dixon, L Perelstein, M Rozowsky, JS AF Bern, Z Dixon, L Perelstein, M Rozowsky, JS TI Multi-leg one-loop gravity amplitudes from gauge theory SO NUCLEAR PHYSICS B LA English DT Review DE unitarity; cutting; supersymmetry; supergravity; one-loop ID YANG-MILLS THEORY; CONFORMAL FIELD-THEORIES; STRING-BASED METHODS; SELF-DUAL SECTOR; HELICITY AMPLITUDES; GLUON SCATTERING; QCD AMPLITUDES; DIMENSIONAL REGULARIZATION; COLLINEAR LIMITS; N=8 SUPERGRAVITY AB By exploiting relations between gravity and gauge theories, we present two infinite sequences of one-loop n-graviton scattering amplitudes: the 'maximally helicity-violating' amplitudes in N = 8 supergravity, and the 'all-plus' helicity amplitudes in gravity with any minimally coupled massless matter content. The all-plus amplitudes correspond to self-dual field configurations and vanish in supersymmetric theories. We make use of the tree-level Kawai-Lewellen-Tye (KLT) relations between open and closed string theory amplitudes, which in the low-energy limit imply relations between gravity and gauge theory tree amplitudes. For n less than or equal to 6, we determine the all-plus amplitudes explicitly from their unitarity cuts. The KLT relations, applied to the cuts, allow us to extend to gravity a previously found 'dimension-shifting' relation between (the cuts of) the all-plus amplitudes in gauge theory and the maximally helicity-violating amplitudes in N = 4 super-Yang-Mills theory. The gravitational version of the relation lets us determine the n less than or equal to 6 N = 8 supergravity amplitudes from the all-plus gravity amplitudes. We infer the two series of amplitudes for all n from their soft and collinear properties, which can also be derived from gauge theory using the KLT relations. (C) 1999 Published by Elsevier Science B.V. C1 Univ Calif Los Angeles, Dept Phys, Los Angeles, CA 90095 USA. Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. Univ Florida, Dept Phys, Inst Fundamental Theory, Gainesville, FL 32611 USA. RP Bern, Z (reprint author), Univ Calif Los Angeles, Dept Phys, Los Angeles, CA 90095 USA. NR 107 TC 156 Z9 156 U1 0 U2 4 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 APR 26 PY 1999 VL 546 IS 1-2 BP 423 EP 479 DI 10.1016/S0550-3213(99)00029-2 PG 57 WC Physics, Particles & Fields SC Physics GA 195XB UT WOS:000080276500021 ER PT J AU de Gouvea, A Murayama, H AF de Gouvea, A Murayama, H TI Establishing a nu(mu,tau) component in the solar neutrino flux SO PHYSICAL REVIEW LETTERS LA English DT Article ID DETECTOR AB We point out that the recoil electron kinetic energy spectra in the v-epsilon elastic scattering are different for incident nu(e) or nu(mu,tau), and hence one can in principle establish the existence of the nu(mu,tau) component in the solar neutrino flux by fitting the shape of the spectrum. This would be a new model-independent test of the solar neutrino oscillation in a single experiment, free from astrophysical and nuclear physics uncertainties. For the Be-7 neutrinos, it is possible to determine the nu(mu,tau) component at BOREXINO or KamLAND, if the background is sufficiently low. Note that this effect is different from the distortion in the incident neutrino energy spectrum, which has been discussed in the literature. C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Theoret Phys Grp, Berkeley, CA 94720 USA. RP de Gouvea, A (reprint author), Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. RI Murayama, Hitoshi/A-4286-2011 NR 19 TC 10 Z9 10 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 APR 26 PY 1999 VL 82 IS 17 BP 3392 EP 3395 DI 10.1103/PhysRevLett.82.3392 PG 4 WC Physics, Multidisciplinary SC Physics GA 189HW UT WOS:000079899900003 ER PT J AU Svensson, CE Rudolph, D Baktash, C Bentley, MA Cameron, JA Carpenter, MP Devlin, M Eberth, J Flibotte, S Galindo-Uribarri, A Hackman, G Haslip, DS Janssens, RVF LaFosse, DR Lampman, TJ Lee, IY Lerma, F Macchiavelli, AO Nieminen, JM Paul, SD Radford, DC Reiter, P Riedinger, LL Sarantites, DG Schaly, B Seweryniak, D Thelen, O Thomas, HG Waddington, JC Ward, D Weintraub, W Wilson, JN Yu, CH Afanasjev, AV Ragnarsson, I AF Svensson, CE Rudolph, D Baktash, C Bentley, MA Cameron, JA Carpenter, MP Devlin, M Eberth, J Flibotte, S Galindo-Uribarri, A Hackman, G Haslip, DS Janssens, RVF LaFosse, DR Lampman, TJ Lee, IY Lerma, F Macchiavelli, AO Nieminen, JM Paul, SD Radford, DC Reiter, P Riedinger, LL Sarantites, DG Schaly, B Seweryniak, D Thelen, O Thomas, HG Waddington, JC Ward, D Weintraub, W Wilson, JN Yu, CH Afanasjev, AV Ragnarsson, I TI Decay out of the doubly magic superdeformed band in the N=Z nucleus Zn-60 SO PHYSICAL REVIEW LETTERS LA English DT Article ID HIGHLY DEFORMED BANDS; ROTATIONAL BANDS; MASS REGION; EXCITATION-ENERGIES; HIGH-SPIN; YRAST; PB-194; PARITY; HG-194; STATES AB The doubly magic superdeformed band in the N = Z nucleus Zn-60 has been identified. Linking transitions connecting this band to the yrast line provide the first spin, parity, and excitation energy measurements for superdeformed states in the A similar to 60 region. The stretched-E2 character and relatively large B(E2) values of these transitions suggest a nonstatistical decay-out process. C1 McMaster Univ, Dept Phys & Astron, Hamilton, ON L8S 4M1, Canada. Univ Lund, Dept Phys, S-22100 Lund, Sweden. Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. Staffordshire Univ, Sch Sci, Stoke On Trent ST4 2DE, Staffs, England. Argonne Natl Lab, Argonne, IL 60439 USA. Washington Univ, Dept Chem, St Louis, MO 63130 USA. Univ Cologne, Inst Kernphys, D-50937 Cologne, Germany. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. Tech Univ Munich, Dept Phys, D-85747 Garching, Germany. Latvian Acad Sci, Nucl Res Ctr, LV-2169 Salaspils, Latvia. RP Svensson, CE (reprint author), McMaster Univ, Dept Phys & Astron, Hamilton, ON L8S 4M1, Canada. RI Rudolph, Dirk/D-4259-2009; radford, David/A-3928-2015; Carpenter, Michael/E-4287-2015; Devlin, Matthew/B-5089-2013 OI Rudolph, Dirk/0000-0003-1199-3055; Carpenter, Michael/0000-0002-3237-5734; Devlin, Matthew/0000-0002-6948-2154 NR 32 TC 98 Z9 98 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 APR 26 PY 1999 VL 82 IS 17 BP 3400 EP 3403 DI 10.1103/PhysRevLett.82.3400 PG 4 WC Physics, Multidisciplinary SC Physics GA 189HW UT WOS:000079899900005 ER PT J AU Laaziri, K Kycia, S Roorda, S Chicoine, H Robertson, JL Wang, J Moss, SC AF Laaziri, K Kycia, S Roorda, S Chicoine, H Robertson, JL Wang, J Moss, SC TI High resolution radial distribution function of pure amorphous silicon SO PHYSICAL REVIEW LETTERS LA English DT Article ID NEUTRON-DIFFRACTION; GERMANIUM; DENSITY; SI AB The structure factor S(Q) of high purity amorphous Si membranes prepared by ion implantation was measured over an extended Q range (0.03-55 A(-1)). Calculation of the first neighbor shell coordination (C-1) as a function of maximum Q indicates that measurement of S(Q) out to at least 40 Angstrom(-1) is required to reliably determine the radial distribution function (RDF). A 2% change in C-1 and subtle changes in the rest of the RDF were observed upon annealing, consistent with point defect removal. After annealing at 600 degrees C, C-1 = 3.88, which would explain why amorphous Si is less dense than crystalline Si. C1 Univ Montreal, Dept Phys, Grp Rech Phys & Technol Couches Minces, Montreal, PQ H3C 3J7, Canada. Cornell Univ, CHESS, Wilson Lab, Ithaca, NY 14853 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Univ Houston, Dept Phys, Houston, TX 77204 USA. RP Laaziri, K (reprint author), Univ Montreal, Dept Phys, Grp Rech Phys & Technol Couches Minces, CP 6128,Succursale Ctr Ville, Montreal, PQ H3C 3J7, Canada. RI Roorda, Sjoerd/N-2604-2014 NR 25 TC 151 Z9 151 U1 5 U2 102 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 APR 26 PY 1999 VL 82 IS 17 BP 3460 EP 3463 DI 10.1103/PhysRevLett.82.3460 PG 4 WC Physics, Multidisciplinary SC Physics GA 189HW UT WOS:000079899900020 ER PT J AU Galli, G Gygi, F Catellani, A AF Galli, G Gygi, F Catellani, A TI Quantum mechanical simulations of microfracture in a complex material SO PHYSICAL REVIEW LETTERS LA English DT Article ID AMORPHOUS-SILICON CARBIDE; MOLECULAR-DYNAMICS; FILMS AB Microfracture in an amorphous semiconductor was investigated by means of first-principles molecular dynamics. A numerical experiment was performed in which a sample of amorphous silicon carbide was subjected to uniaxial strain until failure occurred. The onset of fracture could be unequivocally related to the chemical properties of the constituent species. Rearrangements of atoms following failure indicated a tendency towards Si segregation at the surface. Hardness properties inferred from the stress-strain relationship agree well with experimental data. This type of quantum simulation also provides an unbiased method for generating models of surfaces of complex disordered materials. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. CNR, MASPEC, I-43001 Parma, Italy. RP Galli, G (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. OI Catellani, Alessandra/0000-0001-5197-7186 NR 12 TC 24 Z9 24 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 APR 26 PY 1999 VL 82 IS 17 BP 3476 EP 3479 DI 10.1103/PhysRevLett.82.3476 PG 4 WC Physics, Multidisciplinary SC Physics GA 189HW UT WOS:000079899900024 ER PT J AU Schenter, GK Kathmann, SM Garrett, BC AF Schenter, GK Kathmann, SM Garrett, BC TI Dynamical nucleation theory: A new molecular approach to vapor-liquid nucleation SO PHYSICAL REVIEW LETTERS LA English DT Article ID MONTE-CARLO SIMULATION; TRANSITION-STATE THEORY; PHASE NUCLEATION; PHYSICAL CLUSTERS; WATER AB A new theoretical approach is presented for vapor-phase nucleation. In contrast to previous molecular approaches to nucleation that focus on evaluating equilibrium distributions of clusters, we evaluate rate constants for cluster evaporation and condensation that are the elementary kinetic steps in the nucleation mechanism. The use of variational transition state theory to estimate the rate constants provides a consistent procedure for defining a unique value for the constraining volume of the physically consistent cluster. The theory is applied to evaporation of small water clusters. C1 Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Schenter, GK (reprint author), Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RI Garrett, Bruce/F-8516-2011; Schenter, Gregory/I-7655-2014 OI Schenter, Gregory/0000-0001-5444-5484 NR 22 TC 90 Z9 90 U1 2 U2 27 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD APR 26 PY 1999 VL 82 IS 17 BP 3484 EP 3487 DI 10.1103/PhysRevLett.82.3484 PG 4 WC Physics, Multidisciplinary SC Physics GA 189HW UT WOS:000079899900026 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 c-axis electronic Raman scattering in Bi2Sr2CaCu2O8+delta SO PHYSICAL REVIEW LETTERS LA English DT Article ID COPPER-OXIDE SUPERCONDUCTORS; SINGLE-CRYSTALS; PENETRATION DEPTH; CUPRATE SUPERCONDUCTORS; TUNNELING SPECTROSCOPY; TEMPERATURE-DEPENDENCE; GAP ANISOTROPY; PROBE; ELECTRODYNAMICS; FLUCTUATIONS AB We report on the c-axis-polarized electronic Raman scattering of Bi2Sr2CaCu2O8+delta single crystals with various oxygen concentrations. 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, a superconductivity-induced 2 Delta peak is observed for omega < 80 meV and the 2 Delta/k(B)T(c) value increases with decreasing hole doping. In particular, this A(Ig) 2 Delta peak energy, which is higher than that seen with inplane polarizations for all doping levels studied, signifies distinctly different dynamics of quasiparticles coated with out-of-plane polarization. C1 Univ Illinois, Dept Phys, Urbana, IL 61801 USA. Univ Illinois, Sci & Technol Ctr Superconduct, Urbana, IL 61801 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Argonne Natl Lab, Sci & Technol Ctr Supercond, Argonne, IL 60439 USA. AT&T Bell Labs, Lucent Technol, Murray Hill, NJ 07974 USA. RP Univ Illinois, Dept Phys, 1110 W Green St, Urbana, IL 61801 USA. NR 43 TC 25 Z9 25 U1 1 U2 3 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 APR 26 PY 1999 VL 82 IS 17 BP 3524 EP 3527 DI 10.1103/PhysRevLett.82.3524 PG 4 WC Physics, Multidisciplinary SC Physics GA 189HW UT WOS:000079899900036 ER PT J AU Yoshinari, Y Hammel, PC Cheong, SW AF Yoshinari, Y Hammel, PC Cheong, SW TI Magnetism of stripe-ordered La5/3Sr1/3NiO4 SO PHYSICAL REVIEW LETTERS LA English DT Article ID T-J MODEL; COPPER-OXIDE SUPERCONDUCTORS; SPIN CORRELATIONS; CHARGE STRIPES; DOMAIN-WALL; ANTIFERROMAGNET; LA2NIO4+DELTA; DYNAMICS; PHASE; FLUCTUATIONS AB La-139 nuclear magnetic resonance studies reveal markedly different magnetic properties of the two sites created by the charged domain wall formation in La5/3ST1/3NiO4 Nuclear magnetic resonance is slow compared to neutron scattering; we observe a 30 K suppression in magnetic ordering temperature indicating glassy behavior. Applied magnetic field reorients the in-plane ordered moments with respect to the lattice, but the relative orientation of the spins among themselves is stiff and broadly distributed. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. AT&T Bell Labs, Lucent Technol, Murray Hill, NJ 07974 USA. RP Yoshinari, Y (reprint author), Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. RI Hammel, P Chris/O-4845-2014 OI Hammel, P Chris/0000-0002-4138-4798 NR 37 TC 22 Z9 22 U1 0 U2 5 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 APR 26 PY 1999 VL 82 IS 17 BP 3536 EP 3539 DI 10.1103/PhysRevLett.82.3536 PG 4 WC Physics, Multidisciplinary SC Physics GA 189HW UT WOS:000079899900039 ER PT J AU Hughes, E Koons, JM Wang, JX Ellis, PD AF Hughes, E Koons, JM Wang, JX Ellis, PD TI Solid-state NMR investigation of promoted silver catalysts SO JOURNAL OF CATALYSIS LA English DT Article ID ETHYLENE EPOXIDATION; MAGNETIC-RESONANCE; ADSORPTION; OXYGEN; C-13; AG(110); SPECTROSCOPY; SURFACES; MODEL AB The effects of cesium promoters on silver catalysts, supported by gamma-alumina, were studied by adsorbing mono- or dilabeled [C-13]ethylene onto the catalysts and performing low-temperature (70 K) solid-state C-13 NMR measurements on the ethylene, Selective isotopic enrichment was used to investigate the electronic environment present in and around the ethylene molecule as a function of promoter concentration. Changes in the spectroscopic parameters describing the ethylene lineshapes were extracted using a nonlinear least-squares procedure. These parameters were then used to determine the structure of the ethylene molecule on the surface and to probe the changes induced by adding cesium promoters. Similarly, the state of cesium in the catalyst system was investigated by spin-echo double-resonance spectroscopy and scanning electron microscopy X-ray fluorescence methods. The results imply that the form of cesium is not that of an oxide but, in all probability, reflect those of a cation-anion pair. (C) 1999 Academic Press. C1 Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. Univ S Carolina, Dept Chem & Biochem, Columbia, SC 29208 USA. RP Ellis, PD (reprint author), Pacific NW Natl Lab, Environm Mol Sci Lab, Battelle Blvd,POB 999, Richland, WA 99352 USA. NR 38 TC 0 Z9 0 U1 2 U2 6 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 APR 25 PY 1999 VL 183 IS 2 BP 182 EP 195 DI 10.1006/jcat.1999.2412 PG 14 WC Chemistry, Physical; Engineering, Chemical SC Chemistry; Engineering GA 191XG UT WOS:000080046500003 ER PT J AU Newsom, HE Hagerty, JJ Goff, F AF Newsom, HE Hagerty, JJ Goff, F TI Mixed hydrothermal fluids and the origin of the Martian soil SO JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS LA English DT Article ID CHEMICAL-COMPOSITION; MERAPI-VOLCANO; MARS SOIL; GEOCHEMISTRY; COMPONENTS; VOLATILES; SYSTEMS; CRATER; ICE; MINERALOGY AB The Martian soil consists mainly of weathered basaltic rock and a "salt" component enriched in volatile and mobile elements, primarily sulfur, chlorine, sodium, and potassium. Since the discovery of this mobile element component by the Viking X-ray fluorescence spectrometer, volcanic aerosols have been considered a likely source for these enrichments. Alternative sources of the mobile element component are fluids supplied to the surface by hydrothermal processes related to impact craters and volcanism. We show that a mixed hydrothermal fluid model can successfully explain the composition of the mobile element component of the soil. This model is constructed using terrestrial analogs constrained by the Viking and Pathfinder measurements of the Martian soil chemistry. The potential hydrothermal fluid contributions to the soil are tightly constrained because the relative abundances of the mobile elements in hydrothermal fluids are nearly constant. The two end-member types of hydrothermal fluids considered in the model are the neutral-chloride and the acid-sulfate type. The neutral-chloride fluids have high Cl and Na contents and a significant amount of K, but their S abundance relative to Cl (S/Cl ratio) is too low to match the Martian soil. However, acid-sulfate hydrothermal systems characterized by substantial vapor transport and high S/Cl ratios are likely on Mars due to the low abundance of water. Indeed, as the availability of water declines in a hydrothermal system, the neutral-chloride system can evolve to a vapor-dominated acid-sulfate system. A combination of the two types of fluids can quantitatively explain the S and Cl abundance in the soil and provide reasonable abundances of other mobile elements, including Na, K, and Br, without predicting an excess of any element measured in the soil. However, the hydrothermal fluids are unlikely to be involved in the formation of the magnetic minerals in the soil because the Fe contents of the fluids are too low. Although the acid-sulfate fluids have Fe concentrations a factor of 100 larger than the neutral-chloride fluids, the acid-sulfate fluids would contribute less than 1% of the total Fe in the soil. The volcanic aerosol models are poorly constrained in contrast to the hydrothermal fluid models because in volcanic aerosols the relative abundances of the mobile elements are highly variable. Therefore, while volcanic aerosols can explain the mobile element component of the soil, significant contributions from other sources cannot be excluded. Determining the relative contributions of hydrothermal components compared to volcanic aerosols will require measurements in the Martian soil of trace elements that provide signatures of the hydrothermal fluids, such as high lithium contents that are associated with neutral-chloride fluids. C1 Univ New Mexico, Inst Meteorit, Albuquerque, NM 87131 USA. Univ New Mexico, Dept Earth & Planetary Sci, Albuquerque, NM 87131 USA. Univ Calif Los Alamos Natl Lab, Div Earth & Environm Sci, Los Alamos, NM 87545 USA. RP Newsom, HE (reprint author), Univ New Mexico, Inst Meteorit, Northrup Hall, Albuquerque, NM 87131 USA. NR 76 TC 73 Z9 73 U1 4 U2 10 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0148-0227 J9 J GEOPHYS RES-PLANET JI J. Geophys. Res.-Planets PD APR 25 PY 1999 VL 104 IS E4 BP 8717 EP 8728 DI 10.1029/1998JE900043 PG 12 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA 188FV UT WOS:000079836900017 ER PT J AU Zhu, YT Valdez, JA Beyerlein, IJ Zhou, SJ Liu, C Stout, MG Butt, DP Lowe, TC AF Zhu, YT Valdez, JA Beyerlein, IJ Zhou, SJ Liu, C Stout, MG Butt, DP Lowe, TC TI Mechanical properties of bone-shaped-short-fiber reinforced composites SO ACTA MATERIALIA LA English DT Article DE bone-shaped short fibers; composites; mechanical properties, fracture & fracture toughness; theory and modeling ID METAL-MATRIX COMPOSITES; PULL-OUT; INTERFACE; STRESSES; STRENGTH AB Short-fiber composites usually have low strength and toughness relative to continuous fiber composites, an intrinsic problem caused by discontinuities at fiber ends and interfacial debonding. In this work a model polyethylene bone-shaped-short (BSS) fiber-reinforced polyester-matrix composite was fabricated to prove that fiber morphology, instead of interfacial strength, solves this problem. Experimental tensile and fracture toughness lest results show that BSS fibers can bridge matrix cracks more effectively, and consume many times more energy when pulled out, than conventional straight short (CSS) fibers. This leads to both higher strength and fracture toughness for the BSS-fiber composites. A computational model was developed to simulate crack propagation in both BSS- and CSS-fiber composites, accounting for stress concentrations, interface debonding, and fiber pull-out. Model predictions were validated by experimental results and will be useful in optimizing BSS-fiber morphology and other material system parameters. (C) 1999 Acta Metallurgica Inc. Published by Elsevier Science Lid. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. Univ Calif Los Alamos Natl Lab, Div Appl Phys, Los Alamos, NM 87545 USA. RP Lowe, TC (reprint author), Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, MS G755, Los Alamos, NM 87545 USA. RI Zhu, Yuntian/B-3021-2008; Butt, Darryl/B-7480-2008; Beyerlein, Irene/A-4676-2011 OI Zhu, Yuntian/0000-0002-5961-7422; Butt, Darryl/0000-0003-4501-8864; NR 30 TC 31 Z9 36 U1 0 U2 8 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1359-6454 J9 ACTA MATER JI Acta Mater. PD APR 23 PY 1999 VL 47 IS 6 BP 1767 EP 1781 DI 10.1016/S1359-6454(99)00071-3 PG 15 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA 195TU UT WOS:000080268900007 ER PT J AU Christon, MA AF Christon, MA TI The influence of the mass matrix on the dispersive nature of the semi-discrete, second-order wave equation SO COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING LA English DT Article ID FINITE-ELEMENT METHOD; FOURIER-ANALYSIS; BOUNDARY-CONDITIONS; DIFFERENCE-SCHEMES; GROUP-VELOCITY; GALERKIN; PROPAGATION AB The application of discrete solution methods to the second-order wave equation can yield a dispersive representation of the non-dispersive wave propagation problem resulting in a phase speed that depends, not only upon the wavelength of the signal being propagated, but also upon the direction of propagation. In this work, the dependence of the dispersive errors on the wave propagation direction, mesh aspect ratio and wave number is investigated with the goal of understanding and hopefully reducing the phase and group errors associated with the two-dimensional bilinear finite element. An analysis of the dispersive effects associated with the consistent, row-sum lumped and higher-order mass matrices has led to a reduced-coupling 'penta-diagonal' mass matrix that yields improved phase and group errors with respect to wavelength and propagation direction. The influence of row-sum lumping the finite element mass matrix is demonstrated to always introduce lagging phase and group error, while a linear combination of the lumped and consistent mass matrices, i.e. a higher-order mass matrix, is shown to improve the dispersion characteristics of both the reduced and full-integration element. Using a 2.5% phase error metric, the higher-order mass matrix can reduce the mesh resolution requirements relative to the lumped mass matrix by nearly a factor of two in one dimension; a factor of 4 in two dimensions. Similarly, the reduced-coupling mass matrix can reduce the grid requirements by a factor of approximately four relative to the lumped mass matrix; a factor of 16 in two dimensions. Although the reduced-coupling mass matrix requires additional storage relative to the lumped mass, the factor of 16 reduction in grid requirements promises tremendous overall savings for computing a fixed wavelength spectrum, or alternatively for resolving shorter wavelengths with a fixed grid resolution. (C) 1999 Elsevier Science S.A. All rights reserved. C1 Sandia Natl Labs, Computat Phys R&D Dept, Albuquerque, NM 87185 USA. RP Christon, MA (reprint author), Sandia Natl Labs, Computat Phys R&D Dept, POB 5800,M-S 0819, Albuquerque, NM 87185 USA. NR 25 TC 35 Z9 36 U1 0 U2 0 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0045-7825 J9 COMPUT METHOD APPL M JI Comput. Meth. Appl. Mech. Eng. PD APR 23 PY 1999 VL 173 IS 1-2 BP 147 EP 166 DI 10.1016/S0045-7825(98)00266-7 PG 20 WC Engineering, Multidisciplinary; Mathematics, Interdisciplinary Applications; Mechanics SC Engineering; Mathematics; Mechanics GA 194TW UT WOS:000080210500010 ER PT J AU Anderson, PM Walsh, MA Perrakis, A Wronski, J Joachimiak, A AF Anderson, PM Walsh, MA Perrakis, A Wronski, J Joachimiak, A TI The structure of decameric cyanase involves a novel arrangement of subunits integral to five active sites SO FASEB JOURNAL LA English DT Meeting Abstract C1 Univ Minnesota, Duluth, MN 55812 USA. Argonne Natl Lab, Argonne, IL 60439 USA. European Mol Biol Lab, F-38042 Grenoble, France. NR 0 TC 0 Z9 0 U1 0 U2 0 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD APR 23 PY 1999 VL 13 IS 7 SU S BP A1364 EP A1364 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 226QX UT WOS:000082033400248 ER PT J AU Campisi, J AF Campisi, J TI A cellular bash for aging and cancer SO FASEB JOURNAL LA English DT Meeting Abstract C1 Lawrence Berkeley Lab, Dept Cell & Mol Biol, Div Life Sci, Berkeley, CA 94720 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD APR 23 PY 1999 VL 13 IS 7 SU S BP A1327 EP A1327 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 226QX UT WOS:000082033400044 ER PT J AU Edwards, JV Batiste, SL Gibbins, BM Goheen, SC AF Edwards, JV Batiste, SL Gibbins, BM Goheen, SC TI Affinity of cotton-bound peptides for the serine protease elastase SO FASEB JOURNAL LA English DT Meeting Abstract C1 USDA ARS, So Reg Res Ctr, Text Chem Res Unit, New Orleans, LA 70124 USA. Pacific NW Lab, Richland, WA 99352 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD APR 23 PY 1999 VL 13 IS 7 SU S BP A1495 EP A1495 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 226QX UT WOS:000082033400999 ER PT J AU Goheen, SC Herbold, CW Miller, JH Marx, JG Springer, DL AF Goheen, SC Herbold, CW Miller, JH Marx, JG Springer, DL TI Surface-mediated unfolding of cytochrome c SO FASEB JOURNAL LA English DT Meeting Abstract C1 Pacific NW Lab, Richland, WA 99352 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD APR 23 PY 1999 VL 13 IS 7 SU S BP A1495 EP A1495 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 226QX UT WOS:000082033400997 ER PT J AU Gonzalez, RL Tinoco, I AF Gonzalez, RL Tinoco, I TI Solution structure and thermodynamics of a divalent metal ion binding site in an RNA pseudoknot SO FASEB JOURNAL LA English DT Meeting Abstract C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Lawrence Berkeley Lab, Dept Biol Struct, Phys Biosci Div, Berkeley, CA 94720 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD APR 23 PY 1999 VL 13 IS 7 SU S BP A1326 EP A1326 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 226QX UT WOS:000082033400037 ER PT J AU Hilsenbeck, JL Gibbins, BM Goheen, SC AF Hilsenbeck, JL Gibbins, BM Goheen, SC TI The behavior and chromatography of fibrinogen SO FASEB JOURNAL LA English DT Meeting Abstract C1 Washington State Univ, Pullman, WA 99164 USA. Pacific NW Natl Lab, Richland, WA 99352 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD APR 23 PY 1999 VL 13 IS 7 SU S BP A1555 EP A1555 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 226QX UT WOS:000082033401340 ER PT J AU Lee, T Karasawa, K Inoue, K Aria, H Aoki, J AF Lee, T Karasawa, K Inoue, K Aria, H Aoki, J TI Some of the recombinant platelet-activating factor (PAF) acetylhydrolases (AH) possess transacetylase activities SO FASEB JOURNAL LA English DT Meeting Abstract C1 Oak Ridge Associated Univ, Oak Ridge, TN USA. Univ Tokyo, Tokyo, Japan. NR 0 TC 1 Z9 1 U1 0 U2 0 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD APR 23 PY 1999 VL 13 IS 7 SU S BP A1380 EP A1380 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 226QX UT WOS:000082033400346 ER PT J AU Li, J Derewenda, U Dauter, Z Smith, S Derewenda, Z AF Li, J Derewenda, U Dauter, Z Smith, S Derewenda, Z TI X-ray crystal structure of E.coli thioesterase by MAD phasing SO FASEB JOURNAL LA English DT Meeting Abstract C1 Univ Virginia, Brookhaven Natl Lab, Childrens Hosp Oakland, Charlottesville, VA 22903 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD APR 23 PY 1999 VL 13 IS 7 SU S BP A1556 EP A1556 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 226QX UT WOS:000082033401347 ER PT J AU Liburdy, RP Kanitz, H Afzal, J Harland, J Savage, R AF Liburdy, RP Kanitz, H Afzal, J Harland, J Savage, R TI Differential protein expression in human breast cancer cells treated with tamoxifen and environmental magnetic fields SO FASEB JOURNAL LA English DT Meeting Abstract C1 Lawrence Berkeley Lab, Berkeley, CA 94720 USA. NIOSH, Cincinnati, OH 45226 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD APR 23 PY 1999 VL 13 IS 7 SU S BP A1538 EP A1538 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 226QX UT WOS:000082033401244 ER PT J AU Phaire-Washington, L AF Phaire-Washington, L TI Overcoming obstacles in academia: Tenure - Obstacle or opportunity. SO FASEB JOURNAL LA English DT Meeting Abstract C1 Argonne Natl Lab, Argonne, IL 60439 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD APR 23 PY 1999 VL 13 IS 7 SU S BP A1432 EP A1432 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 226QX UT WOS:000082033400633 ER PT J AU Schmitz, M Tinoco, I AF Schmitz, M Tinoco, I TI NMR solution studies on the P4 element of bacterial RNAse P RNA SO FASEB JOURNAL LA English DT Meeting Abstract C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Lawrence Berkeley Lab, Struct Biol Div, Berkeley, CA USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD APR 23 PY 1999 VL 13 IS 7 SU S BP A1323 EP A1323 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 226QX UT WOS:000082033400025 ER PT J AU Sen, CK Roy, S Packer, L AF Sen, CK Roy, S Packer, L TI Potentiation of Fas mediated apoptosis by redox-active lipoic acid SO FASEB JOURNAL LA English DT Meeting Abstract C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RI Sen, Chandan/A-8762-2013 NR 0 TC 0 Z9 0 U1 0 U2 0 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD APR 23 PY 1999 VL 13 IS 7 SU S BP A1343 EP A1343 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 226QX UT WOS:000082033400131 ER PT J AU Williams, KE Baldwin, MA Turteltaub, KW Burlingame, AL AF Williams, KE Baldwin, MA Turteltaub, KW Burlingame, AL TI Bone marrow protein targets of benzene in mice SO FASEB JOURNAL LA English DT Meeting Abstract C1 Univ Calif San Francisco, San Francisco, CA 94143 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD APR 23 PY 1999 VL 13 IS 7 SU S BP A1408 EP A1408 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 226QX UT WOS:000082033400505 ER PT J AU Yaswen, P Garbe, J Wigington, D Nijjar, T Levine, G Stampfer, MR AF Yaswen, P Garbe, J Wigington, D Nijjar, T Levine, G Stampfer, MR TI Immortalization of human mammary epithelial cells (HMEC): A non-viral perspective. SO FASEB JOURNAL LA English DT Meeting Abstract C1 Lawrence Berkeley Lab, Berkeley, CA 94720 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD APR 23 PY 1999 VL 13 IS 7 SU S BP A1329 EP A1329 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 226QX UT WOS:000082033400054 ER PT J AU Zheng, MX Wu, M Silverman, S Cech, T Tinoco, I AF Zheng, MX Wu, M Silverman, S Cech, T Tinoco, I TI RNA folding and mutation studies of the P5abc subdomain from the tetrahymena group I intron ribozyme SO FASEB JOURNAL LA English DT Meeting Abstract C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Lawrence Berkeley Lab, Dept Biol Struct, Phys Biosci Div, Berkeley, CA 94720 USA. Univ Colorado, Dept Chem & Biochem, Boulder, CO 80309 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD APR 23 PY 1999 VL 13 IS 7 SU S BP A1325 EP A1325 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 226QX UT WOS:000082033400034 ER PT J AU Kim, SY Hwang, KY Kim, SH Sung, HC Han, YS Cho, YJ AF Kim, SY Hwang, KY Kim, SH Sung, HC Han, YS Cho, YJ TI Structural basis for cold adaptation - Sequence, biochemical properties, and crystal structure of malate dehydrogenase from a psychrophile Aquaspirillium arcticum SO JOURNAL OF BIOLOGICAL CHEMISTRY LA English DT Article ID ACTIVE CITRATE SYNTHASE; ESCHERICHIA-COLI; LACTATE-DEHYDROGENASE; ANTARCTIC BACTERIUM; RESOLUTION; ENZYMES; THERMOSTABILITY; PURIFICATION; EXPRESSION; STABILITY AB Aquaspillium arcticum is a psychrophilic bacterium that was isolated from arctic sediment and grows optimally at 4 degrees C, We have cloned, purified, and characterized malate dehydrogenase from A. arcticum (Aa MDH). We also have determined the crystal structures of apo-Aa MDH, Aa MDH.NADH binary complex, and Aa MDH.NAD.oxaloacetate ternary complex at 1.9-, 2.1-, and 2.5-Angstrom resolutions, respectively. The Aa MDH sequence is most closely related to the sequence of a thermophilic MDH from Thermus flavus (Tf MDH), showing 61% sequence identity and over 90% sequence similarity. Stability studies show that Aa MDH has a half-life of 10 min at 55 degrees C, whereas Tf MDH is fully active at 90 degrees C for 1 h. Aa MDH shows 2-3-fold higher catalytic efficiency compared with a mesophilic or a thermophilic MDH at the temperature range 4-10 degrees C. Structural comparison of Aa MDH and Tf MDH suggests that the increased relative flexibility of active site residues, favorable surface charge distribution for substrate and cofactor, and the reduced intersubunit ion pair interactions may be the major factors for the efficient catalytic activity of Aa MDH at low temperatures. C1 Korea Inst Sci & Technol, Struct Biol Ctr, Seoul 130650, South Korea. Korea Univ, Dept Biotechnol, Seoul, South Korea. Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Cho, YJ (reprint author), Korea Inst Sci & Technol, Struct Biol Ctr, POB 131, Seoul 130650, South Korea. NR 33 TC 120 Z9 129 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 APR 23 PY 1999 VL 274 IS 17 BP 11761 EP 11767 DI 10.1074/jbc.274.17.11761 PG 7 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 188EX UT WOS:000079834800048 PM 10206992 ER PT J AU Francis, CW Timpson, ME Wilson, JH AF Francis, CW Timpson, ME Wilson, JH TI Bench- and pilot-scale studies relating to the removal of uranium from uranium-contaminated soils using carbonate and citrate lixiviants SO JOURNAL OF HAZARDOUS MATERIALS LA English DT Article DE uranium removal; carbonate lixiviant; citrate lixiviant AB Development of the nuclear industry has resulted in soil becoming contaminated with uranium from a variety of sources. To avoid the disposal of these soils in conventional low-level radwaste burial sites, a technology is needed to extract/leach and concentrate uranium in soil into small volumes of an acceptable waste form and returning the soil to its original place. Two lixiviants, carbonate and citrate, were evaluated as to their ability to extract uranium from soil in a soil washing engineering process. The objective was to use a washing/extracting process to selectively remove the uranium from soil without seriously degrading the soil's physicochemical characteristics or generating a secondary waste form that is difficult to manage and/or dispose. Both carbonate and citric acid lixiviants were observed to be effective extractants to remove uranium from the soils tested. Carbonate, because of the its ability to be recycled and its tendency to be more selective for uranium, is preferred for most soils. A major obstacle for using citric acid as well as mineral-based acids is their generation of waste streams from which it is difficult to remove uranium and manage (and dispose of any residual waste water sludges) in an environmentally acceptable manner. The removal of uranium was examined for three soils sampled from two US Department of Energy sites. Two soils were from the facility formerly called the Feed Materials Production Center at Fernald, Ohio and the other soil was from the Oak Ridge Tennessee Y-12 Plant. In the bench-scale studies, general relationships, such as the effect of carbonate and citrate concentrations, pH, the presence of oxidants, such as KMnO4, temperature, and extraction time were investigated. The best pilot-scale treatment consisted of three successive extractions with 0.25 M carbonate-bicarbonate (in presence of KMnO4 as an oxidant) at 40 degrees C followed with two water rinses. (C) 1999 Published by Elsevier Science B.V. All rights reserved. C1 Oak Ridge Natl Lab, Div Environm Sci, Div Chem Technol, Oak Ridge, TN 37831 USA. Oak Ridge Associated Univ, Oak Ridge, TN USA. RP Francis, CW (reprint author), Oak Ridge Natl Lab, Div Environm Sci, Div Chem Technol, POB 2008,MS-6038, Oak Ridge, TN 37831 USA. NR 10 TC 28 Z9 28 U1 1 U2 7 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 APR 23 PY 1999 VL 66 IS 1-2 BP 67 EP 87 DI 10.1016/S0304-3894(98)00209-X PG 21 WC Engineering, Environmental; Engineering, Civil; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 202QJ UT WOS:000080663400006 PM 10379031 ER PT J AU Negri, MC Swift, NA Carfagno, D Neff, RA North, J AF Negri, MC Swift, NA Carfagno, D Neff, RA North, J TI Selective removal of plutonium 238 from a canal sediment using a carbonate-chelant soil washing technology (ACT*DE*CONSM) SO JOURNAL OF HAZARDOUS MATERIALS LA English DT Article DE plutonium 238; canal sediment; ACT*DE*CONSM AB The Mound laboratory site in Miamisburg, OH, a former plutonium processing facility, contains approximately 40000 yd(3) (30,580 m(3)) of plutonium- and thorium-contaminated soils and sediments at levels that require remediation. Existing applicable remediation technologies are unsatisfactory, because they are expensive and do not provide volume reduction. ACT*DE*CONSM is a chemical soil leaching technology for the treatment of soils that utilizes contaminant dissolution via dilute selective solutions to remove radionuclides. In bench-scale tests, process parameters were developed for the optimal treatment of the Miami Erie Canal soil at the Mound site, combining the maximum plutonium removal with an acceptable amount of soil dissolution and minimizing the costs of reagents. Parameters evaluated included soil to extractant mass ratio, temperature, rinse solution composition, kinetics, and the application of several dewatering aids. Plutonium removal rates of > 95% were achieved, and the residual plutonium in the treated soil proved to be very immobile-confirming that the process had removed the most accessible species of the radionuclide. Currently being tested at Mound is an engineering scale-up that includes an attrition scrubber, a counter-current extractor, and a reverse osmosis system. Economic evaluations based on bench-scale results put the treatment cost at US$278/yd(3) (US$364/m(3)), compared to US$350/yd(3) (US$458/m(3)) for the 'box-and-bury' baseline alternative treatment system. (C) 1999 Published by Elsevier Science B.V. C1 Argonne Natl Lab, Argonne, IL 60439 USA. Selentec, Atlanta, GA 30350 USA. Mound Plant, Miamisburg, OH 45343 USA. Clemson Tech Ctr, RUST Remedial Serv, Anderson, SC 29625 USA. RP Negri, MC (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 14 TC 0 Z9 0 U1 1 U2 6 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 APR 23 PY 1999 VL 66 IS 1-2 BP 99 EP 118 DI 10.1016/S0304-3894(98)00208-8 PG 20 WC Engineering, Environmental; Engineering, Civil; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 202QJ UT WOS:000080663400008 PM 10379033 ER PT J AU Peters, RW AF Peters, RW TI Chelant extraction of heavy metals from contaminated soils SO JOURNAL OF HAZARDOUS MATERIALS LA English DT Article DE chelant extraction; soil washing; soil flushing; heavy metals; copper; lead; zinc; EDTA ID ADSORPTION-DESORPTION CHARACTERISTICS; PB-POLLUTED SOILS; CHELATING EXTRACTION; N-(2-ACETAMIDO)IMINODIACETIC ACID; PYRIDINE-2,6-DICARBOXYLIC ACID; LEAD; REMEDIATION; REMOVAL; EDTA; COPPER AB The current state of the art regarding the use of chelating agents to extract heavy metal contaminants has been addressed. Results are presented for treatability studies conducted as worst-case and representative soils from Aberdeen Proving Ground's J-Field for extraction of copper (Cu), lead (Pb), and zinc (Zn). The particle size distribution characteristics of the soils determined from hydrometer tests are approximately 60% sand, 30% silt, and 10% clay. Sequential extractions were performed on the 'as-received' soils (worst case and representative) to determine the speciation of the metal forms. The technique speciates the heavy metal distribution into an easily extractable (exchangeable) form, carbonates, reducible oxides, organically-bound, and residual forms. The results indicated that most of the metals are in forms that are amenable to soil washing (i.e. exchangeable + carbonate + reducible oxides). The metals Cu, Pb, Zn, and Cr have greater than 70% of their distribution in forms amenable to soil washing techniques, while Cd, Mn, and Fe are somewhat less amenable to soil washing using chelant extraction. However, he concentrations of Cd and Mn are low in the contaminated soil. From the batch chelant extraction studies, ethylenediaminetetraacetic acid (EDTA), citric acid, and nitrilotriacetic acid (NTA) were all effective in removing copper, lead, and zinc from the J-Field soils. Due to NTA being a Class II carcinogen, it is not recommended for use in remediating contaminated soils. EDTA and citric acid appear to offer the greatest potential as chelating agents to use in soil washing the Aberdeen Proving Ground soils. The other chelating agents studied (gluconate, oxalate, Citranox, ammonium acetate, and phosphoric acid, along with pH-adjusted water) were generally ineffective in mobilizing the heavy metals from the soils. The chelant solution removes the heavy metals (Cd, Cu, Pb, Zn, Fe, Cr, As, and Hg) simultaneously. Using a multiple-stage batch extraction, the soil was successfully treated passing both the Toxicity Characteristics Leaching Procedure (TCLP) and EPA Total Extractable Metal Limit. The final residual Pb concentration was about 300 mg/kg, with a corresponding TCLP of 1.5 mg/l. Removal of the exchangeable and carbonate fractions for Cu and Zn was achieved during the first extraction stage, whereas it required two extraction stages for the same fractions for Pb. Removal of Pb, Cu, and Zn present as exchangeable, carbonates, and reducible oxides occurred between the fourth- and fifth-stage extractions. The overall removal of copper, lead, and zinc from the multiple-stage washing were 98.9%, 98.9%, and 97.2%, respectively. The concentration and operating conditions for the soil washing extractions were not necessarily optimized. If the conditions had been optimized and using a more representative Pb concentration (similar to 12000 mg/kg), it is likely that the TCLP and residual heavy metal soil concentrations could be achieved within two to three extractions. The results indicate that the J-Field contaminated soils can be successfully treated using a soil washing technique. (C) 1999 Published by Elsevier Science B.V. All rights reserved. C1 Argonne Natl Lab, Div Energy Syst, Argonne, IL 60439 USA. RP Peters, RW (reprint author), Argonne Natl Lab, Div Energy Syst, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 90 TC 320 Z9 368 U1 31 U2 210 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 APR 23 PY 1999 VL 66 IS 1-2 BP 151 EP 210 DI 10.1016/S0304-3894(99)00010-2 PG 60 WC Engineering, Environmental; Engineering, Civil; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA 202QJ UT WOS:000080663400011 PM 10379036 ER PT J AU de Heinzelin, J Clark, JD White, T Hart, W Renne, P WoldeGabriel, G Beyene, Y Vrba, E AF de Heinzelin, J Clark, JD White, T Hart, W Renne, P WoldeGabriel, G Beyene, Y Vrba, E TI Environment and behavior of 2.5-million-year-old Bouri hominids SO SCIENCE LA English DT Article ID MIDDLE-AWASH VALLEY; OLDUVAI GORGE; LONG BONES; ETHIOPIA; PERCUSSION; TANZANIA; AGES AB The Hata Member of the Bouri Formation is defined for Pliocene sedimentary outcrops in the Middle; Awash Valley, Ethiopia. The Hata Member is dated to 2.5 million years ago and has produced a new species of Australopithecus and hominid postcranial remains not currently assigned to species. Spatially associated zooarchaeological remains show that hominids acquired meat and marrow by 2.5 million years ago and that they are the near contemporary of Oldowan artifacts at nearby Cona. The combined evidence suggests that behavioral changes associated with Lithic technology and enhanced carnivory may have been coincident with the emergence of the Homo clade from Australopithecus afarensis in eastern Africa. C1 Univ Calif Berkeley, Museum Vertebrate Zool, Lab Human Evolutionary Studies, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Integrat Biol, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Geol & Geophys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Anthropol, Berkeley, CA 94720 USA. Inst Royal Sci Nat Belgique, B-1000 Brussels, Belgium. Miami Univ, Dept Geol, Oxford, OH 45056 USA. Berkeley Geochronol Ctr, Berkeley, CA 94709 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Minist Informat & Culture, Dept Anthropol & Archaeol, Addis Ababa, Ethiopia. Yale Univ, Dept Geol & Geophys, New Haven, CT 06511 USA. RP White, T (reprint author), Univ Calif Berkeley, Museum Vertebrate Zool, Lab Human Evolutionary Studies, Berkeley, CA 94720 USA. RI Davidson, Iain/A-9216-2011 NR 18 TC 204 Z9 210 U1 2 U2 42 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 USA SN 0036-8075 J9 SCIENCE JI Science PD APR 23 PY 1999 VL 284 IS 5414 BP 625 EP 629 PG 5 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 190FH UT WOS:000079951100040 PM 10213682 ER PT J AU Lehr, L Zanni, MT Frischkorn, C Weinkauf, R Neumark, DM AF Lehr, L Zanni, MT Frischkorn, C Weinkauf, R Neumark, DM TI Electron solvation in finite systems: Femtosecond dynamics of iodide center dot(water)(n) anion clusters SO SCIENCE LA English DT Article ID PHOTOELECTRON-SPECTROSCOPY; WATER CLUSTERS; MOLECULAR-DYNAMICS; HYDRATED ELECTRON; AQUEOUS CHLORIDE; PHOTODETACHMENT; PHOTODISSOCIATION; STATES; IONS AB Electron solvation dynamics in photoexcited anion clusters of l(-)(D2O)(n=4-6) and I-(H2O)(4-6) were probed by using femtosecond photoelectron spectroscopy (FPES). An ultrafast pump pulse excited the anion to the cluster analog of the charge-transfer-to-solvent state seen for I- in aqueous solution. Evolution of this state was monitored by time-resolved photoelectron spectroscopy using an ultrafast probe pulse. The excited n = 4 clusters showed simple population decay, but in the n = 5 and 6 clusters the solvent molecules rearranged to stabilize and localize the excess electron, showing characteristics associated with electron solvation dynamics in bulk water. Comparison of the FPES of I-(D2O)(n) with I-(H2O)(n) indicates more rapid solvation in the H2O clusters. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA. RP Neumark, DM (reprint author), Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. RI Zanni, Martin/K-2707-2013; Neumark, Daniel/B-9551-2009 OI Neumark, Daniel/0000-0002-3762-9473 NR 26 TC 196 Z9 198 U1 1 U2 30 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 APR 23 PY 1999 VL 284 IS 5414 BP 635 EP 638 DI 10.1126/science.284.5414.635 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 190FH UT WOS:000079951100042 ER PT J AU Wu, RL Odom, JD Dunlap, RB Silks, LA AF Wu, RL Odom, JD Dunlap, RB Silks, LA TI Reaction of alcohols (via the Mitsunobu-reaction) and alkyl halides with chiral selone derivatizing agents SO TETRAHEDRON-ASYMMETRY LA English DT Article ID SE-77 NMR-SPECTROSCOPY; ENANTIOMERIC EXCESS DETERMINATION; MAGNETIC-RESONANCE SPECTROSCOPY; OXAZOLIDINE-2-SELONES; PURITY AB Coupling of a selone chiral derivatizing agent (CDA) to D,L-alkyl halides gives Se-alkylated adducts in yields ranging from 76-97%. Reaction of D,L-alcohols with the selone CDAs via the Mitsunobu reaction has given rise to Se-alkylated adducts in yields ranging from 82-92%. Examination of the Se-77 NMR spectra of the resulting diastereomeric adducts indicates that discrimination of remotely disposed chiral centers is possible using this technique. (C) 1999 Elsevier Science Ltd. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Biosci & Biotechnol Grp, Los Alamos, NM 87545 USA. Univ S Carolina, Dept Chem & Biochem, Columbia, SC 29208 USA. RP Silks, LA (reprint author), Univ Calif Los Alamos Natl Lab, Biosci & Biotechnol Grp, CST-4 MS,E-529, Los Alamos, NM 87545 USA. NR 16 TC 17 Z9 17 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0957-4166 J9 TETRAHEDRON-ASYMMETR JI Tetrahedron: Asymmetry PD APR 23 PY 1999 VL 10 IS 8 BP 1465 EP 1470 DI 10.1016/S0957-4166(99)00140-8 PG 6 WC Chemistry, Inorganic & Nuclear; Chemistry, Organic; Chemistry, Physical SC Chemistry GA 204FH UT WOS:000080753100009 ER PT J AU Taylor, TR Asmis, KR Zanni, MT Neumark, DM AF Taylor, TR Asmis, KR Zanni, MT Neumark, DM TI Characterization of the I-3 radical by anion photoelectron spectroscopy SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID AB-INITIO CALCULATIONS; ELECTRONIC STATES; TRIHALIDE ANIONS; CLUSTERS; IODINE; ION; CL; STABILITY; SPECTRA; CATIONS AB The ground and first excited states of the I-3 radical are characterized by photoelectron spectroscopy of I-3(-) and Ar . I-3(-) at 266 nm. The electron affinity of I-3 is 4.226+/-0.013 eV. Based on the recently determined bond dissociation energy of I-3(-), the I-3 ground state is bound by 0.143+/-0.06 eV. The first excited state of I-3 lies 0.27 eV above the ground state. A vibrational progression is seen in the ground state band of the I-3(-) photoelectron spectrum. The addition of an argon atom to I-3(-) reduces the contribution of hot bands to the photoelectron spectrum, facilitating the interpretation of the vibrational structure. Simulations indicate that the I-3 ground state is linear with a symmetric stretch frequency of 115+/-5 cm(-1) and is likely to be centrosymmetric. (C) 1999 American Institute of Physics. [S0021-9606(99)02016-4]. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA. RP Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. RI Zanni, Martin/K-2707-2013; Asmis, Knut/N-5408-2014; Neumark, Daniel/B-9551-2009 OI Asmis, Knut/0000-0001-6297-5856; Neumark, Daniel/0000-0002-3762-9473 NR 30 TC 22 Z9 23 U1 1 U2 5 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 APR 22 PY 1999 VL 110 IS 16 BP 7607 EP 7609 DI 10.1063/1.478672 PG 3 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 186QC UT WOS:000079739600001 ER PT J AU Baboul, AG Curtiss, LA Redfern, PC Raghavachari, K AF Baboul, AG Curtiss, LA Redfern, PC Raghavachari, K TI Gaussian-3 theory using density functional geometries and zero-point energies SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID QUADRATIC CONFIGURATION-INTERACTION; MOLLER-PLESSET; COMPUTATION; AFFINITIES; EXCHANGE; CH4+ AB A variation of Gaussian-3 (G3) theory is presented in which the geometries and zero-point energies are obtained from B3LYP density functional theory [B3LYP/6-31G(d)] instead of geometries from second-order perturbation theory [MP2(FU)/6-31G(d)] and zero-point energies from Hartree-Fock theory [HF/6-31G(d)]. This variation, referred to as G3//B3LYP, is assessed on 299 energies (enthalpies of formation, ionization potentials, electron affinities, proton affinities) from the G2/97 test set [J. Chem. Phys. 109, 42 (1998)]. The G3//B3LYP average absolute deviation from experiment for the 299 energies is 0.99 kcal/mol compared to 1.01 kcal/mol for G3 theory. Generally, the results from the two methods are similar, with some exceptions. G3//B3LYP theory gives significantly improved results for several cases for which MP2 theory is deficient for optimized geometries, such as CN and O-2(+). However, G3//B3LYP does poorly for ionization potentials that involve a Jahn-Teller distortion in the cation (CH4+, BF3+, BCl3+) because of the B3LYP/6-31G(d) geometries. The G3(MP2) method is also modified to use B3LYP/6-31G(d) geometries and zero-point energies. This variation, referred to as G3(MP2)//B3LYP, has an average absolute deviation of 1.25 kcal/mol compared to 1.30 kcal/mol for G3(MP2) theory. Thus, use of density functional geometries and zero-point energies in G3 and G3(MP2) theories is a useful alternative to MP2 geometries and HF zero-point energies. (C) 1999 American Institute of Physics. [S0021-9606(99)30512-2]. C1 Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. AT&T Bell Labs, Lucent Technol, Murray Hill, NJ 07974 USA. RP Baboul, AG (reprint author), Argonne Natl Lab, Div Chem, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 28 TC 1282 Z9 1294 U1 8 U2 58 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD APR 22 PY 1999 VL 110 IS 16 BP 7650 EP 7657 DI 10.1063/1.478676 PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 186QC UT WOS:000079739600006 ER PT J AU Wilson, AK Woon, DE Peterson, KA Dunning, TH AF Wilson, AK Woon, DE Peterson, KA Dunning, TH TI Gaussian basis sets for use in correlated molecular calculations. IX. The atoms gallium through krypton SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID ELECTRON CORRELATION-ENERGY; EQUILIBRIUM POTENTIAL-ENERGY; BODY PERTURBATION-THEORY; DIPOLE-MOMENT FUNCTIONS; COUPLED-CLUSTER SINGLE; CONSISTENT BASIS-SETS; WAVE-FUNCTIONS; BENCHMARK CALCULATIONS; CONFIGURATION-INTERACTION; SYSTEMATIC SEQUENCES AB Valence correlation consistent and augmented correlation consistent basis sets have been determined for the third row, main group atoms gallium through krypton. The methodology, originally developed for the first row atoms, was first applied to the selenium atom, resulting in the expected natural groupings of correlation functions (although higher angular momentum functions tend to be relatively more important for the third row atoms as they were for the second row atoms). After testing the generality of the conclusions for the gallium atom, the procedure was used to generate correlation consistent basis sets for all of the atoms gallium through krypton. The correlation consistent basis sets for the third row main group atoms are as follows: cc-pVDZ: (14s11p6d)/[5s4p2d]; cc-pVTZ: (20s13p9d1f)/[6s5p3d1f]; cc-pVQZ: (21s16p12d2f1g)/[7s6p4d2f1g]; cc-pV5Z: (26s17p13d3f2g1h)/[8s7p5d3f 2g1h]. Augmented sets were obtained by adding diffuse functions to the above sets (one for each angular momentum present in the set), with the exponents of the additional functions optimized in calculations on the atomic anions. Test calculations on the atoms as well as selected molecules with the new basis sets show good convergence to an apparent complete basis set limit. (C) 1999 American Institute of Physics. [S0021-9606(99)30515-8]. C1 Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. Washington State Univ, Dept Chem, Richland, WA 99352 USA. RP Wilson, AK (reprint author), Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. EM angela.wilson@pnl.gov; woon@hecla.molres.org; kirk.peterson@pnl.gov; thom.dunning@pnl.gov NR 63 TC 824 Z9 825 U1 2 U2 46 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD APR 22 PY 1999 VL 110 IS 16 BP 7667 EP 7676 DI 10.1063/1.478678 PG 10 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 186QC UT WOS:000079739600008 ER PT J AU He, G Seth, M Tokue, I Macdonald, RG AF He, G Seth, M Tokue, I Macdonald, RG TI Experimental and theoretical determination of the magnetic dipole transition moment for the Br(4p(5))(P-2(1/2)<- P-2(3/2)) fine-structure transition and the quantum yield of Br(P-2(1/2)) from the 193 nm photolysis of BrCN SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID ABSORPTION-SPECTROSCOPY; HYPERFINE-STRUCTURE; RATE-CONSTANT; LASER GAIN; HCN; PHOTODISSOCIATION; DYNAMICS; ICN; STATES; ATOM AB The integrated-absorption coefficients of several hyperfine lines of the magnetic dipole allowed transition of the bromine atom, Br, center at 3685.2 cm(-1) were measured, and a value for the square of the magnetic dipole transition moment of the Br atom was determined. A theoretical calculation for the magnetic dipole transition moment was also carried out using a relativistic ab initio atomic structure formulation. The theoretical value was in excellent agreement with the value predicted assuming pure LS coupling, and in reasonable agreement with experiment. The Br atom was generated in equal concentration with the cyano radical (CN) by the 193 nm photolysis of cyanogen bromine, BrCN. The CN radicals were titrated by the rapid reaction with C3H8 to generate HCN and a small amount of HNC. Both time-resolved and frequency-scanned infrared absorption spectroscopy were used to monitor the Br, HCN, and HNC species. The photolysis of BrCN at 193 nm produced both the ground state Br(P-2(3/2)) and the spin-orbit excited Br(P-2(1/2)) atoms, and the yield for the production of Br(P-2(1/2)) atoms was measured to be 0.31+/-0.01. The rate constants for the quenching of Br(P-2(1/2)) by BrCN and C3H8 at 293 K were also determined. [S0021-9606(99)01416-6]. C1 Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. RP He, G (reprint author), Argonne Natl Lab, Div Chem, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 52 TC 3 Z9 3 U1 0 U2 7 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD APR 22 PY 1999 VL 110 IS 16 BP 7821 EP 7831 DI 10.1063/1.478689 PG 11 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 186QC UT WOS:000079739600023 ER PT J AU Schenter, GK Kathmann, SM Garrett, BC AF Schenter, GK Kathmann, SM Garrett, BC TI Variational transition state theory of vapor phase nucleation SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID MONTE-CARLO SIMULATION; MOLECULAR THEORY; PHYSICAL CLUSTERS; HOMOGENEOUS NUCLEATION; LIQUID; WATER; DYNAMICS; MODEL; DIMER AB An expression for the rate of vapor phase nucleation is developed that is based on variational transition state theory. The method depends on a definition of a dividing surface in phase space that separates reactants from products. For this surface we choose a spherical shell in coordinate space that is centered about the center of mass of a cluster of i molecules having an interior volume v. In a manner that is consistent with variational transition state theory, we vary v to minimize the reactive flux through our chosen dividing surface. The resulting expression for the rate constant involves a definition of a physical cluster that is consistent with previous developments in nucleation theory. In formulating the rate in this manner we obtain a new expression for the evaporation rate constant that is proportional to the derivative with respect to v of the Helmholtz free energy for cluster formation. In addition, we have a fundamentally justified procedure for selecting a unique volume v for each i cluster. Application of the method to the nucleation of water clusters will be presented. (C) 1999 American Institute of Physics. [S0021-9606(99)50316-4]. C1 Pacific NW Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Schenter, GK (reprint author), Pacific NW Lab, Environm Mol Sci Lab, POB 999, Richland, WA 99352 USA. RI Garrett, Bruce/F-8516-2011; Schenter, Gregory/I-7655-2014 OI Schenter, Gregory/0000-0001-5444-5484 NR 54 TC 41 Z9 41 U1 2 U2 12 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD APR 22 PY 1999 VL 110 IS 16 BP 7951 EP 7959 DI 10.1063/1.478727 PG 9 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 186QC UT WOS:000079739600035 ER PT J AU Franzen, S Moore, LJ Woodruff, WH Boxer, SG AF Franzen, S Moore, LJ Woodruff, WH Boxer, SG TI Stark-effect spectroscopy of the heme charge-transfer bands of deoxymyoglobin SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Letter ID CARBONMONOXY-MYOGLOBIN; PROTEINS; HEMOGLOBIN; DYNAMICS; PHOTODISSOCIATION; ABSORPTION; RELAXATION; BINDING AB We report the Stark spectra of the Soret, Q, and charge-transfer bands of deoxymyoglobin. The data show that band In: has charge-transfer character but that the magnitude of the charge displacement is significantly smaller than expected or than what is observed for band I or even the Soret or Q bands. The data also show that Symmetry breaking of iron-protoporphyrin LX in myoglobin produces a larger difference dipole moment in the Soret transition when compared to the dimethyl-ester of protoporphyrin IX. The results lend further credence to the hypothesis that the electrostatic environment of the heme pocket in myoglobin is important in modifying the properties of the heme transitions, and they provide a basis for quantitative analysis of the static and time-dependent band shifts observed in response to environmental electrostatic perturbations and ligand binding dynamics. C1 Stanford Univ, Dept Chem, Stanford, CA 94305 USA. Univ Calif Los Alamos Natl Lab, Biosci & Biotechnol Grp, Los Alamos, NM 87545 USA. RP Boxer, SG (reprint author), Stanford Univ, Dept Chem, Stanford, CA 94305 USA. NR 24 TC 11 Z9 11 U1 0 U2 1 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 APR 22 PY 1999 VL 103 IS 16 BP 3070 EP 3072 DI 10.1021/jp9848288 PG 3 WC Chemistry, Physical SC Chemistry GA 189YP UT WOS:000079934200005 ER PT J AU Asbury, JB Ellingson, RJ Ghosh, HN Ferrere, S Nozik, AJ Lian, TQ AF Asbury, JB Ellingson, RJ Ghosh, HN Ferrere, S Nozik, AJ Lian, TQ TI Femtosecond IR study of excited-state relaxation and electron-injection dynamics of Ru(dcbpy)(2)(NCS)(2) in solution and on nanocrystalline TiO2 and Al2O3 thin films SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID TITANIUM-DIOXIDE FILMS; RU-DYE MOLECULES; INFRARED-SPECTROSCOPY; CHARGE SEPARATION; SENSITIZING DYE; PHOTOSENSITIZATION; NANOPARTICLES; NANOCLUSTERS; INTERFACES; ABSORPTION AB The photophysics and electron injection dynamics of Ru(dcbpy)(2)(NCS)(2) [dcbpy = (4,4'-dicarboxy-2,2'-bipyridine)] (or Ru N3) in solution and adsorbed on nanocrystalline Al2O3 and TiO2 thin films were studied: by femtosecond mid-IR spectroscopy. For Ru N3 in ethanol after 400 nm excitation, the long-lived metal-to-ligand charge transfer ((MLCT)-M-3) excited state with CN stretching bands at 2040 cm(-1) was formed in less than 100 fs. No further decay of the excited-state absorption was observed within 1 ns consistent with the previously known 59 ns lifetime. For Ru N3 absorbed on Al2O3, an insulating substrate, the 3MLCT state was also formed in less than 100 fs. In contrast to Ru N3 in ethanol, this:excited state decayed by 50% within 1 ns via multiple exponential decay while no ground-state recovery was observed. This decay is attributed to electron transfer to surface states in the band gap of Al2O3 nanoparticles. For Ru N3 adsorbed onto the surface of TiO2, the transient mid-IR signal was dominated by the TR absorption of injected electrons in TiO2 in the 1700-2400 cm(-1) region. The rise time of the IR signal can be fitted by biexponential rise functions: 50 +/- 25 fs(>84%) and 1.7 +/- 0.5 ps (<16%) after deconvolution of instrument response function determined in a thin silicon wafer. Because of the scattering of the pump photon in the porous TiO2 thin film, the instrument response may be slightly lengthened, which may require a faster rise time for the first component to fit the data. The first component is assigned to the electron injection from the Ru N3 excited state to TiO2. The amplitude of the slower component appears to vary with samples ranging from ca. 16% in new samples to <5% in aged samples. The subsequent dynamics of the injected electrons have also been monitored by the decay of the IR signal. The observed 20% decay in amplitude within 1 ns was attributed to electron trapping dynamics in the thin films. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. Emory Univ, Dept Chem, Atlanta, GA 30322 USA. RP Nozik, AJ (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. RI Ellingson, Randy/H-3424-2013; Lian, Tianquan/L-8992-2013; Ghosh, Hirendra/J-8776-2012; Nozik, Arthur/A-1481-2012; Nozik, Arthur/P-2641-2016 OI Lian, Tianquan/0000-0002-8351-3690; NR 46 TC 332 Z9 333 U1 9 U2 87 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 APR 22 PY 1999 VL 103 IS 16 BP 3110 EP 3119 DI 10.1021/jp983915x PG 10 WC Chemistry, Physical SC Chemistry GA 189YP UT WOS:000079934200011 ER PT J AU Helms, V Straatsma, TP McCammon, JA AF Helms, V Straatsma, TP McCammon, JA TI Internal dynamics of green fluorescent protein SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID MOLECULAR-DYNAMICS; SYSTEM; CHROMOPHORE; SIMULATION; PROGRAM; MOTION AB A 1 ns molecular dynamics simulation was performed to study the dynamic behavior of wild-type green fluorescent protein from Aequorea victoria. We find the protein to be remarkably rigid, both overall, because the cylindrical beta-barrel provides a stable framework, but also on an atomic level in the immediate surrounding of the chromophore. Here, a tight H-bond network is formed mainly involving six internal water molecules. The perfect barrel is interrupted only between beta-strands 7 and 8 where contact is made via side chain interactions, and we investigated the dynamic behavior of this region in detail. After ca. 320 ps of simulation, an arginine residue, initially sticking out into solution, folded over the cleft to form a H-bond with a backbone oxygen atom on the opposite strand. This contact appears important for stabilization of the overall protein architecture. C1 Univ Calif San Diego, Dept Biochem & Chem, La Jolla, CA 92093 USA. Univ Calif San Diego, Dept Pharmacol, La Jolla, CA 92093 USA. Pacific NW Lab, Theory Modeling & Simulat Environm Mol Sci Lab, Richland, WA 99352 USA. RP Helms, V (reprint author), Max Planck Inst Biophys, Kennedyallee 70, D-60596 Frankfurt, Germany. OI Helms, Volkhard/0000-0002-2180-9154 NR 34 TC 62 Z9 62 U1 1 U2 16 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5647 J9 J PHYS CHEM B JI J. Phys. Chem. B PD APR 22 PY 1999 VL 103 IS 16 BP 3263 EP 3269 DI 10.1021/jp983120q PG 7 WC Chemistry, Physical SC Chemistry GA 189YP UT WOS:000079934200032 ER PT J AU Chen, LX Lee, PL Gosztola, D Svec, WA Montano, PA Wasielewski, MR AF Chen, LX Lee, PL Gosztola, D Svec, WA Montano, PA Wasielewski, MR TI Time-resolved X-ray absorption determination of structural changes following photoinduced electron transfer within bis-porphyrin heme protein models SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID DRIVING-FORCE; SPECTROSCOPY; ENERGY; STATE; CARBOXYMYOGLOBIN; TEMPERATURE; DEPENDENCE; COMPLEXES; MOLECULES; MYOGLOBIN AB Time domain energy dispersive X-ray absorption spectroscopy provides a powerful probe of changes in molecular structure that occur during photoinduced electron transfer reactions. In this study a diporphyrin model for electron transfer within modified heme proteins is examined using this technique. Transient optical absorption experiments show that photoinduced electron transfer from the lowest excited triplet state of a Zn, porphyrin attached at a fixed 25 Angstrom distance by means of a long spacer molecule to an Fe(III) porphyrin occurs with a 6 ms time constant at 77 K. Time domain X-ray absorption measurements are consistent with transient reduction of Fe(III) to Fe(II) that is accompanied by substantial weakening of the bond between the Fe atom and a pyridine molecule ligated to it. Coupling of ligand loss to reduction of Fe(III) to Fe(II) provides a means of stabilizing the reduced intermediate. C1 Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. Argonne Natl Lab, Expt Facil Div, Argonne, IL 60439 USA. Argonne Natl Lab, Div Sci Mat, Argonne, IL 60439 USA. Northwestern Univ, Dept Chem, Evanston, IL 60208 USA. RP Chen, LX (reprint author), Argonne Natl Lab, Div Chem, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Gosztola, David/D-9320-2011 OI Gosztola, David/0000-0003-2674-1379 NR 28 TC 27 Z9 27 U1 0 U2 5 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 APR 22 PY 1999 VL 103 IS 16 BP 3270 EP 3274 DI 10.1021/jp990056j PG 5 WC Chemistry, Physical SC Chemistry GA 189YP UT WOS:000079934200033 ER PT J AU Albright, CH Barr, SM AF Albright, CH Barr, SM TI Predicting quark and lepton masses and mixings SO PHYSICS LETTERS B LA English DT Article ID OSCILLATIONS; SO(10) AB A model is presented that fits the quark and lepton masses and mixings wherein five dimensionless parameters and a phase account for fifteen dimensionless observables. Among these are the Wolfenstein parameters rho and eta, the nu(e) - nu(mu) and nu(e) - nu(tau) mixing angles which are predicted to be small and comparable while the nu(mu) - nu(tau) mixing angle is predicted to be large. The model is based on supersymmetric SO(10) with the form of the mass matrices motivated by simplicity at the level of grand unification. (C) 1999 Published by Elsevier Science B.V. All rights reserved. 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. OI Albright, Carl/0000-0002-2252-6359 NR 18 TC 52 Z9 52 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 APR 22 PY 1999 VL 452 IS 3-4 BP 287 EP 293 DI 10.1016/S0370-2693(99)00290-7 PG 7 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 192HN UT WOS:000080072600014 ER PT J AU Rathsman, J AF Rathsman, J TI A generalised area law for hadronic string reinteractions SO PHYSICS LETTERS B LA English DT Article DE hadronisation; area law; string reinteraction ID RAPIDITY GAPS; E(+)E(-) ANNIHILATION; COLOR; DIS AB A new model for hadronic string reinteractions based on a generalised area law is presented. The model describes both the hadronic final states in e(+)e(-) annihilation and the diffractive structure function in deep inelastic scattering. The model: also predicts a shift in the W-mass reconstructed from hadronic decays of W-pairs of the order 65 MeV. (C) 1999 Published by Elsevier Science B.V. All rights reserved. C1 Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Rathsman, J (reprint author), Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. NR 29 TC 66 Z9 66 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 APR 22 PY 1999 VL 452 IS 3-4 BP 364 EP 371 DI 10.1016/S0370-2693(99)00291-9 PG 8 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 192HN UT WOS:000080072600023 ER PT J AU Takeuchi, Y Okumura, K Kajita, T Tasaka, S Nemoto, M Fukuda, Y Okazawa, H Hayakawa, T Ishihara, K Ishino, H Itow, Y Kameda, J Kasuga, S Kobayashi, K Kobayashi, U Koshio, Y Miura, M Nakahata, M Nakayama, S Obayashi, Y Okada, A Sakurai, N Shiozawa, M Suzuki, Y Takeuchi, H Totsuka, Y Yamada, S Earl, M Habig, A Kearns, E Messier, MD Scholberg, K Stone, JL Sulak, LR Walter, CW Goldhaber, M Barszczak, T Casper, D Gajewski, W Kropp, WR Mine, S Price, LR Smy, M Sobel, HW Vagins, MR Matsuno, S Stenger, VJ Takemori, D Ishii, T Kanzaki, J Kobayashi, T Ganezer, KS Keig, WE Ellsworth, RW Kibayashi, A Learned, JG Nakamura, K Nishikawa, K Oyama, Y Sakai, A Sakuda, M Sasaki, O Echigo, S Kohama, M Suzuki, AT Haines, TJ Blaufuss, E Kim, BK Sanford, R Svoboda, R Chen, ML Goodman, JA Sullivan, GW Hill, J Jung, CK Martens, K Mauger, C McGrew, C Sharkey, E Viren, B Yanagisawa, C Doki, W Kirisawa, M Inaba, S Miyano, K Saji, C Takahashi, M Takahata, M Higuchi, K Nagashima, Y Takita, M Yamaguchi, T Yoshida, M Kim, SB Etoh, M Hasegawa, A Hasegawa, T Hatakeyama, S Inoue, K Iwamoto, T Koga, N Maruyama, T Ogawa, H Shirai, J Suzuki, A Tsushima, F Koshiba, M Hatakeyama, Y Koike, M Nishijima, K Fujiyasu, H Futagami, T Hayato, Y Kanaya, Y Kaneyuki, K Watanabe, Y Kielczewska, D George, JS Stachyra, AL Wai, LL Wilkes, RJ Young, KK AF Takeuchi, Y Okumura, K Kajita, T Tasaka, S Nemoto, M Fukuda, Y Okazawa, H Hayakawa, T Ishihara, K Ishino, H Itow, Y Kameda, J Kasuga, S Kobayashi, K Kobayashi, U Koshio, Y Miura, M Nakahata, M Nakayama, S Obayashi, Y Okada, A Sakurai, N Shiozawa, M Suzuki, Y Takeuchi, H Totsuka, Y Yamada, S Earl, M Habig, A Kearns, E Messier, MD Scholberg, K Stone, JL Sulak, LR Walter, CW Goldhaber, M Barszczak, T Casper, D Gajewski, W Kropp, WR Mine, S Price, LR Smy, M Sobel, HW Vagins, MR Matsuno, S Stenger, VJ Takemori, D Ishii, T Kanzaki, J Kobayashi, T Ganezer, KS Keig, WE Ellsworth, RW Kibayashi, A Learned, JG Nakamura, K Nishikawa, K Oyama, Y Sakai, A Sakuda, M Sasaki, O Echigo, S Kohama, M Suzuki, AT Haines, TJ Blaufuss, E Kim, BK Sanford, R Svoboda, R Chen, ML Goodman, JA Sullivan, GW Hill, J Jung, CK Martens, K Mauger, C McGrew, C Sharkey, E Viren, B Yanagisawa, C Doki, W Kirisawa, M Inaba, S Miyano, K Saji, C Takahashi, M Takahata, M Higuchi, K Nagashima, Y Takita, M Yamaguchi, T Yoshida, M Kim, SB Etoh, M Hasegawa, A Hasegawa, T Hatakeyama, S Inoue, K Iwamoto, T Koga, N Maruyama, T Ogawa, H Shirai, J Suzuki, A Tsushima, F Koshiba, M Hatakeyama, Y Koike, M Nishijima, K Fujiyasu, H Futagami, T Hayato, Y Kanaya, Y Kaneyuki, K Watanabe, Y Kielczewska, D George, JS Stachyra, AL Wai, LL Wilkes, RJ Young, KK TI Measurement of radon concentrations at Super-Kamiokande SO PHYSICS LETTERS B LA English DT Article DE radon; Rn; Super-Kamiokande; neutrino AB Radioactivity from radon is a major background for observing solar neutrinos at Super-Kamiokande. In this paper, we describe the measurement of radon concentrations at Super-Kamiokande, the method of radon reduction, and the radon monitoring system. The measurement shows that the current low-energy event rate between 5.0 MeV and 6.5 MeV implies a radon concentration in the Super-Kamiokande water of less than 1.4 mBq/m(3). (C) 1999 Published by Elsevier Science B.V. All rights reserved. C1 Univ Tokyo, Inst Cosm Ray Res, Tanashi, Tokyo 1888502, Japan. Boston Univ, Dept Phys, Boston, MA 02215 USA. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Univ Calif Irvine, Dept Phys & Astron, Irvine, CA 92697 USA. Calif State Univ Dominguez Hills, Dept Phys, Carson, CA 90747 USA. George Mason Univ, Dept Phys, Fairfax, VA 22030 USA. Gifu Univ, Dept Phys, Gifu 5011193, Japan. Univ Hawaii, Dept Phys & Astron, Honolulu, HI 96822 USA. Inst Particle & Nucl Studies, High Energy Accelerator Res Org KEK, Ibaraki, Osaka 3050801, Japan. Kobe Univ, Dept Phys, Kobe, Hyogo 6578501, Japan. Univ Calif Los Alamos Natl Lab, Div Phys, Los Alamos, NM 87544 USA. Louisiana State Univ, Dept Phys & Astron, Baton Rouge, LA 70803 USA. Univ Maryland, Dept Phys, College Pk, MD 20742 USA. SUNY Stony Brook, Dept Phys & Astron, Stony Brook, NY 11794 USA. Niigata Univ, Dept Phys, Niigata 9502181, Japan. Osaka Univ, Dept Phys, Toyonaka, Osaka 5600043, Japan. Seoul Natl Univ, Dept Phys, Seoul 151742, South Korea. Tohoku Univ, Dept Phys, Sendai, Miyagi 9808578, Japan. Univ Tokyo, Tokyo 1130033, Japan. Tokai Univ, Dept Phys, Hiratsuka, Kanagawa 2591292, Japan. Tokyo Inst Technol, Dept Phys, Meguro Ku, Tokyo 1528551, Japan. Univ Warsaw, Inst Expt Phys, PL-00681 Warsaw, Poland. Univ Washington, Dept Phys, Seattle, WA 98195 USA. RP Takeuchi, Y (reprint author), Univ Tokyo, Inst Cosm Ray Res, Tanashi, Tokyo 1888502, Japan. RI Obayashi, Yoshihisa/A-4472-2011; Takeuchi, Yasuo/A-4310-2011; Nakamura, Kenzo/F-7174-2010; Sobel, Henry/A-4369-2011; Suzuki, Yoichiro/F-7542-2010; Martens, Kai/A-4323-2011; Wilkes, R.Jeffrey/E-6011-2013; Kim, Soo-Bong/B-7061-2014; Sakurai, Nobuyuki/M-5009-2014; Ishino, Hirokazu/C-1994-2015; Koshio, Yusuke/C-2847-2015; Kibayashi, Atsuko/K-7327-2015 OI Sakurai, Nobuyuki/0000-0002-1002-217X; Ishino, Hirokazu/0000-0002-8623-4080; Koshio, Yusuke/0000-0003-0437-8505; NR 9 TC 21 Z9 22 U1 0 U2 3 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 APR 22 PY 1999 VL 452 IS 3-4 BP 418 EP 424 DI 10.1016/S0370-2693(99)00311-1 PG 7 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA 192HN UT WOS:000080072600031 ER PT J AU Chalmers, G Rocek, M Wiles, S AF Chalmers, G Rocek, M Wiles, S TI Degeneration of ALF D-n metrics SO JOURNAL OF HIGH ENERGY PHYSICS LA English DT Article DE nonperturbative effects; duality in gauge field theories; D-branes; differential and algebraic geometry ID GAUGE-THEORIES; MONOPOLES AB Beginning with the Legendre transform construction of hyperkahler metrics, we analyze the ALF version of the D-n metrics. We determine the constraint equation obtained from extremizing the w coordinate of the generating function F(z, (z) over bar, u, (u) over bar, w) and study its behavior as we send two of the mass parameters of the Dn metric to zero. We find that the constraint equation enforces the limit that the metric becomes that of multi-Taub-NUT. C1 Argonne Natl Lab, Div High Energy Phys, Argonne, IL 60439 USA. SUNY Stony Brook, Inst Theoret Phys, Stony Brook, NY 11794 USA. RP Chalmers, G (reprint author), Argonne Natl Lab, Div High Energy Phys, 9700 S Cass Ave, Argonne, IL 60439 USA. EM chalmers@sgi2.hep.anl.gov; rocek@insti.physics.sunysb.edu; swiles@insti.physics.sunysb.edu NR 15 TC 9 Z9 9 U1 0 U2 0 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1029-8479 J9 J HIGH ENERGY PHYS JI J. High Energy Phys. PD APR 21 PY 1999 IS 1 AR 009 PG 14 WC Physics, Particles & Fields SC Physics GA 200CV UT WOS:000080522800009 ER PT J AU Csaki, C Ooguri, H Oz, Y Terning, J AF Csaki, C Ooguri, H Oz, Y Terning, J TI Glueball mass spectrum from supergravity SO JOURNAL OF HIGH ENERGY PHYSICS LA English DT Article DE p-branes; D-branes ID N GAUGE-THEORY; YANG-MILLS THEORY; STRING THEORY; FINITE-TEMPERATURE; FIELD-THEORIES; SIGMA-MODEL; ABSORPTION; BRANES; LIMIT; N=4 AB We calculate the spectrum of glueball masses in non-supersymmetric Yang-Mills theory in three and four dimensions, based on a conjectured duality between supergravity and large N gauge theories. The glueball masses are obtained by solving supergravity wave equations in a black hole geometry. We find that the mass ratios are in good numerical agreement with the available lattice data. We also compute the leading (g(YM)(2)N)(-1) corrections to the glueball masses, by taking into account stringy corrections to the supergravity action and to the black hole metric. We find that the corrections to the masses are negative and of order (g(YM)(2)N)(-3/2). Thus for a fixed ultraviolet cutoff the masses decrease as we decrease the 't Hooft coupling, in accordance with our expectation about the continuum limit of the gauge theories. C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Theoret Phys Grp, Berkeley, CA 94720 USA. Univ Calif Santa Barbara, Inst Theoret Phys, Santa Barbara, CA 93106 USA. RP Csaki, C (reprint author), Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. EM csaki@thwk5.lbl.gov; ooguri@thsrv.lbl.gov; Yaron.Oz@cern.ch; terning@alvin.lbl.gov RI Ooguri, Hirosi/A-4407-2011 NR 38 TC 186 Z9 186 U1 0 U2 0 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1029-8479 J9 J HIGH ENERGY PHYS JI J. High Energy Phys. PD APR 21 PY 1999 IS 1 AR 017 PG 21 WC Physics, Particles & Fields SC Physics GA 200CV UT WOS:000080522800017 ER PT J AU Faber, M Greensite, J Olejnik, S AF Faber, M Greensite, J Olejnik, S TI Center projection with and without gauge fixing SO JOURNAL OF HIGH ENERGY PHYSICS LA English DT Article DE solitons monopoles and instantons; confinement; lattice gauge field theories ID STRING BREAKING; MATTER FIELDS; CONFINEMENT; VORTICES; DOMINANCE; VACUUM AB We consider projections of SU(2) lattice link variables onto Z(2) center and U(1) subgroups, with and without gauge-fixing. It is shown that in the absence of gauge-fixing, and up to an additive constant, the static quark potential extracted from projected variables agrees exactly with the static quark potential taken from the full link variables; this is an extension of recent arguments by Ambjorn and Greensite, and by Ogilvie. Abelian and center dominance is essentially trivial in this case, and seems of no physical relevance. The situation changes drastically upon gauge fixing. In the case of center projection, there are a series of tests one can carry out, to check if vortices identified in the projected configurations are physical objects. All these criteria are satisfied in maximal center gauge, and we show here that they all fail in the absence of gauge fixing. The non-triviality of center projection is due entirely to the maximal center gauge-fixing, which pumps information about the location of extended physical objects into local Z(2) observables. C1 Vienna Univ Technol, Inst Kernphys, A-1040 Vienna, Austria. San Francisco State Univ, Dept Phys & Astron, San Francisco, CA 94117 USA. Lawrence Berkeley Lab, Theory Grp, Berkeley, CA 94720 USA. Slovak Acad Sci, Inst Phys, SK-84288 Bratislava, Slovakia. RP Faber, M (reprint author), Vienna Univ Technol, Inst Kernphys, A-1040 Vienna, Austria. EM faber@kph.tuwien.ac.at; greensit@stars.sfsu.edu; fyziolej@savba.sk RI Olejnik, Stefan/C-6145-2008 OI Olejnik, Stefan/0000-0002-0910-7125 NR 25 TC 6 Z9 6 U1 0 U2 0 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1029-8479 J9 J HIGH ENERGY PHYS JI J. High Energy Phys. PD APR 21 PY 1999 IS 1 PG 20 WC Physics, Particles & Fields SC Physics GA 200CV UT WOS:000080522800008 ER PT J AU Kachru, S Silverstein, E AF Kachru, S Silverstein, E TI On vanishing two loop cosmological constants in nonsupersymmetric strings SO JOURNAL OF HIGH ENERGY PHYSICS LA English DT Article DE superstring vacua; superstrings and heterotic strings; supersymmetry breaking ID MULTILOOP SUPERSTRING AMPLITUDES; CHIRAL BOSONIZATION; PERTURBATION-THEORY; SUPERSYMMETRY; INVARIANCE; SURFACE; GAUGE AB It has recently been suggested that in certain special nonsupersymmetric type II string compactifications, at least the first two perturbative contributions to the cosmological constant Lambda vanish. Support for perturbative vanishing beyond 1-loop (as well as evidence for the absence of some nonperturbative contributions) has come from duality arguments. There was also a direct 2-loop computation which was incomplete; in this note we explain the deficiency of the previous 2-loop calculation and discuss the complete 2-loop computation in two different models. The corrected analysis yields a vanishing 2-loop contribution to Lambda in these models. C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Ernest Orlando Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Kachru, S (reprint author), Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. EM kachru@thsrv.lbl.gov; evas@slac.stanford.edu NR 21 TC 18 Z9 18 U1 0 U2 0 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1029-8479 J9 J HIGH ENERGY PHYS JI J. High Energy Phys. PD APR 21 PY 1999 IS 1 AR 004 PG 15 WC Physics, Particles & Fields SC Physics GA 200CV UT WOS:000080522800004 ER PT J AU Larsen, FH Lipton, AS Jakobsen, HJ Nielsen, NC Ellis, PD AF Larsen, FH Lipton, AS Jakobsen, HJ Nielsen, NC Ellis, PD TI Zn-67 QCPMG solid-state NMR studies of zinc complexes as models for metalloproteins SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID NUCLEAR-MAGNETIC-RESONANCE; CD-113 SHIELDING TENSORS; FOURIER-TRANSFORM NMR; CADMIUM COMPOUNDS; SPECTROSCOPY; MYOGLOBIN; CRYSTAL C1 Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. Univ Aarhus, Dept Chem, Instrument Ctr Solid State NMR Spect, DK-8000 Aarhus C, Denmark. RP Ellis, PD (reprint author), Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RI Larsen, Flemming/A-5255-2015 OI Larsen, Flemming/0000-0001-5180-6870 NR 28 TC 52 Z9 53 U1 0 U2 10 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 APR 21 PY 1999 VL 121 IS 15 BP 3783 EP 3784 DI 10.1021/ja9839623 PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA 189YV UT WOS:000079934900028 ER PT J AU Dai, S Ju, YH Barnes, CE AF Dai, S Ju, YH Barnes, CE TI Solvent extraction of strontium nitrate by a crown ether using room-temperature ionic liquids SO JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS LA English DT Article ID CHLORIDE; MELT AB The preliminary results described here show that unprecedentedly large distribution coefficient (D) values can be achieved using ionic liquids as extraction solvents for the separation of metal ions by crown ethers. This work highlights the vast opportunities in separation applications for ionic liquids with crown ethers. C1 Oak Ridge Natl Lab, Div Chem Technol, Oak Ridge, TN 37831 USA. Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. RP Dai, S (reprint author), Oak Ridge Natl Lab, Div Chem Technol, POB 2008, Oak Ridge, TN 37831 USA. RI Dai, Sheng/K-8411-2015 OI Dai, Sheng/0000-0002-8046-3931 NR 20 TC 462 Z9 472 U1 11 U2 87 PU ROYAL SOC CHEMISTRY PI CAMBRIDGE PA THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD,, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND SN 0300-9246 J9 J CHEM SOC DALTON JI J. Chem. Soc.-Dalton Trans. PD APR 21 PY 1999 IS 8 BP 1201 EP 1202 DI 10.1039/a809672d PG 2 WC Chemistry, Inorganic & Nuclear SC Chemistry GA 191LY UT WOS:000080024900002 ER PT J AU Whitener, GD Hagadorn, JR Arnold, J AF Whitener, GD Hagadorn, JR Arnold, J TI Synthesis and characterization of a new class of chelating bis(amidinate) ligands SO JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS LA English DT Article ID ETHYLENE POLYMERIZATION CATALYSTS; BRIDGED TETRAHYDROINDENYL LIGANDS; ANSA-METALLOCENE DERIVATIVES; LOW-VALENT CHEMISTRY; OLEFIN POLYMERIZATION; HETEROALLYLIC LIGANDS; ASYMMETRIC CATALYSIS; CRYSTAL-STRUCTURES; AMIDINATE LIGANDS; ALKYL DERIVATIVES AB A series of diamidines based on trans-1,2-diaminocyclohexane have been prepared. Reactions of trans-1,2-diaminocyclohexane with a variety of aryl acid chlorides yields the corresponding diamides in very high (91-95%) yield. Conversion of the diamides to the diimine chloride is carried out by treatment with PCl5 in CH2Cl2. Reaction of the diimine chloride with aniline in CH2Cl2 finally yields the diamidine in good yields on multi-gram scales. Alternatively, a one-pot reaction between the diamide, PCl5 and aniline gives the products, although yields are generally lower. The solid-state structure of the unsubstituted diamidine shows localized C-N single and double bonds in the amidine moiety; intra- and inter-molecular hydrogen bonding is also observed between amidine groups. Alkali metal derivatives (M = Li, Na, K) were prepared by reaction of the diamidines with either (BuLi)-Bu-n or MN(SiMe3)(2). Isolated yields of these alkali metal derivatives, which crystallize as thf adducts, are moderate (34-64%). X-Ray crystallography shows that in all cases the alkali metal atoms bridge the two amidinate groups within the same molecule, forming a C-2 symmetric eight-membered ring. Nonetheless, there are marked differences in coordination geometries of the series. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Lawrence Berkeley Natl Lab, Div Chem Sci, Berkeley, CA 94720 USA. RP Arnold, J (reprint author), Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. RI Arnold, John/F-3963-2012 OI Arnold, John/0000-0001-9671-227X NR 46 TC 74 Z9 74 U1 1 U2 5 PU ROYAL SOC CHEMISTRY PI CAMBRIDGE PA THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD,, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND SN 0300-9246 J9 J CHEM SOC DALTON JI J. Chem. Soc.-Dalton Trans. PD APR 21 PY 1999 IS 8 BP 1249 EP 1255 DI 10.1039/a809211g PG 7 WC Chemistry, Inorganic & Nuclear SC Chemistry GA 191LY UT WOS:000080024900011 ER PT J AU Li, Z Dezilllie, B Eremin, V Li, CJ Verbitskaya, E AF Li, Z Dezilllie, B Eremin, V Li, CJ Verbitskaya, E TI First charge collection and position-precision data on the medium-resistivity silicon strip detectors before and after neutron irradiation up to 2x10(14) n/cm(2) SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 2nd International Conference on Radiation Effects on Semiconductor Materials, Detectors and Devices CY MAR 04-06, 1998 CL FLORENCE, ITALY SP Univ Florence, Ist Nazl Fis Nucl DE strip detectors; silicon detectors; annealing; simulation; irradiation ID N-EFF; JUNCTION DETECTORS; RADIATION-DAMAGE; MODELS AB Test strip detectors of 125 mu m, 500 mu m, and 1 mm pitches with about 1 cm(2) areas have been made on medium-resistivity silicon wafers (1.3 and 2.7 k Ohm cm). Detectors of 500 mu m pitch have been tested for charge collection and position precision before and after neutron irradiation (up to 2 x 10(14) n/cm(2)) using 820 and 1030 nm laser lights with different beam-spot sizes. It has been found that for a bias of 250 V a strip detector made of 1.3 k Ohm cm (300 mu m thick) can be fully depleted before and after an irradiation of 2 x 10(14) n/cm(2). For a 500 mu m pitch strip detector made of 2.7 k Ohm cm tested with an 1030 nm laser light with 200 mu m spot size, the position reconstruction error is about 14 mu m before irradiation, and 17 mu m after about 1.7 x 10(13) n/cm(2) irradiation. We demonstrated in this work that medium resistivity silicon strip detectors can work just as well as the traditional high-resistivity ones, but with higher radiation tolerance. We also tested charge sharing and position reconstruction using a 1030 nm wavelength (300 mu m absorption length in Si at RT) laser, which provides a simulation of MIP particles in high-physics experiments in terms of charge collection and position reconstruction, (C) 1999 Elsevier Science B.V. All rights reserved. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. RAS, AF Ioffe Physicotech Inst, St Petersburg, Russia. Chinese Acad Sci, Inst Semicond, Beijing 100083, Peoples R China. RP Brookhaven Natl Lab, Bldg 535B,POB 5000, Upton, NY 11973 USA. EM zhengl@bnl.gov RI Verbitskaya, Elena/D-1521-2014 NR 15 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 APR 21 PY 1999 VL 426 IS 1 BP 38 EP 46 DI 10.1016/S0168-9002(98)01514-9 PG 9 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 190MJ UT WOS:000079966600007 ER PT J AU Chen, W Chien, CY Dezillie, B Eremin, V Li, Z Menichelli, D Xie, X AF Chen, W Chien, CY Dezillie, B Eremin, V Li, Z Menichelli, D Xie, X TI Electrical characterization of irradiated medium resistivity n(+)/n/p(+) pixel detectors SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 2nd International Conference on Radiation Effects on Semiconductor Materials, Detectors and Devices CY MAR 04-06, 1998 CL FLORENCE, ITALY SP Univ Florence, Ist Nazl Fis Nucl DE electrical characterization; n(+)/n/p(+) pixel detectors ID SILICON DETECTORS; LHC APPLICATION; DESIGN; CONFIGURATIONS; TOLERANCE; N/CM(2) AB Several n(+)/n/p(+) pixel detectors with medium resistivity (rho = 1.9 k Ohm cm) and reduced thickness (200 mu m) have been characterized after irradiation up to 5 x 10(14) n/cm(2), as an extension of measurements carried out in as-processed devices in the past. Results are really satisfactory: the leakage bulk current is quite low, and no breakdown is observed up to 300 V. which is the design bias in irradiated devices. Moreover, the use of medium resistivity material gives slightly higher radiation tolerance as compared with high resistivity case. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. Russian Acad Sci, AF Ioffe Physicotech Inst, St Petersburg, Russia. Dipartimento Energet Firenze, Florence, Italy. RP Li, Z (reprint author), Brookhaven Natl Lab, Bldg 535 B,POB 5000, Upton, NY 11973 USA. NR 9 TC 1 Z9 1 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD APR 21 PY 1999 VL 426 IS 1 BP 47 EP 50 DI 10.1016/S0168-9002(98)01496-X PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 190MJ UT WOS:000079966600008 ER PT J AU Pandey, SU Middelkamp, P Li, Z Eremin, V AF Pandey, SU Middelkamp, P Li, Z Eremin, V TI New experimental and analysis methods in I-DLTS SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 2nd International Conference on Radiation Effects on Semiconductor Materials, Detectors and Devices CY MAR 04-06, 1998 CL FLORENCE, ITALY SP Univ Florence, Ist Nazl Fis Nucl DE I-DLTS measurements; deconvolutions; I-DLTS spectra ID RESISTIVITY SILICON DETECTORS; LEVEL TRANSIENT SPECTROSCOPY; SEMICONDUCTORS; DEFECTS AB A simple modification to traditional experimental apparatus to perform I-DLTS measurements is presented. This setup is shown to be faster and more sensitive than traditional double boxcar I-DLTS systems. A novel analysis technique utilising multiple exponential fits to the I-DLTS signal from a highly neutron irradiated silicon sample is presented along with a discussion of the results. It is shown that the new method has better resolution and can deconvolute overlapping peaks more accurately than previous methods. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. Wayne State Univ, Detroit, MI USA. RAS, AF Ioffe Physicotech Inst, St Petersburg, Russia. RP Pandey, SU (reprint author), Brookhaven Natl Lab, Bldg 510A STAR, Upton, NY 11973 USA. NR 8 TC 5 Z9 5 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD APR 21 PY 1999 VL 426 IS 1 BP 109 EP 113 DI 10.1016/S0168-9002(98)01542-3 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 190MJ UT WOS:000079966600019 ER PT J AU Dezillie, B Eremin, V Li, Z AF Dezillie, B Eremin, V Li, Z TI Defect analysis of silicon detectors made of different materials for radiation hardness SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 2nd International Conference on Radiation Effects on Semiconductor Materials, Detectors and Devices CY MAR 04-06, 1998 CL FLORENCE, ITALY SP Univ Florence, Ist Nazl Fis Nucl ID RESISTIVITY AB A comparative study of the radiation hardness of single pad detectors, manufactured from standard float-zone (FZ) and epitaxial (Epi) n-type monocrystal silicon with comparable initial resistivity is presented. Detectors processed from FZ and Epi material with a low (400 Ohm cm and 500 Ohm cm) and a high (similar to 2 k Ohm cm) initial resistivity have been irradiated up to 4 x 10(14) n/cm(2) and measured under the same conditions in order to study the influence of the initial resistivity on the detector radiation hardness. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. Russian Acad Sci, AF Ioffe Physicotech Inst, St Petersburg, Russia. RP Dezillie, B (reprint author), Brookhaven Natl Lab, Bldg 535B, Upton, NY 11973 USA. NR 14 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 APR 21 PY 1999 VL 426 IS 1 BP 114 EP 119 DI 10.1016/S0168-9002(98)01477-6 PG 6 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 190MJ UT WOS:000079966600020 ER PT J AU Eremin, V Ivanov, A Verbitskaya, E Li, Z Pandey, SU AF Eremin, V Ivanov, A Verbitskaya, E Li, Z Pandey, SU TI Analysis of divacancy related traps induced by proton, neutron and gamma radiation in high resistivity silicon detectors SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 2nd International Conference on Radiation Effects on Semiconductor Materials, Detectors and Devices CY MAR 04-06, 1998 CL FLORENCE, ITALY SP Univ Florence, Ist Nazl Fis Nucl DE high-resistivity silicon detectors; DLTS spectra ID DAMAGE AB Defects with deep levels induced in high-resistivity silicon detectors by low and high radiation fluence of protons and neutrons are studied using capacitance and current DLTS. Numerical simulation of I-DLTS and C-DLTS spectra based on the model of charge carrier emission and redistribution of electric field in the detector enabled one to perform the detailed investigation of DLTS spectra. It has been shown that the main DLTS peak in the range of 200 to 260 K may be considered as a result of the interference of deep levels near the midgap - negatively charged divacancy VV- and the C-i-O-i complex. The model describing the broadening of the VV- component of the spectrum, which arises from the divacancy localization inside a cluster, is discussed. The results are compared with those obtained for gamma irradiation, for which the dominant contribution in DLTS spectra arises just from the C-i-O-i complex. (C) 1999 Published by Elsevier Science B.V. All rights reserved. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. Russian Acad Sci, AF Ioffe Physicotech Inst, St Petersburg 194021, Russia. Wayne State Univ, Detroit, MI USA. RP Brookhaven Natl Lab, Upton, NY 11973 USA. EM zhengl@bnlarm.bnl.gov RI Verbitskaya, Elena/D-1521-2014; Ivanov, Alexander/E-3993-2014 NR 9 TC 32 Z9 32 U1 0 U2 2 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 APR 21 PY 1999 VL 426 IS 1 BP 120 EP 125 DI 10.1016/S0168-9002(98)01479-X PG 6 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 190MJ UT WOS:000079966600021 ER PT J AU Pirollo, S Biggeri, U Borchi, E Bruzzi, M Catacchini, E Lazanu, S Li, Z Sciortino, S AF Pirollo, S Biggeri, U Borchi, E Bruzzi, M Catacchini, E Lazanu, S Li, Z Sciortino, S TI Radiation damage on p-type silicon detectors SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 2nd International Conference on Radiation Effects on Semiconductor Materials, Detectors and Devices CY MAR 04-06, 1998 CL FLORENCE, ITALY SP Univ Florence, Ist Nazl Fis Nucl AB Two sets of p-type silicon thigh resistivity bulk and low resistivity epitaxial) samples and one set of n(+)-p junctions have been irradiated with fast neutrons up to 8 x 10(13) cm(-2). I-V and C-V characteristics as well as Thermally Stimulated Currents (TSC) and Hall Effect (HE) analyses have been performed on the irradiated samples and diodes in view to determine the radiation-induced damage and the change in the electrical properties. A change in the effective carrier concentration and in the leakage current after irradiation similar to the one found for p(+)-n detectors has been observed in p-type diodes. An increase with the fluence of the resistivity and Hall coefficient was measured at room temperature both for the low and high resistivity sets. This evidence has been explained in terms of a two-level model taking into account a linear increase in concentration with the fluence of the main radiation-induced defects observed with TSC, probably related to divacancy and carbon-oxygen complex. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Ist Nazl Fis Nucl, I-50139 Florence, Italy. Univ Florence, Dipartimento Energet, I-50139 Florence, Italy. Inst Phys & Technol Mat, Bucharest, Romania. Brookhaven Natl Lab, Upton, NY 11973 USA. RP Pirollo, S (reprint author), Ist Nazl Fis Nucl, Via S Marta 3, I-50139 Florence, Italy. RI Lazanu, Sorina/B-7819-2012; Bruzzi, Mara/K-1326-2015; OI Lazanu, Sorina/0000-0003-0390-0779; Bruzzi, Mara/0000-0001-7344-8365; Sciortino, Silvio/0000-0003-0570-7489 NR 8 TC 8 Z9 8 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 APR 21 PY 1999 VL 426 IS 1 BP 126 EP 130 DI 10.1016/S0168-9002(98)01480-6 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 190MJ UT WOS:000079966600022 ER PT J AU Menichelli, D Bruzzi, M Li, Z Eremin, V AF Menichelli, D Bruzzi, M Li, Z Eremin, V TI Modelling of observed double-junction effect SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 2nd International Conference on Radiation Effects on Semiconductor Materials, Detectors and Devices CY MAR 04-06, 1998 CL FLORENCE, ITALY SP Univ Florence, Ist Nazl Fis Nucl DE TCT measurements; laser-injected electrons; double-junction effect ID SILICON DETECTORS; N-EFF AB New TCT measurements reveal the existence of a strong electric field, before full depletion, near both p(+) and n(+) side of high- and medium-resistivity silicon detectors, irradiated over space-charge sign inversion. More, by injecting carriers near the low-held side, double-peaked TCT current pulses are observed. This fact can be justified by assuming the presence of two deep levels in the gap. an acceptor like above mid-gap, and a donor like in the lower half of the gap, which can support the existence of two depleted regions. Particularly, the theoretical analysis of the TCT current profiles has been developed, and the second peak existence has been explained as the effect of carriers re-injection from ENB inside depleted regions. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Ist Nazl Fis Nucl, Dipartimento Energet S Stecco, I-50139 Florence, Italy. Brookhaven Natl Lab, Upton, NY 11973 USA. Russian Acad Sci, AF Ioffe Physicotech Inst, St Petersburg 194021, Russia. RP Menichelli, D (reprint author), Ist Nazl Fis Nucl, Dipartimento Energet S Stecco, Via S Marta 3, I-50139 Florence, Italy. RI Bruzzi, Mara/K-1326-2015 OI Bruzzi, Mara/0000-0001-7344-8365 NR 8 TC 49 Z9 49 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 APR 21 PY 1999 VL 426 IS 1 BP 135 EP 139 DI 10.1016/S0168-9002(98)01482-X PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 190MJ UT WOS:000079966600024 ER PT J AU Meier, D Adam, W Bauer, C Berdermann, E Bergonzo, P Bogani, F Borchi, E Bruzzi, M Colledani, C Conway, J Dabrowski, W Delpierre, P Deneuville, A Dulinski, W van Eijk, B Fallou, A Foulon, F Friedl, M Jany, C Gan, KK Gheeraert, E Grigoriev, E Hallewell, G Hall-Wilton, R Han, S Hartjes, F Hrubec, J Husson, D Kagan, H Kania, D Kaplon, J Kass, R Knopfle, KT Krammer, M Manfredi, PF Marshall, RD Mishina, M Le Normand, F Pan, LS Palmieri, VG Pernegger, H Pernicka, M Peitz, A Pirollo, S Pretzl, K Re, V Riester, JL Roe, S Roff, D Rudge, A Schnetzer, S Sciortino, S Speziali, V Stelzer, H Stone, R Tapper, RJ Tesarek, R Thomson, GB Trawick, M Trischuk, W Turchetta, R Walsh, AM Wedenig, R Weilhammer, P Ziock, H Zoeller, M AF Meier, D Adam, W Bauer, C Berdermann, E Bergonzo, P Bogani, F Borchi, E Bruzzi, M Colledani, C Conway, J Dabrowski, W Delpierre, P Deneuville, A Dulinski, W van Eijk, B Fallou, A Foulon, F Friedl, M Jany, C Gan, KK Gheeraert, E Grigoriev, E Hallewell, G Hall-Wilton, R Han, S Hartjes, F Hrubec, J Husson, D Kagan, H Kania, D Kaplon, J Kass, R Knopfle, KT Krammer, M Manfredi, PF Marshall, RD Mishina, M Le Normand, F Pan, LS Palmieri, VG Pernegger, H Pernicka, M Peitz, A Pirollo, S Pretzl, K Re, V Riester, JL Roe, S Roff, D Rudge, A Schnetzer, S Sciortino, S Speziali, V Stelzer, H Stone, R Tapper, RJ Tesarek, R Thomson, GB Trawick, M Trischuk, W Turchetta, R Walsh, AM Wedenig, R Weilhammer, P Ziock, H Zoeller, M CA RD42 Collaboration TI Proton irradiation of CVD diamond detectors for high-luminosity experiments at the LHC SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 2nd International Conference on Radiation Effects on Semiconductor Materials, Detectors and Devices CY MAR 04-06, 1998 CL FLORENCE, ITALY SP Univ Florence, Ist Nazl Fis Nucl DE position-sensitive detector; beam-induced current; luminosity; irradiation AB CVD diamond shows promising properties for use as a position-sensitive detector for experiments in the highest radiation areas at the Large Hadron Collider. In order to study the radiation hardness of diamond we exposed CVD diamond detector samples to 24 Gev/c and 500 Mev protons up to a fluence of 5 x 10(15) p/cm(2). We measured the charge collection distance, the average distance electron-hole pairs move apart in an external electric field, and leakage currents before, during, and after irradiation. The charge collection distance remains unchanged up to 1 x 10(15) p/cm(2) and decreases by approximate to 40% at 5 x 10(15) p/cm(2) Leakage currents of diamond samples were below 1 pA before and after irradiation. The particle-induced currents during irradiation correlate well with the proton flux. In contrast to diamond, a silicon diode, which was irradiated for comparison, shows the known large increase in leakage current. We conclude that CVD diamond detectors are radiation hard to 24 GeV/c and 500 MeV protons up to at least 1 x 10(15) p/cm(2) without signal loss. (C) 1999 Elsevier Science B.V. All rights reserved. C1 CERN, CH-1211 Geneva, Switzerland. Osterr Akad Wissensch, Inst Hochenergiephys, Vienna, Austria. MPI Kernphys, Heidelberg, Germany. GSI Darmstadt, D-6100 Darmstadt, Germany. Ctr Etud Saclay, F-91191 Gif Sur Yvette, France. LENS, Florence, Italy. Univ Florence, Florence, Italy. CRN, LEPSI, Strasbourg, France. Rutgers State Univ, Piscataway, NJ USA. CPPM, Marseille, France. LEPES, Grenoble, France. NIKHEF H, NL-1009 DB Amsterdam, Netherlands. Ohio State Univ, Columbus, OH 43210 USA. Univ Bristol, Bristol, Avon, England. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA USA. Univ Pavia, Dipartimento Elettron, Pavia, Italy. FNAL, Batavia, IL USA. Lab Hochenergiephys, Bern, Switzerland. Univ Toronto, Toronto, ON, Canada. Univ Calif Los Alamos Natl Lab, Los Alamos, NM USA. RP Meier, D (reprint author), CERN, RD42, CH-1211 Geneva, Switzerland. RI Krammer, Manfred/A-6508-2010; Grigoriev, Eugene/K-6650-2013; Bruzzi, Mara/K-1326-2015; Bergonzo, Philippe/A-6567-2015; Gheeraert, Etienne/E-8071-2015; OI Krammer, Manfred/0000-0003-2257-7751; Grigoriev, Eugene/0000-0001-7235-9715; Bruzzi, Mara/0000-0001-7344-8365; Bergonzo, Philippe/0000-0002-0647-9134; Gheeraert, Etienne/0000-0002-9952-5805; Re, Valerio/0000-0003-0697-3420; Sciortino, Silvio/0000-0003-0570-7489 NR 8 TC 50 Z9 51 U1 0 U2 5 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 APR 21 PY 1999 VL 426 IS 1 BP 173 EP 180 DI 10.1016/S0168-9002(98)01488-0 PG 8 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 190MJ UT WOS:000079966600030 ER PT J AU Egorov, N Eremin, V Golubkov, S Konkov, K Kozlov, Y Li, Z Sidorov, A AF Egorov, N Eremin, V Golubkov, S Konkov, K Kozlov, Y Li, Z Sidorov, A TI Operation of guard rings on the ohmic side of n(+)-p-p(+) diodes SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 2nd International Conference on Radiation Effects on Semiconductor Materials, Detectors and Devices CY MAR 04-06, 1998 CL FLORENCE, ITALY SP Univ Florence, Ist Nazl Fis Nucl DE detectors; MGR structures; n(+)-p-p(+) diodes ID PLANAR DEVICES; FIELD PLATE; STABILIZATION; DETECTORS AB Detectors from high-resistivity p-type silicon with multi guard rings structure located on the ohmic side have been investigated. The processed detectors were constructed with four p(+)-rings surrounding the central p(+)-pad. The n(+)-p junction opposite to the contact with rings had not any protection and was cut-through by chip scribing. Investigation of the potential distribution between the floating p(+)-rings has shown that the potential difference arises just after the depletion of the detector bulk and is accompanied by the detector leakage current saturation. The saturated current is mainly a leakage current flowing in a scribed periphery. Grounding of one of the p(+)-rings to collect the detector leakage current allows the separation of the bulk and the surface components of the current, which reduces the current of a central p(+)-pad contact down to tens nA/cm(2). A model based on the field effect in the gap between the neighboring p(+)-rings is proposed. The experiments carried out in this study show that construction of the ohmic side of Si detectors with multi guard rings is a perspective approach to design the detectors operational at high biases. Detectors processed in this way allow one to apply biases up to 600 V. (C) 1999 Published by Elsevier Science B.V. All rights reserved. C1 Russian Acad Sci, AF Ioffe Physicotech Inst, St Petersburg 196140, Russia. Russian Inst Mat Sci & Technol, Zelenograd, Russia. Brookhaven Natl Lab, Upton, NY 11973 USA. RP Eremin, V (reprint author), Russian Acad Sci, AF Ioffe Physicotech Inst, St Petersburg 196140, Russia. NR 8 TC 4 Z9 4 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 APR 21 PY 1999 VL 426 IS 1 BP 197 EP 205 DI 10.1016/S0168-9002(98)01492-2 PG 9 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA 190MJ UT WOS:000079966600034 ER PT J AU Kehler, BA Baker, NP Lee, DH Maggiore, CJ Nastasi, M Tesmer, JR Walter, KC Nakamura, Y Ullrich, BM AF Kehler, BA Baker, NP Lee, DH Maggiore, CJ Nastasi, M Tesmer, JR Walter, KC Nakamura, Y Ullrich, BM TI Tribological behavior of high-density polyethylene in dry sliding contact with ion-implanted CoCrMo SO SURFACE & COATINGS TECHNOLOGY LA English DT Article DE dry sliding; high-density polyethylene; ion-implanted CoCrMo ID DIAMOND; CARBON; FILMS AB The surface of a CoCrMo alloy has been modified using beamline ion implantation of boron, carbon and nitrogen, and diamond-like carbon (DLC) deposition. All surface treatments, with the exception of high-dose nitrogen-ion implantation, result in an increase in surface hardness. However, wear and friction either remain similar to, or become worse than, those of the unimplanted alloy. Experiments show that adhesion energy and energy of deformation are the two major components influencing the frictional behavior of the CoCrMo-high-density polyethylene (HDPE) wear system. Wear was dominated by material loss in the HDPE pin. No correlation between wear and CoCrMo hardness was observed, indicating that adhesion or plowing in HDPE pins is not correlated with the mechanical properties of the counterface materials. A comparison of the ion-implanted samples with DLC-coated CoCrMo showed the KDPE-DLC sliding system to have the largest coefficient of friction. The friction behavior of this system was found to be controlled by an adhesive build-up of HDPE on the DLC surface. (C) 1999 Elsevier Science S.A. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. Kagoshima Univ, Dept Mech Engn, Kagoshima 8900065, Japan. Univ Calif Los Alamos Natl Lab, Ion Beam Mat Lab, Los Alamos, NM 87545 USA. RP Nastasi, M (reprint author), Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. NR 20 TC 6 Z9 6 U1 1 U2 5 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0257-8972 J9 SURF COAT TECH JI Surf. Coat. Technol. PD APR 21 PY 1999 VL 114 IS 1 BP 19 EP 28 DI 10.1016/S0257-8972(99)00030-4 PG 10 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA 201BB UT WOS:000080573800004 ER PT J AU Thompson, DC Busch, GE Hewitt, CJ Remelius, DK Shimada, T Strauss, CEM Wilson, CW Zaugg, TJ AF Thompson, DC Busch, GE Hewitt, CJ Remelius, DK Shimada, T Strauss, CEM Wilson, CW Zaugg, TJ TI High-speed random access laser tuning SO APPLIED OPTICS LA English DT Article ID FREQUENCY-SHIFTED FEEDBACK; CO2 TEA LASER AB We have developed a technique for laser tuning at rates of 100 kHz or more using a pair of acousto-optic modulators. In addition to all-electronic wavelength control, the same modulators also can provide electronically variable Q-switching, cavity length and power stabilization, chirp and linewidth control, and variable output coupling, all at rates far beyond what is possible with conventional mechanically tuned components. Tuning rates of 70 kHz have been demonstrated on a radio-frequency-pumped CO, laser, with random access to over 50 laser lines spanning a 17% range in wavelength and with wavelength discrimination better than 1 part in 1000. A compact tuner and Q-switch has been deployed in a 5-10-kHz pulsed lidar system. The modulators each operate at a fixed Bragg angle, with the acoustic frequency determining the selected wavelength. This arrangement doubles the wavelength resolution without introducing an undesirable frequency shift. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Thompson, DC (reprint author), Los Alamos Natl Lab, MS E548, Los Alamos, NM 87545 USA. EM gbusch@lanl.gov NR 22 TC 16 Z9 16 U1 0 U2 3 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 APR 20 PY 1999 VL 38 IS 12 BP 2545 EP 2553 DI 10.1364/AO.38.002545 PG 9 WC Optics SC Optics GA 186JJ UT WOS:000079725400029 PM 18319825 ER PT J AU Wills, BJ Laor, A Brotherton, MS Wills, D Wilkes, BJ Ferland, GJ Shang, ZH AF Wills, BJ Laor, A Brotherton, MS Wills, D Wilkes, BJ Ferland, GJ Shang, ZH TI The PG X-ray QSO sample: Links between the ultraviolet-X-ray continuum and emission lines SO ASTROPHYSICAL JOURNAL LA English DT Article DE accretion, accretion disks; galaxies : starburst; quasars : emission lines; quasars : general; ultraviolet : galaxies; X-rays : galaxies ID ACTIVE GALACTIC NUCLEI; FE-II EMISSION; C-IV; EVOLUTION; GALAXY AB Two sets of relationships relate QSO UV to soft X-ray continua with the broad-line region. These are (i) the Baldwin relationships, which are inverse relationships between the broad-line equivalent width and the continuum luminosity, and (ii) Boroson & Green's optical "Principal Component 1" relationships, linking steeper soft Xray spectra with narrower H beta emission, stronger HP blue wings, stronger optical Fe II emission, and weaker [O III] lambda 5007 lines. In order to understand these relationships, we extended the spectra into the UV for 22 QSOs with high-quality soft X-ray spectra. These are from the complete sample of QSOs from the Bright Quasar Survey for which Laor et al. demonstrated strong luminosity and X-ray-optical Principal Component 1 relationships. We show that these extend to a whole new set of UV relationships: Principal Component 1 (in the sense of steeper X-ray spectra) is related to narrower C III] lambda 1909 lines, larger Si III] lambda 1892/C III] lambda 1909 ratios (a high-density indicator), stronger low-ionization lines, and weaker C IV lambda 1549 but stronger N V lambda 1240 lines. We speculate that high accretion rates are linked to high columns of dense (similar to 10(11) cm(-3)), nitrogen-enhanced, low-ionization gas from nuclear starbursts. Line width, inverse Fe II-[O III] and inverse Fe II-C IV relationships hint at the geometrical arrangement of this gas. These Principal Component 1 relationships appear to be independent of luminosity and therefore of the Baldwin relationships. C1 Univ Texas, McDonald Obser, Austin, TX 78712 USA. Univ Texas, Dept Astron, Austin, TX 78712 USA. Technion Israel Inst Technol, Dept Phys, IL-32000 Haifa, Israel. Univ Calif Lawrence Livermore Natl Lab, Inst Geophys & Planetary Phys, Livermore, CA 94550 USA. Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA. Univ Kentucky, Dept Phys & Astron, Lexington, KY 40506 USA. RP Wills, BJ (reprint author), Univ Texas, McDonald Obser, RLM 15-308, Austin, TX 78712 USA. OI Wilkes, Belinda/0000-0003-1809-2364; Ferland, Gary/0000-0003-4503-6333 NR 26 TC 61 Z9 61 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 APR 20 PY 1999 VL 515 IS 2 BP L53 EP L56 DI 10.1086/311980 PN 2 PG 4 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA 200EY UT WOS:000080527700003 ER PT J AU Stone, DB Hjelm, RP Mendelson, RA AF Stone, DB Hjelm, RP Mendelson, RA TI Solution structures of dimeric kinesin and ncd motors SO BIOCHEMISTRY LA English DT Article ID SMALL-ANGLE-SCATTERING; X-RAY STRUCTURE; CRYSTAL-STRUCTURE; CRYOELECTRON MICROSCOPY; NEUTRON-SCATTERING; BRAIN KINESIN; NECK REGION; MICROTUBULES; DOMAINS; MOTILITY AB The dimeric structure of the members of the kinesin family of motor proteins determines the individual characteristics of their microtubule-based motility. Crystal structures for ncd and kinesin dimers, which move in opposite directions on microtubules, show possible states of these dimers with ADP bound but give no information about these dimers in solution. Here, low-angle X-ray and neutron scattering were used to investigate their solution structures. Scattering profiles of Drosophila ncd 281-700 (NCD281) and human kinesin 1-420 (hKIN420) were compared with models made from the crystallographically determined structures of NCD281 and rat kinesin 1-379 (rKIN379). From the low-angle region it was found that the radius of gyration (R-g) Of NCD281 is 3.60 +/- 0.075 nm, which is in agreement with the crystallography-based model. Scattering by longer ncd constructs (NCD250 and NCD224)is also well fit by the appropriate crystallography-based models. However, the measured R-g of hKIN420, 4.05 +/- 0.075 nm, is significantly smaller than that of the crystallography-based model. In addition, the overall scattering pattern of NCD281 is well fit by the model, but that of hKIN420 is poorly fit. Model calculations indicate that the orientation of the catalytic cores is different from that observed in the rKIN379 crystal structure. Like the crystal structure, the best-fitting models do not show 2-fold symmetry about the neck axis; however, their overall shape more resembles a mushroom than the 'T"-like orientation of the catalytic cores found in the crystal structure. The center of mass separations of the catalytic cores in the best-fitting models are 0.7-1 nm smaller than in the crystal structure. C1 Univ Calif San Francisco, Cardiovasc Res Inst, San Francisco, CA 94143 USA. Univ Calif San Francisco, Dept Biochem & Biophys, San Francisco, CA 94143 USA. Univ Calif Los Alamos Natl Lab, Los Alamos Neutron Scattering Ctr, Los Alamos, NM 87545 USA. RP Mendelson, RA (reprint author), Univ Calif San Francisco, Cardiovasc Res Inst, San Francisco, CA 94143 USA. RI Lujan Center, LANL/G-4896-2012 FU NCRR NIH HHS [RR-01081]; NIAMS NIH HHS [P01-AR42895] NR 40 TC 12 Z9 12 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0006-2960 J9 BIOCHEMISTRY-US JI Biochemistry PD APR 20 PY 1999 VL 38 IS 16 BP 4938 EP 4947 DI 10.1021/bi982374z PG 10 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 189UL UT WOS:000079924500005 PM 10213595 ER PT J AU Hirasawa, M Schurmann, P Jacquot, JP Manieri, W Jacquot, P Keryer, E Hartman, FC Knaff, DB AF Hirasawa, M Schurmann, P Jacquot, JP Manieri, W Jacquot, P Keryer, E Hartman, FC Knaff, DB TI Oxidation-reduction properties of chloroplast thioredoxins, Ferredoxin : Thioredoxin reductase, and thioredoxin f-regulated enzymes SO BIOCHEMISTRY LA English DT Article ID SPINACH PHOSPHORIBULOKINASE; CHLAMYDOMONAS-REINHARDTII; MALATE-DEHYDROGENASE; CRYSTAL-STRUCTURE; GREEN-ALGA; FRUCTOSE-1,6-BISPHOSPHATASE; SITE; PURIFICATION; RESIDUES; CRYSTALLIZATION AB Oxidation-reduction midpoint potentials were determined, as a function of pH, for the disulfide/dithiol couples of spinach and pea thioredoxins f, for spinach and Chlamydomonas reinhardtii thioredoxins m, for spinach ferredoxin:thioredoxin reductase (FTR), and for two enzymes regulated by thioredoxin f, spinach phosphoribulokinase (PRK)and the fiuctose-1,6-bisphosphatases (FBPase) from pea and spinach. Midpoint oxidation-reduction potential (E-m) values at pH 7.0 of -290 mV for both spinach and pea thioredoxin f, -300 mV for both C. reinhardtii and spinach thioredoxin m, -320 mV for spinach FTR, -290 mV for spinach PRK, -315 mV for pea FBPase, and -330 mV for spinach FBPase were obtained. With the exception of spinach FBPase, titrations showed a single two-electron component at all pH values tested. Spinach FBPase exhibited a more complicated behavior, with a single two-electron component being observed at pH values greater than or equal to 7.0, but with two components being present at pH values <7.0. The slopes of plots of E-m versus pH were close to the -60 mV/pH unit value expected for a process that involves the uptake of two protons per two electrons (i.e., the reduction of a disulfide to two fully protonated thiols) for thioredoxins f and m, for FTR, and for pea FBPase;The slope of the E-m versus pH profile for PRK shows three regions, consistent with the presence of pK(a) values for the two regulatory cysteines in the region between pH 7.5 and 9.0. C1 Texas Tech Univ, Dept Chem & Biochem, Lubbock, TX 79409 USA. Univ Neuchatel, Dept Plant Biochem, CH-2007 Neuchatel, Switzerland. Univ Paris S, Inst Biotechnol Plants, F-91405 Orsay, France. Univ Nancy 1, Associe INRA, Lab Forest Biol, F-54506 Vandoeuvre Nancy, France. Oak Ridge Natl Lab, Div Life Sci, Prot Engn Program, Oak Ridge, TN 37831 USA. RP Knaff, DB (reprint author), Texas Tech Univ, Dept Chem & Biochem, Lubbock, TX 79409 USA. OI Jacquot, Jean-Pierre/0000-0003-4975-8587 NR 43 TC 104 Z9 106 U1 1 U2 9 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0006-2960 J9 BIOCHEMISTRY-US JI Biochemistry PD APR 20 PY 1999 VL 38 IS 16 BP 5200 EP 5205 DI 10.1021/bi982783v PG 6 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA 189UL UT WOS:000079924500037 PM 10213627 ER PT J AU Hochberg, D Perez-Mercader, J Molina-Paris, C Visser, M AF Hochberg, D Perez-Mercader, J Molina-Paris, C Visser, M TI Renormalization group improving the effective action: A review SO INTERNATIONAL JOURNAL OF MODERN PHYSICS A LA English DT Review AB The existence of fluctuations together with interactions leads to scale-dependence, in the couplings of quantum field theories for the case of quantum fluctuations, and in the couplings of stochastic systems when the fluctuations are of a thermal or statistical nature. In both cases the effects of these fluctuations can be accounted for by solutions of the corresponding renormalization group equations. In this review, we show how the renormalization group equations are intimately connected with the effective action: given the effective action we can trivially extract the renormalisation group equations; given the renormalization group equations the effects of these fluctuations can be included in the classical action by using what is known as improved perturbation theory (wherein the bare parameters appearing in tree-level expressions are replaced by their scale-dependent running forms). The improved action can then be used to reconstruct the effective action, up to finite renormalizations, and up to gradient terms. C1 Lab Astrofis Espacial & Fis Fundamental, Madrid 28080, Spain. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Washington Univ, Dept Phys, St Louis, MO 63130 USA. RP Lab Astrofis Espacial & Fis Fundamental, Apartado 50727, Madrid 28080, Spain. EM hochberg@laeff.esa.es; mercader@laeff.esa.es; carmen@t6-serv.lanl.gov; visser@kiwi.wustl.edu OI Visser, Matt/0000-0003-1088-6485 NR 47 TC 5 Z9 5 U1 0 U2 3 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA 5 TOH TUCK LINK, SINGAPORE 596224, SINGAPORE SN 0217-751X EI 1793-656X J9 INT J MOD PHYS A JI Int. J. Mod. Phys. A PD APR 20 PY 1999 VL 14 IS 10 BP 1485 EP 1521 DI 10.1142/S0217751X99000750 PG 37 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA 194LD UT WOS:000080194200001 ER PT J AU McCulloch, A Aucott, ML Benkovitz, CM Graedel, TE Kleiman, G Midgley, PM Li, YF AF McCulloch, A Aucott, ML Benkovitz, CM Graedel, TE Kleiman, G Midgley, PM Li, YF TI Global emissions of hydrogen chloride and chloromethane from coal combustion, incineration and industrial activities: Reactive Chlorine Emissions Inventory SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID ATMOSPHERE; UK AB Much if not all of the chlorine present in fossil fuels is released into the atmosphere as hydrogen chloride (HCl) and chloromethane (CH3Cl, methyl chloride). The chlorine content of oil-based fuels is so low that these sources can be neglected, but coal combustion provides significant releases. On the basis of national statistics for the quantity and quality of coal burned during 1990 in power and heat generation, industrial conversion and residential and commercial heating, coupled with information on the chlorine contents of coals, a global inventory of national HCl emissions from this source has been constructed. This was combined with an estimate of the national emissions of HCl from waste combustion (both large-scale incineration and trash burning) which was based on an estimate of the global quantity released from this source expressed per head of population. Account was taken of reduced emissions where flue gases were processed, for example to remove sulphur dioxide. The HCl emitted in 1990, comprising 4.6 +/- 4.3 Tg Cl from fossil fuel and 2 +/- 1.9 Tg Cl from waste burning, was spatially distributed using available information on point sources such as power generation utilities and population density by default. Also associated with these combustion sources are chloromethane emissions, calculated to be 0.075 +/- 0.07 Tg as Cl (equivalent) from fossil fuels and 0.032 +/- 0.023 Tg Cl (equivalent) from waste combustion. These were distributed spatially exactly as the HCl emissions, and a further 0.007 Tg Cl in chloromethane from industrial process activity was distributed by point sources. C1 ICI Chem & Polymers Ltd, Runcorn WA7 4QF, Cheshire, England. Brookhaven Natl Lab, Upton, NY 11973 USA. Yale Univ, Sch Forestry & Environm Studies, New Haven, CT 06511 USA. MIT, Ctr Global Change Sci, Cambridge, MA 02139 USA. M&D Consulting, D-70771 Leinfelden Musberg, Germany. Environm Canada, Atomospher Environm Serv, Toronto, ON M3H 5T4, Canada. RP McCulloch, A (reprint author), ICI Chem & Polymers Ltd, POB 13,Heath, Runcorn WA7 4QF, Cheshire, England. EM archie_mcculloch@ici.com; maucott@dep.state.nj.us; cmb@bnl.gov; thomas.graedel@yale.edu; gary@jake.mit.edu; PaulineMidgley@compuserve.com; yfli@en.gc.ca NR 32 TC 66 Z9 67 U1 4 U2 24 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 APR 20 PY 1999 VL 104 IS D7 BP 8391 EP 8403 DI 10.1029/1999JD900025 PG 13 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA 187NV UT WOS:000079793600027 ER PT J AU Carmody, M Landree, E Marks, LD Merkle, KL AF Carmody, M Landree, E Marks, LD Merkle, KL TI Determination of the current density distribution in Josephson junctions SO PHYSICA C LA English DT Article DE Josephson junctions; phase retrieval; critical current density ID ALGORITHM; PHASE; IMAGE AB A technique is described for recovering the missing phase information for a set of critical current measurements as a function of an applied magnetic field I-c(B), In many cases the current density j(x) across the boundary for a Josephson junction can be determined. (C) 1999 Published by Elsevier Science B.V. All rights reserved. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Argonne Natl Lab, Sci & Technol Ctr Superconduct, Argonne, IL 60439 USA. Northwestern Univ, Dept Mat Sci & Engn, Evanston, IL 60208 USA. RP Carmody, M (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Marks, Laurence/B-7527-2009 NR 18 TC 8 Z9 8 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 APR 20 PY 1999 VL 315 IS 3-4 BP 145 EP 153 DI 10.1016/S0921-4534(99)00189-6 PG 9 WC Physics, Applied SC Physics GA 196RA UT WOS:000080320300001 ER PT J AU Thevuthasan, S Kim, YJ Yi, SI Chambers, SA Morais, J Denecke, R Fadley, CS Liu, P Kendelewicz, T Brown, GE AF Thevuthasan, S Kim, YJ Yi, SI Chambers, SA Morais, J Denecke, R Fadley, CS Liu, P Kendelewicz, T Brown, GE TI Surface structure of MBE-grown alpha-Fe2O3(0001) by intermediate-energy X-ray photoelectron diffraction SO SURFACE SCIENCE LA English DT Article DE photoelectron diffraction; molecular beam epitaxy; X-ray photoelectron spectroscopy; surface structure; iron oxide; low index single crystal surfaces ID MOLECULAR-BEAM EPITAXY; ELECTRON-DIFFRACTION; WATER-VAPOR; OXIDE; FILMS; OXYGEN; ALPHA-AL2O3(0001); SCATTERING; CHEMISTRY; MGO(001) AB We have used intermediate-energy X-ray photoelectron diffraction to determine the surface structure of epitaxial alpha-Fe2O3(0001) grown on alpha-Al2O3(0001). Comparison of experiment with quantum mechanical scattering theory reveals that the surface is Fe-terminated, and that the first four layer spacings are -41, +18, -8, and 47% of the associated bulk values, respectively. These results agree reasonably well with the predictions of molecular mechanics and spin-density functional theory previously reported in the literature for the Fe-terminated surface. However, we find no evidence for an O-terminated surface predicted to be stable by spin-density functional theory. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Pacific NW Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Stanford Univ, Dept Environm & Geol Sci, Stanford, CA 94305 USA. Stanford Synchrotron Radiat Lab, Stanford, CA 94305 USA. RP Chambers, SA (reprint author), Pacific NW Lab, Environm Mol Sci Lab, POB 999, Richland, WA 99352 USA. EM sa.chambers@pnl.gov RI Morais, Jonder/E-5022-2013 OI Morais, Jonder/0000-0002-4143-1208 NR 33 TC 86 Z9 87 U1 0 U2 17 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 APR 20 PY 1999 VL 425 IS 2-3 BP 276 EP 286 DI 10.1016/S0039-6028(99)00200-9 PG 11 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA 192LM UT WOS:000080080200014 ER PT J AU Yang, Y Leppert, VJ Risbud, SH Twamley, B Power, PP Lee, HWH AF Yang, Y Leppert, VJ Risbud, SH Twamley, B Power, PP Lee, HWH TI Blue luminescence from amorphous GaN nanoparticles synthesized in situ in a polymer SO APPLIED PHYSICS LETTERS LA English DT Article ID NANOCRYSTALLINE GALLIUM NITRIDE; LIGHT-EMITTING-DIODES; LASER-DIODES; THIN-FILMS; ROUTE; GAAS AB Amorphous GaN nanoparticles were synthesized by the in situ thermal decomposition of cyclotrigallazane incorporated into a polystyrene-poly(N,N-dimethyl-4-vinylaniline) copolymer. Transmission electron microscopy, energy dispersive x-ray spectrometry, and x-ray photoelectron spectroscopy show that the composite material consists of amorphous GaN nanoparticles (average diameter similar to 40 nm) well dispersed in the copolymer. The photoluminescence spectra show blue light emission from the amorphous GaN nanoparticles, peaked at similar to 426 nm. (C) 1999 American Institute of Physics. [S0003-6951(99)02616-9]. C1 Univ Calif Davis, Dept Chem Engn & Mat Sci, Davis, CA 95616 USA. Univ Calif Davis, Dept Chem, Davis, CA 95616 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Risbud, SH (reprint author), Univ Calif Davis, Dept Chem Engn & Mat Sci, Davis, CA 95616 USA. NR 20 TC 61 Z9 64 U1 0 U2 12 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD APR 19 PY 1999 VL 74 IS 16 BP 2262 EP 2264 DI 10.1063/1.123819 PG 3 WC Physics, Applied SC Physics GA 186NU UT WOS:000079736500004 ER PT J AU Hader, J Bossert, D Stohs, J Chow, WW Koch, SW Moloney, JV AF Hader, J Bossert, D Stohs, J Chow, WW Koch, SW Moloney, JV TI Clamping of the linewidth enhancement factor in narrow quantum-well semiconductor lasers SO APPLIED PHYSICS LETTERS LA English DT Article ID GAIN SPECTRA; ALPHA AB The linewidth enhancement factor in single quantum-well graded index separate confinement heterostructure semiconductor lasers is investigated theoretically and experimentally. For thin wells, a small linewidth enhancement factor is obtained which clamps with increasing carrier density, in contrast to the monotonous increase observed for thicker wells. Microscopic many-body calculations reproduce the experimental observations attributing the clamping to excitation dependent gain shifts and the influence of the population of off-resonant states on the refractive index. (C) 1999 American Institute of Physics. [S0003-6951(99)04016-4]. C1 Univ Arizona, Arizona Ctr Math Sci, Tucson, AZ 85721 USA. USAF, Phillips Lab, Kirtland AFB, NM 87117 USA. Univ New Mexico, Ctr High Technol Mat, Albuquerque, NM 87106 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. Univ Marburg, Dept Phys, D-35032 Marburg, Germany. Univ Marburg, Ctr Mat Sci, D-35032 Marburg, Germany. RP Hader, J (reprint author), Univ Arizona, Arizona Ctr Math Sci, Tucson, AZ 85721 USA. NR 11 TC 39 Z9 39 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD APR 19 PY 1999 VL 74 IS 16 BP 2277 EP 2279 DI 10.1063/1.123823 PG 3 WC Physics, Applied SC Physics GA 186NU UT WOS:000079736500009 ER PT J AU Pedraza, AJ Fowlkes, JD Lowndes, DH AF Pedraza, AJ Fowlkes, JD Lowndes, DH TI Silicon microcolumn arrays grown by nanosecond pulsed-excimer laser irradiation SO APPLIED PHYSICS LETTERS LA English DT Article AB Arrays of high aspect ratio silicon microcolumns that protrude well above the initial surface have been formed by cumulative nanosecond pulsed-excimer laser irradiation of silicon. Microcolumn growth is strongly affected by the gas environment, being enhanced in air or other oxygen-containing ambient. It is proposed that microcolumn growth occurs through a combination of pulsed-laser melting of the tips of the columns and deposition of silicon from the intense flux of silicon-rich vapor produced by ablation of the surface regions between columns. The molten tips of the columns are strongly preferred sites for deposition, resulting in a very high axial growth rate. The growth process is conceptually similar to the vapor-liquid-solid method used to grow silicon whiskers. However, in the present case the pulsed-laser radiation fulfills two roles almost simultaneously, viz., providing the flux of silicon-containing molecules and melting the tips of the columns. (C) 1999 American Institute of Physics. [S0003-6951(99)04917-7]. C1 Univ Tennessee, Dept Mat Sci & Engn, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Pedraza, AJ (reprint author), Univ Tennessee, Dept Mat Sci & Engn, Knoxville, TN 37996 USA. NR 15 TC 181 Z9 186 U1 2 U2 18 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD APR 19 PY 1999 VL 74 IS 16 BP 2322 EP 2324 DI 10.1063/1.123838 PG 3 WC Physics, Applied SC Physics GA 186NU UT WOS:000079736500024 ER PT J AU Goff, JP Sarthour, RS McMorrow, DF Yakhou, F Stunault, A Vigliante, A Ward, RCC Wells, MR AF Goff, JP Sarthour, RS McMorrow, DF Yakhou, F Stunault, A Vigliante, A Ward, RCC Wells, MR TI X-ray resonant scattering study of spin-density waves in a superlattice SO JOURNAL OF PHYSICS-CONDENSED MATTER LA English DT Letter ID MAGNETIC SCATTERING; EXCHANGE SCATTERING; POLARIZATION; HOLMIUM; PRASEODYMIUM; MULTILAYERS; NEODYMIUM; FIELD AB The magnetic structures of Nd/Pr superlattices have been investigated using x-ray magnetic resonant scattering. Magnetic dipole resonances were observed at the L-II (2p(1/2) --> 5d) edges of both components of the superlattices, proving that a coherent spin-density wave is established in the 5d bands of both elements. Multi-q magnetic structures were induced in the Pr, and the two components of the superlattice were found to adopt identical magnetic modulation vectors. Magnetic superlattice peaks were observed in Q-scans at both edges and from these we were able to determine the magnetization profiles in each component of the superlattice separately. From the width of the magnetic peaks in the wave-vector, Delta Q, we were able to measure the magnetic coherence of the Delta Q, and the results demonstrate that the observed spin-density wave in the Pr is responsible for the coupling between successive Nd blocks. C1 Univ Oxford, Dept Phys, Clarendon Lab, Oxford OX1 3PU, England. Riso Natl Lab, Condensed Matter Phys & Chem Dept, DK-4000 Roskilde, Denmark. European Synchrotron Radiat Facil, F-38043 Grenoble, France. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Goff, JP (reprint author), Univ Oxford, Dept Phys, Clarendon Lab, Parks Rd, Oxford OX1 3PU, England. RI McMorrow, Desmond/C-2655-2008 OI McMorrow, Desmond/0000-0002-4947-7788 NR 19 TC 12 Z9 12 U1 0 U2 3 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 APR 19 PY 1999 VL 11 IS 15 BP L139 EP L146 DI 10.1088/0953-8984/11/15/002 PG 8 WC Physics, Condensed Matter SC Physics GA 189PL UT WOS:000079913700002 ER PT J AU Wignall, GD AF Wignall, GD TI Neutron scattering studies of polymers in supercritical carbon dioxide SO JOURNAL OF PHYSICS-CONDENSED MATTER LA English DT Review ID SMALL-ANGLE NEUTRON; X-RAY-SCATTERING; COMPRESSED FLUID ANTISOLVENT; COPOLYMER MICELLES; WATER; MICROEMULSIONS; POLYSTYRENE; SURFACTANTS; PRESSURE; PRECIPITATION AB Above its critical point, carbon dioxide forms a supercritical fluid (SCF) that promises to be an environmentally responsible replacement for the organic solvents currently used in polymer synthesis and processing. Over the past two decades, small-angle neutron scattering (SANS) has provided a wealth of novel structural information on polymers and, more recently, the technique has been applied to characterize molecules dissolved in CO2 (e.g. fluoropolymers and siloxanes). When the interactions between the chain segments and the surrounding fluid are balanced, the chain trajectory is independent of both segment-segment and solvent-solute interactions. This phenomenon occurs at a 'theta temperature' (T-theta), where chain dimensions correspond to a volumeless polymer coil,`unperturbed' by long range interactions. For T > T-theta, the system exhibits a 'good solvent' domain, where the molecules expand beyond the unperturbed R-g in both organic solvents and in CO2. However, unlike organic solvents, this transition can be made to occur at a critical 'theta pressure' (P-theta) in CO2 and this represents a new concept in the physics of polymer-solvent systems. For T < T-theta, and P < P-theta, the system enters the 'poor solvent' domain, where diverging concentration fluctuations prevent the chains from collapsing and allow them to maintain their unperturbed dimensions. Other polymers such as polystyrene (PS) are insoluble in CO2, though they may be solubilized by means of PS-fluoropolymer stabilizers, which function as surfactants. In the case of such diblock-copolymers, aggregation occurs when the solvent is preferential for one of the blocks and SANS may be used to determine the structure of the aggregates (micelles), which consist of a CO2-phobic core surrounded by a CO2-philic shell. When CO2-insoluble material (e.g. PS) is added to the block-copolymer solutions, virtually all of the material is solubilized in the core. A unique attribute of SCFs is that the solvent quality may be adjusted over a wide range by varying the density (pressure), thus offering significant control over the solubility. This paper will illustrate the use of a tunable solvent to control the quality of the solvent-solute interaction of homopolymers and the self assembly of block-copolymer surfactants. SANS promises to give the same level of insight into polymers and amphiphiles in supercritical media that it has provided in the condensed state, organic solvents and in aqueous systems. C1 Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Wignall, GD (reprint author), Oak Ridge Natl Lab, Div Solid State, POB 2008, Oak Ridge, TN 37831 USA. OI Wignall, George/0000-0002-3876-3244 NR 60 TC 25 Z9 25 U1 3 U2 9 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0953-8984 J9 J PHYS-CONDENS MAT JI J. Phys.-Condes. Matter PD APR 19 PY 1999 VL 11 IS 15 BP R157 EP R177 DI 10.1088/0953-8984/11/15/006 PG 21 WC Physics, Condensed Matter SC Physics GA 189PL UT WOS:000079913700006 ER PT J AU Brace, D Morariu, B Zumino, B AF Brace, D Morariu, B Zumino, B TI Dualities of the matrix model from T-duality of the Type II string SO NUCLEAR PHYSICS B LA English DT Article DE matrix model; non-commutative Yang-Mills; T-duality ID C-STAR-ALGEBRAS; PROJECTIVE-MODULES; BRANES AB We investigate in the Matrix theory framework, the subgroup of dualities of the DLCQ of M-theory compactified on three-tori, which corresponds to T-duality in the auxiliary Type II string theory. We show how these dualities are realized in the supersymmetric Yang-Mills gauge theories on dual non-commutative three-tori. (C) 1999 Elsevier Science B.V. C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Theoret Phys Grp, Berkeley, CA 94720 USA. RP Brace, D (reprint author), Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. EM brace@thwk2.lbl.gov; morariu@thsrv.lbl.gov; zumino@thsrv.lbl.gov NR 43 TC 54 Z9 54 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 APR 19 PY 1999 VL 545 IS 1-3 BP 192 EP 216 DI 10.1016/S0550-3213(99)00009-7 PG 25 WC Physics, Particles & Fields SC Physics GA 196TB UT WOS:000080322700007 ER PT J AU Abe, F Akimoto, H Akopian, A Albrow, MG Amadon, A Amendolia, SR Amidei, D Antos, J Aota, S Apollinari, G Arisawa, T Asakawa, T Ashmanskas, W Atac, M Azzi-Bacchetta, P Bacchetta, N Bagdasarov, S Bailey, MW de Barbaro, P Barbaro-Galtieri, A Barnes, VE Barnett, BA Barone, M Bauer, G Baumann, T Bedeschi, F Behrends, S Belforte, S Bellettini, G Bellinger, J Benjamin, D Bensinger, J Beretvas, A Berge, JP Berryhill, J Bertolucci, S Bettelli, S Bevensee, B Bhatti, A Biery, K Bigongiari, C Binkley, M Bisello, D Blair, RE Blocker, C Bloom, K Blusk, S Bodek, A Bokhari, W Bolla, G Bonushkin, Y Bortoletto, D Boudreau, J Breccia, L Bromberg, C Bruner, N Brunetti, R Buckley-Geer, E Budd, HS Burkett, K Busetto, G Byon-Wagner, A Byrum, KL Campbell, M Caner, A Carithers, W Carlsmith, D Cassada, J Castro, A Cauz, D Cerri, A Chang, PS Chang, PT Chao, HY Chapman, J Cheng, MT Chertok, M Chiarelli, G Chiou, CN Chlebana, F Christofek, L Cropp, R Chu, ML Cihangir, S Clark, AG Cobal, M Cocca, E Contreras, M Conway, J Cooper, J Cordelli, M Costanzo, D Couyoumtzelis, C Cronin-Hennessy, D Culbertson, R Dagenhart, D Daniels, T DeJongh, F Dell'Agnello, S Dell'Orso, M Demina, R Demortier, L Deninno, M Derwent, PF Devlin, T Dittmann, JR Donati, S Done, J Dorigo, T Eddy, N Einsweiler, K Elias, JE Ely, R Engels, E Erdmann, W Errede, D Errede, S Fan, Q Feild, RG Feng, Z Ferretti, C Fiori, I Flaugher, B Foster, GW Franklin, M Freeman, J Friedman, J Frisch, H Fukui, Y Gadomski, S Galeotti, S Gallinaro, M Ganel, O Garcia-Sciveres, M Garfinkel, AF Gay, C Geer, S Gerdes, DW Giannetti, P Giokaris, N Giromini, P Giusti, G Gold, M Gordon, A Goshaw, AT Gotra, Y Goulianos, K Grassmann, H Green, C Groer, L Grosso-Pilcher, C Guillian, G da Costa, JG Guo, RS Haber, C Hafen, E Hahn, SR Hamilton, R Handa, T Handler, R Hao, W Happacher, F Hara, K Hardman, AD Harris, RM Hartmann, F Hauser, J Hayashi, E Heinrich, J Heiss, A Hinrichsen, B Hoffman, KD Holck, C Hollebeek, R Holloway, L Huang, Z Huffman, BT Hughes, R Huston, J Huth, J Ikeda, H Incagli, M Incandela, J Introzzi, G Iwai, J Iwata, Y James, E Jensen, E Joshi, U Kajfasz, E Kambara, H Kamon, T Kaneko, T Karr, K Kasha, H Kato, Y Keaffaber, TA Kelley, K Kennedy, RD Kephart, R Kestenbaum, D Khazins, D Kikuchi, T Kim, BJ Kim, HS Kim, SH Kim, YK Kirsch, L Klimenko, S Knoblauch, D Koehn, P Kongeter, A Kondo, K Konigsberg, J Kordas, K Korytov, A Kovacs, E Kowald, W Kroll, J Kruse, M Kuhlmann, SE Kuns, E Kurino, K Kuwabara, T Laasanen, AT Lami, S Lammel, S Lamoureux, JI Lancaster, M Lanzoni, M Latino, G LeCompte, T Leone, S Lewis, JD Lindgren, M Liss, TM Liu, JB Liu, YC Lockyer, N Long, O Loreti, M Lucchesi, D Lukens, P Lusin, S Lys, J Maeshima, K Maksimovic, P Mangano, M Mariotti, M Marriner, JP Martignon, G Martin, A Matthews, JAJ Mazzanti, P McFarland, K McIntyre, P Melese, P Menguzzato, M Menzione, A Meschi, E Metzler, S Miao, C Miao, T Michail, G Miller, R Minato, H Miscetti, S Mishina, M Miyashita, S Moggi, N Moore, E Morita, Y Mukherjee, A Muller, T Munar, A Murat, P Murgia, S Musy, M Nakada, H Nakaya, T Nakano, I Nelson, C Neuberger, D Newman-Holmes, C Ngan, CYP Nodulman, L Nomerotski, A Oh, SH Ohmoto, T Ohsugi, T Oishi, R Okabe, M Okusawa, T Olsen, J Pagliarone, C Paoletti, R Papadimitriou, V Pappas, SP Parashar, N Parri, A Patrick, J Pauletta, G Paulini, M Perazzo, A Pescara, L Peters, MD Phillips, TJ Piacentino, G Pillai, M Pitts, KT Plunkett, R Pompos, A Pondrom, L Proudfoot, J Ptohos, F Punzi, G Ragan, K Reher, D Reischl, M Ribon, A Rimondi, F Ristori, L Robertson, WJ Robinson, A Rodrigo, T Rolli, S Rosenson, L Roser, R Saab, T Sakumoto, WK Saltzberg, D Sansoni, A Santi, L Sato, H Schlabach, P Schmidt, EE Schmidt, MP Scott, A Scribano, A Segler, S Seidel, S Seiya, Y Semeria, F Shah, T Shapiro, MD Shaw, NM Shepard, PF Shibayama, T Shimojima, M Shochet, M Siegrist, J Sill, A Sinervo, P Singh, P Sliwa, K Smith, C Snider, FD Spalding, J Speer, T Sphicas, P Spinella, F Spiropulu, M Spiegel, L Stanco, L Steele, J Stefanini, A Strohmer, R Strologas, J Strumia, F Stuart, D Sumorok, K Suzuki, J Suzuki, T Takahashi, T Takano, T Takashima, R Takikawa, K Tanaka, M Tannenbaum, B Tartarelli, F Taylor, W Tecchio, M Teng, PK Teramoto, Y Terashi, K Tether, S Theriot, D Thomas, TL Tlurman-Keup, R Timko, M Tipton, P Titov, A Tkaczyk, S Toback, D Tollefson, K Tollestrup, A Toyoda, H Trischuk, W de Troconiz, JF Truitt, S Tseng, J Turini, N Uchida, T Ukegawa, F Valls, J van den Brink, SC Vejcik, S Velev, G Volobouev, I Vidal, R Vilar, R Vucinic, D Wagner, RG Wagner, RL Wahl, J Wallace, NB Walsh, AM Wang, C Wang, CH Wang, MJ Warburton, A Watanabe, T Watts, T Webb, R Wei, C Wenzel, H Wester, WC Wicklund, AB Wicklund, E Wilkinson, R Williams, HH Wilson, P Winer, BL Winn, D Wolinski, D Wolinski, J Worm, S Wu, X Wyss, J Yagil, A Yao, W Yasuoka, K Yeh, GP Yeh, P Yoh, J Yosef, C Yoshida, T Yu, I Zanetti, A Zetti, F Zucchelli, S AF Abe, F Akimoto, H Akopian, A Albrow, MG Amadon, A Amendolia, SR Amidei, D Antos, J Aota, S Apollinari, G Arisawa, T Asakawa, T Ashmanskas, W Atac, M Azzi-Bacchetta, P Bacchetta, N Bagdasarov, S Bailey, MW de Barbaro, P Barbaro-Galtieri, A Barnes, VE Barnett, BA Barone, M Bauer, G Baumann, T Bedeschi, F Behrends, S Belforte, S Bellettini, G Bellinger, J Benjamin, D Bensinger, J Beretvas, A Berge, JP Berryhill, J Bertolucci, S Bettelli, S Bevensee, B Bhatti, A Biery, K Bigongiari, C Binkley, M Bisello, D Blair, RE Blocker, C Bloom, K Blusk, S Bodek, A Bokhari, W Bolla, G Bonushkin, Y Bortoletto, D Boudreau, J Breccia, L Bromberg, C Bruner, N Brunetti, R Buckley-Geer, E Budd, HS Burkett, K Busetto, G Byon-Wagner, A Byrum, KL Campbell, M Caner, A Carithers, W Carlsmith, D Cassada, J Castro, A Cauz, D Cerri, A Chang, PS Chang, PT Chao, HY Chapman, J Cheng, MT Chertok, M Chiarelli, G Chiou, CN Chlebana, F Christofek, L Cropp, R Chu, ML Cihangir, S Clark, AG Cobal, M Cocca, E Contreras, M Conway, J Cooper, J Cordelli, M Costanzo, D Couyoumtzelis, C Cronin-Hennessy, D Culbertson, R Dagenhart, D Daniels, T DeJongh, F Dell'Agnello, S Dell'Orso, M Demina, R Demortier, L Deninno, M Derwent, PF Devlin, T Dittmann, JR Donati, S Done, J Dorigo, T Eddy, N Einsweiler, K Elias, JE Ely, R Engels, E Erdmann, W Errede, D Errede, S Fan, Q Feild, RG Feng, Z Ferretti, C Fiori, I Flaugher, B Foster, GW Franklin, M Freeman, J Friedman, J Frisch, H Fukui, Y Gadomski, S Galeotti, S Gallinaro, M Ganel, O Garcia-Sciveres, M Garfinkel, AF Gay, C Geer, S Gerdes, DW Giannetti, P Giokaris, N Giromini, P Giusti, G Gold, M Gordon, A Goshaw, AT Gotra, Y Goulianos, K Grassmann, H Green, C Groer, L Grosso-Pilcher, C Guillian, G da Costa, JG Guo, RS Haber, C Hafen, E Hahn, SR Hamilton, R Handa, T Handler, R Hao, W Happacher, F Hara, K Hardman, AD Harris, RM Hartmann, F Hauser, J Hayashi, E Heinrich, J Heiss, A Hinrichsen, B Hoffman, KD Holck, C Hollebeek, R Holloway, L Huang, Z Huffman, BT Hughes, R Huston, J Huth, J Ikeda, H Incagli, M Incandela, J Introzzi, G Iwai, J Iwata, Y James, E Jensen, E Joshi, U Kajfasz, E Kambara, H Kamon, T Kaneko, T Karr, K Kasha, H Kato, Y Keaffaber, TA Kelley, K Kennedy, RD Kephart, R Kestenbaum, D Khazins, D Kikuchi, T Kim, BJ Kim, HS Kim, SH Kim, YK Kirsch, L Klimenko, S Knoblauch, D Koehn, P Kongeter, A Kondo, K Konigsberg, J Kordas, K Korytov, A Kovacs, E Kowald, W Kroll, J Kruse, M Kuhlmann, SE Kuns, E Kurino, K Kuwabara, T Laasanen, AT Lami, S Lammel, S Lamoureux, JI Lancaster, M Lanzoni, M Latino, G LeCompte, T Leone, S Lewis, JD Lindgren, M Liss, TM Liu, JB Liu, YC Lockyer, N Long, O Loreti, M Lucchesi, D Lukens, P Lusin, S Lys, J Maeshima, K Maksimovic, P Mangano, M Mariotti, M Marriner, JP Martignon, G Martin, A Matthews, JAJ Mazzanti, P McFarland, K McIntyre, P Melese, P Menguzzato, M Menzione, A Meschi, E Metzler, S Miao, C Miao, T Michail, G Miller, R Minato, H Miscetti, S Mishina, M Miyashita, S Moggi, N Moore, E Morita, Y Mukherjee, A Muller, T Munar, A Murat, P Murgia, S Musy, M Nakada, H Nakaya, T Nakano, I Nelson, C Neuberger, D Newman-Holmes, C Ngan, CYP Nodulman, L Nomerotski, A Oh, SH Ohmoto, T Ohsugi, T Oishi, R Okabe, M Okusawa, T Olsen, J Pagliarone, C Paoletti, R Papadimitriou, V Pappas, SP Parashar, N Parri, A Patrick, J Pauletta, G Paulini, M Perazzo, A Pescara, L Peters, MD Phillips, TJ Piacentino, G Pillai, M Pitts, KT Plunkett, R Pompos, A Pondrom, L Proudfoot, J Ptohos, F Punzi, G Ragan, K Reher, D Reischl, M Ribon, A Rimondi, F Ristori, L Robertson, WJ Robinson, A Rodrigo, T Rolli, S Rosenson, L Roser, R Saab, T Sakumoto, WK Saltzberg, D Sansoni, A Santi, L Sato, H Schlabach, P Schmidt, EE Schmidt, MP Scott, A Scribano, A Segler, S Seidel, S Seiya, Y Semeria, F Shah, T Shapiro, MD Shaw, NM Shepard, PF Shibayama, T Shimojima, M Shochet, M Siegrist, J Sill, A Sinervo, P Singh, P Sliwa, K Smith, C Snider, FD Spalding, J Speer, T Sphicas, P Spinella, F Spiropulu, M Spiegel, L Stanco, L Steele, J Stefanini, A Strohmer, R Strologas, J Strumia, F Stuart, D Sumorok, K Suzuki, J Suzuki, T Takahashi, T Takano, T Takashima, R Takikawa, K Tanaka, M Tannenbaum, B Tartarelli, F Taylor, W Tecchio, M Teng, PK Teramoto, Y Terashi, K Tether, S Theriot, D Thomas, TL Tlurman-Keup, R Timko, M Tipton, P Titov, A Tkaczyk, S Toback, D Tollefson, K Tollestrup, A Toyoda, H Trischuk, W de Troconiz, JF Truitt, S Tseng, J Turini, N Uchida, T Ukegawa, F Valls, J van den Brink, SC Vejcik, S Velev, G Volobouev, I Vidal, R Vilar, R Vucinic, D Wagner, RG Wagner, RL Wahl, J Wallace, NB Walsh, AM Wang, C Wang, CH Wang, MJ Warburton, A Watanabe, T Watts, T Webb, R Wei, C Wenzel, H Wester, WC Wicklund, AB Wicklund, E Wilkinson, R Williams, HH Wilson, P Winer, BL Winn, D Wolinski, D Wolinski, J Worm, S Wu, X Wyss, J Yagil, A Yao, W Yasuoka, K Yeh, GP Yeh, P Yoh, J Yosef, C Yoshida, T Yu, I Zanetti, A Zetti, F Zucchelli, S TI Search for third-generation leptoquarks from technicolor models in p(p)over-bar collisions at root s = 1.8 TeV SO PHYSICAL REVIEW LETTERS LA English DT Article ID EXTENDED TECHNICOLOR; B->S-GAMMA; BREAKING; PHYSICS; VERTEX AB We report the results of a search for technicolor using 110 pb(-1) of pp collisions recorded by the Collider Detector at Fermilab (CDF). In technicolor models containing a technifamily, color-octet technirhos enhance the pair production of color-triplet technipions, which behave as third-generation leptoquarks. From our previously reported search for third-generation leptoquarks, we present constraints on the production of color-triplet technipions and color-octet technirhos as a function of their masses. [S0031-9007(99)08964-4]. C1 Argonne Natl Lab, Argonne, IL 60439 USA. Univ Bologna, Ist Nazl Fis Nucl, I-40127 Bologna, Italy. Brandeis Univ, Waltham, MA 02254 USA. Univ Calif Los Angeles, Los Angeles, CA 90024 USA. Univ Chicago, Chicago, IL 60637 USA. Duke Univ, Durham, NC 27708 USA. Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Florida, Gainesville, FL 32611 USA. Ist Nazl Fis Nucl, Lab Nazl Frascati, I-00044 Frascati, Italy. Univ Geneva, CH-1211 Geneva 4, Switzerland. Harvard Univ, Cambridge, MA 02138 USA. Hiroshima Univ, Higashihiroshima 724, Japan. Univ Illinois, Urbana, IL 61801 USA. McGill Univ, Inst Particle Phys, Montreal, PQ H3A 2T8, Canada. Univ Toronto, Toronto, ON M5S 1A7, Canada. Johns Hopkins Univ, Baltimore, MD 21218 USA. Univ Karlsruhe, Inst Expt Kernphys, D-76128 Karlsruhe, Germany. KEK, Natl Lab High Energy Phys, Ibaraki, Osaka 305, Japan. Ernest Orlando Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. MIT, Cambridge, MA 02139 USA. Univ Michigan, Ann Arbor, MI 48109 USA. Michigan State Univ, E Lansing, MI 48824 USA. Univ New Mexico, Albuquerque, NM 87131 USA. Ohio State Univ, Columbus, OH 43210 USA. Osaka City Univ, Osaka 588, Japan. Univ Padua, Ist Nazl Fis Nucl, Sez Padova, I-35131 Padua, Italy. Univ Penn, Philadelphia, PA 19104 USA. Univ Pisa, Ist Nazl Fis Nucl, I-56100 Pisa, Italy. Scuola Normale Super Pisa, I-56100 Pisa, Italy. Univ Pittsburgh, Pittsburgh, PA 15260 USA. Purdue Univ, W Lafayette, IN 47907 USA. Univ Rochester, Rochester, NY 14627 USA. Rockefeller Univ, New York, NY 10021 USA. Rutgers State Univ, Piscataway, NJ 08855 USA. Acad Sinica, Taipei 11530, Taiwan. Texas A&M Univ, College Stn, TX 77843 USA. Texas Tech Univ, Lubbock, TX 79409 USA. Univ Trieste, Ist Nazl Fis Nucl, Udine, Italy. Univ Tsukuba, Ibaraki, Osaka 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 Abe, F (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Lancaster, Mark/C-1693-2008; Vucinic, Dejan/C-2406-2008; Peters, Michael/B-4973-2009; Nomerotski, Andrei/A-5169-2010; Azzi, Patrizia/H-5404-2012; Punzi, Giovanni/J-4947-2012; Chiarelli, Giorgio/E-8953-2012; Warburton, Andreas/N-8028-2013; Paulini, Manfred/N-7794-2014; Introzzi, Gianluca/K-2497-2015 OI Azzi, Patrizia/0000-0002-3129-828X; Punzi, Giovanni/0000-0002-8346-9052; Chiarelli, Giorgio/0000-0001-9851-4816; Warburton, Andreas/0000-0002-2298-7315; Paulini, Manfred/0000-0002-6714-5787; Introzzi, Gianluca/0000-0002-1314-2580 NR 23 TC 20 Z9 20 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 APR 19 PY 1999 VL 82 IS 16 BP 3206 EP 3211 DI 10.1103/PhysRevLett.82.3206 PG 6 WC Physics, Multidisciplinary SC Physics GA 186PK UT WOS:000079738000004 ER PT J AU Clark, RM Asztalos, SJ Busse, B Chiara, CJ Cromaz, M Deleplanque, MA Diamond, RM Fallon, P Fossan, DB Jenkins, DG Juutinen, S Kelsall, N Krucken, R Lane, GJ Lee, IY Macchiavelli, AO MacLeod, RW Schmid, G Sears, JM Smith, JF Stephens, FS Vetter, K Wadsworth, R Frauendorf, S AF Clark, RM Asztalos, SJ Busse, B Chiara, CJ Cromaz, M Deleplanque, MA Diamond, RM Fallon, P Fossan, DB Jenkins, DG Juutinen, S Kelsall, N Krucken, R Lane, GJ Lee, IY Macchiavelli, AO MacLeod, RW Schmid, G Sears, JM Smith, JF Stephens, FS Vetter, K Wadsworth, R Frauendorf, S TI Shears mechanism in the A similar to 110 region SO PHYSICAL REVIEW LETTERS LA English DT Article ID MAGNETIC ROTATION; COLLECTIVE BANDS; LIFETIMES; ISOTOPES; PB-200; PB-199; NUCLEI; STATES; SN-106; CD-108 AB Lifetimes of states in a rotational-like M1 band in Cd-110 have been determined through a Doppler-shift attenuation method measurement performed with the Gammasphere array. The deduced B(M1) values, which agree well with the predictions of the tilted axis cranking model, clearly confirm that it has the character of a shears band. Using a semiclassical scheme of the coupling of two long j vectors we deduce information on the strength and form of the effective interaction between the constituent nucleons. These results an the first definitive evidence of the shears mechanism and "magnetic rotation" in this mass region. [S0031-9007(99)08994-2]. C1 Lawrence Berkeley Lab, Berkeley, CA 94720 USA. SUNY Stony Brook, Dept Phys, Stony Brook, NY 11794 USA. Univ York, Dept Phys, York YO1 5DD, N Yorkshire, England. Univ Jyvaskyla, Dept Phys, Jyvaskyla, Finland. Forschungszentrum Rossendorf EV, Inst Kern & Hadronenphys, D-01314 Dresden, Germany. RP Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RI Lane, Gregory/A-7570-2011; Kruecken, Reiner/A-1640-2013 OI Lane, Gregory/0000-0003-2244-182X; Kruecken, Reiner/0000-0002-2755-8042 NR 32 TC 60 Z9 61 U1 0 U2 1 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 APR 19 PY 1999 VL 82 IS 16 BP 3220 EP 3223 DI 10.1103/PhysRevLett.82.3220 PG 4 WC Physics, Multidisciplinary SC Physics GA 186PK UT WOS:000079738000007 ER PT J AU Stohlker, T Ludziejewski, T Bosch, F Dunford, RW Kozhuharov, C Mokler, PH Beyer, HF Brinzanescu, O Franzke, B Eichler, J Griegal, A Hagmann, S Ichihara, A Kramer, A Lekki, J Liesen, D Nolden, F Reich, H Rymuza, P Stachura, Z Steck, M Swiat, P Warczak, A AF Stohlker, T Ludziejewski, T Bosch, F Dunford, RW Kozhuharov, C Mokler, PH Beyer, HF Brinzanescu, O Franzke, B Eichler, J Griegal, A Hagmann, S Ichihara, A Kramer, A Lekki, J Liesen, D Nolden, F Reich, H Rymuza, P Stachura, Z Steck, M Swiat, P Warczak, A TI Angular distribution studies for the time-reversed photoionization process in hydrogenlike uranium: The identification of spin-flip transitions SO PHYSICAL REVIEW LETTERS LA English DT Article ID RADIATIVE ELECTRON-CAPTURE; RELATIVISTIC ATOMIC-COLLISIONS; CROSS-SECTIONS; IONS; RETARDATION; PHYSICS AB The K-shell photoelectric effect for a hydrogenlike U91+ ion is studied by its time-reversed process occurring in relativistic collisions between ban uranium ions and low-Z target atoms. In the time-reversed situation, an electron is captured into the Is ground state with the simultaneous emission of a photon. We present an angular differential study of these transitions for laboratory observation angles between nearly 0 degrees and 150 degrees. Our observation of photon emission close to 0 degrees allowed us to identify spin-flip contributions to the photoionization process and to determine their relative strength. [S0031-9007(99)08948-6]. C1 Goethe Univ Frankfurt, Inst Kernphys, D-60486 Frankfurt, Germany. Gesell Schwerionenforsch mbH, D-64220 Darmstadt, Germany. Inst Nucl Studies, PL-05400 Otwock, Poland. Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. Natl Inst Laser Plasma & Radiat Phys, Bucharest 76900, Romania. Hahn Meitner Inst Berlin GmbH, Bereich Theoret Phys, D-14109 Berlin, Germany. Free Univ Berlin, Fachbereich Phys, D-14195 Berlin, Germany. Coll New Jersey, Dept Phys, Trenton, NJ 08650 USA. Kansas State Univ, Manhattan, KS 66506 USA. Japan Atom Energy Res Inst, Tokai, Ibaraki 31911, Japan. Inst Nucl Phys, PL-31342 Krakow, Poland. Jagiellonian Univ, Inst Phys, PL-30059 Krakow, Poland. RP Goethe Univ Frankfurt, Inst Kernphys, D-60486 Frankfurt, Germany. RI Lekki, Janusz/B-5720-2013 NR 19 TC 45 Z9 46 U1 0 U2 1 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 APR 19 PY 1999 VL 82 IS 16 BP 3232 EP 3235 DI 10.1103/PhysRevLett.82.3232 PG 4 WC Physics, Multidisciplinary SC Physics GA 186PK UT WOS:000079738000010 ER PT J AU Guyer, RA TenCate, J Johnson, P AF Guyer, RA TenCate, J Johnson, P TI Hysteresis and the dynamic elasticity of consolidated granular materials SO PHYSICAL REVIEW LETTERS LA English DT Article ID WAVE PROPAGATION AB Quasistatic elasticity measurements on rocks show them to be strikingly nonlinear and to have elastic hysteresis with end point memory. When the model fur this quasistatic elasticity is extended to the description of nonlinear dynamic elasticity the elastic elements responsible for the hysteresis dominate the behavior. Consequently, in a resonant bar, driven to nonlinearity, the frequency shift and the attenuation are predicted to be nonanalytic functions of the strain field. A resonant bar experiment yielding results in substantial qualitative and quantitative accord with these predictions is reported. [S0031-9007(99)08968-1]. C1 Univ Massachusetts, Dept Phys & Astron, Amherst, MA 01003 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Guyer, RA (reprint author), Univ Massachusetts, Dept Phys & Astron, Amherst, MA 01003 USA. NR 15 TC 80 Z9 81 U1 1 U2 7 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD APR 19 PY 1999 VL 82 IS 16 BP 3280 EP 3283 DI 10.1103/PhysRevLett.82.3280 PG 4 WC Physics, Multidisciplinary SC Physics GA 186PK UT WOS:000079738000022 ER PT J AU Rueff, JP Kao, CC Struzhkin, VV Badro, J Shu, J Hemley, RJ Hao, HK AF Rueff, JP Kao, CC Struzhkin, VV Badro, J Shu, J Hemley, RJ Hao, HK TI Pressure-induced high-spin to low-spin transition in FeS evidenced by x-ray emission spectroscopy SO PHYSICAL REVIEW LETTERS LA English DT Article ID ABSORPTION-SPECTROSCOPY; ELECTRONIC-STRUCTURE; HIGH-TEMPERATURE; PHOTOEMISSION; SPECTRA; CORE; IRON; FLUORESCENCE AB We report the observation of the pressure-induced high-spin to low-spin transition in FeS using new high-pressure synchrotron x-ray emission spectroscopy techniques. The transition is evidenced by the disappearance of the low-energy satellite in the Fe KP emission spectrum of FeS. Moreover, the phase transition is reversible and closely related to the structural phase transition from a manganese phosphidelike phase to a monoclinic phase. The study opens new opportunities for investigating the electronic properties of materials under pressure. [S0031-9007(99)08946-2]. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. Carnegie Inst Washington, Geophys Lab, Washington, DC 20015 USA. Carnegie Inst Washington, Ctr High Pressure Res, Washington, DC 20015 USA. RP Rueff, JP (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. RI Struzhkin, Viktor/J-9847-2013; Rueff, Jean-Pascal/D-8938-2016; Badro, James/A-6003-2011 OI Struzhkin, Viktor/0000-0002-3468-0548; Rueff, Jean-Pascal/0000-0003-3594-918X; NR 26 TC 124 Z9 125 U1 0 U2 21 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD APR 19 PY 1999 VL 82 IS 16 BP 3284 EP 3287 DI 10.1103/PhysRevLett.82.3284 PG 4 WC Physics, Multidisciplinary SC Physics GA 186PK UT WOS:000079738000023 ER PT J AU Swanson, BI Brozik, JA Love, SP Strouse, GF Shreve, AP Bishop, AR Wang, WZ Salkola, MI AF Swanson, BI Brozik, JA Love, SP Strouse, GF Shreve, AP Bishop, AR Wang, WZ Salkola, MI TI Observation of intrinsically localized modes in a discrete low-dimensional material SO PHYSICAL REVIEW LETTERS LA English DT Article ID NONLINEAR LATTICE-RELAXATION; CHARGE-TRANSFER EXCITATION; VALENCE METAL-COMPLEXES; SPECTRA; BREATHERS; SOLITONS; SYSTEMS; STATES; ENERGY; RAMAN AB We report the experimental observation of intrinsic dynamically localized vibrational states in crystals of the highly nonlinear halide-bridged mixed-valence transition metal complex {[Pt(en)(2)] [Pt(en)(2)Cl-2] (ClO4)(4)}, where en = ethylenediamine. These states are identified by the distinctive structure and strong redshifts they impose upon the overtone resonance Raman spectra. Quantitative modeling of the observed redshifts is presented based on a nonadiabatic coupled electron-lattice model that self-consistently predicts strong nonlinearity and highly localized multiquanta bound states. [S0031-9007(99)08915-2]. C1 Univ Calif Los Alamos Natl Lab, Chem Sci & Technol Div, Los Alamos, NM 87545 USA. Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Florida State Univ, NHMFL, Tallahassee, FL 32310 USA. Florida State Univ, Dept Phys, Tallahassee, FL 32310 USA. RP Swanson, BI (reprint author), Univ Calif Los Alamos Natl Lab, Chem Sci & Technol Div, POB 1663, Los Alamos, NM 87545 USA. OI Love, Steven/0000-0003-0588-9622 NR 25 TC 250 Z9 254 U1 1 U2 11 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD APR 19 PY 1999 VL 82 IS 16 BP 3288 EP 3291 DI 10.1103/PhysRevLett.82.3288 PG 4 WC Physics, Multidisciplinary SC Physics GA 186PK UT WOS:000079738000024 ER PT J AU Perkins, JD Mascarenhas, A Zhang, Y Geisz, JF Friedman, DJ Olson, JM Kurtz, SR AF Perkins, JD Mascarenhas, A Zhang, Y Geisz, JF Friedman, DJ Olson, JM Kurtz, SR TI Nitrogen-activated transitions, level repulsion, and band gap reduction in GaAs1-xNx with x < 0.03 SO PHYSICAL REVIEW LETTERS LA English DT Article ID ALLOYS; GAASN; ELECTROREFLECTANCE; LUMINESCENCE; DEPENDENCE; ABSORPTION; ENERGY AB We report electroreflectance spectra for a series of GaAs1-xNx samples with x less than 0.03. For all samples, the fundamental band gap transition (E-0) and the transition from the spin-orbit split-off valence band (E-0 + Delta(0)) are observed. For samples with x greater than or equal to 0.008, an additional transition (E+) is observed. With increasing nitrogen content, the increase in E+ is linear in, and nearly equal to, the band gap reduction indicative of a nitrogen-induced level repulsion. The directly observed E+ transition may arise from either a nitrogen-related resonant level or a disorder-activated indirect transition. [S0031-9007(99)08950-4]. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Perkins, JD (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. NR 18 TC 296 Z9 304 U1 1 U2 20 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD APR 19 PY 1999 VL 82 IS 16 BP 3312 EP 3315 DI 10.1103/PhysRevLett.82.3312 PG 4 WC Physics, Multidisciplinary SC Physics GA 186PK UT WOS:000079738000030 ER PT J AU Sieger, MT Schenter, GK Orlando, TM AF Sieger, MT Schenter, GK Orlando, TM TI Stimulated desorption by surface electron standing waves SO PHYSICAL REVIEW LETTERS LA English DT Article ID ABSORPTION FINE-STRUCTURE; KINETIC-ENERGY; ION DESORPTION; BONDING SITES; AUGER; DIFFRACTION; SCATTERING; CHEMISORPTION; SI(111)7X7; CL AB The total electron-stimulated desorption yield of Cl+ ions from the Cl-terminated Si(lll) surface is shown to exhibit fine-structure oscillations as a function of incident electron beam direction. We demonstrate that this fine structure is consistent with quantum-mechanical scattering and interference of the incident electron. Comparison of experimental data to a qualitative theory reveals the site of the excitation responsible for desorption, and the ground-state atomic bonding geometry of the desorbate. The data are consistent with desorption initiated by an excitation localized on the Si atom bonded to Cl. [S0031-9007(99)08922-X]. C1 Pacific NW Lab, WR Wiley Environm Mol Sci Lab, Richland, WA 99352 USA. RP Sieger, MT (reprint author), Pacific NW Lab, WR Wiley Environm Mol Sci Lab, POB 999,MSIN K8-88, Richland, WA 99352 USA. RI Sieger, Matthew/B-4261-2011; Schenter, Gregory/I-7655-2014 OI Sieger, Matthew/0000-0001-7387-3660; Schenter, Gregory/0000-0001-5444-5484 NR 29 TC 6 Z9 6 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD APR 19 PY 1999 VL 82 IS 16 BP 3348 EP 3351 DI 10.1103/PhysRevLett.82.3348 PG 4 WC Physics, Multidisciplinary SC Physics GA 186PK UT WOS:000079738000039 ER PT J AU Andrews, R Jacques, D Rao, AM Derbyshire, F Qian, D Fan, X Dickey, EC Chen, J AF Andrews, R Jacques, D Rao, AM Derbyshire, F Qian, D Fan, X Dickey, EC Chen, J TI Continuous production of aligned carbon nanotubes: a step closer to commercial realization SO CHEMICAL PHYSICS LETTERS LA English DT Article ID DEPOSITION; BUNDLES; NICKEL AB High-purity aligned multi-walled carbon nanotubes (MWNTs) were synthesized through the catalytic decomposition of a ferrocene-xylene mixture at similar to 675 degrees C in a quartz tube reactor and over quartz substrates, with a conversion of similar to 25% of the total hydrocarbon feedstock. Under the experimental conditions used, scanning electron microscope images reveal that the MWNT array grows perpendicular to the quartz substrates at an average growth rate of similar to 25 mu m/h. A process of this nature which does not require preformed substrates, and which operates at atmospheric pressure and moderate temperatures, could be scaled up for continuous or semi-continuous production of MWNTs. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Univ Kentucky, Ctr Appl Energy Res, Lexington, KY 40506 USA. Univ Kentucky, Dept Phys & Astron, Lexington, KY 40506 USA. Univ Kentucky, Dept Chem & Mat Engn, Lexington, KY 40506 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Univ Kentucky, Dept Chem, Lexington, KY 40506 USA. RP Univ Kentucky, Ctr Appl Energy Res, Lexington, KY 40506 USA. EM rao@pop.uky.edu RI Dickey, Elizabeth/A-3368-2011 OI Dickey, Elizabeth/0000-0003-4005-7872 NR 21 TC 741 Z9 775 U1 6 U2 108 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0009-2614 EI 1873-4448 J9 CHEM PHYS LETT JI Chem. Phys. Lett. PD APR 16 PY 1999 VL 303 IS 5-6 BP 467 EP 474 DI 10.1016/S0009-2614(99)00282-1 PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA 190HC UT WOS:000079955900003 ER PT J AU Belyaeva, OV Balanovsky, OP Ashworth, LK Lebedev, YB Spitsyn, VA Guseva, NA Erdes, S Mikulich, AI Khusnutdinova, EK Limborska, SA AF Belyaeva, OV Balanovsky, OP Ashworth, LK Lebedev, YB Spitsyn, VA Guseva, NA Erdes, S Mikulich, AI Khusnutdinova, EK Limborska, SA TI Fine mapping of a polymorphic CA repeat marker on human chromosome 19 and its use in population studies SO GENE LA English DT Article DE cosmid contigs; high-density filters; linguistic families; PCR typing ID DIVERSITY; MICROSATELLITES; MAP AB A highly polymorphic microsatellite (CA)(n)-marker (CAct685) previously isolated from human chromosome 19 cosmid library was localized near GPI in 19q13.1. For the fine localization of this marker, the hybridization with chromosome 19-specific cosmid libraries assembled in contigs was used. Polymorphism analysis of the marker in 12 populations of Russia and neighboring countries showed 14 alleles containing from 16 to 30 repeat units. Populations belonging to Indo-European, Uralic and Altaic linguistic families demonstrated a great similarity in allele frequency profiles. Differences between these populations were lower for CAct685 than for classical markers. Allele distribution of CAct685 in a Chukchi population belonging to the Chukchi-Kamchatkan linguistic family differs from those in all other populations, that may be typical for Mongoloid population or reflect an ethnic history of Chukchi as a small population. Thus use of the CAct685 marker seems to be effective for analysis of distant peoples. (C) 1999 Elsevier Science B.V. All rights reserved. C1 Russian Acad Sci, Inst Mol Genet, Moscow 123182, Russia. Univ Calif Lawrence Livermore Natl Lab, Ctr Human Genome, Livermore, CA 94550 USA. Shemyakin Ovchinnikov Inst Bioorgan Chem, Moscow 117871, Russia. Ctr Med Genet, Moscow 115478, Russia. Inst Rheumatol, Moscow 115461, Russia. Byelarussian Acad Sci, Inst Ethnog, Minsk 220015, Byelarus. Russian Acad Sci, Ural Branch, Dept Biochem & Cytochem, Ufa 450054, Russia. RP Belyaeva, OV (reprint author), Russian Acad Sci, Inst Mol Genet, 46 Kurchatov Sq, Moscow 123182, Russia. RI Lebedev, Yuri/G-6738-2012; Balanovsky, Oleg/G-1549-2014; Erdes, Shandor/B-5717-2016; Khusnutdinova, Elza/A-4810-2013 OI Lebedev, Yuri/0000-0003-4554-4733; Erdes, Shandor/0000-0003-3195-5187; NR 23 TC 3 Z9 4 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0378-1119 J9 GENE JI Gene PD APR 16 PY 1999 VL 230 IS 2 BP 259 EP 266 DI 10.1016/S0378-1119(99)00056-6 PG 8 WC Genetics & Heredity SC Genetics & Heredity GA 190LA UT WOS:000079963300016 PM 10216265 ER PT J AU Belgrader, P Benett, W Hadley, D Richards, J Stratton, P Mariella, R Milanovich, F AF Belgrader, P Benett, W Hadley, D Richards, J Stratton, P Mariella, R Milanovich, F TI Infectious disease - PCR detection of bacteria in seven minutes SO SCIENCE LA English DT Article ID MICROCHIP PCR; INSTRUMENT C1 Univ Calif Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, Livermore, CA 94551 USA. RP Belgrader, P (reprint author), Univ Calif Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, POB 808, Livermore, CA 94551 USA. NR 12 TC 243 Z9 255 U1 8 U2 27 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 APR 16 PY 1999 VL 284 IS 5413 BP 449 EP 450 DI 10.1126/science.284.5413.449 PG 2 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA 187NE UT WOS:000079792200033 PM 10232992 ER PT J AU Bryan, JC Delmau, LH Sachleben, RA Moyer, BA AF Bryan, JC Delmau, LH Sachleben, RA Moyer, BA TI 1,2-bis[2-(pyridin-2-yloxy)ethoxy]benzene SO ACTA CRYSTALLOGRAPHICA SECTION C-CRYSTAL STRUCTURE COMMUNICATIONS LA English DT Article ID ETHERS AB The structure of the title compound, C20H20N2O4, exhibits several intermolecular arene interactions. For example, pi-stacking is observed between two arene rings, with an interplanar distance of roughly 3.6 Angstrom. C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Bryan, JC (reprint author), Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RI Solominow, Sonia/A-4021-2008; Moyer, Bruce/L-2744-2016 OI Moyer, Bruce/0000-0001-7484-6277 NR 11 TC 0 Z9 0 U1 0 U2 0 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0108-2701 J9 ACTA CRYSTALLOGR C JI Acta Crystallogr. Sect. C-Cryst. Struct. Commun. PD APR 15 PY 1999 VL 55 BP 618 EP 620 DI 10.1107/S0108270198016722 PN 4 PG 3 WC Chemistry, Multidisciplinary; Crystallography SC Chemistry; Crystallography GA 191AK UT WOS:000079998000061 ER PT J AU Xiang, F Lin, YH Wen, J Matson, DW Smith, RD AF Xiang, F Lin, YH Wen, J Matson, DW Smith, RD TI An integrated microfabricated device for dual microdialysis and on-line ESI ion trap mass spectrometry for analysis of complex biological samples SO ANALYTICAL CHEMISTRY LA English DT Article ID CAPILLARY-ELECTROPHORESIS; ELECTROSPRAY-IONIZATION; PCR AMPLIFICATION; MICROCHIP; CHIP; SEPARATION; INJECTION; PEPTIDES; OLIGONUCLEOTIDES; SENSITIVITY AB A microfabricated dual-microdialysis device in a single integrated microfabridated platform was constructed using laser micromachining techniques for the rapid fractionation and cleanup of complex biological samples. On-line dual microdialysis and ESI-MS of biological samples was demonstrated using an ion trap mass spectrometer. The mass spectra obtained demonstrated the efficiency of dual microdialysis for removing both high-molecular-weight and low-molecular-weight species that interfere with effective ESI-MS analysis of target biopolymers. Signal-to-noise ratios were also greatly improved compared to direct sample infusion. In addition to its compactness, negligible dead volume, and robustness, the device can be used at a now rate of only 200 nL/min, an order of magnitude lower than that obtained previously. This reduced sample consumption and improved sensitivity with ESI-MS. The results suggest the potential for integration of such microfabricated devices with other sample manipulations for the rapid ESI-MS analysis of complex biological samples. 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, POB 999, Richland, WA 99352 USA. RI Lin, Yuehe/D-9762-2011; Smith, Richard/J-3664-2012 OI Lin, Yuehe/0000-0003-3791-7587; Smith, Richard/0000-0002-2381-2349 NR 32 TC 108 Z9 111 U1 1 U2 19 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 APR 15 PY 1999 VL 71 IS 8 BP 1485 EP 1490 DI 10.1021/ac981400w PG 6 WC Chemistry, Analytical SC Chemistry GA 186XU UT WOS:000079756900001 PM 10221069 ER PT J AU Woltman, SJ Even, WR Weber, SG AF Woltman, SJ Even, WR Weber, SG TI Chromatographic detection using tris(2,2 '-bipyridyl)ruthenium(III) as a fluorogenic electron-transfer reagent SO ANALYTICAL CHEMISTRY LA English DT Article ID ELECTROGENERATED CHEMILUMINESCENCE DETECTION; ELECTROCHEMICAL DETECTION; FLOWING STREAMS; CAPILLARY ELECTROPHORESIS; POLYPYRIDINE COMPLEXES; FLUORESCENCE DETECTION; LIQUID-CHROMATOGRAPHY; TYROSINE; TRYPTOPHAN; DYNORPHIN AB Tris(2,2'-bipyridyl)ruthenium can be excited to fluorescence by visible light (lambda(abs) 454 nm, lambda(em) 607 nn) when in the M(II) oxidation state, but not in the M(III) state. A novel chromatographic detection method using the non-fluorescent M(III) form of the complex as a postcolumn fluorogenic reagent is demonstrated. The M(III) form is a powerful oxidizing agent (E-o = 1.27 V vs NHE, 1.05 V vs Ag/AgCl). The M(nr) reagent is generated on-line from the M(II) form of the complex by a highly efficient porous carbon electrode and then reacted briefly with chromato-graphic effluent; the M(II) created by electron transfer from oxidation-susceptible analytes is then detected by fluorescence. The fluorescence detector can be calibrated for number of electrons transferred by injection of either M(II) or an oxidative standard such as ferrocyanide. It is hoped that this redox-based detection scheme will provide an alternative to electrochemical detection, Among the advantages are freedom fi om surface fouling and the potential for extremely low detection limits. The scheme was applied to detection of the peptide dynorphin A and several of its fragments. Dynorphin A contains tyrosine at the N-terminus (position 1) and tryptophan in position 15; these amino acid residues are susceptible to oxidation and peptides containing them can be detected on that basis. Flow injection testing of the model compounds Tyr-Gly-Gly-Phe-Leu and Gly-Gly-Trp-Gly indicated that tyrosine transferred similar to 1 electron to the M(III) reagent and that tryptophan transferred similar to 4 electrons, Similar results were obtained from the chromatographic runs. Dynorphin A and six dynorphin A fragments containing the N-terminal tyrosine were detected easily at 100 nM concentration (14 pmol) using laser-induced fluorescence. As expected, one fragment that did not contain tryptophan or tyrosine was not detected. A mass detection limit of 80 fmol was estimated far the tyrosine-containing fragments. 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 34 TC 16 Z9 16 U1 0 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0003-2700 J9 ANAL CHEM JI Anal. Chem. PD APR 15 PY 1999 VL 71 IS 8 BP 1504 EP 1512 DI 10.1021/ac981181e PG 9 WC Chemistry, Analytical SC Chemistry GA 186XU UT WOS:000079756900005 PM 10221071 ER PT J AU Volkov, ND Wang, GJ Fischman, MW Foltin, RW Fowler, JS Abumrad, NN Vitkun, S Logan, J Gatley, SJ Pappas, N Hitzemann, R AF Volkov, ND Wang, GJ Fischman, MW Foltin, RW Fowler, JS Abumrad, NN Vitkun, S Logan, J Gatley, SJ Pappas, N Hitzemann, R TI Occupancy of the dopamine transporter and the cocaine "high" SO BIOLOGICAL PSYCHIATRY LA English DT Meeting Abstract C1 Brookhaven Natl Lab, Upton, NY 11973 USA. SUNY Stony Brook, Stony Brook, NY 11794 USA. Columbia Univ, New York, NY 10032 USA. N Shore Univ Hosp, Manhasset, NY 11030 USA. NR 0 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 0006-3223 J9 BIOL PSYCHIAT JI Biol. Psychiatry PD APR 15 PY 1999 VL 45 IS 8 SU S MA 171 BP 53S EP 54S PG 2 WC Neurosciences; Psychiatry SC Neurosciences & Neurology; Psychiatry GA 189NN UT WOS:000079911600171 ER PT J AU Mason, GF Pan, JW Chu, WJ Newcomer, BR Zhang, Y Hetherington, HP AF Mason, GF Pan, JW Chu, WJ Newcomer, BR Zhang, Y Hetherington, HP TI Glutamate turnover, oxidation in human grey and white matter by H-1/C-13 MRS SO BIOLOGICAL PSYCHIATRY LA English DT Meeting Abstract C1 Yale Univ, Sch Med, Dept Psychiat, New Haven, CT 06520 USA. Brookhaven Natl Lab, Dept Med, Upton, NY 11973 USA. Univ Alabama, Birmingham, AL 35294 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0006-3223 J9 BIOL PSYCHIAT JI Biol. Psychiatry PD APR 15 PY 1999 VL 45 IS 8 SU S MA 192 BP 61S EP 61S PG 1 WC Neurosciences; Psychiatry SC Neurosciences & Neurology; Psychiatry GA 189NN UT WOS:000079911600192 ER PT J AU Volkow, ND Wang, GJ Fowler, JS Gatley, SJ Fischman, M Foltin, R Abumrad, NN Logan, J Hitzemann, R AF Volkow, ND Wang, GJ Fowler, JS Gatley, SJ Fischman, M Foltin, R Abumrad, NN Logan, J Hitzemann, R TI Imaging the translation of preclinical studies with stimulant drugs into the human brain SO BIOLOGICAL PSYCHIATRY LA English DT Meeting Abstract C1 Brookhaven Natl Lab, Upton, NY 11973 USA. SUNY Stony Brook, Dept Psychiat, Stony Brook, NY 11794 USA. Columbia Univ, Dept Psychiat, New York, NY 10032 USA. N Shore Univ Hosp, Dept Surg, Manhasset, NY 11030 USA. NR 0 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 0006-3223 J9 BIOL PSYCHIAT JI Biol. Psychiatry PD APR 15 PY 1999 VL 45 IS 8 SU S MA 329 BP 102S EP 102S PG 1 WC Neurosciences; Psychiatry SC Neurosciences & Neurology; Psychiatry GA 189NN UT WOS:000079911600328 ER PT J AU Tebbs, RS Flannery, ML Meneses, JJ Hartmann, A Tucker, JD Thompson, LH Cleaver, JE Pedersen, RA AF Tebbs, RS Flannery, ML Meneses, JJ Hartmann, A Tucker, JD Thompson, LH Cleaver, JE Pedersen, RA TI Requirement for the Xrcc1 DNA base excision repair gene during early mouse development SO DEVELOPMENTAL BIOLOGY LA English DT Article DE XRCC1; base excision repair; DNA damage; gene targeting; mouse; embryonic lethality ID SISTER-CHROMATID EXCHANGE; IONIZING-RADIATION SENSITIVITY; MOLECULAR NICK-SENSOR; STRAND-BREAK REPAIR; LIGASE-III; POLYMERASE-BETA; POLY(ADP-RIBOSE) POLYMERASE; MICE LACKING; IN-VITRO; EMBRYONIC LETHALITY AB Surveillance and repair of DNA damage are essential for maintaining the integrity of the genetic information that is needed for normal development. Several multienzyme pathways, including the excision repair of damaged or missing bases, carry out DNA repair in mammals. We determined the developmental role of the X-ray cross-complementing (Xrcc)-1 gene, which is central to base excision repair, by generating a targeted mutation in mice. Heterozygous matings produced Xrcc1(-/-) embryos at early developmental stages, but not Xrcc1(-/-) late-stage fetuses or pups. Histology showed that mutant (Xrcc1(-/-)) embryos arrested at embryonic day (E) 6.5 and by E7.5 were morphologically abnormal. The most severe abnormalities observed in mutant embryos were in embryonic tissues, which showed increased cell death in the epiblast and an altered morphology in the visceral embryonic endoderm. Extraembryonic tissues appeared relatively normal at E6.5-7.5. Even without exposure to DNA-damaging agents, mutant embryos showed increased levels of unrepaired DNA strand breaks in the egg cylinder compared with normal embryos. Xrcc1(-/-) cell lines derived from mutant embryos were hypersensitive to mutagen-induced DNA damage. Xrcc1 mutant embryos that were also made homozygous for a null mutation in Trp53 underwent developmental arrest after only slightly further development, thus revealing a Trp53-independent mechanism of embryo lethality. These results show that an intact base excision repair pathway is essential for normal early postimplantation mouse development and implicate an endogenous source of DNA damage in the lethal phenotype of embryos lacking this repair capacity, (C) 1999 Academic Press. C1 Univ Calif San Francisco, Dept Dermatol, San Francisco, CA 94143 USA. Univ Calif San Francisco, Dept Obstet Gynecol & Reprod Sci, Reprod Genet Unit, San Francisco, CA 94143 USA. Novartis Pharma AG, Genet Toxicol, CH-2004 Basel, Switzerland. Univ Calif Lawrence Livermore Natl Lab, Biol & Biotechnol Res Program, Livermore, CA 94550 USA. RP Tebbs, RS (reprint author), Univ Calif San Francisco, Dept Dermatol, San Francisco, CA 94143 USA. FU NICHD NIH HHS [HD26732]; NIEHS NIH HHS [ES07106, ES08750] NR 75 TC 226 Z9 231 U1 1 U2 6 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0012-1606 J9 DEV BIOL JI Dev. Biol. PD APR 15 PY 1999 VL 208 IS 2 BP 513 EP 529 DI 10.1006/dbio.1999.9232 PG 17 WC Developmental Biology SC Developmental Biology GA 189TX UT WOS:000079923200022 PM 10191063 ER EF